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FIELD OF THE INVENTION
[0001] The invention concerns an arrangement for driving a discharge spout of an agricultural harvesting machine, and more specifically, concerns a drive including a motor, that is connected with the discharge spout over a driveline, and is arranged to pivot the spout about an approximately vertical axis, where an overload clutch is inserted into the driveline that interrupts the driveline when a threshold value of the torque transmitted to the discharge spout is exceeded.
BACKGROUND OF THE INVENTION
[0002] In harvesting machines with discharge spouts that can be rotated about a vertical axis, such as combines with ejection ducts and forage harvesters with curved ejection ducts, there is the danger that the discharge spout can be damaged if it is thrown against an obstacle, such as a tree standing at the edge of the field, a power line pole or a transport vehicle operating alongside.
[0003] EP 0 492 195 A proposes that the drive arrangement including a worm gear meshed with a turning circle of a curved discharge duct of a forage harvester will automatically disengage when excessive torques are applied to the discharge duct. Thereby the curved discharge duct can rotate freely and avoid an obstacle. The worm gear is blocked in the disengaged position by a blocking pawl. Therefore an operator must again release the blocking pawl after the trouble has been removed. The operator must therefore climb out of the operator's cab in order to release the blocking pawl at a location that is difficult to access and can continue the operation only after that. The free rotation of the curved discharge duct after the worm gear has been disengaged also has its problems, because after a first impact with an obstacle it can then recoil and collide with another obstacle and be damaged thereby.
[0004] EP 0 672 339 A proposes that a shear pin be inserted into the driveline of the curved discharge duct of a forage harvester which shears upon unusual loading of the curved discharge duct. After the end of the unusual overload the shear pin must be replaced since it is usually located in a relatively inaccessible location this is possible only with a considerable time delay. If no shear pin is available the forage harvester cannot be used for an extended period of time. Furthermore the aforementioned disadvantages of the ability to rotate freely still remains.
[0005] EP 1 092 342 A discloses a forage harvester whose curved discharge duct can be moved by a hydraulic motor. A pressure relief valve and feeder valve are arranged between the supply line and/or the return line of the hydraulic motor and the oil leakage line. The result is that in the case of a collision the hydraulic motor acts as a pump and brakes the curved discharge duct with a specified force. If it is driven for repositioning of the curved discharge duct just at the point of impact, the oil pressure that drives it is bled off by the pressure relief valve. The disadvantage here is that the hydraulic motor provides a relatively high braking effect on the basis of the gear ratio of the intervening gearbox, so that damage to the curved discharge duct remains conceivable. This solution is also relatively expensive and costly due to the necessary hydraulic elements.
[0006] The problem underlying the invention is seen in the need to define an arrangement that is not too costly for the drive of a discharge spout that avoids damage to the discharge spout in the case of an impact of the discharge spout with an obstacle and that is distinguished by operator friendliness.
SUMMARY OF THE INVENTION
[0007] According to the present invention, there is provided an improved drive for repositioning the discharge duct or spout of an agricultural harvester.
[0008] An object of the invention is to provide a drive arrangement for a discharge spout which includes an overload clutch that automatically reestablishes the driving connection between the drive motor and the discharge spout as soon as the excessive torque acting upon the discharge spout is reduced. In normal operation the overload clutch transmits the driving torque from the drive motor to the discharge spout. Thus, the overload clutch separates the driveline, that connects the drive motor with the discharge spout so as to transmit normal torque, in the event the torque to be transmitted exceeds a threshold value, as may be caused by the discharge spout striking an obstacle during the operation, resulting in the discharge spout transmitting a torque to the drive motor, or as may be caused by the drive motor forcing the discharge spout against a fixed obstacle resulting in an applied load exceeding the normal torque. When the discharge spout no longer interacts with the obstacle the overload clutch again engages automatically, so that normal operation is again possible. Appropriate overload clutches are, for example, cam controlled clutches and star ratchets.
[0009] In this way damage to the discharge spout is avoided by simple means and after an impact with an obstacle normal operation is again immediately possible.
[0010] Yet another object of the invention is to provide a drive for a discharge spout that includes a clutch that is operable for providing a braking force that acts to prevent the discharge spout from swinging freely after an impact with an obstacle. An example of an overload clutch which is operable to provide a braking torque after it has interrupted the driveline is a friction clutch.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] [0011]FIG. 1 is a schematic left side elevational view of a harvesting machine, which is an exemplar of a machine with which the present invention is particularly adapted for use.
[0012] [0012]FIG. 2 is a schematic view showing a drive coupled for rotating the discharge spout of the harvesting machine of FIG. 1.
[0013] [0013]FIG. 3 shows a cross section of the overload clutch illustrated in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] Referring now to FIG. 1, there is shown a harvesting machine 10 in the form of a self-propelled forage harvester including a main frame 12 that is carried on front and rear wheels 14 and 16 . The operation of the harvesting machine 10 is controlled from an operator's cab 18 from which a crop recovery arrangement 20 can be viewed. Crop taken up from the ground by means of the crop recovery arrangement 20 , for example, corn, grass or the like is conducted to a chopper drum 22 that chops it into small pieces and delivers it to a conveyor arrangement 24 . The conveyor arrangement 24 conveys the crop in a rigid ejection tower 42 , that extends approximately vertically, that is followed by a discharge spout 26 that can be rotated relative to the ejection tower 42 about an approximately vertical axis and is in the form of a curved ejection duct. The crop leaves the harvesting machine 10 over the discharge spout 26 and is thrown to a container of a transport vehicle operating alongside. Between the chopper drum 22 and the conveyor arrangement 24 a post-chopper reduction arrangement 27 extends, that can be selectively inserted and removed from the flow of the crop, by means of which the crop to be conveyed is conducted tangentially to the conveyor arrangement 24 .
[0015] The position of the discharge spout 26 can be changed by three actuators 30 , 34 and 38 . A first actuator or drive arrangement 30 , described in greater detail below, is used for the rotation of the discharge spout 26 , that is supported in bearings, free to rotate, about a vertical axis on a turning circle 28 . The actuator 30 thereby makes it possible to rotate the discharge spout 26 to the rear into the transport position shown in FIG. 1, or to rotate it to the left or the right alongside the harvesting machine 10 . A second actuator 34 in the form of a hydraulic cylinder is arranged to pivot the discharge spout 26 about a horizontal axis 32 located at its upstream end. Thereby the second actuator 34 defines the height of the downstream end of the discharge spout 26 . A third actuator 38 in the form of a hydraulic cylinder is used to pivot an ejection door 36 at the downstream end 40 of the discharge spout 26 . The ejection door 36 can be adjusted so as to make it possible to control the angle at which the harvested crop leaves the discharge spout 26 . The actuators 34 and 38 are single acting or double acting hydraulic cylinders, where in the case of single acting hydraulic cylinders the weight of the discharge spout 26 itself or the ejection door 36 itself make possible the return movement.
[0016] [0016]FIG. 2 shows the turning circle 28 and the actuator or drive arrangement 30 , which is provided for the rotation of the discharge spout 26 about the vertical axis, in greater detail. In the interior of the turning circle 28 , the underside of the discharge spout 26 is supported relative to the ejection tower 42 in rolling contact bearings, free to rotate (but not shown for the sake of clarity). At the outer circumference of the turning circle 28 , a first, ring-shaped gear 29 is arranged that is locked to transmit torque to the discharge spout 26 . The gear teeth of the first gear 29 mesh with a second gear 46 , that is connected for receiving torque transmitted to it by a first, vertical shaft 58 . The first shaft 58 is connected so as to be driven by an overload clutch 48 which is connected over a second shaft 60 , that is also vertical, to a third gear 50 so as to transmit driving torque to the clutch 48 . The third gear 50 meshes with a worm gear drive 52 , that rotates about a horizontal axis which is coupled to a drive motor 54 in the form of a hydraulic motor. The shafts 58 and 60 as well as the worm drive gear 52 are supported in bearings, not shown, directly or indirectly on the frame 12 of the harvesting machine 10 . The drive motor 54 is also connected directly or indirectly to the frame 12 of the harvesting machine 10 .
[0017] Thereby the drive motor 54 is arranged to pivot the discharge spout 26 about the vertical axis over a driveline consisting of the worm gear drive gear 52 , the third gear 50 , the second shaft 60 , the overload clutch 48 , the first shaft 58 , the second gear 46 and the first gear 29 . The drive motor 54 is controlled by an operator in the operator's cab 18 .
[0018] A sensor 56 is provided that can determine the angle of rotation of the discharge spout 26 by any desired means in order to display to an operator in the operator's cab 18 information about the immediate angle of rotation of the discharge spout 26 or in order to use this information for the control of the control arrangement that is arranged to bring the discharge spout 26 into a desired position by control of the drive motor 54 , which position can be provided as input by the operator or otherwise automatically controlled. The sensor 56 may, for example, be an incremental angle transmitter that operates optically and interacts with corresponding markings on the discharge spout 26 . It can also operate on an inductive basis and interact with permanent magnets attached to the discharge spout 26 .
[0019] The overload clutch 48 is configured in such a way that it disengages when a defined torque transmitted by the second shaft 60 to the first shaft 58 (or the reverse) is exceeded, that is, it interrupts the transmission of torque between the first shaft 58 and the second shaft 60 . In this way the discharge spout 26 —otherwise not supported on the frame 12 —becomes able to rotate about the vertical axis in the case of an overload and can avoid being damaged by coming into contact with obstacles. The result is that the discharge spout 26 is not damaged, if the drive motor 54 forces the discharge spout 26 against an obstacle, for example, the transport vehicle operating alongside the harvesting machine for the chopped crop, or if the discharge spout 26 collides with an obstacle during the operation. Furthermore, in such cases, any damage to the drive motor 54 and the other mechanical elements of the actuator 30 need not be feared.
[0020] The overload clutch 48 , according to the invention, interrupts the driving connection, as soon as the difference of the torques between the first and second shafts 58 and 60 , respectively, exceeds a defined threshold. When the threshold value is no longer exceeded, the driving connection is automatically re-established. For the overload clutch 48 , a device known in itself, such as a star ratchet, a friction clutch or a cam controlled clutch can be employed. Overload clutches of this type are commercially available from the firm GKN Walterscheid, 53797 Lohmar, Del. under the designations K32B, K94B or K64/1. Appropriate overload clutches are also disclosed in the publications DE 31 51 486 C, DE 34 18 558 C, DE 41 37 829 A, DE 195 38 351 C, DE 196 11 622 C, DE 197 15 269 C and DE 197 44 154 C, whose disclosures are incorporated into the present application by reference.
[0021] A possible embodiment of an overload clutch 48 is shown in FIG. 3. The overload clutch 48 includes a cylindrical housing 62 having a bottom 64 and a cover 66 . The bottom 64 is connected with the second shaft 60 and oriented coaxially to it. The cover 66 is screwed onto the housing 62 and contains a central opening through which the first shaft 58 extends. A first friction lining 68 is fastened to the bottom 64 . A second friction lining 70 is located on the first friction lining 68 and is connected with a carrier 74 on its surface opposite the first friction lining 68 . The carrier 74 is connected with a stub shaft 72 , that is arranged coaxially to the first shaft 58 . The stub shaft 72 and the lower end of the first shaft 58 engage each other and can slide relative to each other in the vertical direction, but are coupled to each other so as to transmit torque, since their cross sections are non-circular. The inner cross section of the lower end of the first shaft 58 and the outer cross section of the stub shaft 72 may, for example, be square. The first shaft 58 carries a ring 76 on which a helical spring 78 is supported, which forces the carrier 74 downward and thereby forces the second friction lining 70 against the first friction lining 68 . Obviously it would be conceivable to subdivide the first shaft 58 into two partial parts that can be separated from each other of which only one extends into the housing 62 . Thereby the assembly and the replacement of the overload clutch 48 would be simplified. The second shaft 60 could also be separable from the overload clutch 48 .
[0022] The torque from the second shaft 60 is transmitted over the bottom 64 to the first friction lining 68 . From there it is transmitted to the second friction lining 70 and over the carrier 74 and the stub shaft 72 to the first shaft 58 . If the torque transmitted exceeds a threshold value, that is a function of the material and the dimensions of the friction linings 68 and 70 and the force of the helical spring 78 , the friction linings 68 and 70 begin to rotate relative to each other. The driving connection is interrupted. In the case of an impact of the discharge spout 26 against an obstacle, the spout 26 can therefore avoid being damaged by the impact. If the discharge spout 26 is blocked mechanically by an obstacle, it can then not be damaged when the drive motor 54 is in operation because of the interrupted driving connection. Simultaneously, the friction linings 68 and 70 rubbing against each other generate a braking torque that prevents a free rotation of the discharge spout 26 and possible impact with a second obstacle. As soon as the torque transmitted no longer exceeds the threshold value, the driving connection is reestablished. The operator in the operator's cab 18 or the control arrangement described above can thereby rotate the discharge spout 26 again by operation of the drive motor 54 , as soon as the discharge spout 26 is no longer blocked.
[0023] Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims. | 4y
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FIELD OF THE INVENTION
The present invention relates generally to an electromagnetic energy spot curing system, and more particularly to an integration of inert gas to an UV curing source unit to overcome oxygen inhibition.
BACKGROUND OF THE INVENTION
Ultraviolet (UV) lamps are well-known in the art to cure certain curable compounds such as adhesives and the like. UV spot curing systems are used in various applications including the curing of industrial sealants for potting electronics, bonding plastics in the medical industry and the curing of dental filling materials, disk drive industry amongst other applications. Generally, the presence of air would reduce curing of the adhesive. During photopolymerization, as you radiate UV energy or light, the free radicals that are formed during curing are destroyed by reaction with oxygen from the air. Therefore, it is desired to integrate an inert gas with an UV irradiance onto the adhesive surface during the curing cycle. This integration of the inert gas overcomes oxygen inhibition associated with photopolymerization of acrylate/methacrylate products.
UV curing devices for curing adhesive between two layers of an information carrier, used particularly for disk drive industry, are disclosed in U.S. Pat. Nos. 6,361,846; 6,170,172; 6,148,542 and 6,108,933. The devices described in these patents is a device that cures the adhesive by means of UV radiation in an inert-gas atmosphere. These devices include a curing chamber or enclosure filled with inert gas that isolates the adhesive from the atmospheric oxygen. However, such devices do not have the ability to accurately focus the light to a confined area or location. Also, the reactive material is required to be enclosed in a chamber. Finally, the curing is performed at a low irradiation intensity making the curing process slow and inefficient.
Therefore, a need exists to provide a spot curing system which overcomes the deficiencies of the prior art.
SUMMARY OF THE INVENTION
The present invention provides an electromagnetic energy spot curing method and system which produces an extremely high UV irradiance resulting in a faster and more efficient process. The system is capable of accurately focusing the light to a specific area needed to be cured. Moreover, the material to be cured need not be enclosed in a chamber. Furthermore, the spot curing system of the present invention is portable and can be integrated into a continuous throughput production system.
The system includes a curing unit having a radiation source positioned to irradiate a work piece with radiation energy. A light guide is positioned opposite the curing unit having a light entrance end for receiving the radiation energy and a light exit end for dispersing the radiation energy on the work piece. The system also includes a tube positioned generally parallel to the light guide having a first end for receiving an inert gas and a second end for dispersing the inert gas on the work piece. Moreover, the system includes a fixture where the light exit end of the light guide is integrated with the second end of the inert gas to disperse the gas and the radiation energy simultaneously onto the work piece thereby curing an adhesive surface on the work piece.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of UV spot cure system in accordance with the subject of the invention.
FIG. 2 is a top and front view of the light guide with inert gas attachment of the system.
DETAILED DESCRIPTION OF THE INVENTION
The subject invention relates to an electromagnetic energy spot curing system which utilizes a source of radiation found in the electromagnetic spectrum (e.g., ultraviolet (UV); infrared). To describe the invention and illustrate its functioning, reference is made herein to the use of a UV lamp. It is to be understood that the UV lamp can be interchanged with other sources of electromagnetic energy. In addition, the electromagnetic energy source may provide electromagnetic energy of varying intensities and/or of varying wavelengths (e.g., various types of radiation).
With reference to FIGS. 1 and 2 , an electromagnetic energy spot curing system is generally shown and designated therein with the reference numeral 10 .
The system 10 includes a UV lamp 11 , including a light source 12 and an elliptic reflector 13 . The light source 12 is preferably connected to the elliptic reflector 13 so that the energy emanated from the UV lamp 11 is focused at a precise desired location which is an entrance to a light guide 20 .
The UV lamp 11 may preferably be a conventional straight mercury arc lamp, metal halide mercury lamp, a xenon-metal halide lamp or any other suitable radiation emitting lamp known in the art. The lamp 11 is controlled by a ballast 14 . Ballast 14 is a known electrical device or chip used in fluorescent and HID fixtures for strating and regulating fluorescent and high intensity discharge lamps. Ballast 14 acts as a power regulating source providing sufficient increasing power for the lamp 11 and further controlling the level of power supplied to the lamp 11 .
The light 20 is preferably positioned within a curing unit. The light guide 20 may be glass, optical fiber or any other suitable light transmissive material known in the art, and is preferably of the liquid-filled type. The light guide 20 includes a light entrance surface 20 a at one end which projects towards the lamp 11 and a light exit/output surface 20 b at the other end which may be directed to a work site or target which contains adhesive material to be light cured. The light exit surface 20 b of the light guide 20 terminates at a single fixture 21 from which the UV radiance is dispersed.
The light guide 20 is supported by a light guide tube receptacle 22 . The light guide tube 22 is suitably mounted on a light guiding mounting plate 23 . Light guide tube 22 has an opening for supportable receipt of the light guide 20 therein. As will be described in more detail below, the light guide 20 acts to at least partially collimate the UV beam E, and the beam is emitted from the light guide 20 via the light exit surface 20 b . As is readily apparent, the light exit surface 20 b is directed to the work site or target which contains adhesive material to be light cured.
Furthermore, a shutter/stop mechanism including a shutter 24 which is generally planar and made of aluminum is affixed to the light guide mounting plate 23 . The shutter 24 is positioned generally parallel to the lamp 11 to selectively control UV energy emanating from the system. The shutter 24 also has an opening 24 a of generally circular configuration located at the center of the shutter. Preferably the shutter 24 is located to selectively control UV energy entering the light guide 20 through the light entrance surface 20 a . The opening and closing of the shutter 24 is described herein. The shutter 24 is movable from a first position, the closed position, wherein a solid portion of the shutter 24 covers the light entrance surface 20 a of the light guide 20 to a second position, the opened position, wherein the shutter opening 24 a is in registry with the light entrance surface 20 a thereby allowing light to pass through the opening 24 a to the light entrance surface 20 a of the light guide 20 . As the UV light beam passes within the light guide 20 , it is emitted from the light guide 20 via the light exit surface 20 b to the worksite containing adhesive material to be cured.
The mechanism for the movement of the shutter 24 is controlled by a solenoid (not shown). Upon appropriate signals the solenoid is activated which in turn moves the shutter 24 from the first position to the second position as discussed above. A timer 15 preferably controls the time period for shutter 24 to remain in the closed and open positions thereby controlling the exposure time of the radiation. The opening and closing of the shutter 24 may be synchronized with a shut off valve 16 in order to preferably synchronize the UV irradiance with a flow of inert gas as will be described in detail below.
The system additionally includes a tube 26 used to feed and disperse inert gas. Preference is given to argon, but gas such as nitrogen, helium or neon are also suitable. The tube 26 includes one end 26 a attached to a source from which the inert gas is fed in the tube 26 and an opposing end including a dispersion nozzle 26 b from which the inert gas is dispersed. The dispersion nozzle 26 b of the tube 26 is integrated with the light exit surface 20 b of the light guide 20 into the single fixture 21 and is designed to disperse the inert gas simultaneously with the light output and/or the UV radiance to the adhesive surface of the work piece.
The regulator 17 preferably controls the rate of flow of the inert gas received in the tube 26 via shut off valve 16 thereby controlling the amount of gas to be dispensed onto the work piece. The shut off valve 16 is preferably solenoid operated to start and stop the flow or movement of the inert gas. In other words, when solenoid is activated, which in turn either opens the valve 16 to start the flow of inert gas in the tube 26 received from the source or shuts off the valve 16 to stop the flow of inert gas in the tube 26 . Also, the operation of the valve 16 is controlled by the timer 15 . The timer 15 is preferably connected to the valve controlling the time period for valve 16 to remain in open and closed positions, thereby controlling the time period of the flow of the inert gas.
In operation, the lamp 11 is activated by the ballast 14 to emanate a focused UV energy beam E through the reflector 13 . This focused UV energy beam falls right on the shutter 24 . The shutter 24 being movable in a second position as discussed above, wherein the shutter opening 24 a is aligned with the light entrance surface 20 a , which allows the UV energy beam to travel into the light guide tube 22 to pass through the light entrance surface 20 a into the light guide 20 . As the UV energy beam is originating from the lamp 11 and passed through the light guide 20 , simultaneously, the inert gas provided by a source is fed into the tube 26 which is encountered by the shut-off valve 16 . The shut-off valve 16 as discussed above is opened to pass the flow of the inert gas into the tube 26 . The shut-off valve 16 causes to initiate the flow or movement of the inert gas through the tube 26 upon the UV energy being emitted. In other words, the relative movement of the inert gas is initiated upon opening of the shutter 24 . Both the tube 26 and the light guide 20 terminate at a common fixture 21 . In other words, the light exit end 20 b of the light guide and the dispersion nozzle 26 b of the tube 26 integrate into the fixture 21 dispensing both the UV energy and the inert gas 21 from the fixture. Therefore, during the curing cycle, both the focused UV energy E and the inert gas are dispersed simultaneously on to the adhesive surface of the worksite. As a result of this operation, material can be cured with the exposure of radiation energy and the dispersion of inert gas simultaneously in order to expel oxygen which would interfere with the curing process. The irradiance levels for spot systems described in the present invention can easily exceed 20 W/cm 2 , whereas, other systems typically produce no more than a couple of W/cm 2 , (i.e., Fusion system electrodeless lamp system).
The devices and the system of the present invention can be used in conjunction with a variety of different photocurable adhesive compositions. For example, UV curable vinyl and (meth)acrylate-containing compositions, which may also be optionally anaerobically curable, may be employed. Such compositions may include urethane-acrylate copolymers and block copolymers such as those disclosed in U.S. Pat. Nos. 3,425,988; 4,295,909; and 4,309,526. Other useful photocurable compositions containing reactive (meth)acrylate components are disclosed in U.S. Pat. Nos. 4,415,604; 4,424,252; and 4,451,523, all to Loctite Corporation.
Photoinitiators which are intended to be active primarily in the ultraviolet (UV) region are incorporated along with the curable component, and which upon exposure to sufficient ultraviolet light initiate photopolymerization of the curable component. Such UV compositions can be used as structural adhesives, potting compounds, gap filling compounds, sealing compounds, conformal coatings as well as other applications known to those skilled in the art.
In addition to the aforementioned adhesive compositions, UV curable silicone compositions are also contemplated as being useful with the present invention. Such compositions contain a curable silicone component and a UV photoinitiator component. Additionally, cyanoacrylate adhesives designed to cure upon exposure to photoirradiation may also be employed.
Examples of commercially available UV curing compositions include Loctite product numbers Adhesive 352, 3321, 3491, 3525 and 3201.
Having described the preferred embodiments herein, it should be further appreciated that various modifications may be made thereto without departing from the contemplated scope of the invention. As such, the preferred embodiments described herein are intended in an illustrative rather than a limiting sense. The true scope of the invention is set forth in the claims appended hereto. | 4y
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ACKNOWLEDGEMENT OF GOVERNMENT SUPPORT
This work was supported in part by National Institutes of Health grants KD06181, T32 DK07296, EY06600, HL39934, and DK20579.
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 07/807,912, filed Dec. 16, 1991, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method of inhibiting nitric oxide formation in warm blooded mammals and, more particularly, to the administration of methylguanidine or dimethylguanidine as an inhibitor of nitric oxide production.
Nitric oxide synthase catalyzes the mixed functional oxidation of L-arginine to L-citrulline and nitric oxide (NO., 1,2). NO. appears to function as either a signaling or an effector molecule depending on the isoform of the enzyme. The constitutive isoform of nitric oxide synthase produces small amounts of NO. which activate guanylate cyclase resulting in the formation of cGMP which mediates endothelium-dependent relaxation (2) and neural transmission (3). NO. is produced in much larger amounts by the cytokine and endotoxin inducible isoform of nitric oxide synthase, and in macrophages functions as an effector molecule which appears to mediate the cytotoxic actions of macrophages on target cells (4). Since NO. is a potent vasodilator and increases blood flow, and since vasoactive agents (such as histamine and bradykinin), which stimulate NO. production increase both blood flow and vascular permeability, NO. may be a candidate for mediating increases in blood flow and vascular permeability induced by diabetes and elevated glucose (5).
Recently, Interleukin-1 (IL-1) has been shown to induce the expression of the cytokine inducible isoform of nitric oxide synthase in pancreatic islets. The production of NO. has been proposed to be the effector molecule which mediates IL-1's inhibitory affects on islet function (6,7). Generation of an IL-1-induced EPR detectable iron-nitrosyl complex, which is prevented by N G -monomethyl-L-arginine (NMMA), has been used to confirm the formation of nitric oxide by islets (8). Also, the protein synthesis inhibitor, cycloheximide, has been shown to block IL-1-induced nitrite formation, cGMP accumulation, and EPR detectable iron-nitrosyl complex formation by islets, thus establishing that IL-1 induces the cytokine inducible isoform of nitric oxide synthase in pancreatic islets (7).
The pathogenesis of diabetic complications has been linked to imbalances in sorbitol, mvo-inositol, and 1,2-diacyl-sn-glycerol metabolism, and to non-enzymatic glycation of cellular and extracellular constituents (5). The glycation link is supported by evidence that aminoguanidine, a nucleophilic hydrazine compound, interferes with the formation of these glycation products and also attenuates the development of several diabetes-induced vascular (5,9), neural (10), and collagen changes (11). Bucala et al. (12) recently reported that quenching of NO. in vitro by glycated albumin is attenuated by aminoguanidine (present during exposure of albumin to glycating agents) and suggested that glycation products may impair endothelium-dependent relaxation by attenuating NO. activity.
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the present invention a novel method of inhibiting nitric oxide formation in warm blooded mammals is provided. The method comprises administering to a warm blooded mammal a small but effective amount of methylguanidine or dimethylguanidine to inhibit nitric oxide production.
It will be understood that pharmaceutically acceptable salts of these compounds, e.g. the HCl and sulfate salts, also can be administered to the mammal.
At the present time the pathogenesis of diabetic complications remains obscure and there is no known medication which has been shown to prevent them. Although diabetic complications are strongly linked to severity of diabetes as reflected by blood sugar levels and glycated hemoglobin, the efficacy of attempts to prevent and/or reverse diabetic complications by efforts to normalize blood sugar levels remains to be documented.
In applicant's copending application Ser. No. 07/807,912, filed Dec. 16, 1991, a method is disclosed whereby aminoguanidine is administered to a warm blooded mammal at doses which inhibit nitric oxide production without producing a substantial elevation in arterial blood pressure. In accordance with the present invention, it has been found that methylguanidine is a potent inhibitor of constitutive and cytokine-induced NO production as manifested by increases in arterial blood pressure when injected intravenously in normal rats. However, in contrast to aminoguanidine, methylguanidine is relatively ineffective in preventing glucose-induced advanced glycation products manifested by the development of fluorescence products characteristic of advanced glycation end products. Thus, it is evident that the prevention by methylguanidine of diabetesinduced vascular dysfunction is attributable to its ability to block NO production rather than blocking advanced glycation end product formation.
DETAILED DESCRIPTION OF THE INVENTION
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter regarded as forming the present invention, it is believed that the invention will be better understood from the following detailed description of preferred embodiments of the invention taken in conjunction with the accompanying drawings in which briefly:
FIG. 1 is a graphical representation which shows the changes in mean arterial blood pressure (MAP) induced by bolus intravenous injections of methylguanidine (MG), aminoguanidine (AG) or N G -monomethyl-L-arginine (NMMA) in which change in MAP is recorded in % increase in pressure above baseline and the dose of the bolus injection is recorded in μmol/kg.
FIG. 2 is a graphical representation which shows the effects of methylguanidine (MG), aminoguanidine (AG) or N G -monomethyl-L-arginine (NMMA) on IL-1-induced nitrite formation by Rin-m5F cells in which the effect on nitrite formation is recorded in % of IL-1βB-induced nitrite formation and the concentration of the test compounds is recorded in μM.
FIG. 3 is a graphical representation which shows the effects of methylguanidine (MG), dimethylguanidine (DMG) and aminoguanidine (AG) on IL-1β-induced nitrite formation by Rin-m5F cells as in FIG. 2.
FIG. 4 is a bar chart which shows the relative development of fluorescence products upon incubation of methylguanidine, aminoguanidine or semicarbazide in glucose-6-phosphate/lysine (G-6-P/Lysine) for six days.
Effects of methylguanidine on constitutive (vascular) nitric oxide synthase activity were assessed by monitoring mean arterial blood pressure (MAP) changes following intravenous injection of methylguanidine in anesthetized, normal rats. The dose responses of methylguanidine, aminoguanidine and NMMA are shown in FIG. 1.
Since methylguanidine contains strong structural similarities to L-arginine and the competitive inhibitor of nitric oxide synthase, viz. NMMA, in that these compounds contain two chemically equivalent guanidine nitrogen groups, the effects of methylguanidine on IL-1β-induced formation of nitrite and cGMP by Rin m5F cells were examined and compared to the effects of NMMA in similar tests (FIG. 2). Also in similar tests, methylguanidine and its close analog, dimethylguanidine, were each compared to the effects of aminoguanidine (AG) (FIG. 3). The Rin m5F cell line is an insulinoma cell line of the rodent β-cell that has been shown to contain the cytokine-inducible isoform of nitric oxide synthase. FIGS. 2 and 3 demonstrate the dose response of methylguanidine, dimethylguanidine, aminoguanidine and NMMA or AG on IL-1β-induced formation of nitrite (an oxidation product of nitric oxide) from Rin m5F cells incubated for 18 hrs with 5 units/ml IL-1β± the indicated concentrations of methylguanidine, dimethylguanidine, aminoguanidine and NMMA or AG.
The effects of methylguanidine on glycation were assessed by measuring the development of fluorescence products upon its incubation in glucose-6-phosphate/lysine and compared to the corresponding effects of aminoguanidine and semicarbazide. The results are shown in FIG. 4 and indicate that methylguanidine is relatively ineffective (compared to aminoguanidine and semicarbazide) in preventing glucose-induced glycation products as manifested by the development of fluorescence products which are characteristic of glycation end products.
In order to further illustrate the invention, the following detailed EXAMPLES were carried out although it should be understood that the invention is not limited to these specific EXAMPLES or the details described therein. The results obtained in these EXAMPLES are shown in Tables 1 to 5 and the accompanying FIGS. 1 to 4.
EXAMPLE I
This example illustrates a method to prevent diabetes-induced vascular dysfunction using methylguanidine to inhibit nitric oxide synthase.
MATERIALS AND METHODS
Animal Protocols
All rats used in these tests were housed and cared for in accordance with the guidelines of the University Committee for the Humane Care of Laboratory Animals and in accordance with NIH guidelines on laboratory animal welfare. Rats were housed individually, allowed food (standard rat chow; Ralston Purina, Richmond, IN) and water ad libitum, and were on a 12 hour light/dark cycle. Male, Sprague-Dawley rats initially weighing 225-250 g were divided into four groups: group 1, untreated controls; group 2, methylguanidine (mg)-treated controls; group 3, untreated diabetics; and group 4, mg-treated diabetics. Diabetes was induced by intravenous injection of 45 mg/kg body weight streptozotocin (Sigma Chemical Co., St. Louis, MO) using ketamine anesthesia. Methylguanidine hydrochloride (Sigma Chemical Co.) was administered subcutaneously once daily at a dose of 25 mg/kg body weight. In addition, control rats were given water containing 2.5 g/L methylguanidine while diabetic rats were given water containing 1 g/L. Water consumption was monitored weekly for all rats.
Body weights were measured weekly, nonfasting morning plasma glucose levels were assessed 3 days after injection of streptozotocin (to ensure induction of diabetes), then biweekly thereafter using the conventional glucose oxidase method of Lowry and Passoneau (14). After 4 weeks, all rats were placed into individual metabolic cages for 24 hours to determine food consumption (g/100 g body weight/24 hr) and urine output (ml/kidney/24 hr). A sample of urine was stored at -70° C. for determination of urinary albumin excretion (see below). Five weeks after induction of diabetes, rats were used for the permeability and blood flow studies detailed below.
Test Protocol
Regional vascular albumin permeation was quantified by use of an isotope dilution technique based on the injection of bovine serum albumin (BSA) labeled with 2 different iodine isotopes, 131 I and 125 I (15-17). 125 I-BSA was used to quantify vascular albumin filtration after 10 min of tracer circulation, while 131 I-BSA served as a plasma volume marker for correction of 125 I-BSA tissue activity for tracer contained within vessels.
Preparation of radiolabeled tracers. Purified monomer BSA (20 mg) was iodinated with 1 mCi of 131 I or 125 I (NEN Research Products, Boston, MA) by the iodogen method as previously described (15). 57 Co-EDTA was prepared as previously described (15, 16) and 46 Sc-microspheres (10 μm diameter) were used to assess regional blood flow as detailed below.
Surgical Procedures. Rats were anesthetized with inactin (Byk Gulden, Konstanz, FRG) (˜100 mg/kg body weight injected i.p.), and core body temperature maintained at 37±0.5° C. using heat lamps, a 37° C. surgical tray, and a rectal temperature probe. The left femoral vein, left iliac artery, right subclavian artery, and right carotid artery were cannulated with polyethylene tubing (0.58 mm i.d.) filled with heparinized saline (400 U heparin/ml). The femoral vein cannula was used for tracer injection and the subclavian artery cannula was connected to a pressure transducer for blood pressure monitoring. The left iliac artery was connected to a 1 ml syringe attached to a Harvard Model 940 constant withdrawal pump preset to withdraw at a constant rate of 0.055 ml/min. The tip of the cannula in the right carotid artery was placed in the left ventricle of the heart and was used for injection of radiolabeled microspheres. The trachea was intubated and connected to a small rodent respirator for continuous ventilatory support.
Test Procedure
At time 0, 125 I-albumin (in 0.3 ml of saline) and 57 Co-EDTA (˜0.1μCi in 0.1 ml of saline) were injected i.v. and the withdrawal pump was started simultaneously. Eight min after time 0, 0.2 ml of 131 I-BSA was injected and 1 min later, the 46Sc-microspheres were injected slowly over ˜30 sec. At the 10 min mark, the heart was excised to stop all blood flow, the withdrawal pump was stopped simultaneously, and various tissues were sampled for gamma spectrometry.
Both kidneys, bladder, and connecting ureters were removed. Eyes were dissected as previously described (15, 16) and tissues from both eyes were pooled prior to gamma spectrometry. All tissue samples and arterial plasma samples were weighed, then counted in a gamma spectrometer interfaced with a Hewlett-Packard 1000A computer in which the data were corrected for background and stored for subsequent analysis.
Data Analysis
A quantitative index of 125 I-BSA tissue clearance was calculated as previously described (15, 16, 17) and expressed as μg plasma/g tissue wet weight/min. Very briefly, 125 I-BSA tissue activity was corrected for tracer contained within the tissue by multiplying 125 I-BSA activity in the tissue by the ratio of 125 I-BSA/ 131 I-BSA activities in the arterial plasma sample obtained at the end of the test. The vascular-corrected 125 I-BSA tissue activity was divided by the time-averaged 125 I-BSA plasma activity (obtained from a well mixed sample of plasma taken from the withdrawal syringe) and by the tracer circulation time (10 min) and then normalized per g tissue wet weight.
Glomerular filtration fate (GFR) was calculated as previously described (18). To calculate regional blood flows, the total activity of 46 Sc in the retina was divided by the total activity of 46 Sc in the reference blood sample obtained from the withdrawal syringe, then multiplied by the pump withdrawal rate, and expressed as ml/g tissue wet weight per minute (19).
Preparation of advanced glycosylation end products
Lysine-derived advanced glycosylation products were prepared as described by Bucala et al. (12) by incubating 100 mM concentrations of glucose-6-phosphate and L-lysine in 0.2 M sodium phosphate buffer, pH 7.4. The incubations were maintained sterile, and were kept in the dark at room temperature for ˜6 days, at which time relative fluorescence was measured as an index of glycation using a Perkin-Elmer LS-5B luminescence spectrometer with excitation at 370 nm and emission at 440 nm. Samples were diluted 1:11 with saline prior to spectrometry. The ability of 10 and 100 mM concentrations of methylguanidine, aminoguanidine, or semicarbazide to inhibit the glycation process was compared in two separate tests (FIG. 4).
Blood Pressure Measurement
Systolic blood pressure was measured at weekly intervals in conscious rats using the tail-cuff method (20, 2). Animals were adapted to the procedure initially by placing them in a restrainer and inflating the sphygmomanometer several times. Blood pressure also was obtained from the iliac artery cannula in anesthetized rats during the permeability studies.
Effects of bolus injections of methylguanidine on mean arterial blood pressure
Normal male, Sprague-Dawley rats weighing 250-300 g were anesthetized with 100 mg/kg body weight inactin, followed by 0.1 ml/kg body weight d-tubocurarine chloride, the left femoral vein (for tracer injection) and right iliac artery (for monitoring blood pressure) were cannulated with polyvinyl tubing (0.8×0.5 mm) filled with heparinized saline, and the trachea was cannulated and connected to a small rodent respirator for continuous ventilatory support. Following stabilization of arterial pressure, increasing amounts (3.1 and 50 μmol/kg body weight) of methylguanidine or N G -monomethyl-L-arginine (NMMA) were injected intravenously in a volume of 0.5 ml in separate animals and the peak pressure increase was recorded using a Gould RS 3200 recorder. Results were expressed as a percent increase in pressure above baseline.
Statistical Analysis
Data are expressed as mean ±1SD. An analysis of variance was performed using the SAS general linear models procedure. To reduce potential type 1 errors related to multiple comparisons, overall differences among groups for each parameter were preliminarily assessed by the Van Der Waerden test. If statistically significant differences (at p<0.05) were indicated among groups for a given parameter, pair-wise comparisons were assessed by least square means following a nonparametric (rank order) Blom transformation of all data.
EXAMPLE II
This example illustrates the effects of methylguanidine on IL-1β-induced nitrite formation by Rin m5F cells (FIG. 2). Rin m5F cells, obtained from the Washington University Tissue Culture Support Center, were removed from growth flasks (55-80 million cells/flask) by trypsin/EDTA treatment, and aliquoted into 1 ml Petri dishes (1-2 million Rin m5F cells per condition). Cells were incubated for 18 hrs (under an atmosphere of 95% air and 5% CO 2 ) in 1 ml of complete CMRL-1066 tissue culture media (CMRL supplemented with 10% heat-inactivated, fetal bovine serum, 2 mM L-glutamine, 50 units/ml penicillin, and 50 μg/ml streptomycin), or complete CMRL-1066 supplemented with methylguanidine (MG), aminoguanidine (AG) or NMMA. Following incubation, the supernatant was removed and nitrite was determined on 100 μl aliquots by conventional procedures as previously described (8,13). The results are expressed as the % of IL-1 induced nitrite formation, and are the mean ± SEM of 4 individual tests containing 3 replicates per test. The results demonstrate that both AG and NMMA are ˜10 fold more potent than MG at inhibiting nitric oxide formation by the cytokine inducible isoform of nitric oxide synthase.
EXAMPLE III
The effects of each of methylguanidine, 1,1-dimethylguanidine and aminoguanidine on IL-1β-induced nitrite formation by Rin m5F cells were tested by the procedures described in EXAMPLE II and the results are shown in FIG. 3. The results demonstrate the following order of potency, AG>DMG>MG, for inhibiting the cytokine inducible isoform of nitric oxide synthase.
Tables 1 to 5, below, and the accompanying FIGS. 1 to 4 record the results obtained in the foregoing EXAMPLES. These results indicate that methylguanidine and dimethylguanidine are potent inhibitors of constitutive and cytokine-induced NO production. This is manifested by increases in mean arterial blood pressure by methylguanidine when injected intravenously in normal rats as shown in FIG. 1 and by inhibition of IL-1β-induced increases in nitrite in rodent insulinoma cells with methylguanidine and dimethylguanidine as shown in FIGS. 2 and 3, respectively. Since methylguanidine is relatively ineffective (in contrast t aminoguanidine) in preventing glucose-induced glycation products (manifested by the development of fluorescence products characteristic of advanced glycation end products (FIG. 4), the prevention by methylguanidine of diabetes-induced vascular dysfunction is believed to be attributable to its ability to block NO production. Methylguanidine and its close analog, dimethylguanidine, thus should be useful for prevention of diabetic complications as well as inflammatory and immunological diseases in which increased NO production is involved.
TABLE 1______________________________________Effects of diabetes and methylguanidine on bodyweights, plasma glucose and water consumption. control + diabetic + control mg diabetic mg______________________________________number of rats 10 11 14 18body weights(g)initial 249 ± 20 256 ± 16 250 ± 19 248 ± 18week 2 326 ± 25 300 ± 31 297 ± 23 271 ± 23week 4 375 ± 41 351 ± 37 334 ± 45 294 ± 50plasma glucose 130 ± 15 131 ± 28 419 ± 120 420 ± 87(mg/dL)hematocrit (%) 43 ± 2 42 ± 1 42 ± 1 42 ± 2blood pressure(mm Hg)conscious 125 ± 18 121 ± 7 123 ± 5 126 ± 5anesthetized 118 ± 14 114 ± 14 120 ± 16 121 ± 14water 46 ± 6 32 ± 9 108 ± 42 93 ± 53consumption(ml/day)______________________________________
TABLE 2__________________________________________________________________________Effects of diabetes and methylguanidine (mg)on .sup.125 I-albumin permeation.sup.a control control + mg diabetic diabetic + mg__________________________________________________________________________number of rats 10 8 11 9eyeanterior uvea 266 ± 77.sup.b 359 ± 146 623 ± 109.sup.a 370 ± 60.sup.bposterior uvea 328 ± 106 312 ± 101 742 ± 134.sup.a 358 ± 108retina 47 ± 12 61 ± 11 116 ± 30.sup.a 55 ± 18sciatic nerve 47 ± 13 47 ± 10 121 ± 22.sup.a 50 ± 10aorta 62 ± 20 60 ± 18 155 ± 37.sup.a 85 ± 41kidney 727 ± 239 714 ± 214 1011 ± 265.sup.c 738 ± 169lung 1805 ± 532 1656 ± 454 1405 ± 324.sup. 1,498 ± 487diaphram 201 ± 75 190 ± 27 210 ± 61.sup. 216 ± 46heart 521 ± 135 731 ± 269 534 ± 62 599 ± 68brain 5 ± 3 4 ± 3 .sup. 5 ± 2 6 ± 4__________________________________________________________________________ .sup.a μg plasma/g wet weight/min; see Methods in EXAMPLE I for detail of test procedure. .sup.b mean ± SD Significantly different from untreated controls by Student's t test: .sup.a p < 0.001; .sup.b p < 0.05; .sup.c p < 0.01.
TABLE 3__________________________________________________________________________Effects of diabetes and methylquanidine (mg)on regional blood flows* anterior posterior sciatic (n) uvea uvea retina nerve kidney__________________________________________________________________________control (10) 2.0 ± 0.6 3.4 ± 0.6 0.43 ± 0.02 0.06 ± 0.02 6.5 ± 0.3.sup.control + mg (8) 2.4 ± 0.5 3.3 ± 0.6 0.45 ± 0.07 0.07 ± 0.03 4.8 ± 0.3.sup.adiabetic (10) .sup. 2.7 ± 0.3.sup.b .sup. 4.2 ± 0.5.sup.b .sup. 0.57 ± 0.08.sup.a .sup. 0.09 ± 0.01.sup.a 6.0 ± 0.4.sup.cdiabetic + mg (9) 2.3 ± 0.6 3.9 ± 0.6 0.45 ± 0.04 0.06 ± 0.02 5.8 ± 0.3.sup.a__________________________________________________________________________ *ml/min/g wet weight; values are mean ± 1SD measured using radiolabele microspheres (˜10 μm diameter) Significantly different from controls by Student's t test; .sup.a p < 0.001; .sup.b p < 0.005; .sup.c p < 0.01
TABLE 4______________________________________Effects of diabetes and methylguanidine (mg)on GFR* (n) per whole kidney per g kidney______________________________________control (10) 1.33 ± 0.19 0.85 ± 0.07control + mg (8) 1.53 ± 0.29 0.87 ± 0.08diabetic (10) .sup. 1.81 ± 0.25.sup.a 0.92 ± 0.14diabetic + mg (9) 1.59 ± 0.15.sup.b,c 0.85 ± 0.09______________________________________ *ml/min; values are mean ± 1SD measured using radiolabeled .sup.57 CoEDTA Significantly different from controls by Students' ttest: .sup.a p < 0.001; .sup.b p < 0.005 Significantly different from diabetics by Students' ttest: .sup.c p < 0.0
TABLE 5______________________________________Effects of diabetes and methylguanidine (mg)on tissue sorbitol and myo-inositol control + diabetic +control mg diabetic mg______________________________________number of 7 8 11 9ratsretinasorbitol .sup. 102 ± 16.sup.a 102 ± 31 933 ± 275 533 ± 265myo- 1613 ± 516 1529 ± 187 1564 ± 452 1513 ± 402inositolsciaticnervesorbitol 183 ± 41 194 ± 75 1999 ± 334 1234 ± 710myo- 3943 ± 526 4263 ± 1587 3444 ± 639 3308 ± 792inositolerythro-cytessorbitol 6 ± 1 6 ± 2 44 ± 9 40 ± 8myo- 131 ± 47 104 ± 19 109 ± 20 103 ± 19inositol______________________________________ .sup.a values are mean ± SD; see Methods in EXAMPLE I for test procedures
The methylguanidine and dimethylguanidine inhibitors of nitric oxide formation described herein can be used for administration to warm blooded mammals by conventional means, preferably in formulations with pharmaceutically acceptable diluents and carriers. The amount of the active inhibitor to be administered must be an effective amount, that is, an amount which is medically beneficial but does not present toxic effects which overweigh the advantages which accompany its use. It would be expected that the adult human daily dosage would normally range upward from about one milligram per kilo of body weight of the drug. A suitable route of administration is orally in the form of capsules, tablets, syrups, elixirs and the like, although parenteral administration also can be used, e.g. intraveneously, intraperitoneally or subcutaneously. Intraveneous administration of the drug in aqueous solution such as physiologic saline is illustrative. Appropriate formulations of the drug in pharmaceutically acceptable diluents and carriers in therapeutic dosage form can be prepared by reference to general texts in the field such as, for example, Remington's Pharmaceutical Sciences, Ed. Arthur Osol. 16th ed., 1980, Mack Publishing Co., Easton, PA.
Various other examples will be apparent to the person skilled in the art after reading the present disclosure without departing from the spirit and scope of the invention. It is intended that all such examples be included within the scope of the appended claims.
References cited in parenthesis in the disclosure are appended hereto as follows:
1. D. J. Stuehr, H. J. Cho, N. S. Kwon, M. F. Weise, C. F. Nathan, Proc. Natl. Acad. Sci. USA 88, 7773 (1991).
2. S. Moncada, R. M. J. Palmer, E. A. Higgs, Pharmacol. Reviews 43, 109 (1991).
3. J. Garthwaite, Trends Neurol. Sci. 14:60 (1991).
4. J. B. Hibbs, Jr., et al., in Nitric Oxide from L-Aroinine: a Bioregulatory System, S. Moncada and E. Higgs, Eds. Elsevier, New York, (1990) pp 189-223.
5. G. Pugliese, R. G. Tilton, J. R. Williamson, Diabetes/Metabolism Reviews 7, 35 (1991).
6. C. Southern, D. Schulster, I. C. Green, Febs Lett. 276, 42 (1990).
7. J. A. Corbett, J. L. Wang, M. A. Sweetland, J. R. Lancaster, Jr., M. L. McDaniel, Biochemical J. (submitted).
8. J. A. Corbett, J. R. Lancaster, Jr., M. A. Sweetland, M. L. McDaniel, J. Biol. Chem. 266, 21351-21354 (1991).
9. J. R. Williamson et al., Diabete & Metab. 16, 3369 (1990). T. Soulis-Liparota, M. Cooper, D. Papazoglou, B. Clarke, G. Jerums, Diabetes 40, 1328 (1991).
10. M. Kihara et al., Proc. Natl. Acad. Sci. USA 88, 6107 (1991).
11. M. Brownlee, A. Cerami, H. Vlassara, N. Engl. J. Med. 318, 1315 (1988). M. Brownlee, H. Vlassara, A. Kooney, P. Ulrich, A. Cerami, Science 232, 1629 (1986).
12. R. Bucala, K. J. Tracey, A. Cerami, J. Clin. Invest. 87, 432 (1991).
13. L. C. Green et al., Anal. Biochem. 126, 131 (1982).
14. O. H. Lowry, J. V. Passoneau (1972) A Flexible System of Enzymatic Analysis. Orlando: Academis Press.
15. R.G. Tilton, K. Chang, G. Pugliese, D. M. Eades, M.A. Province, W. R. Sherman, C. Kilo, J. R. Williamson, Diabetes 38, 1258-1270 (1989).
16. G. Pugliese, R. G. Tilton, A. Speedy, K. Chang, M. A. Province, C. Kilo, J. R. Williamson, Metabolism 39, 690-697 (1990).
17. G. Pugliese, R. G. Tilton, K. Chang, A. Speedy, M. Province, D. M. Eades, P. E. Lacy, C. Kilo, J. R. Williamson, Diabetes 39, 323-332 (1990).
18. Y. Ido, R. G. Tilton, K. Chang, and J. R. Williamson, Kidney Int., In press, 1992.
19. G. Pugliese, R. G. Tilton, A. Speedy, E. Santarelli, D. M. Eades, M. A. Province, C. Kilo, W. R. Sherman, J. R. Williamson, Diabetes 39 312-322 (1990).
20. M. J. Fregly, J. Lab. Clin. Med. 62, 223-230 (1963).
21. J. M. Pfeffer, M. A. Pfeffer, E. D. Frohlich, J. Lab. Clin. Med. 78, 957-962 (1997 ). | 4y
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method for driving mechanisms assembled from multiple modules of the same type and various constructions of redundant modular robots produced therefrom, which are suited for various tasks in places that are not easily accessible to operators and mobile rescue machine.
[0003] 2. Description of the Prior Art
[0004] In this description, the conventional vocabulary used in the technical field of robotics will be used in general. By “robot” is meant an articulated mechanical system constituted by a connection of at least two modules, with which is associated a control unit.
[0005] By the term “end-effector” is meant any system, active or passive, allocated normally at the distal end of the robot construction, adapted to the application envisaged, for example a gripper, a point, a tool, etc.
[0006] By the term “position” is meant a position and/or an orientation in space, of the end-effector or of a mark connected to an element considered with respect to a reference mark.
[0007] By the term “modular” is meant a repetition of units having the same architecture, these units able to be identical or different by their dimensions. Auxiliary units of a different type may, in some cases, be inserted between the modules.
[0008] Industrial robots are constructed by bodies or members connected between them such that to permit a rotation or a translation of one member with respect to other neighboring members. The members differ from each other in order to specialize the robot to a given task. Normally, robots have mechanical complexity and high cost. Moreover, they are not redundant and are therefore incapable of functioning correctly in case of more complicated robot configurations or motions.
[0009] The redundant robots have been conceived more recently for intervening in inconvenient or quasi-closed environments. Redundant robot means a robot with surplus numbers of modules with respect to what is required and sufficient to position the robot end-effector in the space. The redundant modules provide additional mobility to the robot for positioning the end-effector in several different manners. Redundancy can improve robot versatility in complex environments, where the extra modules can be used for obstacle avoidance, or to overcome deficiencies arising from kinematical, mechanical, and other design limitations inherent in non-redundant manipulators. Because of their highly articulated structures, hyper-redundant robots are superior for applications and operation in very complicated and unusual environments.
[0010] Several prior art techniques that are used for driving multiple-module mechanisms and producing redundant modular robots are known. They are analogous in morphology and operation to “snakes,” “elephant trunks,” “tentacles” or “earthworms”.
[0011] The first technique is referred as cable (wire rope) driven robots where the articulated robot modules are individually driven and controlled by cable systems. Diverse modifications of this concept are known, but all they possess various types of deficiencies such as partial or total breakdown of the robot in the case of cable breakage, non-controllable robot in case of failure of a transmission, limited or very limited working space, need of plurality of driving motors associated with respective degrees of freedom, which requires also very complicated control system for all motors.
[0012] A second prior art technique referred as multiple rotation robot mechanism is known that avoids the use of cables (wire ropes) but involves a lot of driving motors, which result in higher own robot weight and complex control system.
[0013] A third prior art technique referred as deformation in a plane is known that also avoids the limitations involved by using the cables (wire ropes) but also employs relatively high number of driving motors, which give higher robot weight and complex control system.
[0014] All pointed prior art techniques have the disadvantage of using large number of motors with respective multi-axes control system, the complexity of which is increased due to the need of synchronous operation of different subsets of motors. Hence, the existing solutions so far accommodate limitations both in terms of complexity and costs.
[0015] Therefore, a need exists in the art of driving modular redundant robots for an improved technique for extremely simplified driving of multiple-module mechanisms, which are either identically repetitive or with some dimensional modifications, each module itself being constructed of repetitive elements, and producing modular redundant robots therefrom in order to overcome the limitations of the prior art.
[0016] An object is to provide redundant modular robots, the construction of which is expandable and reconfigurable according to the type of task to be accomplished and which is driven by a single irreversible motor that requires a very simple single-axes control system.
[0017] Another object is to provide redundant modular robots, which are easy to assemble and disassemble because of their simple structure and the low number of used components.
[0018] Still another object is to provide redundant modular robots, which are relatively simple, lightweight and economical to manufacture from standard off-the-shelf components.
[0019] In accordance with the present invention, a method for driving multiple-module mechanisms by a single motor and redundant modular robots produced therefrom can be carried out. The method is based on a very simplified approach inspired by the functioning of the bodies of animals, which have only one source of energy—their heart, which provides blood to all muscles of the body. Following this principle, the method assumes only one motor that is driving all moving parts and multiple-module mechanisms in a robot. According to this method, an irreversible motor is the only source of energy transferred to all mechanisms. As the produced mechanical energy cannot be easily stored for future use, it must be utilized directly after being delivered to the said multiple-module mechanisms of the said modular robot.
[0020] A flexible shaft transports the motor rotation to the mechanisms inside all multiple modules. In order to distribute selectively the energy to a desired destination a kit of electromagnetic clutches and transmission wheels is used. When an electromagnetic clutch is powered-on the flexible shaft rotation is translated to the shaft of the destination mechanism through a respective transmission wheel. After a desired angle of rotation of the so driven said mechanism is achieved, the electromagnetic clutch is switched-off. An electromagnetic break can be included when it is desired that the said mechanism remain at this said desired angle of rotation.
[0021] To allow both positive and negative said desired angle of rotation of the said mechanism, a second complementary electromagnetic clutch is attached appropriately to another complementary said transmission wheel. The operation of the said complementary electromagnetic clutch and said complementary transmission wheel is provided in the same way.
[0022] The method for driving multiple-module mechanisms by a single irreversible motor using the above mentioned principle requires a simple control system, the first part of which has the main task to change and stabilize the angular speed of the motor. The second part of the said control system employs simple on-off logic control and can be implemented on variety of commercial programmable controllers or can be embedded in the redundant modular robot produced therefrom.
[0023] The present invention is further directed to a redundant modular robot produced from multiple modules driven by a single motor. This apparatus is based on the very simplified said method for driving multiple-module mechanisms using only a single irreversible motor without the need of multiple motors, which drive separate robot modules and mechanisms, or groups of such mechanisms.
[0024] In the preferred embodiment, a redundant modular robot, produced from multiple-module mechanisms driven by a single irreversible motor, can achieve the above-mentioned objects. There are various possible constructions of the said multiple link mechanisms and various possible configurations of said redundant robots produced therefrom. These two types of varieties will be further explained as detailed descriptions of several preferred embodiments.
[0025] The implementation of said apparatus is first disclosed by the general description of a redundant modular robot comprising the following main structural components:
a) a plurality of connected to each other robot modules driven by the said flexible shaft, each of which has the same internal construction, performs the same type of motion, and articulates around a common inter-link shaft with the next adjacent module forming a chain of multiple modules; b) a driving motor the body of which is fixed to the proximal module of said chain of multiple modules, the shaft of which is connected to the proximal side of said flexible shaft, the distal side of which is extended up to the desired number of modules in the redundant robot construction; c) an end-effector connected to the distal module in the said chain of multiple modules for performing desired manipulations of the redundant robot; d) if a manipulator arm or “elephant trunk” configuration of the redundant robot is desired, the distal module of said chain of modules is fixed on a base installed to appropriate working space, otherwise the redundant robot can perform motions like “snake” or “earthworm”.
[0030] The implementation of said apparatus is further disclosed by the general description of one of the all multiple modules comprising a mechanism with nearly the same types and number of interconnected components, namely:
a) a primary driving wheel fixed to the said flexible shaft for transferring the rotation of the driving motor to the mechanism of said module; b) a pair of primary transferring wheels each of which is coupled to the said primary driving wheel such that the said primary transferring wheels have opposite directions of rotation to each other; c) a pair of electromagnetic clutches, the body of which is fixed to the body of said module by a fixture, and the shaft of each said electromagnetic clutch is fastened to one of said primary transferring wheels; d) a pair of secondary transferring wheels each of which is fixed to the moving part of the respective said electromagnetic clutch, such that when the said electromagnetic clutch is powered-on, the said secondary transferring wheel receives the rotation from the primary transferring wheel; e) a secondary driving wheel, which is fixed to the said inter-link shaft that connects two adjacent said modules of the robot, and is also coupled to both said secondary transferring wheels such that receives the rotation from one of said secondary transferring wheels and rotates through the said inter-link shaft the said next adjacent module in the said chain of modules; f) an encoder the body or which is fixed to the body of said module such that the angle of rotation of the said inter-link shaft is measured by the said encoder; g) an electromagnetic break the body of which is fixed to the body of said module such that when the said break is powered on the angle of rotation between the said module and its said adjacent module is kept fixed for providing a desired configuration of the robot.
[0038] One advantage of the present invention is that it provides a method for driving multiple-module mechanisms by a single irreversible motor and redundant modular robots produced therefrom, whereby the limitations as encountered by the prior art can be overcome. This method can be used in a variety of mechanical constructions where modularity and simplicity are aimed.
[0039] Other advantage of the present invention is that it provides a method for driving mechanisms assembled from multiple modules of the same type and redundant modular robots produced therefrom such that the modules of which are either identically repetitive or with some dimensional modifications, each module itself being constructed of repetitive elements.
[0040] Another advantage is that it provides redundant modular robots, the construction of which can be expanded and reconfigured according to the type of task to be accomplished.
[0041] Still another advantage is that it provides redundant modular robots, which use low variety of components that are easy to assemble and disassemble that makes the robots relatively simple and economical to manufacture and maintain.
[0042] Further advantage is that it provides redundant modular robots with relatively lightweight structure that has potentially higher payload capacity.
[0043] Still further advantage is that it provides redundant modular robots with simplified control system for independent control of all robot modules employing dominantly on-off logic control actions to the electromagnetic clutches and breaks and simple single-axis motor regulator.
[0044] These and other objects and advantages of the present invention will be apparent from the detailed description below taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045] FIG. 1 presents the kinematics structure of the first preferred embodiment of a redundant modular robot, which performs motions like a “snake”, in which the mechanisms in the modules are based on worm gearing.
[0046] FIG. 2 presents the kinematics structure of the second preferred embodiment of a redundant modular robot, which performs motions also like a “snake”, but in which the mechanisms in the modules are based on bevel gearing.
[0047] FIG. 3 presents the kinematics structure of the third preferred embodiment of a redundant modular robot, which performs motions like a single-arm robot manipulator, in which the mechanisms in the modules are based on worm gearing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0048] The present invention provides a method for driving multiple-module mechanisms by a single irreversible motor and redundant modular robots produced therefrom. They are created on the base of the essential concept presented below.
[0049] A first embodiment of the redundant modular robot of the invention, as seen on FIG. 1 , has a plurality of connected to each other robot modules 10 , 20 , 30 , etc. driven by a flexible shaft 1 . Each of the modules 10 , 20 , 30 , etc., has the same internal construction and performs the same type of motion. A pair of two adjacent modules, for example 10 and 20 , or 20 and 30 , articulates around a common inter-link shaft 8 such that all modules 10 , 20 , 30 , etc., form a chain of multiple modules.
[0050] The driving motor 100 is fastened to the body of the proximal module 10 of said chain of multiple modules. The output shaft of the motor 100 is connected to the proximal side of said flexible shaft 1 . The flexible shaft 1 is extended up to a length corresponding to the desired number of modules 10 , 20 , 30 , etc., in the redundant robot construction and transfers the torque produced by the motor to all said modules 10 , 20 , 30 , etc., as well as possibly the end-effector, articulated to the distal module of the said chain of modules (not shown on FIG. 1 ). This end-effector performs the desired manipulations of the redundant robot; therefore its construction is application dependent and is out of the scope of the present invention.
[0051] Refering to FIG. 1 , the proximal module 10 is not fastened to any device; therefore appropriate “free” motion of the proximal end of the redundant modular robot can be achieved by respective programming of the robot control unit (not shown as irrelevant to the present invention). This type of motion is characteristic to some animals' motions; hence the structure on FIG. 1 corresponds to a “snake” robot.
[0052] The implementation of each module 10 , 20 , 30 , etc., is further disclosed by the description of the internal mechanism of these modules, comprising the same types and number of interconnected components. Referring again to FIG. 1 , a primary driving wheel 2 is fixed to the said flexible shaft 1 and transfers the rotation from the driving motor 100 to the mechanism of said module. A pair of primary transferring wheels 3 a and 3 b coupled to both sides of the primary driving wheel 2 such that primary transferring wheel 3 b rotates at opposite direction to the 3 a wheel. These primary driving wheels 3 a and 3 b rotate permanently as the driving motor 100 and the flexible shaft 1 do.
[0053] Pair of electromagnetic clutches 5 a and 5 b is provided for switching one of the opposite directions of rotations further to the mechanism. The body of the clutches 5 a and 5 b are fastened to the body of said module through a fixture 7 . The shaft of clutch 5 a is fixed to the primary transferring wheel 3 a and the shaft of clutch 5 b is fixed to the primary transferring wheel 3 b . When one of the clutches 5 a and 5 b is activated by powering-on the respective direction of rotation if propagated further to the mechanism. If none of the clutches 5 a and 5 b is activated no rotation is transferred to the mechanism and the respective module does not change its pose.
[0054] Pair of secondary transferring wheels 4 a and 4 b is provided for receiving the rotation from the primary transferring wheels 3 a and 3 b respectively. Each of these wheels 4 a and 4 b is fixed to the moving part of the respective electromagnetic clutch 5 a or 5 b. When clutch 5 a is activated, the secondary transferring wheel 4 a receives the rotation from primary transferring wheel 3 a. When clutch 5 b is activated, the secondary transferring wheel 4 b receives the rotation from primary transferring wheel 3 b.
[0055] Secondary driving wheel 4 c is coupled to both secondary transferring wheels 4 a and 4 b such that receives the rotation from one of 4 a or 4 b. This secondary driving wheel 4 c is fixed to the said inter-link shaft 8 that connects the pair of two adjacent modules of the robot, for example 10 and 20 , or 20 and 30 . As the shaft 8 is fastened to the body of the next module 20 and articulates at the body's edge of module 10 , when the secondary driving wheel rotates, the torque is transferred to swivel the module 20 at a desired relative angle to module 10 . The same happens for each successive pair like modules 20 and 30 , etc. The encoder 9 , the body or which is fixed to the body of module 10 (or 20 , 30 , etc.) and the shaft of which is attached to shaft 8 measures this relative angle. An electromagnetic break 6 is provided to keep this angle fixed for performing a desired pose of the robot. The body of the break 6 is fixed to the body of module 10 (or 20 , 30 , etc.) and the shaft is fastened to the inter-link shaft 8 .
[0056] In order to achieve higher torques for the plurality of modules 10 , 20 , 30 , etc., and their mechanisms, the triple of wheels 3 a , 2 and 3 b form a worm-type gear. At the same time the triple of wheels 4 a , 4 b and 4 c can constitute for example normal teeth-wheel gear with appropriate ratio.
[0057] As the kinematical scheme and principle of operation of the first embodiment mechanism can be designed in a variety of concrete mechanical constructions, they are considered as not deviating from the spirit of the present invention and therefore embraced by it.
[0058] A second embodiment of the redundant modular robot of the invention is illustrated on FIG. 2 . For convenience of the explanation and easy comparisons of the schemes all participating components have the same indices. The main difference between the first and second preferred embodiment is in the way of implementing the internal mechanism of the multiple modules. Therefore the general structure of the redundant modular robot is the same as in the first embodiment. It is presented here for keeping the completeness of the description.
[0059] The redundant modular robot has a plurality of connected to each other modules 10 , 20 , 30 , etc. driven by a flexible shaft 1 . Each of the modules 10 , 20 , 30 , etc., has the same internal construction and performs the same type of motion. A pair of two adjacent modules, for example 10 and 20 , or 20 and 30 , articulates around a common inter-link shaft 8 divided in two parts 8 a and 8 b , such that all modules 10 , 20 , 30 , etc., form a chain of multiple modules.
[0060] The driving motor 100 is fastened to the body of the proximal module 10 of said chain of multiple modules. The output shaft of the motor 100 is connected to the proximal side of said flexible shaft 1 . The flexible shaft 1 is extended up to a length corresponding to the desired number of modules 10 , 20 , 30 , etc., in the redundant robot construction and transfers the torque produced by the motor to all said modules 10 , 20 , 30 , etc., as well as possibly the end-effector, articulated to the distal module of the said chain of modules (not shown on FIG. 2 ). Referring to FIG. 2 , as the proximal module 10 is not fastened to any device, the structure on FIG. 2 corresponds also to a “snake” robot.
[0061] The particular implementation of each module 10 , 20 , 30 , etc., in this second embodiment is further disclosed by the description of the internal mechanism of these modules. Referring again to FIG. 2 , a driving wheel 2 is fixed to the said flexible shaft 1 and transfers the rotation from the driving motor 100 to the mechanism of said module. A pair of transferring wheels 3 a and 3 b coupled to both sides of the driving wheel 2 such that transferring wheel 3 b rotates at opposite direction to the 3 a wheel. These driving wheels 3 a and 3 b rotate permanently as the driving motor 100 and the flexible shaft 1 do.
[0062] Pair of electromagnetic clutches 5 a and 5 b is provided for switching one of the opposite directions of rotations further to the mechanism. The body of the clutches 5 a and 5 b are fastened to the body of said module through fixtures 7 a and 7 b. The shaft of clutch 5 a is fixed to the transferring wheel 3 a and the shaft of clutch 5 b is fixed to the transferring wheel 3 b. When one of the clutches 5 a and 5 b is activated by powering-on the respective direction of rotation if propagated further to the mechanism. If none of the clutches 5 a and 5 b is activated no rotation is transferred to the mechanism and the respective module does not change its pose.
[0063] The moving part of the respective electromagnetic clutch 5 a or 5 b receives the rotation from the primary transferring wheels 3 a and 3 b. When clutch 5 a is activated, its moving part receives the rotation in one direction from transferring wheel 3 a and transfers it to shaft 8 a. When clutch 5 b is activated, its moving part receives the rotation in the opposite direction from transferring wheel 3 b and transfers it to shaft 8 b.
[0064] As the shaft parts 8 a and 8 b are fastened to the body of the next module 20 and articulates at the body's edge of module 10 , when one of the clutches 5 a or 5 b is activated, the torque is transferred to swivel the module 20 at a desired relative angle to module 10 . The same happens for each successive pair like modules 20 and 30 , etc. The encoder 9 , the body or which is fixed to the body of module 10 (or 20 , 30 , etc.) and the shaft of which is attached to shaft 8 a measures this relative angle. An electromagnetic break 6 is provided to keep this angle fixed for performing a desired pose of the robot. The body of the break 6 is fixed to the body of module 10 (or 20 , 30 , etc.) and the shaft of 6 is fastened to the shaft 8 b.
[0065] In order to achieve appropriate torques for the plurality of modules 10 , 20 , 30 , etc., and their mechanisms, the triple of wheels 3 a , 3 b and 3 c should be selected to give appropriate ratio of the bevel gear.
[0066] As the kinematical scheme and principle of operation of the second embodiment mechanism can be designed in a variety of concrete mechanical constructions, they are considered as not deviating from the spirit of the present invention and therefore embraced by it.
[0067] A third embodiment obtained by modification of the first embodiment is shown on FIG. 3 , where manipulator arm or “elephant trunk” configuration of the redundant modular robot is presented. In this case the entire scheme of the first embodiment is preserved and augmented by a base module providing two additional robot degrees of freedom, installed to appropriate working space.
[0068] One axial rotating degree of freedom is obtained by a second driving motor 200 , the body of which is fastened to a body 201 articulating around the body of the proximal robot module 10 . Pair of transferring wheels 202 and 203 is used for passing the torque of motor 200 to the body of module 10 . Wheel 202 is fixed to the output shaft of the motor 200 and wheel 203 is fixed around the body of module 10 . The speed and desired angle of rotation are achieved by appropriate control of motor 200 .
[0069] Second rotating degree of freedom about a vertical axis is obtained by a third driving motor 300 , the body of which is fastened to the body of the base 301 installed to the working space. The body 201 articulates in appropriate bearing in the body 301 . The output shaft of motor 300 is fixed to body 201 , which receives the torque produced by motor 300 directly. The speed and desired angle of rotation are achieved by appropriate control of motor 300 .
[0070] Alternatively, the base 301 can be installed on a mobile platform for performing mobile robot manipulation.
[0071] As this invention may be concretized in several forms without deviating from the spirit of indispensable characteristics thereof, the present embodiments are therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims, or equivalence of such metes and bounds thereof are therefore intended to be enfolded by the claims. | 4y
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BACKGROUND OF THE INVENTION
This invention relates to a solar heat collector designed to transfer solar energy to a liquid. Past designs of liquid heating solar colectors have been of two general types: those pressurized throughout and those which utilize gravity to create liquid flow over an absorber surface, these being commonly known as trickle, gravity-flow or open collectors, one of the most well-known of which is the subject of U.S. Pat. No. 3,360,539 by Thomason. With regard to materials, most collectors are made of either metal or plastic.
A major advantage of trickle type collectors is that they do not require the construction of pressurized spaces or the use of extensive lengths of tubing in their manufacture, but their problems include the fact that at low liquid flow rates there is poor thermal contact between the absorber and the liquid because of non-uniform liquid distribution. To prevent evaporation and cooling, the wetted surface of the absorber must be contained in an essentially vaportight enclosure. This has been accomplished by placing one or more layers of glazing over the absorber surface. The cost of this glazing is a significant part of the collector's cost. Condensation on this glazing tends to reduce light transmission through it. Sealing the glazing economically and in a vapor-tight manner has also been a problem.
Ying-Nien Yu, in U.S. Pat. No. 3,943,911, discloses the use of a thin plastic film over the absorber surface to assist in evenly spreading the liquid over the absorber. He also proposes the use of the plastic film as the absorber itself. However, many plastics deteriorate when exposed to sunlight, and when used with a rigid frame to seal their edges, they wrinkle as the result of thermal expansion and contraction, Wrinkling disturbes the even and uniform flow of liquid. Although some plastic films are stiff and do not wrinkle unless stressed in some manner, other plastic films which might be suitable for use in a collector are very soft and must be kept under tension for them to lie flat and free of wrinkles.
A major advantage in the use of plastics in solar collectors is the absence of corrosion problems. However, low-cost plastics, such as polyethylene, deteriorate when exposed to sunlight and melt at relatively low temperatures. Consequently, the use of glazing over plastic collectors is usually hazardous because a temporary loss of liquid flow might result in the plastic being heated to the melting point. Plastics which are able to withstand relatively high temperatures and exposure to sunlight tend to be expensive. Efforts to offset the loss of strength as the result of temperature or prolonged sun exposure by increasing the thickness of the plastic in a collector also tend to reduce the efficiency of the collector, as most plastics tend to be relatively poor heat conductors. No economical way has been found to solve these problems of plastic collectors. The present invention, however, offers solutions to these problems and also provides other advantages.
SUMMARY OF THE INVENTION
It is the major object of the invention to combine the simplicity and low cost of trickle type collectors with the higher efficiency of pressurized collectors.
Another object is the use of high temperature plastics, such as nylon and teflon, in thin film form, to reduce the quantity of plastic used.
Another object is to combine the advantages of plastics, especially the lack of corrosion problems, with the advantages of metals, such as strength and tolerance to sunlight.
Another object of the invention is to permit the construction of a collector consisting of a thin metal and plastic absorber combination to permit the flow of heat from the absorber surface to the plastic-contained liquid with minimum heat flow resistance.
Another object of the invention is to permit the assembly of a solar heat collector using very light materials to facilitate installation.
Another object is to permit the assembly of a collector on a flat wooden surface without the need for a frame structure around the edge of the collector.
Another object is to enable at least one exterior wall of a mobile home to act as a solar collector or radiator with minimum modification of the conventional design of such walls.
Other objects become apparent from the following disclosure.
Basically, the collector comprises a thin film tube sealed in a manner which gives it the properties which are the objects of the invention. A pipe is connected to the upper end of the thin film tube to allow the flow of liquid into the tube. The thin film tube is mounted on a vertical or inclined surface so that liquid passes through the tube by gravity to a gutter-like pipe at the lower end of the tube. Flow within the tube is restrained by a series of pockets which are formed by sealing opposite sides of the tube. In a preferred embodiment of the invention, the pockets are arranged so that the liquid passing through the tube flows from pocket to pocket. Because the liquid in each pocket makes constant static-pressure contact with the sun-facing side of each pocket, it is appropriate to consider each pocket a small pressurized flat plate collector. However, as liquid moves through the collector by gravitational force, the collector has the characteristics of trickle type devices when considered as a liquid conduit in a circulation loop. For these reasons, the invention is called a hybrid.
In a preferred embodiment of the invention, the thin plastic film tube is located between a thin metal solar absorber sheet and a rear supporting surface. The metal absorber sheet provides both physical and solar protection for the thin film tube. Expansion of the pockets in the space between the absorber and the rear supporting surface tends to press the pockets against the absorber, creating close contact for the efficient transmission of heat from the absorber to the liquid in the pockets.
There are two general methods of creating pocket structures within the film tube: the first is to seal opposite sides of the tube by means of conventional heat-sealing techniques or through the use of solvents or adhesives; the second is through the use of compliant restrictions in the tube, the detailed description of which follows.
There are three general methods by which liquid can be passed through the pockets: the first is by overflow of each pocket; the second is by means of a mechanism which releases liquid from each pocket after the liquid in it has attained a certain depth; and the third is by one or more passages in the walls of each pocket which will enable continuous flow more or less proportional to the depth of liquid in each pocket.
These various methods of pocket construction and liquid movement through the pockets may be combined. The primary advantage of passages which permit continuous flow is that they permit the pockets to drain during periods of collector non-use. The primary advantage of using pocket liquid depth as a controlling factor in liquid flow through a system of pockets is that each pocket may be filled and provide liquid contact with its sunward surface at low flow rates and at higher flow rates there is no cumulative pressure transmission through the film tube structure; the pressure in each pocket remains more or less constant regardless of flow rate. This enables the film tube structure to be made of thin plastic film.
The construction of a compliant restriction mechanism for the control of liquid depth in each pocket may take various forms. One of these is to place a film tube in a sandwich structure, at least one layer of which is composed of a stiff material, such a thin metal sheet, formed with ridges which face inwards towards the film tube. This metal sheet is is mounted in a manner which causes the ridges to pinch the film tube against a rigid surface, creating at least, and preferably, a partial seal to liquid movement. Liquid collecting behind each seal exerts pressure on the sandwich, deflecting the metal sheet outwards and releasing the seal, allowing liquid to flow to the next pocket. A variety of other methods may be used to create pinch seals. For example, strips of spring steel may be pressed against a film tube, these strips located in a manner which allows liquid pockets to form above them, these pockets developing sufficient pressure to flex the metal strips outward, releasing the pinch seal.
One of the objects of the present invention is to permit the use of used offset printing plates in the construction of solar collectors. These plates are of a suitable thickness and size for use as absorber sheets with film tubes which have heat-sealed pockets, or these aluminum sheets may be ridged to create pinch-seal structures.
Most mobile homes manufactured today have exterior siding made of ridged aluminum sheets attached to a plywood surface. In many instances, these ridges are vertical and face outward. By the use of inward-facing ridges, properly spaced for the thickness of the aluminum sheet used and the width of the film tube use, these mobile homes may have one or more of their walls used as solar heat collectors or as night-time heat radiators with the only additional expense above present construction cost being the inclusion of the film tubes in the wall structure and the addition of the appropriate plumbing to supply liquid to the film tubes and remove it from the lower edge of the wall. Liquid for the system may be stored in drums under the mobile home.
DRAWING DESCRIPTION
FIG. 1 is a perspective view of two collectors made according to the present invention shown as though made with transparent plastic to illustrate internal liquid static and flow conditions.
FIG. 2 is a perspective view of two collectors with metal absorber sheets, one shown in partial section.
FIG. 3 is a perspective view of a collector using metal sandwich construction with pockets created by pinch sealing.
FIG. 4 is a perspective view of a mobile home with exterior siding made of collectors.
DETAILED DESCRIPTION
The word "pocket" as used in this specification indicates a structure which will retain a quantity of liquid at least three times greater than would be contained in the tube during unhindered gravity flow through a film tube of the same material at the same angle. As an additional definition, any seal pattern in a film tube which causes the major part of the film tube to bulge outward above the seal pattern during liquid flow accomplishes the function of creating "pockets" in the film tube. As a further refinement of the definition, it is the property of a pocket made according to these specifications to retain liquid flow in a manner which creates a unique zone of static pressure, this static pressure not being transmitted to other pockets in a cumulative fashion. As an additional further refinement of the definition, pockets made according to this specification will cause a maximum of film tube surface to be in contact with circulating liquid under positive pressure throughout a range of flow rates without permitting cumulative pressure increase down the length of the collector. There are a variety of sealing patterns and sealing structures able to produce pockets which perform according to these specifications. The importance of pocket designs which do not allow cumulative increases in pressure down the length of a film tube nor substantial increases of pressure with increasing flow rate is that a film tube made with such pockets may be made of a thin plastic which need be no stronger than required to support the liquid depth in each separate pocket. If such a film tube is used in a sandwich with an aluminum cover plate, that plate need be no stronger than required to withstand the pressure within each pocket resulting from the depth of liquid in that pocket, Various pocket designs are illustrated by the drawings.
FIG. 1 is a perspective view of two collectors showing liquid flowing through them and a variety of pocket designs. The two thin film tubes, 1 and 2, each having a pair of opposed and generally parallel side walls joined together at their side edges, are depicted as though transparent. In actual practice, these film tubes would be made of a darkened plastic or covered with a metal cover plate. The film tubes are mounted on a rigid surface 3 by means not shown but which might include adhesives. Liquid 4 enters the thin film tubes by means of a pipe 5 which passes through the upper end of the film tubes. Holes 6 and 7 permit the passage of liquid into the film tube from the pipe 5, which is connected to a suitable source of pressure, not shown. Seals 8 and 9 at the upper end of the left-hand tube 1, are generally perpendicular to the side edges of tube 1 and extend therebetween and each seal has an opening adjacent one of the side edges so as to require liquid to flow in a zig-zag path. This simple configuration, although lacking in various refinements, does create, under ideal conditions, some of the essential phenomina related to pocket design. As seals 8 and 9 retard liquid flow and cause liquid level to rise above each seal, thereby producing an outward bulging of the film tube, for a given rate of flow this simple seal pattern could accomplish some of the objectives of the present invention. The ideal flow rate would cause each horizontal segment of the seal pattern to be mostly filled with liquid. However, minor variations in seal pattern or wrinkling of the film tube can produce significant changes in flow resistance within the film tube. This can cause one segment of a series of segments to have a higher flow resistance than prior segments. At sufficiently high rates of flow this will cause cumulative pressure increase above the high-resistance segment. This may result in sufficiently high pressure at the high-resistance point for the film tube to rupture. The safe flow rate through such a structure may be sufficiently low as to expose only a small part of the film tube's surface to static pressure. A metal plate sandwiching such a film tube against a stiff surface can transmit heat through the metal to areas of the film tube under liquid pressure. However, a thinner metal plate can be used with equal effectiveness if the film tube uses a seal pattern which increases the area of static pressure.
Seals 10 and 11 create pockets of static liquid pressure because of the downward slope of the seals. This configuration increases the area of the film tube in liquid contact regardless of flow rate and provides a minimum surface area exposed to static pressure.
Seals 12 and 13 establish a somewhat different type of flow pattern than the seals previously described. Seal 12 is generally perpendicular to the side edges of tube 1 and has an opening intermediate its ends. Seal 13 is generally parallel to the side edges of tube 1 and is connected to one end of seal 12. These seals establish a rectangular area for the liquid pocket, with a flow baffle in the center of the pocket. As shown, the major part of the liquid flow occurs through the opening in the lower part of the pockets formed by these seals. The side seals 13 of these pockets permit overflow to a passage 14 which is located adjacent one of the side edges of tube 1. Passage 14 is intended specifically to conduct liquid in excess of that needed to fill the pockets.
The use of an overflow passage provides a means for minimizing the hazard of cumulative pressure build-up in the pocket series. The structure provides what is, in effect, a pressure regulatory mechanism for the pockets in the film tube. In the design of a series of pockets such as shown in the lower half of the film tube, each pocket may be designed to present a slightly greater restriction to flow than the one above. In this manner, all of the pockets will fill completely, with any excess liquid diverted to the overflow passage. The lower three pockets 15 of the film tube each have a first portion laterally extending between side edges of tube 1 and a second portion extending at an angle between the side edges. The first portion of pocket 15 also has a number of openings through which the liquid flows longitudinally. Pockets 15 are shown with overflow passages arranged in a manner which requires liquid level in a pocket to rise slightly above the bottom of the pocket above it before overflow may occur. With this type of seal pattern, an entire film tube may be liquid-filled, with the only air in the tube being that in the overflow passage.
The arrangement of the overflow passage in left-hand film tube 1 of FIG. 1 requires that the liquid flow rate for the structure be adjusted with some care so as to be sufficient to fill all of the pockets and yet not so great as to create major flow through the overflow path. The right-hand film tube 2 of FIG. 1 illustrates pocket designs which are less sensitive to liquid flow rate in keeping the pockets full, and yet cause all of the liquid passing through the structure to pass through pockets. The uppermost pocket 16 is illustrated with two flow paths: a slow-flow path 17 on the bottom of the pocket and a larger overflow path 18 on the side of the pocket. The slow-flow path is intended to provide overnight draining of the pocket, with the majority of liquid flow occuring by means of the overflow path.
Pocket 19 of the right-hand film tube 2 uses a diverter seal 20 which deflects liquid running down the overflow path 21 into the next lower pocket 22. This seal configuration permits the upper limit of the liquid level in each pocket to be even with the bottom of the pocket above it and yet still permit a continuous overflow passage on the right hand side of the collector. One desirable feature of a continuous flow passage on one or both sides of the collector is that it permits the escape of trapped air.
Liquid is withdrawn from the collectors by means of a gutter-like pipe 23. The top of the pipe has a slot cut in it to allow the entry of the film tube. Liquid from the tubes drains into this pipe from which it then flows by gravity.
FIG. 2. illustrates two embodiments of the invention. Two film tubes 24 and 25 are shown mounted on a common base 26, using a common upper liquid supply pipe 27. The collector on the left is shown with a metal absorber sheet 28 in partial section. The sheet is attached to the supporting surface by staples 29. The expansion of the film tube 24 as its pockets fill with liquid press the film tube against the absorber sheet, enabling heat absorbed by the sheet to flow into the liquid circulating through the film tube. The seal pattern of this film tube creates pockets which are connected in parallel with respect to liquid flow. Specifically, tube 24 has pockets which include a first portion laterally extending for a portion of the distance between the side edges of tube 24. A second portion is connected to one end of the first portion and extends in an upward direction toward pipe 27. Similarly, a third portion is connected to the other end of the first portion of the pocket. This third portion also extends in an upward direction toward pipe 27. The liquid completely fills the pockets of tube 24 before flowing out of the open, upper portion of the pocket. In contrast, FIG. 1 illustrates pocket structures which are connected in series or series-parallel. Regardless of pocket connection circuit, the pressure of liquid within the film tube is transmitted almost entirely to the absorber sheet, enabling the film tube to be made of very thin plastic.
The right hand collector 25 of FIG. 2 is covered with a ridged absorber sheet 30. The pressure of the ridges of the absorber sheet against the mounting base 26 creates pinch seals which cause liquid to build up in the film tube. The pocket of liquid above each pinch seal has a static pressure which causes the absorber sheet to bow outward, releasing the pinch seal. As a means of increasing the pressure of the pinch seal, the absorber sheet or mounting base may be bowed inward towards the center of the collector prior to assembly. In the case where the base has been bowed, pinch seals also may be created by tensioning the absorber sheet by springs along the edge of the absorber sheet. The lines of tension across the absorber sheet created by these springs will pinch the plastic tube, resulting in the same effect as the ridged absorber sheet 30 of FIG. 2.
FIG. 3 illustrates the use of two ridged metal sheets to create a pinch seal for an inner film tube. The two sheets 31 and 32 are held together at their edges by tabs 33. The thin film tube 34 between the sheets is shown by dashed lines. A pipe 35 passes between the metal sheets and through the thin film tube to conduct liquid into the film tube. The bottom of the film tube is inserted in a slot cut in the top of a lower pipe 36 to conduct liquid from the collector. The two metal sheets may be formed with an inward-facing bow prior to assembly to increase the force of the pinch seal after assembly.
FIG. 4 illustrates the use of aluminum siding similar to that used by most mobile homes. Film tubes 37 are shown by dashed lines placed between the siding and plywood backing so as to convert the walls of the structure into solar energy absorbers. The siding has the form of the absorber sheet of the right hand collector of FIG. 2. A cap 38 covers the pipe used to supply liquid to the film tubes under the siding. Along the lower edge of the siding a pipe 39 removes liquid as it leaves the film tubes. The liquid is conducted to an insulated enclosure 40 below the trailer. Heated water from the collectors is stored in containers in this enclosure. Vents in the floor of the trailer allow heat from the containers to circulate up to the interior of the trailer. A heat exchanger may be used with these containers to provide domestic hot water. A pump and automatic control system are required to circulate water through the film tubes during suitable periods. During periods of warm weather, this system may be used to cool the walls of the trailer by circulating water through the tubes at night to cool it, and then circulating this cooled water through the tubes during the day to reduce wall temperature.
The configuration of the pinch seals used to form pockets need not be limited to the simple ridges shown in FIG. 2 and FIG. 3. Double or triple ridges and the use of compliant material behind each ridge as a means of improving the pinch seal are contemplated. The absorber sheet may be embossed with a pattern which will contribute to its stiffness and that of the pinch seal area, which may be further augmented by springs and stiffening elements.
To obtain temperatures from a collector which are high relative to atmospheric temperature, some type of glazing over the collector is essential. This glazing may take the form of plastic sheets bowed over the collector and attached directly to the base supporting the collector. Glazing may also be attached to or supported by a flange bent up from the edge of the absorber sheet. Heat loss through the metal of the absorber to the glazing will be slight if the absorber is made of a very thin material, as possible with the present invention.
It is also contemplated that the solar collectors of the present invention may be formed by sealing two sheets of plastic together to create two or more film tubes side by side. In creating a multiple number of film tubes in this manner, distribution passages may be formed at the upper ends of these film tubes so that liquid can be directed to more than one film tube from a single plumbing connection in the assembly. In a similar manner, a single plumbing connection may be used to remove liquid from multiple side-by-side film tubes created within two sheets of plastic, or one larger sheet folded in half and then sealed in a manner to create multiple film tubes and passages delivering liquid to them.
In these specifications the term "plastic" is used to indicate a flexible substance manufactured in sheet form. Examples of such material are nylon, teflon, mylar, lexan, polyethylene, polybutylene and various rubber-like materials such as butyl and latex. The plastic tubes may be extruded or formed by heat-sealing the edges of two sheets. The material used may be metalic-coated or metal-foil laminated. It may also use laminations of various plastics combined in a manner which emphasizes perperties unique to each of the layers of the lamination.
Because of the possibility of small leaks which may not adversely effect the solar energy collecting performance of a film tube but which may produce problems for the mounting surface under the collector by wetting it, film tubes may be used with one or more film tubes surrounding them. In this way the outer film tube acts as a conductor for leaks from the inner film tube and thereby protects the mounting surface from liquid contact.
The present invention presents a unique economic advantage to the builder in permitting the use of used offset printing plates for the absorber sheet with either overflow or pinch-seal pocket structures. These sheets are typically available in the range of from 0.008 to 0.011 inches thick. They are sufficiently strong to support the pressure created by liquid pockets approximately ten inches deep by ten inches wide. When formed with ridges to create pinch seals, they are effective for pockets approximately 10 inches wide by three inches deep. These aluminum sheets are typically available at considerably less cost than new sheets of the same size. The present invention provides a unique use for these sheets as they are too thin to tolerate the corrosion which would result from prolonged liquid contact and also too thin to be used with pressurized structures with significant internal pressures restrained by the sheets. However, the design of the present invention, through the use of a plastic film tube, protects the aluminum from liquid contact, and limits the pressure to which it is exposed to the depth of liquid in the pockets. | 4y
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation in Part of application Ser. No. 10/695,633 to Moffat, Randazzo, McCoy, and Allen, with a filing date of Oct. 27, 2003 which is herein incorporated by reference in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] This invention relates generally to coated substrates, and more specifically to substrates coated with silanes.
[0004] 2. Description of Related Art
[0005] The macroscopic properties of a surface can easily be characterized by observing the shape of liquid droplets on the material, which is a result of the free energy of the surface, as well as the free energy of the liquid. The force per unit length affecting the surface or interface is the interfacial tension γ, which is usually expressed in units of mN/m or dyn/cm. When a liquid does not completely wet a surface, it forms an angle θ, which is known as the contact angle and is measured with a goniometer. The contact angle is the angle formed between a substrate surface and the tangent line at the point of contact between a liquid droplet and the substrate surface.
[0006] The wetting ability of a liquid with respect to a solid surface can be characterized by measuring the contact angle between the liquid meniscus and the surface; a contact angle of less than 90 indicates that the substrate is readily wetted by the liquid, while an angle greater than 90 shows that the substrate will resist wetting. If the liquid wets the surface completely, the contact angle will be 0. In the opposite case, when there is not interaction between the surface and the liquid, the contact angle will be 180.
[0007] High energy substrates will be readily wettable by most liquids. In contrast, low energy substrates are only wettable by liquids whose own surface tension is low enough. Waterproofing of materials may involve the coating of the material with a relatively non-wettable material so that water breaks off instead of soaking in.
[0008] The printing industry is an example of a field where surface energies and contact angles are important considerations. It has long been recognized that the first step in obtaining good adhesion and print quality is to assure that the ink wets out on the substrate evenly. The primary forces involved are the surface tension of the ink and the surface energy of the film (substrate). In order for the liquid to sufficiently wet out on the surface of the substrate, the material has to have high enough surface energy, in relation to the surface tension of the liquid being applied. If the tension of the liquid is higher than the surface energy of the substrate, the molecules of the liquid would tend to cling together, forming a bead or drop.
[0009] Compounds are often added to either to the inks to alter their surface tension, or to the surface of the substrate to alter its surface energy, in order to deliver high quality printing. If there is too much wetting, the ink may spread out and not deliver resolute printing. On the other hand, if there is not enough wetting, the ink may bead up and run off. The paper that is used in many printing applications is viewed as having a certain surface energy. The variability in the surface energy of the paper, or surface to be printed, across the surface has an effect on the ability of the process to match the surface with an appropriately surface tensioned ink, and therefore has an effect on the resolution and the quality of the printing process.
[0010] A newer field of printing is the printing of DNA microarrays on glass slides. DNA microarrays are used in hybridization based assays including the measurement of comparative gene expression levels. The printing of DNA onto glass slides includes a process referred to as DNA immobilization. Oligonucleotides are often immobilized onto glass slides. A DNA microarray consists of different types of DNA strands printed onto different areas of the slide. The process of immobilizing DNA strands onto an area of the slide is analogous to the printing of an ink drop onto paper in the sense that surface energy of the substrate and the surface tension of the DNA laden liquid, which primarily determine the amount of wetting, effect the resolution that the process can attain. In addition to the DNA array chips now used, protein array chips may have many possible applications in the future.
[0011] A basic building block of many types of these chips is a substrate topped with an organic silane molecule monolayer. The substrate may consist of silicon or glass or other materials. Earlier processes resulted in silane layers which were inconsistent across their surface area, which was seen in variations in contact angle measurements across the surface area. Variation in the contact angle across a surface would be greater than +/−10.
[0012] Across the surface of a glass or silicon substrate are hydroxyl ions entrenched in the substrate itself. The hydrogen of the embedded hydroxyl ion extends away from the surface of the substrate. In a reactive process with silanes, such as silicon trimethyl, the Si of the silicon trimethyl group supplants the hydrogen of the embedded hydroxyl, resulting in a very strong bond to the substrate. This organic/inorganic bridge then allows for the immobilization of DNA or protein strands onto the substrate.
[0013] If the substrate has moisture on its surface, the Si of the silicon trimethyl group may instead supplant the hydrogen of a water molecule on the substrate surface. In contrast to the strong bond to the substrate achieved when the Si is attached to the oxygen atom of the hydroxyl ion, which is embedded in the substrate, there is no such strong bond when the hydrogen of the water molecule is supplanted. The silane layer formed in the presence of moisture on the substrate is therefore inconsistent, with some portions of the silane layer strongly bonded to the substrate while other portions are not. The portion of silane layer which is not strongly bonded to the substrate may not stay attached to the substrate. This loss usually occurs immediately, upon the first exposure to moisture, or during subsequent processing of the coated substrate.
[0014] A method and apparatus for forming a consistent silane layer without, or with a minimum of, moisture related defects is discussed in U.S. patent application Ser. No. 10/656,840, to Moffat and McCoy, with a filing date of Sep. 5, 2003, and is hereby incorporated by reference in its entirety.
[0015] Another use for forming a consistent silane layer with a minimum of defects is the prevention of diffusion of copper into layers such as dielectrics in fields such as semiconductor manufacturing. Silane may be used as a diffusion barrier between copper and other layers, such as dielectrics layers, during the copper deposition process, subsequent annealing processes, or other processes. The use of silane in this manner may allow the diffusion barrier layer to be significantly thinner. A consistent silane layer, even after significant exposure to moisture, allows for the creation of a thin copper diffusion barrier with less defects. Multiple silane layers, using either a single silane or different silanes, may also be used to reduce defects.
[0016] Prior silane coated substrates have had some serious drawbacks. Because the layer had numerous areas where the layer was bonded to water on the surface, the surface energy across the surface of a layer would vary, as the weakly bonded areas immediately degraded. This variation in the surface energy resulted in variations in the contact angle with a given liquid, and had a negative impact upon the consistency and resolution of DNA microarray printing. As higher densities of microarrays were sought, the inconsistency of the silane layer, because of these defects, becomes a limitation. Prior silane coated substrates have variations in contact angle measurements across their surface area of +/−10 and greater.
[0017] A second serious drawback of prior silane coated substrates is that the inconsistent silane layer adds uncertainty to the results of the assays done using the microarrays. If the silane layer is inconsistent, then the density of DNA strands per unit area of the substrate after immobilization would also be inconsistent. This condition can interfere with the accuracy of data from the assays performed.
[0018] A drawback of prior copper diffusion barrier layers used in semiconductor and other manufacturing has been the thickness of such layers. The use of silane in applications such as diffusion barrier layers allows for a thinner barrier layer, allowing for the more efficient use of space. Defects in a silane layer used a diffusion barrier might lead to faults in a semiconductor, thus a silane layer with a minimum of defects enhances is favored over other methods. In addition, the use of a vapor process to deposit silane onto a porous dielectric layer allows for penetration into pores and further limits any shortcomings in the prior art methods.
[0019] What is needed is a substrate with a consistent silane layer and a consistent surface energy across its surface. What is also called for is a substrate with a consistent silane layer that remains consistent after exposure to moisture.
SUMMARY
[0020] A silane coated substrate with a consistent surface energy across its surface. This consistent silane layer has a contact angle with a variation of less than +/−10 degrees as measured by a goniometer. The consistent silane layer also retains its consistency in moist environments. A silane layer with a minimum of defects which may be used a diffusion barrier layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a representative cross-section of a coated substrate.
[0022] FIG. 2 illustrates a hydroxyl ion and water on a substrate surface.
[0023] FIG. 3 illustrates water droplets and contact angles on a substrate surface.
[0024] FIG. 4 shows two figurative representations of hydroxylated substrates.
[0025] FIG. 5 illustrates a molecule bonded to a substrate.
[0026] FIG. 6 illustrates a substrate coated with a silane monolayer.
[0027] FIG. 7 is a top view of a coated substrate.
[0028] FIG. 8 is a side view of a droplet on a substrate surface.
[0029] FIG. 9 is a cross sectional view of a substrate utilizing a barrier layer.
[0030] FIG. 10 is a cross sectional view of a substrate utilizing a plurality of barrier layers.
DETAILED DESCRIPTION
[0031] FIG. 1 illustrates a coated substrate 100 according to some embodiments of the present invention. The substrate 102 is glass in some embodiments of the present invention. The substrate 102 may be of a variety of glass types, including soda lime glass, borosilicate glass, or pure silica. In other embodiments, substrate 102 may be silicon. Layer 101 is a silane layer. Silane layer 101 may be comprised of amino silanes, epoxy silanes, and/or mercapto silanes in some embodiments. Silane layer 101 may be 3-aminopropyltrimethoxysilane in some embodiments. Silane layer 101 may be 3-3-glycidoxypropyltrimethoxysilane in some embodiments.
[0032] FIG. 2 illustrates a hydroxyl ion 202 embedded in a substrate 201 , as would be seen in the case of a hydroxylated substrate. A water molecule 203 is seen on the surface 204 of the substrate 201 . The substrate 201 may be glass, silicon, a dielectric coated substrate, or other surface in some embodiments.
[0033] FIG. 3 depicts illustrations of droplets 302 , 303 , 304 on the surface 301 of a substrate 300 . The droplet 302 with the least amount of wetting has the largest contact angle. The contact angle of the droplet 302 is measured as the angle from the substrate surface to the tangent line 308 constructed from the exterior contact point 305 . The droplet 304 shown with the most amount of wetting has the smallest contact angle 311 , constructed by creating a tangent line 310 at the contact point 307 . Droplet 303 has a 90 degree contact angle as determined by the angle of the tangent line 309 at the contact point 306 . A surface with a consistent surface energy will have a consistent contact angle around the periphery of the droplet, as well as having a consistent contact angle for droplets at different locations on the surface.
[0034] FIG. 4 shows two separate figurative representations of a hydroxylated substrate 401 . Hydroxyl ions 402 , 403 may be represented with either method of illustration.
[0035] FIG. 5 illustrates a coated substrate 501 according to one embodiment of the present invention. The substrate 502 has had many of the hydroxyl ions 504 embedded in its surface 505 reacted with HMDS such that silicon trimethyl 503 (methyl groups not shown) has bonded to the substrate 502 . The density of reacted hydroxyl ions on the surface is consistent across the surface 505 of the substrate 502 . This density may be altered by the pressure of the reactive process and the time duration of the reactive process in some embodiments. The surface energy of the embodiment 501 of FIG. 5 remains consistent after significant exposure to moisture. The goniometer angle measured across various points on the surface of coated substrate 501 remains consistent after significant exposure to moisture. As seen in FIG. 6 , silicon trimethyl has bonded to water on the surface 604 of the substrate 601 . The product of this reaction 603 sits on top of the surface 604 of the substrate 601 and is not strongly bonded to the substrate 601 . In contrast, the silicon trimethyl 602 that has reacted with an embedded hydroxyl ion is strongly bonded to the substrate 601 .
[0036] The silane layers according to some embodiments of the present invention have consistent thickness across the surface of the substrate. The silane layer may thicken itself with more processing time as additional silane molecules adhere to silane molecules that have adhered to the substrate in a self-assembling layer.
[0037] When the chemical reactive process utilizes substrates that have not been sufficiently dehydrated, the silane layer is formed bonding to both hydroxyl ions and to water on the surface of the substrate. These prior silane layers would thus lose consistency immediately as the weakly bonded portion of the layer was lost. This inconsistency was exacerbated during further processing as the substrate was exposed to moisture and more of the poorly adhered area was lost.
[0038] A layer that has originally been formed to have a consistent density of silane across it surface will have a consistent surface energy only if the layer remains stable after processing. A stable silane layer will have a consistent surface energy as measured by a goniometer. Different process parameters result in different surface energies. The stability of the silane layer will be demonstrated both by consistent measurements at different positions on the surface and by consistent contact angles around the meniscus of a single droplet used in contact angle measurement. The consistency of the layer will remain in the presence of moisture and throughout subsequent processing.
[0039] As seen in FIG. 7 , the substrate 701 has a variety of arbitrary positions 702 , 703 , 704 , 705 , 706 , 707 , 708 , 709 across its surface. The contact angle measurements at the positions 702 , 703 , 704 , 705 , 706 , 707 , 708 , 709 are consistent with each other within +/−3 degree in some embodiments of the present invention after significant exposure to moisture.
[0040] In some embodiments of the present invention, as shown in FIG. 8 , the substrate 801 has a droplet 802 on its surface for the purpose of measuring the contact angle. The contact angle 804 measuring the angle of the tangent line 803 at the point 808 is consistent with the contact angle 806 measuring the angle of the tangent line 805 at the point 807 to with +/−3 degree in some embodiments. The contact angle 806 is consistent with other contact angles around the meniscus of drop 802 to within +/−3 degrees in some embodiments of the present invention.
[0041] In some embodiments of the present invention, as seen in FIG. 9 , substrate 901 has undergone further processing. In some embodiments substrate 901 is a silicon substrate. Dielectric layer 902 sits upon silicon substrate 901 in this embodiment. In some embodiments, dielectric layer 902 may be sitting upon other layers that have been deposited upon the substrate. Silane layer 903 is deposited upon dielectric layer 902 , and is used as a diffusion barrier layer in some embodiments. When copper portion 904 is deposited upon silane layer 903 , silane layer 903 presents a diffusion barrier between copper portion 904 and dielectric layer 902 for example in the area of the layers' adjacency 905 . When deposited according to some embodiments of this invention, silane layer 903 is relatively defect free and is an improved diffusion barrier layer. In prior art methods diffusion barrier layers were significantly thicker. For example, a tantalum layer may be used and be 200 angstroms thick. Using an example of a trench 905 that is 1000 angstroms wide to start, the prior art barrier layers would then narrow the trench by 400 angstroms, allowing only 600 angstroms width of copper despite the 1000 angstrom starting width. According to some embodiments of the present invention, the silane layer 903 may be significantly thinner. The silane layer 903 may, for example, be 5, 10, 15, 20 or more angstroms thick. When the silane layer 903 is formed using different process parameters, such as increased process time, the layer will self-assemble and become thicker. The controlled thickness of the silane layer 903 , and the use of a thin silane layer 903 , provide benefit in this and other applications.
[0042] In some embodiments of the present invention, as seen in FIG. 10 , substrate 1001 has undergone further processing. In some embodiments substrate 1001 is a silicon substrate. Dielectric layer 1002 sits upon silicon substrate 1001 in this embodiment. Silane layer 1003 is deposited upon dielectric layer 1002 . Silane layer 1104 is deposited upon silane layer 1003 . Silane layer 1003 and silane layer 1004 are the same type of silane in some embodiments. Silane layer 1003 and silane layer 1004 are different types of silane in some embodiments.
[0043] A process for the coating of substrates in a process chamber, which may include dehydrating the substrate, and vaporizing the chemical to be reacted prior to its entry into the process chamber. Among the benefits of this invention are the enhancement of the repeatability of the process product and the reduction of risks associated with processing.
[0044] A substrate for the chemical deposition of different chemicals may be of any of a variety of materials. For biotech applications, a glass substrate, or slide, is often used. Glass substrates may be borosilicate glass, soda lime glass, pure silica, or other types. In some semi-conductor applications, the substrate may be silicon with other layers including dielectrics layers already processed. Substrate dehydration may be performed as part of some processes. The substrate is inserted into the process chamber. The substrate is then dehydrated. Residual moisture interferes with the adhesion of chemicals during the deposition process. Alternatively, dehydration of the substrate allows for later rehydration in a controlled fashion. The dehydration process alternates exposing the substrate to vacuum and then to heated nitrogen, either once or multiple times. For example, the substrate would be exposed to a vacuum of 10 Torr for 2 minutes. At this pressure water boils at about 11 C. The vacuum chamber would then be flooded with preheated nitrogen at 150 C. This part of the process would heat the surface of the substrate so that the high temperature of the slide would assist in the dehydration process as vacuum was once again applied. After 3 complete cycles, a vacuum of 1 Torr would be applied to complete the dehydration process.
[0045] After the completion of the dehydration cycle, the substrate is ready for chemical reaction. Chemical reservoirs, such as manufacturer's source bottles, provide the chemical for the deposition process. For many processes, silanes are used. Among the silanes used are amino silanes, epoxy silanes, and mercapto silanes. Chemical may be withdrawn directly from the reservoir. A metered amount of chemical is withdrawn from the chemical reservoir. This may be done by opening a valve between the chemical reservoir and a withdrawal mechanism. The withdrawal mechanism may be a syringe pump. Chemical is withdrawn from the reservoir, enters the syringe pump, and then the valve between the chemical reservoir and the syringe pump is closed. The chemical reservoirs may be purged with an inert gas such as nitrogen. This purging allows for the filling of the volume of fluid removed with an inert gas, minimizing contact between the chemical in the reservoir and any air or moisture.
[0046] Next, a valve between the syringe pump and a vaporization chamber is opened. The vapor chamber may be pre-heated. The vapor chamber may be at reduced pressure. The syringe pump then pumps the previously withdrawn chemical from the syringe pump to the vaporization chamber. The vapor chamber may be at the same vacuum level as the process oven. In parallel to this delivery of chemical to the vaporization chamber, a second chemical may be undergoing the same delivery process. The two chemicals may vaporize at substantially the same time. Additionally, more chemicals may also be delivered to the vaporization chamber, or to another vaporization chamber.
[0047] The reduced pressure in the vapor chamber, and/or the elevated temperature in the vapor chamber may allow for the vaporization of chemicals at pre-determined pressure levels and temperatures.
[0048] The vaporized chemical, or chemicals, are then delivered to the process chamber. This may be done by opening a valve between the vaporization chamber and the process oven after the chemical has vaporized in the vaporization chamber. Alternatively, the valve between the vaporization chamber and the process oven may already be open when the chemical, or chemicals, are delivered to the vaporization chamber. The chemical then proceeds into the process chamber and reacts with the substrate.
[0049] In one example, a process for the creation of a layer of 3-Glycidoxypropyl-trimethoxysilane on a substrate of glass. The above mentioned silane is provided in a 98% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 5 ml of this silane is provided to a vapor chamber which has been pre-heated to 150 C. and has a pressure of approximately 5 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 2 minutes in this example.
[0050] In another example, a process for the creation of a layer of 3-Glycidoxypropyl-trimethoxysilane on a substrate of glass. The above mentioned silane is provided in a 98% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 10 ml of this silane is provided to a vapor chamber which has been pre-heated to 190 C. and has a pressure of approximately 10 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 2 minutes in this example.
[0051] In another example, a process for the creation of a layer of 3-Glycidoxypropyl-trimethoxysilane on a substrate of glass. The above mentioned silane is provided in a 98% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 10 ml of this silane is provided to a vapor chamber which has been pre-heated to 190 C. and has a pressure of approximately 16 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 10 minutes in this example.
[0052] In another example, a process for the creation of a layer of 3-aminopropyltrimethoxysilane on a substrate of glass. The above mentioned silane is provided in a 97% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 2 ml of this silane is provided to a vapor chamber which has been pre-heated to 100 C. and has a pressure of approximately 3.5 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 20 minutes in this example.
[0053] In another example, a process for the creation of a layer of 3-aminopropyltrimethoxysilane on a substrate of glass. The above mentioned silane is provided in a 97% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 5 ml of this silane is provided to a vapor chamber which has been pre-heated to 90 C. and has a pressure of approximately 6.5 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 20 minutes in this example.
[0054] In another example, a process for the creation of a layer of 3-aminopropyltrimethoxysilane on a substrate of glass. The above mentioned silane is provided in a 97% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 10 ml of this silane is provided to a vapor chamber which has been pre-heated to 150 C. and has a pressure of approximately 16 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 20 minutes in this example.
[0055] In another example, a process for the creation of a layer of 3-aminopropyltriethoxysilane on a substrate of glass. The above mentioned silane is provided in a 99% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 5 ml of this silane is provided to a vapor chamber which has been pre-heated to 90 C. and has a pressure of approximately 2.75 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 20 minutes in this example.
[0056] In another example, a process for the creation of a layer of 3-aminopropyltriethoxysilane on a substrate of glass. The above mentioned silane is provided in a 99% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 10 ml of this silane is provided to a vapor chamber which has been pre-heated to 150 C. and has a pressure of approximately 11.5 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 10 minutes in this example.
[0057] In another example, a process for the creation of a layer of 3-aminopropyltriethoxysilane on a substrate of glass. The above mentioned silane is provided in a 99% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 10 ml of this silane is provided to a vapor chamber which has been pre-heated to 150 C. and has a pressure of approximately 9 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 5 minutes in this example.
[0058] In another example, a process for the creation of a layer of 3-aminopropyltriethoxysilane on a substrate of glass. The above mentioned silane is provided in a 99% solution. After dehydration of the slide, the silane is routed to the vapor chamber. In this example, 10 ml of this silane is provided to a vapor chamber which has been pre-heated to 150 C. and has a pressure of approximately 9 Torr. The valve between the vapor chamber and the process oven is open during this example of the process. The process duration after the injection of the silane into the vapor chamber is 2 minutes in this example.
[0059] Silanes which may be used in processes according to embodiments of this invention include 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, decyltriethoxysilane, 4-triethoxysilylbutyronitile, 3-triethoxysilylpropylmetacralate, triethoxysilylbutyraldehyde, 10-undecenyltrichlorosilane, dodecyltrichlorosilane, isocyanatopropyltriethoxysilane, and other chemicals. Silanes which may be used in processes according to embodiments of this invention include mercapto, epoxy, and amino silanes.
[0060] As evident from the above description, a wide variety of embodiments may be configured from the description given herein and additional advantages and modifications will readily occur to those skilled in the art. The invention in its broader aspects is, therefore, not limited to the specific details and illustrative examples shown and described. Accordingly, departures from such details may be made without departing from the spirit or scope of the applicant's general invention. | 4y
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CROSS REFERENCES TO RELATED APPLICATIONS
This is a division, of application Ser. No. 641,371 filed Dec. 17, 1975, now U.S. Pat. No. 4,044,914.
This application is related to the following commonly assigned applications which are copending herewith:
"Method and Apparatus for Transferring Refuse", by Harvey W. Lieberman and John C. Salyers, Ser. No. 641,757, filed Dec. 17, 1975; Apparatus for Loading Refuse Into Containers by Harvey W. Lieberman, Paul L. Goranson, R. Houston Ratledge, Jr. and John C. Salyers, Ser. No. 641,375, filed Dec. 17, 1975; "Method and Apparatus for Unloading Refuse Containers" by Harvey W. Lieberman, Samuel E. Harvey, J. Stephen Whitehead, and Paul L. Goranson, Ser. No. 641,524 filed Dec. 17, 1975; and "Methods Apparatus for Controlling an Hydraulic Cylinder", by Harvey W. Lieberman and J. Stephen whitehead, Ser. No. 641,370, filed
Each of the above-identified applications is expressly incorporated herein by this reference thereto.
BACKGROUND OF THE INVENTION
This invention relates generally to metallic receptacles. More specifically, this invention relates to refuse containers adapted to receive, store and transport solid waste refuse material.
Metallic containers adapted to facilitate the disposal of solid waste refuse materials have long been known in the art. Typically, however, such containers comprise a rigid structure defining an enclosed volume and having a gate or door through which solid material passes to the enclosed volume.
Often, a packing device is used in conjunction with a relatively large capacity container to compact refuse materials in the container and improve disposal efficiency. For one reason or another, refuse material may create an internal obstruction in a rigid wall container which resists the introduction of additional waste material. With rigid walls, visual determination of the existence of such a blockage is not possible. If the packer cannot overpower the obstruction it will prevent further filling of the container. Consequently, the container may be removed from the packer prematurely.
Containers are also known which have one closed end adapted to be opened for container discharge and one open end which is closed by a slidably disposed bulkhead. The bulkhead may be translated towards the closed end to effect discharge of the container contents. During filling, the movable bulkhead is positioned at the open end and the container defines an essentially constant internal volume. Refuse material typically enters the container through hatches disposed along a top container surface adjacent to the open end. See for example U.S. Pat. No. 3,720,328 issued to H.B. MacKenzie on Mar. 13, 1973.
There are several problems with respect to the known containers having a movable bulkhead. For example, a top loaded container can have substantial nonuniformity in the degree of compaction of refuse material therein. In addition, a hinged door at the closed end allows an uncontrolled rate of discharge of the material contents when the door is opened. Moreover, a hinged door can become inadvertently unlatched resulting in an undesired discharge of the container contents.
Furthermore, the known containers with movable bulkheads are not compatible with horizontally reciprocable stationary compactors. This incompatability is particularly disadvantageous in large capacity containers since capital expenditures can be substantially reduced where a single compactor can be used to fill a plurality of containers one at a time.
Another disadvantage of the known containers having a slidable bulkhead and open hatches along an adjacent top surface concerns the structure of the container. The bottom, lateral sides and occasional cross members on the top resist most of the internal forces caused by compressed refuse material thus necessitating a substantially heavier construction than is needed, for example, in a container having essentially tubular configuration.
Accordingly, it is such that a need continues to exist for a refuse container which is free from the disadvantages discussed above and which has a large volumetric capacity to advantageously employ the economy of large scale in storage and transportation of solid waste materials.
OBJECTS AND SUMMARY OF THE INVENTION
It is therefore a general object of the present invention to provide a novel refuse container free from the disadvantages of previously known containers.
It is another object of the present invention to provide a refuse container having a hingedly mounted tailgate with a latching mechanism that will not release inadvertently.
The above objects, as well as many others, are accomplished by an elongated metallic container having a cylindrical side wall with a generally rectangular cross section, a hingedly mounted end closure member, an open end, and a longitudinally slidable bulkhead assembly.
To connect the end closure member to the container frame, the end closure member is provided with a plurality of connector members which extend therefrom and which are adapted for engagement by a corresponding plurality of cam members carried by a latching assembly of the container frame. The latching assembly preferably includes an actuating assembly which moves the cam members into engagement with the connector members and retains the engagement therebetween with an over-center mechanical lock. Inadvertent release of the latching assembly is curtailed by locating the actuator assembly beneath the container.
In order to close the open end of the container, a longitudinal slidable, transversely extending bulkhead assembly is provided within the container. The bulkhead assembly is guided longitudinally and includes a releasable friction means that engages the container guides during movement of the bulkhead away from the closure member when the container is being filled with solid waste materials by a compactor. Preferably the friction means is releasable during translation of the transverse bulkhead toward the closure member to substantially reduce the force necessary to expel container contents through the opened end closure member.
The friction means may be provided with adjustments to vary the predetermined internal pressure that causes the bulkhead assembly to recede toward the open end. In this manner, the density of refuse in the container may be roughly controlled.
Longitudinally extending guide members may also be provided in the container to guide the reciprocatory movement of the bulkhead assembly between the ends of the container. As a result, the bulkhead assembly can be supported above the container floor to limit frictional contact therewith and the concomitant resistance to movement during container discharge.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention is illustrated in the accompanying drawings wherein:
FIG. 1 is a side elevation of a refuse container with alternate positions of the tailgate assembly illustrated in phantom lines;
FIG. 2 is a view in partial cross section taken along the line 2--2 of FIG. 1;
FIG. 3 is a view in partial cross section taken along the line 3--3 of FIG. 2;
FIG. 4 is an end elevational view of the tailgate end of the container of FIG. 1;
FIG. 5 is a view in partial cross section taken along the line 5--5 of FIG. 4;
FIG. 6 is a view in partial cross section taken along the line 6--6 of FIG. 4;
FIG. 7 is a partial bottom view of the container of FIG. 1;
FIG. 8 is a view in partial cross section taken along line 8--8 of FIG. 7;
FIG. 9 is a view in partial cross section taken along the line 9--9 of FIG. 1 illustrating the bulkhead resistance apparatus;
FIG. 10 is a view in partial cross section taken along the line 10--10 of FIG. 9; and
FIG. 11 is a view similar to FIG. 10 illustrating release of the resistance apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Disclosed in FIG. 1 is a container 20 according to the present invention which is adapted to receive, store and transport essentially solid waste material from a collecting location to a discharging location. One particularly desirable use for containers of the present invention is the storage and transportation of solid waste materials by rail or truck from satellite collection points to a centralized power generating facility which uses solid refuse material as a fuel.
A rectangular configuration of the container is desirable since it facilitates vertical storage of containers one on the other. While other cross sectional configurations may be selected without departing from the scope of the invention, the rectangular configuration provides good longitudinal and lateral stability against tipping.
Each container 20 includes a substantially horizontal bottom frame assembly 22 having a pair of vertically upstanding generally rectangular side walls 24 and a generally horizontal top wall 26. The bottom frame assembly 22 and side walls 24 and the top 26 define a tubular structure which is cylindrical with a generally rectangular cross section (see FIG. 2).
The side walls 24 and the top 26 may be provided with suitable reinforcing members such as the generally U-shaped steel channels 28 illustrated in FIG. 1. The walls 24, the top 26 and the bottom wall or floor 30 (see FIG. 2) may comprise sheets of suitable material such as steel which are connected at adjacent edges to provide an essentially fluid tight tubular shell.
One end 32 (see FIG. 1) of the container 20 is provided with an openable end closure or tailgate assembly 34. The tailgate 34 (see FIG. 2) is preferably hingedly connected to end columns 36 of the side walls 24 by suitable pivot pins 38 for movement about a horizontal axis 40 spaced slightly above the top surface 26 of the container 20. The upper portion of the tailgate 34 is provided with a vertically slidable closure door 42 which may comprise approximately two-thirds of the tailgate assembly 34. The lower one-third of the tailgate assembly 34 or the edge portion thereof is not adapted for movement with respect to the tailgate assembly 34 itself.
The closure door 42 includes a substantially rectangular panel 44 which faces the interior of the container to provide a relatively smooth surface. The exterior side of the closure door 42 includes vertical and horizontal reinforcing channel members 46 (see FIG. 4) of a suitable material such as steel which serve to stiffen the closure door 42 against internal pressure.
Along each vertical edge of the panel 44 is a U-shaped channel member 48 (see FIG. 5) that is suitably secured to the panel 44. The tailgate assembly 34 (see FIG. 4) includes a vertically upstanding column 50 on each side which has a tongue 52 projecting from the upper end thereof. Each tongue 52 is mounted on a corresponding pivot pin 38. Each column 50 also includes a guide bar 54 (see FIG. 5) fastened thereto and projecting toward a corresponding channel member 48 of the closure door 42. The channel members 48 and the guide bars 54 guide the movement of the closure door 42 with respect to the tailgate assembly 34. The closure door 42 is raised to the position depicted by phantom lines in FIG. 1 when the container 20 is being filled. It will be apparent to those skilled in the art that the location of the channel members 48 and the cooperating guide bars 54 may be reversed, if desired.
The lower portion of the tailgate assembly 34 (see FIG. 2) has a relatively smooth internal surface 56 defined between the columns 50, an upper cross member 58 and a lower cross member 60. The upper cross member 58 has a triangularly shaped channel 62 (see FIG. 3) mounted thereon such that an inclined surface supports the lower edge of the closure door 42.
The lower cross member 60 has an inclined surface 64 which slopes upwardly and inwardly toward the container interior. The surface 64 is spaced from the container floor 30 so that a bulkhead assembly can advance to the edge 66 during discharge of the container contents without interfering with subsequent closing of the tailgate assembly 34.
On the exterior (see FIG. 4) of the tailgate assembly 34, the lower portion is provided with a pair of spaced apart vertical members 68 which extend between the upper cross member 58 and lower cross member 60. Intermediate the ends of the vertical members 68 is a generally circular bail 70 which is positioned adjacent to the external face of the tailgate assembly 34 (see FIG. 6). The bail is also strengthened by a pair of generally horizontal plates 72 which, along with the bail 70 and the surface 56, define a space 74. The space 74 is adapted to receive a hook to lift the tailgate assembly 34 during discharge of the container contents.
The exterior of the tailgate assembly 34 (FIG. 4) is provided with a pair of laterally spaced plates 76 which are suitably connected to the structural members and which extend laterally beyond the corresponding columns 50. The extended edge portions 78 along with extended portions of the lower cross member 60 overlie the end of the side walls 24 to limit movement of the tailgate assembly 34 into the container as well as to provide a seal to inhibit liquid refuse from draining out of the container. The lower edge portion of the tailgate assembly 34 (see FIG. 7) is provided with a tailgate connecting assembly which comprises a plurality of spaced-apart hooks of latch members 80. The latch members 80 are spaced symmetrically about the center line 82 of the tailgate assembly 34; each latch member 80 includes a laterally projecting portion 84 which is directed toward the centerline 82. Each latch member 80 is essentially L-shaped and is proided with a cam surface 86 on the laterally extending portion 84.
The tailgate connecting assembly is adapted to cooperate with a second connecting assembly carried by the substantially planar bottom frame 22 of the container 20. The second connecting assembly includes a plurality of lugs or connector member 88 each of which includes a laterally extending projection 90. The laterally extending projections 90 of the connector members 88 are directed away from the centerline 92 of the frame assembly 22 and have a complementary cam surface 94 that engages the cam surface 86 of the corresponding projection 84 of the first connector assembly to the tailgate tightly against the container side walls and the container frame.
Preferably four of the first connector members 80 and four of the second connector members 88 are provided to make an effective although not unduly expensive latching assembly.
The frame assembly 22 includes a downwardly extending skirt or apron 96 (see FIG. 8) at the end of the container and underlying an edge of the floor 30. The skirt 96 is essentially flush with the container floor 30 and is free of external projections. In this manner, refuse material is unimpeded during container dumping and does not hang up. The skirt 96 is provided with a plurality of rectangular openings 98 each of which is positioned and sized to receive a corresponding latching member 84.
Positioned below the floor 30 and on the internal surface of the skirt 96 are a plurality of sleeves 100 which may comprise three plates welded together in a U-shaped configuration and welded to the skirt 96. The sleeves 100 define guides for each of the second connector members 88.
Each of the second connector members 88 is provided with a longitudinally extending ear 102 to which an adjustable tie bar 104 is pivotally connected. The second end of each adjustable tie bar 104 is pivotally connected to a corresponding lateral projection 106 extending in the longitudinal direction from a transversely slidable link rod 108.
Two transversely slidable link rods 108 are provided which are coaxially positioned with respect to one another transversely of the container 20. The link rods 108 are also axially spaced apart symmetrically about the longitudinal center line 92 of the container 20. Each link rod 108 is slidably mounted in a corresponding pair of collars 110 mounted on the frame assembly 22 such that movement of the link rods 108 toward the center line 92 of the container 20 unlatches the second connector members 88 from the first connector members 80. Movement of the link rods 108 away from the center line 92 corresponds to a latching movement of the second connector members 88 with respect to the first connector members 80.
Each of the link rods 108 along with its associated adjustable tie bars 104 provides a linkage assembly for operating the corresponding second connector members 88. Each link rod 108 is provided with a laterally extending projection 112 extending away from the tailgate assembly 34 to avoid interference with the movement of the tie bars 104 and the second connector elements 88. The lateral projection 112 may be pivotally connected to a corresponding suitably adjustable tie rod 114 which comprises a member of an over-center mechanism.
The second end of each adjustable tie rod 114 may be pivotally connected to an end portion 116 of a longitudinally slidable actuator assembly which is disposed along the center line 92 of the frame assembly 22 and between the two spaced-apart linkage assemblies.
The actuating assembly includes an actuator rod 118 that is slidably mounted with respect to the container frame assembly 22 by a pair of collars 120 mounted on transverse reinforcing channels 122 under the floor 30. The end 116 of the actuator rod 118 may include a coupling member 124 to which each of the adjustable tie rods 114 of the over-center assembly are pivotally secured.
As the actuator rod 118 moves longitudinally toward the tailgate assembly 34, the tie rods 114 of the over-center assembly cause the link rods 108 of each corresponding linkage assembly to move away from the center line 92 of the frame assembly 22. In so doing, each tie bar 104 affixed to each of the linkage assemblies causes the corresponding second connector member 88 to move away from the center line 92 into engagement with the corresponding first latch member 80.
Engagement of the first and second latching members 80,88 occurs before the tie rods 114 of the over-center assembly attain a perpendicular relationship with respect to the longitudinal axis 92 and the actuator rod 118. The actuator rod 118 is then further advanced to a second position. As the actuator rod 118 advances to its second position, the tie rods 114 of the over-center mechanism pass through a perpendicular relationship with respect to the actuator rod 118. During disengagement, the second members 88 of the latching system must first advance toward the corresponding first member 80 as the tie rods 114 pass through the perpendicular relationship with the rod 118.
The length of the adjustable tie rods 114 in the over-center mechanism must be selected so that, as the actuator rod 118 moves from the second position to the first position, the lateral projection 90 of each second connector member 80 is withdrawn laterally toward the center line 92 of the frame assembly 22 by a distance that provides clearance between the lateral projection 90 of the second member 80 and the lateral projection 84 of the corresponding first member 80.
To inhibit the unintentional and accidental movement of the actuator rod 118 toward the first or unlatched position, the actuator rod 118 is positioned on the bottom of the container where it is relatively inaccessible. To further prevent unlatching movement of the actuator rod 118, a suitable detent assembly may be provided. The detent assembly preferably includes a pivotally mounted yoke 126 (see FIG. 8) carried by the container frame assembly 22. The yoke 126 includes a lever end portion 128 and a yoke end 130 having a pair of upwardly projecting finger members 132.
The finger members 132 are spaced apart laterally to straddle the actuator rod 118 and are located adjacent to the coupling member 124 of the actuator rod 118 when the actuator rod 118 is in the second or lacthed position. Accordingly, any movement of the actuator rod 118 toward the first or unlatched position causes the coupling member 124 to abuttingly engage the finger members 132 straddling the actuator rod 118 and the finger members 132 thereby inhibit further longitudinal movement of the actuator rod 118 itself.
To insure that the finger members 132 of the pivotally mounted yoke 126 ordinarily engage the actuator rod 118 in straddling relation, the yoke member 126 is provided with a tension spring 134. The spring 134 is connected to the yoke end 130 and to the container frame assembly 22. To release the pivotally mounted yoke 126, a suitably positioned member 136 must engage the lever end 128 of the detent assembly and overcome the bias of the tension spring 134. The member 136 may be part of a container unloading system and allows the finger members 132 to rotate downwardly about the pivot 138 into a non-interfering position as illustrated by the phantom lines of FIG. 8.
Each corner of the container frame assembly 22 has a latch block 140 (see FIG. 7) that includes an elongated recess 142 which is adapted to receive a corresponding configured container lock (not shown). When the container 20 is positioned, for example, on a railroad car, the locks are received vertically by the corresponding recesses 142 of the latch blocks 140. When the container is fully seated on the railroad car to which it is to be secured, the locks are rotated 90° such that the major axis of the lock moves into general alignment with the minor axis of the recess 142.
The second end 150 (see FIG. 1) of the container 20 is open. To provide an enclosed volume for receiving refuse material in the container, the container has a longitudinally slidable refuse restraining assembly that prevents discharge of refuse material from the open end 150. The refuse restraining assembly includes a transverse bulkhead assembly 160 that can slide between the ends of the container 20.
The container walls 24 (see FIG. 9) are each provided on their inner surface with a guide assembly 162. The guide assembly 162 may comprise, for example, a U-shaped channel member 164 which is mounted on the corresponding side wall 24 so that it extends longitudinally along the container cavity. Each channel member 164 is spaced above the horizontal floor 30 and may be provided with beveled support members 166, 168. The beveled support members 166, 168, are connected to the wall 24 and engage the U-shaped channel 164 adjacent the open end thereof such that a longitudinal slot is provided along the side wall 24 on the inside of the container 20. The beveled support members 166, 168, help to avoid unnecessary corners in which refuse material may become lodged. The two guide assemblies 162 are symmetrically disposed with respect to the longitudinal centerline of the container 20.
The bulkhead assembly 160 includes a frame assembly 170 (see FIG. 10) having a vertically extending portion 172 and a horizontally extending portion 174. The horizontally extending portion 174 is provided with a pair of flanges 176. Each flange 176 extends toward a corresponding side wall 24 and has a pair of spaced apart shoes 178, 180 on the under side. The shoes 178, 180 slide on a horizontal surface of a corresponding channel 164 and guide the bulkhead assembly 160 during longitudinal translation in the container.
Each flange 176 also has a second pair of shoes 179,181 positioned on the upper side thereof in general vertical alignment with the lower shoes 178,180. The upper shoes 179, 181 perferably have a small clearance with the upper horizontal surface of the guide member 164. The upper shoes 179,181 provide stability from tipping of the frame assembly 160 about a horizontal axis extending between the side walls 24.
The vertically upstanding frame portion 172 includes a generally vertical bulkhead portion 182 at the upper end thereof which faces the tailgate assembly 34. Below the generally vertical bulkhead portion 182 is an inclined bulkhead portion 184 having its upper edge connected to the lower edge of the vertical bulkhead portion 182. The inclined bulkhead portion 184 is partially supported by the horizontal frame portion 174 and has a lower edge 186. The lower edge 186 is positioned closer to the container tailgate assembly 34 than the upper edge.
The bulkhead assembly 160 also includes a transversely extending beam 188 (FIG. 9) which is part of a vertically displaceable frame assembly. Attached to each end of the beam 188 is an L-shaped angle section 190 which is generally perpendicular to the axis of the beam 188. Each angle section 190 has a projecting finger-like flange 192 which is positioned to be received in the corresponding U-shaped channel 164. Each flange 192 has a pad 194 of suitable friction material on the upper surface thereof.
To prevent the beam 188 from moving laterally with respect to the bulkhead assembly 160, the horizontal frame portion 174 is provided, on each side, with a pair of short vertical guides 196, 198 (FIG. 10). The vertical guides 196, 198 are spaced apart in the longitudinal direction to accommodate the beam 188 and guide vertical movement thereof.
The friction pads 194 move along with the beam 188 and are positioned between the shoes 179, 181. When the beam 188 is raised, the friction pads 194 frictionally contact the upper internal surface of the U-shaped guides 164. At the same time, the lower pads 178, 180 frictionally contact the lower internal surface of the guides 164. Accordingly, the pads 194, 178, 180 cooperate to resist movement of the bulkhead assembly 160 relative to the guides 164 and thus container 20. With the beam 188 raised, the pads 178, 180, 194 inhibit movement of the bulkhead assembly 160 in either longitudinal direction in the container.
On the other hand, if the friction pads 194 are not raised vertically into engagement with the corresponding guide channel surfaces, the friction pads 194 do not engage and do not cause the lower pads 178, 180 to frictionally inhibit movement of the bulkhead assembly.
Spaced inwardly from each end and on the underside of the transverse beam 188 is a bearing pad 200. Each bearing pad 200 is engaged by a corresponding cam 202 on the end of a corresponding lever cam 204. Each lever cam 204 is pivotally attached to the horizontal frame portion 174 and has a tie rod 206 pivotally connected to its distal end. Each tie rod 206 is connected to and in general alignment with a spring actuated rod 208 that slidably extends from a corresponding end of a circularly cylindrical spring housing 210.
The spring housing 210 (FIG. 10) may be suitably attached to the horizontal frame portion 174 such as by a bracket 212. The spring housing 210 contains a compression spring 214 (FIG. 9) that resiliently urges each actuated rod 208 outwardly from the spring housing 210.
Each end of the spring housing 210 may be provided with one or more suitable adjustment bolts 216 to control the resilient force exerted on the end of the actuator rods 208. It will be seen that the force exerted on the distal end of each lever cam 204 tends to rotate the lever cam 204 causing the cam end 202 to act on the corresponding bearing pad 200. The cam end 202 thus causes the transverse beam 188 to be raised and the friction pads 194 and the lower pads 178, 180 to engage the channels 164. In this manner the bulkhead assembly 160 is frictionally restrained.
During advancement of the bulkhead assembly 160 toward the tailgate assembly 34 to discharge the container contents, it is desirable to release the friction pads 194 from engagement with the guides 164. Accordingly, the distal end of each lever cam 204 is connected to a second tie rod 218. Each tie rod 218 is pivotally connected to the lower end of an actuator rod 220.
The actuator rod 220 is positioned along a vertical plane of symmetry for the bulkhead assembly 160 and is slidably mounted in a guide block 222 (FIG. 9) positioned centrally on the beam 188. The actuator rod 220 is pivotally connected at its upper end to one arm of a bell crank 224 (FIG. 10). A second arm of the bell crank 224 is proximally disposed to a transversely extending push bar 226 carried by the vertical frame portion 172. The bell crank 224 is pivotally mounted to the vertical frame portion 172 with the second arm 225 in a generally vertical posture.
When the bulkhead is to be advanced it must be pushed. Accordingly, a suitable push rod 228 (FIG. 11) is provided with a U-shaped recess 230 which conforms to the external contour of the transversely extending push bar 226. The end of the push rod 228 also engages the second arm 225 of the bell crank 224 when it engages the push bar 226 to forcibly advance the bulkhead assembly 160. Engagement of the bell crank 224 by the push rod 228 rotates the bell crank 224 about its pivot and lifts the actuator rod 220. The actuator rod 220 acts through the tie rods 218 to pull the lever cams 204 inwardly toward the center line against the spring bias of the spring 214. Rotation of the lever cams 204 and the cams 202 permits the transverse beam 188 to lower thereby releasing frictional engagement between the friction pads 194 and the longitudinal guides 164.
When the bulkhead assembly 160 has advanced to the tailgate assembly 34 of the container 20 withdrawal of the push rod 228 releases pressure on the second arm 225 of the bell crank 224 thereby allowing the compression spring 214 to cause engagement of the friction pads 174 with the guides 164.
In operation, the closure door 42 (FIG. 4) in the upper portion of the tailgate assembly 34 is lifted so that an opening is defined in the tailgate assembly 34. The opening may be aligned with a packer assembly. Hooks carried by the packer assembly may rest on bearing strips 232 mounted on the end columns 36 (FIG. 2) so that the packer and container do not separate during loading. The packer assembly pushes refuse into the container interior under pressure.
As the refuse fills the container 20, the inclined lower portion 184 (FIG. 1) of the transverse bulkhead assembly 160 causes the refuse to fill the container vertically. Continued addition of solid waste material to the container 20 through the opened closure door 42 causes an increased pressure to be exerted against the bulkhead assembly 160. When the pressure exceeds the predetermined level, the bulkhead assembly recedes toward the open end 150 by virtue of the sliding which is allowed between the friction pads 174 and the longitudinal guides 164. When the container 20 has been completely filled, the closure door 42 is closed thereby providing a completely enclosed cargo of solid waste refuse material.
When it is desired to empty the container 20, the pivotally mounted yoke 126 (FIG. 8) of the latching assembly is displaced such that the fingers 132 no longer prevent longitudinal movement of the actuator rod 118. The free end 234 of the actuator rod 118 is engaged by suitable actuating mechanism 236 which displaces the rod 118 longitudinally along the center line of the frame assembly 22. In so doing, the second connector members 88 (FIG. 7) are withdrawn from their overlapping latching position with respect to the corresponding first connector elements 80. Accordingly, the tailgate assembly 34 is free and can be moved vertically about a horizontal axis 40 with a swinging motion.
Preferably, a push rod 228 comprising the end of a hydraulic cylinder (FIG. 11) is advanced against the push rod 226 of the bulkhead assembly 160 to engage the second arm 225 thereby releasing the friction pas 174 and beginning advancement of the bulkhead assembly 160 towards the opened tailgate assembly 34. As the bulkhead assembly 160 advances longitudinally from the second end 150 to the first end 32 of the container 20, refuse material in front of the bulkhead assembly 160 is ejected from the opened first end 32 of the container 20.
When the container is operatively connected to the associated compactor it is necessary to provide hooks engaging the end portion of the side walls adjacent to the tailgate assembly. Accordingly, the vertically upstanding end columns adjacent the tailgate assembly are provided with a reinforced surface and the side walls of the container are provided with locally reinforced structure. In this manner the damage to the container through repeated use of hydraulically operated latching assemblies is dimished.
Leakage of liquid refuse from the first end 32 of the container 20 is inhibited by a seal effect between the tailgate assembly 34 and the container side walls 24 and floor 30 when the connecting elements 80,88 are engaged.
It should now be apparent that there has been provided in accordance with the present invention a novel refuse container which substantially accomplishes the objects set forth above as well as others. It will also be apparent that many modifications, variations, substitutions and equivalents of various elements of the refuse container described above may be made without departing from the spirit of the invention. Accordingly, it is expressly intended that all such modifications, variations, substitutions and equivalents falling within the spirit and scope of the invention as defined in the appended claims be embraced thereby. | 4y
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GOVERNMENT FUNDING
The invention described herein was made in whole or in part with government support under a contract issued by the Defense Advanced Research Projects Agency (DARPA) in response to DARPA solicitation #BAA96-29 and under contract number DAA20L-94-C-3425 with the Advanced Research Projects Agency (ARPA). The United States Government may have certain rights in the invention.
BACKGROUND OF THE INVENTION
Optical resin materials which are characterized by a distributed refractive index have demonstrated usefulness in the construction of optical conductors such as, optical fibers, optical waveguides, and optical integrated circuits as well as the corresponding preforms of these conductors. In general, plastic optical fibers (POF) are considered an attractive alternative to copper cable and glass optical fibers. Typically, the plastic optical fiber (or thin, flexible rod) has a core within which light travels and a sheathing layer which surrounds the core, confines the light to the core and possesses an index of refraction less than that of the core.
The refractive index distribution of plastic optical fibers can be classified as either gradient index or step index. However, graded index plastic optical fibers (GI POF) are preferred over step index fibers for data communication applications. That is, the index of refraction, in a graded index plastic optical fiber, generally decreases radially from the core center outward until it matches the sheathing index at the core-sheathing interface. Therefore, light rays entering the core at a small angle, with respect to the axis, follow undulating paths, which is not the case for a step index type fiber. The speed of the light rays along the undulating paths increases in the regions of lower refractive index so that the travel time along these paths is nearly equal to that along the straight axial path. This results in, for example, a wider bandwidth of transmission with minimal modal dispersion and a more rapid information flow than that obtained with step index plastic optical fibers.
In general, methods of fabricating graded index plastic optical materials comprise preparation of a polymeric sheathing and a polymeric core disposed within the sheathing. The refractive index of the core and sheathing are different in that the refractive index of the core is greater than that of the sheathing. Frequently, the core is the same polymer as that which comprises the sheathing but, in addition includes a non-polymeric substance (commonly referred to as a dopant) which causes the refractive index of the core to be greater than that of the sheathing. See for example, U.S. Pat. No. 5,541,247 to Koike.
However, currently available methods of fabrication have significant shortcomings. For example, the type and amount of substances which can be incorporated into the core and still provide a graded index plastic optical material which maintains both transparency and an acceptable difference in the refractive index between the sheathing and the core, are limited. Therefore, a need exists for methods and materials useful for fabricating graded index plastic optical materials.
SUMMARY OF THE INVENTION
The present invention is based upon the discovery that, surprisingly, a graded index plastic optical material having excellent optical characteristics can be achieved using a method of manufacturing, which incorporates a low refractive index dopant (i.e., lower than the polymer of the sheathing) in the sheathing of the material.
The present invention thus relates to a graded index plastic optical material, and methods of processing the material. The method of the invention provides for the use of a significantly broader selection of materials which consequently provides a graded index plastic optical fiber with excellent optical characteristics. For example, the method of the invention allows control of the graded refractive index of the material and thereby produces a graded index plastic optical material with a low loss and broad transmission bandwidth, having a high level of transparency, a substantial absence of bubbles and good environmental stability, for example, enhanced thermal stability and resistance to humidity.
A method for forming a graded index plastic optical material comprises the steps of: (a) providing a transparent tube of sheathing material comprising a sheathing polymer and a sheathing dopant; and (b) forming a transparent core within the sheathing tube produced in step (a) by: (i) filling the interior space of the sheathing tube, with a core solution comprising a core polymerizable monomer which upon polymerization has a refractive index greater than that of the sheathing tube; and (ii) allowing the core polymerizable monomer to polymerize thereby forming a polymer having a refractive index greater than that of the sheathing tube such that the material is suitable to conduct light. The core solution can comprise an optional core dopant. When present, the core dopant will have a refractive index greater than that of the polymer obtained upon polymerization of the core monomer. The product thus obtained, is a graded index plastic optical material having an outer transparent sheathing and an inner transparent core. The refractive index of the core is greater than that of the sheathing such that the material is suitable to conduct light, with the refractive index of the core gradually decreasing in a radial direction from the center of the core to the periphery. In general, the material is in the shape of a preform rod. Preferably, the preform rod has a cylindrical shape which can be drawn into fibers.
In a preferred embodiment, the sheathing tube is made by extrusion methods. Alternatively, the sheathing tube can be produced by: (a) placing into a polymerization container a sheathing solution comprising a sheathing polymerizable monomer and a sheathing dopant, the sheathing dopant having a refractive index lower than that of the polymer obtained by the polymerization of the sheathing monomer; and (b) causing the sheathing monomer of the sheathing solution to polymerize within the polymerization container in a cylindrical configuration to form a transparent sheathing tube.
The invention further provides a method for forming a graded index plastic optical fiber. The graded index plastic optical material is prepared, for example, as described above, in the shape of a preform rod which can then be subjected to hot-drawing at a temperature and speed suitable to render the fiber useful as an optical conductor.
In a certain embodiment, the monomer of the sheathing solution and the monomer of the core solution are the same. Suitable monomers include those which form polymers that are substantially amorphous and capable of conducting light in the desired wavelength. In this embodiment, when a core dopant is used it will be different from the sheathing dopant.
The graded index plastic optical material of the invention comprises (a) a transparent sheathing comprising a sheathing polymer and a sheathing dopant, wherein the sheathing dopant has a refractive index which is less than that of the sheathing polymer; and (b) a transparent core, disposed within the sheathing, comprising a core polymer having a refractive index greater than that of the sheathing and an optional core dopant, the core dopant, when present, having a refractive index which is greater than that of the core polymer; wherein the core dopant has a concentration gradient in a specific direction. The refractive index of the core is greater than that of the doped sheathing.
In a preferred embodiment, the material is in the shape of a cylindrical preform rod. In another application the material is in the shape of a cylindrical fiber having an outer diameter between about 0.2 millimeters and about 1 millimeter.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a preferred embodiment of a graded index plastic optical material producible by the process of the invention.
FIG. 2 is a graph showing the relationship between the transmission loss and wavelength of an optical fiber. The transmission loss was measured using standard techniques as described herein. Transmission loss at 650 nm was approximately 140 dB/km demonstrating that the optical fiber had a high level of transparency.
DETAILED DESCRIPTION OF THE INVENTION
The features and other details of the invention will now be more particularly described and pointed out below as well as in the claims. It will be understood that the particular embodiments of the invention are shown by way of illustration and not as limitations of the invention. The principle features of this invention can be employed in various embodiments without departing from the scope of the invention.
In one aspect, the invention provides a method for forming a graded index plastic optical material comprising the steps of: (a) forming a transparent tube of sheathing material by: (i) placing into a polymerization container a sheathing solution comprising a sheathing polymerizable monomer and a sheathing dopant, wherein the sheathing dopant has a refractive index lower than that of the polymer obtained by the polymerization of the sheathing monomer; and (ii) causing the sheathing monomer of the sheathing solution to polymerize within the polymerization container to give an inner cylindrical configuration in the form of a transparent sheathing tube; and (b) forming a transparent core within the sheathing tube produced in step (a) by: (i) filling the interior space of the sheathing tube with a core solution comprising a core polymerizable monomer which upon polymerization has a refractive index greater than that of the sheathing tube; and (ii) allowing the core polymerizable monomer to polymerize thereby forming a polymer having a refractive index greater than that of the sheathing tube such that the material is suitable to conduct light. The core solution can comprise an optional core dopant. When present, the core dopant will have a refractive index greater than that of the polymer obtained upon polymerization of the core monomer.
The product thus obtained, is a graded index plastic optical material having an outer transparent sheathing layer and an inner transparent core. The refractive index of the core is greater than that of the sheathing such that the material is suitable to conduct light, with the refractive index of the core gradually decreasing in a radial direction from the center of the core to the periphery. In general, the material is in the shape of a preform rod, as shown in FIG. 1, where the transparent sheathing is depicted as component 1 and the core is depicted as component 2. Preferably, the preform rod has a cylindrical shape.
The method also provides for forming a graded index plastic optical fiber. This comprises formation of a graded index plastic optical material, for example, as described above, in the shape of a preform rod followed by hot-drawing of the preform at a temperature and speed suitable to render the fiber useful as an optical conductor.
The term "preform rod" as used herein is the rod shaped form of the graded index plastic optical material that can be produced according to the method of the present invention. In general, the rod can be further processed into an optical conductor such as an optical fiber, an optical waveguide or an optical integrated circuit. For example, after the preform rod is produced, it can be removed from the polymerization container and formed into a plastic optical fiber. This can be accomplished, for example, by hot-drawing of the preform. Other known fiber producing techniques, for example, extrusion can also be employed.
The polymerization container used in the method of the invention can be composed of any material which is inert to the sheathing solution, for example, glass. The container shape and dimensions will determine the outer shape of the graded index plastic optical material ultimately obtained in the practice of the method. A sheathing tube is produced, using the well known technique of rotation casting, by placing a sheathing solution in the polymerization container and causing the solution to polymerize within the container to give an inner cylindrical configuration. Thus, the polymerization container can be any shape which when rotated about its own axis creates a sheathing tube with an inner cylindrical configuration. The preferred shape of the container is cylindrical, preferably with dimensions that can achieve a preform rod suitable for hot-drawing into an optical fiber.
The sheathing of the graded index optical material is the outer layer of the material. The sheathing is prepared using the well known technique of rotation casting, by placing into a polymerization container a sheathing solution comprising a sheathing polymerizable monomer and a sheathing dopant and causing the sheathing polymerizable monomer of the sheathing solution to polymerize within the container in a cylindrical configuration. The sheathing dopant does not participate in the polymerization reaction. Polymerization of the monomer into a cylindrical configuration can be accomplished by, for example, rotating the polymerization container about its own axis, during polymerization. The centrifugal force resulting from the rotation will cause the resulting polymer to form a tube of sheathing material or a sheathing tube within the polymerization container. Rotation can be accomplished, for example, by spinning the container.
Alternatively, the sheathing can also be prepared by extrusion of the doped sheathing polymer into tubular shapes using extrusion methods which are well known to those of skill in the art. The outer and inner shape of the sheathing in this method will be dictated by the shape of the extrusion dye. The extruded sheathing will then serve as the container into which the core solution will be added and allowed to polymerize.
The amount of sheathing solution placed in the polymerization container can be determined based upon the ratio of the thickness of the sheathing wall to the distance between the opposing interior walls of the sheathing, which is desired. This ratio will depend upon the cost of materials and the end use of the optical material.
The polymerizable sheathing monomer can be any monomer which upon polymerization yields substantially amorphous and transparent polymeric materials. Preferably, the polymeric materials of the sheathing are at least partially soluble in the monomer present in the core solution and exhibit a suitable miscibility with the sheathing dopant.
Polymerizable monomers suitable for use in this invention include, but are not limited to, for example, methacrylate monomers such as branched and unbranched C 1 -C 10 alkyl methacrylates, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, n-hexyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate; halogenated methacrylates, such as 2,2,2-trifluoroethyl methacrylate; 4-methyl cyclohexyl methacrylate, cyclohexyl methacrylate, furfuryl methacrylate, 1-phenylethyl methacrylate, 2-phenylethyl methacrylate, 1-phenylcyclohexyl methacrylate, benzyl methacrylate and phenyl methacrylate; acrylate monomers such as, methyl acrylate, ethyl acrylate, n-butyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, methyl-α-chloro acrylate, 2,2,3,3-tetrafluoropropyl-α-fluoro acrylate, and 2,2,2-trifluoroethyl acrylate; acrylonitrile and α-methylacrylonitrile; vinyl monomers such as, vinyl acetate, vinyl benzoate, vinyl phenylacetate, vinyl chloroacetate; styrene monomers such as, styrene, halogenated styrenes, for example, o-chlorosytrene, p-fluorostyrene, o,p-difluorostyrene, and p-isopropyl styrene; perfluorinated monomers such as 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole also known as perfluoro(2,2-dimethyl-1,3-dioxole) (PDD), and any combination of monomers thereof. When a combination of monomers is employed polymerization will result in formation of a copolymer.
A sheathing dopant suitable for use in the methods of the invention is one which does not participate in the reaction which polymerizes the sheathing monomer. A suitable sheathing dopant will have a refractive index which is lower than that of the polymer obtained upon polymerization of the sheathing monomer of the sheathing solution. In addition, the sheathing dopant must not compromise the transparency of the polymer obtained upon polymerization of the sheathing monomer. The level of transparency is inversely related to the transmission loss of a graded index plastic optical conductor in the operating wavelength of the conductor, and can be assessed using techniques known to those of skill in the art. For example, a graded index plastic optical fiber which has a transmission loss value of 110 dB/km at an operating wavelength of 650 nm, possesses an adequate level of transparency as an optical conductor. However, a loss of more than 500 dB/km would not be an acceptable level of transparency. Therefore, a graded index optical material is transparent when an optical conductor, prepared from the material, has a transmission loss, also known as the attenuation, in the operating wavelength of the conductor less than 500 dB/km. FIG. 2 depicts the transmission loss of an optical fiber prepared using t#he method of the invention as described herein in Example 1. The loss was measured using methods known in the art such as those described in "Test Method for Attenuation of All Plastic Multimode Optical Fibers JIS C 6863-(1990)," Japanese Industrial Standard by the Japanese Standards Association. FIG. 2 shows a transmission loss of 140 dB/km at a wavelength of 650 nm. This transmission loss provides a fiber with a suitable level of transparency.
One useful criterion, for predicting whether or not the sheathing will be transparent, is predicated on the Flory-Huggins interaction parameter, X AB . That is, X AB can be used as a guide to the likelihood of miscibility between substances A and B, which in this case would be sheathing polymer and sheathing dopant. The blend miscibility can be assumed to decrease with increasing values of X AB . This parameter can be determined experimentally or approximated according to the following equation: ##EQU1## δ, is the solubility parameter which is a thermodynamic quantity generally defined as the square root of the cohesive energy density. The cohesive energy density is obtained by dividing the molar evaporation energy, ΔE, of a liquid by a molar volume, V. V ref is an appropriate reference volume. R is the gas constant and T is the temperature. A detailed discussion of the Flory-Huggins interaction parameter can be found in CRC Handbook of Polymer-Liquid Interaction Parameters and Solubility Parameters, by A. F. M. Barton, 1990.
However, the Flory-Huggins interaction parameter should be used as a guide to the selection of an appropriate dopant, but not as a limitation, since the concentration of the dopant is also an important criterion to consider in maintaining a sheathing and core with an acceptable transparency.
Some examples of sheathing dopants suitable for use in the invention include, but are not limited to, diisobutyl adipate, glycerol-triacetate, 2,2,4-trimethyl -1,3-pentanediol diisobutyrate, methyl laurate, dimethyl sebatate, isopropyl myristate, diethyl succinate, diethyl phthalate, tributyl phosphate, dicyclohexyl phthalate, dibutyl sebatate, diisooctyl phthalate, dicapryl phthalate, diisodecyl phthalate, butyl, octyl phthalate, dicapryl adipate, perfluorinated aromatics, for example perfluoro naphthalene, perfluorinated ethers and perfluorinated polyethers. Typically, the sheathing dopant is present in the sheathing at a concentration of between about 1 and about 35 weight percent of the monomer of the sheathing solution, more typically between about 1 and about 20 weight percent and most typically between about 1 and about 15 weight percent.
In general, the sheathing dopant can impart plasticizer-like qualities and/or hydrophobic properties upon the graded index plastic optical material. The presence of plasticizer-like qualities and/or hydrophobic properties in the graded index plastic optical material of the invention is advantageous. That is, plasticizer-like qualities allow the graded index plastic optical material to be hot-drawn at a lower temperature and a higher speed, which results in a fiber with an acceptable level of attenuation or transmission loss. Hydrophobic properties provide for an optical material with enhanced environmental stability, for example, decreased moisture absorbency.
Any method of polymerization can be used in the method of the invention for forming the graded index plastic optical material. These methods include, for example, free radical polymerization, atom transfer radical polymerization, anionic polymerization and cationic polymerization. Free radical bulk polymerization, employing either thermal or optical energy, is preferred.
When radical polymerization is employed, the sheathing solution also includes a radical polymerization initiator and a chain transfer agent. Suitable radical polymerization initiators are selected based on the type of energy employed in the polymerization reaction. For example, when heat or infrared polymerization is employed peroxides such as lauryl peroxide, benzoyl peroxide, t-butyl peroxide and 2,5-dimethyl-2,5-di(2-ethyl hexanoyl peroxy)hexane (TBEC) are suitable for use. When ultraviolet polymerization is employed benzoin methyl ether (BME) or benzoyl peroxide is suitable for use. Typically, the polymerization initiator is present in the sheathing solution in a range of between about 0.1 to about 0.5 percent by weight of the monomer.
Any chain transfer agent is suitable for use in the method of the invention. These include, but are not limited to, 1-butanethiol and 1-dodecanethiol. Typically, the chain transfer agent is present in the sheathing solution below about 0.5 percent by weight of the monomer.
As described earlier, the polymerization container is rotated during polymerization of the monomer of the sheathing solution. This rotation, for example, spinning, provides a transparent sheathing tube having an inner cylindrical configuration. The interior space of this sheathing tube thereby provides a suitable container for polymerization of the core monomer in a subsequent step of the claimed method.
The core of the graded index plastic optical material is the inner layer of the material which is disposed within the sheathing. The core is transparent and ultimately provides the component of the material through which light travels. The refractive index of the core is greater than that of the sheathing such the material is suitable to conduct light.
The core can be prepared by filling the sheathing tube with a core solution which comprises a core polymerizable monomer and an optional core dopant, and polymerizing the core monomer. The core polymerizable monomer can be any monomer which upon polymerization yields substantially amorphous and transparent polymeric materials capable of conducting light in the desired wavelength. In addition, the core polymerizable monomer, upon polymerization, has a refractive index greater than that of the sheathing such that the material is suitable to conduct light. All of the monomers which are suitable for use in preparing the sheathing are, likewise, suitable for use in preparing the core. A combination of monomers can also be used in preparation of the core thereby providing a core comprising a copolymer.
As described earlier, any method of polymerization is suitable for use in the method of the invention. When radical polymerization is employed in preparation of the core, a polymerization initiator is present in the core solution in ranges similar to those described earlier for the sheathing solution. Typically, the chain transfer agent is present below about 0.5 percent by weight of the monomer.
A core dopant suitable for use in the method of the invention is one which does not participate in the reaction which polymerizes the core monomer and which has a boiling point lower than the highest processing temperature to which it is subjected. A suitable core dopant will have a refractive index which is greater than that of the polymer obtained upon polymerization of the core monomer. In addition, the core dopant must not compromise the transparency of the polymer obtained upon polymerization of the core monomer. As in the preparation of the sheathing, one useful criterion for predicting whether or not the core will be transparent is predicated on the Flory-Huggins interaction parameter, between the core polymer and the core dopant. However, as discussed earlier this parameter should be used only as a guide not a limitation when choosing a suitable core dopant, since the concentration of the dopant also needs to be considered.
Compounds suitable for use as the core dopant in the method of the invention include, but are not limited to, dibenzyl ether, phenoxy toluene, 1,1-bis-(3,4-dimethyl phenyl) ethane, diphenyl ether, biphenyl, diphenyl sulfide, diphenylmethane, benzyl phthalate-n-butyl, 1-methoxyphenyl-1-phenylethane, benzyl benzoate, bromobenzene, o-dichlorobenzene, m-dichlorobenzene, 1,2-dibromomethane, 3-phenyl-1-propanol, dioctyl phthalate and perfluorinated aromatics, such as, perfluoro naphthalene.
When the core solution, which comprises the core monomer and an optional core dopant, is added to the sheathing tube, the inner surface of the sheathing tube, is slightly swollen by the core monomer. As a result, a gel phase is formed on the inner wall of the sheathing tube. The concentration of the polymer in the swollen phase layer is not uniform, in that the concentration of the polymer and sheathing dopant, eluted from the sheathing, gradually decreases with distance from the inner surface. Thus, a distributed concentration of the low refractive index dopant is formed in the gel phase due to diffusion of sheathing dopant. Polymerization starts from the vicinity of the inner surface of the sheathing and gradually grows to the center axis of the tube due to accelerated polymerization in the gel stated commonly known as the "gel-effect" (See for example, Koike, Y. et al., "High-Bandwidth Graded-Index Polymer Optical Fiber," Journal of Lightwave Technology, 13(7): 1475-1489 (1995) and Koike, Y. et al., "New Interfacial-Gel Copolymerization Technique for Steric GRIN Polymer Optical Waveguide and Lens Arrays," Applied Optics, 27(3): 486-491 (1988)).
When a core dopant is present, a concentration gradient of the core dopant, which remains in the core polymer, is also formed. As described in U.S. Pat. No. 5,541,247 by Koike, the core monomer polymerizes while the substance with a greater refractive index becomes highly concentrated at the center of the core. The high concentration of the core dopant which is present at the central part of the core gradually decreases in a radial direction toward the periphery, thereby, creating a gradient in a specific direction.
In a certain embodiment, the monomer of the sheathing solution and the monomer of the core solution are the same. Suitable monomers include those which form polymers that are substantially amorphous and transparent, thereby being capable of conducting light in the desired wavelength, as earlier described. When the sheathing and core monomers are the same, and a core dopant is present, the sheathing and core dopants will be different. That is, the sheathing dopant will have a refractive index which is less than that of the polymer obtained upon polymerization of the sheathing monomer while the core dopant will have a refractive index which is greater than that of the polymer obtained upon polymerization of the core monomer. However, the difference in refractive index between the sheathing dopant and core dopant should have a value which renders the optical material suitable to conduct light.
This difference in the refractive index could be, for example, 0.001 and be achieved by, for example, employing a core dopant with a refractive index greater than that of the core polymer by 0.0005 and a sheathing dopant with a refractive index less than of the sheathing polymer by 0.0005. Thus, the method of the invention has advantages over a method employing a dopant-free sheathing, in that a broader selection of materials which can employed as dopants is available, based on the additive effect of the core and sheathing dopant as opposed to the singular effect of the core dopant. Additionally, a lower concentration of dopant or no dopant at all can be used in the core and still achieve a comparable difference in refractive index.
In a specific embodiment, the monomer of the core and the sheathing is methyl methacrylate. In this embodiment, when a core dopant is present, the sheathing and core dopants are different substances. The difference in the refractive index between the dopants must be such that the optical material is suitable to conduct light. Additionally, the refractive index of the core dopant is greater than that of the sheathing dopant. For example, the dopant for the sheathing can be tributyl phosphate (refractive index=1.424) while the dopant for the core can be diphenyl sulfide (refractive index=1.6327).
In another embodiment, the monomer of the core and the sheathing is 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole also known as perfluoro(2,2-dimethyl-1,3-dioxole) (PDD). In this embodiment, when a core dopant is present, the sheathing and core dopants are different substances, with the difference in the refractive index between the dopants such that the optical material is suitable to conduct light. Additionally, the refractive index of the core dopant is greater than that of the sheathing dopant.
In yet another embodiment, the method of the invention further comprises the step of hot-drawing the graded index optical preform into a fiber. Typically, hot-drawing is conducted at a temperature suitable to sufficiently soften the preform rod to allow it to be drawn into a fiber. The drawing is generally conducted at a speed suitable to render the fiber useful as an optical conductor.
In yet another aspect, the invention provides a graded index plastic optical material comprising: (a) a transparent sheathing comprising a sheathing polymer and a sheathing dopant, wherein the sheathing dopant has a refractive index which is less than that of the sheathing polymer; and (b) a transparent core, disposed within the sheathing, comprising a core polymer having a refractive index greater than that of the sheathing and an optional core dopant, the core dopant, when present, having a refractive index which is greater than that of the core polymer; wherein the core dopant has a concentration gradient in a specific direction. The refractive index of the core is greater than the doped sheathing.
In a preferred embodiment, the graded index plastic optical material is in the shape of a cylindrical preform rod. In another application, the graded index plastic optical material is in the shape of a cylindrical fiber having an outer diameter between about 0.2 millimeters and about 1 millimeter. The fiber can be prepared, for example, by hot-drawing a preform rod, the fiber maintaining the same geometry of the preform but, with a smaller outer diameter.
In certain embodiments, the graded index plastic optical material has the same polymer in both the sheathing and the core. In this particular embodiment, when the optional core dopant is present, the core dopant and the sheathing dopant are different substances. The sheathing dopant has a refractive index which is less than that of the core dopant. The difference in refractive index between the dopants should be such that resulting optical material is suitable to conduct light. For example, the material should be useful as an optical conductor. For example, when the polymer of the core and sheathing is poly(methyl methacrylate), the sheathing dopant can be tributyl phosphate (refractive index=1.424) and the core dopant can be diphenyl sulfide (refractive index=1.6327). When the polymer of the core and sheathing is, for example, that obtained upon polymerization of the monomer 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole, the sheathing dopant and core dopant are different substances, with the difference in the refractive index between the dopants such that the optical material is suitable to conduct light. In addition, the refractive index of the core dopant is higher than the sheathing dopant with both dopants being perhalogenated.
The advantages of the method of the invention include the availability of a significantly broader range of materials which are useful in preparing a graded index plastic optical material. This increase in the types of materials suitable for use in the invention provides, for example, the ability to increase the difference in the refractive index between the sheathing and the core without compromising the characteristics of the optical material and the ability to widen the operating wavelength of the material particularly when employed in data communications. In addition, the concentration of dopant in the core, necessary to provide the required difference in refractive index, can be decreased when a sheathing dopant, having a lower refractive index than the sheathing polymer, is present. This decrease in the concentration of the core dopant significantly improves the miscibility of materials which directly impacts the optical characteristics, for example, transparency of the optical material. Further, the sheathing dopant, in many instances, behaves as a plasticizer in the graded index plastic optical material. This plasticizer-like behavior allows for hot-drawing of the material, for example, in the shape of a preform rod at a lower temperature and/or higher speed.
The invention will now be further illustrated by the following examples which are not intended to limit the scope of the invention in any way. All percentages are by weight unless otherwise specified.
EXEMPLIFICATION
EXAMPLE 1
PREPARATION OF SHEATHING
A sheathing solution containing 1600 g of purified methyl methacrylate (MMA), 4.00 g (0.25 weight percent of MMA) of lauryl peroxide as the polymerization initiator, 3.42 ml of 1-butanethiol (0.18 weight percent of MMA) as the chain transfer reagent (available from Aldrich Chemical Co., Inc., Milwaukee, Wis.) and 128 g (8 weight percent of MMA) of dicyclohexyl phthalate was stirred and degassed for about 30 minutes.
To an appropriately stoppered glass tube, having an inner diameter of 30 mm and a length of 1.5 meters was added sheathing solution, to the appropriate height to achieve the desired final ratio of core to sheathing thickness. For example, a final ratio of the thickness of the sheathing wall to core thickness can be between about 1:4 to about 2:1. Both ends of the tube were sealed, and then the tube was placed in a water bath at a temperature of 71° C. and polymerized while being rotated at approximately 500 rpm for 20 hours. The tube was then placed in a rotating oven (approximately 5 rpms) for two hours at 100° C. A poly(methyl methacrylate) sheathing tube was prepared.
PREPARATION OF CORE
The sheathing prepared above was kept in the glass tube, and the container formed by the cylindrical inner surface of the sheathing was filled with a solution containing 350 g of MMA, 200 microliters of t-butyl peroxide, 600 microliters of 1-dodecanethiol and 30 grams (8.5 weight percent) of diphenyl sulfide. The tube was sealed and then heated in a vertical position at 90° C. for at least 12 hours. The tube was then placed in the oven horizontally and heated for 12 hours at 90° C., 24 hours at 110° C., 10 hours at 120° C. and 4 hours at 130° C. while rotating at a speed of 5 rpms.
The graded index plastic optical preform rod was then removed from the glass polymerization container. The rod was then slowly inserted into a cylindrical heating furnace from the top while the furnace was maintained at a temperature between 180° C. and 220° C. When the rod was softened sufficiently, spinning at a constant speed of approximately 5-15 meters/min was started from the bottom of the rod.
EXAMPLE 2
PREPARATION OF SHEATHING
A sheathing solution containing 1600 g of purified methyl methacrylate (MMA), 4.00 g (0.25 weight percent of MMA) of lauryl peroxide as the polymerization initiator, 3.42 ml of 1-butanethiol (0.18 weight percent of MMA) as the chain transfer reagent (available from Aldrich Chemical Co., Inc., Milwaukee, Wis.) and 320 g (20 weight percent of MMA) of dicyclohexyl phthalate was stirred and degassed for about 30 minutes.
To an appropriately stoppered glass tube, having an inner diameter of 30 mm and a length of 1.5 meters was added sheathing solution, to the appropriate height to achieve the desired final ratio of core to sheathing thickness. For example, a final ratio of sheathing to core thickness can be between about 1:4 to 2:1. Both ends of the tube were sealed, and then the tube was placed in a water bath at a temperature of 71° C. and polymerized while being rotated at approximately 500 rpm for 20 hours. The tube was then placed in a rotating oven (approximately 5 rpms) for two hours at 100° C. A poly(methyl methacrylate) sheathing tube was prepared.
PREPARATION OF CORE
The sheathing prepared above was kept in the glass tube, and the container formed by the inner surface of the sheathing was filled with a solution containing 350 g of MMA, 200 microliters of t-butyl peroxide and 600 microliters of 1-dodecanethiol. The tube was sealed and then heated in a vertical position at 90° C. for at least 12 hours. The tube was then placed in the oven horizontally and heated for 12 hours at 90° C., 24 hours at 110° C., 10 hours at 120° C. and 4 hours at 130° C. while rotating at a speed of 5 rpms.
The graded index plastic optical preform rod was then removed from the glass polymerization container. The rod was then slowly inserted into a cylindrical heating furnace from the top thereof while the furnace was maintained at a temperature between 180° C. and 220° C. When the rod was softened sufficiently, spinning at a constant speed of approximately 5-15 meters/min was started from the bottom of the rod.
EQUIVALENTS
Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims. | 4y
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to capacitors, and more particularly, to capacitors that may be embedded within printed circuit boards or other microelectronic devices.
2. Background of the Invention
Capacitors are devices used for introducing capacitance into a circuit. Capacitors function primarily to store electrical energy, block the flow of direct current, or permit the flow of alternating current. They comprise a layer of dielectric material sandwiched between a pair of spaced conductive metal layers, such as copper foils.
Capacitors are common elements on printed circuit boards (PCBs) and other microelectronic devices. In recent years, substantial efforts have been expended in the design of such PCBs and devices arranged thereupon to compensate for voltage fluctuations arising between the power and ground planes in the PCBs. One common type of voltage fluctuations include “switching noises,” which may be caused by switching operation of transistors in the integrated circuits. A common solution to this problem is to place one or more capacitors serving as a decoupling capacitors or bypass capacitors, which may be coupled between the power and ground terminals in proximity to the integrated circuits.
Capacitors may be electrically connected either as discrete elements on a circuit board, or may be embedded within the circuit boards. Of these options, forming embedded capacitors within the circuit boards allows increased surface area of the board for other purposes.
Two main factors for selection of a capacitor include the capacitance and the frequency bandwidth of a capacitor. The frequency bandwidth of a capacitor depends on its self-resonance frequency because a capacitor behaves properly when it operates in a frequency below the self-resonance frequency. Equation (1) below shows the relationship between capacitance and self-resonance frequency of a capacitor:
f r = 1 2 π L C ( 1 )
where f r represents the self-resonance frequency, L represents the parasitic inductance (i.e., equivalent series inductance “ESL”), and C represents the parasitic capacitance (i.e., equivalent series capacitance “ESC”). According to Eq. (1), a capacitor with smaller capacitance may have higher self-resonance frequency, thereby having a broad frequency bandwidth. On the other hand, a capacitor with larger capacitance may have lower self-resonance frequency, thereby having a narrow frequency bandwidth. However, for decoupling capacitors, it is highly desirable to have a high self-resonance frequency and high capacitance.
Capacitance, in general, can be determined by the equation below:
C = ɛ A d ( 2 )
where C represents the capacitance of the capacitor in Farads, ∈ represents the dielectric constant of the dielectric material, and A represents the surface area of the dielectric material held between two conducting plates and d represents the distance between the plates. According to Eq. (2) above, capacitance is proportional to the surface area of the conducting plates and the dielectric constant of the dielectric material, and inversely proportional to the distance between the plates. Thus, in order to increase the capacitance of a capacitor, one may increase the area of the conducting plates or select an extremely thin layer of a dielectric material with a high dielectric constant. However, each of these approaches presents difficulties. First, increasing the area of the conducting plates departs from the object of compact designs. In addition, the selection of the dielectric material is often limited by many production and configuration limitations. Additional difficulties arise when the thickness of a dielectric layer is reduced. In particular, the thickness of a dielectric layer on a circuit board can be difficult to control because dielectric thickness may be dramatically changed due to the shapes and dimensions of the patterned features (e.g., capacitor electrodes) over which dielectric is deposited. A thin-dielectric layer design usually comes with the danger of having metal-to-metal shorting through the thin dielectric layer and of having microscopic voids or other structural defects in the layer that may impact capacitive effects and characteristics.
BRIEF SUMMARY OF THE INVENTION
Examples consistent with the present invention may provide a capacitor device with a capacitance and a method of fabricating a capacitor.
One example of the present invention provides a capacitor device with a capacitance comprising at least one capacitive element. The at least one capacitive element comprises a pair of first conductive layers being opposed to each other, at least one first dielectric layer formed on a surface of at least one of the first conductive layers, and a second dielectric layer being sandwiched between the first conductive layers. The first dielectric layer has a first dielectric constant and the second dielectric layer has a second dielectric constant. The capacitance of the capacitor device depends on dielectric parameters of the first dielectric layer and the second dielectric layer. The dielectric parameters comprise the first dielectric constant and thickness of the at least one first dielectric layer and the second dielectric constant and thickness of the second dielectric layer.
Another example of the present invention provides a method of fabricating a capacitor comprising providing a pair of first conductive layers, forming at least one first dielectric layer on one of the first conductive layers, and laminating the first conductive layers and the at least one first dielectric layer with a second dielectric layer.
One example consistent with the present invention provides a capacitor device comprising a number of capacitive elements. At least one of the capacitive elements comprises a first conductive layer and a second conductive layer being opposed to the first conductive layer, at least one first dielectric layer formed on a surface of at least one of the first and the second conductive layers, and a second dielectric layer being sandwiched between the first and the second conductive layers via the at least one first dielectric layer. The first dielectric layer has a first dielectric constant and the second dielectric layer has a second dielectric constant. At least one of the first and the second conductive layers of the capacitive element is coupled to a conductive layer of another capacitive element.
Another example consistent with the present invention provides a capacitor device having a number of capacitive elements. The capacitor device comprises a first capacitive element comprising a pair of first conductive layers being opposed to each other, at least one first dielectric layer formed on a surface of at least one of the first conductive layers, and a second dielectric layer being sandwiched between the first conductive layers via the at least one first dielectric layer. The capacitor device further comprises a second capacitive element comprising a pair of second conductive layers being opposed to each other, at least one third dielectric layer formed on a surface of at least one of the second conductive layers, and a fourth dielectric layer being sandwiched between the second conductive layers via the at least one third dielectric layer. The at least one first dielectric layer has a first dielectric constant and the at least one third dielectric layer has a third dielectric constant. The third dielectric constant being different from the first dielectric constant.
One example consistent with the present invention provides a capacitor device with a capacitance. The capacitor device comprises a pair of first conductive layers being opposed to each other, and a dielectric layer being sandwiched between the first conductive layers. The dielectric layer comprises at least a first dielectric material with a first dielectric constant and a second dielectric material with a second dielectric constant different from the first dielectric constant to form at least two capacitive elements in parallel sharing the first conductive layers.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended, exemplary drawings. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
In the drawings:
FIGS. 1( a )-( d ) are cross-sectional views of a metal-insulator-metal capacitor in the prior art;
FIGS. 2( a )-( f ) are cross-sectional views of a metal-insulator-metal capacitor in examples consistent with the present invention;
FIGS. 3( a )-( b ) are cross sectional views of a metal-insulator-metal capacitor in examples consistent with the present invention;
FIG. 3( c ) is an equivalent electrical circuit of structure of FIG. 3( b );
FIG. 3( d ) is an impedance curve of a capacitor of FIG. 3( b );
FIGS. 4( a )-( b ) are cross sectional views of a metal-insulator-metal capacitor in examples consistent with the present invention;
FIG. 4( c ) shows equivalent structure of FIG. 4( b );
FIGS. 5( a )-( e ) are cross sectional views of a metal-insulator-metal capacitor in examples consistent with the present invention;
FIG. 6( a ) is a cross sectional views of a metal-insulator-metal capacitor in examples consistent with the present invention;
FIG. 6( b ) is an equivalent electrical circuit of structure of FIG. 6( a );
FIG. 6( c ) is an impedance curve of a capacitor of FIG. 6( a );
FIG. 6( d ) is an impedance curve of three SMD capacitors in parallel; and
FIGS. 7( a )- 7 ( c ) show a capacitive core in examples consistent with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
U.S. Pat. No. 5,800,575 describes one method of fabricating a metal-insulator-metal (MIM) capacitor. Referring to FIG. 1( a ), the fabrication process may start from forming an initial lamination product 50 which includes the fully cured dielectric sheet 40 ′ with conductive foils 28 ′ and 46 ′ laminated or bonded on opposite sides of the dielectric sheet 40 ′. Thereafter, the conductive foil 28 ′ is etched as indicated in FIG. 1 ( b ). Referring to FIG. 1( c ), another lamination product 52 is formed in a similar manner as the lamination product 50 . The lamination product 52 includes the other dielectric layer 42 ′ and the conductive foils 30 ′ and 48 ′. An uncured dielectric sheet 32 ′ is then arranged between the lamination products 50 and 52 so that it is adjacent to both the conductive foils 28 ′ and 30 ′. After a conventional lamination to convert the uncured dielectric sheet 32 ′ to a fully cured condition, the finished capacitive PCB 10 ′ is formed as shown in FIG. 1( d ). The thickness of the dielectric sheet 32 ′ is usually reduced in order to obtain large capacitance. However, a thin-dielectric sheet design may cause undesirable metal-to-metal shorting through the thin dielectric sheet.
One example of the present invention provides a capacitor which comprises at least one dielectric layer coated on at least one of the conductive layers serving as electrodes of a capacitor, prior to lamination with an intermediate dielectric layer. In this manner, the conductive layers are protected by the at least one dielectric layer from contacting each other. FIGS. 2( a )-( f ) show methods of fabricating a metal-insulator-metal capacitor in examples consistent with the present invention. The fabrication process may include forming an initial structure 210 which includes a carrier 212 and a conductive layer 214 . In some examples, the carrier 212 may include prepreg, which may be a reinforced material impregnated with epoxy resin or fiber-reinforced material coated with epoxy. In one example, the carrier 212 may have a thickness between about 9 μm to 36 μm and is made of one or more conductive materials, such as copper. The conductive layer 214 may be etched as shown in FIG. 2( a ). The conductive layer appropriate for the purpose of the present invention may vary depending on the desired applications. In some examples, the conductive layer 214 may include a material selected from the group consisting of copper, zinc, brass, chrome, chromates, titanium nitride, nickel, silanes, aluminum, stainless steel, iron, gold, silver, titanium, and combinations thereof. In one example, the conductive layer 214 may include or be made of copper, and its thickness may be in the range from 5 μm to 75 μm.
As shown in FIG. 2( a ), similar to structure 210 , another initial structure 220 is formed to include a carrier 222 and a conductive layer 224 . Prior to lamination of the structures 210 and 220 with an intermediate dielectric layer 230 , another dielectric layer is formed on at least one of the conductive layers 214 and 224 . For example, a dielectric layer 226 is formed on the conductive layers 224 as shown in FIG. 2( a ) and dielectric layers 216 and 226 are formed on one of the conductive layers 214 and one of the conductive layers 224 as shown in FIG. 2( c ). In another example, two dielectric layers 216 and 226 are formed on the both conductive layers 214 and 224 as shown in FIG. 2( e ). The dielectric layer may be formed by screen printing, inkjet printing, or any other technique that may provide a thin dielectric layer. The dielectric layer may include a dielectric material having a dielectric constant as high as several hundred and may have a thickness of about 5 μm, but the thickness may be varied depending on the various applications. Examples of high dielectric constant or high K materials may include epoxies, polyesters, polyester containing copolymers, aromatic theromosetting copolyesters, polyarylene ethers and fluorinated polyarylene ethers, polyimides, benzocyclobutenes, liquid crystal polymers, allylated polyphenylene ethers, amines, inorganic materials such as barium titanate (BaTiO 3 ), boron nitride (BN), aluminum oxide (Al 2 O 3 ), silica, strontium titanate, barium strontium titanate, quartz and other ceramic and non-ceramic inorganic materials and combinations thereof.
After the at least one dielectric layer is applied to one of the conductive layers 214 and 224 , the two structures 210 and 220 may be pressed against the intermediate dielectric layer 230 to form a structure as illustrated in FIGS. 2( b ), 2 ( d ) or 2 ( f ), where portions of the intermediate dielectric layer 230 are sandwiched between the conductive layers 214 and 224 via at least one dielectric layer 216 and/or 226 . The dielectric layer 230 may be a dielectric material with a high dielectric constant as described above. In one example, the dielectric constant of the dielectric layer 230 may be lower than the dielectric constant of the dielectric layer 216 and/or 226 . The thickness of the dielectric layer 230 may be about 20 μm.
With the capacitor design illustrated above, the conductive layers 214 and 224 are protected by the dielectric layer 216 and/or 226 from making contacts or shorting with each other. In addition, by having a dielectric structure comprising the dielectric layer 230 and the dielectric layer 216 or 226 , the dielectric constant of the dielectric structure may be controlled by the intermediate dielectric layer 230 , and the dielectric layers 216 and 226 . In addition, the capacitance depends on the thickness of the dielectric layers 216 and/or 226 and the intermediate dielectric layer 230 .
FIGS. 3( a ) and 3 ( b ) show fabrication of an MIM capacitor in examples consistent with the present invention. Referring to FIG. 3( a ), each of the structures 310 and 320 includes a carrier ( 312 or 322 ) and a conductive layer ( 314 or 324 ). On the patterned conductive layers 314 and 324 , dielectric layers are formed. The dielectric layers formed on the patterned conductive layers 314 and 324 may have different dielectric constants by having different dielectric materials or different combination of dielectric materials. In one example, the dielectric layer 316 a has the same dielectric constant as the dielectric layer 326 a while the dielectric layer 316 b has the same dielectric constant as the dielectric layer 326 b . After lamination of the structures 310 and 320 with the intermediate dielectric layer 330 , capacitors C 1 and C 2 are formed as shown in FIG. 3( b ). Since the dielectric constant for the capacitor C 1 is different from the dielectric constant for the capacitor C 2 , the capacitors C 1 and C 2 have different capacitance. An equivalent electrical circuit of FIG. 3( b ) is shown in FIG. 3( c ) where the capacitors C 1 and C 2 are connected in parallel. FIG. 3( d ) is the impedance curve of capacitors of FIG. 3( b ), which shows that, with capacitors in parallel, the bandwidth, such as the bandwidth for reducing or eliminating noises of different frequencies, for the capacitors may become broader.
FIGS. 4( a )-( b ) show an MIM capacitor consistent with examples of the present invention. Similar to FIG. 3( a ), each structure ( 410 or 420 ) includes a carrier ( 412 or 422 ), a patterned conductive layer ( 414 or 424 ), and a dielectric layer ( 416 or 426 ) on the patterned conductive layer. In addition, there are thin conductive layers 418 and 428 formed on each dielectric layer as shown in FIG. 4( a ). After lamination of the two structures 410 and 420 with the dielectric layer 430 , a capacitor with higher capacitance as shown in FIG. 4( b ) may be formed. As illustrated in FIG. 4( c ), the distance between the conductive layers 414 and 424 may be reduced by the thin conductive layers 418 and 428 . Accordingly, the capacitance may increase. In one example, a number of thin conductive layers may be included between the conductive layers 414 and 424 to reduce the distance between the conductive layers, thereby increasing the capacitance. The conductive layers and the thin conductive layers may include or be made of one or more of the conductive materials noted above. The thin conductive layers 418 and 428 may be formed on an underlying dielectric layer using a printing and/or coating technique. Each dielectric layer may include or be made of one or more high dielectric constant materials noted above and may be printed and/or coated on its underlying layer.
FIG. 5( a ) shows an MIM capacitor in examples consistent with the present invention. In this example, the structures 510 and 520 may include a carrier ( 512 or 522 ), a conductive layer ( 514 or 524 ) and a number of spots or other patterns ( 516 or 526 ) of a high-dielectric-constant material on the surface of the conductive layers ( 514 or 524 ). The spots may be formed by inkjet printing or other techniques. The spots may form any pattern or any combination of patterns and the pattern may be formed through the control of the formation process, such as an inkjet printing process. The structures 510 and 520 with spots may be pressed against the intermediate dielectric material 530 as shown in FIG. 5( b ). Where the spots 516 or 526 are formed from a dielectric material, these spots may protect the conductive layers 514 and 524 from metal-to-metal shorting. In addition, the dielectric constant for the capacitors 500 a and 500 b may depend on the distance between the neighboring spots.
FIG. 5( c ) shows another MIM capacitor in examples consistent with the present invention. Similar to FIG. 5( a ), the structures 510 and 520 may include a carrier ( 512 or 522 ), a conductive layer ( 514 or 524 ) and a number of spots ( 516 or 526 ) provided on the surface of the conductive layer ( 514 or 524 ) by inkjet printing or other techniques. The spots include dielectric spots ( 516 a or 526 a ) of a high dielectric constant material and conductive spots ( 516 b or 526 b ) of a conductive material. The structures 510 and 520 with the spots may then be pressed against an intermediate dielectric material 530 as shown in FIG. 5( d ). In one example, the dielectric spots 516 a and 526 a and the conductive spots 516 b and 526 b may form a crossed or checkered pattern. The conductive spots and dielectric spots, depending on the spot or pattern arrangements, may provide a capacitor with a wave-like dielectric layer formed by connecting the dielectric spots from the two structures, as shown in FIG. 5( e ). With the illustrated example, the capacitance depends on the minimum distance×between the two conductive spots as illustrated in FIG. 5( e ).
In another example, the spots or the dielectric layer may be formed by dielectric materials with different dielectric constants. FIG. 6( a ) shows the structure of the capacitors after lamination. Referring FIG. 6( a ), capacitor 600 a has a dielectric layer 630 having three different dielectric constants by having different dielectric materials or different combinations of dielectric materials. As a result, three capacitive elements in parallel are formed. Since these three capacitive elements share the conductive layers 614 and 624 , no additional wiring is required for connecting these capacitive elements in parallel. FIG. 6( b ) is an example of an equivalent electrical circuit of the structure of FIG. 6( a ). FIG. 6( c ) is the impedance curve of the capacitor of FIG. 6( a ), which shows a broader effective bandwidth than that of the SMD capacitors in parallel as shown in FIG. 6( d ).
Above discussion is directed to a single MIM capacitor. In some examples, a number of capacitive elements 710 a , 710 b , 710 c consistent with the present invention may form a set of capacitors 720 as shown in FIG. 7( a ). FIG. 7( b ) shows another exemplary set of MIM capacitors consistent with the present invention. FIG. 7( b ) includes capacitive elements 730 a and 730 b in parallel and a capacitive element 730 c . FIG. 7( c ) shows an exemplary set of MIM capacitors consistent with the present invention. FIG. 7( c ) includes capacitive elements 740 a , 740 b and 740 c . As shown in FIG. 7( c ), one of the electrodes of these three capacitors, such as the ground plane 750 , may be coupled together.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. | 4y
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FIELD OF THE INVENTION
This invention relates to a thermal transfer recording medium, particularly to a thermal transfer recording medium having an excellent fixing property without producing any voids and capable of speedily forming a high quality printed image with a high density and an excellent dot reproducibility even on a recording member having a low smoothness at a higher speed.
BACKGROUND OF THE INVENTION
The recording members on which images are printed with a thermal transfer recording medium are a smooth paper prepared especially for thermal transfer, PPC, a rough paper such as a bond paper, and an OHP sheet.
There are available conventional thermal transfer recording media capable of printing images with improved qualities and fixing properties on the above individual recording members of various types but, no recording media have so far been available which can print images with excellent qualities and fixing properties on any types of the recording members.
For example, conventional ink ribbon type thermal transfer recording media can provide good printed images on a smooth paper, while providing poor images on PPC and an OHP sheet, particularly inferior images on a rough paper.
There are proposed some thermal transfer recording media capable of providing high quality images on a rough paper, while they have another problem that dot reproducibility on a smooth paper and an OHP sheet is inferior.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a thermal transfer recording medium capable of providing a high quality printed image having an excellent fixing property and a high density without producing any voids even on recording members with low smoothness such as PPC, a rough paper and an OHP sheet as well as on a high smooth paper.
Another object of the invention is to provide a thermal transfer recording medium capable of providing a high quality image even at a high printing speed.
The above objects of the invention can be achieved by the thermal transfer recording medium comprising a support and provided thereon a thermosoftening layer, wherein at least one of the thermosoftening layers is provided on the support via an another layer and contains an olefin resin, a polyurethane resin and at least one of an acrylic resin and a polyester resin.
DETAILED DESCRIPTION OF THE INVENTION
Thermosoftening Layer
The thermosoftening layer provided on the support may be either of a single layer type or multilayer type. The multilayer preferably comprises two layers, an upper layer and a lower layer. Where the thermosoftening layer is of a single layer type, it is provided on a support via a peeling layer or an anchor layer.
It is important in the invention that a thermosoftening layer provided on a support via a different layer contains an olefin resin, a polyurethane resin and at least one of an acrylic resin and a polyester resin as the essential components.
The examples of the olefin resin are ethylene-vinyl acetate copolymer, ethylene-ethyl acryalate copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer, ethylene-vinyl acetate-maleic anhydride copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, polyethylene oxide, and ethylene-α olefin copolymer.
Among the above olefin resins, the ethylenic copolymers such as ethylene-vinyl acetate, ethylene-ethyl acrylate and ethylene-ethyl acrylate-maleic anhydride copolymers are preferably used.
The ethylenic copolymers have preferably the ethylene content of less than 72 wt %, more preferably less than 65 wt %.
The olefin resins may be used singly or in combination.
The examples of the acrylic resins are polyethyl methacrylate, polybutyl methacrylate, styrene-butyl acrylate copolymer, and butyl methacrylate-ethyl methacrylate copolymer.
The acrylic resins preferably have the molecular weight of not less than 150,000, more preferably not less than 200,000.
The acrylic resins may be used singly or in combination.
The polyester resins can be prepared by condensation polymerization of diols and dicarboxylic acids or by ring-opening polymerization of γ-caprolactone. The examples of the diols are ethylene glycol, propylene glycol, diethylene glycol, neopentyl glycol, polyethylene glycol, 1,4-butane diol, hexanediol, and bisphenol A. The examples of the dicarboxylic acids are adipic acid, azelaic acid, sebacic acid, maleic acid, isophthalic acid, and terephthalic acid.
The polyester resins may be used singly or in combination.
In the invention, at least one of the acrylic resin and the polyester resin is incorporated into the thermosoftening layer.
Generally, two types of the polyurethane resins are available; one is prepared from polyester polyol and diisocyanate, and the other from polyether polyol and diisocyanate. In the invention, preferred is the linear polyurethane resin prepared from polyester polyol and diisocyanate.
The polyester polyols for the above linear polyurethane resin can be prepared by condensation polymerization of diols and dicarboxylic acids. The examples of the diols are ethylene glycol, propylene glycol, butane diol, hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, polyethylene glycol, and bisphenol A and derivative thereof. The examples of the dicarboxylic acids are adipic acid, azelaic acid, sebacic acid, maleic acid, phthalic acid, isophthalic acid, and terephthalic acid.
The examples of the diisocyanates used for the above linear polyurethane resin are tolylene diisocynate, 4,4'-diphenylmethane diisocyanate, xylene diisocyanate, hexamethylene diisocyanate, 4,4'-methylene-bis(cyclohexyl isocyanate), and naphthylene diisocyanate.
The examples of the polyether polyols are polyethylene glycol and polypropylene glycol.
The ratios of the components constituting the linear polyurethane resin related to the invention are 1 to 30 mol %, preferably 3 to 25 mol % for diisocyanate, 30 to 60 mol %, preferably 35 to 55 mol % for diol, and 20 to 60 mol %, preferably 25 to 55 mol % for dicarboxylic acid.
The above linear polyurethane resin has the weight-average molecular weight of 10,000 to 100,000, preferably 15,000 to 80,000.
The glass transition point thereof ranges from -60 ° to 0° C., preferably -50° to 0° C., and the softening point ranges from 20° to 120° C., preferably 30° to 100° C.
The respective amounts of the above resins incorporated into the thermosoftening layer are 5 to 50 wt %, preferably 10 to 40 wt % for the olefin resin, 1 to 50 wt %, preferably 5 to 40 wt % for the acryl resin and/or polyester resin, and 0.1 to 30 wt %, preferably 0.2 to 20 wt % for the polyurethane resin, each based on the total amount of the above resins.
The other resins usable in combination with the above resins are rosin-modified resin, terpene resin, petroleum resin, styrene resin, styrene-acryl resin, ketone resin, maleic acid-modified resin, phenol resin, and terpene-phenol resin.
The softening point thereof is 50° to 150° C., preferably 70° to 125° C.
In the invention, the thermosoftening layer containing the resins related to the invention may or may not contain a colorant but, preferably contains it.
Where the thermosoftening layer containing the above resins contains a colorant, the other thermosoftening layers may not necessarily contain the colorant. Where no colorant is contained therein, the colorant is incorporated preferably into at least one of the other layers.
The colorants are inorganic and organic pigments and dyes.
The examples of the inorganic pigments are titanium dioxide, carbon black, zinc oxide, Prussian blue, cadmium sulfide, iron oxide, and chromates of lead, zinc, barium and calcium.
The examples of the organic pigments are the pigments of azo type, thioindigo type, anthraquinone type, anthanthrone type, and triphenedioxanzine type; vat-dye pigments; phthalocyanine pigments such as copper phthalocyanine and the derivatives thereof; and quinacridone pigments.
The examples of the dyes are acidic dye, direct dye, disperse dye, oil-soluble dye, and metal-containing oil-soluble dye.
The proportion of the colorant added to the thermosoftening layers is 1 to 30 wt %, preferably 5 to 25 wt %.
The thermosoftening layers other than the layer containing the resins related to the invention may be provided directly on the support or on the opposite side of the support.
The thermosoftening layer adjacent to the support may contain a fusible material and a thermoplastic resin in addition to the colorant.
The examples of the fusible materials are vegetable waxes such as carnauba wax, Japan wax, ouricury wax, and esparto wax; animal waxes such as bees wax, insect wax, shellac wax, and spermaceti; petroleum waxes such as paraffin wax, microcrystal wax, polyethylene wax, ester wax, and oxidation wax; and mineral waxes such as montan wax, ozokerite, and ceresin. In addition to the above waxes, there can be used as the fusible materials higher fatty acids such as palmitic acid, stearic acid, margaric acid, and behenic acid; higher alcohols such as palmityl alcohol, stearyl alcohol, behenyl alcohol, margaryl alcohol, myricyl alcohol, and eicosanol; higher fatty acid esters such as cetyl palmitate, myricyl palmitate, cetyl stearate, and myricyl stearate; amides such as acetamide, propionic amide, palmitic amide, stearic amide, and amide wax; and higher amines such as stearyl amine, behenyl amine, and palmityl amine.
Low molecular weight polymers can also be used as the fusible materials. The examples thereof are polystyrene, styrene-acrylic acid copolymers, polyester, rosin derivatives, petroleum resins, and ketone resins.
The waxes and low molecular weight polymers may be used singly or in combination.
The above fusible materials have preferably the melting point of 50° to 100° C.
The content of the fusible material is 10 to 90 wt %, preferably 20 to 80 wt %.
The above thermoplastic resins are exemplified by the foregoing olefin resins.
The content of the thermoplastic resin is 1 to 40 wt %, preferably 3 to 20 wt % and, more preferably 5 to 15 wt %.
Further, the thermosoftening layers may contain a surfactant, inorganic or organic fine particles such as metal powder and silica gel, and oil such as linseed oil and mineral oil.
Support
In the invention, the supports preferably have an excellent heat resistance and a high dimensional stability.
The raw materials of the supports are paper such as plain paper, condenser paper, laminated paper and coated paper; a resin film made of polyethylene, polyethylene terephthalate, polystyrene, polypropylene and polyimide; a composite material of paper and a resin film; and a metal sheet.
The thickness of the support is 30 μm or less, preferably 2 to 30 μm. The thickness exceeding 30 μm is liable to deteriorate thermal conductivity, which results in a lower printed image quality.
A backing layer may be provided on the back of the support.
Thermal Transfer Recording Medium
The thermosoftening layers can be coated on a support by hot-melt coating, aqueous coating or organic solvent coating.
In the thermosoftening layer consisting of the two layers, the thickness of the lower layer is 0.3 to 8.0 μm, preferably 0.5 to 6.0 μm, and that of the upper layer is 0.3 to 2.5 μm, preferably 0.5 to 2.0 μm.
There may be provided an interlayer between the above thermosoftening layers.
After coating each of the layers on the support, the resulting recording medium is subjected to drying and surface smoothing treatments and cut to a prescribed form such as a tape and a sheet, whereby the thermal transfer recording medium of the invention is prepared.
EXAMPLES
The invention is detailed with reference to the following examples and comparisons.
Example 1
The following components for the lower layer were coated on a 3.5 μm thick polyethylene terephthalate film to the dry thickness of 2.0 μm to thereby form the lower layer.
The coating was carried out by the hot melt method with a wire bar.
______________________________________Composition for the lower layer______________________________________Paraffin wax 70 wt %Ethylene-vinyl acetate copolymer 10 wt %Carbon black 15 wt %Dispersant 5 wt %______________________________________
Next, the following components for the upper layer, which were dispersed in methyl ethyl ketone, were coated on the lower layer to the dry thickness of 1.0 μm to form the upper layer, whereby the thermal transfer recording medium of the invention was prepared.
The coating was carried out with a wire bar.
______________________________________Composition for the upper layer______________________________________Ethylene-vinyl acetate copolymer 20 wt %[Ethylene/vinyl acetate = 59/41, MI: 65]Acrylic resin 10 wt %[Polypropyl methacrylate, MW: 190,000, Tg: 35° C.]Linear polyurethane resin 5 wt %4,4'-diphenylmethane diisocyanate/neopentylglycol/1,4-butane diol/adipic acid = 22/13/37/28,Tg: -20° C., Mw: 33,000]Alkyl phenol resin 50 wt %[Sp 80° C.]Carbon black 15 wt %______________________________________
Example 2
The thermal transfer recording medium of the invention was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Ethylene-vinyl acetate copolymer 10 wt %[Ethylene/vinyl acetate = 44/46]Polyester resin 20 wt %[Neopentyl glycol/cyclohexyl dimethanol/phthalic acid; Tg: 67° C., Mw: 20,000]Linear polyurethane resin 3 wt %[4,4'-diphenylmethane diisocyanate/1,4-butane diol/adipic acid = 14/49/37;Tg: -7.5° C., Mw: 39,000]Rosin-modified glycerol ester 47 wt %[Sp: 78° C.]Carbon black 20 wt %______________________________________
Example 3
The thermal transfer recording medium of the invention was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Ethylene-ethyl acrylate copolymer 20 wt %[Ethylene/ethyl acrylate = 65/35, MI: 25]Polybutyl methacrylate copolymer 30 wt %[Tg: 60° C., Mw: 35,000]Linear polyurethane resin 10 wt %[Tolylene diisocyanate/ethylene glycol/adipicacid = 5.5/49/45.5; Tg: -15° C., Mw: 35,000]Carnauba wax 20 wt %[Mp: 87° C.]Ketone resin 20 wt %[Sp: 90° C.]______________________________________
Example 4
The thermal transfer recording medium of the invention was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Ethylene-ethyl acrylate-maleic 10 wt %anhydride copolymer[Ethylene/ethyl acrylate/maleicanhydride = 69/29/2; MI: 7]Acrylic resin 20 wt %[Ethyl acrylate/methyl methacrylate/methacrylic acid; Tg: 35° C., Mw: 70,000]Polyester resin 10 wt %[Neopentyl glycol/cyclohexyl dimethanol/polycaprolactone/phthalic acid; Tg: 20° C.,Mw: 35,000]Polymethyl siloxane-modified urethane resin 5 wt %[Sp: 100° C., Mw: 46,000]Rosin-modified maleic acid resin 40 wt %[SP: 100° C.]Carbon black 15 wt %______________________________________
Example 5
The thermal transfer recording medium of the invention was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Ethylene-vinyl acetate copolymer 20 wt %[Ethylene/vinyl acetate = 30/70; MI: 45]Polybutyl methacrylate 10 wt %Tg: 20° C.; Mw: 360,000]Linear polyurethane resin 2 wt %Tolylene diisocyanate/1,4-butane diol/adipic acid = 5/50/45; Tg: -28° C.,Mw: 35,000]Rosin-modified synthetic resin 43 wt %[Sp: 100° C.]Carbon black 25 wt %______________________________________
Comparison 1
The comparative thermal transfer recording medium was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Polypropyl methacrylate 20 wt %[Mw: 190,000; Tg = 35° C.]Linear polyurethane resin 10 wt %[Tolylene diisocyanate/ethylene glycol/adipic acid = 5.5/49/45.5; Tg: -15° C.,Mw: 35,000]Alkyl phenol resin 50 wt %[Sp: 80° C.]Carbon black 20 wt %______________________________________
Comparison 2
The comparative thermal transfer recording medium was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Ethylene-vinyl acetate copolymer 10 wt %[Ethylene/vinyl acetate = 44/46; MI: 95]Linear polyurethane resin 20 wt %[4,4'-diphenylmethane diisocyanate/1,4-butane diol/adipic acid = 14/49/37;Tg: -7.5° C., Mw: 39,000]Alkyl phenol resin 70 wt %[Sp: 80° C.]______________________________________
Comparison 3
The comparative thermal transfer recording medium was prepared in the same manner as in Example 1, except that the components for the upper layer were replaced by the following ones.
______________________________________Composition for the upper layer______________________________________Ethylene-ethyl acrylate copolymer 20 wt %[Ethylene/ethyl acrylate = 65/35; MI: 25]Polyethylene terephthalate resin 20 wt %[Tg: 67° C.]Alkyl phenol resin 40 wt %[Sp: 80° C.]Carbon black 20 wt %______________________________________
Comparison 4
The comparative thermal transfer recording medium was prepared in the same manner as in Example 1, except that the lower layer was removed.
Evaluation
Each of the above thermal transfer recording media was loaded on a commercially available printer with a 24-dot serial head and an applied energy of 30 mJ/head, and was subjected to a printing test of alphabetical characters and 2-dot lines on a copy paper and a Lancaster paper (a Beck's smoothness: 2 seconds) to evaluate the high speed printing property on a rough paper in the following manner:
The printing was carried out with a platen pressure of the printer adjusted to 300 g/head at the printing speeds as shown in Table 1. The qualities of the printed images were visually observed and classified to the following three grades:
______________________________________Character◯ Excellent sharpness without voids and blurs.Δ Some voids observed.X Many voids observed on illegible letters.Line◯ Excellent printing without blurs and breaks.Δ Some blurs and breaks observed.X Inferior printing with no practicability.______________________________________
The results are shown in Table 1.
TABLE 1__________________________________________________________________________ Printing speed (cps) 20 30 Lancaster Lancaster Copy paper paper Copy paper paper Char- Char- Char- Char- ac- ac- ac- ac- ter Line ter Line ter Line ter Line__________________________________________________________________________Example 1 ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯Example 2 ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯Example 3 ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯Example 4 ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯Example 5 ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯Compar- ◯ Δ ◯ Δ ◯ Δ ◯ Xison 1Compar- ◯ Δ ◯ Δ ◯ Δ ◯ Xison 2Compar- ◯ ◯ Δ ◯ Δ ◯ X Δison 3Compar- X X X X X X X Xison 4__________________________________________________________________________
As is obvious from Table 1, the thermal transfer recording media of the invention have the excellent fixing properties even in a high speed printing on a variety of recording members without deteriorating the print quality.
Further, the recording media of the invention can provide the images with a high density and no voids even on a recording member having a smoothness as low as 1 to 2 seconds in terms of the Beck's smoothness. | 4y
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CROSS-NOTING TO RELATED APPLICATIONS
[0001] This application is a Continuation-In-Part application of application Ser. No. 10/642,920, filed on Aug. 18, 2003, which is a Continuation-In-Part application of application Ser. No. 09/856,196, filed on Sep. 4, 2001, which claims the benefit of PCT Application No. PCT/MX00/00034, filed Sep. 13, 2000, which claims the benefit of Mexican Application No. 998523, filed Sep. 17, 1999, the entire contents of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an absorbent composition of matter used to gradually release an active ingredient, such as a natural pesticide made from essential oils, for inhibiting the growth of bacteria, fungi and eradicating insect pests.
[0004] 2. Description of the Related Art
[0005] Commercially available insecticides, including those available for home use, commonly comprise active ingredients or “poisons” which are not only toxic to the target insect pests, but, if used in relatively confined environments and delivered as aerosol sprays, can be present in sufficient concentration to also be toxic to humans and household pets. Various undesirable side effects may include immediate or delayed neurotoxic reactions, and/or suffocation. Even the noxious odor of such materials can cause headaches or upset stomachs in some individuals. These adverse side effects are exacerbated when such compositions come in contact with persons of increased sensitivity, or persons of small body mass such as children or babies.
[0006] For some time, efforts have been made to develop insecticidal compositions, particularly those intended for residential use in aerosol form, which are effective in killing the targeted insect pests completely and quickly, but non-toxic to humans and pets. The Environmental Protection Agency (EPA) regulates the use of potentially toxic ingredients in pesticidal compositions under the Federal Insecticide, Fungicide and Rodenticide Act. Certain materials considered to be either active or inert materials by the EPA have been deregulated or otherwise identified as acceptable “safe” substances offering minimum risk in normal use. Other materials are currently undergoing investigation and may be deregulated in due course. Deregulated substances are generally considered non-poisonous by the consumer. Thus, the term “non-poisonous” as used herein is intended to convey a composition that, while highly effective in killing targeted insect pests, is safe to use around humans, particularly small children, and pets.
[0007] Unfortunately, non-poisonous insecticidal compositions available heretofore incorporating deregulated materials as the active ingredient have had limited efficacy. Attempts to use deregulated essential oils as the active ingredient in such insecticides, while having limited success, have generally been found to be either cost prohibitive, inadequately lethal to control a range of targeted insect pest species, or too slow-acting to enable the user to confirm that the insect has been killed and to dispose of the dead insect so as to avoid polluting the environment.
[0008] Many commercial products contain components which exercise a beneficial effect for only a limited time after introduction into their intended environment, being rapidly consumed, metabolized, vaporized or otherwise lost. To have continued effectiveness, such products must be reapplied at intervals, providing an undesirable and perhaps harmful excess at the times of reapplication and barely adequate levels at later times.
[0009] Microencapsulation techniques address the problem of controlled release by enclosing the transient component within hollow shells of differing size and wall thickness, which dissolve or otherwise rupture at different intervals to provide a more or less steady supply.
[0010] The temporary shells of microencapsulation can be replaced by more permanent semipermeable shells which allow escape through the shell wall without shell destruction, or the entire microcapsule replaced by a homogeneous semipermeable vehicle containing the active ingredient as a pure impregnant, solute or precipitate. In this latter process, the host vehicle serves not to enclose the active ingredient within a wall, but as a carrier from which it can only slowly escape by solution, diffusion, evaporation or some other rate-limited process. The utility of a particular host material as such a carrier depends on such properties as liquid content, pore size, compatibility with various environments, surface energy and wettability, susceptibility to post-impregnation modifications in properties, and ease of manufacture in suitable physical forms. The commercial exploitation of slow release carrier vehicles requires the availability of inert, microporous materials which are readily impregnable with a wide variety of substances, have controllable porosity, and possess acceptable physical properties.
[0011] Garlic ( Allium sativum Linn.) and/or its extract have been reported to have antibacterial and/or antifungal properties. It is known that Allicin isolated from the cloves of garlic had antibacterial properties against both Gram positive and Gram negative bacteria. Further, aqueous extracts of garlic have been reported to inhibit the growth of a variety of yeast-like fungi in the genera Candida, Cryptococcus, Rhudotoruto, Torulopsis and Trichosporon. It has also been previously reported that garlic extract and chips inhibit the growth of fungi such as Candida albicans, Aspergillus fumigatus and Aspergillus parasiticus. Because of its antifungal and antibacterial properties, garlic or its extract have been used as pesticides to control plant diseases such as mildew. It has also been used as an insecticide to control plant insects such as army worms, aphids and Colorado beetles. Most recently, garlic extract and water has been used to repel mosquitoes.
[0012] Therefore, there is a need in art for a safe, cost effective and highly efficient absorbent composition of matter that provides for a controlled time release of an aromatic substance, such as an essential oil or a combination of essential oils. One use of essential oils is to repel plagues of insects in the home as well as other agricultural crop damaging inserts.
SUMMARY OF THE INVENTION
[0013] The concept of the new product derived from the present invention, is enlarged in its range of applications. For example, uses in agriculture, home and industry are possible by combining its qualities to gradually release an aromatic substance to repel plagues of insects like cockroaches in kitchens or mosquitoes as well as other agricultural crop damaging insects. Good results are obtained by combining garlic or garlic extract, known for its qualities as a repellent for garden or agriculture damaging insects, and essential oils, such as eugenol, with this absorbent carrier.
[0014] Additionally, the absorbent carrier has the capacity to gradually release these forms of repellent aromas providing for a long lasting product; malodor, if present is also totally or partially absorbed. Inversely, attractant substances can be used, being of particularly useful application for household pets, for example, the use of an attractant aroma or fragrance in the production of cat litter. Additionally, the composition of matter in the present invention provides for a controlled time release of the different active ingredients, such as a natural pesticide, applied to the preferred embodiment (corn cob particles).
[0015] Essential Oil is defined as a subtle, volatile liquid obtained from plants and seeds or artificially obtained substitutes, for example, allyl isothiocyanate (AITC) as a substitute for mustard seed oil. Garlic or garlic extract is defined as any liquid removed from cloves of garlic and may therefore include garlic oil and water. Garlic extract has the same meaning as garlic juice.
[0016] In one aspect of the invention, an absorbent material comprises a carrier formed by particles obtained from one of a woody ring and a chaff ring of a corncob; and an active ingredient mixed with said carrier, wherein said active ingredient comprises an essential oil.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows the relationship between weed survival and application rate of a slow release formulation containing 85% garlic and 15% mustard oils in a microplot experiment with Impatiens.
[0018] FIG. 2 shows the relationship between nematode numbers and application rate of a slow-release formulation containing 85% garlic oil and 15% mustard oil in a microplot experiment with Impatiens.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] The preferred embodiment of the product object of the present invention consists of two basic elements: first, a carrier characterized by its great capacity for odor and malodor absorption, and gradual release of other active substances toward the air or surrounding atmosphere. Second, one or more chemical, natural or synthetic elements that added to the carrier complete diverse functions, according to the desired results (perfume surrounding air, react with undesirable substances present in the air, liberate therapeutic, repellent or attractant chemical agents).
[0020] The carrier which is the preferred embodiment of the product in the present invention is a material obtained from the threshed ear of corn ( Zea Maiz ) whose special physical and chemical qualities allow the previously described functions, of absorption and gradual release. To obtain the different components that comprise the threshed ear of corn, an industrial process, well known in the state of the art is required, which consists of separation, classification and sizing of each one of the components that constitute corncobs.
[0021] The threshed ear of the corn, also known as “olote” in Mexico, “spiga de maiz” in Castilian, corncob in English, “sabugo” in Portuguese and “balle de maïs” in French, if cut transversely is constituted by three concentric ring. Starting with the inner ring, they are known in English as pith, woody ring and chaff. The material of the present invention uses the woody ring and chaff portions.
[0022] The woody ring, as well as the chaff portion, has similar characteristics, both can be used as carriers for active ingredients as described in the body of the present invention. The main differences reside in the difference of absorption capacity and in the particle hardness. Other differences exist and are described below.
[0023] In order for the woody ring to comply with the requirements of the present invention it must have the following characteristics: woody ring should be 99% free of other cob particles, it should have no more than 1% dust or fines (the product should be air washed). By definition, fines are particles that can pass through U.S. standard screen size 400 (37 microns). It must be subjected to heat treatment that guarantees microbiology content and moisture levels under 10%. For correct functionality, the particle size should be uniform in size and ranges should not exceed a maximum of 3987 microns and a minimum of 42 microns.
[0024] The woody ring of corncobs is characterized by the following: a hardness of 4.5 on the Mohs scale, a fast absorbency of oil (for example soybean oil) of 1 to 1 on weight basis and the typical molecular structure of a natural fiber. Ideally particle sizing for the present invention should be between the following ranges: 1) retained or larger than a mesh of 3987 microns, 2) particles between 3987 and 1191 microns, 3) particles between 1191 and 841 microns, 4) particles between 841 and 42 microns.
[0025] The main characteristic of the particle size is the surface area that each one represents; for example, particles between 1410 and 841 microns have an average surface area of 5.88 square meters per gram. Particles between 841 and 420 microns have an average surface area of 7.20 square meters per gram. This characteristic is decisive in the qualities of absorption of different substances on the part of the carrier that embodies the product object of the present invention.
[0026] It is necessary to highlight that woody ring particles are characterized by having a structure that seen on an electron microscope resembles that of a sea sponge. One can infer that this type structure has capacity to admit and retain substances of small and large molecular size. This allows superior qualities of absorption in comparison to other products such as Cyclodextrin that as is known in the state of the art, only admits malodor molecules of small size.
[0027] The separate and classified sizes of woody ring have unique qualities for the absorption of scents from the air in contact with them. To illustrate this, diverse laboratory tests were made with surprising results as follows:
[0028] Example #1: A 100 gram portion of mature Camembert cheese, a 20 gram portion of bacon and a 10 cm dish containing 25 grams of woody ring particles sized between 1410 and 841 microns where all placed in a sealed glass container. Another glass container with the same components except for the woody ring particles was also prepared as a control sample. Both glass containers were inspected at intervals of 24 hs, 3 days, 5 days and 8 days; the container with the absorbent material practically didn't manifest the characteristic scent of the decomposition of products contained, while the control glass container presented potent and unpleasant scents.
[0029] Example #2: 10 grams of tobacco where incinerated in two sealed glass containers. One of the containers had a 10 cm diameter dish containing 10 grams of woody ring, sized between 1410 and 841 microns. The other container remained as a control sample. After 24 hours both containers where opened. The container with the absorbent woody ring particles did not present the characteristic scent of tobacco, while the control sample presented potent scents characteristic of tobacco smoke.
[0030] In both tests the evaluation of the scents or aromas were carried out by the authors of the present invention, as well as by a professional perfumist whose educated sense of the smell surrendered an objective opinion of these tests.
[0031] The characteristics of the Chaff portion of the corncob are similar to the woody ring portion in its ability to function as a carrier for fragrances and other active ingredients. The most distinguishing differences are: 1) more absorption; between 1.5 and 3 times it's weight in oil, 2) Particles size between 841 and 73 microns and 3) less particle flowability. Woody ring particles are rounder in shape than chaff and therefore flow better.
[0032] This physical difference between woody ring particles and chaff particles is translated into functional differences in the ability to absorb undesirable scents from the air. Additionally the granular form of the woody ring allows for more interparticle space for air-flow. While the smaller closer chaff particles allow less airflow.
[0033] Both woody ring and chaff are characterized by having an almost neutral pH, in the order of 6. This quality makes it an ideal inert carrier with all type of substances, since it does not react with active ingredients. Some other types of carriers have to be disactivated first to neutralize their pH content.
[0034] The physical and chemical characteristics of corncobs are not favorable for the development of microorganisms, therefore not providing fertile ground for bacteria or fungi that in turn cause malodor or disagreeable scents. It is known in the state of the art that a whole corncob can be stored without cover for periods of one year.
[0035] The functional differences of the woody ring portion (flowability and larger interparticle space) and that of the chaff (more absorption) allow for a great diversity of applications and use. These corncob fractions can be used combined or separately, for different applications, that are described for the absorbent carrier that integrates the product object of the present invention.
[0036] For example, if the functional objective, is the absorption of an active substance to be slowly released in the air and at the same time allowing the flow of malodor air to be absorbed, the suitable product is the one obtained from the woody ring. If on the contrary the functional object is to achieve absorption of an active substance to be slowly released in the air and the absorption of malodors or scents is not important, the elected product would be the chaff portion.
[0037] Other approaches to select the corncob fraction can be: the convenience of not having powders or fines. An example of such an application is the integration of the absorbent agent to active filtration systems where the use of the product from the woody ring is most suitable. If the active ingredient required is thick in nature or if product were required to be molded in a three-dimensional object (including the making of pellets), one would be inclined to select the chaff portion.
[0038] On the other hand, and a substantial element of the composition of matter, object of the present invention, are the active substances or ingredients to be used. These can be aromas, perfumes, flavors or other natural or chemical agents that are integrated to the product derived from the composition of matter object of the present invention. In general these substances are available in a liquid, powder or granular state and depending on the active agents chemical constitution, soluble in oil or water.
[0039] Under these conditions the absorbent carrier, depending on the type of active ingredients used, can absorb a larger or smaller quantity of said agent. This depends primarily on the size of the active ingredient molecule size, the absorbent carriers gradual release will also depend on this molecular size. The absorption of malodor or scents is simultaneously achieved. The intensity, duration and brightness of the aroma, with fragrances, will depend on factors of the active ingredient or agent's composition. For example, larger molecular size is equal to longer duration, while the presence of smaller molecular sizes such as those in an ester evaporate quickly.
[0040] Some examples for the formulation of the absorbent carrier with active substances in a liquid state are:
EXAMPLE #1
[0041] for fragrances, perfumes and therapeutic aromas, generally using a base of polyvinyl glycol, light mineral oil or microencapsulated powder or granular base, the concentration on a weight basis of the woody ring to active ingredient, is from 0.01% to 18%. A larger amount saturates the absorbent carrier and product flowability is greatly reduced. The concentration on a weight basis of the chaff portion to active ingredient is from 0.01% to 36%.
EXAMPLE #2
[0042] for repellents and attractants, generally in oleaginous or microencapsulated powder or granular bases such as Givaudans Flavor Burst™ products, the recommended concentration ranges, for the woody ring as well as the chaff portion, are similar to the previous example. Concentrations depend on the active ingredient or agent used and the functionality desired in the end product.
EXAMPLE #3
[0043] for oxidizers and chemical reducers or neutralizers, generally in a liquid or solid microencapsulated powder or granular base, the concentration ranges on a per weight basis, both for woody ring and chaff are from 0.05% to 5% of active ingredient or substance. Being that the determinant factor is not the capacity of carrier absorption, but rather the capacity to stay stable and not be affected by the active substance.
EXAMPLE #4
[0044] for antibacterial and fungicidal use, when these are in a water, oleaginous or microencapsulated powder or granular base, the proportion of active ingredient or agent on a per weight basis to absorbent carrier is the same as that of example #1. When the active ingredient uses a water base, the concentrations on a per weight basis can range from 0.01% to 25% with the woody ring fraction and 0.01% to 50% with chaff. The concentration to choose will be determined by the experience of whom ever prepares formulations according to the known state of the art.
[0045] Additionally as mentioned in previous examples, the formulation of the composition of matter or product object of the invention, can be made using liquid based active ingredients added to the absorbent carrier. The possibility also exists for the use of solid materials as active ingredients, usually in the form of pure or microencapsulated products. This variation allows more flexibility in the absorbent carriers applications. It can also take advantage of factors like stronger concentrations of active ingredients. Many pure substances come in solid form; the use of a liquid as diluent or dispersant of the pure substance implies a reduction in its concentration or strength. For example table salt NaCl is more intense to the palate than its version diluted in water, commonly called brine.
[0046] On the other hand the use of active ingredients in solid state can adhere and/or adsorb to the surface of the absorbent corn cob carrier, allowing it to use a larger proportion of it's inner absorbent capacity for malodor or other applications. The opposite occurs when using active ingredients in a liquid state, since these occupy more of the corncob carriers odor absorbent capacity thus partially reducing it's ability to absorb undesirable malodor.
[0047] The option of using active ingredients in solid state instead of liquid, is possible with the concurrence of 4 basic elements: an absorbent carrier, constituted by a fraction derived from corncobs, an active ingredient or agent that is in liquid or solid state; a combination resulting from the mix of a mineral or organic carrier with a liquid base active ingredient and finally, a substance that assures that, the active ingredients absorb or adsorb to the corncob carrier (avoiding the separation among carriers or agents and assuring correct homogeneity, functionality and dispersion).
[0048] To exemplify the above-mentioned we describe two practical examples. The results obtained, using two types of active ingredients one in liquid form and the other solid, both dispersed in the corncob carrier; woody ring sized between 1410 and 841 microns was used. The liquid active ingredient is a concentrated floral fragrance perfume using polyvinyl glycol as a carrier.
EXAMPLE #5
[0049] Corncob carrier mixed with an active ingredient in a liquid base. The density of the active ingredient determined a saturation point of 18% on a per weight basis to the corncob granules. 180 grams of active ingredient where mixed with a kilogram of corncob carrier. This proportion maintains carrier flowability, absorption of odors and slow release of active ingredient (fragrance).
[0050] Results: the perfuming active ingredient, was released gradually and perceived smell lasted 30 days. The corncob carrier continued absorbing scents in the air after 30 days.
EXAMPLE #6
[0051] two active ingredients; one utilizing an encapsulated active ingredient, commercially available, like Givaudan fragrance or flavor, in powder form and the other, using a laboratory sample, made by mixing Silicon Dioxide (SiO2), in proportion of 1 to 4 on the base of liquid active ingredient to Silicon Dioxide weight. The absorbent corncob carrier was impregnated with an adherent coating, in this case consisting of a 0.5% per weight basis, foamed solution of anionic surfactant with water. Once the corncob carrier was mixed with the foam, an adherent coating of foam formed on the corncob granules. Immediately after which the active ingredients in solid form where added. The active ingredient particles adhered to the coating and allowed for a homogeneous mixture without separation.
[0052] Results: In both cases the adhesion of solid particles to the corncob granules allowed a more intense and prolonged duration of the perfuming scent, which was slowly released over a 60 day period, in comparison to the 30 days obtained in example #5 with a liquid active ingredient perfume mixed directly with corncob granules. In both cases the corncob absorbed odors in the air even after 60 days.
[0053] Both examples, one with liquid and the other with solid active ingredients were performed at the same time. The new product was exposed to the air by placing it in a 40 cm by 5 cm dish. The product was placed in two separate rooms measuring 3×4×2.4 mts.
[0054] The adherents used to form a coating on corncob particles are within the following ranges:
EXAMPLE #7
[0055] Using surfactants as adherent coating: anionic, cationic and amphoteric can be used. The formulation is: foam obtained from adding water to 0.02% to 5% of surfactant by weight. The quantity of foam on a per weight basis to corncob woody ring fraction (carrier) is between 0.5% and 3.5%. Larger proportions do not allow for an appropriate mixture when adding active ingredients in solid form.
EXAMPLE #8
[0056] Using mineral oils as an adherent coating; they should be highly refined preferably odor and colorless; viscosity on the Saybolt scale (SUS/210 F) should be between 40 and 300. The concentration of mineral oil by weight to woody ring is between 0.5% and 18%.
EXAMPLE #9
[0057] for natural pesticides, generally using a base of essential oil or microencapsulated powder or granular base, the concentration on a weight basis of the woody ring to active ingredient, is from 0.01% to 18%. A larger amount saturates the absorbent carrier and product flowability is greatly reduced. The concentration on a weight basis of the chaff portion to active ingredient is from 0.01% to 36%.
[0058] Tests were conducted to determine the effectiveness of the absorbent composition used as a carrier for the active ingredient comprising an essential oil of the extract of garlic and/or allyl isothiocyanate (AITC) for the controlled release of the garlic extract against golden nematode in alpha potato. The treatment consisted of the application of 7 kg/hectare, 10 kg/hectare and 15 kg/hectare of the carrier and essential oil. The results indicate that the golden nematodes were greatly reduced as compared to a control, while productivity was greatly increased.
[0059] In another test, the effectiveness of the absorbent composition was used as a carrier for the essential oil of garlic and/or AITC for the controlled release of the garlic against Meloidogyne Incognita nematode. M. Incognita soil was obtained fro a farm in Mexico. The farmer had previously reported nematode infestation. The farmer mostly exports Tomato and other agricultural product to other countries. The carrier and garlic in the form of powder garlic was suspended in water at a concentration of 10.0 ml/l. The results indicated that the amount of larva of Meloidogyne Incongmita in 200 cc of soil was virtually eliminated. Further tests conducted in laboratories and greenhouses indicate similar results.
EXAMPLE #10
[0060] for nematicide/soil fumigants, generally in oleaginous or microencapsulated powder or granular bases, such as Givaudans ENROBED™ and FLAVORBURST™ products, the recommended concentration ranges, for the woody ring as well as the chaff portion, are similar to the previous example. Concentrations depend on the active ingredient or agent used and the functionality desired in the end product.
[0061] Experiment #1
[0062] The pesticidal activities of proprietary slow-release formulations of selected volatile compounds of plant origin were studied in greenhouse and microplot experiments. The selected volatile compounds were: natural thyme (20% oil) flavor; natural rosemary (20% oil) flavor; natural eugenol (20% oil) flavor; natural garlic (10% eugenol (20%); natural garlic (8.75%) eugenol (26.25%); artificial cinnamic aldehyde (20% oil) flavor; natural and artificial garlic (10%) cinnamic aldehyde (5%) flavor; natural and artificial garlic (10%) cinnamic aldehyde (10%) flavor; natural garlic (15% oil) flavor; natural and artificial garlic (12.75%) mustard (2.25%) flavor; natural and artificial garlic (85%) mustard seed (15% oil) flavor; and natural and artificial garlic (17%) mustard seed (3% oil). The compounds were encapsulated in micro-granules to form slow-release formulations. All these materials are used commonly in the food and perfume industries and are available from Givaudan of Switzerland.
[0063] In a greenhouse nematode experiment, the formulations were applied as a suspension (400 mgs granules/100 ml water) onto the soil surface of pots (10-cm diam, PVC) containing each 1 kg soil. The soil was a silt loam (pH 6.2; CEC <10 meq/100 g soil; org. matter <1.0%) from a cotton field infested with root-knot ( Meloidogyne incognita ), spiral ( Helicotylenchus dihystera ), and lesion ( Pratylenchus brachyurus ) nematodes as the main phytopathogenic species. Immediately after treatment each pot was covered with a clear 1.5 mil thick low density polyethylene bag held tight against the outer wall of the pot by a rubber band. Each treatment and control was represented by 7 replications (pots) arranged in a randomized complete block design on a greenhouse bench. Eight days after application, the bags were removed and soil samples (100 cm 3 ) were collected from each pot for nematological analysis (salad bowl incubation) and the pots were then planted with ‘Hutcheson’ soybean (5 seed/pot). After seven weeks the plants were removed from the pots, data on plant growth were recorded and final soil samples and roots were incubated to determine nematode numbers.
[0064] Soil and root populations of the root-knot nematode were significantly reduced by applications of thyme, rosemary and eugenol alone, and in combinations with garlic. Also, some combinations of garlic with mustard, notably the 85-15 ratio of garlic to mustard, were very active against the nematode while formulations with cinnamic aldehyde alone or with garlic were generally ineffective. Numbers of spiral nematodes in the roots were lowest in plants from pots treated with garlic-mustard combinations or with thyme. Rosemary treatments increased root populations of the lesion nematode while the other treatments had no effect on this nematode. Treatments without mustard resulted in the tallest plants with the heaviest roots and shoots. The inclusion of mustard in the formulations resulted in either no change in shoot height or in smaller increases in shoot and root weights when compared to the other formulations.
[0065] Experiment #2
[0066] The fungicidal action of the slow-release formulations used in Experiment #1 was assessed in an experiment with a sand-peat mix infested with a virulent isolate of Rhizoctonia solani obtained from diseased cotton seedlings. Application of slow release granules was by mixing directly with the sand-peat mix contained in pots (1 kg mix). The pots were covered with polyethylene bags and placed in a cool (20 C) room for 4 days when the bags were removed and 30 annual morningglory ( Ipomoea spp.) seed were spread on the sand-peat surface and then covered with a 1 cm thick layer of moist sand. The pots were placed back in the cool room for two days and were then transferred to a greenhouse bench. Statistical design was as described for the experiment with nematodes. The number of morningglory plants was determined at 10, 12, 14, and 17 days after application of the formulations. Following the last count the plants were separated from the sand-peat medium, and were washed and weighed. The condition of the root systems was assessed visually using a scale of 1-5 where 1 represented perfectly healthy roots and 5 roots with restricted root system with severe necrosis and lesions caused by the fungus. Efficacy was based on calculation of the area under the curve defining the number of morningglory plants per pot (Y axis) and days after treatment for the period between the 10 and 12 days after application (X axis).
[0067] R. solani eliminated over 70% of the possible morningglory plants. The disease was most successfully dealt with by formulations containing garlic oil. Least active compositions were those containing cinnamic aldehyde, rosemary, and thyme in increasing order of efficacy. Granules with eugenol were the most effective among the single component formulations. The most effective compound formulations were those containing garlic+eugenol 8.75-26.26% and garlic+mustard 12.75-2.25%; these formulations were the only ones with increased fungicidal activity over that obtained with garlic alone.
[0068] The herbicidal and nematicidal activities of a slow release formulation containing 15% mustard oil and 85% garlic oil was tested in a microplot (1 ft 2 ) experiment with soil infested with root-knot nematode ( M. incognita ) and a variety of annual weeds. The formulation was applied by drenching (1″ acre water) at rates 0-200 lbs a.i./A, followed by coverage of the plots with clear polyethylene (1 mil). After 10 days the plots were planted with 4-week old Impatiens seedlings. Weed control was directly proportional to the amount of active ingredient applied, as shown in FIG. 1 . Final populations of microbivorous nematodes were not affected by the treatments; however, root-knot juveniles were controlled or eliminated by rates ≧100 lbs ai/A, as shown in FIG. 2 . Decline in numbers of root-knot nematode juveniles in relation to rates was adequately described by exponential functions. Final populations of microbivorous nematodes were not affected by the treatments.
[0069] Data from the study suggested encapsulation may be useful for development of formulations with herbicidal, fungicidal and nematicidal activities based on natural compounds with high vapor pressures. In addition, a combination of garlic extract and essential oil has a synergistic effect that significantly increases the effectiveness of garlic and/or garlic extract alone. The ideal ratio of garlic to essential oil is 85% garlic to 15% essential oil, such as eugenol, mustard seed, or the like.
[0070] Finally active ingredients can be polymers, perfumes, oxidizers, attractants, repellents, reducers, antibacterials, etc, in solid form. These ingredients are mixed and dispersed with the granular corncob carrier sized between 42 and 3987 microns. The quantity of solid active ingredient dispersed should be between 0.01% and 40% per weight basis.
[0071] In conclusion, the incorporation of corncob fractions mentioned with active ingredients whether chemically synthesized or natural, improves the qualities and functionality that both elements have for themselves separately. However, the use of corncob fractions as absorbent of odoriferous substances from the environment is also a novel concept. The forms of carrying out the mixture or integration of these elements can vary according to the circumstance. The types of active ingredients that will be used depend on the functional objective that is pursued, equipment available and the experience of those skilled in the art.
[0072] While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit. | 4y
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CROSS REFERENCE
[0001] The present application is a non-provisional application claiming priority to U.S. Provisional Patent Application Ser. No. 61/316,777, filed Mar. 23, 2010, the disclosure of which is incorporated in its entirety herein by reference.
FIELD OF THE INVENTION
[0002] The present invention is directed to agriculture systems, more particularly to a self-contained semi automated production facility capable of culturing plants and other organisms in a controlled environment. The present invention is in no way limited to the examples disclosed herein.
BACKGROUND OF THE INVENTION
[0003] As population continues to grow, more land is required for habitation and more food is required for consumption. To accommodate growing urbanization and the decrease of arable land area, agricultural systems are centralizing to hotspots within the U.S. and other countries. However, these large-scale production systems may use inefficient methods, and some systems may select fruits and vegetables for their ability to be harvested early and transport for extended periods of time as opposed to being selected for good nutritional content. The increase use of transplants is needed to support the increase in farming for the rising population. Some consumers may wish to engage in supporting or growing locally produced foods for increased quality, nutrition and lower price. However, many cities lack the zoning laws to address small-scale agricultural operations. The present invention features a self-contained semi-automated production facility capable of culturing plants and other organisms in a controlled environment. The system of the present invention provides optimal environmental conditions, regardless of the external conditions, to allow for production of such plants and organisms. The system of the present invention helps to use better technologies to produce food, rather than the traditional methods. The present invention is in no way limited to the examples disclosed herein.
[0004] Any feature or combination of features described herein are included within the scope of the present invention provided that the features included in any such combination are not mutually inconsistent as will be apparent from the context, this specification, and the knowledge of one of ordinary skill in the art. Additional advantages and aspects of the present invention are apparent in the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a perspective view of an outer shell embodiment of the system of the present invention.
[0006] FIG. 2 is a top view of an outer shell embodiment of the system.
[0007] FIG. 3 is a front view of the system of FIG. 1 . User access points and alternative energy-generating components (e.g., Photovoltaic panels) are shown. Communication components are shown, which allow for communication of information to and from the device. The weather station shown communicates external environmental information to and from the device for control.
[0008] FIG. 4 is another perspective view of an embodiment of the system.
[0009] FIG. 5 is an exploded view of the interior shell of the system of the present invention, which slides into the exterior shell. The interior shell can help provide insulation, a chemical-resistant barrier, and beams for securing internal structural components, equipment, wiring, other devices, and the like. The chemical-resistant liner may allow for sterilization of the device without damaging the exterior shell.
[0010] FIG. 6 is a front exploded perspective view of the interior shell of the system.
[0011] FIG. 7 is a side exploded view of the interior shell system,
[0012] FIG. 8 is a top exploded view of the interior shell system.
[0013] FIG. 9 is a perspective internal view of the shell where the growing modules are inserted into the internal shell.
[0014] FIG. 10 is another perspective internal view of the shell where the growing modules are inserted into the internal shell.
[0015] FIG. 11 is another perspective internal view of the shell where the growing modules are inserted into the internal shell.
[0016] FIG. 12 is a front perspective internal view of the shell where the growing modules are inserted into the internal shell.
[0017] FIG. 13 is a top internal view of the shell where the growing modules are inserted into the internal shell.
[0018] FIG. 14 is a top perspective view of the components of the growing module.
[0019] FIG. 15 is a first perspective view of a growing module. The growing module may comprise a lighting component and a cultivation component, and the housing that surrounds it which holds the fans and part of the sliding mechanism. The removable and stackable modules are independently controlled and maintained in the system.
[0020] FIG. 16 is a second perspective view of the growing module of FIG. 16 . User access points, cultivation components, and ducting are shown.
[0021] FIG. 17 is a front perspective view of the growing module.
[0022] FIG. 18 is a top perspective view of the growing module.
[0023] FIG. 19 is another perspective view of the growing module.
[0024] FIG. 20 is another perspective view of the growing module.
[0025] FIG. 21 is a perspective view of the growing modules with alternate access doors/openings to the module.
[0026] FIG. 22 is another perspective view of the growing modules with alternate access doors/openings to the module.
[0027] FIG. 23 is a perspective view showing a growing module with front and back access doors.
[0028] FIG. 24 is a perspective view showing a growing module with a front only access door.
[0029] FIG. 25 is a perspective view showing a growing module with a side access door.
[0030] FIG. 26 is a perspective view showing a growing module with a top access door.
[0031] FIG. 27 is another perspective view showing a growing module with a top access door.
[0032] FIG. 28 is a perspective view of a growing plane in its structure.
[0033] FIG. 29 is a perspective view of a lighting and air flow unit with a growing plane.
[0034] FIG. 30 is another perspective view of a lighting and air flow unit with a growing plane.
[0035] FIG. 31 is a perspective view of a set of growing modules in a support frame.
[0036] FIG. 32 is another perspective view of a lighting and airflow unit with a growing plane.
[0037] FIG. 33 is an exploded perspective view of a lighting and airflow fixture of the light and airflow unit of the growing module. This lighting and airflow fixture can be used as the lighting unit within the growing module by itself or in combination with other lighting units.
[0038] FIG. 34 is another exploded view of a lighting and airflow fixture of the light and airflow unit of the growing module.
[0039] FIG. 35 is two exploded perspective views of a lighting and airflow fixture of the light and airflow unit of the growing module.
[0040] FIG. 36 is another exploded perspective view of a lighting and airflow fixture of the light and airflow unit of the growing module.
[0041] FIG. 37 is a perspective internal view of an alternate embodiment of the shell where the growing modules are inserted into the internal shell.
[0042] FIG. 38 is a perspective and internal view of an equipment module of the system of the present invention. The equipment module may support and contain hardware needed to operate the system. The equipment module may house lighting components, environmental control components, irrigation components, and the like.
[0043] FIG. 39 is another perspective and internal view of an equipment module of the system.
[0044] FIG. 40 is a front perspective and internal view of an equipment module of the system.
[0045] FIG. 41 is another front perspective view of an equipment module of the system.
[0046] FIG. 42 is a top view of an equipment module of the system.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0047] The following is a listing of numbers corresponding to a particular element referred to herein. The present invention is not limited to the described examples components and configurations:
[0048] 1. Growing plane(s)/flood tray(s) (pre-plumbed) (e.g., supporting aluminum structure)
[0049] 2. Fitted tray cover for growing plane
[0050] 3. Misting/aeroponic manifold (s)
[0051] 4. Sensor Array(s) inside growing area/volume (e.g., wireless, air T, RH, VPD, PAR, EC, pH, TDS, DO)
[0052] 5. Orifice for seedling/media placement
[0053] 6. Light Source(s) module(s) (T-8, T-12, T-5 Fluorescent; LED; HID; Incandescent; MV), LED-associated drivers
[0054] 7. Light Diffusing Panel(s) or colored lenses (plastic, glass, metal, composite, synthetic, etc.) with orifices or fixtures for airflow
[0055] 8. Air circulation fan(s) for lighting and airflow module(s)
[0056] 9. Growing Module (with light and airflow unit)
[0057] 10. Air circulation fans for growing area/volume
[0058] 11. Automatic/Controlled Louvre(s) (e.g., air ducting)
[0059] 12. Growing module container/box/skin
[0060] 13. Drawer/Shelving hardware to open and close and support growing plane/flood tray w/ products.
[0061] 14. Drawer/Shelving hardware to open, close, and support growing module.
[0062] 15. Handles to access growing module
[0063] 16. Handles to access contents of module
[0064] 17. Handles to extract products
[0065] 18. Environmental/A/C manifold to growing area
[0066] 19. Irrigation nutrient manifold to growing area
[0067] 20. HVAC Ducting
[0068] 21. Air ducting for A/C in
[0069] 22. Air ducting for A/C return
[0070] 23. Quick connect to irrigation in
[0071] 24. Quick connect to irrigation out/subsequent level
[0072] 25. Electrical plug to fans/light/sensors/electrical
[0073] 26. User Access Panel
[0074] 27. Cooling unit(s) (e.g. A/C)—ductless, split ductless, etc
[0075] 28. Waste heat fan for introduction into system for heating
[0076] 29. Exhaust system from equipment area (ballasts) (e.g., exhaust fan from electrical area×2)
[0077] 30. CO2 injection system (e.g., CO2 cylinder, regulator/actuator, comms, sensor)
[0078] 31. Air compressor(s)
[0079] 32. UV Sterilizing module(s) (e.g., sterilized unit that uses technologies such as UV, Ozone, chemicals, etc.)
[0080] 33. Injector Board(s) (e.g., injector(s), particulate filter(s), pressure gauge(s), inline sensor(s)—EC, pH—misc. fittings)
[0081] 34. Mixing tank(s)
[0082] 35. Stock Nutrient tank(s)
[0083] 36. Particulate filter(s)
[0084] 37. Inline sensor arrays (e.g., pH, EC, DO, T, TDS)
[0085] 38. Solenoids (e.g., fresh water, nutrient solution)
[0086] 39. Chiller(s) (e.g., inline, coil, flow thru)
[0087] 40. Heat Pump (e.g., coil, inline, drop in, flow thru)
[0088] 41. Fresh H2O riser
[0089] 42. Ballast(s) (e.g., fluorescent, HID, Or, power sources for LED)
[0090] 43. Interior cover/door (like a virus screen or pre entry—if box opened, contents still not exposed)
[0091] 44. Slide in chassis for support modules and equipment
[0092] 45. Support beams for anchoring
[0093] 46. Chemical resistant lining (e.g., Rhino Liner)
[0094] 47. Interior shell (insulation)
[0095] 48. Insulating paint
[0096] 49. Exterior shell
[0097] 50. Exterior Access Panel(s) or door
[0098] 51. Viewing window (glass, 2 way mirror, composite, plastic)
[0099] 52. Weather Station
[0100] 53. GPS Tracking and Communications components
[0101] 55. Controller/Computer control system (e.g., multiplexer, etc.)
[0102] 56. Photovoltaic System (e.g., wind turbine)
[0103] 56. Semi-automatic Crop Production System
[0104] 57. Visual detection system (camera, track, lenses (e.g., IR, UV, etc.)
[0105] Referring now to FIG. 1-42 , the present invention features a self-contained semi-automated production system 100 for culturing plants and other organisms in a controlled environment. The system 100 may be used in a variety of environments including but not limited to farms, yards, fields, warehouses or buildings, and the like. The system 100 can be easily transported from one location to another (e.g., because of the size of the system 100 and exterior shell 49 ). A user can engage in activities such as seeding and harvesting, and the system 100 of the present invention performs the necessary tasks for cultivating the plants or organisms. For example, the system 100 can control conditions including but not limited to light, temperature, relative humidity, carbon dioxide concentration, irrigation, and the like, via internal algorithms and programs. Without wishing to limit the present invention to any theory or mechanism, it is believed that the system 100 of the present invention is advantageous because little agricultural knowledge and experience is required of a user to grow plants and organisms with this system 100 . Also, since the system 100 is contained, production of plants, crops, and other organisms can occur continuously, independent of the external climate and conditions.
[0106] The system 100 of the present invention comprises an outer shell 49 . In some embodiments, the exterior shell 49 is similar to a shipping container, which is well known to one of ordinary skill in the art, however the exterior shell 49 is not limited to a shipping container. The exterior shell 49 may be constructed in a variety of sizes, for example sizes appropriate for small and large-scale use. An interior shell is disposed (e.g., slidably disposed) in the exterior shell 49 . As shown in FIG. 1 through FIG. 4 , the system 100 may comprise one or more power sources. The power source, for example, may comprise an alternative energy-generating component to create an off-grid or grid-tied system such as one or more photovoltaic panels 55 . One or more access points (e.g., doors 50 ) are disposed in the exterior shell 49 . The shell 49 may further comprise a variety of other components, for example for providing strength and/or insulation (e.g., for helping to control the internal environmental conditions accurately). As shown in FIG. 1 through FIG. 4 , insulating paint 48 may be coated on the exterior shell 49 . In some embodiments, the system 100 further comprises a weather station 52 , a GFS tracking and communications component 53 , and/or a computer control system 54 .
[0107] Referring now to FIG. 5 , the system 100 may comprise an interior shell 47 . The interior shell 47 may provide additional insulation for the system 100 (e.g., resistance to entry/exit or heating or cooling) and/or provide additional strength to the system 100 . A chemical-resistant liner 46 may be disposed in the interior shell 47 , allowing the unit to be effectively cleaned and sterilized in preparation for use or modification of the system without damaging the exterior shell 49 . Various attachment or fitting components 44 may be disposed on the outside of the interior shell 47 , allowing the interior shell 47 to be slid or mounted into the exterior shell 49 .
[0108] The interior shell 47 provides a means of mounting growing modules and other materials needed for the system 100 . For example, mounting components 45 may be disposed on the inner walls of the interior shell 47 for mounting growing modules, irrigation components, light components, and the like.
[0109] The present invention is not limited to a configuration with an exterior shell and an interior shell. For example, in some embodiments, the system 100 comprises a single shell, and in some embodiments, the system 100 comprises a plurality of shells.
[0110] The system 100 of the present invention comprises a plurality of growing modules, which are small isolated containment units. The system 100 creates micro-climates (e.g., with specific environmental parameters) inside the various growing modules (e.g., see FIG. 16 through FIG. 18 ) installed in the system 100 , and each growing module can be used to grow a specific plant or organism (or certain groups of plants or organisms), allowing the specific grown requirements of those plants or organisms to be met. The artificial micro-climates created allows for growth of these plants and organisms in non-traditional environments such as buildings and other urban settings. The growing modules allow for efficient control of parameters such as temperature, light, humidity, carbon dioxide concentration, and the like, because the growing modules have a small volume of space. The environmental parameters are also monitored via sensors 4 for feedback control.
[0111] The system 100 may also be designed to provide the user information about the plant or organism as it progresses, either for educational purposes or to help the user to make decisions, e.g., to modify conditions or to harvest, etc.
[0112] The ability to instantaneously adjust environmental settings based on what is occurring inside the growing area and regulates the immediate conditions of the aerial cultivation environment surrounding the organism, e.g., using components 10 , 27 , and 30 , allows for almost complete control of its culture and manipulation, modification, and/or response. Through the use of external weather stations (e.g., components 52 and 53 ), the system 100 may opt to utilize external conditions for heating and cooling the device, as well as using data for acclimatizing plants to external conditions where and when appropriate. Usage of passive cooling and heating will increase the efficiency of the device and lower its power requirements.
[0113] Using lighting sources in the growing module (e.g., component 9 ) such as, but not limited to solar collectors, LEDs, and fluorescent lights (e.g., components 6 , 7 , 8 , 42 ), the culture and manipulation of plants and other organisms is made possible without use of sunlight. And, such light sources allow the system 100 to manipulate the light conditions as desired (e.g., alternative light cycles, etc.). Light diffusing panels 7 may be used to achieve uniform lighting throughout the growing module, while able to provide cooling and additional airflow (possibly directed) to the aerial portion of the growing environment. Additional heat generated by the light source may be separated by the diffusing panel and then ventilated away from the growing environment (e.g., via component 8 ). Removing excess heat reduces the load on the air conditioning units, creating a more efficient system.
[0114] Controlling the light output reaching the organism allows precise and accurate control of the plant's/organism's development through exposure to specific wavelengths of light emitted including but not limited to UV, PAR, and IR spectrum. Since the amount of light needed varies per plant/organism, the system 100 of the present invention integrates algorithms contained within the computer control systems 54 . These algorithms and programs communicate with sensors 4 inside the growing modules to control light intensity, duration, color, quality, and other factors to yield the desired type of growth. This combination of automatic environmental control and sensing allows users to operate the device without prior knowledge of the plant's/organism's optimal conditions.
[0115] Computer control systems 54 coupled with sensors 4 (e.g., see components 30 , 33 , 37 , 52 , 53 , 55 , 57 , etc.) monitor real-time parameters including but not limited 10 : air temperature (AT), solution temperature, RH (%), PAR (umol m-2 s-1), CO2, dissolved oxygen, and other parameters, in addition to visual monitoring through camera and other imaging techniques. Communications between sensors and the computer control systems 54 allow for automated control of the conditions required for growth of the selected organism based on pre-programmed set points so the user requires no prior experience or knowledge. Alternatively, a user may enter alternate parameters or set points. Integrating visual monitoring allows for pre-programmed decision software to completely control plant growth and reduces the user's interaction. The computer and other control systems allow remote monitoring, access, and control to be accomplished through terminals, computers, laptops, PDA's, and other communication devices. Remote access allows user interaction and troubleshooting to occur in a non-contact manner, helping to eliminate disturbing of the production process.
[0116] The system 100 of the present invention integrates hydroponic methods on a controlled recirculating system and allows for high-efficiency usage of inputs such as water and fertilizer. Some examples of hydroponic methods (e.g., “deep-flow hydroponics”) have demonstrated reductions in water usage, for example by over about 50 fold. Recirculating methods increase the efficiency of water use by re-using treated water and preventing it from running out of the system and into the ground. Using an internal irrigation system (e.g., see components 19 , 23 , 31 , 33 - 40 ), water may be re-circulated continuously throughout the system. By treating with sterilizing lamps or anti-microbial lights and/or ozone-generating systems (e.g., see component 32 ), nutrient solution and water may be recirculated without introduction of pests, pathogens, and other organisms that may develop or be introduced otherwise. Other treatments (e.g., chemical additives) may be used with the system 100 of the present invention. The recirculation of nutrient solution and its sterilization using the system 100 may provide for optimal water usages and higher efficiency of usage for fertilizer as well.
[0117] The following the disclosures of the following U.S. patents are incorporated in their entirety by reference herein: U.S. Pat. No. 2008/10295400.
[0118] Various modifications of the invention, in addition to those described herein, will be apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims. Each reference cited in the present application is incorporated herein by reference in its entirety.
[0119] Although there has been shown and described the preferred embodiment of the present invention, it will be readily apparent to those skilled in the art that modifications may be made thereto which do not exceed the scope of the invention.
EXAMPLES
[0120] The examples provided below are merely examples to further clarify the present invention, and do not limit the scope of the invention in any way.
Example 1
Transplant Growing Protocol
Transplant Growing Protocol:
[0121] 1. Seed
[0122] 2. Germinate
[0123] 3. Preparation
[0124] 4. Transplant
[0125] 5. Monitor
[0126] 6. Harvest
[0127] 7. Adjust
1. Obtain clean materials needed for germination: Seed, substrate, tray & cover.
a. Use 98/200 cell Rockwool slabs and place inside black plastic germination tray.
i. (Optional) Rinse Rockwool substrate with water for 1 minute. ii. Use Jiffy preformed media and place in tray
b. Obtain the seed from the Seed Refrigerator.
2. Pour out the seed desired, and then seal the package and place back inside the refrigerator.
a. Be sure to place the seeds back into the refrigerator.
i. Thermal dormancy—High temperatures, above 18 C (optimal germination T) may have an adverse effect on lettuce seed germination. This can be reversed, however the cost and time to do so may be prohibitive. Instead, good seed management practices can prevent thermodormancy.
3. Pace seed in substrate.
a. Pelleted—Place 1 seed per cell in pre-stamped hole b. Naked—place 2-3 seeds in pre-stamped hole. c. (Optional) Smear one handful of vermiculite over the slab filling each hole lightly. Use more if necessary.
4. Place seeded trays in propagation area
a. If un-irrigated, place clear cover over tray. b. If irrigated, check irrigation settings and function
5. Check each day for germination and record %'s.
a. Ensure that the slab stay wet, but not soaking. b. Ensure no fungal growth or other
6. Begin irrigating with full strength nutrient solution 3 days after germination of at least 90% of the seeds. 7. 12 days after sowing, select plants that are uniform in size, shape, and leaf number as best as possible. 8. Check DFHS system settings to ensure set points are correct for crop.
a. EC˜2.0 mS/m; pH 5.90-6.10; DO˜6.9 ppm; H2O Temp˜21.0 C
9. Check tanks daily for EC/pH/DO and monitor accordingly. 10. Harvest plants
a. Remove dead leaves or unsightly parts of the product b. Store in humid, cool area out of direct sunlight
11. - - - 12. Weigh
a. A—Market acceptable; 150 g b. B—Not market acceptable, but still usable; 75 g-150 g c. C—Not usable, feed, compost or trash; <75 g
13. Grade
a. A—Market acceptable b. B—Not market acceptable, but still usable c. C—Not usable, feed, compost or trash
14. Sort 15. (Optional) Sterilize 16. Pack/Label 17. Storage
[0000]
Germ
Cult
Storage
Acclimatization
EC
Amb-<0.5
1.5
0
Ambient
pH
5.5-6.5
6
0
Ambient
Air T
29 C.
20-30
0-10
Ambient
Water T
20-30 C.
20-30
0
Ambient
RH
50-99%
10-99%
10-99%
Ambient
VPD
Ambient
PAR
0-250
250-1000
0-250
Ambient
CO2
300-1000 ppm
300-2000
0-500
Ambient
Air
0-.5 m/s
0-5 m/s
0-5
Ambient
Speed | 4y
|
[0001] The invention concerns a rolling bearing particularly a turbocharger rolling bearing, comprising a shaft comprising a first, radial elevation and a second, radial elevation and a first, inner ring which can be fixed to the shaft, said first inner ring comprising at least one first radially outer rolling element raceway for rolling elements to roll on, a first, radial narrowing and a second, radial narrowing, the first, radial elevation and the first, radial narrowing being provided for forming a first press fit, and, respectively, the second, radial elevation and the second, radial narrowing being provided for forming a second press fit.
BACKGROUND
[0002] DE 10 2008 020 067 A1 discloses a turbocharger bearing which comprises a shaft comprising different outer diameters onto which shaft the one-piece inner ring is pushed. Axially on the outer side, the inner ring is seated on the shaft through a press fit, while, centrally, under the inner ring is situated a smaller outer diameter without press fit so that a low frictional force is produced during pressing in.
SUMMARY OF THE INVENTION
[0003] The problem of this construction is that a rolling bearing comprising a two-piece inner ring cannot be adequately centered on a shaft of this type because the inner rings, or the inner ring parts, are seated only on axially outer sides on the shaft. However, at high speeds of rotation, it is exactly an optimal centering that is of vital importance for the life duration of the rolling bearing.
[0004] It is an object of the present invention to provide a shaft permitting an optimized press-in force for rolling bearings comprising two inner rings, which shaft also enables the required centering.
[0005] The present invention provides a rolling bearing of the initially described type by the fact that the shaft comprises a third, radial elevation and a fourth, radial elevation, and a second inner ring that can be fixed to the shaft comprises at least one second, radially outer rolling element raceway for the rolling elements to roll on, a third, radial narrowing and a fourth, radial narrowing, the third, radial elevation and the third, radial narrowing being provided for forming a third press fit, and, respectively, the fourth, radial elevation and the fourth, radial narrowing being provided for forming a fourth press fit.
[0006] By press fit is to be understood a radial interference fit in which the inner diameter of a hollow cylindrical part is substantially equal to or smaller than the associated outer diameter of the pressed-in cylindrical part. In no case may a lash freedom be formed or positioning steps be permitted that allow a non-concentric arrangement of the respect inner ring relative to the shaft. For example, not even a negative lash in the range of less than 5 micrometers, particularly, 1 or 2 micrometers, may be tolerated between the narrowing and the corresponding elevation for achieving a reliable centering. Although this type of fit is occasionally called a transition fit, it is also to be understood as a press fit in the following. The pressed-in cylindrical part in the sense of the present invention is the first, second, third or fourth elevation of the shaft, and the hollow cylindrical part is the first, second, third or fourth radial narrowing of one of the inner rings.
[0007] The radial narrowings are arranged on the inner side of the inner rings and are configured on these. Therefore, they are narrowings that are situated radially on the inside.
[0008] Altogether, four press fits are implemented, each inner ring comprising two press fits on which the respective inner ring is supported.
[0009] It is also possible to provide a temporary press fit during assembly. A temporary press fit is created if two neighboring radial narrowings have the same diameter. In this case, during assembly, that is to say, when the shaft is being inserted into the inner rings, one of the radial elevations must be pushed through the temporary press fit of a radial narrowing to then form a permanent (and thus operable) press fit with a neighboring radial narrowing.
[0010] According to the invention, the lever action between the two press fits of the respective the inner ring effects the centering of the inner rings on the shaft required for the operation of the rolling bearing. This is possible because one of the two press fits serves as a fulcrum and the other as an actuator of the lever.
[0011] Advantageously, the first outer diameter of the first, radial elevation is smaller than or equal to the second outer diameter of the second, radial elevation, the second outer diameter of the second, radial elevation is smaller than or equal to the third outer diameter of the third, radial elevation and the third outer diameter of the third, radial elevation is smaller than or equal to the fourth outer diameter of the fourth, radial elevation. The dimension of the outer diameters can be varied depending on the case of use.
[0012] If temporary press fits are to be avoided, it is purposeful to provide an ascending sequence of outer diameters for the radial elevations that get smaller in insertion direction, i.e. in this case, the first radial elevation, with the smallest outer diameter, is inserted at first.
[0013] According to the invention, the first and the third press fit form a fulcrum before the second and the fourth press fit, respectively, are formed. During the formation of the second and fourth press fit respectively, the inner ring concerned is oriented such that it is arranged concentric to the shaft. This is accomplished with a low force because the lever arms between the first and the second press fit, as also between the third and the fourth press fit, can be chosen to be long enough to enable any radial positioning still required at the second and, respectively, the fourth press fit.
[0014] It is further purposeful to center the second inner ring later in time than the first inner ring. During the centering step, the lever arm of the respective inner ring works against the frictional force that is produced on a contact surface to the next-situated component. If the second inner ring were centered at first, frictional forces would be created on both sides of the first inner ring, that is to say, also in direction towards the second inner ring.
[0015] It is particularly preferred to realize the first press fit as a fulcrum for the first inner ring. Following this, the second press fit of the first inner ring is made in order to arrange the first inner ring concentrically to the shaft through a radial correction at the second press fit. The third press fit then likewise takes over the function of a fulcrum so that it can be used in the then following realization of the fourth press fit as a fulcrum during the radial orientation.
[0016] Advantageously, the first outer diameter and the second outer diameter are equal to each other. This simplifies the production of the first inner ring. The first inner ring is at first centered i.e. it is brought into as concentric a position as possible to the shaft in that the second press fit is situated on that axial side of the first inner ring on which the shaft is inserted at first.
[0017] Advantageously, the third outer diameter and the fourth outer diameter are equal to each other. This simplifies the production of the second inner ring in a corresponding manner.
[0018] In an advantageous form of embodiment, the shaft has a multi-piece configuration in the region of the press fits. For instance, it is not necessary to make the shaft with all its elevations by turning out of one work piece. Instead, it is possible to fix rings on the shaft that form the radial elevations.
[0019] Preferably, the shaft merges, in the region of the first, second, third and/or fourth radial elevation, beginning from the first, second, third and/or, respectively, fourth outer diameter, in one axial direction, with a linear, concave or convex shape into a further region with a further outer diameter, the further outer diameter being respectively smaller than the first, second, third and fourth outer diameter. This thread-in aid assists in the insertion of the shaft during assembly so that the press-in force required is reduced further. Thus, the outer region of the shaft that carries the respective linear, concave or convex transition separates the elevations from the non-carrying outer regions. An outer region in this case can be, for example, a cylindrical outer surface of the shaft.
[0020] The simplest manner of configuring the transitions is to make them as linear assembly inclinations which preferably form an angle of between 5 and 30 degrees to the axis of rotation, ideally 15 or 25 degrees. In this way, the axial force of the shaft to be inserted can be converted easily into a small radial force for correction of positions.
[0021] Preferably, the respective first or second inner ring merges in the region of the first, second, third and/or fourth radial narrowing, beginning from the first, second, third and, respectively, fourth inner diameter, in one axial direction, with a linear, concave or convex shape into a region with a further inner diameter that is respectively larger than the first, second, third and fourth inner diameter. Thus, the respective linear, concave or convex transition separates an outer region that carries the respective inner ring from a non-carrying outer region of the shaft.
[0022] In the case of these transitions, too, the simplest manner of configuring them is to make them as linear assembly inclinations which preferably form an angle of between 5 and 30 degrees to the axis of rotation, ideally 15 or 25 degrees.
[0023] Advantageously, a first axial distance of the first press fit from the second press fit is larger than half the axial width of the first inner ring and/or a second axial distance of the third press fit from the fourth press fit is larger than half the axial width of the second inner ring. In this way, the respective lever arm between the press fits is enlarged and the press-in force is reduced still further.
[0024] Advantageously, the second press fit is arranged on one axial end of the first inner ring and/or the third press fit is arranged on one end of the second inner ring.
[0025] In one advantageous form of embodiment, the shaft can be inserted into the inner rings, arranged axially relative to each other, till one axial front end of the second inner ring comes to abut against a turbine-side axial stop and thus signalizes the operable position of the shaft within the inner rings. In this way, the installer can be sure that, when the two surfaces contact each other, all the press fits required for centering have been completed and the centering of the two rings has been terminated.
[0026] Further advantageous embodiments and preferred further developments of the invention can be seen in the description of the figures and/or in the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The invention will be described and explained more closely in the following with reference to the examples of embodiment illustrated in the figures.
[0028] FIG. 1 shows a turbocharger rolling bearing in a section taken along the shaft, in ready-assembled, operative state,
[0029] FIG. 2 shows the turbocharger rolling bearing of FIG. 1 , during a first assembly step,
[0030] FIG. 3 shows the turbocharger rolling bearing of FIG. 1 , during a second assembly step,
[0031] FIG. 4 shows the turbocharger rolling bearing of FIG. 1 , during a third assembly step,
[0032] FIG. 5 shows the turbocharger rolling bearing of FIG. 1 , during a fourth assembly step,
[0033] FIG. 6 shows the turbocharger rolling bearing of FIG. 1 , during a fifth assembly step,
[0034] FIG. 7 shows the turbocharger rolling bearing of FIG. 1 , during a sixth assembly step, and
[0035] FIG. 8 shows a schematic press-in force diagram for a conventional turbocharger bearing compared to the turbocharger bearing of FIG. 1 .
DETAILED DESCRIPTION
[0036] FIG. 1 shows a turbocharger rolling bearing in a section taken along the shaft in an operative state after installation.
[0037] The fractional part of the shaft 19 which is surrounded by both the inner rings 17 , 18 merges on a turbine-side into the turbine-side end ET which is either itself a part of the turbocharger turbine or is configured to be connected to this. On the opposite end of the fractional part of the shaft 19 , the fractional part merges with the compressor-side end EK of the fractional part which can be a part of the compressor or be capable of being connected to this. The compressor (not illustrated) has the function of compressing the air sucked in by the piston of an engine. The energy required for this is delivered by a turbine (likewise not illustrated) which is driven in a hot housing by the exhaust gas stream and is transferred via the shaft 19 and also via the fractional part thereof in the turbocharger bearing.
[0038] The fractional part comprises, in alternating order, from the compressor-side end EK to the turbine-side end ET, non-contacting regions and radial elevations in the following sequence: non contacting region 9 , first radial elevation 5 , non-contacting region 10 , second radial elevation 6 , third radial elevation 7 , non-contacting region 11 , fourth radial elevation 8 and non-contacting region 12 .
[0039] All the transitions are radially convex in shape and serve as assembly inclinations that form an angle of less than 30 degrees relative to the axis of rotation. This applies both to the transition between the first and the second radial elevation 6 , 7 and to the transitions between a non-contacting region 9 , 10 , 11 , 12 and the respective neighboring radial elevation 1 , 2 , 3 , 4 .
[0040] In this way, the first elevation 5 and the radial narrowing 1 form the first operative press fit exactly as also the second elevation 6 and the second narrowing 2 form the second press fit. Both press fits again form the base for the first inner ring 17 and assure its radial centering for an operation at very high speeds of rotation without any detrimental effect on the rolling elements 21 during their rolling motion in their raceways around the inner ring 17 so that they can no longer trigger a disturbing vibration. Analogously, this also applies to the inner ring 18 that is centered through the third and the fourth press fits.
[0041] The centering of the shaft 19 is realized during installation by the fact that the compressor-side end EK is inserted through the second inner ring 18 and then further through the first inner ring 17 . During this step, it is also possible for the temporary press fits to be formed before the operative position of the shaft 19 in the inner rings 17 , 18 is reached. The further the first press fit is arranged from the second press fit, respectively, the third press fit from the fourth press fit, the larger is the lever arm during radial centering so that centering can be effected with the lowest possible force. The length of the first lever arm T 1 is smaller than the axial width B 1 of the first inner ring 17 . In most cases, however, a shorter length is required to enable a passing-by of the temporary press fits one after the other during installation, that is to say, to make it possible to pass by as few as possible at the same time. This applies analogously to the length T 2 of the second lever arm between the third and the fourth press fit of the second inner ring 18 . In any case, it is still purposeful to provide at least one lever arm with a length of at least half the width of the respective inner ring 17 , 18 :
[0000] T 1>½* B 1; T 2> V 2* B 2;
[0042] In the example of embodiment of FIG. 1 , the third and the fourth press fits are situated radially further outwards than the first and the second press fits. In particular, the first and the second radial narrowings 1 , 2 even have the same inner radius and, respectively, the first and the second radial elevations 5 , 6 have the same outer radius. Analogously, this also applies to the radial narrowings 3 , 4 and the radial elevations 7 , 8 but, respectively, with larger same inner radii and larger and larger same outer radii.
[0043] In this way, only two temporary press fits get formed during assembly of the shaft 19 , viz. when the first radial elevation 5 passes the second radial narrowing 2 and when the third radial elevation 7 passes the radial narrowing 3 .
[0044] The assembly with the two temporary press fits is illustrated in the following FIGS. 2 to 7 which show the turbocharger rolling bearing of FIG. 1 in six different assembly steps.
[0045] FIGS. 2 to 7 show the turbocharger rolling bearing of FIG. 1 in the assembly steps one to six.
[0046] In the first assembly step of FIG. 2 , the shaft 19 was pushed in between the first radial elevation 5 and the second radial narrowing 2 up to the incipient first temporary press fit 20 . The press-in force is further enhanced through the second temporary press fit 30 that gets formed between the third radial elevation 7 and the fourth radial narrowing, i.e. exists partially simultaneously with the first press fit, as shown in FIG. 3 .
[0047] In the following FIGS. 4 to 7 , further incipient press fits, 40 , 50 , 60 and 70 are shown which, however, are intended to become permanent i.e. they are provided for the operation of the rolling bearing as soon as the axial front end surface S of the second inner ring comes to abut against the axial surface A.
[0048] The length L of the fractional part of the shaft 19 between the two ends EK and ET is equal to the sum of the inner ring widths B 1 , B 2 because the two inner rings 17 , 18 abut against each other at the axial stop 72 .
[0049] Alternatively, the press fits can have the same dimensions i.e. the radial narrowings and the radial elevations possess the same inner radii and the same outer radii. In addition, it is also possible that all radial narrowings and also all radial elevations have different inner radii and different outer radii, so that no temporary press fits but only permanent press fits are formed.
[0050] FIG. 8 shows a schematic press-in force diagram for a conventional turbocharger bearing compared to the turbocharger bearing of FIG. 1 .
[0051] The curve G 1 has a linear dependence on the press-in length that is plotted against the length from 0 to L of the fractional part of the shaft 19 . The hatched area under the straight line G 1 corresponds to the press-in energy for a conventional cylindrical shaft which is pressed into a hollow cylindrical interior with axially non-variable respective inner and outer radii.
[0052] The curve G 2 shows schematically the course of the press-in force as a function of the press-in length, which force rises shortly after L/2, at the first temporary press fit, to F 1 , to then rise further immediately thereafter by reason of the second temporary press fit to F 2 .
[0053] For instance it can be assumed by approximation that the temporary press fits produce the same press-in force FO. Thus, the following applies:
[0000] F 1= F 0; F 2=2* F 0; F 3=3* F 0; F 4=4* F 0;
[0054] Further, by idealization, it is assumed for the sake of illustration, that the areas of the press fits approximate zero. A small press fit length results in a low press-in force. In practice, however, these will always form surface contacts which, in the graphical illustration of the curve G 2 , form linearly ascending or, respectively, declining flanks. Idealized, these result in vertical flanks.
[0055] The curve G 2 is divided into two sections. The smaller one represents the temporary press fits G 20 and G 30 which have to be overcome together with the press-in force FE=F 2 ; in the case of the temporary press fit G 20 , the press-in force FE=F 1 suffices. The hatched area situated under the curve G 2 corresponds to the energy which has to be provided for overcoming the temporary press fits G 20 and G 30 .
[0056] At the end of the press-in path are situated, at short intervals, the operative, permanent press fits, i.e. their beginnings G 40 , G 50 , G 60 and G 70 that have to be overcome. For this purpose, the press-in force increases stepwise from FE=0 to FE=F 4 . On the whole, the press-in energy of the curve G 2 is clearly lower compared to the press-in energy of the curve G 1 because the integral over the press-in length from 0 to L of G 2 turns out to be clearly higher.
[0057] The permanent press fit 40 is the first operative press fit and the permanent press fit 50 is the second operative press fit.
[0058] To summarize, the invention concerns a rolling bearing particularly a turbocharger rolling bearing, comprising a shaft comprising a first, radial elevation and a second, radial elevation and a first inner ring which can be fixed to the shaft, said first inner ring comprising at least one first radially outer rolling element raceway for the rolling elements to roll on, a first, radial narrowing and a second, radial narrowing, the first, radial elevation and the first, radial narrowing being provided for forming a first press fit, and, respectively, the second, radial elevation and the second, radial narrowing being provided for forming a second press fit. The aim of the invention is to provide a rolling bearing with an optimized press-in force for high speeds of rotation which also enables a simple centering of two inner rings. For this purpose, the shaft comprises a third, radial elevation and a fourth, radial elevation, and a second inner ring that can be fixed to the shaft comprises at least one second, radially outer rolling element raceway for the rolling elements to roll on, a third, radial narrowing and a fourth, radial narrowing, the third, radial elevation and the third, radial narrowing being provided for forming a third press fit, and, respectively, the fourth, radial elevation and the fourth, radial narrowing being provided for forming a fourth press fit.
[0000]
List of reference numerals
A
Axial stop
B1
Axial width
B2
Axial width
ET
Turbine-side end
EK
Compressor-side end
G1
First curve
G2
Second curve
G20
Beginning of temporary
press fit
G30
Beginning of temporary press fit
G40
Beginning of permanent
press fit
G50
Beginning of permanent press fit
G60
Beginning of temporary
press fit
G70
Beginning of temporary press fit
F1
Single press-in force
F2
Double press-in force
F3
Triple press-in force
F4
Quadruple press-in force
FE
Press-in force
L
Length of fractional part of shaft
S
Axial front end
T1
Axial press fit spacing
T2
Axial press fit spacing
1
First radial narrowing
2
Second radial narrowing
3
Third radial narrowing
4
Fourth radial narrowing
5
First radial elevation
6
Second radial elevation
7
Third radial elevation
8
Fourth radial elevation
9
Non-contacting region
10
Non-contacting region
11
Non-contacting region
12
Non-contacting region
13
Non-narrowed region
14
Non-narrowed region
15
Non-narrowed region
16
Non-narrowed region
17
First inner ring
18
Second inner ring
19
Shaft
20
Temporary press fit
21
Rolling element
30
Temporary press fit
40
Operative press fit
50
Operative press fit
51
Progressive operative press fit
60
Operative press fit
70
Operative press fit Operative
71
Progressive operative
press fit
press fit
72
Axial stop | 4y
|
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to a test piece for use in DNA analysis, immunological analysis, and the like, and a system for reading out image information from the test piece.
Description of the Related Art
Recently, genetic engineering has exhibited rapid progress, and the human genome project for decoding the base sequence of human genomes which amount to 100,000 in number is progressing.
Further, enzyme immunoassay, fluorescent antibody technique and the like utilizing antigen-antibody reactions have been used in diagnoses and studies, and studies for searching DNAs which affect genetic diseases are now progressing. In such a situation, a microarray technique is now attracting attention.
In the microarray technique, a microarray chip (sometimes called a DNA chip) comprising a plurality of known cDNAs (an example of specific binding substances) coated in a matrix on a substrate such as a membrane filter or a slide glass at a high density (at intervals of not larger than several hundred μm) is used and DNAs (an example of organism-originating substances) taken from cells of a normal person A and labeled with a fluorescent dye a and DNAs taken from cells of a genetic-diseased person B and labeled with a fluorescent dye b are dropped onto the microarray chip by pipettes or the like, thereby hybridizing the DNAs of the specimens with the cDNAs on the microarray chip. Thereafter, exciting light beams which respectively excite the fluorescent dyes a and b are projected onto the cDNAs by causing the exciting light beams to scan the microarray chip and fluorescence emitted from each other of the cDNAs is detected by a photodetector. Then the cDNAs with which the DNAs of each specimen are hybridized are determined on the basis of the result of the detection, and the cDNAs with which the DNAs of the normal person A are hybridized and those with which the DNAs of the diseased person B are hybridized are compared, whereby DNAs expressed or lost by genetic disease can be determined.
In the microarray technique, it is necessary to precisely two-dimensionally scan the microarray chip coated with cDNAs at a high density, and there has been proposed a radiation image read-out apparatus with such a precise scanning system. See, for instance, Japanese Unexamined Patent Publication No. 10(1998)-3134.
The kinds of cDNAs to be used sometimes amount to several tens of thousands and in such a case, the cDNAs must be coated on a plurality of substrates. However when the number of the microarray chips to be used increases, replacement of microarray chips becomes troublesome.
SUMMARY OF THE INVENTION
In view of the foregoing observations and description, the primary object of the present invention is to provide a test piece on which an increased number of specific binding substances such as cDNAs can be disposed, and a system for reading out image information from the test piece.
In accordance with one aspect of the present invention, there is provided a test piece such as a microarray chip for use in biological analyses comprising a plurality of different known specific binding substances such as cDNAs disposed in predetermined positions on a substrate such as a slide glass, wherein the improvement comprises that
the specific binding substances are disposed on a plurality of surfaces provided by the substrate and arranged in the direction of thickness of the substrate.
The plurality of surfaces provided by the substrate and arranged in the direction of thickness of the substrate may be opposite sides of the substrate or may be provided by a multi-layered substrate formed by a plurality of substrates which are stacked and bonded together so that the surfaces on which the specific binding substances are disposed are substantially in parallel to each other.
It is preferred that the specific binding substances be disposed on the surfaces in positions where the specific binding substances on the respective surfaces do not interfere with each other in the direction of thickness of the substrate, that is, the specific binding substances on the respective surfaces do not overlap with each other in the direction of thickness of the substrate.
The substrate may be formed of any material so long as the specific binding substances can be spotted and stably held on the substrate and the substrate is optically transparent to the exciting light and the fluorescence emitted from the specific binding substances upon exposure to the exciting light. For example, the substrate may be a membrane filter or a slide glass. Further the substrate may be subjected to pretreatment so that the specific binding substances are stably held on the substrate.
The specific binding substances include hormones, tumor markers, enzymes, antibodies, antigens, abzymes, other proteins, nucleic acids, cDNAs, DNAs, RNAs, and the like, and means those which can be specifically bound with an organism-originating substance. The means of the expression “known” differs by the specific binding substance. For example, when the specific binding substance is a nucleic acid, “known” means that the base sequence, the lengths of the bases and the like are known, and when specific binding substance is protein, “known ” means that the composition of the amino acid is known. The specific binding substances are disposed by one kind for each position.
In accordance with another aspect of the present invention, there is provided a system for reading out image information from the test piece of the present invention comprising
a test piece holder portion which holds a test piece of the present invention the specific binding substances on which have been hybridized with an organism-originating substance labeled with fluorescent dye,
an exciting light source which emits exciting light for exciting the fluorescent dye,
a photoelectric read-out means which photoelectrically reads out fluorescence emitted from the fluorescent dye upon exposure to the exciting light,
a scanning means which has an optical head for projecting the exciting light onto the test piece and leading fluorescence, which is emitted from the fluorescent dye and travels through the surface of the test piece onto which the exciting light is projected, to the photoelectric read-out means, and causes the exciting light to scan the test piece, and
a controller which controls the exciting light source, the photoelectric read-out means and the scanning means so that fluorescence emitted from the specific binding substances upon exposure to the exciting light is detected for each of the surfaces of the test piece.
The test piece holder portion may comprise a table on which the test piece is placed. In this case, the test piece is placed on the table with its one side in contact with the table, and accordingly, it is necessary that the table is transparent to at least the fluorescence. When the test piece holder portion is in the form of a member which supports only the four corners of the test piece, the test piece holder portion need not be transparent.
The organism-originating substance may be a wide variety of substances originated from an organism including hormones, tumor markers, enzymes, proteins, antibodies, various substances which can be antigens, nucleic acids, cDNAs, mRNAs and the like.
The exciting light is light suitable for exciting the fluorescent dye including a laser beam.
As the photoelectric read-out means, a photomultiplier which can detect at a high sensitivity weak light such as fluorescence may be suitably used. However, various known photoelectric read-out means such as a cooled CCD may be used without limited to the photomultiplier.
In accordance with the present invention, since the specific binding substances are disposed on a plurality of surfaces provided by the substrate and arranged in the direction of thickness of the substrate, an increased number of specific binding substances can be disposed on one test piece and accordingly, the number of test pieces to be used can be less even if a large number of specific binding substances are used, whereby the frequency at which the test pieces are replaced can be reduced and reading operation can be effectively performed.
When the specific binding substances are disposed on opposite sides of a single substrate, the test piece can be manufactured at low cost.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a test piece in accordance with a first embodiment of the present invention,
FIG. 2 is a cross-sectional view taken along line I—I in FIG. 1,
FIG. 3 is a cross-sectional view of a test piece in accordance with a second embodiment of the present invention,
FIG. 4A is a perspective view of an image information read-out system in accordance with a third embodiment of the present invention,
FIG. 4B is a schematic side view of the image information read-out system,
FIG. 5 is a view for illustrating the operation of the image information read-out system of the third embodiment,
FIG. 6A is a perspective view of an image information read-out system in accordance with a fourth embodiment of the present invention, and
FIG. 6B is a schematic side view of the image information read-out system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIGS. 1 and 2, a test piece 1 in accordance with a first embodiment of the present invention comprises a substrate 2 which is a slide glass in this particular embodiment, and a plurality of different cDNAs disposed in a plurality of positions on opposite sides (upper and lower sides) of the substrate 2 . The base sequences of the cDNAs are known and correspond to different DNAs. The kind of each cDNA and the position of each cDNA are predetermined.
As shown in FIG. 2, the cDNAs on the upper side of the substrate 2 and those on the lower side of the substrate 2 are positioned not to overlap each other in the direction of thickness of the substrate 2 . Further the upper and lower sides of the substrate 2 have been subjected to surface treatment so that the cDNAs are bonded to the surfaces and accordingly, the cDNAs on the lower side of the substrate 2 cannot peel off the substrate 2 . The thickness of the substrate 2 is about 1 mm, and each of the cDNAs is disposed on the surface of the substrate 2 in a spot of a diameter 30 to 100 μm with the spot intervals of about 300 μm.
FIG. 3 shows a test piece in accordance with a second embodiment of the present invention. The test piece shown in FIG. 3 is provided with a substrate formed of a pair of substrate segments 2 A and 2 B which are bonded together with a spacer 3 interposed therebetween. The cDNAs are disposed on the upper surfaces of the respective substrate segments 2 A and 2 B not to overlap each other in the direction of thickness of the substrate segments 2 A and 2 B. The spacer 3 may either be discontinuous or continuous over the entire periphery of the substrate segments 2 A and 2 B.
FIGS. 4A and 4B show an image information read-out system in accordance with a third embodiment of the present convention for reading out image information from the test piece 1 shown in FIG. 1 . The image information read-out system comprises a transparent sample table 20 on which the test piece 1 , having applied with an organism-originating substance labeled with a fluorescent dye, is supported at its four corners, a laser 30 which emits a laser beam L in a wavelength band exciting the fluorescent dye, a lens 31 which converges the laser beam L as emitted from the laser 30 into a thin laser beam, a photomultiplier 40 which photoelectrically detects fluorescence K 1 and K 2 emitted from the cDNAs upon exposure to the laser beam L (K 1 represents the fluorescence emitted from the cDNAs on the upper surface of the substrate 2 and K 2 represents the fluorescence emitted from the cDNAs on the lower surface of the substrate 2 ), an optical head 50 which causes the laser beam L to impinge upon the test piece 1 on the sample table 20 and leads the fluorescence K 1 or K 2 to the photomultiplier 40 , a laser beam cut filter 41 disposed on the optical path between the optical head 50 and the photomultiplier 40 , a condenser lens 55 which is disposed between the test piece 1 and the photomultiplier 40 and forms a confocal optical system together with a lens 53 , an aperture plate 56 which has an aperture 56 a which permits to impinge upon the lens 41 only light from a portion of the test piece 1 on which the laser beam L is converged by the lens 53 , a main scanning system 60 which moves the optical head 50 in the direction of arrow X at a constant speed, a sub-scanning means 80 which moves the laser 30 , the optical head 50 , the condenser lens 55 , the aperture plate 56 , the laser beam cut filter 41 and the photomultiplier 40 in the direction of arrow Y (perpendicular to the direction of arrow X) integrally with each other, a logarithmic amplifier 42 which logarithmically amplifies a detecting signal output from the photomultiplier 40 , and an A/D converter 43 which digitizes the amplified detecting signal.
The laser 30 is arranged to emits the laser beam L in the direction of arrow X, and the photomultiplier 40 is arranged to detect the fluorescence K 1 or K 2 impinging thereupon in the direction of arrow X.
The optical head 50 comprises a plane mirror 51 which reflects the thin laser beam L, traveling in the direction of arrow X, in a direction perpendicular to the surfaces of the test piece 1 , a mirror 52 which is provided with an aperture 52 a through which the laser beam L reflected by the plane mirror 51 impinges upon the test piece 1 and reflects the major parts of the fluorescence K 1 or K 2 , emitted downward from the lower surface of the test piece 1 , to impinge upon the photomultiplier 40 , and the lens 53 which collimates the fluorescence K 1 or K 2 which emits downward from the test piece 1 as divergent light. The plane mirror 51 , the mirror 52 with the aperture 52 a and the lens 53 are integrated into a unit. The lens 53 is movable in the direction of thickness of the test piece 1 or in the direction of arrow Z to move a focal point of the lens 53 selectively to the upper surface of the substrate 2 and to the lower surface of the same. When the fluorescence K 1 from the upper surface of the test piece 1 is to be detected, the focal point of the lens 53 is moved to the upper surface of the test piece 1 and when the fluorescence K 2 from the lower surface of the test piece 1 is to be detected, the focal point of the lens 53 is moved to the lower surface of the test piece 1 , whereby the florescence K 1 and K 2 can be collimated to beams of substantially the same diameters.
The laser beam cut filter 41 is a filter which transmits the fluorescence K 1 and K 2 but does not transmit the laser beam L so that a part of the laser beam L scattered by the test piece 1 , the sample table 20 and the like cannot impinge upon the photomultiplier 40 .
Operation of the image information read-out system of this embodiment will be described, hereinbelow.
The position of the lens 53 is first adjusted so that the focal point of the lens 53 is on the upper surface of the substrate 2 . Then the main scanning means 60 moves the optical head 50 at a constant high speed in the direction of arrow X. At each moment during movement of the optical head 50 , the laser 30 emits a laser beam L in the direction of arrow X and the lens 31 converges the laser beam L into a thin laser beam. The thin laser beam L enters the optical head 50 . The laser beam L is then reflected upward by the plane mirror 51 and impinges upon a fine area on the upper surface of the test piece 1 through the aperture 52 a of the mirror 52 and the lens 53 .
When an organism-originating substance labeled with fluorescent dye exists in the fine area exposed to the laser beam L, the fluorescent dye is excited by the laser beam L and emits fluorescence K 1 .
The fluorescence K 1 spread around the area and the part of the fluorescence K 1 traveling downward from the lower surface of the test piece 1 is collimated by the lens 53 of the optical head 50 into a substantially parallel downward beam and impinges upon the mirror 52 . Though the part of the fluorescence K 1 impinges upon the aperture 52 a travels further downward through the aperture 52 a (the diameter of the aperture 52 a is sufficiently small as compared with the beam diameter), the major part of the fluorescence K 1 is reflected by the mirror 52 to travel in the direction of arrow X and to impinge upon the photomultiplier 40 through the condenser lens 55 , the aperture 56 a of the aperture plate 56 and the laser bean cut filter 41 .
Though a part of the laser beam L impinging upon the test piece 1 is scattered by the test piece 1 , the sample table 20 and the like and travels toward the photomultiplier 40 , it is prevented from impinging upon the photomultiplier 40 by the laser beam cut filter 41 . Further since the test piece 1 and the photomultiplier 40 are optically connected by a confocal optical system, fluorescence from a part of the test piece other than the part exposed to the laser beam L is prevented from impinging upon the photomultiplier 40 and blur of a fluoresce image obtained can be avoided even if the area exposed to the laser beam L is shifted or enlarged.
The fluorescence K 1 impinging upon the photomultiplier 40 is photoelectrically detected by the photomultiplier 40 and read out as an electric signal. The electric signal is amplified by the amplifier 42 and is converted to a digital signal by the A/D converter 43 .
During these steps, the optical head 50 is kept moved in the direction of arrow X by the main scanning system 60 , and a digital signal is output from the A/D converter 43 for each main scanning position on the test piece 1 .
Each time the main scanning along one line is ended, the sub-scanning means 80 slightly moves the laser 30 , the optical head 50 , the laser beam cut filter 41 and the photomultiplier 40 in the direction of arrow Y (sub-scanning) and the main scanning is repeated. The sub-scanning may be effected in parallel to the main scanning.
Thus the entire area of the upper surface of the test piece 1 is two-dimensionally scanned by the laser beam L, and image information representing the distribution of the organism-originating substances labeled by the fluorescent dye on the upper surface of the substrate 2 is obtained.
Thereafter the optical head 50 is returned to the initial position by the main scanning means 60 and the sub-scanning means 80 . Then the lens 53 is moved downward by d 0 (FIG. 5) so that the focal point of the lens 53 is on the lower surface of the substrate 2 . Then the fluorescence K 2 emitted from the lower surface of the test piece 1 is detected and converted to a digital signal in the same manner as described above and image information representing the distribution of the organism-originating substances labeled by the fluorescent dye on the lower surface of the substrate 2 is obtained.
The image information representing the distribution of the organism-originating substances labeled by the fluorescent dye on the upper and lower surfaces of the substrate 2 is displayed on a monitor (not shown).
Thus in the image information read-out system of this embodiment, image information can be read out from opposite sides of the test piece 1 of the first embodiment of the present invention, where cDNAs are disposed on opposite sides of the substrate 2 .
The image information read-out system of this embodiment can be used to read out image information from the test piece of the second embodiment of the present invention shown in FIG. 3 . In this case, the lens 53 is moved so that the focal point of the lens 53 is selectively moved to the upper surface of the substrate segment 2 A and that of the substrate segment 2 B.
Though, in the embodiment described above, the fluorescence K 1 emitted from the cDNAs on the upper surface of the substrate 2 and the fluorescence K 2 emitted from the cDNAs on the lower surface of the substrate 2 are separately detected by moving the focal point of the lens 53 forming a confocal optical system, it is possible to separately detect the fluorescence K 1 and the fluorescence K 2 by moving the aperture plate 56 along the optical axis with the lens 53 kept stationary. That is, when the laser beam L is projected onto the test piece 1 with the focal point of the lens 53 set at the middle between the upper and lower surfaces of the substrate 2 , the fluorescence K 1 is emitted from the cDNAs on the upper surface of the substrate 2 and the fluorescence K 2 is emitted from the cDNAs on the lower surface of the substrate 2 . Depending on the position of the aperture plate 56 along the optical axis, only one of the fluorescence K 1 and the fluorescence K 2 can pass through the aperture 56 a in the aperture plate 56 .
FIGS. 6A and 6B show an image information read-out system in accordance with a fourth embodiment of the present invention for reading out image information from the test piece 1 shown in FIG. 1 . The image information read-out system of this embodiment comprises a sample table 20 , a first laser 30 A, a first lens 31 A, a first photomultiplier 40 A, an optical head 50 , a first laser beam cut filter 41 A, a first condenser lens 55 A, a first aperture plate 56 A, a main scanning system 60 , a sub-scanning means 80 , a first logarithmic amplifier 42 A, and a first A/D converter 43 A, which are basically the same as the sample table 20 , the laser 30 , the lens 31 , the photomultiplier 40 , the optical head 50 , the laser beam cut filter 41 , the condenser lens 55 , the aperture plate 56 , the main scanning system 60 , the sub-scanning means 80 , the logarithmic amplifier 42 , and the A/D converter 43 employed in the third embodiment. The image information read-out system of this embodiment further comprises a second laser 30 B, a second lens 31 B, a second condenser lens 55 B, a second aperture plate 56 B, a second laser beam cut filter 41 B, a second photomultiplier 40 B, a second logarithmic amplifier 42 B, a second A/D converter 43 B, a polarization beam splitter 62 which transmits the laser beam L 1 emitted from the first laser 30 A and reflects the laser beam L 2 emitted from the second laser 30 B, and a half-silvered mirror 63 which transmits a part of the fluorescence K 1 and the fluorescence K 2 to impinge upon the first photomultiplier 40 A, and reflects the other part of the fluorescence K 1 and the fluorescence K 2 to impinge upon the second photomultiplier 40 B.
The first and second lenses 31 A and 31 B are identical to each other. The first and second lasers 30 A and 30 B are basically identical to each other except that the laser beam LI emitted from the first laser 30 A is polarized in the vertical direction as seen in FIG. 6 B and the laser beam L 2 emitted from the second laser 30 B is polarized in a direction perpendicular to the surface of the paper on which FIG. 6B is drawn. With this arrangement, the laser beam L 1 transmits the polarization beam splitter 62 and the laser beam L 2 is reflected by the same.
The distance d 2 between the beam radiating end of the 16 second laser 30 B and the second lens 31 B is set larger than the distance d 1 between the beam radiating end of the first laser 30 A and the first lens 31 A so that the diameter of the laser beam L 1 on the upper surface of the substrate 2 becomes equal to the diameter of the laser beam L 2 on the lower surface of the substrate 2 .
Further, the distance D 2 between the second condenser lens 55 B and the second aperture plate 56 B is set larger than the distance D 1 between the first condenser lens 55 A and the first aperture plate 56 A. In the fourth embodiment, the leaser beams L 1 and L 2 are simultaneously emitted from the first and second lasers 30 A and 30 B, and the fluorescence K 1 and the fluorescence K 2 emitted respectively from the upper and lower surfaces of the test piece 1 are simultaneously detected. The fluorescence K 1 and the fluorescence K 2 emitted respectively from the upper and lower surfaces of the test piece 1 simultaneously travel in the direction of arrow X. The fluorescence K 1 and the fluorescence K 2 emitted respectively from the upper and lower surfaces of the test piece 1 are separated by the half-silvered mirror 63 to parts which respectively travel to the first and second photomultipliers 40 A and 401 B. Either of the parts includes both the fluorescence K 1 and the fluorescence K 2 , and accordingly, the distance D 2 between the second condenser lens 55 B and the second aperture plate 56 B is set larger than the distance D 1 between the first condenser lens 55 A and the first aperture plate 56 so that only the fluorescence K 1 can pass through the aperture of the first aperture plate 56 A and only the fluorescence K 2 can pass through the aperture of the second aperture plate 56 B, whereby the fluorescence K 1 and the fluorescence K 2 are separately detected by the photomultipliers 40 A and 40 B, respectively.
Operation of the image information read-out system of this embodiment will be described, hereinbelow.
When the laser beams L 1 and L 2 are projected onto the upper and lower surfaces of the test piece 1 , fluorescence K 1 and fluorescence K 2 are emitted from the upper and lower surfaces of the test piece 1 , respectively, and simultaneously travel in the direction of arrow X as a light bundle. The light bundle is divided into two light bundles by the half-silvered mirror 63 , one traveling toward the first photomultiplier 40 A and the other traveling toward the second photomultiplier 40 B. The fluorescence K 1 included in said one light bundle impinges upon the first photomultiplier 40 A through the first condenser lens 55 A, the first aperture plate 56 A and the first laser beam cut filter 41 A and is detected by the first photomultiplier 40 A, whereas the fluorescence K 2 included in said the other light bundle impinges upon the second photomultiplier 40 B through the second condenser lens 55 B, the second aperture plate 56 B and the second laser beam cut filter 41 B and is detected by the second photomultiplier 40 B.
The fluorescence K 1 and the fluorescence K 2 are photoelectrically converted to electric signals respectively by the first and second photomultipliers 40 A and 40 B, and the electric signals are amplified by the first and second amplifiers 42 A and 42 B and then digitized by the first and second A/D converters 43 A and 43 B. Then visible images are displayed on a monitor (not shown) on the basis of the digitized electric signals.
Thus also in the image information read-out system of this embodiment, image information can be read out from opposite sides of the test piece 1 of the first embodiment of the present invention, where cDNAs are disposed on opposite sides of the substrate 2 .
The image information read-out system of this embodiment can be used to read out image information from the test piece of the second embodiment of the present invention shown in FIG. 3 . In this case, positions of the first and second lenses 31 A and 31 B and the first and second aperture plates 56 A and 56 B are adjusted to read out image information from the substrate segments 2 A and 2 B.
Though, in the embodiments described above, the CDNAs are disposed not to overlap each other in the direction of thickness of the substrate 2 or the substrate segments 2 A and 2 B, they may overlap each other in the direction of thickness of the substrate 2 or the substrate segments 2 A and 2 B when the image information read-out system comprises a confocal optical system. | 4y
|
CLAIM OF PRIORITY
[0001] This application claims priority under 35 USC §119(e) to U.S. Patent Application Ser. No. 61/884,956, filed on Sep. 30, 2013, the entire contents of which are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The invention relates to blood compatible surfaces, e.g., blood compatible surfaces formed of nanoparticles.
BACKGROUND OF THE INVENTION
[0003] Medical devices, such as hemodialysis membranes, artificial blood vessels, heart valves, biosensors, vascular stents, and other medical devices are often used for the treatment of various medical conditions. However, when foreign objects such as medical devices come into contact with the blood of a patient, a series of adverse biological reactions can be triggered, including thrombosis, inflammation, and fibrosis. These reactions can be harmful to the patient and can cause failure of the implanted medical device.
[0004] To limit these adverse biological reactions, blood compatible materials can be used for such medical devices. Blood compatible materials limit the activation of the blood coagulation system and reduce or prevent platelet adhesion to the material. Surface treatments can be applied to medical devices to improve the blood compatibility of the devices. For instance, self-assembled monolayers, polyethylene oxide, heparin, zwitterionic polymers, and inorganic coatings such as diamond can be applied to the surface of medical devices.
SUMMARY OF THE INVENTION
[0005] The invention is based, at least in part, on the discovery that high curvature surfaces, such as coatings formed of nanoparticles having a diameter less than about 100 nm, exhibit blood compatible properties. For instance, high curvature blood compatible surfaces, such as coatings formed of nanoparticles, limit the intrinsic coagulation activity of blood in the vicinity of the blood compatible surface. Furthermore, high curvature blood compatible surfaces limit the adsorption of platelets onto the surface. In some cases, when medical devices come into contact with the blood of a patient, adverse biological reactions, such as blood coagulation on surfaces of the medical device and platelet adhesion to the device, can occur. By covering medical devices with high curvature blood compatible surfaces, such adverse biological reactions can be mitigated.
[0006] In a general aspect, methods of making blood compatible articles as described herein include providing a substrate; and forming a rough surface on the substrate. The rough surface includes a plurality of three-dimensionally curved features each having a radius of curvature of less than about 50 nm, e.g., 5, 10, 15, 20, 25, 30, 35, 40, or 45 nm. The surface includes a sufficient concentration of features per unit area to limit blood coagulation activity on the substrate and to limit the number of platelets that adhere to the surface when the substrate is exposed to blood.
[0007] Embodiments can include one or more of the following features. The three-dimensionally curved features can be substantially hemispherical. The rough surface can include a coating on the substrate, and the coating can include the features. The features can include nanoparticles and the fill rate of the nanoparticles in the coating can be at least about 50%, e.g., at least about 60% or at least about 70%. The features can be nanoparticles having a diameter of less than about 100 nm. The diameter of the nanoparticles can be less than about 85 nm, e.g., between about 12 nm and about 85 nm, e.g., 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, or 80 nm. The diameter of the nanoparticles can be the average particle size of the nanoparticles as determined by a dynamic light scattering method. For example, the nanoparticles can include one or more of ceramic nanoparticles, metal nanoparticles, metal oxide nanoparticles, and polymer nanoparticles.
[0008] Forming the coatings can include spin coating the nanoparticles onto the surface of the substrate, e.g., of a medical device or blood container. Spin coating the nanoparticles can include spin coating a suspension of nanoparticles in an alcohol, such as ethanol. Forming the coating can include annealing the spin coated nanoparticles, e.g., once they are adhered to the substrate. Forming the coating can include one or more of dip coating the nanoparticles onto the surface of the substrate, spray coating the nanoparticles onto the surface, precipitating the nanoparticles onto the surface, and depositing the nanoparticles by flame spray pyrolysis. Forming the coating can include forming the features by nano-imprinting on the substrate. The features also can be formed of a biocompatible material.
[0009] The substrate can be a medical device or part of a medical device, such as an implantable medical device, e.g., a surgical device, an implantable device, a blood pump, a blood container, or a conduit for blood transport. The medical device can be configured for exposure to blood outside of the body of a patient or within a patient. The method can be carried out in vivo (e,g. within a patient) or ex vivo (e.g., outside of the body of a patient).
[0010] An RMS (root mean square) roughness of the surface can be less than about 10 nm, e.g., less than about 5 nm, e.g., between 0.5 nm and 10 nm.
[0011] In another general aspect, blood compatible articles as described herein include a substrate having a rough surface. The rough surface includes a plurality of three-dimensionally curved features each having a radius of curvature of less than about 50 nm, e.g., 5, 10, 15, 20, 25, 30, 35, 40, or 45 nm. The surface includes a sufficient concentration of features per unit area to limit blood coagulation activity on the substrate and to limit the number of platelets that adhere to the surface when the substrate is exposed to blood.
[0012] Embodiments can include one or more of the following features. The features can be substantially hemispherical. The rough surface can include a coating on the substrate, wherein the coating comprises the features. The features can include nanoparticles and a fill rate of the nanoparticles in the coating can be at least about 50%, e.g., at least about 60% or at least about 70%. The features can be nanoparticles having a diameter of less than about 100 nm, e.g., less than about 85 nm, e.g., between about 12 nm and about 85 nm, e.g., 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, or 80 nm. The diameter of the nanoparticles can be the average particle size of the nanoparticles as determined by a dynamic light scattering method.
[0013] The coating can be or include a ceramic, metal, metal oxide, or polymer material, or can be or include mixtures of one or more of these materials. The coating can be non-toxic and/or biocompatible.
[0014] The substrate can be a medical device or part of a medical device.
[0015] The concentration of the features can limit the adsorption onto the substrate of one or more proteins associated with coagulation. For example, the concentration of the features can limit the adsorption of Factor XII onto the substrate. For example, the limited coagulation activity can inhibit formation of a fibrin clot at the surface of the substrate. The concentration of the features can limit the activation of platelets adsorbed on the substrate. An RMS roughness of the surface can be less than about 10 nm, e.g., less than about 5 nm, e.g., between 0.5 nm and 10 nm.
[0016] The term “blood compatible” refers to the ability of a material to limit the activation of the blood coagulation system in the vicinity of the material and to prevent platelet adhesion to the material.
[0017] The blood compatible surfaces described herein have a number of advantages. For instance, medical devices that come into contact with a patient's blood can be treated with or manufactured with blood compatible surfaces to reduce adverse biological reactions associated with the use of such medical devices. The blood compatible surface can act as a barrier between the medical device and blood, thus allowing a wider range of materials to be used for the medical device itself. For instance, medical devices that exhibit or are treated with blood compatible coatings or surfaces can be formed of materials that are inexpensive, readily available, or easy to process, even if those materials are not biocompatible without the blood compatible coatings or surfaces.
[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.
[0019] Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1A is a diagram of a blood compatible coating formed of nanoparticles.
[0021] FIG. 1B is a diagram of a high curvature blood compatible coating.
[0022] FIG. 2 is a flow chart of a coagulation cascade.
[0023] FIG. 3 is a diagram of an implanted medical device.
[0024] FIGS. 4A-4D are atomic force microscopy images of blood compatible coatings of nanoparticles of different average diameters.
[0025] FIGS. 5A-5F are scanning electron microscopy images of blood compatible coatings of nanoparticles.
[0026] FIGS. 6A and 6B are a GISAXS (Grazing-incidence small-angle X-ray scattering) image and spectrum, respectively, for a blood compatible coating of 50 nm nanoparticles, respectively.
[0027] FIGS. 6C and 6D are a GISAXS image and spectrum, respectively, for a blood compatible coating of 12 nm nanoparticles.
[0028] FIGS. 7A-7D are plots of the time dependence of the intrinsic coagulation activity for nanoparticles in suspension as a function of particle size and concentration.
[0029] FIG. 8 is a plot of the intrinsic coagulation activity for nanoparticles in suspension as a function of nanoparticle size.
[0030] FIG. 9 is a plot of the intrinsic coagulation activity for nanoparticles in suspension as a function of nanoparticle size and concentration.
[0031] FIGS. 10A-10C are plots of the intrinsic coagulation activity on blood compatible coatings of nanoparticles of different sizes after incubation for 90 minutes, 180 minutes, and 300 minutes, respectively.
[0032] FIGS. 11A-11F are optical microscopy images of platelets adhered to blood compatible coatings of nanoparticles of different sizes.
[0033] FIG. 12 is a plot of the number of platelets adhered to blood compatible coatings of nanoparticles of different sizes.
DETAILED DESCRIPTION
[0034] As described herein, high curvature surfaces formed of features, such as nanoparticles, with a diameter or widest dimension, e.g., width, of less than about 100 nm, exhibit blood compatible properties. For instance, high curvature blood compatible surfaces can limit the intrinsic coagulation activity of blood in the vicinity of the surfaces, thus preventing the formation of fibrin clots at the coatings or surfaces. Furthermore, high curvature blood compatible surfaces can limit the adhesion of platelets, thus preventing the formation of platelet plugs and/or clots at the surfaces.
[0035] In some cases, when medical devices come into contact with the blood of a patient, adverse biological reactions can occur, such as blood coagulation and/or platelet accumulation. By coating medical devices with high curvature blood compatible surfaces, or by forming such devices with such surfaces, these adverse biological reactions can be mitigated.
Structure and Fabrication of Blood Compatible Coatings
[0036] Referring to FIGS. 1A and 1B , in one embodiment, a blood compatible coating 10 on a substrate 14 includes features with high curvature (i.e., materials with a small radius of curvature), such as three-dimensionally curved features that are approximately hemispherical. For instance, as shown in FIG. 1A , the blood compatible coating 10 can be formed of nanoparticles 12 that are disposed on the substrate 14 . In different examples, the nanoparticles 12 can have a diameter of less than about 100 nm, e.g., less than about 85 nm. For instance, in various examples, the nanoparticles 12 can have a diameter of about 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 85, 90, or 95 nm. In some examples, the root mean square (RMS) roughness of the blood compatible coating 10 is less than about 10 nm, or between about 0.5 nm and about 10 nm.
[0037] The nanoparticles 12 can be formed of a biocompatible material. In some examples, the nanoparticles 12 can be formed of a ceramic material, such as silica (SiO 2 ), titanium dioxide (TiO 2 ), zirconia (ZrO 2 ), zinc oxide (ZnO), aluminum oxide (Al 2 O 3 ), iron oxide (Fe 3 O 4 ), or another ceramic, such as a biocompatible ceramic. In some cases, the nanoparticles 12 can be fabricated, e.g., by solution-based synthesis procedures. In some cases, the nanoparticles 12 can be grown on the surface of the substrate 14 , e.g., in a vapor-phase deposition process, a flame spray pyrolysis approach, a chemical precipitation approach, or another approach to growing nanoparticles. In some examples, the nanoparticles 12 can be formed of polymers, such as biocompatible polymers. For example, polystyrene, polyethylene, polypropylene, polycaprolactone, polylactic acid, polyglycolide, poly(lactide-co-glycolide), polyacrylate derivatives, cellulose and chitin can be used to form the nanoparticles 12 .
[0038] In some examples, the nanoparticles 12 in the blood compatible coating 10 can interact with each other via chemical interactions such as van der Waals interactions, electrostatic interactions, hydrogen bonds, or another type of chemical interaction. In some examples, the nanoparticles 12 can be functionalized to bind together to form a cross-linked network of nanoparticles. For example, the nanoparticles 12 can be functionalized with ligands having end groups that can bind to other nanoparticles 12 or to the end groups of other ligands.
[0039] The substrate 14 can be any material that provides a desired function or property. For instance, the substrate 14 can be a medical device to be implanted into the body of a patient or a medical device that handles blood outside the body. For instance, if the coating 10 is applied to a coronary stent, the substrate 14 can be the material of the coronary stent. In some examples, the substrate 14 can be functionalized to chemically bind the nanoparticles 12 to the substrate 14 . For instance, the substrate 14 can be functionalized with siloxane-terminated molecules that can covalently bond to silica nanoparticles.
[0040] In some examples, the blood compatible coating 10 of nanoparticles 12 can be formed by spin coating a dispersion of nanoparticles 12 in alcohol, such as ethanol, onto the substrate 14 . For instance, a dispersion of nanoparticles 12 in ethanol can be spin-coated onto the substrate 14 . In some examples, the coating 10 of nanoparticles 12 can be formed by dip coating the substrate 14 into a dispersion of nanoparticles 12 in alcohol, such as ethanol. In some examples, the coating 10 can be annealed following spin or dip coating, e.g., to promote chemical interaction (e.g., van der Waals binding) between nanoparticles 12 in the coating 10 .
[0041] The thickness of the coating 10 of nanoparticles 12 can be less than 1 mm, e.g., less than about 500 nm, less than about 250 nm, less than about 100 nm, less than about 50 nm, less than about 25 nm, or less than about 10 nm. For instance, the coating 10 can be formed of about two layers of nanoparticles 12 , and thus the thickness of the coating 10 can be about twice the diameter of the nanoparticles 12 . A coating 10 formed of fewer than two layers of nanoparticles 12 can have exposed areas of substrate 14 , which reduces the effectiveness of the blood compatible coating 10 . If the coating 10 is too thick (e.g., thicker than about 1 mm), the coating 10 can easily crack.
[0042] The thickness of the coating 10 of nanoparticles 12 can be controlled by varying process parameters, such as the concentration of nanoparticles 12 in ethanol, the rotation speed of the spin coating, the acceleration of the spin coater, the number of repetitions of spin coating, and other parameters. For instance, the weight percent concentration of nanoparticles in ethanol can range from about 0.05 wt. % to about 10 wt. %, e.g., about 1.3 wt. %, about 3.0 wt. %, or about 4.0 wt. %. The rotation speed of the spin coating can range from about 100 rpm to about 10000 rpm, e.g., about 1000 rpm, about 2000 rpm, or about 3000 rpm. The acceleration of the spin coater can range from about 400 rpm/s to 4000 rpm/s.
[0043] The nanoparticles 12 in the coating 10 are densely packed. For instance, the fill rate (i.e., the percentage of space in the coating 10 that is occupied by nanoparticles 12 ) in the coating 10 is at least about 50%, e.g., at least about 60%, 65%, or 70%.
[0044] In some examples, other approaches to forming the blood compatible coating 10 of nanoparticles 12 can be used. In some cases, nanoparticles 12 can be spray-coated onto the substrate 14 . In some cases, nanoparticles 12 can be grown directly on the substrate 14 , e.g., in a vapor-phase deposition process. In some cases, nanoparticles 12 can be disposed on the surface by a Langmuir-Blodgett approach to forming coatings of nanoparticles, a layer-by-layer deposition of nanoparticles from a dispersion in a solvent, a spray pyrolysis approach, a chemical precipitation approach, or another approach. In the Langmuir-Blodgett method, a dispersion of nanoparticles in an organic solvent with appropriate surfactant is spread on a water surface to make a film of nanoparticles on the water surface. The film of nanoparticles is transferred to a solid surface from the water surface. In the layer-by-layer method, a positively charged nanoparticle dispersion and a negatively charged nanoparticle dispersion are prepared. When a base substrate is positively charged, the substrate is dipped into the negatively charged particle dispersion and then dipped into the positively charged particle dispersion. Nanoparticles are deposited on the base substrate by electric force. In the spray pyrolysis approach, a precursor solution is sprayed onto a substrate with heat under appropriate conditions. In chemical precipitation, a substrate is placed at the bottom of a precursor solution. Nanoparticles are created from the precursor solution by a reaction such as a redox reaction and precipitated onto the substrate directly.
[0045] Referring to FIG. 1B , in some embodiments, blood compatible surfaces 20 can include three-dimensional, highly curved features, such as bumps or peaks and valleys, on a surface 24 of a substrate 26 . The features can be approximately hemispherical. For instance, the radius of curvature of the features 22 can be less than 50 nm, e.g., less than about 42.5 nm. For instance, in one example, the features 22 can have a radius of curvature of about 2, 3, 4, 5, 6, 7, 10, 12, 15, 20, 25, 30, 35, 40, 45, or 50 nm.
[0046] The surfaces 20 can be formed by etching (e.g., wet etching or plasma etching) the surface 24 of the substrate 26 to form highly curved nanostructures 22 , such as bumps or peaks and valleys, on the surface 24 . For instance, surface features having a maximum radius of curvature of less than about 50 nm, or less than about 42.5 nm, can be etched into the surface. In some examples, the RMS roughness of the blood compatible coating 20 is less than about 10 nm, or between about 0.5 nm and about 10 nm.
[0047] Wet etch chemistries or plasma etch chemistries can be selected to etch the material of the substrate, e.g., to anisotropically etch the material of the substrate. In some cases, wet chemical etching using chemistries capable of etching silica can be used to form a nanostructured SiO 2 surface. Examples of wet etch chemistries capable of etching silica include, e.g., potassium hydroxide, tetramethylammonium hydroxide, ethylenediamine pyrocatechol, and hydrofluoric acid. In some cases, plasma etching using chemistries capable of etching silica can be used to form a nanostructured SiO 2 surface. Examples of plasma etch chemistries capable of etching silica include, e.g., hydrofluoric acid and buffered oxide etch (which includes ammonium fluoride and hydrofluoric acid). Other wet etch or plasma etch chemistries can be used to etch substrates of other compositions.
[0048] In some cases, the etched or machined nanostructured substrate can be applied to a medical device. In some cases, the surface of a medical device can itself be the substrate that is etched or machined such that highly curved nanostructures are formed directly on the medical device.
[0049] In some embodiments, blood compatible coatings can be formed by depositing a thin film of a material onto a substrate under deposition conditions that cause the thin film to have a high degree of roughness, such as an RMS roughness of less than about 10 nm, or between about 0.5 nm and about 10 nm. For instance, deposition conditions can be controlled to produce a surface with a roughness that correlates to surface features having a maximum radius of curvature of less than about 50 nm, or less than about 42.5 nm. In some cases, such a thin film can be deposited directly onto the surface of a medical device.
[0050] Other fabrication approaches can also be used to form surfaces with highly curved nanostructures. In some examples, substrates can be machined to form nanostructures on the surface of the substrates. In some examples, devices can be formed using a nano-imprinting approach, including forming a nanostructured surface from a mold that includes nanostructured features. For instance, a mold having nanostructured features can be formed using electron beam lithography or other lithography techniques or by forming a mold from a pre-existing nanoparticle layer. A high curvature polymer surface can be fabricated using thermal or photo nanoimprint lithography (NIL) based on a nanostructured mold. In the case of thermal NIL, a thermoplastic polymer film is formed on a substrate, and the mold is pressed into contact with the sample under appropriate pressure. When heated above the glass transition temperature of the polymer, the pattern on the mold is pressed into the softened thermoplastic polymer film. After cooling, the mold is separated from the sample and the pattern remains on the substrate. In the case of photo NIL, a photo-curable polymer liquid resist is applied to the sample substrate and the mold. After the mold and the substrate are pressed together, the resist is cured in UV light and becomes solid. After mold separation, a similar pattern transfer process can be used to transfer the pattern in resist onto the underneath material.
Uses of Blood Compatible Coatings and Surfaces
[0051] Blood compatible coatings can help to reduce the level of adverse biological reactions that occur when a foreign object comes into contact with blood, either within a subject's body or when a subject's blood passes through a device located outside the body. As shown in FIG. 2 , when a foreign object, such as a medical device, comes into contact with blood ( 200 ), an intrinsic blood coagulation pathway is activated that involves a cascade of proteolytic reactions (referred to as a coagulation cascade) that results in the formation of a fibrin clot at the foreign object. In particular, Factor XII (referred to as FXII) adsorbs onto the surface of the foreign object ( 204 ) and is denatured, thus activating to Factor XIIa (referred to as FXIIa) ( 206 ). For instance, hydrophilic or negatively charged surfaces are often highly active materials for FXII denaturation and activation. The intrinsic blood coagulation cascade begins ( 208 ) following the activation of FXII into FXIIa that ultimately result in the generation of thrombin ( 210 ), a substance that changes fibrinogen to fibrin and causes formation of a fibrin clot ( 212 ) in the vicinity of the foreign object. In addition, platelets can adhere to the foreign object ( 214 ), e.g., within minutes of the introduction of the foreign object into the blood. The adhered platelets can be activated ( 216 ), causing the formation of a platelet plug ( 218 ) in the region of the foreign object.
[0052] The presence of blood compatible surfaces can reduce the degree of intrinsic coagulation activity in blood exposed to the surfaces. That is, the ability of FXII to adsorb onto a blood compatible coating is less than the ability of FXII to adsorb onto a flat surface of the same composition, and thus the intrinsic coagulation cascade can be weakened in the presence of blood compatible surfaces. The reduced activity of the coagulation cascade due to blood compatible coatings can, in turn, limit the formation of fibrin clots in the vicinity of the coatings.
[0053] Furthermore, platelet adhesion can also be reduced in the presence of blood compatible surfaces. That is, the ability of platelets to adhere to a blood compatible surface is less than the ability of platelets to adhere to a flat surface of the same composition, and thus the degree of platelet adhesion can be reduced in the presence of a blood compatible surface. The reduced platelet adhesion to blood compatible surfaces can, in turn, limit the formation of platelet plugs at the surfaces.
[0054] Without being bound by theory, it is believed that the limited denaturation of FXII on blood compatible surfaces is due to the high surface curvature of the surfaces (e.g., the high curvature of the nanoparticles or surface features forming the blood compatible surfaces). Furthermore, the limited denaturation of platelets on blood compatible surfaces is also due to the high surface curvature of the surfaces. That is, high curvature surfaces of any composition can limit FXII denaturation and platelet adhesion, provided the concentration (per unit area) of highly curved features on the surface is sufficiently high. Such high curvature surfaces can thus significantly reduce the formation of fibrin clots and platelet plugs. For instance, a high curvature surface, such as a surface formed of SiO 2 nanoparticles, can be blood compatible even if the material of the surface (SiO 2 ) is not itself a blood compatible material.
[0055] Referring to FIG. 3 , in some embodiments, coating 10 can be applied as a coating for an implantable medical device 30 . For instance, the implantable medical device 30 can be coated with the coating 10 , e.g., by dip coating prior to implantation. In the example of FIG. 3 , the implantable medical device 30 is an artificial hip joint; however, the coating 10 can be applied to other implantable medical devices, such as other artificial joints, artificial blood vessels, stents, cochlear implants, pacemakers, implantable defibrillators, bone screws and plates, coronary stents, and other implantable medical devices. When the medical device 30 is implanted into a patient's body 32 , the blood compatibility of the coating 10 can reduce the occurrence or severity of adverse biological reactions, such as inflammation and/or formation of blood clots, associated with the implant. Moreover, the coating 10 can act as a barrier between the implanted medical device 30 and the body 32 , and thus a wider range of materials can be available to be used for the implanted medical device 30 . For instance, the implantable medical device 30 can be formed of a material that is inexpensive, readily available, not blood compatible, and/or not biocompatible.
[0056] In some embodiments, the coating 10 can be applied as a coating for medical devices that handle blood outside of the body. For instance, the coating 10 can be applied as a coating within dialysis equipment, blood donation and transfusion equipment, and other medical devices that handle, e.g., contain or transfer, blood outside of the body. The blood compatibility of the coating 10 can reduce the occurrence or severity of blood clots or other adverse reactions in the blood handled by the medical devices. Moreover, the coating 10 can act as a barrier between the medical devices and the blood handled by the devices, and thus a wider range of materials can be available to be used for the medical devices.
EXAMPLES
[0057] The invention is further described in the following examples, which do not limit the scope of the invention described in the claims.
[0058] The following examples show an approach to fabricating blood compatible coatings of nanoparticles. The examples further demonstrate intrinsic coagulation activity in suspensions of nanoparticles and on blood compatible coatings of nanoparticles. The examples also demonstrate platelet adhesion on blood compatible coatings of nanoparticles.
Example 1
Preparing Blood Compatible Coatings of Nanoparticles
[0059] Blood compatible coatings of silica nanoparticles of various sizes were fabricated on Si wafer substrates. 5 mL of silica nanoparticle dispersion in water (various sizes and manufacturers; see Table 1) was added to a vigorously stirred solution of 0.5 mL HCl (aq.) in 44.5 mL ethanol. The concentration of the 12 nm, 22 nm, 50 nm, and 85 nm nanoparticles in water was 40 wt. %; the concentration of the 7 nm nanoparticles in water was 30 wt. %; and the concentration of the 4 nm nanoparticles was 15 wt. %. Each nanoparticle dispersion in ethanol was placed in a 10K molecular weight cutoff dialysis membrane (Fisher Scientific) and dialyzed against ethanol several times.
[0000]
TABLE 1
Silica nanoparticles used to prepare blood compatible coatings
Nominal
Surface
Commercial
diameter
area
name
Provider
(nm)
(cm 2 /g)
AS
Alfa Aesar ® (Ward Hill, MA)
4
6.5 × 10 6
Ludox ® SM
Sigma-Aldrich ® (St. Louis, MO)
7
3.45 × 10 6
Ludox ® HS
Sigma-Aldrich ®
12
2.2 × 10 6
Ludox ® TM
Sigma-Aldrich ®
22
1.4 × 10 6
NexSil ™ 85
Nyacol ® Nano Technologies, Inc.
50
0.55 × 10 6
(Ashland, MA)
NexSil ™ 125
Nyacol ® Nano Technologies, Inc.
85
0.35 × 10 6
[0060] 1 cm 2 pieces of Si wafers were used as substrates. The substrates were sonicated in acetone and ethanol, dried under nitrogen flow, and treated by oxygen plasma for ten minutes. Immediately following the oxygen plasma treatment each dialyzed nanoparticle dispersion in ethanol was spin-coated onto a substrate at 3000 rpm for 160 seconds. The coated substrates were annealed at 100° C. for ten minutes and rinsed with DI water and ethanol.
[0061] The refractive index of each nanoparticle coating was measured by ellipsometry to be about 1.31. This refractive index corresponds to a fill rate of about 68% (i.e., nanoparticles occupy about 68% of the space in the coating), indicating that the nanoparticles in the coating are densely packed. Ellipsometry was performed using a Stokes Ellipsometer LSE (Gaertner® Scientific Corporation, Skokie, Ill.).
[0062] The thickness of the nanoparticle coatings can be varied by varying parameters such as the concentration of nanoparticles in ethanol and the rotation speed of the spin coating. Ellipsometry measurements of the thickness of each nanoparticle coating were performed at 9 points in each coating to quantify the uniformity of the coating. Coating thicknesses obtained for various nanoparticles sizes, concentrations, and rotation speeds are shown in Table 2. In general, the 9 measurements for each nanoparticle coating were within about 1 nm of each other, indicating a highly uniform thickness.
[0000]
TABLE 2
Thicknesses of blood compatible coatings of nanoparticles
Nominal
Concentration
Rotation speed
Thickness
diameter (nm)
(wt. %)
(rpm)
(nm)
85 nm
4.0
3000
≈220
85 nm
4.0
2000
≈182
85 nm
3.0
3000
≈100
85 nm
3.0
2000
≈113
85 nm
3.0
1000
≈146
22 nm
1.3
3000
≈69
22 nm
1.3
2000
≈91
22 nm
1.3
1000
≈130
[0063] Referring to FIGS. 4A-4D , atomic force microscopy (AFM) images were acquired for blood compatible coatings of nanoparticles with diameters of 85 nm, 50 nm, 22 nm, and 12 nm, respectively. These AFM images show that nanoparticles forming each of the blood compatible coatings are substantially uniform in size.
[0064] The root mean square (RMS) roughness of each coating was also determined by AFM. RMS roughness values are listed in Table 3 for a 500 nm×500 nm area of each coating. RMS roughness decreases monotonically with decreasing nanoparticle diameter, suggesting that the surface topology of the blood compatible coating can be controlled by controlling the size of the nanoparticles forming the coating. AFM imaging and measurements were performed in tapping mode using a DI-3000 atomic force microscope (Veeco, Plainview, N.Y.).
[0000]
TABLE 3
AFM and SEM characterizations of blood
compatible coatings of nanoparticles
Nominal
RMS roughness
Diameter (nm)
diameter (nm)
Thickness (nm)
(nm)
by SEM
4
≈40
—
7
7
≈120
—
9
12
≈65
0.93
16
22
≈85
1.84
27
50
≈180
3.76
68
85
≈180
6.61
104
[0065] FIGS. 5A-5F show scanning electron microscopy (SEM) images of nanoparticles of nominal diameter 85 nm, 50 nm, 22 nm, 12 nm, 7 nm, and 4 nm. SEM was used to characterize the thickness of the nanoparticle coatings and the actual diameter of the nanoparticles. These values are shown in Table 3. In general, the actual diameter of the nanoparticles was slightly larger than the nominal diameter of the nanoparticles (i.e., the diameter as provided by the manufacturer). In the following examples, the stated diameter of the nanoparticles is the nominal diameter of the nanoparticles. Field emission SEM imaging and measurements were performed with an S-5200 scanning electron microscope (Hitachi High Technologies, Tokyo, Japan).
[0066] Grazing-incidence small-angle X-ray scattering (GISAXS) was used to study the morphology and organization of the nanoparticle coatings. The beamline BL03XU at the SPring-8 synchrotron at the Japan Synchrotron Radiation Research Institute was used to generate X-rays at 12.4 keV and 8.3 keV. Small-angle X-ray scattering (SAXS) patterns were detected with a charge-coupled device (CCD) camera (1344×1024 pixels, 63 μm/pixel) positioned 2330 mm from the nanoparticle coating sample. The calibration of the angular scale was performed with a collagen standard sample (d-spacing: 65.3 nm). GISAXS was performed at incident angles above the critical angle of the silicon substrate (α c =0.1° at 12.4 keV).
[0067] FIGS. 6A and 6B show a GISAXS image and spectrum, respectively, for a blood compatible coating of 50 nm nanoparticles. FIGS. 6C and 6D show a GISAXS image and spectrum, respectively, for a blood compatible coating of 12 nm nanoparticles. Experimentally observed GISAXS spectra 60 , 62 and simulated GISAX spectra 64 , 66 are shown. The GISAXS spectra present sharp in-plane Bragg peaks, indicative of highly ordered nanoparticles in the coatings. The positions of the peaks can be used to calculate the diameter of the nanoparticles in the coatings. The results of these calculations are shown in Table 4. In plane, additional diffractions are observed at higher qx values for 12 nm and larger nanoparticles, indicative of scattering by the nanoparticles.
[0000]
TABLE 4
Nanoparticle diameters calculated from GISAXS spectra
Nominal
Diameter (nm) calculated
diameter (nm)
from GISAXS
85
114.2
50
71.7
22
29.9
12
17.4
7
10.6
4
—
Example 2
Coagulation Activity in Suspensions of Nanoparticles
[0068] The time dependent intrinsic blood coagulation activity was evaluated in suspensions of silica nanoparticles of different sizes. Flat SiO 2 glass was used as a control sample. Because FXII adsorption on the surface of the procoagulant (i.e., nanoparticles or flat glass) is a trigger of the coagulation cascade, the intrinsic coagulation activity depends on the surface area of the procoagulant. Thus, the intrinsic blood coagulation activity was also evaluated as a function of the total surface area of the silica nanoparticles in the suspensions.
[0069] To prepare nanoparticle samples for evaluation of the intrinsic coagulation activity in solution, a sample solution was formed of 10 mL of 0.1 M tris HCl, 0.6 mL of 5 N NaCl (aq)., 0.4 mL of 0.5 M CaCl 2 (aq), 0.5 mL of 2 mM phosphatidylserine (aq) (Sigma-Aldrich), 0.4 mL of 5 mM S-2238 (aq) (Chromogenix, Milan, Italy), and 0.5 mL of human plasma (Plasma Control N, Siemens Healthcare, Malvern, Pa.).
[0070] A dispersion of silica nanoparticles of the desired size (4 nm, 7 nm, 12 nm, 22 nm, 50 nm, and 85 nm diameter) was added at the desired concentration to achieve a desired total surface area of nanoparticles. DI water was added until the total volume of the sample was 18 mL. 180 μL aliquots of the sample were poured into a biologically inert MPC polymer (poly(2-methacryroyloxyethylphosphorylcholine)-coated 96-well plate (Lipidure®-Coat S-F96, NOF Corporation, Tokyo, Japan) and incubated at 37° C. for up to at least 450 minutes to enable the generation of thrombin by contact with samples. After incubation, the absorbance of each sample at 405 nm was measured in a microplate reader to quantify the amount of thrombin generated, which was used as a measure of coagulation activity.
[0071] To prepare flat glass control samples, glass cover slips were sonicated in acetone and ethanol and dried under nitrogen flow. The substrates were incubated in the sample solution (without nanoparticles) and evaluated as described above.
[0072] FIGS. 7A-7D show the time dependence of the intrinsic coagulation activity for nanoparticles of various sizes and for samples having 0.4 cm 2 total surface area of nanoparticles in the 180 μL aliquot ( FIG. 7A ), 2 cm 2 total surface area of nanoparticles ( FIG. 7B ), 4 cm 2 total surface area of nanoparticles ( FIG. 7C ), and 10 cm 2 total surface area of nanoparticles ( FIG. 7D ). The “flat” sample is a flat glass substrate with a surface area of 0.4 cm 2 . The vertical axis shows the optical density (O.D.) at 405 nm after incubation, which corresponds to the quantity of thrombin generated and is indicative of the coagulation activity.
[0073] When the surface area was 0.4 cm 2 of nanoparticles ( FIG. 7A ), only flat glass activated the intrinsic blood coagulation system, while nanoparticles were almost inactive. For higher surface areas, the activation of the coagulation system became more prominent for larger nanoparticles. For the highest surface area (10 cm 2 of nanoparticles; FIG. 7D ), all of the nanoparticles showed some activation of the intrinsic coagulation system. That is, smaller nanoparticles can inhibit the activation of the intrinsic blood coagulation to a greater degree than larger nanoparticles.
[0074] The intrinsic coagulation activity of nanoparticles with surface areas 2 cm 2 of nanoparticles and 4 cm 2 of nanoparticles after six hours (300 minutes) of incubation at 37° C. was also measured. An MPC polymer-coated well plate was used as a control due to its biologically inert properties.
[0075] As shown in the bar graph of FIG. 8 , the intrinsic coagulation activity after five hours of incubation has a clear dependence on the size of the nanoparticles, with the intrinsic coagulation activity decreasing with decreasing nanoparticle size. The vertical axis shows the O.D. at 405 nm. The intrinsic coagulation activity of the smallest nanoparticles (4 nm, 7 nm, and 12 nm) at 2 cm 2 surface area is generally comparable to the biologically inert MPC control sample.
[0076] As shown in the graph of FIG. 9 , the intrinsic coagulation activity after incubation for 90 minutes was measured as a function of nanoparticle size and concentration. The vertical axis shows the O.D. at 405 nm. Each nanoparticle size has a corresponding threshold concentration for the activation of coagulation activity, suggesting that the intrinsic coagulation pathway is activated only after critical quantities of FXII are adsorbed onto the pro-coagulant surface and activated to FXIIa. This threshold concentration shifts higher with decreasing nanoparticle size, suggesting that larger nanoparticles activate more FXII for a given nanoparticle concentration. That is, lower curvature (larger diameter) surfaces are more active in the coagulation system. These results agree with the results of FIGS. 6A-6D , in which flat glass was shown to be more active than even the largest tested nanoparticles.
[0077] Hydrodynamic measurements were performed with Zetasizer Nano (Malvern Instrument Ltd., Worcestershire, UK) to determine the size of the nanoparticle aggregates in the nanoparticle suspensions used in the experiments above. Table 5 below shows the average particle size for each nominal nanoparticle diameter at pH 9.0 and pH 7.4, respectively. In water of pH 9.0, silica nanoparticles are dispersed as almost single particle due to electric repulsion between particles, except for 4 nm diameter particles. That is, the average particle sizes of silica nanoparticles are almost same as the nominal diameter of the nanoparticles. In a solvent of pH=7.4, nanoparticles of all sizes aggregate. The increase in the aggregate size with increasing nominal nanoparticle diameter was not monotonic. Thus, the results above indicating the dependence of coagulation activity on nanoparticle diameter do not necessarily suggest that coagulation activity depends on the size of the nanoparticle aggregates, but rather that coagulation activity depends on the surface curvature of the features on the surface (i.e., the nanoparticles in the blood compatible coating).
[0000]
TABLE 5
Average particle size of nanoparticle aggregates
Nominal
Average particle size
Average particle size
diameter (nm)
at pH = 9 (nm)
at pH = 7.4 (nm)
4
11.5
22.7
7
7.7
14.7
12
9.0
18.6
22
17.9
31.4
50
55.6
66.8
85
80.9
94.2
Example 3
Coagulation Activity on High Curvature Blood Compatible Coatings
[0078] The intrinsic blood coagulation activity on substrates coated with high curvature blood compatible coatings formed of nanoparticles of various sizes was characterized. Flat SiO 2 substrates and biologically inert MPC polymer substrates were used as control samples.
[0079] Blood compatible coatings of silica nanoparticles were prepared as described in Example 1 to coat both sides of a 5 mmφ cover glass with blood compatible nanoparticle coatings. Flat SiO 2 substrates were prepared as described in Example 2.
[0080] A sample solution was formed of 10 mL of 0.1 M tris HCl, 0.6 mL of 5 N NaCl (aq)., 0.4 mL of 0.5 M CaCl 2 (aq), 0.5 mL of 2 mM phosphatidylserine (aq), 0.4 mL of 5 mM S-2238 (aq), and 0.5 mL of human plasma. 5 mm×5 mm glass cover slips were coated with nanoparticles according to the approach described in Example 1 and placed into an MPC coated 96-well plate. A 180 μL aliquot of the sample was poured over each cover slip and incubated at 37° C. for up to at least 300 minutes to enable the generation of thrombin by contact with substrates. After incubation, the absorbance of each sample at 405 nm was measured in a microplate reader to quantify the amount of thrombin generated, which was used as a measure of coagulation activity.
[0081] Referring to the bar graphs of FIGS. 10A-10C , the coagulation activity on nanoparticle coatings (measured as the optical density at 405 nm) was characterized after 90 minutes of incubation ( FIG. 10A ), 180 minutes of incubation ( FIG. 10B ) and 300 minutes of incubation ( FIG. 10C ). The vertical axis shows the O.D. at 405 nm. These results show that coagulation activity depends on the curvature of the coating (i.e., the diameter of the nanoparticles in the coating). After 90 min of incubation ( FIG. 10A ), flat glass activated coagulation to a nearly saturated level, while of the nanoparticle-coated surfaces barely activated the coagulation system. These data suggest that nanoparticle-coated surfaces are less active for intrinsic coagulation than a flat surface. After additional incubation, the coagulation system was gradually more activated by the nanoparticle-coated surfaces, as shown in FIGS. 10B and 10C . In general, less coagulation activity occurred on high curvature surfaces (i.e., coatings of small nanoparticles) than on flat glass. The coagulation activity decreased with decreasing nanoparticle size until the coating of 22 nm diameter nanoparticles, which demonstrated the least coagulation activity of the coatings studied. Still smaller nanoparticles showed increased coagulation activity, but the activity was smaller than the coagulation activity on flat glass.
[0082] The results for coagulation activity on surfaces are somewhat different from the results for coagulation activity in suspensions of nanoparticles (Example 2). In particular, coagulation activity in suspensions of nanoparticles decreased continuously with decreasing nanoparticle size, while a local minimum in coagulation activity was observed for the 22 nm diameter nanoparticle coating. Nanoparticles in blood compatible coatings are densely packed (Example 1), and thus the distance between nanoparticles in a coating is very short. For coatings formed of very small nanoparticles, such as 4 nm diameter nanoparticles, the distance between nanoparticles can be smaller than the size of the proteins involved in the coagulation activity (e.g., FXII). Without being bound by theory, it is believed that proteins may recognize coatings formed of very small nanoparticles as essentially flat surfaces, and hence the coagulation activity on such nanoparticle coatings can be increased.
Example 4
Platelet Adhesion on High Curvature Blood Compatible Coatings
[0083] To characterize the ability of nanoparticle coatings to prevent platelet adhesion, substrates coated with silica nanoparticle coatings of various sizes were incubated in the presence of platelets. Flat SiO 2 substrates and biologically inert MPC polymer substrates were used as control samples. The number and morphology of the platelets that adsorbed on each substrate were characterized.
[0084] Substrates with silica nanoparticle coatings and flat SiO 2 substrates were prepared on 1 cm 2 silicon wafer as described in Example 3. To prepare a flat MPC polymer coated surface, a 1 cm 2 Si wafer was sonicated in acetone and ethanol and dried under nitrogen flow. The substrate was then treated by oxygen plasma for 10 minutes. 0.5 wt. % MPC polymer (Lipidure®-CM5206, NOF Corporation, Tokyo, Japan) in ethanol was spin coated onto the substrate (3000 rpm, 160 seconds) and dried under ambient conditions.
[0085] Citrated pooled whole blood (Bioreclamation Inc., Westbury, N.Y.) was centrifuged at 300 G for 10 minutes, and the supernatant was collected as platelet rich plasma (PRP). Substrates were incubated with 1 mL PRP on an MPC polymer coated 24-well plate (Lipidure®-Coat S-F24, NOF Corporation, Tokyo, Japan) at 37° C. under the condition of 5% CO 2 for three hours. The substrates were rinsed with 0.1 M phosphate buffer and fixed following general procedure. The adsorbed platelets on each substrate were observed by optical microscopy and the number of platelets per 100 μm×100 μm area were counted.
[0086] FIGS. 11A-11F show optical microscopy images (scale bar: 20 μm) of platelets adhered to surfaces with coatings of nanoparticles with 4 nm diameter ( FIG. 11A ), 12 nm diameter ( FIG. 11B ), 22 nm diameter ( FIG. 11C ), and 85 nm diameter ( FIG. 11D ). Platelets adhered to a flat SiO 2 substrate ( FIG. 11E ) and a flat MPC polymer coating ( FIG. 11F ) are also shown. The coatings of 22 nm ( FIG. 11C ), 50 nm, and 85 nm ( FIG. 11D ) diameter nanoparticles adsorbed fewer platelets than the coatings of smaller nanoparticles. In addition, the platelets adsorbed on the larger nanoparticles had a rounder morphology than those adsorbed on the smaller nanoparticles. Round platelets are the least activated form of platelets. Thus, these optical microscopy images indicate that the platelets adsorbed on large nanoparticles are not highly activated, suggesting that blood clots may not form on coatings of large nanoparticles.
[0087] FIG. 12 shows a plot of the number of platelets adsorbed in 100 μm×100 μm area for each nanoparticle coating and for the two control samples. The number of platelets adsorbed to the flat SiO 2 sample was greater than the number of platelets adsorbed to any of the nanoparticle coatings, indicating that silica nanoparticles of 85 nm diameter or less prevent platelet adhesion more effectively than flat SiO2. The size of the nanoparticles does affect platelet adhesion: the coating of 7 nm diameter nanoparticles had the most adsorbed platelets and the coating of 85 nm diameter nanoparticles had the fewest adsorbed platelets. Moreover, the 85 nm diameter nanoparticle coating had fewer adsorbed platelets than the MPC polymer, which is a highly blood compatible material.
Other Embodiments
[0088] It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims. | 4y
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BACKGROUND TO THE INVENTION
This invention relates to a cylinder for a rotary web processing machine, and in particular to a cylinder which is constituted by a mandrel and a plurality of cutting and/or creasing rings detachably fixed thereto.
Rotary web processing machines are used for creasing and/or cutting webs of board, for example, for forming carton blanks. Such a machine has a pair of cylinders which are rotatably mounted in a frame in such a manner that the rings of the two cylinders are in alignment. The web to be processed is passed through the nip between the two cylinders, so that the web is creased and/or cut as it passes through the machine.
When cutting and/or creasing webs to form carton blanks, it is common practice to separate the functions of longitudinal cutting and/or creasing from those of transverse cutting and/or creasing. This is in order to alter one set of functions without affecting the other, or to facilitate independent adjustment of the penetration of the creasing and/or cutting surfaces of the rings into the web. In particular, it is often important to be able to move each of the rings accurately and interchangeably into different predetermined positions. Moreover, many rotary web processing machines require frequent ring changes to be made. For example, when making milk carton blanks, it is frequently desirable to change the lateral pitch of the creasing rings which form the tops and bases of the cartons. By changing the lateral positions of these creasing rings, it is possible to make milk cartons which have the same repeat lengths but are of different predetermined widths.
The cylinders of many known rotary web processing machines have one-piece creasing rings which are threaded onto a key-wayed mandrel, the lateral positions of the rings being determined by spacing rings (or tubes) positioned between adjacent pairs of creasing rings. Consequently, when it is required to re-position the creasing rings on the mandrel of such a cylinder, it is necessary to carry out the following steps:
(a) the mandrels must be removed from the web processing machine;
(b) the creasing rings and spacing rings must then be removed from the mandrels;
(c) the creasing rings must be replaced on the mandrels with different spacing rings positioned therebetween; and
(d) the mandrel must then be repositioned in the web processing machine.
Obviously, this process is very time consuming, and so is extremely disadvantageous when frequent ring changes must be made.
In order to avoid the difficulties with this type of cylinder, it is known to use two-part creasing rings which can be clamped to a mandrel in a variety of positions. The two parts (segments) of each ring can be drawn together to clamp that ring to the mandrel using parallel screws across the adjoining surfaces of the segments. This method of drawing the segments together is often inconvenient, in that it is difficult to arrange for the screw heads to be accessibly positioned on the periphery of the segments. Moreover, although the rings can generally be positioned anywhere along the axis of the mandrel, radial location is difficult. Thus, radial location is generally provided by a key and slot arrangement between the mandrel and each ring, and this is invariable without the provision of further attachments. The rings may be held in predetermined positions by means of spacers positioned therebetween. Alternatively, this can be accomplished by dowel pins fixed to the segments and extending towards the corresponding segments of the adjacent ring.
Alternatively, the segments of each ring can be fixed to the mandrel by radial screws. In this case, two dowel pins are used for axial and radial location of each of the segments. Here again, however, it is extremely difficult to vary the radial location of each of the rings. In particular, unless the two dowel pins of each segment are parallel, they would have to be retractable to enable the segments to be removed. Retractable dowel pins complicate the arrangement and add to the number of steps required to fit and remove the rings. Thus, when frequent ring changes are necessary, this type of fitting is disadvantageous. Moreover, the constant insertion and removal of the dowel pins leads to excessive wear of the bores provided for them in the mandrel. The provision of parallel dowel pins would mean providing non-radial bores in the mandrel, and this would entail great difficulties in ensuring accurate radial location of the rings in interchangeable positions. Thus, although cylinders of this type permit relatively easy axial repositioning of the creasing rings, they suffer from a major disadvantage that it is extremely difficult, if not impossible, to position the creasing rings accurately (in both radial and axial directions) in different predetermined positions. Moreover, cylinders of this type are not suitable where frequent ring changes are necessary. (Cylinders of this type are described in U.S. Specification No. 1547214 & GB Patent Specification No. 871450).
The aim of the invention is to provide a cylinder for a rotary web processing machine whose rings can easily be removed and re-positioned accurately in both radial and axial directions, without requiring its mandrel to be removed from its bearings.
SUMMARY OF THE INVENTION
The present invention provides a cylinder for a rotary web processing machine, the cylinder comprising a mandrel and a plurality of multi-part rings detachably fixed thereto, wherein each part of each ring is fixed to the mandrel by first and second screws, each first screw being effective to clamp the associated ring part to the mandrel and to locate that ring part both radially and axially, each second screw being effective to clamp the associated ring part to the mandrel.
Preferably, each of the rings is of two-part construction, each of said parts being a half ring.
Preferably, the mandrel is provided with a plurality of sets of threaded bores, the bores of each set being adapted to receive the screws of one of said rings, there being a greater number of sets of bores than there are rings, and the sets of bores being spaced along the mandrel so that the rings can be fixed to the mandrel at different spacings.
Preferably, each first screw is received with respective bushes mounted in apertures formed in the associated ring part and the mandrel, each of the apertures in the mandrel being aligned with a respective threaded bore. Preferably, the bushes are made of harder material than the rings and the mandrel.
Advantageously, the adjacent edge portions of each pair of adjacent ring parts are formed with aligned grooves, a respective key being positioned within each pair of aligned grooves to align the associated ring parts. Preferably, each key is detachably connected to the associated ring parts by means of screws.
BRIEF DESCRIPTION OF THE DRAWINGS
A web processing machine incorporating two cylinders constructed in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of part of the machine;
FIG. 2 is a perspective view of part of one of the cylinders of the machine of FIG. 1; and
FIG. 3 is a sectional view showing the method of connecting a creasing ring to the mandrel of one of the cylinders.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, FIG. 1 shows a cylinder assembly of a rotary web processing machine which is used for forming the crease markings on milk carton blanks. This assembly is removably mounted in the frame of the machine (not shown). The assembly has a pair of side plates 1 which rotatably support a pair of cylinders 2. Each of the cylinders 2 is constituted by a cylindrical shaft 3, a hollow tubular mandrel 4 fixed to the shaft 3, and four creasing rings 5 detachably fixed to the mandrel. The end portions of the shafts 3 are supported in the side plates 1 by means of bearings 6. At one side of the assembly the free ends of the shafts 3 are provided with gear wheels 7. The gear wheels 7 intermesh so that, when one of the gear wheels is driven from the machine by a motor (not shown), the two shafts 3 rotate in opposite directions in synchronism. The shafts 3 are mounted in the side plates 1 in such a manner that the creasing rings 5 of the two cylinders 2 define a nip through which a web 88 of board can pass. One of the cylinders 2 is arranged to be vertically adjustable, so that the size of the nip can be varied. This enables webs of different thicknesses to be processed by the machine, and also permits the degree of penetration of the creasing rings 5 into the web 88 to be varied.
Each of the creasing rings 5 is constituted by two identical parts 5a. Each ring part 5a is detachably fixed to the mandrel 4 by means of two screws 8 and 9. Each screw 8 is an axial and radial locating screw and a clamping screw, and each screw 9 is a radial clamping screw. The radial clamping screws 9 pass through aligned apertures 9a and 9b formed respectively in the associated ring part 5a and the mandrel 4. Each axial and radial locating and clamping screw 8 passes through hardened bushes 10 and 11 formed respectively in aligned apertures 8a and 8b formed respectively in the associated ring part 5a and the mandrel 4. As shown in FIG. 3, the apertures 8a and 8b are stepped, and the screws 8 each have a head 8d, a smooth cylindrical shank 8e and a threaded shank 8f. The threaded shank 8f of each screw 8 engages within a threaded portion 8g of the associated aperture 8b in the mandrel 4.
The cylindrical surface of each ring part 5a is formed with a respective key slot 12. The two key slots 12 of one part 5a of each ring 5 are adapted to be aligned with the key slots 12 of the other part 5a of that ring. A respective key 13 is provided for engaging within each pair of aligned key slots 12, and a pair of screws 14 are provided for fixing each of the keys to the associated ring parts 5a. The keys 13 are used to hold the ring parts 5a together prior to assembly of the rings 5 onto the mandrel 4.
As shown best in FIG. 2, the mandrel 4 is provided with a plurality of sets of apertures 8b and 9b, each set having a pair of diametrically opposed apertures 8b for accommodating the screws 8, and a pair of diametrically opposed apertures 9b for accommodating the screws 9. The mandrel 4 is provided with a considerably greater number of sets of apertures 8b and 9b than there are rings 5, so that the rings 5 can be fixed to the mandrel at different locations and spacings.
In order to fix a ring 5 on its mandrel 4, the two parts 5a thereof are loosely held together by engaging the keys 13 in the aligned key slots 12, and by loosely threading in the fixing screws 14. The two axial and radial locating and clamping screws 8 are then threaded through the apertures 8a in the rings parts 5a, and into the apertures 8b in the mandrel 4. The cylindrical shanks 8e of the screws 8 engage within the bushes 10 and 11 to effect accurate alignment of the rings parts 5a both radially and axially with respect to the mandrel 4. The screw threaded portions 8f and 8g then engage to clamp the rings parts 5a to the mandrel 4. The radial clamping screws 9 are then screwed into position to clamp the rings parts 5a firmly to the mandrel 4. The screws 14 are then tightened up to complete the fixing of the ring 5.
If a ring 5 is required to be repositioned (for example where the rings 5 of a given cylinder 2 have to be repositioned laterally in order to make milk carton blanks of different widths), it is necessary only to loosen the screws 14 to remove the screws 8 and 9, to slide the ring along the mandrel 4 to the new position, and then to replace the screws 8 and 9 and retighten the screws 14. Obviously, this procedure is considerably simpler and less time-consuming than the equivalent procedure for replacing the one-piece creasing rings of the known type of web processing machine. In particular, there is no need to remove the cylinders 2 from the assembly to carry out the lateral repositioning of the creasing rings 5. Moreover, the provision of the axial and radial locating and clamping screws 8 ensures that the rings 5 are always accurately positioned both axially and radially. Moreover, the repositioning process is both rapid and easy, so frequent ring changes cause no problems. In this connection, the provision of the hardened bushes 10 and 11 substantially reduces wear, and so increases the life of the mandrel. Obviously, where the repositioning of the creasing rings 5 requires the addition of one or more rings 5 this can easily be accomplished by fixing the two parts 5a of a new ring onto the mandrel 4 at the required position. Similarly, where a ring 5 needs to be removed, this is easily accomplished by completely removing the screws 14 of the ring concerned, and separating the two ring parts 5a of that ring. | 4y
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FIELD OF DISCLOSURE
[0001] The present disclosure relates generally to digital memory subsystems, and more particularly, to a method and system that provides power management of memory channels within a memory subsystem.
BACKGROUND
[0002] Increases in processor performance and the development of multi-core, multi-threaded processors have led to a rapidly increasing need for more memory bandwidth and capacity. To keep up with the increasing demands for data bandwidth and capacity, memory subsystems have had to increase both their frequency of operation and density. Many conventional systems provide power management with system-level temperature control via feedback cooling systems and/or system-level voltage/current control. Cooling systems are designed to reduce the overheating of the memory subsystem as a whole. Designing cooling systems to provide sufficient cooling capacity for these high density memory systems can be difficult as the cooling systems have to keep up with the increasing density of memory chips.
[0003] High power consumption in mobile devices also remains a challenging issue. The high bandwidth requirements of high end mobile devices, for example mobile phones and PDAs, exacerbate the problem. A memory channel consumes different amounts of power depending on its power mode or state, but the power mode also affects the memory bandwidth. A “power down” state uses the least power as it shuts off the memory channel, but during the power down state, the memory channel cannot be accessed. Entering and exiting the power down state can also have a significant performance overhead. In an “operation” state the memory channel consumes more power but is ready to respond to memory requests.
[0004] There can be more than one level or power mode in the operation state of a memory channel. In general, levels with greater throughput or bandwidth have greater power requirements. Many current memory systems use wire bond or off chip double data rate (DDR) memory. The number of interconnects between the DDR memory and processors is limited, and thus supporting multiple channels with separate input/output and V dd would be difficult. Other systems use a technique of powering down the memory channel. To power down the channel, the channel can not be accessed, and there is a performance overhead in entering and exiting the power down state.
[0005] Thus, it would be desirable to reduce the power consumption of the memory devices without having a significant impact on the memory bandwidth or capacity.
SUMMARY
[0006] Disclosed is a memory power management system supporting multiple power modes. The memory power management system can include a memory controller, a throughput detector, power control logic and a power control device. The memory controller controls a memory channel. The throughput detector detects a requested throughput of the memory channel. The power control logic determines a desired power mode corresponding to the requested throughput of the memory channel, where the desired power mode is one of the multiple power modes. The power control device supplies a desired voltage to the memory channel where the desired voltage corresponds to the desired power mode.
[0007] The throughput detector and the power control logic can be part of the memory controller. The power control device can be a voltage regulator that includes a voltage input for receiving a supply voltage, and a power circuit for transitioning the supply voltage to the desired voltage. The power control device can be a voltage selector that includes a plurality of selectable voltages, each of the selectable voltages corresponding to one of the plurality of power modes; and a selector device that selects the desired voltage from the plurality of selectable voltages. The plurality of selectable voltages can be supplied by a power management circuit. The memory power management system can include a memory crossbar, where the throughput detector is integrated into the memory crossbar. The power control device can also supply the desired voltage to the memory controller.
[0008] The memory power management system can include multiple memory controllers for controlling a multi-channel memory, where each memory controller controls one channel of the multi-channel memory. For a multi-channel memory, the throughput detector can detect a requested throughput for each memory channel; the power control logic can determine a desired power mode for each memory channel corresponding to the requested throughput for that memory channel; and the power control device can supply a desired voltage to each memory channel of the multi-channel memory, the desired voltage for each memory channel corresponding to the desired power mode for that memory channel.
[0009] Also disclosed is a method for controlling the power applied to a memory channel. The method performs functions of detecting a requested throughput for the memory channel; determining a desired voltage related to the requested throughput; requesting the desired voltage from a voltage device; and applying the desired voltage to the memory channel. The method can also include determining whether the desired voltage is different from a current voltage being supplied to the memory channel; and only performing the requesting and applying functions when the desired voltage is different from the current voltage being supplied to the memory channel. The method can limit when the requesting and applying functions are performed to only when the desired voltage is different from the current voltage being supplied to the memory channel, and the desired voltage does not change for a threshold time duration. Alternatively, the requesting and applying functions are performed only when the desired voltage is different from the current voltage being supplied to the memory channel, and the desired voltage does not change for at least a portion of a threshold time duration.
[0010] The function of determining a desired voltage can include comparing the requested throughput to a set of threshold throughput values, and setting the desired voltage equal to a threshold voltage value associated with the threshold throughput value closest to but less than the requested throughput. Alternatively, the function of determining a desired voltage can include plugging the requested throughput into a function relating throughput to voltage; and setting the desired voltage equal to the result of the function when plugging in the requested throughput.
[0011] Also disclosed is a memory power control apparatus for a multi-channel memory that includes a throughput detector system, a power control logic system and a power mode supply system. The throughput detector system determines a requested throughput for each channel of the multi-channel memory. The power control logic system determines a desired power mode associated with the requested throughput for each channel of the multi-channel memory. The power mode supply system, which is controlled by the power control logic system, supplies a desired voltage to each channel of the multi-channel memory. The memory power control apparatus can also include a plurality of memory controllers, where the throughput detector system is integrated into the plurality of memory controllers. Alternatively, the memory power control apparatus can include a memory crossbar with the throughput detector system integrated into the memory crossbar.
[0012] The memory power control apparatus can also include multiple memory controllers with each memory controller controlling one channel of the multi-channel memory. The throughput detector system and the power control logic system can be integrated into the multiple memory controllers.
[0013] The power mode supply system can include a power management circuit and a power distribution circuit. The power management circuit provides a plurality of selectable voltages. The desired voltage for each channel of the multi-channel memory is one of the plurality of selectable voltages. The power distribution circuit routes the desired voltage for each channel of the multi-channel memory to the appropriate channel.
[0014] In some embodiments, the power control logic of the memory power control apparatus only triggers the power mode supply system to supply the desired voltage to a channel of the multi-channel memory when the desired power mode for that channel remains unchanged for a threshold time duration.
[0015] For a more complete understanding of the present disclosure, reference is now made to the following detailed description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic of a digital system with multi-channel memory;
[0017] FIG. 2 is a schematic of a memory controller connected to a memory channel;
[0018] FIG. 3 is a schematic of an alternative embodiment of a memory controller connected to a memory channel;
[0019] FIG. 4 is a schematic of an alternative digital system with multi-channel memory;
[0020] FIG. 5 is a flow diagram of an exemplary control algorithm for a power management system; and
[0021] FIG. 6 is a block diagram showing an exemplary wireless communication system in which a memory power management system supporting multiple power modes may be advantageously employed.
DETAILED DESCRIPTION
[0022] FIG. 1 shows a schematic of a digital system 10 comprising a plurality of processors 102 - 106 ; a memory crossbar 120 ; and a multi-channel memory subsystem 124 which comprises a plurality of memory controllers 130 - 136 , each of the memory controllers 130 - 136 being coupled to a memory channel 140 - 146 . In this embodiment the memory crossbar 120 serves as an interface between the processors 102 - 106 and the multi-channel memory subsystem 124 . Other interfaces between the processors and memory channels can also be used. The processors 102 - 106 are each coupled to the crossbar 120 as a master device (M) and the memory controllers 130 - 136 are each coupled to the crossbar 120 as a slave device (S). The processors 102 - 106 send memory requests to the crossbar 120 , the memory requests are routed to the appropriate memory controller 130 - 136 , the appropriate memory controller 130 - 136 accesses the associated memory channel 140 - 146 to fulfill the memory request and sends any necessary response back to the processor 102 - 106 that initiated the memory request.
[0023] Two important parameters in a digital system are system speed or performance and system power consumption. Power consumption is an especially important factor in mobile systems where it directly affects the amount of time a battery charge can power the system. The speed with which the memory requests of the processors 102 - 106 can be fulfilled by the memory subsystem 124 has a significant impact on the overall system speed. Thus, it is advantageous to maximize the throughput or bandwidth of the memory system 124 in order to increase the overall speed of the system. However, the memory subsystem 124 also impacts the power consumption of the overall system. The lower the voltage supplied to the memory channel, the lower the power consumed by the memory channel, but the lower the bandwidth of the memory channel, i.e., the slower the rate at which data can be read from or stored to the memory channel. Thus, there is a trade-off between memory bandwidth and memory power consumption.
[0024] A memory channel consumes different amounts of power depending on its state. The “power down” state uses the least power, but during the power down state, the memory channel cannot be accessed and entering and exiting the power down state has a significant performance overhead. In an “operation” state the memory channel consumes more power but it is ready to process memory requests. The operation state can have multiple levels or power modes. In general, levels with greater throughput or bandwidth will have greater power requirements. Each memory channel can operate in different power modes with different voltage and frequency. An exemplary embodiment of the multi-power mode system has three power modes: (1) high bandwidth/high power, (2) medium bandwidth/medium power, and (3) low bandwidth/low power. The power down feature can also be used as an additional power option in this memory architecture. In the low bandwidth/low channel mode, the memory channel can still be accessed unlike the power down mode.
[0025] In the embodiment shown in FIG. 1 , the memory controller for each channel controls the power mode of the channel. For example, if the processors 102 - 106 are making frequent memory requests to the memory channel 140 , then it would be desirable for the memory controller 130 to raise the voltage for the memory channel 140 to allow for increased bandwidth or throughput to fulfill the memory requests faster. Meanwhile, if the processors 102 - 106 are making less frequent memory requests to the memory channel 146 , then it would be desirable for the memory controller 136 to adjust the voltage for the memory channel 146 to be in a medium or low power mode. And if the processors 102 - 106 are making even fewer memory requests of the memory channel 142 for an extended period of time, then it would be desirable for the memory controller 132 to adjust the voltage for the memory channel 142 to be in low power mode or even in power down mode.
[0026] As an example of the potential power savings, assume there are four memory channels with requested throughputs of 1.5 gigabytes per second (GB/s), 1 GB/s, 1 GB/s, and 1 GB/s, respectively. The former method would be to run all channels at the same power mode, for example 1.8 V and 333 Mhz with a power efficiency of 0.4 Watts/GB/s, which results in a total power consumption of:
[0000] 0.4 Watts/GB/s*(1.5+1+1+1) GB/s=1.8 Watts.
[0000] Assume that the higher throughput, 1.5 GB/s, has the above desired power mode but the slower rate of 1 GB/s has a desired power mode with voltage of 1.2 V, clock frequency of 266 Mhz and power efficiency of 0.14 Watts/GB/s. By running each channel at its desired power mode, the total power consumption is reduced to:
[0000] 0.4 Watts/GB/s*1.5 GB/s+0.14 Watts/GB/s*(1+1+1) GB/s=1.0 Watts.
[0000] In this example, running the memory channels in multiple power modes reduced the total power consumption by more than 44%.
[0027] FIG. 2 shows an exemplary embodiment of a memory controller 202 coupled to a memory channel 204 . The memory controller 202 can be exemplary of any of the memory controllers 130 - 136 . The memory channel 204 can be exemplary of any of the memory channels 140 - 146 . The memory controller 202 receives memory requests through lines 206 which couple the memory controller 202 , directly or indirectly, to the processors 102 - 106 . The memory controller 202 then communicates with the memory channel 204 across lines 208 to fulfill the memory requests. The memory controller 202 includes power control logic (PCL) 210 and a voltage regulator (VR) 212 . The power control logic 210 keeps track of the requested memory throughput and determines a desired power level for the memory channel 204 based, at least in part, on the requested memory throughput. The desired power level may be determined by various methods, for example, using threshold values, a look-up table, or a function relating power mode to throughput. If the power control logic 210 determines that the power mode of the memory channel 204 should be changed to a new power mode, the power control logic 210 signals the voltage regulator 212 to change to the new power mode. The voltage regulator 212 then adjusts the voltage supplied to the memory channel 204 through a power connection 214 . The voltage or voltages available to the voltage regulator 212 can be generated external to the memory controller 202 , for example by a power management circuit for the system.
[0028] FIG. 3 shows an alternative exemplary embodiment of a memory controller 302 coupled to the memory channel 204 . The memory controller 302 can be exemplary of any of the memory controllers 130 - 136 . The memory controller 302 receives memory requests through lines 206 which couple the memory controller 302 to the processors 102 - 106 . The memory controller 302 then communicates with the memory channel 204 across lines 208 to fulfill the memory requests. The memory controller 302 includes power control logic (PCL) 210 and a voltage selector 312 . In this illustrative schematic, the voltage selector 312 is shown as a switch with three voltage choices: V high , V med and V low . V high can be a high power/high bandwidth power mode; V med can be a medium power/medium bandwidth power mode; and V low can be a low power/low bandwidth power mode. As in FIG. 2 , the power control logic 210 keeps track of the requested memory throughput and determines a desired power mode for the memory channel 204 based, at least in part, on the requested memory throughput. If the power control logic 210 determines that the power mode of the memory channel 204 should be changed to a new power mode, the power control logic 210 signals the voltage selector 312 to change to the new power mode. The voltage selector 312 then selects the voltage for the desired power mode which is supplied to the memory channel 204 through power connection 214 . The voltages available to the voltage selector 312 can be generated external to the memory controller 302 , for example by a power management circuit for the system.
[0029] An alternative system embodiment is shown in FIG. 4 , where the same reference numbers are used for similar elements. FIG. 4 includes the multiple processors 102 - 106 coupled through the memory crossbar 120 to a multi-channel memory system 424 comprising multiple memory controllers 430 , 432 , 434 , 436 each coupled to memory channels 140 , 142 , 144 , 146 , respectively. The memory controllers 430 - 436 do not include power control logic or voltage control. In the system of FIG. 4 , power control logic 402 is external to the memory controllers, and the power control logic 402 is coupled to a power management circuit 404 . The power control logic 402 tracks the power mode of each memory channel. FIG. 4 shows an embodiment where the power control logic 402 is coupled to the memory crossbar 120 for receiving the requested throughput for each memory channel 140 - 146 from the memory crossbar 120 . Alternatively, the power control logic 402 can be coupled to each of the memory controllers 430 - 436 and receive the requested throughput for each memory channel 140 - 146 from the memory controllers 430 - 436 . The power control logic 402 determines a desired power mode for each of the memory channels 140 - 146 based, at least in part, on the requested memory throughput of the memory channel. If the power control logic 402 determines that the power mode of a particular memory channel should be changed to a new power mode, the power control logic 402 signals the power management circuit 404 to change to the new power mode for that particular memory channel. The power management circuit 404 then adjusts the voltage supplied to the particular memory channel through the connection between the power management circuit 404 and that particular memory channel. Alternatively, the power management circuit 404 can adjust the voltage supplied to both the particular memory channel and the memory controller associated with the particular memory channel.
[0030] FIG. 5 provides a top-level flow diagram of an exemplary control algorithm for the power control logic (PCL) 402 or 210 to determine the power mode for a memory channel. For a multi-channel memory, this control logic can be duplicated for each channel, for example as in FIGS. 2 or 3 , or the control logic can control multiple memory channels, for example as in FIG. 4 ; and each channel can be powered at its particular desired power mode.
[0031] At block 502 , the PCL determines the requested throughput for the memory channel. At block 504 , the PCL determines the desired power mode for the requested throughput level found in block 502 . At block 506 , the PCL checks whether the memory channel is already operating at the desired power level. If the memory channel is already operating at the desired power level then control is passed back to block 502 , otherwise control is passed to block 508 . In an alternative embodiment, if the memory channel is not already operating at the desired power level then control is passed directly to block 516 where the PCL initiates transition of the memory channel to the desired power level, and then control is passed back to block 502 .
[0032] At block 508 , the PCL again determines the requested throughput for the memory channel. At block 510 , the PCL determines the associated power mode for the requested throughput level found in block 508 . At block 512 , the PCL checks whether the desired power mode determined in block 504 is the same as the associated power mode determined in block 5 10 . If the desired and associated power modes are not the same, then the memory channel is fluctuating between different desired power modes and control is transferred back to block 502 . Otherwise, control is passed to block 514 . In an alternative control algorithm, instead of returning directly to block 502 when the desired power mode changes, the algorithm can check whether the memory channel returns to the same desired power level in less than a short threshold time. If the desired power level for the memory channel does return in the short threshold time, the algorithm passes control to block 514 , otherwise it passes control to block 502 .
[0033] At block 514 , the PCL checks whether the memory channel has been seeking the same desired power mode for at least a threshold period of time. This threshold can be selected to prevent the PCL from rapidly shifting or bouncing between power modes. If the desired power mode has not been sought for the threshold period of time, then control is passed to block 508 to see whether the memory channel stays in the range for the desired power mode. If the desired power mode has been sought for at least the threshold period of time, then control is passed to block 516 where the PCL initiates the transition of the memory channel to the new desired power mode, after which control is passed back to block 502 .
[0034] FIG. 6 shows an exemplary wireless communication system 600 in which an embodiment of a memory power management system supporting multiple power modes may be advantageously employed. For purposes of illustration, FIG. 6 shows three remote units 620 , 630 , and 650 and two base stations 640 . It should be recognized that typical wireless communication systems may have many more remote units and base stations. Any of remote units 620 , 630 , and 650 may include a memory power management system supporting multiple power modes such as disclosed herein. FIG. 6 shows forward link signals 680 from the base stations 640 and the remote units 620 , 630 , and 650 and reverse link signals 690 from the remote units 620 , 630 , and 650 to base stations 640 .
[0035] In FIG. 6 , remote unit 620 is shown as a mobile telephone, remote unit 630 is shown as a portable computer, and remote unit 650 is shown as a fixed location remote unit in a wireless local loop system. For example, the remote units may be cell phones, hand-held personal communication systems (PCS) units, portable data units such as personal data assistants, or fixed location data units such as meter reading equipment. Although FIG. 6 illustrates certain exemplary remote units that may include a memory power management system supporting multiple power modes as disclosed herein, the memory power management system is not limited to these exemplary illustrated units. Embodiments may be suitably employed in any electronic device in which a memory power management system supporting multiple power modes is desired.
[0036] While exemplary embodiments incorporating the principles of the present invention have been disclosed hereinabove, the present invention is not limited to the disclosed embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | 4y
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FIELD OF THE INVENTION
The present invention generally relates to magnetic recording heads and, in particular, relates to reducing the thermal protrusion of a near field transducer (NFT) in an energy-assisted magnetic recording (EAMR) head.
BACKGROUND OF THE INVENTION
To increase the areal storage density of a magnetic recording device, the recording layer thereof may be provided with smaller and smaller individual magnetic grains. This reduction in grain size soon reaches a “superparamagnetic limit,” at which point the magnetic grains become thermally unstable and incapable of maintaining their magnetization. The thermal stability of the magnetic grains can be increased by increasing the magnetic anisotropy thereof (e.g., by utilizing materials with higher anisotropic constants). Increasing the magnetic anisotropy of the magnetic grains, however, increases their coercivity and therefore requires a stronger magnetic field to change the magnetic orientation of the grains (e.g., in a write operation).
Energy-assisted magnetic recording (EAMR) is used to address this challenge. In an EAMR system, a small spot where data is to be written is locally heated to reduce the coercivity of the magnetic grains therein for the duration of the write operation, thereby allowing materials with increased magnetic anisotropy to be used, and greater areal storage density to be exploited.
To reduce the size of the spot which is heated, a near field transducer (NFT) is used to concentrate optical energy in the near field to dimensions much smaller than the diffraction limit would otherwise allow. With a NFT, a nano-sized spot can be heated to assist the magnetic writing on the magnetic media. Due to the less-than-ideal NFT conversion efficiency, some of the optical energy provided on the NFT is absorbed by the materials near an air-bearing surface (ABS) surrounding the NFT, and heat-related protrusion and of the NFT and the surrounding materials may occur.
SUMMARY OF THE INVENTION
Various embodiments of the present invention solve the foregoing problem by modifying the ABS of the EAMR head to compensate for the NFT protrusion, thereby preventing protrusion-related damage to the NFT which may occur. These approaches provide a reliable method of forming EAMR heads without the aforementioned problems, and can greatly enhance reliability of the EAMR heads.
According to one embodiment of the subject disclosure, a method of fabricating an energy assisted magnetic recording (EAMR) head to compensate for a heat-induced protrusion of a near field transducer formed therein can comprise applying optical power to the near field transducer to generate heat therein, whereby the near field transducer protrudes beyond an air bearing surface of the EAMR head. The method can further include removing a protruded portion of the near field transducer.
According to another embodiment of the subject disclosure, an energy assisted magnetic recording (EAMR) head is provided. The EAMR head can comprise a slider having a leading edge, a trailing edge, and an air bearing surface (ABS). The EAMR head can further comprise a near field transducer disposed in the slider and having a distal end proximate the ABS. The distal end of the near field transducer is recessed from the ABS when no optical power is applied to the near field transducer, and is co-planar with the ABS when a predetermined amount of optical power is applied to the near field transducer. A portion of the slider surrounding the distal end forms a concave surface having a continuously varying slope when no optical power is applied to the near field transducer, and a flat surface coplanar with the ABS and the distal end of the near field transducer when the predetermined amount of optical power is applied to the near field transducer.
It is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:
FIG. 1 is a schematic diagram illustrating an exemplary EAMR head comprising a slider and a near field transducer according to one aspect of the subject technology;
FIG. 2 is a graph showing a simulated trace of a heat-induced protrusion according to one aspect of the subject technology;
FIG. 3 is a flowchart illustrating an exemplary iterative heat-and-remove process for producing an EAMR head according to one aspect of the subject technology;
FIG. 4A is a cross-sectional views of a slider having a NFT modified by an iterative heat-and-remove process according to one aspect of the subject technology when no optical power is applied to the NFT; and
FIG. 4B is a cross-sectional views of a slider having a NFT modified by an iterative heat-and-remove process according to one aspect of the subject technology when an operational optical power is applied to the NFT.
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description, numerous specific details are set forth to provide a full understanding of the present invention. It will be apparent, however, to one ordinarily skilled in the art that the present invention may be practiced without some of these specific details. In other instances, well-known structures and techniques have not been shown in detail to avoid unnecessarily obscuring the present invention. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or designs.
FIG. 1 is a schematic diagram illustrating an exemplary EAMR head 100 comprising a slider 101 and a near field transducer 158 according to one aspect of the subject technology. The slider 101 comprises a substrate 110 , a recorder/reader layer 120 disposed over the substrate 110 , and an overcoat layer 130 disposed over the recorder/reader layer 120 . In the illustrated example, the substrate 110 comprises AlTiC and the overcoat layer 130 comprises alumina. The slider 101 has a leading edge 107 and a trailing edge 109 , and an air-bearing surface (ABS) 105 facing a magnetic recording medium 103 . The recorder/reader layer 120 of the slider 101 includes a writer 122 for recording or erasing information on the medium 103 by focusing a magnetic field on a spot on the medium 103 , a coil 124 for generating the magnetic field, a reader 126 for reading a magnetic bit recorded on the medium 103 , and a waveguide structure 150 . The waveguide structure 150 is configured to couple incident laser beam 171 from a laser diode 102 into a waveguide core layer 154 disposed in the coupler 150 . The waveguide structure 150 includes a first clad layer 152 and a second clad layer 156 surrounding the waveguide core layer 154 . Disposed at an interface between the second clad layer 156 and the waveguide core layer 154 is a grating 128 having a period and a depth selected to couple incident laser beam 171 into waveguide core layer 154 . The waveguide structure 150 further includes a near field transducer (NFT) 158 formed at a distal end of the waveguide structure 150 proximate the ABS 109 . The NFT 158 is configured to concentrate energy from the laser beam to a nano-sized spot on the recording medium 103 well below the so-called “diffraction limit” imposed on standard focusing lenses. The NFT 158 is typically formed of a metal such as gold (Au), silver (Ag), aluminum (Al), copper (Cu), or a combination (alloy) thereof.
The EAMR head 100 can also includes a laser diode 102 configured to generate a laser beam in response to an electrical power applied thereto. In certain embodiments, the laser diode is affixed to the slider 101 . In some embodiments, the laser diode can be a vertical-cavity-surface-emitting laser (VCSEL). In other embodiments, the laser diode 102 can be a separate structure disposed at a certain distance from the slider 101 and transmitting light to the waveguide structure 150 via an airgap.
During the operation of a hard disk drive comprising the EAMR head 100 , the magnetic recording medium 103 rotates at high speed, and air flowing at high speed between the ABS 105 and the magnetic recording medium 103 provides an upward force to the slider 101 such that the slider 101 is maintained at a certain height from the magnetic recording medium 103 . A portion of the incident laser beam 171 emitted by the laser diode 102 and arrived at the waveguide structure 150 is coupled into the waveguide core layer 154 by means of the grating 128 to form a coupled laser beam 172 traveling down the waveguide core layer 154 toward the ABS 105 . The coupled laser beam 172 is concentrated onto a nano-sized spot on recording medium 103 by means of the NFT 158 . The nano-sized heated spot on the magnetic medium 103 is subsequently subjected to a pulse of write magnetic field from the writer 122 .
Viewed from the perspective of a power flow, a portion of an electrical energy provided to the laser diode 102 is converted into an incident optical power by the laser diode 102 in the form of the incident laser beam 171 . A portion of the incident optical power is coupled into the waveguide core layer 154 as a coupled optical power in the form of the coupled laser beam 172 . A portion of the coupled optical power is transmitted to the magnetic recording medium 103 as near field radiation 173 , which is absorbed by a nano-sized spot on the magnetic recording medium 103 to generate heat therein.
Typically, an optical conversion efficiency of the NFT 158 —the percentage of the coupled optical power converted into the focused optical power using the above-defined terminologies—is in the range of 1-10%. A portion of the coupled optical power not converted into the focused optical power generates heat at the NFT and a surrounding region. The heat at NFT 158 and the surrounding portion of the slider may cause the region to protrude above the ABS 105 . FIG. 2 is a graph showing a simulated trace 201 of such a heat-induced protrusion as a function of a distance measured from the left edge of the substrate 110 ( FIG. 1 ), with the + direction being towards the trailing edge 109 of the slider 101 . The trace 201 shows a sharp protrusion at a region comprising the NFT and a portion of the slider surrounding the NFT, with its peak occurring at the center of the NFT. This simulation is performed with the assumption that 20 mW of optical power is applied to a volume of 273 nm×180 nm×100 nm at the write gap (WG). It can be seen that the protrusion is very localized due to the small size of the heat source. In the simulation embodiment, the maximum protrusion beyond the ABS is seen to be 50 nm at 20 mW. Even if the optical power is reduced by half, e.g., to 10 mW, the NFT protrusion above the ABS is still in the range of 20-30 nm. Considering that the slider can float at a height in the range of few nanometers above the magnetic recording medium, such a heat-induced NFT protrusion may result in the chipping or cracking of the NFT and damage to the recording media.
To reduce or eliminate such a heat-induced NFT protrusion, a fabrication process of the EAMR head can be configured to modify a shape of a region of the ABS surrounding the NFT to compensate for the heat-induced NFT protrusion, according to one aspect of the subject technology. In particular, the process can involve iteratively applying increasingly larger levels of optical power to the NFT, thereby generating heat in the NFT and the surrounding region, and removing a corresponding heat-induced protrusion at the NFT and the surrounding slider portion. FIG. 3 is a flowchart illustrating an exemplary iterative heat-and-remove process 300 for producing an EAMR head. The iterative heat-and-remove process 300 begins at state 310 and proceeds to a state 320 , in which a first level of optical power (P opt ) is applied to the NFT. As explained above, the optical power is delivered to the NFT in the form of a laser light (e.g., the coupled laser beam 172 of FIG. 1 ), and the optical power generates heat in the NFT and a surrounding portion of the slider. The laser light and its associated optical power can be coupled from a laser source (either affixed to the slider or separate) into a waveguide (e.g., the waveguide structure 150 of FIG. 1 ) formed in the EAMR head and directed to the NFT. Alternatively, the laser light can be applied directly to the NFT from an external laser source during the fabrication process. Regardless of the chosen channel, the first level of optical power carried by the laser light generates heat at the NFT, which heat, in turn, induces a first localized protrusion in a region comprising the NFT and the surrounding slider portion as described above.
The process 300 proceeds to a state 330 , in which the first localized protrusion is removed by, e.g., a bar lapping process. In one embodiment, the bar lapping process is a chemical-mechanical polishing (CMP) process. In certain embodiments, the removal process is performed while a constant optical power is applied to the NFT. In other embodiments, the optical power is increasing while the removal process is in progress. In yet other embodiments, the optical power is temporarily turned off during the removal process. The process 300 proceeds to a decision state 340 , in which a query is made as to whether P opt has reached a preset final optical power. In certain embodiments, the preset final optical power corresponds to an operational level of optical power for use during a recording operation of the EAMR head. In other embodiments, the preset final optical power can be a level of optical power different from the operational level due to the need to compensate for a thermal variation caused by the removal process or due to the fact that the optical power is being delivered by an external laser source during the fabrication process in which case the optical power required to produce the same amount of heat at the NFT may be different from the operational optical power delivered via the waveguide structure.
If the answer to the query at the decision state 340 is YES, the process 300 ends at state 390 . On the other hand, if the answer is NO, the process 300 continues at a state 350 , in which the optical power is increased to a next level, and then proceeds to the state 320 , in which the next level of optical power is applied to the NFT. The next level of optical power generates a next level of heat at the NFT, which heat, in turn, induces a next localized protrusion in the region comprising the NFT and the surrounding slider portion. The next localized protrusion is removed at the state 330 . The heat-and-remove process of the states 320 , 330 , 340 , and 350 is repeated until the optical power has reached a preset final optical power.
It shall be appreciated that many variations to the iterative heat-and-remove process 300 described above are possible without departing from the scope of the present disclosure. For example, in those embodiments in which a constant or increasing optical power is applied during the removal process, the states 320 and 330 may be combined into a single state, in which the localized protrusion is removed while the constant or increasing optical power is applied to the NFT. In the latter case in which the optical power is increased during the removal process, the state 350 may not be performed as a separate step. The iterative heat-and-remove process 300 described above is terminated when the optical power reaches a preset final optical power. For example, according to one aspect of the subject technology, the process may complete after a preset number of steps (e.g., 10 of 2 mw increments for an exemplary final optical power of 20 mw). Alternatively, the process may be terminated after a certain other condition is satisfied. For example, the temperature of the ABS near the NFT can be measured by a contact or remote measurement method, and the process can be terminated when the measured temperature reaches a preset final temperature.
An iterative heat-and-remove process such as the one described above with respect to FIG. 3 is superior to a single (non-iterative) heat-and-remove process in which a preset maximum optical power is applied to the NFT and the corresponding heat-induced protrusion is removed in a single step, because such a single heat-and-remove process can lead to an abrupt breakage in the NFT protrusion and cause an attendant damage to the NFT during the removal process. By iteratively applying increased levels of heat to the NFT and removing corresponding incremental protrusions, the iterative heat-and-remove method described herein can prevent breakage of the NFT and also produces a smooth surrounding concave surface in the slider at the end of the removal process. FIGS. 4A and 4B are cross-sectional views of a slider 401 having a near field transducer (NFT) 410 modified by an iterative heat-and-remove process such as the one described above. FIG. 4A corresponds to a case in which no optical power is applied to the NFT 410 , and FIG. 4B corresponds to a case in which an operational optical power (e.g., the optical power to be used during a recording operation) is applied to the NFT 410 . The shown section of the slider 401 has an ABS 405 . The NFT 410 has a distal end 412 proximate the ABS 405 . The distal end 412 of the NFT 410 is recessed from the ABS 405 when no optical power is applied to the NFT 410 as shown in FIG. 4A , and is co-planar with the ABS 405 when a predetermined amount of optical power (e.g., an operational optical power) is applied to the NFT 410 as shown in FIG. 4B . A portion of the slider 401 surrounding the distal end 412 of the NFT 410 forms a concave surface 430 A having a continuously varying slope when no optical power is applied to the NFT 410 as shown in FIG. 4A , and a substantially flat surface 430 B coplanar with the ABS 405 and the distal end 412 of the NFT 410 when the predetermined optical power is applied to the NFT 410 . As shown in FIG. 4A , for example, there is a smooth transition from the ABS 405 to the concave surface 430 A without a sharp edge such as a 90-degree bend. Similarly, there is a smooth transition from the concave side surface to the bottom of the recess without a sharp edge such as a 90-degree bend. Put another way, a region 407 comprising the concave surface 430 A and its surrounding ABS portion has a continuously-varying slope (e.g., continuously differentiable without a discontinuity).
A recess having such a smooth surface with a continuously-varying slope caused by the iterative heat-and-remove process described herein has several advantages over a recess having sharp 90-degree edges at the top and bottom of the recess. For example, the smooth surface reduces the risk of having debris particles stuck in the recess after the fabrication and causing aberrations (e.g., absorption, attenuation, diffraction, divergence) in the focused laser beam pattern. In addition, as FIG. 4B illustrates, the smoothed-surface recess turns into a flat surface co-planar with the ABS 405 and the distal end 412 of the NFT 410 when an operational optical power is applied to the NFT 410 . In contrast, a recess having 90-degree edges at the top and bottom when no optical power is applied turns into an irregular surface not coplanar with the ABS and the NFT when an operational optical power is applied to the NFT. Such a non-coplanar surface can produce a portion of the slider slightly protruding beyond the ABS or the distal end of the NFT slightly below the ABS with the attendant degradation in the focusing ability of the NFT.
The description of the invention is provided to enable any person skilled in the art to practice the various embodiments described herein. While the present invention has been particularly described with reference to the various figures and embodiments, it should be understood that these are for illustration purposes only and should not be taken as limiting the scope of the invention.
There may be many other ways to implement the invention. Various functions and elements described herein may be partitioned differently from those shown without departing from the spirit and scope of the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and generic principles defined herein may be applied to other embodiments. Thus, many changes and modifications may be made to the invention, by one having ordinary skill in the art, without departing from the spirit and scope of the invention.
A reference to an element in the singular is not intended to mean “one and only one” unless specifically stated, but rather “one or more.” The term “some” refers to one or more. Underlined and/or italicized headings and subheadings are used for convenience only, do not limit the invention, and are not referred to in connection with the interpretation of the description of the invention. All structural and functional equivalents to the elements of the various embodiments of the invention described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and intended to be encompassed by the invention. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the above description. | 4y
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This invention relates generally to a novel superconducting material of metal oxides and, more specifically, to a superconducting material containing, as metal components, Pb, Sr, Ba, Y or a rare earth element, Ca and Cu. The present invention is also directed to a method of producing such a superconducting material.
As Pb-containing, copper oxide-type superconducting materials, Pb 2 Sr 2 (Y, Ca)Cu 3 O w (hereinafter referred to as 2213-phase), PbSrBa(Y, Ca)Cu 3 O W (hereinafter referred to as 1213-phase) and (Pb, Sr)Sr 2 (Y, Ca)Cu 2 O w (hereinafter referred to as 1212-phase) are known in the art (Cava, R. J. et al, Nature, 363, 211-214 (1988); Syono et al, Nikkei Chodendo, pp 4-5 (Jan. 1990); and Rouillon, T. et al, Physica C, 159, 201-209(1989)). The 2213- and 1213-phase superconducting materials which have a superconducting transition temperature Tc of about 50-70 K are considered to contain copper in both monovalent and divalent states. Thus, it is necessary to produce the 2213- and 1213 crystallographic phases in the atmosphere of a reducing gas so that both monovalent and divalent coppers may coexist. The 1212 phase superconducting material has a high Tc of about 100 K. The production of the 1212 crystallographic phase should be performed in a vacuum sealed quartz tube. Therefore, it is very difficult to practically utilize these materials for the production of superconducting articles such as a cable, since they require large, specific reaction apparatuses. It is reported that (Pb, Cu)Sr 2 YCu 2 O w which is a 1212 phase does not exhibit superconductivity (Sunshine, S. A. et al, Chemistry of Materials, 1, 331-335(1989).
A YBa 2 Cu 3 Oy (hereinafter referred to as 123-phase) superconductor which is the typical example of Pb-free copper oxide superconducting materials is known to have Tc of about 90 K. The 123 phase, however, has a problem because Tc thereof varies with the oxygen content thereof.
The present invention has been made with the foregoing problems of the known Pb-containing, metal oxide superconducting materials in view.
In accordance with one aspect of the present invention, there is provided a superconducting material comprising oxides of metals, said metals having the following composition:
(Pb.sub.1-z Cu.sub.z)(Sr.sub.1-y Ba.sub.y).sub.1-v Ca.sub.v).sub.2 (A.sub.1-x Ca.sub.x)Cu.sub.2
wherein A is at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Ho, Er, Yb and mixtures of at least one of Y, La, Nd, Sm, Eu, Gd, Ho, Er and Yb with at least one of Tb, Tm and Lu, x is a number not smaller than 0 but not greater than 0.4, v is a number not smaller than 0 but not greater than 0.2x, y is a number not smaller than 0.1 but is smaller than 0.7 and z is a number not smaller than (2y-0.4) but not greater than (2y+0.2) with the proviso that when x is smaller than 0.2 z is not smaller than (0.6-x) but smaller than 1.0 and when x is between 0.2 and 0.4 z is not smaller than 0.4 but is smaller than 1.0. In other words, x, y, v and z are numbers satisfying the following conditions:
0≦x≦0.4,
0.1≦y<0.7,
0≦v≦0.2x, and
2y-0.4≦z≦2y+0.2
with the proviso that 0.6-x≦z<1.0 when 0≦x≦0.2 and that 0.4≦z<1.0 when 0.2≦x≦0.4.
It is preferred that x, y, v and z be numbers satisfying the following conditions for reasons of providing a high Tc:
0≦x≦0.4;
0.4-0.5x≦y≦0.6 and 0.7-x≦z<1.0
when 0≦x≦0.2;
0.3≦y≦0.6 and 0.5≦z<1.0
when 0.2≦x≦0.4; and
2y-0.4≦z<1.0.
In another aspect, the present invention provides a method of producing the above superconducting material, comprising the steps of:
providing a blend of compounds of the metals in said metal oxides; and
heating said blend at an oxygen partial pressure P of at least 0.001 atm and a temperature within the range of from (860+40logP) ° C. to (1060+40logP) ° C. where P is the oxygen partial pressure in terms of atm.
Preferably, the heating step is performed at an oxygen partial pressure P of 0.1 to 1 atm and a temperature within the range of from (950+40logP) ° C. to (1050+40logP) ° C.
Since the superconducting material according to the present invention can be produced in an oxidizing atmosphere, it is possible to obtain an elongated superconducting article such as a cable without using specific reaction conditions or apparatuses. Further, the superconducting material of this invention has a high Tc and has such a dense structure as to provide a high superconductive critical current density. Moreover, the superconducting material can be produced in various methods using gas phase, liquid phase or solid phase reactions. With a gas phase method, such as sputtering, vacuum evaporation or CVD, epitaxial growth is accelerated and the superconducting film as produced exhibits satisfactory characteristics. With a liquid phase method, such as coprecipitation, evaporation to dryness, sol-gel method or fusion quenching, too, the superconducting phase as produced exhibits satisfactory superconducting characteristics. When the superconducting material of this invention is processed to form a cable by wire drawing after being filled in a sheath, a post treatment for intentionally increasing the oxygen content may be omitted. In addition, the superconducting material of a Pb-system according to the present invention can be easily prepared at relatively low costs.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described in detail below with reference to the accompanying drawings in which the sole FIGURE is X-ray diffraction patterns of Sample Nos. 14-19 obtained in Example 1.
DETAILED DESCRIPTION OF THE INVENTION
The superconducting material according to the present invention has a crystallographic phase which is similar to that of known (Pb, Cu)Sr 2 YCu 2 O w but which differs from the known 1212 phase in that portions of Sr and Y are substituted with Ba and Ca, respectively, in the superconducting material of the present invention. In the superconducting material of this invention the amount and disposition of oxygen are not critical. Generally, w is a number in the range of between 6.9 and 7.0.
It has been found that when the known 1212 phase is prepared in an oxidizing atmosphere, superconductivity is not observed. The X-ray diffraction analysis has revealed that when (Pb, Sr)Sr 2 (Y, Ca)Cu 2 O w is prepared in an oxidizing atmosphere Sr does not exist in the same site with that of Pb and that when (Pb, Cu)Sr 2 (Y, Ca)Cu 2 O w is prepared in an oxidizing atmosphere Ca is not completely dissolved into the Y site with a Pb/Cu ratio of 1:1. This fact, when taken in conjunction with the fact that the known, superconducting 1212 phase is prepared in a vacuum sealed reactor, suggests that the vacuum sealing is essential for the production of the known (Pb, Cu)Sr 2 (Y, Ca)Cu 2 O w superconducting material.
In contrast, the (Pb, Cu)(Sr, Ba, Ca) 2 (A, Ca)Cu 2 O w superconducting material of this invention can be produced by a heat treatment in an oxidizing atmosphere. The X-ray diffraction analysis has revealed that the presence of Ba permits Ca to form solid solution. The superconductivity in the material of this invention is considered to be ascribed to the sufficient dissolution of divalent Ca ion into trivalent A ion (Y or a rare earth element), which results in the introduction of a sufficient amount of holes to show superconductivity.
It is considered that the Ba substitution can form an ion disposition in the vicinity of A ion (Y or a rare earth element) similar to that of YBa 2 CuO 3 O w (Jirak, Z. et al, Physica C 156, 750-754(1988) so that Ca can be dissolved into the Y site.
The superconducting material of the present invention may be produced by a method including providing a blend of compounds of the metals in the metal oxide superconducting material. The blend is in the form of a solid and may be obtained by a method including mixing powders of metal compounds, a method including applying a solution containing the metal compounds onto a substrate, followed by drying or a method including subjecting a solution containing the metal compounds to coprecipitation conditions. Other methods such as spattering, vacuum evaporation, CVD, fusion quenching or sol-gel may be also used. The solid blend is then heated at an oxygen partial pressure P of at least 0.001 atm and a temperature of between (860+40logP) ° C. and (1060+40logP) ° C. where P is the oxygen partial pressure in terms of atm.
The following examples will further illustrate the present invention.
EXAMPLE 1
Powders of PbO, SrCO 3 , BaCO 3 , Y 2 O 3 , CaCO 3 and CuO were mixed in molar proportions so that blends having the following chemical compositions were obtained:
(Pb.sub.1-z Cu.sub.z)((Sr.sub.1-y Ba.sub.y).sub.1-v Ca.sub.v).sub.2 (A.sub.1-x Ca.sub.x)Cu.sub.2
in which x, y, v and z are numbers as shown in Table 1. Each of the blends was pressure molded to form a parallelepiped bar and the bar was sintered at 1000° C. for 1 hour in an oxygen stream at 1 atmosphere. The resulting products were tested for their X-ray diffraction patterns and superconductivity and the results were as summarized in Table 1. In Table 1, T ON is a temperature (K) at which the resistivity abruptly begins decreasing and T R=0 is a temperature (K) at which the resistivity becomes 0. In Table 1, the term "1212 phase" refers to the crystallographic phase similar to that of the known (Pb, Sr)Sr 2 (Y, Ca)Cu 2 O w superconducting material. Samples Nos. 1, 3, 4, 8, 9, 14, 19, 20, 23, 29, 30, 32, 38, 39, 41 and 44 are comparative samples.
From these results, it is seen that when Ba is not present (y=0), no superconductivity is exhibited. Superconductivity is observed when Ba is present. With the increase in Ba content, Tc becomes higher but an impurity phase (BaPbO 3 ) is formed. This impurity phase disappears, without encountering a reduction of Tc, when the amount of Cu is increased (when z is increased). Even with a high Cu content, however, the impurity phase occurs when y is increased to 0.7. When x is 0 and y is 0.5, Tc increases with the increase in Pb content (with the decrease in z). This suggests that even a small amount of Pb serves to reduce non-stoichiometry of oxygen to the extent that no specific post treatment is necessitated.
EXAMPLE 2
Powders of PbO, SrCO 3 , BaCO 3 , A 2 O 3 (or A 6 O 11 or AO 2 ), CaCO 3 and CuO were mixed in molar proportions so that blends having the following chemical compositions were obtained:
(Pb.sub.1-z Cu.sub.z)(Sr.sub.1-y Ba.sub.y).sub.2 (A.sub.1-x Ca.sub.x)Cu.sub.2
in which x, y and z are 0.4, 0.5 and 0.7, respectively. As the element A, Y and the rare earth elements as shown in Table 2 were used. Each of the blends was pressure molded to form a bar and the bar was sintered at 1000° C. for 1 hour in an oxygen stream at 1 atmosphere. The resulting products were tested for their X-ray diffraction patterns and superconductivity and the results were as summarized in Table 2. From the results shown in Table 2, it is seen that the use of Ce or Pr which is generally tetravalent fails to produce superconductivity. Except for La, Tc is increased with the decrease of the ion radius. This also applies to the case in which two or more elements are used in combination, when the average ion radius of the combined elements is taken into account.
EXAMPLE 3
Powders of PbO, SrCO 3 , BaCO 3 , Y 2 O 3 , CaCO 3 and CuO were mixed in molar proportions so that a blend having the following chemical compositions was obtained:
(Pb.sub.1-z Cu.sub.z)(Sr.sub.1-y Ba.sub.y).sub.2 (Y.sub.1-x Ca.sub.x)Cu.sub.2
in which x, y and z are 0.4, 0.5 and 0.7, respectively. Portions of the blend were pressure molded to form bars and the bars were sintered at a temperature and under a partial pressure of oxygen as shown in Table 3. The resulting products were tested for their X-ray diffraction patterns and superconductivity and the results were as summarized in Table 3. From the results shown in Table 3, it will be noted that an oxygen partial pressure of at least 0.001 atm is necessary to obtain the 1212 phase. When the oxygen partial pressure is lower than 0.001, there is formed 2213 phase. Further, it is seen that Sample Nos. 69, 70, 73, 74 and 77 which were produced at a temperature outside of the (860+40logP) ° C. to (1060+40 logP) ° C. range do not exhibit superconductivity.
EXAMPLE 4
Powders of PbO, SrCO 3 , BaCO 3 , Y 2 O 3 , CaCO 3 and CuO were mixed in molar proportions so that a blend having the following chemical compositions was obtained:
(Pb.sub.1-z Cu.sub.z)(Sr.sub.1-y Ba.sub.y .sub.2 (Y.sub.1-x Ca.sub.x)Cu.sub.2
in which x, y and z are 0.4, 0.5 and 0.7, respectively. Portions of the blend were subjected to thermal analysis. Other portions of the blend were pressure molded and sintered at a temperature and under a partial pressure of oxygen as shown in Table 4. The resulting products were subjected to porosity measurement and superconducting critical current density measurement to obtain the results summarized in Table 4. From the results shown in Table 4, it will be understood that the superconducting critical current density of samples obtained by using a heat treatment temperature higher than the just-below temperature of the heat absorption peak is higher than that obtained at heat treatment temperature lower than the just-below temperature. The just-below temperature is a temperature at which part of the components of the sample is fused. The above fact, when considered in the light of the porosity values, suggests that the heat treatment at a temperature causing partial fusion of the components of the sample can make the sample more dense so that the effective cross-sectional area in which the electrical current flows is increased.
EXAMPLE 5
Powders of PbO, SrCO 3 , BaCO 3 , Y 2 O 3 , CaCO 3 and CuO were mixed in molar proportions so that a blend having the following chemical compositions was obtained:
(Pb.sub.1-z Cu.sub.z)(Sr.sub.1-y Ba.sub.y).sub.2 (Y.sub.1-x Ca.sub.x)Cu.sub.2
in which x, y and z are 0.4, 0.t and 0.7, respectively. Portions of the blend were pressure molded and sintered at 1000 ° C. in an oxygen stream. The resulting products were then post-treated under various conditions as shown in Table 5 to obtain products whose Tc were as shown in Table 5. From the results summarized in Table 5, it is seen that the post treatment at a high oxygen partial pressure can produce superconducting materials with a high Tc. Such a post treatment, though it is not essential in the present invention, can improve T ON .
TABLE 1______________________________________SampleNo. v x y z Crystal Phase T.sub.ON T.sub.R=0______________________________________1** 0 0 0.2 0.5 (1212) -- --2 0 0 0.2 0.6 (1212) 12 --3** 0 0 0.2 0.7 (1212) + SrCuO.sub.2 11*4** 0 0 0.3 0.5 (1212) -- --5 0 0 0.3 0.6 (1212) 19 --6 0 0 0.3 0.7 (1212) 22 127 0 0 0.3 0.8 (1212) 30 198** 0 0 0.3 0.9 (1212) + SrCuO.sub.2 32* 12*9** 0 0 0.4 0.5 (1212) -- --10 0 0 0.4 0.6 (1212) 25 1211 0 0 0.4 0.7 (1212) 40 2712 0 0 0.4 0.8 (1212) 46 3713 0 0 0.4 0.9 (1212) 54 3914** 0 0 0.5 0.5 (1212) -- --15 0 0 0.5 0.6 (1212) 32 2016 0 0 0.5 0.7 (1212) 57 4217 0 0 0.5 0.8 (1212) 76 6818 0 0 0.5 0.9 (1212) 74 6719** 0 0 0.5 1.0 (1212) 72 5820** 0 0 0.6 0.7 (1212) + BaPbO.sub.3 60* 37*21 0 0 0.6 0.8 (1212) 77 6822 0 0 0.6 0.9 (1212) 75 6523** 0 0 0.7 0.9 (1212) + BaPbO.sub.3 75* 58*24 0 0.2 0.2 0.4 (1212) 33 1825 0 0.2 0.2 0.6 (1212) 46 2926 0 0.2 0.4 0.4 (1212) 48 3527 0 0.2 0.4 0.6 (1212) 58 4828 0 0.2 0.4 0.8 (1212) 72 5929** 0 0.2 0.4 1.0 (1212) 70 5830** 0 0.2 0.6 0.6 (1212) + BaPbO.sub.3 45* 29*31 0 0.2 0.6 0.8 (1212) 80 7132** 0 0.2 0.6 1.0 (1212) 77 6633 0 0.4 0.2 0.4 (1212) 28 1034 0 0.4 0.2 0.6 (1212) 46 2135 0 0.4 0.4 0.4 (1212) 35 1936 0 0.4 0.4 0.6 (1212) 70 5337 0 0.4 0.4 0.8 (1212) 83 7238** 0 0.4 0.4 1.0 (1212) 77 6239** 0 0.4 0.6 0.6 (1212) + BaPbO.sub.3 80* 45*40 0 0.4 0.6 0.8 (1212) 83 7441** 0 0.4 0.6 1.0 (1212) 75 6542 0.4 0.4 0.4 0.6 (1212) 73 6043 0.8 0.4 0.4 0.6 (1212) 74 6344** 0.12 0.4 0.4 0.6 (1212) + 68* 58* (Sr,Ca)CuO.sub.2______________________________________ *: Tc of (1212) phase only (analyzed by the EDX method **: comparative sample
TABLE 2______________________________________Sample No. Element A Crystal Phase T.sub.ON T.sub.R=0______________________________________45 La (1212) 61 39 46** Ce unconfirmed phase -- -- 47** Pr unconfirmed phase -- --48 Nd (1212) 53 3049 Sm (1212) 54 3250 Eu (1212) 56 3651 Gd (1212) 70 4652 Dy (1212) 77 5653 Ho (1212) 77 6054 Er (1212) 80 5055 Yb (1212) 78 5556 Y.sub.0.5 Ce.sub.0.5 (1212) + Unconfirmed 58 2257 Y.sub.0.5 Pr.sub.0.5 (1212) + Unconfirmed 44 2258 Y.sub.0.5 Eu.sub.0.5 (1212) 60 2159 Y.sub.0.5 Ho.sub.0.5 (1212) 81 4260 Y.sub.0.5 Yb.sub.0.5 (1212) 80 6261 La.sub.0.5 Eu.sub.0.5 (1212) 47 6762 La.sub.0.5 Ho.sub.0.5 (1212) 52 1963 La.sub.0.5 Yb.sub.0.5 (1212) 55 36______________________________________ **: comparative sample
TABLE 3______________________________________ Oxygen Partial Temper-Sample Pressure atureNo. (atm) (°C.) Crystal Phase T.sub.ON T.sub.R=0______________________________________64** 0.0001 800 (2213) + Impurity -- --65** 0.0001 840 (2213) + Impurity -- --66** 0.0001 880 Melted -- --67 0.001 800 (1212) 56 3168 0.001 880 (1212) 60 3869** 0.001 960 Melted -- --70** 0.1 800 Impurity -- --71 0.1 880 (1212) 65 4472 0.1 960 (1212) 70 5773** 0.1 1040 Melted -- --74** 10 880 Impurity -- --75 10 960 (1212) 72 6076 10 1040 (1212) 83 7577** 10 1120 Melted -- --______________________________________ **: comparative samples
TABLE 4__________________________________________________________________________Heat Treatment Heat AbsorptionOxygen Peak Temperature CriticalPartial Temper- Just Melting CurrentSamplePressure ature Below Point Porosity DensityNo. (atm) (°C.) (°C.) (°C.) (%) (A/cm.sup.2)__________________________________________________________________________78 0.1 * 967 985 -- --79** 0.1 940 -- -- 17 13080** 0.1 960 -- -- 16 26081 0.1 970 -- -- 8 160082 0.1 980 -- -- 5 202083 10 * 1021 1044 -- --84** 10 960 -- -- 20 21085** 10 980 -- -- 18 38086** 10 1000 -- -- 17 39087 10 1020 -- -- 8 107088 10 1030 -- -- 3 255089 10 1040 -- -- 3 2990__________________________________________________________________________ *: thermoanalysis **: comparative sample
TABLE 5______________________________________Post TreatmentSample Oxygen partial Temperature TimeNo. Pressure (atm) (°C.) (hour) T.sub.ON T.sub.R=0______________________________________90 0.1 500 5 81 6891 0.1 500 50 83 7492 1 500 5 83 7293 10 500 5 84 7494 400 500 5 83 7595 400 900 5 83 76______________________________________ | 4y
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The present invention relates to a method and apparatus for harness making wherein the electrical conductor wires which form the harness are caused to be affixed to a wire retainer with a segment of each wire locked to such retainer with the retainer made to engage a frame which is grooved in a pattern to define a wiring harness. The frame is a structural member of an apparatus served by the harness and is made to contain apertures into which are fitted various components. The wire retainer may be an electrical connector or, alternatively, a simple plastic housing mechanically attached to the wire segments. The invention method embraces rolling as a method of wire implantation, with the roller being made to drive the frame in relative movement so that wire rolling and frame movement are accommodated in a much simplified manner than with respect to the prior art.
BACKGROUND OF THE INVENTION
The use of wire rolling techniques to position wires on centers for subsequent termination to handle twisted pair wires in respect to bulk cable is taught in a number of U.S. Patents including U.S. Pat. Nos. 3,891,013 and 3,871,072. U.S. Pat. No. 4,076,365 also teaches the spreading of wire conductors for the purpose of location for termination wherein there are grooves provided in a connector housing into which conductor wires are driven. U.S. Pat. No. 4,132,251 teaches a similar concept but uses a tool which rolls the wires into grooves.
Pertinent also is U.S. Pat. No. 4,387,509 which deals with a method of manufacturing an electrical interconnection assembly wherein wires are laid in grooves in a substrate tool, with the wires being subsequently transferred from the grooved element to terminals carried by an insulating support to form the assembly.
In U.S. patent application Ser. No. 134,328 (Attorney Docket 13905) co-filed with the present application and assigned to the same assignee, there is taught the concept of using the rolling technique in conjunction with an element which is a structural member of the apparatus served by the harness made up of wires implanted in grooves in such structural element. In our copending application, the concept of using the structural element as a frame in conjunction with a tool having grooves which mate with grooves in the frame is taught in order to provide the ability to have free standing wires. The tool in that case is visualized as being mounted upon the wire laying jig upon which the frame is also mounted. There, rolling techniques are employed in conjunction with the loading of terminals and connectors and components, all related to an apparatus served by the structural element.
The present invention represents an improvement over the foregoing prior art in that it ensures an accurate and less costly technique of wire handling for harness making.
Accordingly, it is an object of the present invention to provide a novel method and apparatus for harness making which simplifies wire placement and lay-up. It is a further object to provide a novel and automation compatible technique and article which assists in the placement of wires into frames containing grooves and in conjunction with wire implantation. It is still a further object of the invention to provide wiring aides in the form of wire retainers and organizers which are compatible with existing wire handling equipment capable of measuring, cutting, stripping, and termination of multiple individual conductor wires. It is yet a further object to provide a method which simplifies the wire rolling mechanism in terms of size and cost, employing a novel method and frame apparatus.
SUMMARY OF THE INVENTION
The present invention teaches a method of forming electrical wiring harnesses by implanting electrical conductor wires into grooves laid out in a desirable to effect wire distribution. Such grooves are formed at least in part in elements which have a structural function relative to apparatus served by the wiring harness in one embodiment. In conjunction therewith, a wire organizer in the form of a simple plastic housing having wire retention means is taught, with a segment either at the ends or intermediate the ends of individual wires being captured and retained as a subassembly. The structural element is made to include surfaces which allow the wire retainer to be fitted therein with the grooves containing the segments of the wires in alignment with grooves in the structural element. This feature is taught in relation to the retainer being placed in an aperture in the frame element or alternatively, plugged into the end of the frame element. In one embodiment, the wire retainer is made to include preloaded terminals having insulation displacement slots therein to be terminated to the wires in such retainer connector. The structural element is made to contain other apertures adapted to receive components carrying slotted terminals therein to engage and terminate to the wires laid in the element. In accordance with the method of the invention, a roller is brought to bear against the wire retainer, with the wires therein thereafter being displaced into the grooves of the structural element by rotation of the roller which additionally displaces the structural element.
The wire implantation effected by the rolling action and the method of the invention can be implemented in accordance with the article of the invention at either end or in between the ends of the structural element, with movement in one direction effecting one sweep; or movement in more than one direction effecting more than one sweep by the roller over the surfaces of the wire organizer retainer, and the structural element.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end view of the rear of a vehicle containing a lamp assembly utilizing the present invention.
FIG. 2 is a view of the lamp assembly in plan with the protective lens cover removed to show an invention article.
FIG. 3 is a view similar to FIG. 2 but with components removed.
FIG. 4 is a plan view of a wire retainer having wires therein, the retainer having been removed from the assembly shown in FIGS. 2 and 3.
FIG. 5 is a plan view of an illustrative embodiment of a wire retainer.
FIG. 6 is a much enlarged perspective view showing an end of the wire retainer shown in FIGS. 2-5, with a slotted beam terminal positioned preparatory to termination of a wire laid in the wire retainer.
FIG. 7 is a view similar to that of FIG. 6, but showing the wire retainer loaded with terminals.
FIG. 8 is a view similar to that shown in FIGS. 6 and 7, but with the wire retainer loaded with terminals and a housing affixed thereto to insulate such terminals.
FIG. 9 is a schematic and side view showing a structural element mounted upon a jig preparatory to the loading of a wire retainer and wire therein.
FIG. 10 is a view similar to that of FIG. 9 but with the wire retainer in place and a wire implantation roller bearing against such retainer.
FIG. 11 is a view similar to FIG. 10 with the roller displaced to effect wire implantation.
FIG. 12 is a view of the structural element containing the wire with components added thereto.
FIG. 13 is a view similar to FIG. 12 with additional components attached thereto.
FIG. 14 is a view similar to that of FIG. 10 but employing an alternative method of roller operation.
FIG. 15 is a schematic and side view of an end of the wiring element in conjunction with the roller following the wire rolling operation.
FIG. 16 is a view of a wire retainer as applied in the mid span of various conductor wires.
FIG. 17 is a schematic and side view of the wire retainer and wire subassembly of FIG. 16 as applied to a structural element made to accommodate the retainer between the ends thereof and employed with two directions of relative movement between roller and wiring element.
FIG. 18 is a schematic and side view of an alternative embodiment of the article of the invention wherein the wire retainer is plugged into the end of the structural element.
FIG. 19 is a plan view of the wire retainer utilized with the showing in FIG. 18.
FIG. 20 is a schematic and side view of the elements of FIG. 18 and 19 in conjunction with the roller preparatory to wire implantation.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, there is shown a vehicle 10, the right-hand rearward portion thereof containing a lamp assembly 12 which serves the function of providing stop, turn and reverse signals for vehicle 10. The lamp assembly 12 is intended to typify a wide range of assemblies which contain components terminated to the wire harnesses in order to provide power and signal functions, such as home electrical appliances, automobile harness assemblies, and the like.
With reference to a specific embodiment as shown in FIG. 2, the assembly 12 includes a series of three lens structures 14, 16 and 18, beneath which structures are provided incandescent lamps powered to achieve the foregoing mentioned functions. The assembly includes a series of fasteners shown as 20 which lock the assembly together and to the vehicle body frame. FIG. 2 shows a part of the assembly heretobefore mentioned with the lens structures removed to reveal a frame 30 including apertures 32 intended to be engaged with the fastening means 20. To the left of the frame 30 as shown is a first aperture 34 which in this illustrative embodiment, is intended to accommodate the insertion of a wire organizer or retainer 38 which fits within such aperture. As can be seen in FIG. 2, a number of lamp assemblies 120 are mounted to frame 30, with each of the lamp assemblies 120 containing a plug-in lamp 122. A number of grooves 37 are provided in the upper surface of 30 extending from the aperture 34 across the face of 30 in a pattern to position conductor wires 100 so as to interconnect the various components. The assemblies 120 would include terminals similar to those to be described as elements 60 hereafter to follow.
FIG. 3 shows the components for 120 and lamps 122 removed to reveal apertures 35 in the frame element 30, with the wires 100 extending appropriately to permit termination to terminals of the components.
FIG. 4 shows the wire retainer 38 with terminals 60 removed and with the wires 100 positioned therein preparatory for wire layment. As can be discerned, the assembly represented in FIG. 4 is comprised simply of insulated wires 100 and a wire retainer 38. The wire retainer can be seen in additional detail in FIGS. 5 and 6 to be comprised of a body element or housing 39 containing at the ends thereof small projections 40 which, in conjunction with the shape of 39, serve to polarize or orient the retainer relative to mounting in the aperture 34 of the frame 30. The housing 39 includes additionally a series of apertures shown as 42 which may be considered to extend through the body 39 of the retainer. Adjacent each end of the apertures 42 are grooves shown as 44 which receive conductor wires positioned therein in the manner depicted in FIG. 4. Each of the grooves has a beveled wire entry surface shown as 48 and toward the center of the groove, projections shown as 50 and are better revealed in FIG. 6. These projections operate to capture and retain the wires inserted within the grooves in the manner indicated in FIGS. 5 and 6. In addition, included at each end of the housing 39 are projections shown as 52 which serve the function of orienting and locking terminal protecting housings 80 onto the retainers 39, to be described more fully herein.
In FIG. 6, the terminal much enlarged from actual size is shown as 60 to include a pair of contact springs 62 suitable formed to provide a funnel entry 63 adapted to receive contact tabs from a mating connector not shown. The terminal 60 includes a boxlike structure having at each end a slot 66 dimensioned to function in the well-known IDC manner to terminate wires such as 100 by stripping the outer sheath of insulation thereof and engaging the strands with sufficient resilient spring pressure to maintain a gas-tight termination over the life of the terminal. The slots 66 open into a beveled portion shown as 68 which tend to center the wire to aid in positioning and engagement with the slots. Terminals 60 include one or more lances shown as 74, dimensioned and positioned to engage the interior surfaces of the aperture walls 42 to lock the terminals to the housings 39 of wire retainer 38.
FIG. 7 shows the wire retainer 38 loaded with terminals 60 to terminate the wires 100 carried therewithin. FIG. 8 shows the loaded wire retainer having additionally a protective insulating housing positioned over the terminals, such housing being shown as 80 which is particularized for the several terminals with the spacing shown as 82 therebetween. Additionally, there is included a flange element shown as 84, apertured as at 85 to fit over the plastic post element 52 which is in a preferred embodiment, heat-staked as shown in FIG. 8 to lock the housing to the wire retainer. Power or signal wires connected to terminals not shown would be plugged into the various terminals 60 to provide inputs and outputs to the circuit.
In conjunction with the invention method and article, it is contemplated that the wire retainer 38 may be incorporated into a frame with the terminals 60 added thereafter. Alternatively, it is contemplated that the wire retainer may be utilized on wire handling equipment with the wires 100 cut and terminated and loaded into the wire retainer as shown in FIG. 4, with the terminals then added with or without a housing 80 which may be added following terminal insertion or at a later time. In this event, the wire retainer, as terminated, may be loaded into the aperture 34 of frame 30. As can be observed from FIGS. 2 or 3, the grooves in the wire retainer shown as 44 are aligned with the grooves 37 in the frame. By insertion of the wire retainer containing wire segments into the frame, the wire segments may be considered started to allow wire implantation into the grooves 37 by a number of means in accordance with the prior art. In the event that the terminals have been pre-applied to the wire retainer 38, it will be necessary to manually or through the use of a robotic assist insert a further segment of the wire just adjacent the wire retainer in the beginning segment of grooves 37 with the roller then applied to the surface of the frame adjacent such wire retainer. It is fully contemplated that the wire retainer may be used alone without terminals, as a wire organizer, and as a means to facilitate processing of subassemblies or with the terminals applied following wire insertion.
Referring now to FIG. 9, the frame 30 can be seen to be positioned upon a jig shown as 104 having a series of projections 106 which fit into the apertures 35 of the frame. These projections include in their upper surfaces, grooves 37' which match the grooves 37 in the frame 30. As shown in FIG. 9, a wire retaining element 38 is positioned above the frame 30 having the wires 100 captured therein. With regard to the showing in FIG. 9, the jig 104 may be considered to be fixed against displacement. In FIG. 10, the wire retainer 38 is shown inserted within the aperture 34 with portions of the wires 100 made to come up out of the grooves 44, with each wire aligned with an appropriate groove 37. There is provided in FIG. 10 a roller assembly shown as 110. The roller assembly 110 includes a pair of brackets 112 carrying therebetween a roller shown as 114 and a wire bail assembly shown as 116. It is to be understood that the bail 116 is readily opened to accommodate the insertion of the wires 100 in the manner shown in FIG. 10. It is to be further understood that the roller 114 is sufficiently elastic to deform to depress the wires well within the grooves 37. Reference may be had to our copending case for these details.
With the roller assembly 110 positioned as shown in FIG. 10 and bearing down upon the top of the wire retainer 38, it is then driven to the right as shown in FIG. 11 to force the wires 100 within the grooves 37, such wires tracking within the grooves 37' of the jig fixtures 106 as the roller moves over the apertures 35.
Following the movement shown in FIG. 11, the wires are now positioned in their patterns and in accordance with the invention, terminals 60 may be applied to terminate the wires in the manner shown in FIG. 12. Also at this particular point, component housings containing suitable IDC terminals may be applied such as lamp housings 120, also as shown in FIG. 12. Thereafter, as shown in FIG. 13, housings 80 may be secured to the wire retainer means as heretofore described and the bulbs or lamps 122 may be inserted in the lamp housings 120 using terminals not shown but similar to terminals 60. As thus shown in FIG. 13, the assembly is as was described relative to FIG. 2 and ready for application to the vehicle and the lamp assembly 12. Alternatively the unit could accept at this point switches, relays, timers, integrated circuit packages, and the like, depending upon the application of the frame. At this point in time, a suitable connector not shown will be plugged into the terminal 60 to make the unit functional. Alternatively, the unit shown in FIG. 13 may be tested for continuity and stacked or handled for loading during assembly of the vehicle on a production line.
FIG. 14 refers to an alternative method wherein the jig 104 is mounted for displacement while the roller assembly is relatively fixed against movement in an X and Y sense, there being a suitable mechanism to move roller assembly 110 vertically as indicated to bring it to bear against the top of the frame 30 and/or the wire retainer 38. As heretofore described relative to FIG. 9, the wire retainer containing wires 100 is first loaded into the top of the frame as positioned upon the jig 104. Next, in accordance with the invention, a drive not shown which could be manually effected is made to force the jig 104 to the left to a position as shown in FIG. 15, the roller traversing the upper surface of the frame 30 effecting wire layment into the grooves thereof.
It is contemplated that the wire rolling assembly 110 may be provided with a rotary drive by suitable means not shown, which in turn will track against the upper surface of frame 30, moving the frame and the jig 104 as the roller implants the wires 100 in such frame. As can be appreciated, this concept vastly simplifies the mechanism employed to utilize the rolling concept. Various jigs of appropriate height having appropriate means to lock frames thereupon may thus be employed with a roller or sets of rollers without the need for extensive closely toleranced spans of wire laying tracks and guides as heretofore required.
FIG. 16 shows an embodiment of the invention, article and concept wherein the wires 100 are loaded into the wire retainer 138 intermediate the ends of the wires rather than at the ends as heretofore described. In accordance with the concept of FIG. 16, a frame shown as 130 in FIG. 17 would be made to have an aperture 134 located intermediate the ends of the frame 130, with the retainer being first plugged in and the different ends of the wires 100 fed through an appropriate bail 116 on each side of the roller, with the roller of assembly 110 then being brought down to bear against the upper surface of 38 and either the jig 104 displaced or the roller actuated to effect the first wire layment in one direction followed by a wire layment in a second direction. This concept is particularly useful wherein the wires 100 are of different lengths and begin or end in a non-even location in a given frame member.
FIG. 18 shows an alternative embodiment of the invention wherein a frame shown as 130' is made to include a pair of recesses 131' at an end thereof. A wire retainer shown as 138' is made to include projections 140' which engage the apertures 131' and align the wire retainer 138' with the frame. The wire retainer 138' is otherwise similar to the wire retainer 138 heretofore discussed and works in a similar fashion except working from the end of the frame 130'. FIG. 20 shows a roller brought to bear against the upper surface of 138' preparatory to wire layment.
With respect to the FIGS. 14-20 and as heretofore mentioned, the wire retainer element may serve as a wire organizer without terminals or may serve as a connector having terminals. The invention contemplates both possibilities as well as the addition of terminals to the wire retainer element both before and after wire layment. It is also contemplated that more or less standard IDC connectors may be employed in conjunction with the invention, the frame being designed to accommodate such standard connectors fitted into apertures therein or plugged into end surfaces. Reference may be had to U.S. Pat. No. 4,159,158 and U.S. Pat. No. 4,435,035 wherein connectors suitable for such use are depicted.
In the disclosure heretofore given, the illustrative examples have included essentially a single wire retainer or wire retainer/connector in conjunction with a single structural member. It is contemplated that multiple wire retainers may be used with an individual structural member to achieve different wwiring patterns including on occasion, wiring patterns which have crossovers as is taught in our copending application 13905. It is also contemplated that multiple structural elements may be placed adjacent each other with multiple wiring retainers/connector attached thereto or plugged therein with wire rolling and layment taking place over the several individual elements.
Having now described the invention relative to drawings, we now set forth a definition of method and article in the appended claims. | 4y
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to eyeglasses and eye wear, and more specifically to a holder for eyeglasses that allows for convenient storage of a conventional pair of eyeglasses on both horizontal and vertical surfaces.
2. Description of the Related Art
Those of us who are required to wear corrective lenses are often faced with finding a safe place to put our eyeglasses during the periods when they are not being worn. Whether it be while sleeping, during activities that do not require their use, at the hair dresser or at the doctor's office, one places these expensive and delicate items at risk of suffering a variety of damage simply by setting them down. Eyeglasses are often knocked, kicked, stepped on, sat on and otherwise damaged in degrees ranging from scratched lenses and bent frames to complete ruin. Accordingly, there is a need for a means by which one can remove and store his or her eyeglasses in a safe manner while maintaining easy access to them. The development of the present invention fulfills this need by providing a device into which a conventional pair of eyeglasses can be placed and stored in a secure fashion.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention. However, several references to devices used to secure eyeglasses for a variety of purposes were discovered. These devices neither anticipate nor disclose any embodiment that would preclude the novelty and the utilitarian functionality of the features of the present invention.
U.S. Pat. No. 5,592,244, issued in the name of Vyhmeister, discloses a holding device for eyeglasses wherein a clamping device is fit with a suction cup. The clamp is used to secure a conventional pair of eyeglasses, allowing them to be suspended or otherwise secured to a surface.
U.S. Pat. No. 5,568,872, issued in the name of Hinnant, describes an eyeglass holder that allows a user to hang a conventional pair of eyeglasses therefrom, suspending them from the hinge portion between the eyeglass frame and stem. The holder is designed to be either free-standing or hung from an automobile rear view mirror.
U.S. Pat. No. 5,188,322, issued in the name of Kinstrey, describes an eyeglass holder wherein a padded cloth article is designed to be inserted in a conventional drinking mug or the like. Secured to the rim of the mug, the device allows for the placement of conventional eyeglasses therein for convenient storage and protecting them from damage.
U.S. Pat. No. 4,432,521, issued in the name of Douglas, describes an eyeglass cradle for storing conventional eyeglasses wherein a padded cloth article is suspended across the interior portion of a base frame consisting of a length of U-shaped channel material.
U.S. Pat. No. 4,584,633, issued in the name of Comfort, discloses an combination nightlight and eyeglass holder.
Other patents of general relation and not of any particular relevance, but warranting mention include the following:
U.S. Pat. No. 5,092,666, issued in the name of Cress;
U.S. Pat. No. 4,204,750, issued in the name of Hilbert;
U.S. Pat. No. 4,136,934, issued in the name of Seron;
U.S. Pat. No. 4,131,401, issued in the name of Bradley; and
U.S. Pat. No. 4,032,223, issued in the name of Bradley.
While several features exhibited within these references may be incorporated into this invention, alone and in combination with other elements, the present invention is sufficiently different so as to make it distinguishable over the prior art.
SUMMARY OF THE INVENTION
The present invention consists of an eyeglass holder wherein a storage frame, constructed of plastic, rubber, or other like formable materials, or a combination thereof, that allows for the placement therein of a conventional pair of eyeglasses for protection and storage. The semi-rigid, resilient frame secures the eyeglasses with a gravity induced friction fit, providing a protective shield for the lenses and absorbing the shock associated with falling, being crushed, sat upon or stepped on. Generally C-shaped in design that match the overall shape of conventional eyeglasses, the frame attaches to the eyeglasses on each stem and provides support at the nose piece located on the bridge. Fit with an optional suction cup type securing device, the eyeglass holder can be secured to smooth, horizontal and non-horizontal surfaces, such as automobile windshields, allowing for convenient access thereto.
It is therefore an object of the present invention to provide an eyeglass holder that will secure and support a conventional pair of eyeglasses, protecting them from damage caused by falls or contact with other objects.
It is another object of the present invention to provide an eyeglass holder that will secure and support a conventional pair of eyeglasses, storing them for convenient retrieval.
It is another object of the present invention to provide an eyeglass holder that will accept a variety of conventional eyeglass designs.
It is another object of the present invention to provide an eyeglass holder that provides friction fit securement of the eyeglass stems as well as a support for the eyeglass bridge nose piece.
It is another object of the present invention to provide an eyeglass holder that is constructed of lightweight, strong and durable materials such as plastic, rubber or other like formable materials, or a combination thereof.
It is another object of the present invention to provide an eyeglass holder that is of a simple design that is easy to produce, resulting in a cost-effective manufacture.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is a top view of the eyeglass holder, according to the preferred embodiment of the present invention;
FIG. 2 is a side view of the eyeglass holder, according to the preferred embodiment of the present invention;
FIG. 3 is a rear view of the eyeglass holder, according to the preferred embodiment of the present invention;
FIG. 4 is a top view of the eyeglass holder depicting its use in securing a pair of convention eyeglasses, according to the preferred embodiment of the present invention;
FIG. 5 is a side view of the eyeglass holder depicting its use in securing a pair of conventional eyeglasses, according to the preferred embodiment of the present invention.
LIST OF REFERENCE NUMBERS
10 Eyeglass Holder
11 Frame
12 Bridge Support
13 Stem Support
15 Stem Securing Clasp
16 Securing Tabs
17 Stem Receiving Cavity
20 Bridge Rest
25 Nose Rest Pads
26 Eyeglasses
27 Bridge Rest Mid-Section
28 Eyeglass Stems
30 Suction Cup
31 Mounting post
32 Suction Cup Securing Aperture
35 Eyeglass Lenses
DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Detailed Description of the Figures
Referring now to FIGS. 1-3, depicted is the eyeglass holder 10 according to the preferred embodiment of the present invention. The eyeglass holder 10 consists of a generally C-shaped frame 11 consisting of an elongated bridge support 12 terminated at each end by the proximal end 13a of a linearly elongated stem support 13. The stem supports 13 extend perpendicularly from the bridge support 12, parallel to one another. The general shape and contour of the frame 11 corresponds to that of a conventional pair of eyeglasses (not shown in FIGS. 1-3). An eyeglass stem securing clasp, hereinafter stem securing clasp 15, is located at the distal end 13b of each stem support 13. The stem securing clasps 15 consist of a pair of curved securing tabs 16 that are biased against one another by the resilient nature of the material used to construct the frame 11 such that the tips of the securing tabs 16 maintain a position in close proximity to one another and forming a stem receiving cavity 17 into which the stem of a conventional pair of eyeglasses (not shown in FIGS. 1-3) can be inserted and secured. A bridge rest 20 centered along the bridge support 12 on the inside portion of the C-shaped frame 11 allows for the nose rest of a conventional pair of eyeglasses to rest thereupon.
The bridge rest 20 is contoured with a generally hourglass-like shape such that the nose rest pads 25 of a conventional pair of eyeglasses 26, when placed within the eyeglass holder 10, is cradled in the bridge rest mid-section 27 of the bridge rest 20, preventing the eyeglasses from sliding in either a traversing or longitudinal direction. Placed in the eyeglass holder 10 with the nose rest pads 25 resting on the bridge rest 20, the eyeglass stems 28 extend back in a direction generally parallel to the stem supports 13 and intersecting the stem securing clasps 15.
The curved nature of the securing tabs 16 create a stem receiving cavity 17 into which the stem of a conventional pair of eyeglasses (not shown in FIGS. 1-3) can be inserted and secured. The securing tabs 16 are forced to distort by forcing the stem there between and the stem is allowed to enter the stem receiving cavity 17. The resilient nature of the securing tabs 16 forces them back together once the stem has entered the stem receiving cavity 17.
Optionally, a suction cup 30 allows for the eyeglass holder 10 to be secured to a smooth surface such as an automobile windshield, in a position of convenient access. The suction cup 30 is secured to the frame 11 by a mounting post 31 that is inserted into a suction cup securing aperture 32 molded in the design of the suction cup 30, although other securing means such as a hinge mechanism may be equally suitable.
2. Operation of the Preferred Embodiment
In accordance with the preferred embodiment of the present invention and as shown in FIGS. 4-5, the eyeglass holder 10 is used in the manner described herein below.
Depending upon the type of surface or structure that the eyeglass holder 10 is being used upon, the suction cup 30 may be attached to the frame 11 via the mounting post 31. The eyeglasses 26 are placed into the eyeglass holder 10 with the nose rest pads 25 supported by the bridge rest mid-section 27 of the bridge rest 20. The eyeglass stems 28 are inserted into the stem securing clasps 15 where they are retained by the securing tabs 16. Secured to the eyeglass holder 10 and positioned within the concave portion of the C-shaped frame 11, the eyeglasses 26 can be placed in a position of convenient location and retrieved both quickly and easily. The bridge support 12 and the stem supports 13 serve to protect the eyeglasses 26 from damage should they fall or otherwise become subject to a potentially damaging force. The bridge support 12 also serves to shield the eyeglass lenses 35 from scratches and abrasions.
While the preferred embodiments of the invention have been shown, illustrated, and described, it will be apparent to those skilled in this field that various modifications may be made in these embodiments without departing from the spirit of the present invention. It is for this reason that the scope of the invention is set forth in and is to be limited only by the following claims. | 4y
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RELATED APPLICATIONS
[0001] This application is a continuation of patent application Ser. No. 09/624,305, filed Jul. 24, 2000 which, in turn is a continuation of Provisional Patent Application No. 60\145,590, filed Jul. 26, 1999.
FIELD OF THE INVENTION
[0002] The present invention is directed to pharmaceutical compositions for transmucosal delivery of biologically active agents. More particularly, this invention relates to a novel method for controlling and promoting the rate and extent of transmucosal permeation and absorption of an anticonvulsive agent by coadministration of the medicament with a pharmaceutically acceptable co-solvent system comprising an aliphatic alcohol, a glycol, and water, and their combinations with a biological surfactant such as a bile salt or a lecithin. Even more particularly, this invention relates to the pharmaceutical compositions to provide a patient-acceptable transnasal anticonvulsive delivery system, which may be useful for the emergency management of status epilepticus and fever seizures in a prompt and convenient manner of administration.
BACKGROUND OF THE INVENTION
[0003] Status epilepticus is a neurological emergency in which mortality ranges from 3-35%. The major goal of treatment is rapid management of pathological seizure activity; the longer that the episode of status epilepticus is untreated, the more difficult it is to control and the greater the risk of permanent brain damage. Thus, critical to the management of the patient is a clear plan, involving prompt treatment with effective drugs in adequate doses having a proper pharmaceutical formulation as well as attention to hypoventilation and hypotension.
[0004] Currently several drug regimens have been proven to be applicable in treating status epilepticus. Diazepam and lorazepam are the most widely used benzodiazepines for this purpose. Intravenous administration of anticonvulsants is the most rapid way to suppress epileptic convulsions. However, other routes of administration may be highly desirable when intravenous administration is inconvenient and delaying, for instance, because of technical difficulties such as requirements for sterile equipment and skilled personnel, and because of the possible development of thrombophlebitis. In addition, intravenous medication is often associated with hypotension, cardiac dysrhythmia or central nervous system depression. In this regard Moolenaar [Moolenaar et al., Int. J. Pharm., 5: 127-137 (1986)] attempted to administer diazepam in humans via several other routes such as intramuscular injection, oral tablet and rectal solution. Only the rectal administration was found to provide a fairly rapid absorption and thus, it might be looked upon as an alternative route to IV injection. However, the rectal route is a very inconvenient way of drug administration particularly in emergency treatment. In U.S. Pat. No. 4,863,720 of Burghardt, a sublingual sprayable pharmaceutical preparation is disclosed, in which the active drug can be a benzodiazepine, optimally comprising polyethylene glycol (PEG) and requiring ethanol, di- and/or triglyceride of fatty acids and a pharmaceutically acceptable propellant gas.
[0005] More recently, it appears that the mucosal membrane of the nose offers a practical route of administration for therapeutic effect of many medicinal substances. Intranasal administration has the advantages that drugs may be administered readily and simply to achieve a systemic or localized effect, as required. However, the major problem associated with intranasal drug administration is the fact that most drug molecules diffuse poorly and slowly through the nasal mucosal membrane and thus the desired levels of the therapeutic agent cannot be achieved by means of simple transnasal administration. An additional constraint concerning nasal administration is that a small administration volume is needed; it is not generally possible to administer more than approximately 150 μl per nostril; above this, the formulation will be drained out into the pharynx and swallowed. Therefore, a great need exists for solvent vehicles, in which the solubility of the drug is high and which, on the other hand, are non-irritating to the nasal mucosa. The intranasal absorption of drugs can be increased by coadministering a chemical adjuvant or permeation enhancers. For example, Lau and Slattery [Lau et al., Int. J. Pharm., 54: 171-174 (1989)] attempted to administer a benzodiazepine such as diazepam and lorazepam by dissolving these medicaments in a variety of solvents; triacetin, dimethylsulfoxide, PEG 400, Cremophor EL, Lipal-9-LA, isopropyl adipate and Azone. While many of the solvents dissolved diazepam and lorazepam in the desired concentrations, they were too irritatable to be used, when administered to the nose. Cremophor EL was found to be the least irritating for nasal mucosal tissue, but the nasal absorption in the use of this vehicle in humans was rather slow (T max ≡1.4 hours) and the peak concentration was low relative to that observed after IV administration. In U.S. Pat. No. 4,950,664 of Rugby described the nasal administration of a benzodiazepine hypnotic in a pharmaceutically acceptable nasal carrier. The carrier may be an aqueous saline solution, an alcohol, a glycol, a glycol ether or mixtures thereof. The results of pharmacokinetic studies in dogs showed that the time to maximum plasma concentration for triazolam was achieved at 18 minutes after the nasal administration, while an effective treatment within 5 minutes is considered to be an attractive goal. Bechgaard and Hjortkjer [Bechgaard et al., J. Pharm. Pharmacol., 49: 747-750 (1997)] described the use of pure organic solvents such as glycofurol and tetraethyleneglycol, and their combinations as carriers for nasal delivery of diazepam. The absolute bioavailability, measured during the first 30 minutes, after the nasal administration, was 49-62% for the most promising carrier systems examined. In PCT WO 95/31217, Dumex described the use of a pharmaceutical emulsion preparation based on tocopherol and its derivatives for intranasal administration of biologically active compounds including benzodiazepines.
SUMMARY OF THE INVENTION
[0006] The present invention is a novel method of vehicle modulated administration of an anticonvulsive agent to the mucous membranes of humans and animals. The vehicle system is an aqueous pharmaceutical carrier comprising an aliphatic alcohol or a glycol and their combinations with a biological surfactant such as a bile salt or a lecithin.
[0007] An objective of the present invention is to provide a pharmaceutically acceptable carrier system which is capable of enhancing the transmucosal permeation and absorption of an anticonvulsive agent. The ingredients used in the pharmaceutical composition are preferably those of GRAS materials (generally recognized as safe), so there are no major toxicity issues of concern. Another objective of the present invention is to provide a method of controlling the transmucosal delivery of an anticonvulsant at an appropriately adjusted rate so as to achieve an optimum therapeutic effect, while avoiding or reducing adverse side effects. Such compositions are particularly suitable for intranasal administration of the medicaments in the acute treatment of status epilepticus and fever seizures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is a graph showing the effect of a vehicle on the in vitro transnasal permeation of diazepam preparations of the invention.
[0009] [0009]FIG. 2 is a graph showing the effect of drug concentration level on the in vitro transnasal permeation of diazepam from a vehicle of the invention.
[0010] [0010]FIG. 3 is a graph showing the influence of sodium glycocholate (SGC) on the in vitro transnasal permeation of diazepam from a vehicle of the invention.
[0011] [0011]FIG. 4 is a graph showing the mean plasma concentration-time profiles of diazepam after intravenous (IV) administration and intranasal administration of a preparation in accordance with the invention (a single dose application).
[0012] [0012]FIG. 5 is a graph showing the mean plasma concentration-time profiles of diazepam after intravenous and intranasal administration of a preparation in accordance with the invention (a multiple dose application).
[0013] [0013]FIG. 6 is graph showing the mean plasma concentration-time profiles of diazepam after intranasal administration of a preparation as a function of propylene glycol/ethanol volume ratio in the preparation according to the invention.
[0014] [0014]FIG. 7 is a graph showing the mean plasma concentration profiles of clonazepam after intravenous administration and intranasal administration of a preparation in accordance with the invention (a single and multiple dose application).
[0015] [0015]FIG. 8 is graph showing the mean plasma concentration-time profiles of (S)-2-carbamoyloxyl-1-o-chlorophenylethanol after intravenous administration and intranasal administration of a preparation according to the invention as a function of dose strength.
[0016] [0016]FIG. 9 is graph showing the mean plasma concentration-time profiles of (S)-2-carbamoyloxyl-1-o-chlorophenylethanol after intravenous administration and intranasal administration of a preparation according to the invention (a single and multiple dose application).
DETAILED DESCRIPTION OF THE INVENTION
[0017] In accordance with the present invention, a certain aqueous co-solvent system comprising one aliphatic alcohol, one glycol and a biological surfactant provides a rate-controlled and enhanced transnasal delivery of an anticonvulsive agent. The alcohol of the present invention is selected from C 1 to C 5 aliphatic alcohols; a glycol is selected from propylene glycol, polyethylene glycol (PEG) 200, PEG 300 and PEG 400, and PEG 600; and a biological surfactant is selected from bile salts such as sodium cholate, sodium deoxycholate, sodium taurocholate, sodium glycocholate, and sodium ursodeoxycholate or a lecithin such as lysophosphotidylcholine, dipalmitoylphosphotidylcholin, distearoylphosphotidylcholin, dipalmitoylphosphotidyl-ethanolamine, and dipalmitoylphosphotidylglycerol. The above-described compositions can be used for medicinal preparations comprising anticonvulsive agents applicable to the mucosal membranes of humans and animals. More specifically, these compositions are ones, which comprise a benzodiazepine such as diazepam, clonazepam, and lorazepam, and a mono-carbamate based new anticonvulsive compound, (S)-2-carbamoyloxyl-1-o-chlorophenylethanol represented by the following formula:
[0018] adapted for intranasal administration in a solution, suspension, gel or other useful nasal formulation. These nasal compositions may be employed for any of the known therapeutic purposes for which such anticonvulsants are known including phenytoins (phenytoin, mephenytoin and ethotoin), barbiturates (phenobarbital, mephobarbital, and primidone), iminostilbenes (carbamazepine), succinimides (ethosuximide), valproic acid, oxazolidinediones (trimethadione) and other antiseizure agents (gabapentin, lamotrigine, acetazolamide, felbamate, and γ-vinyl GABA). The utilization of an intranasal formulation of the anticonvulsant greatly facilitates administration. As compared with parenteral administration, for example, a simple sprayer, dropper or nebulizer will suffice for prompt and convenient delivery of the medicaments, in particular, for the emergency treatment of acute convulsive attack phenomena of epilepsy. From a clinical point of view, intranasal administration often provides an improved duration of anticonvulsive effect. By the present invention, the therapeutic effect, in terms of onset, intensity, and duration, can be more efficiently and accurately controlled by varying the proportion of aliphatic alcohol and glycol in the vehicle and by a single-dose and/or multiple-dose administration of the preparation of the invention. Although this invention has been described with respect to an anticonvulsant as a model compound, it is understood that this invention is also applicable to the other biologically active agents that are applicable to the mucosal membranes of humans and animals.
[0019] The invention is further illustrated by the following examples, which are illustrative of a specific mode of practicing the invention and is not intended as limiting the scope of the appended claims.
EXAMPLE 1
In Vitro Nasal Membrane Permeation Studies
[0020] The nasal mucous membrane used in these in vitro experiments was obtained from New Zealand White rabbits (2.5-3.0 kg). Rabbits were sacrificed by IV injection of phenobarbital. The nasal septum was carefully removed from a bone block using surgical scissors and a bone-cutting saw. Two pieces of nasal mucous membranes were then carefully stripped from the nasal septum without touching the center of the membrane surface and rinsed with normal saline solution. The mucosal membrane was mounted between two half-cells of a glass diffusion cell apparatus. The exposed area of the nasal membrane was approximately 0.64 cm 2 . A test solution or suspension (3.5 ml) was introduced into the mucosal side of the membrane in the donor compartment while 3.5 ml of 10% ethanol, 40% propylene glycol, and 50% pH 7.4 isotonic phosphate buffer solution was added to the receptor compartment. The entire diffusion system was maintained at 37° C. throughout the experiment. At predetermined time intervals, 100 μl of the receptor solution was withdrawn for the assay and refilled with the same volume of fresh receptor medium to keep the volume constant. The steady-state flux value was determined from the slope of the straight line attained from the plot of the cumulative amount of drug permeated as a function of time. Each experiment was carried out in at least duplicate. This method was used in Examples 2-6.
[0021] A high pressure liquid chromatographic system equipped with a multi-solvent delivery system (Model 600E, Waters Associates, Milford, Mass.), an auto-injector (Model 717 Plus, Waters Ass.), a photodiode array detector (Model 996, Waters Ass.), a reverse phase Symmetric C 18 column (150 mm×3.9 mm ID, 5 μm), and a Millenium 2010 software computer system were used in this study. The mobile phases and UV wavelengths utilized for the analysis of diazepam, clonazepam, and (S)-2-carbamoyloxyl-1-o-chlorophenylethanol were 70% methanol, 30% water at 254 nm; 60% methanol, 40% water at 252 nm; 25% acetonitrile, and 75% water at 262 nm, respectively.
EXAMPLE 2
[0022] This example shows the effect of a bile salt and a lecithin dissolved in an aqueous medium at a 1% w/v level on the in vitro permeation of a model drug diazepam through the freshly excised nasal membrane. In these studies, a series of bile salts such as sodium cholate, sodium deoxycholate, sodium taurocholate, and sodium glycocholate, and a lecithin such as lysophosphtidylcholine were examined. The permeation rates were measured using the method described under the in vitro membrane permeation test method. The average steady-state transnasal flux data obtained in this manner are presented in Table I.
TABLE I Effect of Bile Salts and Lecithin on the In Vitro Permeation of Diazepam across the Rabbit Nasal Mucosal Membrane at 37° C. Mean Transnasal Flux Vehicle (μg/cm 2 /hr) (n = 2) Water 79.5 1% Sodium Cholate/H 2 O 66.3 1% Sodium Deoxycholate/H 2 O 74.9 1% Sodium Taurocholate/H 2 O 87.0 1% Sodium Glycocholate/H 2 O 96.4 1% Lysophosphotidylcholine/H 2 O 125.5
[0023] As seen from Table I, a bile salt such as sodium glycocholate and a lecithin such as lysophosphotidylcholine produce a significant enhancing effect on the diazepam permeation through the nasal membrane.
EXAMPLE 3
[0024] This example exhibits the influence of a vehicle on the in vitro membrane permeation of diazepam across the rabbit nasal mucous membrane at 37° C. In this experiment, a 1% diazepam suspension and solution were prepared using water and a co-solvent vehicle consisting of 30% ethanol (ETOH), 60% propylene glycol (PG), and 10% water (WT), respectively. The permeation rates were determined utilizing the method described in Example 1. The transnasal permeation profiles of diazepam obtained in this manner are presented in FIG. 1.
[0025] As seen from FIG. 1, a co-solvent vehicle comprising ethanol, propylene glycol, and water provides an approximately 8 times increase in the transnasal permeation rate of diazepam when compared with that obtained with an aqueous suspension.
EXAMPLE 4
[0026] This example shows the influence of the drug concentration in the donor compartment on the permeation of diazepam through the nasal mucous membrane, in vitro. In this study, 0.5-2% diazepam formulations were prepared using a co-solvent mixture comprising 30% ethanol, 60% propylene glycol, and 10% water. The in vitro membrane permeation rates were measured using the test method described in Example 1. The in vitro transnasal flux data obtained with diazepam formulations over 0.5-2% level is shown in FIG. 2.
[0027] As seen from FIG. 2, the steady-state transnasal flux of diazepam increases linearly with increasing the drug concentration in the donor compartment over the 0.5-2.0% concentration level.
EXAMPLE 5
[0028] This example shows the effect of the incorporation of a bile salt into a nasal formulation according to the invention on the in vitro transnasal membrane permeation of diazepam. In this experiment, the inclusion of sodium glycocholate to a vehicle consisting of 30% ethanol, 60% propylene glycol, and 10% water at a 1% level was examined. Sample drug solutions (10 mg/ml) were prepared with the vehicle with and without the bile salt. The membrane permeation rates were measured in the use of the test method described in Example 1. The in vitro permeation profiles obtained in this manner are presented in FIG. 3.
[0029] As seen from FIG. 3, the inclusion of a 1% level of sodium glycocholate enhances the transnasal permeation rate of diazepam significantly. An approximately 50% increase in the steady-state flux is noticed when the bile salt is incorporated into the vehicle.
EXAMPLE 6
[0030] This example shows the comparative transnasal permeabilities of three model drugs such as diazepam, clonazepam, and (S)-2-carbamoyloxyl-1-o-chlorophenylethanol. In this experiment, a co-solvent vehicle consisting of 30% ethanol, 60% propylene glycol, and 10% water was used. The in vitro permeation experiments were performed using the test method described in Example 1. The comparative transnasal permeability coefficient and steady-state flux data obtained with the medicaments at an initial drug concentration of 5 mg/ml are presented in Table II.
TABLE II Comparative Transnasal Permeability of Model Drug Substances across the Rabbit Nasal Mucous Membrane In Vitro Permeability Transnasal Drug Compound Coefficient (cm/hr) Flux (μg/cm 2 /hr) Diazepam 4.92 × 10 −2 246.0 Clonazepam 6.95 × 10 −2 347.7 (S)-2-carbamoyloxyl-1-o- 9.77 × 10 −2 487.6 chlorophenylethanol
[0031] As seen from Table II, the monocarbamate based anticonvulsant, (S)-2-carbamoyloxyl-1-o-chlorophenylethanol appears to have approximately two times greater transnasal permeability as compared with that of diazepam.
EXAMPLE 7
Bioavailability and Pharmacokinetics of Diazepam Preparations
[0032] The bioavailability and pharmacokinetic characteristics of the preparations of the invention containing diazepam were tested after intranasal application to New Zealand White rabbits (n=3-4). For comparison, a diazepam injection (Formula 1 on Table III) was examined in vivo after intravenous administration of the same dose. IV Formula 1 (10 mg/2 ml) was obtained from Elkins-Sinn, Inc., which was prepared with propylene glycol (0.4 ml), alcohol (0.1 ml), benzyl alcohol (0.015 ml), sodium benzoate/benzoic acid (50 mg), and a sufficient quantity of water for injection to make 1 ml. For intranasal application, two formulations were prepared using a vehicle system of the invention consisting of 30% ethanol, 60% propylene glycol, and 10% water with (Formula 3 on Table III) and without (Formula 2 on Table II) 1% sodium glycocholate, respectively. Another nasal formulation (Formula 4 on Table III), prepared with a non-ionic surfactant vehicle of polyoxyethylated castor oil (Cremophor EL), was also tested after intranasal application for comparison since this formulation was tested in humans by Lau and Slattery (1989). All of the nasal formulations were prepared just prior to the experiments by dissolving 20-mg diazepam (Sigma Chemical) in 1 ml of the vehicles described above.
[0033] Just prior to the experiment, rabbits (n=3-4) were weighed and restrained in rabbit restrainers while they were facing up. Each rabbit received 100 μl of the Formula 2 or 3 into each nostril by means of a Pfeiffer spray device within 5 seconds. Rabbits (n=3) having IV administration received 1 mg/kg of Formula 1 as an ear-vein infusing during 20 seconds. For the repeated dosing studies, the same volume of Formula 3 (100%1) was sprayed into each nostril 5 minutes after the first dosing. Blood samples (1 ml) were collected at 0, 2, 5, 10, 20, 30, 45, 60, and 120 minutes after the IV and IN administration. From the blood samples, plasma was separated by centrifugation and stored at −20° C. until analysis. For analysis, plasma samples (0.5 ml) were accurately transferred into a 1.5 ml polypropylene centrifuge tube. To the plasma sample, 0.5 ml of 0.01% v/v perchloric acid in an acetonitrile containing internal standard (clonazepam 1 μg/ml) was added. The mixture was vortexed for 30 seconds and centrifuged at 4000 rpm for 10 minutes. The plasma concentration of diazepam was assayed by HPLC. The analysis was performed with the Waters HPLC as described in Example 1. The column used in this study was a 3.9 mm×150 mm×5 μm Symmetric C 18 column. The mobile phase was 50% methanol: 10% acetonitrile: 40% pH 3.5 phosphate buffer by volume. The flow rate of the mobile phase was 1 ml/min and the UV detection was made at 228.5 nm. The detection limit for diazepam was 70 nmol/l. The areas (AUC) under the drug plasma concentration-time curves, from 0 min to 120 minutes, were calculated by means of the trapezoidal rule. The bioavailability and pharmacokinetic data obtained in this manner are listed in Table III. The comparative pharmacokinetic profiles obtained after a single IV administration (Formula 1) and a single and double IN applications of the preparations of the invention (Formulas 3 and 4) are depicted in FIGS. 4 and 5, respectively.
TABLE III Bioavailability and Pharmacokinetic Parameter of Diazepam after IV and IN Administration of the Preparation of the Invention in Rabbits Route/ Dosing C max T max AUC (0-120 min) Formulation (mg/kg) (ng/ml) (min) (ng × min/ml) F (%) IV Single 398.8 2.0 17582 100.0 Formula 1 a (1 mg/kg × 1) (63.0) d (407) d (n = 3) IN Single 273.6 5.0 10383 59.1 Formula 2 b (1 mg/kg × 1) (62.2) d (692) d (n = 3) IN Single 273.7 2.0 13300 75.7 Formula 3 c (1 mg/kg × 1) (26.4) d (972) d (n = 4) IN Double f 327.1 2.0 26787 76.2 e Formula 3 c (1 mg/kg × 2) (29.7) d (4859) d (n = 3) 556.9 10.0 (130.5) d IN Single 73.3 30.0 7497 42.6 Formula 4 g (1 mg/kg × 1) (11.9) d (1445) d (n = 3)
[0034] As seen from FIG. 4 and Table III, IN Formula 3 prepared with 1% SGC, 30% ethanol, 60% PG, and 10% water increases the transnasal absorption markedly when compared with the Cremophor EL Formula 4. The C max and AUC 0-120 minutes for the IN Formula 3 are approximately 69% and 76% with reference to the IV administration, respectively. On the other hand, the C max and AUC 0-120 minutes for the Cremophor EL Formula 4 are about 19% and 42.6% of the IV injection. These comparative results appear to be conistent with the human pharmacokinetic data reported by Lau and Slattery (1989). According to the reported data, the Cremophor EL formulation yielded the T max of 1.4 hours after intranasal administration in humans and the C max was only about 27% relative to the IV injection. Surprisingly enough, as seen from FIG. 5 and Table III, a repeated intranasal application 5 minutes after the first dosing produces a marked increase in the transnasal absorption of diazepam. The C max and AUC values were exactly doubled after the second application relative to those obtained with the first administration. In addition, the plasma diazepam level attained after the second dosing exceeds that of the single IV administration within 7 minutes. These findings clearly demonstrate that a repeated dosing regimen (within a short period of time) can be effectively utilized for the acute management of epileptic seizures when a single intranasal dosing is incapable of producing the desired therapeutic effect.
EXAMPLE 8
Control of Peak Plasma Level Pharmacokinetics
[0035] Two mg of diazepam in a 100 μl vehicle was prepared and applied to rabbits (n=3) in a manner analogous to that described in Example 7. The following vehicles were tested: 60% ETOH, 30% PG, and 10% water (WT) with 1% SGC, 30% ETOH, 60% PG, and 10% water (WT) with 1% SGC, and 20% ETOH, 70% PG and 10% water (WT) with 1% SGC. Blood samples were collected from the ear vein at the following time intervals: 0, 2, 5, 10, 20, 30, 45, 60, and 120 minutes. The diazepam concentration in plasma was determined by HPLC. The pharmacokinetic profiles obtained after IV and IN administration of the preparations are presented in Table 1V and FIG. 6.
TABLE IV Effect of ETOH/PG Volume Ratio of the Vehicle on the Pharmacokinetic Parameter of Diazepam after IV and IN Administration of the Preparation of the Invention in Rabbits Route/ Dosing C max T max AUC (0-120 min) Formulation (mg/kg) (ng/ml) (min) (ng × min/ml) F (%) IV Single 398.8 2.0 17582 100.0 Formula 1 a (1 mg/kg × 1) (63.0) e (407) e (n = 3) IN Single 313.2 2.0 13592 77.3 Formula A b (1 mg/kg × 1) (17.3) e (692) e (n = 3) IN Single 273.7 2.0 13300 75.7 Formula B c (1 mg/kg × 1) (26.4) e (972) e (n = 4) IN Single 246.3 2.0 12860 73.1 Formula C d (1 mg/kg × 1) (32.2) e (827) e (n = 3)
[0036] As seen from Table IV and FIG. 6, the peak plasma concentration of the drug, observed within 2 minutes after the IN administration, can be controlled depending on the ETOH/PG volume ratio in the vehicles examined. The C max increases gradually with increasing the ETOH/PG volume ratio from 0.3 to 2. In addition, the peak plasma concentration for the IN vehicle consisting of 60% ETOH, 30% PG and 10% water (WT) with 1% SGC at 2 minutes is approximately 79% of an IV injection of the same dose.
[0037] In addition, modulating the ETOH/PG volume ratio in the vehicles can also control the plasma level-time profile in the elimination phase.
EXAMPLE 9
Pharmacological Response of Diazepam Preparations
[0038] The pharmacological response was examined in New Zealand White rabbits by evaluating muscle relaxation effect of diazepam after IV administration and IN administration of the preparations of the invention at a dosing level of 1 mg/kg. The vehicle of nasal formulation consisted of 30% ethanol, 60% propylene glycol, and 10% water containing 1% SGC. The sample formulation was prepared by dissolving 20 mg diazepam in 1 mL of the vehicle by ultrasonification. The IV formulation was the same as that used in Example 7. The pharmacological response was measured in rabbits after application of 100 μL of nasal formulation into each nostril while the rabbit was in a lying position after being firmly tipped with a finger on the hip. The mean response times that the rabbits remained in a lying position with its hind legs stretched to one side after IV and IN administration are listed in Table V.
TABLE V Mean Pharmacological Response Times after IV and IN Administration of Diazepam Preparations Route/Formulation Response Time (Min.) N IV Injection 1.1 ± 0.2 3 IN Formula 3 1.5 ± 0.5 3
[0039] As seen from Table V, the nasal formulation of the invention provides a very fast response. The time to pharmacological response was 1.5 minutes.
EXAMPLE 10
Bioavailability and Pharmacokinetics of Clonazepam Preparations
[0040] An intranasal formulation was prepared by dissolving 8.36 mg clonazepam in 2 ml of a vehicle of the invention consisting of 30% ETOH, 60% PG, and 10% water containing 1% SGC. A formulation for IV injection was prepared by dissolving 3-mg of clonazepam in 2 mL of a 40% PG, 30% ETOH, and 30% water solution and filtering the solution through a sterile filter under aseptic conditions. The formulations were administered to rabbits (n=3) at a dose of 0.2 mg/kg in a manner analogous to those described in Example 7. A repeated dosing regimen (double and triple application) at 5 minutes time intervals was also tested. Blood samples were obtained from the ear vein at the following time intervals: 0, 2, 5, 10, 20, 30, 45, 60, and 120 minutes. From the blood samples, plasma was separated by centrifugation and stored at −20° C. until analysis. For analysis, plasma samples (0.5 ml) were accurately transferred into a 15-ml test tube. To the plasma sample, 10 μl of an internal standard solution (diazepam—5 μg/ml) and 50 μl NaOH (0.5M) were added. To the above mixture, 5 ml of diethyl ether was added and this mixture was vortexed for 60 seconds and centrifuged at 4000 rpm for 10 minutes. The upper ethereal solution was transferred to a 5 ml test tube and evaporated in a vacuum evaporator at 40° C. for 30 minutes. The residue was reconstituted with 100 μl of the mobile phase for HPLC analysis consisting of 20% methanol, 30% acetonitrile, and a 50% pH 3.5 KH 2 PO 4 /H 3 PO 4 buffer solution. The clonazepam concentration in the plasma was determined by HPLC using a flow rate of 1 ml/minute and the UV detection at 254 nm. The detection limit for clonazepam was 16 nmol/l. The bioavailability and pharmacokinetic data obtained after IV and IN administration in a single and multiple dosing schedule are listed in Table VI and the mean plasma concentration-time profiles are shown in FIG. 7.
TABLE VI Bioavailability and Pharmacokinetic Parameters for Clonazepam after IV and IN Administration of the Preparations to Rabbits Route/ Formul- Dosing C max T max AUC (0 -120 min) ation (mg/kg) (ng/ml) (min) (ng × min/ml) F (%) IV Single 104.8 2.0 7437.7 100.0 Formula a (0.2 mg/kg × 1) (n = 2) IN Single 32.9 2.0 3356.4 45.1 Formula b (0.2 mg/kg × 1) (5.9) c (544.8) c (n = 3) IN Double f 49.5 10.0 4896.8 32.9 d Formula c (0.2 mg/kg × 2) (5.3) c (836.6) c (n = 3) IN Triple f 80.2 15.0 7766.1 34.8 e Formula d (0.2 mg/kg × 3) (21.3) c (2077.9) c (n = 3)
[0041] As seen from Table VI and FIG. 7, the initial peak plasma concentration is attained within 2 minutes after the first intranasal application of the preparation. The peak plasma level was about 32% of the IV injection. However, after the third application at 5 minutes intervals, the peak plasma concentration observed at 15 minutes was nearly identical to that of the single IV injection of clonazepam.
EXAMPLE 11
Pharmacological Response of Clonazepam Preparations
[0042] The pharmacological response of clonazepam preparations was examined in New Zealand White rabbits after application of 100 μL of the 4.18 mg clonazepam/mL vehicle into each nostril in a manner analogous to that described in Example 9. The vehicle consisted of 30% ETOH, 60% PG, and 10% water containing 1% SGC. Clonazepam was dissolved in the vehicle by ultrasonification. The IV formulation used in the study was the same as described in Example 10. The mean response times measured after the W and IN administration are presented in Table VII.
TABLE VII Mean Pharmacological Response Times after IV and IN Administration of Clonazepam Preparations Route/Formulation Response Time (Minutes) N IV Injection 1.7 ± 0.5 3 IN Formulation 1.4 ± 0.7 3
[0043] As shown in Table VII, the intranasal application of the clonazepam formulation of the invention provides a faster response time (1.4 minutes) when compared with that of IV injection (1.7 minutes).
EXAMPLE 12
[0044] Bioavailability and Pharmacokinetics of (S)-2-carbamoyloxyl-1-o-chlorophenylethanol Preparations
[0045] An intranasal formulation was prepared by dissolving 50 mg or 100 mg of a mono-carbamate based new anticonvulsive agent (S)-2-carbamoyloxyl-1-o-chlorophenylethanol in 1 mL of a vehicle of the invention consisting of 30% ETOH, 60% PG, and 10% water containing 1% SGC. A formulation for IV injection was prepared by dissolving 15 mg (S)-2-carbamoyloxyl-1-o-chlorophenylethanol in 1 mL of 40% PEG 400 and 60% water and filtering through a sterile membrane filter under aseptic conditions. The formulations were administered to rabbits (n=2-4) at the two dosing levels of 2.5 mg/kg and 5 mg/kg in a manner analogous to that described in Example 7. A repeated dosing regimen at 5 minute intervals was also studied in the nasal application of the preparation of the invention. Blood samples were obtained from the ear vein at the following time intervals: 0, 2, 5, 10, 20, 30, 45, 60, 120, 180 and 240 minutes. From the blood samples, plasma was separated by centrifugation and stored at −20° C. until analysis. For analysis, plasma samples (0.5 ml) were accurately transferred into a 15-ml test tube. To the plasma sample, 50 μl of an internal standard solution (2-(2,6-dichlorophenyl)-2-carbamoyloxyethyl)oxocarboxamide—10 μg/ml) and 5 ml of methylbutyl ether were added. The mixture was vortexed for 60 seconds and centrifuged at 3500 rpm for 10 minutes. The upper ethereal solution was transferred to a 5 ml test tube and evaporated in a vacuum evaporator at 40° C. for 30 minutes. The residue was reconstituted with 200 μl of deionized water. The (S)-2-carbamoyloxyl-1-o-chlorophenylethanol concentration in the plasma was determined by HPLC in the use of a mobile phase consisting of 20% acetonitrile and 80% water with a flow rate of 1 ml/minute and UV detection at 210 nm. The detection limit for (S)-2-carbamoyloxyl-1-o-chlorophenylethanol was 23 nmol/l. The pharmacokinetic parameters determined after IV and IN administration of (S)-2-carbamoyloxyl-1-o-chlorophenylethanol at two dose strengths are presented in Table VIII. The bioavailability and pharmacokinetic parameters obtained after IV administration and IN administration of the preparations of the invention in a single and double dosing regimen are listed in Table IX. The mean plasma concentration-time profiles obtained after IV and IN administration of (S)-2-carbamoyloxyl-1-o-chlorophenylethanol preparations in single and double dosing schedules are presented in FIGS. 8 and 9.
TABLE VIII Pharmacokinetic Parameters of (S)-2-carbamoyloxyl-1-o-chlorophenylethano after a Single IV and IN Administration at Two Dosing Strengths Route/ Dose Maximum T max AUC (0-240 min) Formulation (mg/kg) Conc.(ng/ml) (min) (ng × min/ml) F (%) IV Formula a 5.0 6267.7 2.0 473176 100.0 (408.0) d (56105) d (n = 4) IN Formula 1 b 5.0 2404.9. 30.0 373991 79.1 (130.0) d (5077) d (n = 3) IV Formula a 2.5 4179.9 2.0 221291 100.0 (n = 2) IN Formula 2 c 2.5 1407.2 5.0 160269 72.4 (n = 2)
[0046] [0046] TABLE IX Bioavailability and Pharmacokinetic Parameters of (S)-2-carbamoyloxyl-1-o- chlorophenylethano after IV and IN Administration of the Preparations in Single and Double Dosing Regimen Route/ Maximum Formul- Dose Conc. T max AUC (0-240 min) ation (mg/kg) (ng/ml) (min) (ng × min/ml) F (%) IV Single 6267.7 2.0 473176 100.0 Formula a (5 mg/kg × 1) (408.0) c (56105) c (n = 4) IN Single 2404.9. 30.0 373991 79.1 Formula b (5 mg/kg × 1) (130.0) c (5077) c (n = 3) IN Double e 4332.3 30.0 700475 74.0 d Formula b (5 mg/kg × 2) (979.3) (114195) c (n = 3)
[0047] As seen from Table IX, after the intranasal application the initial peak concentrations observed within 5-30 minutes increased proportionally with increasing the dose strength. The bioavailability of the nasal preparations is found to be 73-79% of the IV injection. The pharmacokinetic results presented in Table IX and FIG. 9 clearly demonstrate that the second application of the intranasal formulation 5 minutes after the first dosing produces a nearly identical bioavailability to that obtained after the first dosing. The C max and AUC 0-240 minutes are doubled after the second intranasal application. In addition, the plasma concentration of (S)-2-carbamoyloxyl-1-o-chlorophenylethanol achieved after the second dosing exceeded the plasma level obtained with a single IV injection at 30 minutes.
EXAMPLE 13
Stability Studies
[0048] In an effort to optimize the stability of the medicaments in the pharmaceutical compositions according to the present invention, an accelerated stability study was performed at a storage temperature of 37° C. over a 10-14 weeks time period. Sample drug solutions (0.1 mg/ml) were prepared using a vehicle of the invention consisting of 30% ETOH, 60% PG, and 10% water. The drug solutions were stored in an oven set at 37° C. At appropriate time intervals, a 100 μl sample was withdrawn and analyzed by means of HPLC. The chemical stability data determined in terms of the percent drug recovery are presented in Table X.
TABLE X Chemical Stability of the Preparations of the Invention at 37° C. Drug Formulation Storage Time (Weeks) % Recovery Diazepam Formulation 0 100.0 4 100.3 10 102.4 14 102.6 Clonazepam Formulation 0 100.0 4 101.7 11 100.9 (S)-2-carbamoyloxyl-1- o-chlorophenylethanol Formulation 0 100.0 3 100.2 4 98.2 9 98.0 12 97.6 | 4y
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PRIOR APPLICATION
This application is a continuation-in-part of Provisional Application of U.S. No. 60/092,746 filed on Jul. 14, 1998 and which is fully incorporated herein by reference thereto.
FIELD OF THE INVENTION
The present invention relates to lockable enclosures, and, in particular, to lockable enclosures which have electronically operated locks. Specifically, the present invention relates to latch assemblies capable of preventing the electronically operated locks of lockable enclosures from an accidental release.
BACKGROUND OF THE INVENTION
It is difficult to imagine a modern life without lockable enclosures and, particularly, portable lockable enclosures. Such lockable enclosures including, for example, a briefcase, a suitcase, a portable safe and the like are typically used for storing and safe transportation of documents, jewelry, personal belongings and the like. Practically, all of these enclosures have latch assemblies of different types, some of which employ electronically operated locks that serve to prevent unauthorized access to an enclosure's interior. A reliable latch assembly for a lockable enclosure becomes even more important when the latter stores a firearm.
The art does supply a number of small portable safes, which may be easily carried by owners while they are travelling.
U.S. Pat. No. 5,416,826 to Butler discloses an electronically operated gun safe which has a drawer removably positioned with a housing to move to an open position to allow access to the contents of the drawer. This patent further describes an electronic code entry means and a processor means positioned in an interior and responsive the electronic code means for releasing a locking means to provide access to the drawer.
U.S. Pat. No. 4,800,822 to Adkins discloses a spring loaded ejectable drawer containing a firearm and slidably mounted within a housing. The drawer bears against a closed door of the housing, so that, upon opening of the door, the ejectable drawer is forced outwardly to present the firearm for grasping.
U.S. Pat. No. 5,901,589 to Cordero discloses a storage body for receiving a firearm and formed with a door, a plurality of grooves inside the storage body surrounding the door to permit it to move inwardly to an opening position. This patent further describes a spring biasing means for holding the door tightly against the storage body that is releasable by a hidden latch mechanism accessible from outside the body and opening the door.
It has been noticed that some of the locking mechanisms tend to voluntary release its latches when the portable safes are accidentally dropped or even deliberately positioned on its rear portions.
SUMMARY OF THE INVENTION
With a safe including a lockable enclosure that has an interior sized to receive valuables such as guns and the like and that is provided with an inventive latch assembly, some of the drawbacks of the prior art may be overcome. The latch assembly has a means for preventing accidental release of the latch assembly when the lockable enclosure is positioned on its rear portion.
According to another aspect of the invention, the lockable enclosure is provided with a cam mechanism positioned in an interior of the lockable enclosure and operated to controllably release the latch assembly.
In accordance with another feature of the invention, the lockable enclosure has an electronic key assembly for permitting entry of a key code to enable the cam mechanism.
It is therefore an object of this invention to provide an improved lockable enclosure overcoming some of the disadvantages of the known prior art.
Still another object of the invention is to provide a lockable enclosure with a latch assembly that is secured against accidental release when the lockable enclosure is positioned on its rear portion.
Yet another object of the invention is to provide a lockable enclosure with a cam mechanism releasing the latch mechanism in response to a predetermined signal.
Still another object of the invention is to provide a lockable enclosure with an electronic key assembly enabling the cam mechanism.
The above and other objects, features and advantages will become more readily apparent from the following detailed description of the invention and accompanying drawings, which set forth an illustrative embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 isometric view of a lockable enclosure positioned on its bottom.
FIG. 2 is an exploded view of the lockable enclosure of FIG. 1 .
FlG. 3 is a top view of the safe shown in FIG. 1 with a portion cut away for clarity.
FIG. 3A is a perspective view of a latch assembly.
FIG. 4 is a cross sectional view of the latch assembly shown in its engaging position corresponding to a locked state of the lockable enclosure.
FIG. 5 is a cross sectional view of the latch assembly similar to the one shown in FIG. 4 and illustrating the latch assembly in its release position.
FIG. 6 is a cross sectional view of the latch assembly provided with a stop that prevents accidental release of the lath assembly when the lockable enclosure is positioned on its rear portion.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1-3, a lockable enclosure 10 is a self-contained, electronically controlled containment system, such as, for example, a safe for storing a variety of valuables including guns and the like. The safe 10 can be positioned on any generally flat surface juxtaposed with either the safe's bottom 16 or its rear side 18 .
FIG. 1 illustrates the safe 10 shown in its locked state and having a solid cast enclosure 12 . A lid 14 , sometimes referred to as a door, is mounted to the enclosure 12 to move to an open position as shown in FIG. 2 . The safe further has a protrusion 20 formed with a recess 21 that receives a keypad system 22 including a plurality of keys or buttons 24 used to customize a user's personal access code. As better seen in FIG. 3, the buttons are provided with standard numeric digits. By dialing the personal access, a user may access an interior of the enclosure 12 , as will be explained hereinbelow.
As shown in FIG. 2, the safe 10 has a top wall 26 and a receptacle part 28 , which parts when assembled form an interior of the safe sized to receive the valuables. Any suitable fasteners may do assembly of the top wall and receptacle part 28 , for example, screws 30 traversing aligned holes 32 that are formed on the top wall and the receptacle part. The safe 10 further has a mounting bracket 34 for mounting the safe 10 to a surface if the safe 10 is intended to be secured in a predetermined location. The mounting bracket is detachably secured to the bottom 16 of the safe 10 and is described in detail in a coopending application Ser. No. 09/352,220 filed concurrently with the present application. The enclosure further has a cushioned receptacle 36 secured to the receptacle part 28 and made of light durable material, for example, plastic.
Turning to FIG. 2, the safe 10 in accordance with one aspect of the invention, has an electronic key assembly including the keypad 22 and a processor 38 , which is only shown diagrammatically and known in the art. Typically, the processor 38 stores key code data and has an operating program located in a digital memory that is located within the processor. When a key code has been entered, it is transferred to the processor 38 via a ribbon cable 40 . If the key code matches the key code data that has been stored in the digital memory, the electronic key assembly actuates a cam mechanism as will be explained hereinbelow. The electronic key assembly also includes an alarm circuitry turning on a sound system (not shown here) indicating that an unauthorized code has been entered. This sound system is also set off when either of main 42 and spare 44 batteries is low. The main battery 42 is placed in a recessed seat 46 formed in a front portion 48 of the top wall 26 . The keypad 22 is provided with a keypad back light that is activated by pressing any of the keys 24 before the personal code is entered.
Although the keypad 22 and the main battery 42 are shown to be formed in respective indented regions of the top wall 14 , they may alternatively be mounted in one or more of the other outer enclosure walls provided it is exposed to the exterior of the enclosure 12 and is easily accessible by a user.
As mentioned above, according to another feature of the invention, the electronic key assembly actuates the cam mechanism generally indicated as 50 as seen in FIG. 2 . The key assembly includes a low rpm motor 52 actuated by the processor 38 in response to the correct key code and a reduction gear train 54 translating rotational motion of the motor's shaft to an output shaft 56 . The output shaft 56 has two cams 58 , 60 mounted rotatably on this shaft so that the cam 60 juxtaposed with a release lever 62 may actuate it.
The release lever 62 is mounted on an L-shaped support 64 extending between opposite sides of the receptacle part 28 and extending from this part to provide a mounting surface for the spare battery 44 and the release lever 62 . The support 64 also serves as a reinforcing surface for the cushioned receptacle 36 .
As shown in FIG. 2, the enclosure is provided with a pair of pins, each mounted on a side wall and extending toward the opposite wall. Each of the pins has a torsion spring 68 , one end of which is braced against the pin.
Referring to FIGS. 4-6, the release lever 62 is preferably made of resilient material, for example, plastic and is mounted pivotally on the support 64 to swing about a fulcrum 66 formed on a lower end of the release lever. To provide a continuous contact between the cam 60 and the release lever 62 a spring element 68 is braced against the L-shaped support 64 and extends toward the release lever 62 to bias it against the cam 60 . Thus, a cam follower 70 of the release lever follows displacement of the cam 60 bringing an outer T-shaped end 72 (FIG. 3) of the release lever into engagement with a latch assembly 74 , as will be explained hereinbelow.
According to another aspect of the invention, the latch assembly generally denoted as 74 , is mounted to an underside of the door 14 and extends under a flange 27 of the top wall 26 in a closed position of the door 14 , as shown in FIG. 4 .
Particularly, the latch assembly 74 is comprised of a bracket 76 having generally a U shape. A plate 78 , better seen in FIG. 5, covers the bracket 76 to form a compartment 77 , which is defined between a bottom 80 of the bracket and the plate 78 . The bracket and the plate 78 are formed with aligned holes receiving fasteners (not shown) for attaching the latch assembly 74 to the underside of the door 14 . The compartment 77 receives a latch 82 and a spring element 83 that biases the latch 82 outwardly from the bracket. In order to arrest displacement of the latch from the compartment 77 , FIGS. 3 and 3A illustrate the bottom 80 of the bracket 76 having end portions 84 extending toward the plate 78 . These portions 84 form stops, which cooperate with recessed portions 88 of the latch 82 in the closed position of the door 14 , and allow only a beveled edge 81 (FIG. 5) of the latch 82 to extend over the bracket toward the flange 27 of the enclosure. A rear portion of the latch 82 is formed with a pair of spaced grooves 90 (only one is shown) which receive ends of the spring elements 83 respectively. Opposite ends of the spring elements urge against a rear wall of the bracket.
The bottom 80 of the latch assembly 74 has a cavity 85 which is formed substantially midway between the recessed portions 88 of the latch 82 and extends downwardly therefrom and between a front edge 92 of and a rear wall 94 of the bracket 76 . As a result, space formed between the latch 82 and the cavity 85 receives a ball bearing 96 that is freely displaceable in the cavity under the latch 82 in a substantially horizontal position of the safe 10 shown in FIGS. 4 and 5.
Since the safe 10 is portable and can be used for travel or relocation, the user may either accidentally drop the safe on its rear side 18 (FIG. 6) or intentionally position the safe on this rear side. In this position of the safe, the ball bearing 96 freely rolls to occupy space between the rear wall 94 of the bracket 76 and a rear side of the latch 82 , as shown in FIG. 6 to prevent rearward displacement of the latch 82 .
Although the cam mechanism 50 and the latch assembly 74 have been described to be mounted to the enclosure 12 and to the door 14 respectively, it is clear that their respective positions can be easily reversed.
The safe operates in the following manner. Upon placing valuables in the cushioned receptacle 36 , the user simply pushes the door 14 downwardly to its closed position. During angular displacement of the door 14 , the flange 27 of the enclosure's top wall 26 comes in contact with the beveled edge 81 of the latch 82 that retracts into the compartment 77 of the bracket 76 . Having reached a closed position, the latch, under the action of the spring force of spring elements 83 , advances away from the rear wall 94 of the bracket to abut an underside of the flange 27 , thus engaging the latch with the enclosure.
To open the safe, the user dials the access code activating the processor 38 which, in turn, actuates the cam 60 to rotate at a 180° angle from a position shown in FIG. 4 to a position shown in FIG. 5 . In this latter position the release lever 62 overcomes a force exerted by the leaf spring 68 to displace the latch rearwardly toward the back wall 94 of the bracket 76 , thus releasing the latch assembly 74 from the enclosure. As a result, the door 14 swings up to its open position.
Although the latch assembly is described to operate the safe 10 , it is easy to see that such latch assembly can reliably lock a variety of suitcases, briefcases, bags and the like. It is also possible to utilize the disclosed latch assembly with any lockable item that can be placed in a position in which voluntary release of a latch is possible.
It is intended that the flowing claims defined the scope of the invention and the structures within the scope of these claims and their equivalents be covered thereby. | 4y
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BACKGROUND OF THE INVENTION
[0001] The present invention relates to the demounting of a cable tensioned between two anchorage points on a structure.
[0002] Such demounting is often considered as problematic, in particular when no specific device has been provided during the initial design of the structure with which the cable participates.
[0003] First of all, the fact that the cable is tensioned between anchorage points prevents it from being freed simply from the structure.
[0004] Then, even once the cable has been freed from the structure, it is still likely to damage the latter. If the structure is in service, as in the case of a bridge of which the deck is subject to motor vehicle traffic for example, demounting the cable may also bring about a relatively long interruption of service.
[0005] An object of the present invention is to make it possible to demount the cable more easily.
SUMMARY OF THE INVENTION
[0006] The invention therefore provides a method for demounting a cable tensioned between a first and a second anchorage point on a structure comprising the following steps:
freeing a running part of the cable from said first and second anchorage points; supporting said running part of the cable; and removing said running part of the cable away from at least one of said first and second anchorage points.
[0010] According to this method, supporting and removing said running part of the cable are performed with the aid of a plurality of supports distributed along said running part of the cable and forming cradles for said running part of the cable, each held by at least one other cable situated higher than said cable, the cradles being connected to each other and being mounted so that they can move along said other cable.
[0011] Advantageously, freeing the running part of the cable from said first and second anchorage points comprises slackening the cable so that the running part of the cable is freed from one of said first and second anchorage points and freeing the running part of the cable from the other of said first and second anchorage points
[0012] Such preliminary slackening of the cable ensures to free a significant part thereof, with no danger for the close surroundings of the cable, and the support of the running part of the cable also allows to avoid damaging the structure with which the cable participates.
[0013] The invention also provides a device for supporting a cable tensioned between a first and second anchorage point on a structure, the support device comprising:
a plurality of cradles capable of being distributed along a running part of the cable to constitute supports for said running part of the cable; means so that each cradle of the plurality rests on at least one other cable situated higher than said cable and can move along said other cable; and means connecting the cradles to each other.
[0017] The invention also provides a system for demounting a cable tensioned between a first and second anchorage point on a structure, the system including a support device comprising:
a plurality of cradles capable of being distributed along a running part of the cable to constitute supports for said running part of the cable; means so that each cradle of the plurality rests on at least one other cable situated higher than said cable and can move along said other cable; and means connecting the cradles to each other,
and a bridging device for slackening the tensioned cable, comprising:
two collars capable of being positioned around the cable so as to ensure substantially non-sliding contact along the cable; traction bars connecting said collars; means for adjusting the tensile force passing in the traction bars; and means for monitoring the tensile force passing in the traction bars.
[0025] Other features and advantages of the present invention will become apparent from the following description of examples of non-limiting embodiments, with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a diagram representing an example of a tensioned cable to be demounted;
[0027] FIG. 2 is a diagram illustrating bridging devices used to slacken the cable of FIG. 1 ;
[0028] FIGS. 3 to 5 are diagrams showing successive steps for slackening a cable according to an advantageous embodiment of the invention;
[0029] FIG. 6 is a diagram showing a procedure for supporting the cable of FIG. 1 once slackened;
[0030] FIG. 7 is a diagram showing another procedure for supporting the cable of FIG. 1 once slackened;
[0031] FIG. 8 is a transverse view of part of the support device used according to the support procedure of FIG. 7 ;
[0032] FIG. 9 is a diagram showing an intermediate step for removing the cable of FIG. 1 according to an advantageous embodiment of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0033] The invention is described hereinafter in the non-limiting example of a stay cable. It applies however to any other type of cable tensioned between two anchorage points on a structure (carrying cable of a suspension bridge, prestressing cable, etc).
[0034] FIG. 1 shows a stay cable 1 tensioned between two anchorage points on a cable-stayed bridge 2 . The first anchorage point 5 is situated on a pylon 3 of the bridge 2 , while the second anchorage point 6 is situated on the deck 4 of the bridge 2 .
[0035] Although not shown in FIG. 1 , other cables substantially parallel to cable 1 can be tensioned between the corresponding anchorage points on the bridge 2 .
[0036] The present invention aims to demount the cable 1 without damaging the bridge 2 or any other cables anchored to the bridge 2 .
[0037] To this end, the cable 1 may be slackened so that a running part of this cable is freed from the anchor 5 and/or the anchor 6 which connect it to the structure 2 .
[0038] It will be recalled that freeing a linear structural element composed of one or more metal strands highly tensioned between two points considered to be relatively fixed, as is the case of cable 1 of FIG. 1 , is often problematic, in particular when no specific device has been provided during the initial design.
[0039] In particular, a reduction in the resisting section of such a cable by cutting it, without taking special precautions, would cause the stresses in the remaining section to increase until the breaking stress of the material is reached. Breakage resulting from this would be sudden and would produce harmful dynamic effects, since the sudden freeing of energy stored in the cable could bring about large rapid uncontrolled deformations (“whip effect”) that would be extremely dangerous for the immediate environment of the cable, that is to say for the structure with which the cable participates, but also for the personnel responsible for cutting the cable.
[0040] Slackening the cable 1 advantageously makes it possible to limit these disadvantages. It could for example be achieved by placing, close to the top anchorage point 5 and/or the bottom anchorage point 6 of the cable 1 , a bridging device 7 capable of taking up the tensile force of the cable on a portion thereof (see FIG. 2 ).
[0041] As is apparent in FIGS. 3 to 5 , this bridging device 7 may comprise two clamping collars 12 positioned around the cable 1 to provide a structural connection therewith. Each of these collars 12 preferably has the ability to withstand the tensile force F of the cable 1 substantially without sliding along this. In particular, if the cable 1 is provided with a sheath surrounding the metal strands of which it consists, this sheath is advantageously withdrawn at right angles to the collars 12 .
[0042] In addition, in the example illustrated in FIGS. 3 to 5 , the traction bars 13 connect the collars 12 so as to form the actual bridging. The traction bars are advantageously at least two in number and are preferably positioned so that their centre of gravity is situated substantially at the same place as that of the cable 1 to be slackened. They are chosen so as to be capable of withstanding the tensile force F to which the cable 1 is initially subjected.
[0043] In the example illustrated in FIGS. 3 to 5 , the means 14 for adjusting the tensile force passing through the traction bars 13 have been shown. The means for adjustment 14 may for example comprise jacks.
[0044] In addition, the means 15 for monitoring the tensile force passing in the traction bars may also be used. In the figures, the means 14 for adjusting, and the means 15 for monitoring the tensile force have been shown close to the opposite ends of the traction bars 13 . It will however be understood that such means can be positioned differently, for example on the same side of the traction bars.
[0045] In the step illustrated in FIG. 3 , the cable 1 is subjected to the tensile force F which corresponds to the initial tension of the cable over all its length comprised between the anchorages 5 and 6 . At this stage, the tensile force in the bridging device is nil or virtually nil.
[0046] Subsequently, the traction bars 13 of the bridging device 7 are tensioned (which is symbolised in FIG. 4 by the tension f) until the sum of their tensions reaches a value greater than or equal to an assumed value for the tensile force F of the cable 1 . Of course, if the value of the tensile force F is known, it will be possible to tension the traction bars 13 in order to reach this value precisely.
[0047] Following this operation, the force F has been totally transferred to the portion under consideration 11 of the cable 1 to the corresponding bridging device 7 . The portion 11 of the cable is then subjected to a force that is virtually nil.
[0048] On account of this, said portion 11 of the cable placed between the clamping collars 12 may then be divided into sections without danger, as illustrated in FIG. 5 . Division of the portion 11 of the cable into two sub-portions 11 a and 11 b may be achieved in different ways, for example by successively cutting each strand of the cable 1 or by localised intensive heating of this portion of the cable until it breaks.
[0049] During the step of dividing the cable into sections, it may be advantageously verified, with the aid of the monitoring means 15 , that the tensile force in the bridging device varies relatively little. This guarantees in point of fact that the bridging device has indeed locally taken up all the tensile force F to which the cable 1 was initially subjected.
[0050] Once the cable 1 has been divided into sections, the tensile force in the bridging device can be progressively released until annulled with the aid of the means for adjustment 14 . The consequence of this is to slacken the cable 1 in its entirety. The means 15 for monitoring the tensile force can advantageously be used to check this operation.
[0051] It will thus be understood that the cable 1 has been slackened without any sudden variation in force having been encountered, since division of the cable into sections took place in a portion where its stressed state was virtually nil.
[0052] Following the advantageous operations described above, the running part of the cable 1 is freed from the top anchor 5 and/or the bottom anchor 6 . When slackening has been achieved close to only one of these anchorage points, for example the bottom anchorage point 6 which is the more accessible, the running part of the cable is then freed from the other anchorage point, for example the anchorage point 5 . This second freeing may be achieved for example by simply dividing said portion of the cable close to the other anchorage point. No bridging device is necessary for this cutting which does not present any danger, the cable having already been slackened. As a variant, freeing of the running part of the cable from the other anchorage point could result from withdrawal of said cable from said other anchor. The running part of the cable is then totally freed from the top 5 and bottom 6 anchors (as symbolised by the crosses close to these anchors in FIGS. 6 and 7 ).
[0053] The running part of the cable 1 is then supported so as not to sag under the effect of its own weight, which would risk damaging the deck 4 of the bridge 2 and the other cables which may be situated under the cable 1 .
[0054] In an example illustrated in FIG. 6 , the running part of the cable 1 , once slackened, is supported with the aid of the support 10 on which it partly rests, this support 10 being itself held by an auxiliary structure 15 of the crane or scaffolding tower type for example. Thus, the running part of the cable is lifted locally in the region of the support 10 , which ensures that it is held while waiting to be removed.
[0055] FIG. 7 illustrates another example in which a plurality of supports 18 support the running part of the cable 1 while waiting for it to be removed. These supports 18 are advantageously distributed, possibly in a uniform manner, over all the length of the running part of the cable 1 .
[0056] The supports 18 advantageously form cradles receiving the running part of the cable 1 as illustrated in FIG. 8 . They are held by one or more cables 20 situated higher than the cable 1 , to which they are connected via the hangers 17 for example. In the example illustrated in FIG. 8 , the cradles 18 are thus suspended so as to rest on two cables 20 situated either side of the cable 1 .
[0057] The cradles 18 are advantageously connected together and mounted so as to be able to move along the cables 20 . In the example illustrated, this movement is ensured by the rollers 16 to which the hangers 17 are connected and which are capable of rolling on the cables 20 .
[0058] The cables 20 which ensure that the cradles 18 are held in place may be cables of which the structure 2 consists, for example stay cables permanently tensioned between the pylon 3 and the deck 4 of the bridge 2 , in the manner of the cable 1 .
[0059] As a variant, these cables 20 can be provisionally mounted on the structure 2 so as to support the cable 1 to be demounted. In this case, it will be possible for the cables 20 to be anchored in anchorage blocks provisionally connected to the pylon 3 and the deck 4 , rather than directly in the pylon 3 and the deck 4 . These anchorage blocks are then placed close to the anchorage points 5 and 6 of the cable 1 . In this way, the provisional cables 20 can be withdrawn from the structure 2 , once the cable 1 has been demounted.
[0060] When the support device described with reference to FIGS. 7 and 8 is used, the sequence for demounting the slackened cable 1 can then proceed in the following manner.
[0061] The assembly composed of the running part of the cable 1 and the cradles 18 on which this part of the cable 1 rests is allowed to descend progressively. Progressive descent is advantageously achieved using the means 19 capable of holding the running part of the cable 1 , as illustrated in FIG. 9 . A controlled delivery cable connected to the cable 1 can for example consist of such holding means 19 . As a variant or a complement, the holding means can be positioned so as to control the descent of the cradles 18 .
[0062] During the descent, the rollers 16 roll over the cables 20 , which causes the cradles 18 and the running part of the cable 1 which they support to be entrained towards the deck 4 of the bridge 2 . In this way removal of the running part of the cable 1 is ensured away from the top anchor 5 by which the cable 1 was initially fixed to the pylon 3 of the bridge 2 .
[0063] It will moreover be noted that parts of the cable 1 remaining fixed to the top 5 and bottom 6 anchors, after freeing the running part of the cable 1 , will be advantageously withdrawn from their respective anchors in order to be removed.
[0064] Advantageously, the running part of the cable 1 can be divided into sections during its removal. This can be achieved by cutting the cable 1 into elements with a reduced length, preferably lengths that can be easily transported by road, as the cable descends towards the deck 4 of the bridge 2 .
[0065] FIG. 9 illustrates an intermediate step in the demounting of the cable 1 , in which a new element 21 has been obtained by cutting the portion of the cable 1 which has just arrived close to the deck 4 . As regards the elements 22 , these represent elements of the previously cut cable 1 that are collected together substantially in the same place with a view to their possible final removal away from the bridge 2 .
[0066] The demounting process is then continued in the same way until the running part of the cable 1 has fully descended to the deck 4 of the bridge 2 and possibly been cut into elements of reduced length 22 . The elements 22 obtained may then be removed away from the bridge 2 .
[0067] At the conclusion of these operations, all the supports 18 , hangers 17 and rollers 16 are collected together close to the deck 4 of the bridge 2 . They can then be recovered so as to serve in demounting another cable. When the cables 20 are provisional, they can in their turn be withdrawn from their anchors.
[0068] Easy demounting of the cable 1 can be obtained in this way, without this cable damaging the structure 2 , or any other stays of the bundle to which the cable 1 belongs. Moreover, disruption to the traffic on the bridge 2 is minimized as the cable 1 is demounted. In addition, demounting can be carried out without any means having been provided for this purpose when the structure 2 was designed.
[0069] It will be noted in particular that the support device described with reference to FIGS. 7 to 9 is particularly advantageous since it comprises light means capable of contributing to the support and also removal of a large part of the cable, in spite of the large weight of the cable and of the great height of the top anchor 5 to which the cable 1 was initially fixed. | 4y
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This is about a process of conversion of gas molecules through thermal plasma technology, an industrial process capable of changing the chemical composition of greenhouse gases emitted as exhaust from internal combustion engines, factory chimneys, etc. This process of conversion degrades or decomposes the gas molecules and forms new substances, e.g. carbon dioxide (CO 2 ), which is one of the main components of greenhouse gases, and whose conversion products, by this process are solid carbon and gaseous oxygen (O 2 ). Molecular conversion unity with a solid particle trap consists of plasma combustion chamber and an electrostatic filter for the collection of solid particles. The plasma combustion chamber has a plasma torch that produces a plasma jet or ionized gas formed by discharge between a cathode and an anode.
THE TECHNICAL STATE
One of the most serious problems faced by man today is the environmental pollution, which result mainly from human and industrial activities. Fossil fuel burning (such as petrol, coal, and natural gas) is one of the main reasons for the increase of carbon dioxide (CO 2 ) in the atmosphere of the planet. About 24,000 million tons of CO 2 have been released annually, the equivalent of 6,500 million tons of carbon per year. The concentration of carbon dioxide in the atmosphere, measured by Mauha Loa Observatory, Hawaii, in January of 2007, was 0.0383% in volume (383 ppm/v): 105 ppm/v of 38% over the average of the observed values up to 1950. The average temperature of Earth's atmosphere is kept constant due to the physical and chemical properties of certain gaseous molecules called greenhouse gases, such as CO 2 . If the concentration of such gases changes there will also be changes in the planet's temperature. The main greenhouse gases causing global warming are: water vapor, which causes about 36 to 70%; carbon dioxide (CO 2 ), which causes about 9 to 26%; methane (CH 4 ), which causes about 4 to 9%; and finally the ozone (O 3 ), which causes about 3 to 7%.
Nitrous Oxide (N 2 O) and CFC's like chlorofluorocarbons (CF x Cl x ) are other greenhouse gases of less concentration in the atmosphere. In the face of such a critical situation, researchers all over the world seek technologies to control and retain greenhouse gas emissions. The patent documents PI8100960-7, PI9500855-1, PI0205677-1, PI0301592-0, PI0305789-5, PI0317946-0, JP2003326155 and PI0604646-0 describe equipment and processes of carbon dioxide gas absorption in the atmosphere. The dominant technology today searches for a solution by improving the chemical reaction processes. But it should be noted that there exist no industrial installation using thermal plasma technology aimed at conversion of greenhouse gas molecules and production of new substances. Information concerning this invention may be accessed at http.//www.cmdl.noaa.gov/ccgg/trends/, (Jan. 18, 2007), and in “Shukman, David (14 Mar. 2006). Sharp rise in CO 2 , levels Recorded. BBC News”.
In relation to thermal plasma technology, it is necessary to consider different ways of producing plasma, and any such choice depends on the aim of the application. The most used methods are inductive coupling plasma (ICP) and DC arc plasma (direct current). Radio frequency produces ICP, which is used mainly for analytical purposes. It is formed by a gas flow, normally argon gas, which crosses an area with an induction coil fed by a radio-frequency generator system. The induction coil comprises 2 or 4 inner water-cooled turns. This kind of plasma is also used for liquid chemical waste treatment. The waste is injected into the center of the torch where the temperatures are higher, and this contributes to its total destruction.
DC Arc Plasma: When the gas flows between two electrodes under a potential difference and high current in the presence of some negative or positive charge carriers, an arc is established between the electrodes forming direct current (DC) plasma or alternating current (AC) plasma. The electric arc may be free (arc welding or arc furnace) or confined (in a plasma torch). The process of heat exchange between the arc and the environmental gas occurs by natural convection in the free arc. In the confined arc, the exchange takes place by forced convection, which is much more efficient than the natural one. Due to that efficiency, the temperature in the confined arc (20,000K) is much higher than the temperature in the free arc (3000K). Despite the possibility of applying different types of plasma generation in this process, the DC arc plasma system will be used to describe it.
The current state of the technique may be referenced in relevant documents such as:
1. CUBAS, A. L. V.; CARASEC, E. R.; DEBACHER, N. A.: SOUZA, I. G., Development of a DC-Plasma Torch for Decomposition on Organochlorine Compounds. Journal of the Brazilian Chemical Society, Br., v. 16, n. 3B, p. 531-534, 2005. 2. CUBAS, A. L. V.; CARASEC, E. R.; DEBACHER, N. A.; SOUZA, I. G. Use of Solid Phase Microextraction to Monitor gases Resulting from Thermal Plasma Pyrolysis. Chromatography, Germany, v. 60, n. ½, p. 85-88, 2004. 3. STALEY, L. Site Demonstration of Retech Plasma Centrifugal Furnace: The Use of Plasma to Vitrify Contaminated Soil Air & management Association, v. 42, n10, p. 1372-1376 1992. 4. BONIZZONI, G.: VASSALO, E. Plasma Physics and Technology: Industrial Applications. Vaccum. v. 64. p. 327-336 January 2002. 5. BOULOS, M.; FAUCHAIS, P.; PFENDER, E. Fundamentals and Applications. Thermal plasma, v. 1, 1995. 6. IWAO, T.; INABA T. Treatment of Waste by dc Arc Discharge Plasma. IEEE Transactions on Dielectrics and Electrical Insulation, v. 7, n o 5, p. 684-692. October 2000.
DESCRIPTION OF THE INVENTION
Molecular Conversion Processing of Greenhouse Gases is based on the conversion of greenhouse substances (molecules) through thermal plasma. The conversion of such molecules produces physical-chemical substances, which are totally different from the original ones, such as solid carbon and non-greenhouse gases.
The conversion process is carried out through a plasma torch, a plasma conversion chamber and an electrostatic filter. For a better explanation, we may use the example of carbon dioxide (CO 2 ), one of the main components of the greenhouse effect, whose conversion products by this process are solid carbon (C) and gaseous oxygen (O 2 ). The molecular conversion unity with a solid particle trap consists of a plasma conversion chamber and an electrostatic filter for the collecting of solid particles. The plasma conversion chamber is provided with a plasma torch that produces a plasma jet or ionized gas formed by discharge between the cathode and the anode.
The operation of thermal conversion processing of greenhouse gases is set up as follows. A conversion chamber is provided with a plasma arc torch that produces a plasma jet or ionized gas at temperatures around 10,000 K, formed by discharge between the cathode and the anode. The plasma torch is connected to a high-current electronic Source with a varied capacity, according to the gas or mixture of gases to be ionized. The equipment has a collector filter of solid particles. The molecular conversion process by thermal plasma follows two step. In the first step, the high temperature generated by ionized gas (plasma) breaks the chemical bonds of the molecules and forms highly reactive and unstable free radicals, which in a second step, during the cooling of the gaseous mixture, spontaneously recombine and form new substances of less molecular weight in an entropically favorable process.
Illustrated Description
To complement the verbal description of the invention, and for an easier comprehension of its characteristics, it is presented the FIG. 1 is presented as a mere illustration. The FIG. shows the extended diagram of the molecular conversion unity of greenhouse gases with a solid particle trap composed of modules: plasma torch (I); plasma conversion chamber (II); electrostatic filter (III); and high-current electronic source (IV).
Detailed Description of the Process and the Unit
The required equipment for the implementation of the “Thermal Conversion process of Greenhouse Gases” contains a High-Current Electronic Source (IV) to provide energy to the process, a Plasma Torch (II) and Plasma Conversion Chamber (II) for the mixture and pyrolytic conversion of the effluent gases, and an Electrostatic Filter (III) to separate the gaseous mixture and the solid particles.
The High-Current Electronic Source (IV) presents the following features. It offers power from 10 to 20 KW and has a high frequency electronic ignitor to establish the electric arc in order to form the plasma.
The plasma conversion may be carried out both directly and indirectly. In the direct way, the greenhouse gases are introduced between the electrodes with the torch maintenance gas. In the indirect way, the greenhouse gases are closely mixed with the plasma jet in the Conversion Chamber. In this Patent, the indirect process will be described. Here, the plasma conversion chamber (II) is formed by a plasma torch (I) of a non-transferred arc type and a tubular conversion chamber ( 7 ) of a direct flow type. The plasma conversion chamber (II) is the principal component of the molecular conversion. The mechanism of pyrolysis or molecular conversion takes place in the chamber, and for a better efficiency a close mixture between the gases that go into the chamber ( 1 ) and the plasma jet is necessary. For a better visualization of the modules (I, II, III, and IV), FIG. 1 presents an exploded view of the Molecular Conversion Unit of greenhouse gases. The direct current plasma torch (I) of a non-transferred arc has a central tungsten electrode which operates as a cathode (electron emitter) and a brass body ( 5 ), the anode, which operates as a electron collector. The torch must be water-cooled. The plasma is formed when gases, such as argon, nitrogen and air among others, flow between the two electrodes under a certain potential difference and high-current. The electric arc is first produced by a high frequency electronic ignitor (IV) that generates the first charge carriers. The REED Vortex or plasma jet is maintained by the high potency from the high voltage source (IV), stabilized by the gas flow between the electrodes which is ionized to form the previously-mentioned plasma jet at the outlet of the torch (I). These torches can reach temperatures of about 10,000 K in an appropriate environment able to molecularly convert any substance.
The Tubular Conversion Chamber (II) of Direct Flow comprises a surrounding tube ( 3 ) with a lateral gas feed tube and a central flame tube ( 7 ). The surrounding tube ( 3 ) is made of steel and it forms the real body of the Conversion chamber (II). The flame tube ( 7 ) is a cylinder comprising a free opening ( 8 ) at its back with a slight salience ( 9 ) to support itself in the interior of the surrounding tube ( 3 ). The torch (I) must be screwed into the frontal side of the flame tube ( 7 ). It is a high heat-resistant steel tube ( 7 ) that's needs to be completely surrounded by the surrounding tube. The flame tube ( 7 ) is placed exactly in the center of the enclosure surrounded by the tube ( 3 ). The flame tube ( 7 ) has a series of holes along its body which are functionally invariable and different from each other. When penetrating the chamber, the gases form a laminar flow, but when the gases enter through the different holes ( 10 ) they become a turbulent just after getting into the flame chamber ( 7 ). The turbulence is purposely provoked in order to guarantee a perfect mixture of gases with the REED Vortex or plasma jet.
The plasma conversion chamber (II) is coupled to an Electrostatic Filter (III). Some gases such as oxygen and nitrogen, as well as solid particles such as carbon and sulphur, will result from the molecular conversion. Thus, solid particle—carbon and sulphur resulting from CO 2 and SO x decomposition—will be removed from the gaseous flow in the electrostatic filter, similar to those that are available commercially. Electrostatic filters are the most appropriate for the gas outlet since they offer minimal resistance to the gaseous flow and are able to efficiently retain micro-pulverized material. The solid particles retained in the filter (III) will be removed to a container ( 11 ) placed at the bottom of this filter (III). At the outlet ( 2 ), the effluent gases should be free of greenhouse gases and solid particles.
The constructive form of the unit enables its installation next to the generator source. In addition, the unit presents a simple method of manufacturing of its elements. These characteristics make viable its large-scale industrial applications, enabling the reduction of pollutant gases such as carbon dioxide, one of the main greenhouse gases causing global warming. | 4y
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CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of PCT application No. PCT/EP02/07762, entitled “FLEXIBLE PRESS JACKET AND SHOE PRESS ROLL COMPRISING SUCH A FLEXIBLE PRESS JACKET”, filed Jul. 12, 2002.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a flexible press cover which is intended for a shoe press roll.
2. Description of the Related Art
A shoe press roll of this type is used for dewatering or calendering a moving fibrous web, in particular a paper or board web. The flexible press cover includes a plastic layer, preferably made of polyurethane and, as a strengthening element, a (“conventional”) reinforcement embedded in the plastic layer. The reinforcement can be formed as a woven fabric; however, preference is given to what is known as a laid fabric, which includes axially parallel longitudinal filaments and circumferential filaments wound in. The circumferential filaments can be wound into the plastic layer on the outer side of the longitudinal filaments (see EP 0330680=U.S. Pat. No. 5,134,010, PH 04378). However, the opposite arrangement is likewise possible (see WO 95/29293, Tamfelt).
In relation to the prior art, reference is made to the following further documents:
D1: DE 3546650 C2, (PH 04164A), D2: DE 29702362, (PH 10287), D3: DE 19633543 (PH 10368).
As is known, a shoe press roll includes a stationary supporting element. Rotatably mounted on the latter are two cover carrying disks for the flexible press cover. In addition, there is arranged on the supporting element a radially displaceable press shoe, which is able to press the revolving press cover against an opposing roll in order to form a press nip extended in the web running direction. It is important that the press cover and the cover carrying disks, together with the supporting element, bound a closed, liquid-tight internal space.
According to document D1, in order to achieve a liquid-tight connection between the press cover end region and one of the cover carrying disks, provision is made to bend over the end region radially inward and to press it against the outer end of the cover carrying disk with the aid of clamping elements.
This arrangement has been tried and tested in practice. However, it is disadvantageous in that a large number of recesses has to be provided in the edge zone of the press cover, between which recesses tongues remain. In some cases, difficulties also arise in achieving the most exact circularity of the press cover.
According to FIGS. 3 and 4 of document D2, attempts have been made to avoid the deformation of the press cover end region described in D1. Each of the two press cover end regions retains the normal cylindrical form, so that the production of recesses and tongues is dispensed with. Provision is made to clamp the cylindrical press cover end region in between an internal expandable (that is to say of enlargeable diameter) spreader ring and an outer ring. However, such an outer ring is frequently disruptive, since the replacement of a worn press cover by a new press cover is more awkward.
According to FIGS. 2 to 4 of document D3, an annular circumferential groove is provided in the outer circumferential surface of a cover carrying disk, into which groove the annular region of the press cover is pressed, specifically by way of a clamping band or by way of a plurality of turns of a high-strength filament or by way of a shrinkage ring. If a covering provided in accordance with FIG. 1 at document D3 is left out, then there is no disruptive outer ring. Nevertheless, this known solution has not been able to gain acceptance in practice.
What is needed in the art is a flexible press cover where the production of recesses and tongues in the press cover end region is superfluous, the mounting of the press cover end region on the respective cover carrying disk is easily achievable, the mounted press cover has good circularity and the outer circumferential surface of the press cover is free of fixing elements.
SUMMARY OF THE INVENTION
The present invention provides a flexible press cover with the following requirements satisfied:
a) the production of recesses and tongues in the press cover end region is superfluous; b) the mounting of the press cover end region on the respective cover carrying disk is able to be performed with the least possible effort; if the mounting operation is carried out within the papermaking machine, account must be taken of the fact that the mounting space which is available at the two roll ends is often very restricted; c) the most precise circularity of the finally mounted press cover should be achievable; d) the outer circumferential surface of the press cover should be free of fixing elements, for example outer rings.
The present invention comprises, in one form thereof, a flexible press cover which has an additional strengthening element in at least one of its two end regions. As a result, in the end region, the tensile strength and the tensile rigidity in the circumferential direction are increased with respect to that hitherto known in such a way that it is no longer necessary to clamp the press cover end region in between two components. Instead, the press cover according to the present invention is suitable to be fixed to the outer circumferential surface of a rotatable supporting element belonging to the cover carrying disk without the aid of an outer ring, a clamping band, clamping filament or the like. In the most beneficial case, the arrangement for fixing the press cover to the aforementioned supporting element is completely free of any kind of fixing elements which would be associated with the cover outer surface.
By virtue of the present invention, it is possible to achieve a number of advantages: the form of the press cover end region remains completely or at least approximately cylindrical. During the mounting of the press cover, deformation of the press cover end region is not necessary; the necessity of producing recesses and tongues is thus also dispensed with. The joining of the press cover end region to a radially outer part or region of the cover carrying disk can be carried out in the same way or at least in a very similar way as the joining of two metal components.
Thus, the mounting of the press cover on the cover carrying disks can be carried out in a simpler way than hitherto known, namely with less effort, so that, if required, even an unpracticed person can be entrusted with the mounting work. A further important advantage is that no outer ring (rotating with the press cover) is required. Likewise, the clamping elements required in accordance with D1 are omitted; this makes it easier to work in restricted conditions of space within the papermaking machine.
The press cover end region advantageously has a constant thickness, measured along axially parallel envelope lines. As a rule, on a finally mounted press cover, not only the outer circumferential surface but also the inner circumferential surface of the press cover end region (having the additional strengthening) are therefore cylindrical. However, a departure from this can be made if required. Specifically, it may be advantageous to design the inner circumferential surface of the press cover end region to be slightly conical, with an internal diameter which increases outward or inward. The fixing of the press cover end region to any kind of annular supporting element belonging to the cover carrying disk (or directly to the carrying disk) can be made easier hereby. In both cases, it can be advantageous to provide a supporting element of which the diameter can be enlarged, that is to say can be spread. However, the use of a non-spreadable ring is also possible, for example a mounting ring, which is inserted into a new press cover to be retrofitted outside the shoe press roll (see DE 101 38 527.7).
The present invention can be applied in flexible press covers with different conventional reinforcements, in particular with woven fabric or laid fabric reinforcement. Different embodiments of the additional strengthening are also specified; this can be formed as an additional or strengthened reinforcement. As an alternative to this or in addition, materials with a modulus of elasticity that is higher in the circumferential direction can be used. One further possibility is for a strengthening ring to be integrated into at least one of the press cover end regions. The object of all these measures is to reduce the extensibility in the circumferential direction of the press cover end region as compared with that hitherto.
Protection is also claimed for a complete shoe press roll having a flexible press cover formed in accordance with the present invention. In this case, at least one of the two cover carrying disks can be adapted in one way or another to the press cover end region formed in accordance with the present invention. Details are explained further below within the context of the figure description.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a partial longitudinal sectional view through a shoe press roll having an embodiment of a flexible press cover according to the present invention;
FIG. 2 is a partial view of an embodiment of a spreader ring belonging to the shoe press roll according to the present invention;
FIGS. 3-6 illustrate variants of FIG. 1 according to the present invention;
FIGS. 7-13 illustrate various modifications of the press cover end region in longitudinal section according to the present invention;
FIG. 14 illustrates an embodiment of the method of producing a press cover on the outer circumferential surface of a cast cylinder according to the present invention;
FIG. 15 illustrates an embodiment of the press cover produced in accordance with FIG. 14 in the finally mounted state; and
FIG. 16 illustrates a further variant of a shoe press roll having a flexible press cover according to the present invention.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIG. 1 , there is shown a shoe press roll, only one of the two end regions of flexible press cover 10 and its fixing to a rotatable cover carrying disk 20 . The latter is mounted in a known way on a supporting element, not visible, by way of a rolling contact bearing 21 . Likewise not illustrated is a press shoe, using which press cover 10 can be pressed against an opposing roll. These and further known details of a shoe press device can be seen, for example, from DE 19522761 (PH 10178).
Press cover 10 is substantially composed of a plastic layer 30 , for example of polyurethane, with a conventional reinforcement embedded therein as a strengthening elements; the reinforcement includes, axially parallel longitudinal filaments 31 and circumferential filaments 32 wound thereon. The thickness d of press cover 10 is chosen such that grooves or blind holes 33 can be provided within the pressing zone P. In the end region E, press cover 10 has substantially the same thickness d as in pressing zone P. In end region E, as additional strengthening (that is to say in addition to conventional reinforcement 31 , 32 ), additional circumferential filaments 34 of the highest possible tensile strength and tensile rigidity (high modulus of elasticity) are embedded in plastic layer 30 .
According to the present invention, circumferential filaments 34 form an additional reinforcement, produced from high-strength plastic or metal filaments or wires. As compared with circumferential filaments 32 of the conventional reinforcement, the additional circumferential filaments or wires 34 can have a larger filament diameter and/or be formed from a material which has a higher tensile strength and, in particular, a higher modulus of elasticity (e.g. Kevlar). However, it is also possible to choose the same diameter and/or the same material for filaments 32 and 34 , preferably a material with a relatively high modulus of elasticity. In addition, the plastic layer can be formed from a material with an increased modulus of elasticity. Between end region E and pressing zone P, press cover 10 can have a zone of lower thickness, in order to increase its flexibility precisely where increased deformation takes place during operation.
Cover carrying disk 20 includes an integrally molded collar 22 and an extension ring 23 screwed to the latter. Collar 22 and ring 23 engage around rolling contact bearing 21 and, on their outer side, bear an axially displaceable clamping ring, which is formed as an annular piston 24 . The three aforementioned components 22 , 23 and 24 are shaped in such a way that an annular space 25 , to which a pressurized medium can be applied, is formed between them. As a result, annular piston 24 can be displaced outward hydraulically or pneumatically parallel to the roll axis. Sealing rings 26 are used to seal off the annular space 25 .
In order to connect press cover 10 to cover carrying disk 20 , spreader ring 27 is provided. The latter has a cylindrical outer circumferential surface, provided with recesses if required, which engages in the cylindrical inner circumferential surface of the press cover end region E. Spreader ring 27 has a conical inner circumferential surface, which interacts with a conical outer circumferential surface of annular piston 24 . In the event of axial displacement of annular piston 24 (to the left in FIG. 1 ), spreader ring 27 (which bears axially on cover carrying disk 28 ) is widened, and therefore a secure, liquid-tight connection is made between press cover 10 and cover carrying disk 20 . By virtue of additional reinforcement 34 , an external clamping link is no longer required in the press cover end region.
The axial displacement of annular piston 24 can also be carried out with the aid of screws (indicated at 28 ). Screws 28 of this type can also be used for the axial fixing of annular piston 24 after the annular piston has been displaced hydraulically or pneumatically. FIG. 2 shows spreader ring 27 from the outside. This ring is given its ability to spread by slots 29 machined in alternately from both sides, in which a highly elastic filler is provided, in order that the necessary hermetic sealing of the roll internal space is ensured.
FIG. 3 differs from FIG. 1 in that, in end region E on press cover 10 ′, provision is made for bead 30 A projecting radially inward, which fits into a turned recess in spreader ring 27 ′. In this way, the accuracy of the axial fixing of press cover 10 ′ to carrying disk 20 is increased.
Press cover 10 A of the exemplary embodiment illustrated in FIG. 4 is similar to that of FIG. 1 ; only length E′ of the press cover end region has been enlarged somewhat, corresponding to the greater axial length of spreader ring 27 A. Cover carrying disk 20 A again has collar 22 A to accommodate rolling contact bearing 21 . Between collar 22 A and spreader ring 27 A there is a simple clamping ring 24 A. The latter is displaced axially in the outward direction merely with the aid of screws 28 , enlarging the outer diameter of the spreader ring with its conical outer. circumferential surface, which interacts with a conical inner circumferential surface of spreader ring 27 A, in order to produce a secure connection to press cover 10 A. Integrally molded on spreader ring 27 A is collar 27 B, which again makes the accurate axial fixing of press cover to carrying disk 20 A easier.
In a shoe press roll according to the present invention, both ends of the roll can be constructed in accordance with FIG. 1 . Another possibility is for one end of a shoe press roll to be configured in accordance with FIG. 1 or FIG. 3 , but, on the other hand, for the other end of the roll to be figured in accordance with FIG. 4 or in accordance with FIG. 5 or 6 described below.
Press cover 10 B of the exemplary embodiment illustrated in FIG. 5 differs from press cover 10 A of FIG. 4 only in the fact that the inner circumferential surface in the end region is not continuously cylindrical but is slightly conical a short distance from the outside, with an internal diameter that decreases from the outside toward the inside.
This makes it easier to insert mounting ring 40 , which has a corresponding conical outer circumferential surface. The insertion of this ring 40 (and the fixing of the same in press cover 10 B, for example by way of adhesive) is preferably carried out outside the shoe press roll, that is to say before the removal of a press cover that has worn and is to be replaced. For fixing mounting ring 40 bearing press cover 10 B to cover carrying disk 20 B, the following is provided: the outer circumferential surface of cover carrying disk 20 B is offset at 41 . The inner circumferential surface of strengthening ring 40 has a corresponding offset, in the example illustrated, a relatively small internal diameter D being followed by a larger internal diameter in the axial direction from the inside to the outside. In this way, press cover 10 B, together with pre-mounted mounting ring 40 , can be pushed onto cover carrying disk 20 B in the direction of the arrow P over the entire (not illustrated) stationary supporting element. This is possible by virtue of the fact that the aforementioned relatively small internal diameter D of ring 40 is still somewhat larger than the external dimensions of the stationary supporting element, including the press shoe and further accessories. In order to screw ring 40 to cover carrying disk 20 B, the following is provided: bush 42 is rotatably mounted in a bore in cover carrying disk 20 B. Integrally molded at the inner end of bush 42 is a nose flange 43 ; a radial pin 44 is inserted into the outer end. In the illustrated position of bush 42 , the nose of nose flange 42 acts on the inner end of ring 40 . However, as a result of rotation of bush 42 , the nose permits the strengthening ring to pass when inserted in the direction of the arrow P. In order to fix mounting ring 40 (together with press cover 10 B) to cover carrying disk 20 B with the aid of the aforementioned nose flange 43 , a screw 28 is provided. A plurality of such arrangements are distributed over the circumference of cover carrying disk 20 B.
FIG. 6 shows a simplified alternative to FIG. 5 . Mounting ring 40 ′ here has a smooth inner circumferential surface (without offset 41 shown in FIG. 5 ); in addition, bush 42 has been omitted. Mounting ring 40 ′ is screwed to cover carrying disk 20 ′ by way of simple studs 45 . In this design, however, a smaller internal diameter D′ of mounting ring 40 ′ will generally be needed than in FIG. 4 . In order that, as the press cover is drawn in, mounting ring 40 ′ can nevertheless pass the stationary supporting element with its accessories, it may be necessary to arrange some of these accessories such that they can move on the supporting element; see the parallel patent application DE 101 38 527.7
For fixing press cover 10 C to mounting ring 40 ′, the following is provided: the mounting ring has a conical outer circumferential surface that tapers in the outward direction. In addition, in press cover end region E″, circumferential filaments 32 A and/or 34 A are wound in with increased prestress, so that end region E″ likewise tapers conically in the outward direction. Press cover 10 C is fixed onto mounting ring 40 ′ in a manner similar to the fixing of a vehicle tire to its rim. The press cover design with circumferential filaments wound in under increased prestress can also be combined with a mounting ring whose outer circumferential surface is cylindrical.
FIG. 7 shows press cover 11 which is modified with respect to FIG. 1 and whose conventional reinforcement (differing from FIG. 1 ) has axially parallel longitudinal filaments 35 arranged outside circumferential filaments 32 (corresponding to WO '293). As additional reinforcement, circumferential filaments 36 are provided, which are preferably wound onto the reinforcement 32 , 35 from the inside. As an alternative to this or in addition, in order to strengthen the press cover end region further, circumferential filaments 36 ′ which are wound onto the reinforcement 32 , 35 from the outside can be provided.
Press cover 12 illustrated in FIG. 8 has, as reinforcement, a woven fabric 37 . As additional reinforcement of the press cover end region, circumferential filaments 38 are provided, which are wound onto woven fabric 37 from the outside. Alternatively to this or additionally, circumferential filaments 38 ′ arranged radially on the inside can be provided.
In the exemplary embodiments according to FIGS. 7 and 8 , both press cover end regions can be designed identically. By contrast, the variant illustrated in FIG. 9 can be provided only at one of the two press cover ends. This results from the production method according to EP 0330680 (production of the press cover on the outer side of a cast cylinder). In detail, FIG. 9 shows a press cover 13 whose reinforcement 31 , 32 corresponds to that of the press cover 10 illustrated in FIG. 1 . The illustrated end region of press cover 13 has, in a way similar to FIG. 3 , a thickening 30 A projecting radially inward. Located in this is an additional reinforcement, which can be formed as a woven fabric or (as illustrated) as a laid fabric, including axially parallel longitudinal filaments 39 and circumferential filaments 39 ′ wound thereon. In addition, a thickening (not illustrated) projecting radially outward can be provided, similar to that of FIG. 1 or 3 .
FIG. 10 shows a press cover 50 according to the present invention whose end region has no thickening. Here, the additional strengthening is formed by circumferential filaments 32 ′ being wound more densely in the end region than circumferential filaments 32 located outside the end region. Circumferential filaments 32 and 32 ′ can include the same material. As an alternative to this, circumferential filaments 32 ′ can also be formed from a material with an increased modulus of elasticity. In addition, in the end region, plastic layer 30 can be produced from a material with an increased modulus of elasticity.
FIGS. 11 to 15 show embodiments of the press cover according to the present invention in which a strengthening ring (of plastic or metal) is integrated into the end region of the press cover as additional strengthening. According to FIG. 11 , the thickness d of the axially outer region 52 of strengthening ring 51 is substantially the same as or greater than the thickness of end region E of press cover 10 of FIG. 1 . The axially inner region 53 is substantially thinner and overlaps the end of press cover 54 , initially produced in the conventional way (EP'680), with its conventional reinforcement 31 , 32 . Ring 51 is fixed by casting on an additional plastic layer 55 and winding in additional circumferential filaments 56 at the same time. Press cover 54 is fixed to the cover carrying disk in the same way as in FIG. 1 or 4 or by way of screws which engage directly in strengthening ring 51 in the axial direction (see threaded hole 59 ).
FIG. 12 differs from FIG. 11 in that strengthening ring 51 A is thinner in its axially outer region than the thickness d of the finished press cover end region, and in that it is sheathed over its entire length by the additional plastic layer 55 A with additional circumferential filaments 56 .
FIG. 13 shows the end region of a press cover 60 produced in accordance with WO '293 with strengthening ring 61 . Illustrated schematically is a cast cylinder 62 with its inner circumferential surface 63 . Firstly, during the production of the press cover 60 , strengthening ring 61 fixed to cast cylinder 62 and is used to clamp the longitudinal filaments 64 on. Plastic layer 65 is then cast, circumferential filaments 66 simultaneously being wound from the inside onto longitudinal filaments 64 and strengthening ring 61 . In order to fix press cover 60 to a cover carrying disk (not illustrated), strengthening ring 61 has flange 67 projecting radially inward. Alternatively, flange 68 projecting radially outward could be provided.
FIG. 14 shows the production method of a press cover 70 with strengthening rings and 71 and 72 . The production method similar to that of EP '680, with a cast cylinder 73 on whose circumferential outer surface the production takes place. Differing from EP '680, instead of clamping rings, strengthening rings 71 and 72 are provided, which are used initially to clamp longitudinal filaments 74 on and which, after plastic layer 75 has been cast on and circumferential filaments 76 have simultaneously been wound on, remain a constituent part of press cover 70 . The secure fixing of strengthening rings 71 and 72 in press cover 70 is achieved by the longitudinal filaments 74 (as disclosed by EP '680) being drawn in a meandering fashion through strengthening rings 71 , 72 and then being tensioned, additionally by the fact that circumferential filaments 76 are wound onto the strengthening rings with a certain prestress. FIG. 14 also shows how casting nozzle 77 moves from one end of cast cylinder 73 to the other during the casting operation, while the cylinder rotates at the same time.
One strengthening ring 71 has flange 71 a projecting radially inward, which bears on one end of cast cylinder 73 . The other strengthening ring 72 has flange 72 a projecting radially outward, in which clamping screws 78 engage in order to tension longitudinal filaments 74 .
FIG. 15 shows the press cover 70 produced in accordance with FIG. 14 in the finished state mounted on cover carrying disks 79 and 80 . In this case, flanges 71 a and 72 a are used for fixing the press cover to the carrying disks, in each case with the aid of screws 81 , 82 . Each of the two strengthening rings 71 , 72 is centered on an outer circumferential surface of its cover carrying disk. In order to make it easier to draw in press cover 70 in the axial direction (arrow P), the diameter of the outer circumferential surface of carrying disk 79 on the left (in FIG. 15 ) is smaller than that of the right-hand carrying disk 80 . Accordingly, cast cylinder 73 in FIG. 14 is offset slightly at 83 .
In the case of press cover 14 illustrated in FIG. 16 (whose conventional reinforcement is not illustrated), additional strengthening is formed as an end section 16 of the press cover which is folded inward (or turned over). Additional reinforcement 15 is provided therein. As FIG. 16 shows, the inner circumferential surface of the inwardly folded end section 16 is conical with an internal diameter increasing in the inward direction. As a result, press cover 14 is fixed to cover carrying disks 20 C and 20 D in a manner similar to the fixing of a vehicle tire to a rim. One press cover end section preferably rests directly on cover carrying disk 20 D, which has a corresponding conical outer circumferential surface. The other end section rests on clamping ring 17 , which likewise has a corresponding conical outer circumferential surface and which can be displaced in an axially parallel manner on cover carrying disk 20 C. A plurality of ring segments 18 can be inserted into cover carrying disk 20 C in the radial direction from the outside to the inside. Through said segments there extend screws 19 , using which the press cover end section can be clamped in between clamping ring 17 and ring segments 18 .
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | 4y
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This is a continuation of copending application Ser. No. 134,030, filed on Dec. 17,1987, now abandoned.
BACKGROUND OF THE INVENTION
Hunters and trap shooters alike have long been faced with the problem of carrying a firearm in the field. Slings and straps previously available have proven too cumbersome for carrying rifles and shotguns, requiring, as they do, a relatively long time to bring a gun from the carrying position to a ready position. At the same time, carrying or holding a firearm for extended distances is tiring.
SUMMARY OF THE INVENTION
The present invention provides a gun caddy which permits easy carrying of a rifle or shotgun while retaining its accessibility.
Specifically, the instant invention provides a gun caddy comprising a belt having a width of about from 3/4 to 3 inches, the belt being formed to provide an interior base and an exterior loop, the exterior loop being about from one to three inches from the base, and a pocket depending from the interior base and the exterior loop, the pocket being about from one to five inches deep and about from three to eight inches wide.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a front perspective view of a gun caddy of the present invention.
FIG. 2 is a side view of a gun caddy of the present invention.
FIG. 3 is a top view of a gun caddy of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention can be best understood by reference to the drawings, in which FIG. 1 is a front perspective view of a gun caddy of the invention. There, belt 1 has an interior base portion 2 and exterior loop 3. The belt is generally about from 3/4 to 3 inches wide, an preferably about two inches wide. The exterior loop can be formed with fixed rivets or preferably through the use of adjustable cleat 4. For overall stability of the caddy, the spacing between the edge of the pocket and the cleats or clasp that define the loop should be less than about 1/2 inch on either side. The belt is adjusted to provide a spacing of about from one to three inches between the base portion and the exterior loop, and preferably about from 11/2 to 2 inches. This spacing permits the easy insertion of the butt of the firearm. The use of an adjustable cleat, as shown, permits the installation of the caddy on the user's right or left side, as desired. Typically the belt will be provided with a positive clasp.
The pocket 5, which has a generally U-shaped configuration, depends from the exterior loop and the interior base portion of the belt through loops 6 sewn in the pocket. The pocket can be about from one to eight inches deep, and preferably about from four to six inches deep. Those pockets having a greater depth provide increased stability for the butt of the gun, and preferably have side walls 7 and 7a extending for a distance of at least about one inch from the bottom of the pocket. Those pockets having side walls or a shallower depth prevent the butt of the rifle or shotgun from slipping through the sides of the pocket while it is being carried. The pocket is generally about from four to six inches wide, and is preferably prepared from a woven or knitted elastic fabric. It has been found particularly beneficial to form the pocket from fabric that is elastic in substantially only the vertical direction as the caddy is worn. A particularly satisfactory fabric is one having an elasticity of about from 75% 100% in the warp direction and less than about 20% in the weft direction.
The gun caddy of the invention is further illustrated in FIG. 2, which is a side view of the caddy. In that Figure, front panel 5a of the pocket is shown to be continuous with back panel 5b, and are joined by side walls 7. The side walls, when used, should extend at least about one inch from the bottom of the pocket, and provide additional protection, particularly in deeper pockets, against the butt of the rifle slipping out through the sides.
FIG. 3 is a top view of the caddy, showing the spacing between the interior base 2 of the belt and the exterior loop 3. | 4y
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application Ser. No. 10/440,935 filed May 19, 2003, which issued as U.S. Pat. No. 6,848,495 on Feb. 1, 2005.
BACKGROUND OF THE INVENTION
The present invention relates generally to a method of manufacturing a laminated rotor for a motor. More specifically, the present invention is related to methods of manufacturing a laminated rotor with laminations having a desired rotor bridge thickness prior to the assembly of the laminated rotor core.
A squirrel cage rotor for use in an induction motor has a rotor core and a rotor cage that extends through the rotor core and is connected together at each end of the rotor core by end rings. The rotor core is typically made of a magnetic material such as iron or steel and the rotor cage is typically made of an electrically conductive material such as copper, aluminum or an aluminum alloy. The rotor core has a substantially cylindrical shape with a longitudinally extending central bore to receive the shaft of the motor and a plurality of longitudinally extending rotor slots or apertures, which rotor slots may be slightly skewed, to receive corresponding rotor bars of the rotor cage. A laminated rotor core is commonly manufactured or formed by stacking or assembling a plurality of discs or laminations of the magnetic material on top of each other until the desired substantially cylindrical shape is obtained. During the stacking or assembling process, the laminations are also aligned or oriented into their proper position. Alternatively, the rotor core can be manufactured from a single piece of the magnetic material, but this technique is less common.
Each lamination in the rotor core is formed or extruded to a pre-selected thickness, shape and configuration. The pre-selected configuration of the laminations includes an aperture for the central bore, a plurality of apertures for the rotor slots positioned equidistantly about the central bore and a predetermined bridge thickness, which bridge thickness is defined as the radial distance between the outer circumference of the lamination and the aperture for the rotor slot. The dimensioning of the bridge thickness is important because the bridge thickness of the rotor is related to the motor's performance, wherein a thinner bridge thickness provides better performance. The pre-selected configuration of the lamination can also include other features as needed. As the laminations are stacked to form the rotor core, they are aligned and/or oriented into an appropriate position to form substantially continuous apertures in the rotor core and, if necessary, other desired features of the rotor core.
Next, the rotor cage is manufactured or formed by positioning or disposing a rotor bar into each of the plurality of rotor slots in the rotor core, which rotor bars extend to at least the ends of the rotor slots, and connecting the adjacent ends of the rotor bars to each other with an end ring. In one technique, the stacked laminations forming the rotor core can be welded together and/or axially compressed to fix their position and can then be placed in a mold. Once in the mold, the rotor bars, and possibly the rings, can then be formed by die casting or injection molding molten aluminum (or other suitable material), under high pressure, directly into the rotor slots and possibly into molds for the end rings. Alternatively, the rotor bars can be placed or positioned in the rotor slots using any suitable technique and can then be connected together by attaching or connecting a ring to each end of the rotor bars using any suitable technique such as brazing. It should be noted that if the end rings are not cast during the casting process, the end rings can be connected or attached using the brazing technique described above.
One potential problem with casting the rotor bars into the laminated rotor core is that additional steps have to be taken to prevent the molten casting material, e.g. molten aluminum, from leaking or seeping between the laminations. To prevent the molten casting material from leaking or seeping between the laminations, the laminations are typically formed or extruded with a greater than desired outer diameter or bridge thickness and are welded together or compressed axially as discussed above. When these additional steps are performed, both the inner diameter and outer diameter of the laminated rotor have to be subsequently machined or processed after the casting process to obtain the desired inner diameter, outer diameter and bridge thickness for the laminated rotor.
Therefore, what is needed are techniques for manufacturing a laminated rotor with laminations having an outer diameter and/or bridge thickness that restricts the molten material cast into the rotor core from leaking or seeping out between the laminations during the casting process.
SUMMARY OF THE INVENTION
One embodiment of the present invention is directed to a method of manufacturing a laminated rotor for a motor. The method of manufacturing including the step of providing a plurality of laminations. Each lamination of the plurality of laminations having a plurality of rotor slots and a preselected bridge thickness. The preselected bridge thickness is selected to provide optimal motor performance. Next, the plurality of laminations are assembled into a laminated rotor core and both axial and radial forces are applied to the laminated rotor core to secure the laminated rotor core in a fixed position. Finally, a molten material is introduced into each of the plurality of rotor slots to form a plurality of rotor bars, wherein the axial and radial forces applied to the laminated rotor core prevent the molten material from leaking between assembled laminations.
Another embodiment of the present invention is directed to a method of manufacturing a laminated rotor for a motor. The method of manufacturing includes the step of providing a plurality of laminations. Each lamination of the plurality of laminations having a first planar surface, a second planar surface opposite the first planar surface and a bridge thickness providing optimal motor performance. Each lamination of the plurality of laminations including a plurality of rotor slots, a plurality of countersink portions disposed in the first planar surface, and a plurality of collar portions disposed on the second planar surface. Each rotor slot of the plurality of rotor slots has a corresponding countersink portion and a corresponding collar portion. The next step is assembling the plurality of laminations into a laminated rotor core, wherein the plurality of collar portions of one lamination fit in the plurality of countersink portions of an adjacent lamination. A force is applied to the laminated rotor core to secure the laminated rotor core in a fixed position. Finally, a molten material is cast into each of the plurality of rotor slots to form a plurality of rotor bars, wherein the countersink portion and the collar portion of adjacent laminations prevent the molten material from leaking between assembled laminations.
A further embodiment of the present invention is directed to a rotor core lamination for a laminated rotor. The lamination includes a substantially cylindrical body having a central axis and an outer circumference. The substantially cylindrical body also has a first planar surface and a second planar surface opposite the first planar surface. The lamination also includes a plurality of apertures disposed between the central axis and the outer circumference of the substantially cylindrical body. The plurality of apertures extend from the first planar surface to the second planar surface. The lamination further includes a plurality of channels disposed in the first planar surface of the substantially cylindrical body and a plurality of collar portions extending away from the second planar surface of the substantially cylindrical body. Each channel of the plurality of channels being disposed adjacent to a corresponding aperture and each collar portion of the plurality of collar portions being disposed adjacent to a corresponding aperture. Finally, each collar portion of the plurality of collar portions is configured and disposed to fit within a corresponding channel of the plurality of channels of another lamination upon assembly of the lamination in the laminated rotor.
One advantage of the present invention is that a laminated rotor can be manufactured with laminations having the desired outer diameter and/or bridge thickness without the need for a subsequent machining operation.
Another advantage of the present invention is that the rotor manufacturing process is more economical and efficient because expensive and laborious machining processes are eliminated.
Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a perspective view of a laminated rotor core for use with the present invention.
FIG. 2 illustrates a top view of a lamination from the laminated rotor core of FIG. 1 .
FIG. 3 illustrates schematically the force applying members in one embodiment of the present invention.
FIG. 4 illustrates schematically the force applying members in another embodiment of the present invention.
FIG. 5 illustrates a top view of a lamination in another embodiment of the present invention.
FIG. 6 illustrates a cross-sectional view of the lamination of FIG. 5 taken along line VI—VI in FIG. 5 .
FIG. 7 illustrates a cross sectional view of several laminations of FIGS. 5 and 6 assembled together.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a laminated rotor core 100 for use with the present invention. The laminated rotor core 100 is preferably used in a squirrel cage rotor of an induction motor for a compressor. The laminated rotor core 100 is formed or assembled by stacking a plurality of laminations 102 . The number of laminations required to assemble the laminated rotor core 100 is dependent upon the thickness of the laminations 102 and the desired height of the laminated rotor core 100 . In one embodiment of the present invention, the thickness of the laminations can range from about 0.015 inches to about 0.025 inches and is preferably 0.022 inches thick for a standard application and 0.018 inches thick for a “low loss” application.
FIG. 2 illustrates a top view of a lamination 102 . Each lamination 102 that is assembled into the laminated rotor core 100 preferably has a central aperture or bore 104 . The central bore 104 of the laminated rotor core 100 is configured to receive the shaft of the motor upon complete assembly of the motor. In addition, each lamination 102 preferably has a plurality of rotor slots or apertures 106 . The rotor slots 106 are preferably completely enclosed by the outer circumference of the laminated rotor core 100 , i.e., they are closed rotor slots. It is to be understood that apertures 106 , while being referred to as rotor slots and shown as circular apertures in the Figures can have any desired shape including oval, circular, rectangular, irregular or any other suitable shape. The plurality of rotor slots 106 are positioned circumferentially about the center axis A of the lamination 102 . The plurality of rotor slots 106 are preferably positioned equidistant and/or equiangular to one another about the axis A. The shape, number and size of the rotor slots 106 are dependent on the particular configuration of the motor and rotor cage used. In one embodiment of the present invention, the number of rotor slots (and bars) can range from about 20 to about 40 and is preferably 34 bars for a high torque application and 28 bars for a high performance application.
Furthermore, each rotor slot 106 is positioned a distance “d” from the outer circumference of the lamination 102 . The distance “d” corresponds directly to the bridge thickness of the lamination 102 and laminated rotor core 100 . To obtain optimal motor performance, the bridge thickness “d” should be as small or thin as possible while still maintaining the structural integrity of the rotor during operation of the motor. For example, for a laminated rotor core 100 having an outer diameter of 2.6 inches, the bridge thickness is preferably between about 0.01 inches and about 0.02 inches wide. The preferred bridge thickness “d” can vary depending on the configuration and size of the motor. Finally, it is to be understood that the lamination 102 can include additional features which are not shown for simplicity.
The laminations 102 are preferably formed from a magnetic material such as iron or steel by an extrusion or pressing operation of one or more steps. Once the extrusion operation is complete, the laminations 102 will preferably have a top view similar to the top view of FIG. 2 . After the laminations 102 are extruded, they are stacked or assembled to obtain the laminated rotor core 100 . During the assembly operation, the laminations 102 are preferably aligned and/or oriented to obtain a central bore 104 which extends substantially longitudinally and coaxially through the laminated rotor core 100 and to obtain rotor slots 106 which extend substantially longitudinally and coaxially through the laminated rotor core 100 , i.e., the rotor slots 106 have a skew of 0 degrees. In another preferred embodiment, the laminations 102 can be oriented to obtain rotor slots 106 that extend longitudinally through the laminated rotor core 100 with a skew of 2-15 degrees and preferably between about 4-12 degrees. The embodiment of the laminated rotor core 100 that does not have a skew of the rotor slots 106 can be used for a three phase application and the embodiment of the laminated rotor core 100 that has a skew of the rotor slots 106 can be used for a single phase application.
In a preferred embodiment of one process of the present invention, laminations 102 are formed or extruded with a bridge thickness “d” that provides for optimal performance of the motor, and are then assembled together to form the laminated rotor core 100 . The laminated rotor core 100 is placed in a mold of a casting or injection molding apparatus (not shown). Once the laminated rotor core 100 is placed in the mold, both radial forces and pressure and axial forces and pressure are applied to the laminated rotor core 100 by the mold and/or casting or injection molding apparatus to hold or secure the laminated rotor core 100 in position for the casting or injection molding operation and to prevent the molten material used in the casting or injection molding process, preferably aluminum or aluminum alloy, from leaking or seeping between the stacked laminations 102 of the laminated rotor core 100 . Upon being secured in the mold of the casting or injection molding apparatus, the laminated rotor core 100 is now ready for the commencement of the casting or injection molding operation to manufacture some or all of the rotor cage. The casting or injection molding apparatus includes a system or device for casting, injecting or introducing the rotor bars into the rotor slots 106 of the laminated rotor core 100 and preferably a mold or cast for casting, injecting or introducing end rings to connect the ends of the rotor bars. The application of both the radial and axial forces to the laminated rotor core 100 during the casting or injection molding operation prevents the leaking or seeping of the molten material between the stacked laminations 102 even though the laminations 102 and laminated rotor core 100 have a “thin” bridge thickness “d” for optimal performance of the motor.
FIGS. 3 and 4 illustrate schematically two embodiments for applying the axial and radial forces to the laminated rotor core 100 . In FIG. 3 , the laminated rotor core 100 is held in position by one or more axial force members 302 and one or more radial force members 304 . The axial force members 302 are configured and disposed to apply an axial force F A , as shown in FIG. 3 , to the top and bottom of the laminated rotor core 100 to axially compress the laminated rotor core 100 and laminations 102 without interfering with the casting operation. In addition, the axial force members 302 are configured and disposed to preferably apply the axial force F A about substantially the entire circumference of the laminated rotor core 100 , although the axial force F A can be applied to selected segments of the laminated rotor core 100 . Similarly, the radial force members 304 are configured and disposed to apply a radial force F R , as shown in FIG. 3 , to the sides or outer perimeter of the laminated rotor core 100 to radially compress the laminated rotor core 100 and laminations 102 without interfering with the casting operation. In addition, the radial force members 304 are configured and disposed to preferably apply the radial force F R about substantially the entire outer perimeter of the laminated rotor core 100 , although the radial force F R can be applied to selected segments of the laminated rotor core 100 .
In FIG. 4 , the laminated rotor core 100 is held in position by two or more “L”-shaped force members 402 . The “L”-shaped force members 402 are configured and disposed to apply both an axial force F A , as shown in FIG. 4 , to the top and bottom of the laminated rotor core 100 to axially compress the laminated rotor core 100 and laminations 102 without interfering with the casting operation and to apply a radial force F R , as shown in FIG. 4 , to the sides or outer perimeter of the laminated rotor core 100 to radially compress the laminated rotor core 100 and laminations 102 without interfering with the casting operation. In addition, the “L”-shaped force members 402 are configured and disposed to preferably apply the axial force F A and the radial force F R about substantially the entire circumference and outer perimeter of the laminated rotor core 100 , although the axial force F A and the radial force F R can be applied to selected segments of the laminated rotor core 100 .
In this embodiment of the present invention, any suitable type of casting or injection molding apparatus and/or mold can be used for the casting or injection molding of the rotor cage so long as the casting or injection molding apparatus and/or mold can apply both an axial force or pressure and a radial force or pressure to the laminated rotor core at the same time during the casting operation. Finally, while not described herein, the remaining process steps for the manufacture of the rotor and motor would be completed as is well known in the art.
In another preferred embodiment of the present invention, the laminated rotor core 100 is assembled using the laminations shown in FIGS. 5-7 . FIG. 5 illustrates a top view of the lamination 500 of this embodiment of the present invention. As shown in FIG. 5 , lamination 500 has a central bore 502 and a plurality of rotor slots 504 , similar to the lamination 102 described above. However, in contrast to the lamination 102 of FIG. 2 , the lamination 500 , as shown in greater detail in FIG. 6 , has a countersink or groove portion 506 and a collar or lip portion 508 adjacent to each rotor slot 504 . The countersink portion 506 is preferably disposed on one planar side of the lamination 500 and is preferably a channel or groove in the side of the lamination 500 that is open to the rotor slot 504 and substantially circumferentially encloses or surrounds the rotor slot 504 . The collar portion 508 is disposed opposite the countersink portion 506 on the other planar side of the lamination 500 and is preferably an extension or projection extending from the other planar side and circumferentially enclosing or surrounding the rotor slot 504 . Preferably, the countersink portion 506 and the collar portion 508 are substantially coaxial to the center axis of the rotor slot 504 .
As shown in FIG. 7 , when assembling the laminated rotor core 100 with laminations 500 , the collar portions 508 of each lamination 500 are preferably configured to mate with or fit in the countersink portions 506 of adjacent laminations 500 , such that an interference fit or connection is formed between the two. The countersink portions 506 and the collar portions 508 are preferably configured and disposed on the lamination 500 such that a substantially cylindrical rotor slot 504 is produced as shown in FIG. 7 , which rotor slot 504 is similar to the rotor slot 106 of lamination 102 . When assembled, the countersink portion 506 and the collar portion 508 form a liquid barrier between a spacing 510 between the laminations 500 and the rotor slots 504 . The liquid barrier formed by the countersink portion 506 and the collar portion 508 is used to prevent the molten material used to cast the rotor bars from leaking or seeping between the laminations 500 during the casting operation.
While the countersink portion 506 and the collar portion 508 are shown with surfaces that are substantially parallel or perpendicular to the central axis of the rotor slot 504 , the surfaces of the countersink portion 506 and the collar portion 508 can have any type of surface including angled or curved surfaces so long as the countersink portion 506 and the collar portion 508 can be fit together to form an interference fit and the rotor slot 504 is not altered. Furthermore, the depth of the countersink portion 506 is substantially equal to the height of the collar portion 508 . However, it should be noted that slight differences in the depth and height of the countersink portion 506 and the collar portion 508 may be accommodated for in the casting operation when the laminated rotor core 100 is axially compressed. In a preferred embodiment of the present invention, the height of the collar portion 508 (or the depth of the countersink portion 506 ) is between about 10% and about 30% of the thickness of the lamination.
The process of manufacturing a laminated rotor core 100 with laminations 500 will now be described. To begin, laminations 500 are produced by an extrusion or stamping process with a bridge thickness “d” that provides for optimal performance of the motor, and then the laminations 500 are assembled together to form a laminated rotor core 100 . The laminated rotor core 100 is positioned in a mold of a casting or injection molding apparatus (not shown) and secured or held in place. The securing and holding of the laminated rotor core 100 can be accomplished using techniques that are known in the art or by the technique described above that applies both radial forces and pressure and axial forces and pressure are applied to the laminated rotor core 100 . Upon being secured in the mold of the casting or injection molding apparatus, the laminated rotor core 100 is now ready for the commencement of the casting or injection molding operation to manufacture some or all of the rotor cage. The casting or injection molding apparatus includes a system or device for casting, injecting or introducing the rotor bars into the rotor slots 504 of the laminated rotor core 100 and preferably a mold or cast for casting or injection molding end rings to connect the ends of the rotor bars. The presence of the countersink portions 506 and the collar portions 508 form a barrier in the rotor slots 504 to prevent the leaking or seeping of the molten material from between the stacked laminations 502 even though the laminations 502 and laminated rotor core 100 have a “thin” bridge thickness for optimal performance of the motor.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | 4y
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BACKGROUND OF THE INVENTION
This invention involves a self-lubricating ocular prosthesis and more particularly a prosthetic eye that is a source of lubricant and bactericide coupled with the method of use and method of manufacture of the prosthetic device.
For the person who has lost an eye due to injury, disease, or genetic defect, the art of the Ocularist has long been available to supply an ocular prosthesis including a prosthetic eye that almost exactly matches the person's natural eye. The ocular prosthesis may be necessary following an enucleation, an evisceration or the absence of an eye due to a congenital birth defect. In the vast majority of cases, an orbital implant is surgically implanted onto which the prosthetic eye is inserted. The artificial eye is cast from polymerized polymethacrylate resins using techniques well known in the art. An impression is taken of the eye socket from which is prepared a positive mold on which the synthetic eye is cast. A variety of prosthesis and techniques are used to provide movement of the artificial eye in concert with the person's good eye. These include an enucleation implant or an anophthalmic insert. More recently, orbital implants that are sufficiently porous that the patient's blood vessels and tissues grow into the implant allowing a surgical procedure to give artificial eye movement. A post or peg interconnection is provided between artificial eyes and orbital implants so that the eye moves with the orbital implant which follows the good eye.
Hollow prosthetic eyes have been offered since the 1960's and are more recently described in the article THE MAKING OF A HOLLOW PROSTHETIC EYE by Eric A. Jarling, JOURNAL OF AMERICAN SOCIETY OF OCULARIST, circa 1986. This hollow prosthesis is only offered for those patients whose anophthalmic cavity is larger and deeper than normal, specifically those patients that were unable to be fitted with an orbital implant at the time of enucleation, or had experienced extrusion of an implant and were unable to have a second implant. For those patients, the ocular prosthesis would be quite large, and thus heavier. In this manufacturing procedure, two halves of the artificial eye are produced with a hollow interior and bonded together to form an integral prosthesis. The interior cavity of this prosthesis is sealed to avoid intrusion of fluids and bacteria.
Even with these advancements, it has been long well established that for many patients, the blinking and tearing mechanisms of the eye socket do not operate at all or are insufficient to allow the patient comfortable use. The problem of eye dryness is reviewed in an article, ARTIFICAL EYES AND TEAR MEASUREMENTS, by Lee Allen, at al a reprint in OPHTHALMOLOGY, February 1980, Vol. 87, No. 2 of a presentation at the Eighty-Fourth Annual Meeting of the American Academy of Ophthalmology in November of 1979, the article being incorporated herein by reference thereto. In addition, continuing problems of bacterial infections are suffered by some prosthetic users. These problems are not unlike those associated with wearers of contact lenses, except the problem is more severe. The increased prevalence of bacteria in the conjunctiva of anophthalmic sockets is reported in the article, THE ANOPHTHALMIC SOCKET AND THE PROSTHETIC EYE-A CLINICAL AND BACTERIOLOGIC STUDY, printed in the Anophthalmic Plastic and Reconstructive Surgery Vol. 5, No. 4, pp 277-280, 1989, also incorporated herein by reference. In this study, the patients were instructed to handle their prosthesis as infrequently as possible, but about twenty-five percent admitted to removing their prosthesis at least once each week. The study concluded that this "frequent manipulation" increased the incidence of bacterial flora.
A number of techniques have been directed to the problem of dry artificial eyes including the use of BioCoat OPT supplied by Bio-Metric Systems, Inc. of Eden Prairie, Minn. This coating is a chemically bonded hydrophilic polymer that is applied to the artificial eye. Periodic retreatment of the coating is required. A solid methyl cellulose lubricant, marketed under the trademark LACRISERT®, by Merk, Sharp and Dohme of West Point, Penn., has been developed and approved for severe natural dry eye problems by the U.S. Food and Drug Administration. This product is a small solid cylindrical body of lubricant that is inserted under the lower eyelid and allowed to slowly dissipate during the day providing a thickened film and lubrication for the natural eye. This product was also tested for use with artificial eye wearers with limited success. Unfortunately, the liquification of the LACRISERT® insert requires more liquid than is produced in the anophthalmic socket of many of the patients suffering from dry, unlubricated artificial eyes.
In U.S. Pat. No. 3,364,501 to Wilfred F. Stafford, et al, an inflatable orbital implant is provided with a passageway through the artificial eye to provide fluid irrigation offered to control the secretions which arise at the junction of the body tissue with the implant and create problems of infection and extrusion of the implant over varying periods of time. The Stafford procedure allows the insertion of a small tube to force an irrigating liquid through the passageway to the rear of the artificial eye and through a second passageway through the orbital implant.
Therefore, despite the continuing problem of dry eyes and bacterial growth, none of the devices, treatments or substitutes provide an answer to the problem and none of the devices or methods of the prior art attain the objects described hereinbelow.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a self-lubricating ocular prosthesis that will provide a continuous supply of lubricating and/or medicinal material to the artificial eye surface and the eye socket. The material may be a viscous liquid or a gelatinous form that is dispensed into the eye socket.
An important object of the present invention is to provide a continuous supply of lubrication allowing for longer intervals between removal of the artificial eye for cleaning of surface deposits on the prosthesis.
It is a further object of the present invention to provide a prosthetic eye that includes a chamber for a supply of material which is dispensed to the eye socket upon demand or by natural movements.
It is an additional object of the present invention to provide a prosthetic eye that provides a continuous supply of liquid which is sufficient to liquify the LACRISERT® lubricant whether it is inserted under the eyelid or in a receptacle in the prosthetic eye.
It is a specific object of the present invention to provide a prosthetic eye that has a reservoir of lubricating or medicinal material with a mechanism that allows the natural eye movement to discharge liquid from the eye.
It is an additional specific object of the present invention to provide a prosthetic eye with a reservoir connected to a push button on the eye surface to dispense liquid or gel as needed by the wearer.
A particular object of the present invention is to provide a prosthetic eye that can provide a continuous discharge or a discharge upon demand of a suitable bactericide or bacterial retarder to essentially eliminate the problem of bacterial infections in ocular prosthesis wearers.
It is a further object of the present invention to provide an artificial eye with a more "wet" looking anterior surface for cosmetic purposes.
It is a particular object of the present invention to provide a self-lubricating artificial eye with a chamber that is easily cleaned by the wearer.
It is an additional object of the invention to provide a self-lubricating prosthesis that is light in weight and exerts less pressure on the lower eyelid of the wearer.
It is an object of the present invention to provide a self-lubricating artificial eye prosthesis that includes a chamber that can be filled with lubricant or medicine with an applicator without removal of the prosthesis.
It is a further object of the present invention to provide a self-lubricating ocular prosthesis with at least one chamber for storing lubricant that can be viewed by the wearer to determine how much of the lubricant has been used.
An aspect of the invention is a self-lubricating ocular prosthesis for use in a person's orbital cavity. The prosthesis includes a solid rigid prosthetic eye body that includes an anterior convex surface through which an iris-cornea-scelera simulation is visible and a posterior surface, proximately conforming to a surface of the person's orbital cavity. The prosthesis further includes a first chamber in the body defining a reservoir volume and an access passage from the first chamber through the posterior surface of the body. The prosthesis also includes a cap releasably closing the access passage and the cap includes an outside face proximately conforming to the posterior surface of the body, and a composition of polymeric material chosen from the group consisting of semi-rigid and flexible polymeric resins. The prosthesis further includes a bore opening from the first chamber through a surface of the body.
It is preferred that the bore opening from the first chamber be through the anterior surface of the body. It is further preferred that the bore opening be a round hole of a diameter in the range of about one-half to about two millimeters. It is also preferred that the access passage and the cap include a plurality of annular detents holding the cap in place closing the access passage. It is further preferred that the ocular prosthesis further includes a vent hole opening from the first chamber to a surface of the prosthetic eye. It is also preferred that the vent hole open from the first chamber to the posterior surface. It is more preferred that the vent hole open through the cap to the posterior surface. It is also preferred that the ocular prosthesis further include dispensing means in the prosthetic eye to discharge material from the first chamber to the orbital cavity. It is further preferred that the dispensing means includes a circular opening from the first chamber to the anterior surface, a sphere of a diameter larger than the circular opening but small enough that a portion of the sphere can extend out through the circular opening while allowing the sphere to freely rotate and allow material in the first chamber to flow out of the circular opening. It is also preferred that the dispensing means include an aperture through the anterior surface of the body in communication with the first chamber and a membrane member proximate the anterior surface closing the aperture. It is further preferred that the dispensing means include an aperture from the first chamber to the anterior surface, a button of a shape less that the shape of the aperture but small enough that a portion of the button can extend out through the aperture, and means to bias the button against the circular opening while allowing the button to be pushed into the first chamber to urge material in the first chamber to flow out of the bore opening. It is also preferred that the cap be of a composition chosen from the group consisting of silicone rubber and light cured acrylic resin. It is further preferred that the ocular prosthesis further include a second chamber and a second bore opening from the second chamber to the anterior surface. It is also preferred that the second bore opening be positioned immediately below the first bore opening. It is further preferred that the second bore opening to the second chamber abut and communicate directly with the first bore opening. It is also preferred that the second chamber open to the first chamber.
Another aspect of the invention is a method of using a self-lubricating ocular prosthesis in a person's orbital cavity. The method includes providing an ocular prosthesis as described above and inserting the prosthetic eye body into the person's orbital cavity. The method continues by injecting a material chosen from the group consisting of a liquid and a gel into the chamber through the bore opening, and applying finger pressure to the anterior surface of the body to eject material from the bore opening as needed. Another aspect of the invention is another method of using a self-lubricating ocular prosthesis in a person's orbital cavity, the method includes providing an ocular prosthesis as described above that includes a dispensing means in the prosthetic eye to discharge material from the first chamber to the orbital cavity. After inserting the prosthetic eye body into the person's orbital cavity and injecting a material chosen from the group consisting of a liquid and a gel into the chamber through the bore opening, the method continues by actuating the dispensing means to eject material from the chamber into the orbital cavity. It is preferred that the material be a viscous or gelatinous eye lubricant, and more preferred that the fluid include a medicine.
Yet another aspect of the invention is a method of producing a self-lubricating ocular prosthesis for use in a person's orbital socket. The method includes preparing a positive mold with a surface proximating the person's eye socket and casting a solid prosthetic eye body which includes an anterior convex surface through which an iris-cornea sclera simulation is visible, and a posterior surface conforming to the surface of the positive mold. The method continues by excavating a first chamber in the body defining a reservoir volume through an access passage through the posterior surface of the body. The method then continues by filling the first chamber with filler means to temporarily fill the void and be easily removable and applying a release agent to surface of the access passage, the posterior surface, and the surface of the positive mold. The method then continues by filling the access passage with polymeric material chosen from the group consisting of uncured semi-rigid and flexible polymeric resins and partially cured semi-rigid and flexible polymeric resins. The method then continues by pressing the posterior surface against the surface of the positive mold and curing the polymeric material to form a cap releasably closing the access passage with an outside face proximately conforming to the posterior surface of the body. The method then continues by removing the cap and removing the filler means, and finally drilling a bore opening through the surface of the body into the first chamber. It is preferred that the method further include providing a lip between the access passage and the chamber and carving a plurality of spaces in the filler means below the lip before filling the access passage with the polymeric material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a device of the present invention on an orbital implant in a patient's eye socket.
FIG. 2 is a side perspective view of the device illustrated in FIG. 1 removed from the eye socket.
FIG. 3 is a top frontal perspective view of the device.
FIG. 4 is a rear view of the device.
FIG. 5 is a cross-sectional view taken along lines 5--5 of FIG. 4.
FIG. 5a is a partial cross-sectional view of a second embodiment of the invention.
FIG. 5b is a partial cross-sectional view of a third embodiment of the invention.
FIG. 5c is a partial cross-sectional view of a fourth embodiment of the invention.
FIG. 5d is a partial cut away front view of the device illustrated in FIG. 5c.
FIG. 6 is a partial cross-sectional view of the device illustrated in FIG. 5, showing removal of the cap.
FIG. 6a is a second view of FIG. 6 illustrated another way of removal of the cap.
FIG. 6b is an enlarged view of a portion of FIG. 6a.
FIG. 7 is a rear perspective view of the device of FIGS. 1 through 5 with the cap removed to show the internal cavity.
FIG. 8 is a perspective view of the device illustrated in FIG. 1 with a lubricant being added to fill the chamber while the eye is in place.
FIG. 9 is an elevational view of a prior art prosthetic artificial eye resting on a stone mold reproducing the posterior shape of the artificial eye.
FIG. 10 illustrates a cross-sectional view of said artificial eye removed from the mold.
FIG. 11 illustrates a partial cross-sectional view of the eye inverted to grind out a chamber opening to the posterior side.
FIG. 12 is a cross-sectional view of the same eye showing the packing of the cavity with plasticine or wax leaving a depth for the cap and an application of the resin for the cap.
FIG. 13 is a cross-sectional view wherein liquid resin has been added on top of the plasticine or wax and the posterior surface of the artificial eye is pressed against the mold.
FIG. 14 is a frontal view of a fifth embodiment of the invention.
FIG. 15 is a cross-sectional view taken along lines 15--15 of FIG. 14.
FIG. 16 is a rear view of the device of FIG. 14.
FIG. 17 is a frontal perspective view of a sixth embodiment of the invention.
FIG. 18 is a rear view of the device of FIG. 17.
FIG. 19 is a cut-away cross-sectional view taken along lines 19--19 of FIG. 18.
DESCRIPTION OF PREFERRED EMBODIMENTS
Ocular prosthesis 20 in the form of an artificial eye is illustrated in FIG. 1 in place on orbital implant 22 under upper eyelid 24 and lower eyelid 26. In FIG. 2, device 20 has been removed exposing anterior surface 28 through which sclera simulation 30, iris simulation 32 and cornea simulation 34 is visible. The front perspective view of FIG. 3 shows one thirty-second inch round bore opening 36 and one thirty-second inch round vent opening 38 opening through anterior surface 28 above iris simulation 32 barely visible through sclera simulation 30. In these locations both openings are under upper eyelid 24 when in use. In FIG. 4, the rear perspective view shows posterior surface 40 and cap 42. In FIG. 5, transparent center cast section 44 covers and provides the visual appearance to display iris simulation 32 and cornea simulation 34 on the main body of the acrylic casting body 45. As also shown in FIG. 6 cavity 46 opens through access 47 to posterior surface 40 and through openings 36 and 38 through anterior surface 28. Cap 42 releasably closes cavity 46 and conforms to posterior surface shape 40. Alternative embodiments are illustrated in FIGS. 5 a, 5b, and 5c. Artificial eye 48 is cast of body resin 50 with clear acrylic resin section 52 essentially covering the entire anterior surface and making cavity 54 visible when the wearer lifts upper eyelid 24 to check the contents of the cavity. Bore opening 56 opens to the anterior surface and vent hole 60 opens directly through cap 58 to the posterior surface. In FIG. 5b, ocular prosthesis 62 includes cavity 63 closed by cap 42'. The "prime" and "double prime" designations throughout the specification indicate that that element is essentially identical to that of an earlier figure. Bore opening 64 and vent opening 65 open from cavity 63 through anterior surface 28'. Cavity 68 is drilled into solid body to receive LACRISERT® insert 70 into that cavity opening directly through anterior surface 28'. Cavity 68 is positioned directly below bore opening 64 so that lubricant flowing downwardly provides sufficient lubrication for the LACRISERT®. In FIG. 5c, device 72 includes bore openings 76 and LACRISERT® bore opening 80 drilled side by side and joined together opening from the cavity through anterior surface 28". Vent hole 78 provides the standard air vent to facilitate flow. In this embodiment, the LACRISERT® 82 swells and lubricate through direct contact with lubrication fluid 88 inside cavity 74. As shown in FIGS. 6, 6b, and 7 at least one detent projection 84 extends under lip edge 86 of the eye body around opening to cavity 46. Most views show detents, such as detents 84, at each cross-section edge of the cap. However, this is due to choice of the cross-section cut and a plurality of detents are sufficient, preferably about four for each cap, spaced around the periphery. As illustrated in FIG. 6, pin 89 can be used to remove cap 42 either by inserting it through bore opening 36 or vent opening 38 or as shown in FIGS. 6a and 6b by prying under tab 85 of the cap to lift it off. Tab 85 aids in positioning cap 42 over the access opening. In FIG. 7, cap 42 has been removed exposing cavity 46 bounded by lip edge 86. As shown here, bore opening 36 and vent opening 38 open directly from cavity 46 through anterior surface 28. In FIG. 8, standard one half ounce lubricant bottle 90 containing a standard lubricant solution approximating normal tears is equipped with bent polyethylene tube extension 92 which is inserted into hole 36 to fill cavity 46 with the liquid. Since hole 36 is under upper eyelid 24, it is necessary to lift the eyelid to insert tube 92 into the hole and fill the cavity. Through capillary action, the contact with the eyelid draws fluid from the cavity to wet the eye ball.
FIGS. 9 through 13 illustrate a method of manufacture of a device of the present invention. Artificial eye 94 is made using standard methods well known in the art that has been impression fitted to the patient. Clear section 98 is cast in the eye to provide the iris and cornea simulations. Using a prosthesis mix quick set stone or plaster, platform 96 is made for pressing and fabrication of the chamber cap. The stone platform is trimmed and artificial eye 94 is removed as shown in FIG. 10. In FIG. 11, the artificial eye is inverted so that the posterior surface is facing upwardly. Using rotary ball grinder 100, cavity 102 is routed out of the eye from the rear. In FIG. 12 plasticine, wax, clay, or Silly Putty® are used as filler plug 106 in the cavity to form the space that will remain open. A plurality of detents 104, similar to detents 84 above, are formed by forming a plurality of small hollows under the lip after which medical grade R.T.V. silicone, such as Dow Corning R.T.V. No. 382 silicone is spread over the plug. Platform 96 is re-engaged and pressed for about one minute against the posterior surface of eye 94 forming silicone resin cap 108 to the exact shape of platform 96. When the silicone rubber has fully cured, platform 96 is removed, the cap is pried off and the putty removed. Holes are drilled into the cavity at the chosen points. Twist drills, size sixty through eighty are used to drill the holes into the body, that is the bore openings and vent openings into the chambers. For certain embodiments, the cap may be shaped to hold a ball or button in place by merely indenting the putty to the chosen shape and allowing the silicone rubber to flow into the cavity and upon curing to form the means to hold the ball or button in place. The chamber may be positioned at any location in the artificial eye, but it is preferred that the chamber be positioned at the top upper most section so that the bore opening can be under the upper eyelid. The liquid flows outwardly under the lid and over the prosthesis and down to reach the lower portions of the eye. The chamber is ground with a small ball burr with an undercut leaving a rim around the circumference of the chamber rim to provide a surface for detents extending from the cap to hold the cap in place. The interior of the chamber is polished. The R.T.V. silicone is catalyzed for gelling in about twenty seconds. The chamber is overfilled and immediately the posterior surface of the artificial eye is pressed against the stone platform mold covered with a thin film of Vaseline®. Hard hand pressure is applied for at least one minute to force the silicone into and around the chamber hole. The silicone sets sufficiently in ten minutes or less after which the silicone is lightly polished in the area of the chamber. The silicone is removed from the chamber and trimmed with scissors or a razor blade. The bore opening used to allow the lubricant to weep from the chamber is drilled with a drill or a fine burr and finely polished. Lubricant is placed in the chamber, the cap is placed in position closing the chamber. A notch tab in the chamber access aids in placement of the cap. After the prosthesis has been cleaned and any excess lubricant removed, the prosthesis is inserted into the eye socket and attached to the orbital implant. An alternative cap composition is TRIAD II light cured acrylic resin supplied by Dentsply of York, Pennsylvania. This semi-rigid material is used in the same fashion as the silicone rubber except that it is covered by a transparent film and cured by exposure to the light after which it is trimmed and ground to the proper shape and surface smoothness.
While devices with only one large chamber and a small chamber are illustrated, it will be clear that a plurality of chambers of the same or different sizes may be provided in the artificial eye. These chambers may be charged with the same lubricant or may be charged with different materials. Thus one chamber can be filled with a lubricant, while the other can be charged with a medicine, such as a bactericide, antihistamine or the like.
Certain devices and mechanisms in the artificial eye are described hereinbelow to aid in dispensing the lubricant from the artificial eye. The simplest method is merely to have the patient press on the prosthesis thus exerting pressure on the cap against the orbital implant. This tends to dispense a small amount of lubricant from the chamber through the weep hole and effectively lubricate the eye. The flexible or semi-rigid character of the cap material allows the cap to flex when pressure is applied to dispense liquid from the chambers.
In FIG. 14, device 110 utilizes ball applicator 112 which rotates freely while protruding through anterior surface 114. As shown in FIG. 15, chamber 118 is carved out of body 116. Ball 120 is slightly larger than the diameter of the hole extending through anterior surface 114 from the chamber. Cap 122 is formed of silicone rubber with extension 124 extending into the space of chamber 118 and holding ball 120 against the hole while allowing it to rotate as it contacts the upper eyelid. Another applicator device is illustrated in FIGS. 17 through 19 wherein device 126 include button 128 flush with the anterior surface proximate weep hole 130 and vent hole 132, all the openings extending into chamber 140. Button 128 is molded of the TRIAD II light cured acrylic resin and is shaped to extend out through opening 134 but of a size too large to come out of the hole. Cap 136 is formed with extension 138 to abut the rear surface of button 128 and hold it in position. When button 128 is depressed with the person's finger, lubricant is expelled through weep hole 130.
While this invention has been described with reference to the specific embodiments disclosed herein, it is not confined to the details set forth and the patent is intended to include modifications and changes which may come within and extend from the following claims. | 4y
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STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates to the reading and writing of data in a processing system. More particularly the invention provides a low overhead update notification mechanism for concurrent processes accessing data bases.
(2) Description of the Prior Art
A known prior art means utilizes an interrupt method in which submarine combat system processes notify each other of their updates to shared resources by using soft interrupts (versus hardware interrupts). These soft interrupts provide inter process update notification. The typical computing system has the interrupting processes (via kernel services) either set conditional flags or queue the conditions, and either asynchronously or synchronously has the interruptible processes (via the operating system) either check the flag or the queue for any interrupting conditions. When a condition exists the operating system invokes interrupt handlers. The interrupt handlers are procedures provided by the executing programs for activation on interrupts. More specifically, processes generate interrupts for other processes by calling the operating system at least once per interrupt. Each call initiates the operating system accesses and updates interrupt natured data structures in the target process. The operating system then allows the interrupts when an interrupt returns true and the process is either in the execution state or in the ready state. The operating system handles the interrupt by placing a handler frame (a call) on the stack. The state of the art, from interrupt generation to handler invocation, requires processing overhead and incurs response latencies. The delays are due to activities that must run to completion before interrupt conditions are acknowledged, which in turn are due to switching to and from the operating system and processes.
Another prior art means utilizes a synchronization method. In this method submarine combat system processes notify each other of their updates to shared resources by invoking synchronization primitives. These primitives are often termed "P" and "V", or "Signal" and "Wait", or "Lock" and "Unlock." When P and V, and Signal and Wait primitives are used, they are implemented as operating system services that require the process surrender the computer system to the operating system. The client does a P/Wait when it needs the update notification and the writer does a V/Signal when it generates the update notification. Each time a process invokes either a P or a V, it will call the operating system at least once per that invocation. This switching to and from the operating system causes P and V primitives to introduce substantial overhead. In addition, P invocations indiscriminately cause writer(s) and reader(s) to wait serially for the resource. The P primitive may also affect the behavior of a priority based real-time system. On some operating systems, P invocations have a tendency of creating a priority inversion when separate priority queues are not maintained for waiting processes. The absence of priority queues treats all processes as equal activities.
P and V primitives are often based on Lock and Unlock operators. Lock and Unlock operators are often directly based on some computer hardware mechanism. In practice, a successful lock allows a process to access the resource; an unsuccessful lock requires the process to re-invoke the lock operator. Many computer systems make Lock and Unlock operators directly available to processes, i.e., they don't require P and V calls, and operating system intervention. Processing of unsuccessful locks is accomplished by having the process either re-invoke the lock until success, or by having it block and continue at some later time, or by having it perform a default action. The reinvoking of the lock is often called a spin-lock and involves busy waiting and hence wastes precious computer system processor cycles. The blocking process as a strategy usually creates the same effect as the P operation, i.e., it serializes access. Unlike the P primitive, the lock operator doesn't have to result in suspended processing, but often default actions are not available when data must be accessed and processed.
Submarine combat systems can conceptually be characterized as a processing pipeline with the flow being occasionally broken by human operator actions. Two generic processing structures in submarine combat systems are manifest when this conceptual model is applied. The progression from data to information usually has many processes feeding many other processes as multiple processing stages. The data bases shared to pipe data from one stage to another stage usually have one writer to each data base, or some set of records in it, and several readers accessing the data bases. This processing structure represents the first category, and the focus of the invention. The second category is another processing structure where the computer system of a submarine combat system operates on data for, presents information to, and assists the actions of its human operators. Many of these actions often result in a break in the combat system processing pipeline. Often access to data bases is necessary, processes acting on the human operator's behalf may require sole access to either select data bases or sets of data base records. This often requires synchronization with writers in some stage of the processing pipeline. This latter processing scenario requires either the P/V or the Lock/Unlock solutions.
SUMMARY OF THE INVENTION
Accordingly, it is a general purpose and object of the present invention to provide an improved access of a data base that is subject to being updated at any time. It is a further object that the read portion of the system is aware of this updating if it is reading the data base when the updating occurs. Another object is that the system be able to tell the nature of an updating that occurred. Further objects are that the system be inexpensive, and easy to operate and understand.
These objects are accomplished with the present invention by providing a computer system in which a data base can be updated at any time. Several counters are used to accomplish this. Through comparison of the value of the counters the reading portion of the system is inhibited from commencing to read the data base during an update. In addition, the value of the counters informs the read portion of an update to the data base when the read subroutine has commenced prior to the update and the update subroutine has commenced prior to the completion of the read step. The reading portion of the system is also capable of determining what type of prior updating occurred,
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A and 1B are diagrammatic representations of a first prior art means for the processing of operations among the system components;
FIG. 2A and 2B are such representations of a second prior art means for the processing of operations among the system components;
FIG. 3A and 3B are such representations of a third prior art means for the processing of operations among the system components;
FIG. 4A and 4B are diagrammatic representations of the present inventive means for the processing of operations among the system components;
FIG. 5 is a block diagram of an update notification system in accordance with the present invention as represented in FIGS. 4A and 4B;
FIG. 6 is a flow diagram of the updating of the data base in the update notification system of FIG. 5; and
FIG. 7 is a flow diagram of the reading of the data base in the update notification system of FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Computer systems used to prototype and implement various systems must support and execute multiple concurrent processes (programs in execution) in their hardware and software. These computer processes monitor, model, simulate and control world processes and objects.
Each pair of FIGS. 1A and 1B, 2A and 2B, 3A and 3B represent a prior art system. FIGS. 4A and 4B represent the present invention. The way to interpret these figures is to use two simple rules. Arrows pointing in either the horizontal or the vertical direction represent inexpensive processing of operations among the system components (the operating system (OS) 11, the central processing unit (CPU) 13, the random access memory (RAM) 14, and application programs (AP#)10, 10a, 10b, 10c, 12, 12a, 12b, and 12c). In the foregoing, the term "inexpensive processing" generally refers to conservation of computer system processing cycles. The OS 11, CPU 13, and RAM 14 may or may not be the same in each of the figures depending upon the designers selection of components. The AP#10, 10a, 10b, , 10c, 12, 12a, 12b, and 12c also may differ from each other. Arrows pointing in the diagonal direction represent expensive processing necessary to carry update notification operations. Diagonal processing requires hundreds of microseconds, while horizontal and vertical processing require a fraction of a micro second. The operating system 11 and application programs 10, 10a, 10b, 10c, 12, 12a, 12b, and 12c can easily exercise the CPU 13 and RAM 14 hardware components. In comparison, it requires many operations for the operating system 11 and application programs 10, 10a, 10b, 10c, 12, 12a, 12b, and 12c to exercise each other. It usually requires that the state/context of programs be saved and that many control modules be invoked in the operating system. In the illustrations the CPU 13 and RAM 14 boxes touch each other, these components are closely linked and are often inseparable, e.g., all CPU 13 instructions come from memory 14 and usually operate on memory 14. The operating system 11 and the application programs 10, 10a, 10b, 10c, 12, 12a, 12b, and 12c exercise the CPU 13 and the RAM 14 constantly, the horizontal and the vertical arrows indicate the components focused on by the operations, versus the details of the operations. The arrows signify the degree or criticality of that system component in accomplishing update notifications. Note that the illustrations implicitly demonstrate an approach for update notification not explored by the prior art techniques. In the prior art notification occurred in the diagonal and the horizontal but never in the vertical as occurs in the present invention.
FIGS. 1A and 1B show that AP1 10a notifies AP2 12avia OS 11 by using the signal and wait synchronization primitives. FIGS. 2A and 2B show that AP1 10b notifies AP2 12b Via OS 11 by sending an interrupt that is handled by AP2's handler. FIGS. 3A and 3B show that AP1 10c notifies AP2 12c via a CPU 13 atomic lock operator (a.k.a. test and set instruction). The above three examples refer to prior art systems.
FIGS. 4A and 4B show the present invention in which AP1 10 notifies AP2 12 via RAM 14 based counters/registers (a.k.a. variables).
Referring now to FIG. 5 there is shown in the present invention the application program (AP1) 10 and the application program (AP2) 12 connected to RAM 14. The RAM 14 comprises a data base record 14a, a first counter 14b designated update-counter, a second counter 14c designated new-or-removed-flag and a plurality of registers 14d. The writer AP1 10 modifies the data base record 14a, and increments each of the counters 14b and 14c. The reader AP2 12 reads data base 14a and performs operations, to be explained later, on counters 14b and 14c and the plurality of registers 14d.
FIG. 6 is a flow diagram for the operation of the writer 10. FIG. 7 is a flow diagram for the operation of the reader 12. While only one reader 12 is shown in the drawings, it is to be understood multiple readers 12 with associated identical flow diagrams could be used. In addition, multiple data base records 14a could be used.
The invention is the application of sets of two counters 14b and 14c for the update notification to multiple computer system processes accessing at least one shared data base record 14a in: (i) submarine combat systems, (ii) other military real time tactical command and control systems, (iii)semi-automated urban rapid transit train dispatch and schedule modification systems, (iv) real time semiautomatic industrial process, power plant, or power distribution control systems, and (v) the like. The application of two counters 14b and 14c per data base record 14a, allows combinations of writer 10 and reader(s) 12 to share data base record(s) 14a. The registers 14d used in conjunction with the update-counter 14b are the update-counter register designated register (U), the register having the value of register (U) prior to the present access transaction is designated old (U).
The registers 14d used in conjunction with the new-or-removed-flag 14c are the new-or-removed-flag register designated register (N), the register having the value of register (N) prior to the present access transaction is designated old (N).
The FIG. 6 logic for the writer 10 is as follows:
Step 1: the writer 10 increments by one the update-counter 14b.
Step 2: the writer 10 provides the following elementary subroutines:
when adding a record it increments by one the new-or-removed flag 14c, and updates the data base record 14a.
when revising the record it does not increment the new-or-removed-flag 14c, and updates the data base record 14a.
when deleting a record it increments by one the new-or-removed-flag 14c.
However in the present use of the invention the storage for the record is never deleted and is reallocated to a future add.
Step 3: the writer increments by one the update-counter 14b.
It is to be noted from the above that when the writer 10 is updating the data base record 14a, the update-counter 14b has been updated by an increment of one. Following the updating by the writer 10 the update-counter 14b has been incremented by a total of two, and when adding or deleting a record the new-or-remove-flag 14c has been incremented by one, but the new-or-remove-flag 14c has not been incremented when the record has been revised.
The FIG. 7 logic for the reader 12 is as follows:
Step 1
set register (U) equal to the update-counter 14b;
check if the register (U) is not equal to the old (U), if not equal than proceed to step 2, else the return value is unchanged record, and proceed to step 6.
In order to proceed from step 1 to step 2 the writer 10 must have incremented the update-counter 14b. Otherwise go to step 6.
Step 2
check if register (U) modulus 2 is equal to zero, if zero then proceed to step 3, else the return value is collided on access to record, and proceed to step 6.
In order to proceed from step 2 to step 3 the writer 10 must have incremented the update-counter 14b an even number of times. This shows the updating was completed. A value of one indicates the writer is updating the data base record 14a. In this case the system proceeds to step 6.
Step 3
access the data base record 14a; and
set register (N) equal to new-or-removed-flag 14c and proceed to step 4.
Step 4
check if register (U) is not equal to update-counter 14b, whereupon if not equal the return value is collided on record and proceed to step 6, or else proceed to step 5.
If the register (U) is equal to the update-counter 14b then the access was successful. If they are not equal then the writer 10 was modifying the data base record 12a during access. Step 4 always guarantees the determination of the writer 10 during step 3. It is necessary that the computer memory hierarchy maintain the true value of counters 14b and 14c throughout the hierarchy.
Step 5
check if register (N) is equal to old (N), if equal then the return value is "revised record," else check if register N modulus 2 is zero, if zero then the return value is "deleted record," else the return value is "added record;" set old (U) equal to register (U); set old (N) equal to register (N); and proceed to step 6.
Step 6
before returning to step 1, either defer processing to some other time or take other/default action.
There has therefore been described a means of providing update notification between a writer 10 and one or more readers 12. An advantage is that the writer 10 is never inhibited from updating the data base record 14a, i.e., the writer 10 never has to queue for the data base record 14a. The reader 12 can access the data base record 14a at will, deferring processing or taking alternate actions during collisions. The writer 10 indicates to the readers 12 Whether the record is unchanged, collided, added, updated or deleted. Except for collisions operating system intervention is never required. The absence of intervention reduces overhead substantially. Collisions can be processed by requesting the operating system to queue the process for the processor at priority, thus eliminating the possible priority inversion caused by the P primitive.
It will be understood that various changes in the details, materials, steps and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. | 4y
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CROSS-REFERENCE TO RELATED APPLICATION
The present application is a division of my copending application Ser. No. 693,273, filed Jan. 22, 1985 now U.S. Pat. No. 4,603,432 granted July 29, 1986.
BACKGROUND OF THE INVENTION
The present invention relates generally to a method and for containing spills of liquid material, and, more particularly, to a method for spill containment using a collapsible bag.
The highway transportation of hazardous and non-hazardous liquid chemical and petroleum products is a thriving industry in this and other countries with literally billions of gallons of such products being transported annually. Tanker trucks having liquid transporting systems are normally utilized to effect the transport of these materials and will sometimes develop leaks in their valves or tanks, thereby permitting the liquid material contained therein to escape to the outside environment in the form of a liquid spill.
Numerous statutes have been enacted which provide for monetary fines against operators of tanker trucks if a defect in the liquid transporting system is found and/or a liquid spill occurs. The operators may also be required to absorb the cost of the cleanup of the liquid spill. Heretofore, the transportation industry has not had a simple readily available means to contain these leakage problems to minimize their environmental impact.
Hazardous and non-hazardous liquid materials are also transported and stored in large cylindrical barrels or drums which have a tendency to leak as a result of improper manufacturing techniques, improper or abusive handling thereof or chemical reactions within the materials stored. It has been the practice of the industry to place a barrel with a leakage problem in an oversized barrel or drum commonly called an "overpack", thereby contaning the leaking material. However, these "overpacks" are quite expensive to purchase, very difficult to store and extremely cumbersome to handle. Therefore, it would be desirable to provide a system to handle these leaking barrels which would alleviate the inconveniences presented by the "overpack" drums.
It is an object of the present invention to provide a novel method for spill containment using a collapsible bag which is readily usable to contain a spill of liquid material.
It is also an object to provide such a method of spill containment which may be effected quickly to minimize the environmental impact of a liquid spill.
Another object is to provide such a method which can be readily practiced without special equipment.
SUMMARY OF THE INVENTION
It has now been found that the foregoing and related objects may be readily obtained by a method using an emergency spill containment bag for receiving and containing liquid materials. This leak-proof flexible bag member a fluid impervious material having a main body portion defining an enclosure with bottom and side walls. The body portion has an opening at the top end thereof and a tubular extension portion a fluid impervious material is bonded at its inner end to the top end, and is open at its other end and foldable into the main body portion. A multiplicity of pairs of engagement means is provided on the main body portion adjacent the upper end thereof for mounting the bag on a support structure. A multiplicity of pairs of engagement means is also provided on the extension portion adjacent the other end thereof for mounting said bag on a support structure.
Preferably, the engagement means includes portions of loop-like configuration. The plurality of loop means on the main body portion is preferably two pairs of loop means attached to the sidewall on opposite sides of the opening.
The main body portion is desirably formed from a first length of material providing the bottom wall and two opposed sidewalls extending from the periphery of said bottom wall. Two additional lengths of material provide two opposed sidewalls and are secured along their lower and side margins to the first length to form the enclosure. Strap means is provided as a part of the bag and is adapted to engage selected ones of the plurality of engagement means, and closure means is provided adjacent the outer end of the extension portion to effect closure thereof. This closure means is conveniently a flexible cord element attached to the extension portion adapted to extend thereabout. Reinforcement means may be provided on the bottom wall.
In the method of containing a liquid spill from a tanker truck, the spill containment bag is suspended from a portion of the tanker truck having a leaking liquid containment vessel with the opening in said bag being disposed below and adjacent the point of the leak whereby the liquid material flows through the opening and into the enclosure. The containment bag is suspended by a plurality of loop means on the main body portion and strap means engaged with the loop means, and with the strap means being secured to the truck.
In containing a liquid spill from a liquid containing drum, the leaking drum is inserted through the opening and into the enclosure, and the liquid material escaping from the drum is contained within the enclosure. Closure means is used to close the opening in the containment bag about the drum. To insert the drum, it may be set in an upright position, after which the bag is placed thereover, and the drum and bag are inverted in tandem. Alternatively, the drum may be set in an upright position, the bag placed underneath the drum, and then the bag is pulled upwardly about the drum to enclose it.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a spill containment bag for use in the present invention shown in a fully extended condition;
FIG. 2 is a perspective view of the spill containment bag shown in a partially extended condition with the reinforced bottom portion being inserted therein and with portions broken away to illustrate internal structure;
FIG. 3 is a fragmentary perspective view of the spill containment bag showing the upper portion of the extension portion in a partially closed condition;
FIG. 4 is a perspective view of the spill containment bag shown in a collapsed or folded condition and an attachment strap used in conjunction therewith;
FIGS. 5-7 are perspective views of a tank truck with a liquid containment system showing various ways the spill containment bag can be attached thereto;
FIGS. 8-11 are diagrammatic views illustrating the sequence of steps used to insert a drum or barrel into the spill containment bag; and
FIGS. 12-15 are similar views illustrating another sequence of steps used to insert a drum or barrel into the spill containment bag.
DETAILED DESCRIPTION OF THE INVENTION
Turning first in detail to FIG. 1, therein illustrated a spill containment bag for use in the present invention and generally designated by the numeral 10. The containment bag 10 has a generally rectangular configuration and includes a main body portion 12 with an extension portion 14 having an upper opening 16 for accessing the interior of the containment bag 10. The main body portion 12 and the extension portion 14 have lifting or support harnesses thereon and respectively designated by the numerals 18 and 20 for purposes to be hereinafter described.
The main body portion 12 is manufactured from three pieces of sheet material with welded or heat bonded seams to provide a leak-proof container. The sheet material is preferably a foldable, durable synthetic rubber such as natural rubber (e.g. butadiene/acrylonitrile copolymer, polychloroprene, polyisoprene) polyethelene, polypropylene, and polyvinyl chloride, capable of withstanding highly concentrated acids, solvents, petrochemicals and other liquid chemical compounds of either hazardous or non-hazardous nature. The resin sheeting may be reinforced with cotton, rayon, nylon and other fibers, and may comprise a laminate of a woven material with a resin face providing the fluid impermeable structure. The pieces of sheet material of the main body 12 are initially cut to size to provide a central portion 15 and two side portions 17. The central portion 15 forms the bottom wall 46 and two sides of the main body 12. The rectangular configuration of the main body 12 is completed by welding the side portions 17 to the central portion along seams 19. The areas of the intended seams 19 are cleaned and the overlapping portions are heated with a welding or heating tool to melt or bond the portions 15 and 17 together to create the seams 19.
Attached to the main body portion 12 adjacent the upper end thereof is the lifting harness 18 and the extension portion 14. The lifting harness 18 includes a strip or endless belt 22 of reinforcing material which overlies the sheet material of the main body 12, a plurality of engagement means in the form of loop elements 24, and an additional reinforcement strip or endless belt 26. The reinforcing material 22 may comprise an additional or thicker layer of the same foldable sheet material as that used for the main body portion 12, or a rugged woven fabric exhibiting the desired chemical resistance fabric which is attached or bonded to the outer portion of the main body 12 adjacent the upper edge thereof by plastic bonding or welding techniques, the loop elements 24 are preferably a polyester or nylon web material and are stitched to the main body portion 12 using high tensile strength polyester thread 28. The loop elements 24 are attached to opposed sides of the bag 10 for reasons to be hereinafter described. The additional strip or endless belt 26 of polyester or nylon web material is stitched to the upper end of the main body portion 12 and overlies the loop elements 24 and the reinforcing material 22 to provide added support therefor.
Extending upwardly from the main body portion 12 is the extension portion 14 which is welded or otherwise bonded thereto. A rectangular sheet of foldable sheet material similar to that used in the main body portion 12 is used to fabricate the extension portion 14 and it is welded with a vertically extending seam 29 along one corner thereof. Provided at the upper or terminal end of the extension portion 14 is the lifting harness 20 of a construction similar to the lifting harness 18 on the main body portion 12, and it includes a reinforcing strip or belt 30 welded or otherwise secured to the upper end of the extension portion 14, a plurality of loop elements 32 stitched thereon in a spaced apart relationship on opposed sides of the portion 14, and a second reinforcing strip or belt 34 overlying the reinforcing strip 30 and the loop elements 32. These components 30-34 of the harness 20 are manufactured from materials similar to the materials used for the harness 18. Additionally, the harness 20 is provided with a length of flexible cord or rope 36 secured to the reinforcing belt 30 below the reinforcing belt 34 with an overlying patch 38 stitched thereto. The inner circumference of the upper portion of the harness 20 has extending thereabout a self-adhering closure 40, such as provided by an ever tacky or activatable adhesive or a hook and loop material of the type sold under the trademark VELCRO, which may be engaged upon itself to provide a closure for the extension portion 14.
Turning now to FIG. 2, therein illustrated is the spill containment bag 10 in a partially extended condition with the extension portion 14 having been pushed or inserted into the interior of the main body portion 12 to lie flush against the sidewalls thereof and create an opening 42 therein. Also, a removable reinforcing member 44 preferably made from sheeting of similar to that utilized for the body portion 12, or a more rigid sheeting, or a woven fabric having the desired chemical resistance is shown inserted into the bag 10 to reinforce the bottom wall 46 of the main body portion 14. The reinforcing member 44 may be firmly secured to the inner or outer surface of the bottom wall 46 by utilizing welding or other bonding techniques.
As best seen in FIG. 3, the opening 16 of the extension portion 14 of bag 10 may be closed by folding the upper edge inwardly until the material of the self-adhering closure 40 comes into facing contact.
Turning now to FIG. 4, the bag 10 is depicted in a completely collapsed condition to permit easy storage in a truck or the like. Adjacent the bag 10 is an adjustable suspension or attachment strap 48 used to support the bag 10 in position to contain a spill of liquid material as will be hereinafter described. A pair of suspension straps 48 are provided with each bag and each would be adjustable by utilizing conventional length adjusting elements 47 to extend to a desired length, desirably a maximum of about twenty-two feet in length. Preferably, the straps 48 are made from a high strength nylon web material and have stainless steel safety hooks 49 disposed at the ends thereof.
Illustrated in FIGS. 5-15 are methods of using the containment bag to contain spills of a liquid material. Referring first to FIGS. 5-7, a tanker truck, generally indicated by the numeral 50, has a tractor 52 with a cab 54 used in combination with a tanker trailer portion 56 for highway hauling of liquid materials.
As seen in FIG. 5, the tractor 52 normally has a diesel or gasoline powered engine and at least one fuel tank 58. In this instance, the fuel tank is below the cab 54 and a leak has developed allowing fuel to escape. The operator has brought the vehicle to a halt and has suspended one of the spill containment bags 10 from the tractor 52 by draping a pair of the straps 48 over the fuel tank 58 and inserting the safety hooks 49 through the loop elements 24 on harness 18 of the bag 10. It should be noted that the bag 10 is in a partially extended condition with the extension portion 14 in the interior thereof and the straps 48 adjusted by use of the length adjustment elements 47 to partially enclose the tank 58. Any fuel leaking from the tank 58 will be collected or contained within the bag 10 and will not fall onto the pavement or surrounding area.
The trailer 56 has a liquid containing tank 60 mounted on the chassis 62 for holding, transporting or storing liquids. Located at the midpoint of the chassis to one side thereof are a series of valves 64 which permit liquid to be drawn from, or supplied to, the tank 60. In this instance, one of the valves 64 has developed a leak therein and the operator, by utilizing the loops 24 and the straps 48, has suspended the spill containment bag 10 below the valves 64 from a structural element 66 on the trailer 56. Thus he has contained the liquid spill in a manner similar to that described with respect to the fuel tank 58.
Referring to FIG. 6, the trailer 56 of the tanker truck 50 also has a valve 66 located at the rear portion 68 thereof. The bag 10 has been expanded to its fully extended condition which will permit the collection of a substantially larger volume of liquid material, and it has been suspended over the valve 66 by the loops 24 and straps 48 to collect the liquid from the leak in the valve 66.
Another technique for suspending the bag 10 from the trailer 56 is illustrated in FIG. 7. The straps 48 are extended around the tank 60 and the chassis 62 and thereby support the bag 10 under the belly of the trailer 54 to collect the liquid from the leak.
It is contemplated that multiple bags (not shown) can be placed alongside the first bag 10 suspended from the tanker truck, and the contents may be transferred from the initial containment bag by a pump or siphon (not shown) to the adjacent bags. This would permit a larger volume of liquid material to be collected without changing bags and afford the operator or an emergency response team more time to alleviate the leakage problem.
After the leak is stopped, the liquid collected in the containment bag 10 can be pumped into an emergency tanker truck or back into the tanker 50. Thereinafter, the bag 10 can be decontaminated for reuse.
Turning now to FIGS. 8-11, the bag 10 is constructed and designed for transporting and disposing of drums of material as an inexpensive and easily stored "overpack". The fifty-gallon drum or barrel 70 containing liquid material has a leak which is causing a spill 72. The user 74 simply draws the bag 10 over the upright drum 70 and then inverts the drum 70 and bag 10. Thereafter, the self-adhering closure 40 and the cord 36 are utilized to close the top portion of the containment bag 10 to enclose the drum 70 and collect the liquid 76.
Alternatively, as seen in FIGS. 12-15, the barrel 70 is set in an upright position (FIG. 12) and tilted onto one edge to allow the bag 10 to be placed thereunder (FIG. 13), and the bag 10 is then placed completely under the barrel 70 and raising or pulled in the direction indicated by arrows 78 to enclose the barrel as seen in FIG. 14. The self adhering closure 40 and the cord 36 can be used as previously described to enclose the drum 70 (FIG. 15).
The bags of the present invention may be carried in a folded condition within a compartment of a vehicle so as to be readily accessible in an emergency situation to contain a spill of any liquid. The bags may be carried in the vehicles of state, local and federal authorities, or stored in strategic locations such as tool booths, state garages and weighing stations to enable rapid response to emergency spills and minimize the environmental impact. The bag may also be used to contain spills from railroad tank cars and the like.
It should be apparent to those skilled in the art that the containment bag 10 can be formed in a variety of sizes and in a variety of ways. The fabric material may be fabricated from polyamide, polybutylene, polyethylene, polyester, and polypropylene, and mixtures and laminates thereof providing the desired chemical inertness and capability of withstanding highly concentrated acids, alkalis, solvents, petrochemicals and other hazardous and non-hazardous liquid materials. The bags may be reinforced internally or externally with glass, resin, carbon or other fibers to increase strength, and they may be coated with surfacing materials to enhance their chemical resistance so long as they retain the necessary flexibility to enclose the leaking vessel. The bags may be color-coded or otherwise labelled to indicate the types of liquid material that may safely be contained therein. Additionally, each bag may be labelled with an expiration date indicating the date on which the bag must be replaced because aging and exposure to fumes of materials being transplanted may be deterious to the fabric. Finally, gloves and other personnel protective equipment may be provided with the bag as an emergency kit.
Thus, it can be seen from the foregoing specification and attached drawings that the spill containment bag and method of the present invention provide an effective means for providing a collapsible and reusable container for containing spills of liquid materials. The method enables rapid development of an easily stored container to control a hazardous leak, and the bag may be readily and relatively economically fabricated. | 4y
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims the benefit of U.S. Provisional Application No. 60/773,504, filed on Feb. 14, 2006 and entitled “Wave Control Circuit for Plumbing Devices and Appliances,” which is incorporated herein by reference in its entirety.
BRIEF DESCRIPTION OF THE DRAWINGS
[0002] The features and inventive aspects of the present invention will become more apparent upon reading the following detailed description and drawings. In the drawing figures, which are merely illustrative, and wherein like reference numerals depict like elements throughout the several views:
[0003] FIG. 1 is an is an assembly view of a plumbing fixture and wave control circuit system formed in accordance with the teachings of this invention;
[0004] FIG. 2 shows a wave control circuit for the system shown in FIG. 1 ;
[0005] FIG. 3 is a flow diagram for the system shown in FIG. 1 ;
[0006] FIG. 4 illustrates an alternate logic flow diagram for the system shown in FIG. 1 ; and
[0007] FIG. 5 shows still another alternate logic flow diagram for the system shown in FIG. 1 .
DETAILED DESCRIPTION
[0008] The present invention relates to a wave control circuit used to control the operation of various plumbing devices and appliances. An illustrative embodiment of the invention is described herein, with reference to the accompanying drawing figures. A person having ordinary skill in the art will recognize that the invention may be practiced in a variety of orientations without departing from the spirit and scope of the invention.
[0009] FIG. 1 shows an illustrative embodiment of the invention used to control the operation of a plumbing device such as a faucet. The embodiment of the invention consists of a wave control circuit 10 , a plumbing device 20 and at least one sensor 30 . Alternatively, all or a portion of the plumbing device 20 may comprise the sensor 30 . As best seen in FIG. 2 , the wave control circuit 10 may include at least one sensor circuit 100 , at least one control circuit 110 , at least one driver circuit 120 , at least one valve 130 , and at least one sensor 30 associated with the plumbing device 20 . Control circuit 110 may comprise digital logic circuitry or a microprocessor 160 that executes software instructions built into the microprocessor 160 .
[0010] In either case, control circuit 110 reads output from sensor circuit 100 to control the flow of fluid through plumbing device 20 . Control circuit 110 sends an output signal through driver circuit 120 to control the flow of fluid through plumbing device 20 . Driver circuit 120 achieves the proper drive voltage and current necessary to enable or disable valve 130 . Valve 130 enables and disables functions of plumbing device 20 . For example, when valve 130 is open, fluid such as water may flow through plumbing device 20 , which is shown in FIG. 1 as a faucet.
[0011] Now referring to FIG. 2 , the wave control circuit 10 is shown to include a sensor circuit 100 , a control circuit 110 , and a driver circuit 120 . The wave control circuit 10 may be communicatively connected to the valves 130 . As best seen in FIG. 2 , the sensor circuit 100 may include a capacitive sensing network that is connected to proximity sensor 30 . The proximity sensor 30 may detect the presence of objects placed within the sensor's sensing field by capacitive charging and discharging. Therefore, when an object is placed within the sensing field of the proximity sensor 30 , the proximity sensor 30 is charged with a potential voltage and then discharged when the object is moved away. When the proximity sensor 30 is discharged, a small current or a voltage drop may be produced and the sensor circuit 100 may detect such a voltage drop. An example of proximity sensor used in such an application may be what is generally referred to as a charge transfer sensor. However, a person having ordinary skill in the art will understand that this is but only one example of the proximity sensor 30 that may be used in the application and other types of sensors may be used to perform the equivalent function.
[0012] Typically charge transfer sensors are used to detect objects in free space; thus, a very low capacitance field is generally present. However, the presence of running water may change the impedance of the capacitance network and, thus, may change and affect the sensitivity of sensor circuit 100 . To adjust for this possibility, the sensor circuit 100 is put through a recalibration procedure by either power cycling the sensor circuit 100 or engaging a recalibration function of the sensor circuit 100 to adjust to the load impedance presented to the circuit when the water flows. The recalibration accounts for the changed operating conditions and allows the sensor circuit 100 to have identical sensitivity when water is flowing or isn't flowing through the plumbing device 20 . A person having skill in the art will appreciate that a slight delay may be included before the recalibration. This delay may help to assure that impedance is accurately sensed or measured by the sensor circuit 100 .
[0013] The control circuit 110 may consist of discrete components such as a sequence of flip-flops, a clock, and logic gates to perform the functions described in FIGS. 3-5 . In an embodiment of the wave control circuit 10 , the control circuit 110 may further include a control logic circuit and a timer circuit. Upon a successful signal (i.e., detection of an object) from sensor 30 , sensor circuit 100 , which is connected to the control logic circuit, may output a high state. The high state of control logic circuit may trigger the timer circuit to create a timing event. Such timing event may enable the driver circuit 120 , which subsequently enables or disables valve 130 . The timing event may also be used to recalibrate the sensor circuit 100 while the sensor circuit 100 maintains its high output state. The high output state of the sensor circuit 100 may be maintained until a second signal from the sensor 30 is detected. Such second detection may set the output state of sensor circuit 100 to low, which may create another timing signal that disables valve 30 and resets sensor circuit 100 .
[0014] FIG. 3 represents one possible logical flow for the operation of a hands-free plumbing device such as a faucet. In such an embodiment, the plumbing device 20 may use the proximity sensor 30 of the circuit 100 . As shown in FIG. 3 , the control circuit 110 initializes at step 200 . At 210 , the proximity sensor 30 may determine if an object has been placed within a predetermined proximity to faucet 20 . If it is determined that no object is within the sensing field of proximity sensor 30 , the process loops to point 212 and repeats step 210 . When an object is found within the sensing field of proximity sensor 30 , the logical control 110 may enable the valve 130 to start the flow of water at step 214 . After a short delay at step 216 , the proximity sensor 30 may be recalibrated at step 218 and the logic control 110 may start a first automatic timer at step 220 .
[0015] At step 230 , the proximity sensor 30 may determine if an object has been placed in proximity to the faucet 20 . If no object is detected within the sensing field of the proximity sensor 30 , the process loops to point 232 to determine if the first automatic timer has expired. If the automatic timer has not expired, the logical control 110 loops back to step 230 . If the automatic timer has expired or an object is found within the sensing field of proximity sensor 30 , the logical control 110 proceeds to step 234 and disables the valve 130 , stopping the flow of water. After a short delay at step 236 , the logical control 110 moves to point 238 and recalibrates the proximity sensor 30 . Subsequently, the logical control 110 proceeds to the point 212 .
[0016] A person having ordinary skill in the art will understand that the logical flow of the embodiment of the invention may be modified to incorporate additional features. One such alternate logical flow is described in FIG. 4 , which discloses a hands free mode to control the water temperature of a plumbing device. As illustrated in FIG. 4 , at step 214 , the embodiment of the system is modified to include a hot valve and a cold valve, both of which may be enabled or disabled by logic control 110 or another similar control device or circuit. For example at step 220 , a first timer may be started. The hot/cold control shown at step 250 enables and disables the hot and cold valves to control the water temperature. The initial state of the hot/cold control is the warm state. In the illustrated embodiment, the first timer controls the period on which the hot/cold control is active. This permits the user to cycle through the temperature states and select a desired water temperature.
[0017] In the warm state, both the hot valve and the cold valve are enabled, resulting in a mixture of hot and cold water flowing to the plumbing device. The volume of hot and cold water flowing to the plumbing device may be selectively varied, thus, resulting in the ability to selectively control the water temperature.
[0018] For a period of time established by first automatic timer at step 200 , the proximity sensor 30 may attempt to detect objects within the sensor's sensing field. Successful detection of an object causes the hot/cold control shown at step 250 to cycle through several temperature states. The hot/cold control, shown at step 250 , cycles through the warm state, the hot state, and finally the cold state. After changing the state of the hot/cold control at step 250 , the first automatic timer may be reset. When the time period set by first automatic timer expires, the hot/cold control may be disabled and the water temperature cannot be changed. The water flow will then be disabled by either the detection of an object within the sensing field of proximity sensor 30 or the expiration of a time period set by a second automatic timer. If the temperature is changed during the first auto timer period, an appropriate LED may be lit to indicate the water temperature chosen. For example a red LED may be lit to indicate hot temperature and a green LED may be lit to indicate cooler temperature. Such an LED can be on constantly or may be blinking at a rapid rate. When the first auto timer period ends, and the water temperature cannot be changed, the LED may go off or may become a less often blinking indicator (lower duty cycle) to conserve energy. When the water is off, the LED may also be completely off.
[0019] Now referring to FIG. 5 , another feature of the invention may be a quarts timer control. Such an embodiment may include a regulator to control the flow of the water. In this embodiment, for a period of time, proximity sensor 30 attempts to detect objects within the sensing field to enable the quarts timer control, step 260 . Once enabled, a user may use the quarts timer control to set the volume of water to be dispensed to a predetermined volume, e.g., 1 quart, 4 quarts, etc. The quarts timer control may also calculate the volume of water that has already flowed and finally reset the first automatic timer.
[0020] On subsequent detections while the first automatic timer is active, the quarts timer control cycles through water volume to be dispensed and adjusts the regulator accordingly. At the expiration of the time period set by the first automatic timer, the quarts timer control calculates the time required for the desired volume of water to be dispensed and starts the second automatic timer. The flow of water is disabled by either the detection of an object within the sensing field of proximity sensor 30 or the expiration of the time period set by the second automatic timer.
[0021] Another embodiment of the system may optionally be a hands free bathtub faucet and shower-head. Such an embodiment may include proximity sensors in both the faucet and the shower-head. The successful detection of an object within the sensing field of the proximity sensor of either the faucet or the shower head may accordingly enable the flow of water in the appropriate plumbing device. If the activated plumbing device detects an object within the sensing field of the proximity sensor, the plumbing device may accordingly disable the flow of water. However, if the disabled plumbing device detects an object within the sensing field of its proximity sensor, the active plumbing device will be disabled and the next plumbing device will be activated.
[0022] While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. The presently disclosed embodiments are therefore to be considered in all respects illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | 4y
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FIELD OF THE INVENTION
This invention relates to electrically operated fuel injectors that are used in fuel injection systems of internal combustion engines.
BACKGROUND AND SUMMARY OF THE INVENTION
Fuel injectors that are of the type commonly known as top-feed fuel injectors typically comprise a metallic inlet connector tube via which fuel enters the fuel injector. It is also typical to have an elastomeric O-ring disposed around the outside of the inlet connector tube for forming a fluid-tight joint between the fuel injector and a cup, or socket, of a fuel rail into which the inlet connector tube is inserted so that the fuel injector can be supplied with fuel. In order to assure that the O-ring will stay on the inlet connector tube, the inlet connector tube comprises a retainer ring disposed over the O-ring. One common practice is to join the retainer ring to the inlet connector tube, such as by staking. Instead of using a separate retainer ring, It is also known to flare the entrance end of the inlet connector tube radially outwardly so that it will have radial interference with the O-ring. The inlet connector tube also typically contains a filter assembly that is assembled onto its entrance for filtering certain foreign matter from fuel entering the fuel injector.
The present invention relates to an improvement in a fuel injector comprising a new and unique integration of the fuel filtering and O-ring retention functions. The invention provides advantage over prior fuel injectors in a number of ways: it reduces the number of individual parts; it reduces the risk of contaminant generation; it facilitates assembly; and it can provide for fuel injector identification by color-coding.
In certain prior constructions, the filter assembly comprised a metal collar press-fitted to the entrance of the inlet connector tube. Such metal-to-metal pressing has the potential for generating undesired contaminant that could adversely affect performance. Such contaminant would be additional to any contaminant generated by operations used to join the retainer ring to the inlet connector tube. The press-fitting of the filter assembly to the inlet connector tube may also make it difficult to accurately control the filter assembly's insertion depth into the inlet connector tube. The present invention avoids these potential disadvantages.
Details of the invention, along with its general and specific principles, will appear in the ensuing description and claims which are accompanied by a drawing. The drawing discloses a presently preferred embodiment of the invention according to the best mode contemplated at this time for carrying out the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is longitudinal view of a representative fuel injector, but containing the invention.
FIG. 2 is an enlarged fragmentary cross sectional view in the direction of arrows 2--2 in FIG. 1.
FIG. 3 is an enlarged fragmentary view of a portion of FIG. 2.
FIG. 4 is a view similar to FIG. 2 showing an alternate form.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The drawing FIGS. 1-3 show an electrically operated top-feed fuel injector 10 comprising a body 12 having a tubular-walled inlet connector tube 14 at one axial end via which fuel is introduced into the fuel injector and a nozzle 16 at the opposite axial end via which fuel is injected from the fuel injector. Inlet connector tube 14 is metal and has an entrance 18 through which fuel passes upon entering. Body 12 comprises a non-metallic cover 20 covering at least an upper portion of the body, including covering inlet connector tube 14 to a point short of entrance 18 so as to leave an axially-facing shoulder 22 that axially faces, but is spaced from, entrance 18. An elastomeric O-ring seal 24 is disposed around the outside of inlet connector tube 14 axially between entrance 18 and shoulder 22, and a filter-retainer assembly 26 is assembled onto inlet connector tube 14 at entrance 18 for both filtering certain entrained matter from fuel entering the entrance and retaining O-ring 24 on tube 14.
Filter-retainer assembly 26 comprises filter media, in the form of a screen mesh, 28 carried by a frame 30. Frame 30 is preferably fabricated of fuel-tolerant, injection-molded plastic and comprises a ring 32 having a radially inwardly facing I.D. surface 34, a radially outwardly facing O.D. surface 36, and axially facing surfaces 38, 40 joining the I.D. and O.D. surfaces 34, 36. Surface 40 fits over the wall of inlet connector tube 14 at entrance 18 so that I.D. surface 34 is radially inwardly of the wall of tube 14 and O.D. surface 36 is radially outwardly of the wall. Surface 40 comprises an axially open circular annular groove 42 within which the wall of tube 14 is received at entrance 18. Frame 30 comprises means providing for the snap-on, snap-off attachment of filter-retainer assembly 26 to the tube. Ring 32 disposes O.D. surface 36 sufficiently radially outwardly to radially overlap O-ring 24, thereby presenting an interference for keeping the O-ring on tube 14.
Inlet connector tube 14 provides for the snap-on, snap-off attachment of filter assembly 26 to the inlet connector tube by means of mutually interlocking tongues and grooves. A radially inwardly directed tongue 43 of frame 30 is received in a radially Outwardly open groove 44 in inlet connector tube 14 while a radially outwardly directed tongue 46 of tube 14 is received in a radially inwardly open groove 48 in frame 30. Each tongue and groove is circumferentially continuous, but may alternatively be discontinuous such that there are multiple discrete tongues and grooves at various locations around the circumference providing multiple individual snap-locks. The material of frame 30 has a certain flexibility that allows its tongue (or tongues) to flex in order for it to snap on and off tube 14 with relatively low installation and removal forces. FIG. 2 shows the filter screen in a surface-mount configuration while FIG. 4 shows an inserted screen configuration. Because of the snap-on, snap-off feature with the accompanying positive abutment stop upon installation, the insertion depth of the filter media into tube 14 can be accurately controlled. The injection molding of 30 frame allows for it to be readily colored to a particular color-coding for identifying a particular size of filter-retainer assembly. | 4y
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This is a continuation of international application Ser. No. PCT/DE00/00245, filed Jan. 28, 2000, which was published in German.
TECHNICAL FIELD
The present invention relates to a profile-connecting device for connecting two profile bars, in particular made of light metal, of which a first profile bar has an end side butting against a longitudinal side of a second profile bar, at least that outer longitudinal side of the second profile bar which is directed toward the end side of the first profile bar and at least one outer longitudinal side, in particular two mutually opposite outer longitudinal sides, of the first profile bar having an undercut groove.
Such profile bars, in particular in the form of aluminum profile bars, with outer grooves are frequently joined together in the industrial sector to form load-bearing structures for equipment.
PRIOR ART
For the assembly of aluminum profiles, a number of connections in the case of which at least one profile, in some cases both profiles, have to be machined, i.e. provided with bores or milled recesses, are known. In addition to the machining costs, the profile elements provided are often difficult and thus expensive to produce.
In addition, the profile machining usually weakens the strength of the profiles precisely in the connection region. In the case of some of the known connections, the tightening or connecting moment is non-uniform and thus is not optimum.
The self-tapping screws used for a fair number of profile-connecting devices shift the machining problem to the assembly stage.
EP-B1-0 460 360 discloses a profile-connecting device of the type mentioned in the introduction. In this case, a flange is connected to at least one sliding block, which is screwed in an inner chamber of the first profile bar via a screw. In the axial direction of the groove of the first profile bar, the flange is then screwed, via a screw-connection element, to sliding blocks arranged in the groove of the second profile bar.
EP-0 233 525 also discloses a profile-connecting device which uses a flange which is screwed in the inner chamber of the first profile via a screw, an arresting part having been introduced in the inner chamber beforehand and secured there in a form-fitting and/or force-fitting manner.
DESCRIPTION OF THE INVENTION
Taking the abovementioned prior art as the departure point, the technical problem or the object on which the present invention is based is to avoid the disadvantages specified in the prior art and to specify a profile connector which ensures a stable connection between the profiles with a uniform tightening or retaining moment without any machining of the profiles. An additional intention is to allow quick installation of the connection, which can be introduced directly in the connection region without preliminary machining of the profiles being necessary.
A further technical problem is to specify a profile-connecting device which can also be introduced subsequently into an existing structure without the existing structure having to be dismantled.
The profile-connecting device according to the invention is provided by the features of independent claim 1. Advantageous configurations and developments form the subject matter of the dependent claims.
Accordingly, the profile-connecting device according to the invention of the type mentioned in the introduction is characterized by a clamping unit which, at least in certain regions, has an outer contour which can be clamped in the groove by virtue of being widened, a screw unit which can be introduced into a continuous cutout of the clamping unit, and a threaded unit which can be introduced with rear-engagement action into the groove of the second profile bar, the clamping unit being spread apart, and thus clamped in the groove of the first profile bar, by virtue of the screw unit, which is introduced into the clamping unit, being screwed into the threaded unit, and a partially clamping and partially form-fitting connection between the two profile bars being produced in conjunction with the threaded unit, via the screw unit.
A particularly advantageous development of the profile-connecting device according to the invention is distinguished in that the screw unit is designed as a wedge screw with flanks which are inclined in certain regions, and the clamping unit has correspondingly inclined mating flank regions, a particularly advantageous configuration being distinguished in that the inner contour of the mating flank regions of the clamping unit is formed with a self-locking slope, this making it possible to ensure a permanently reliable connection.
A particularly preferred alternative configuration is distinguished in that the clamping unit has a base plate with a width which corresponds to the groove width of the profile bar, and at least two clamping elements, which can be spread apart by the threaded unit, are integrally formed on the base plate, flush with the outside of the latter, with the result that, in the non-spread-apart state, the clamping unit can be pushed at least into the groove of the first profile bar and/or, in certain regions, into the groove of the second profile bar. Since the clamping unit has the same width as the groove of the profile bar, screwing the screw unit into the threaded unit, in addition to the spreading action, causes the profiles to be centered automatically as soon as the screw connection engages with the threaded unit, which may preferably be a hammer nut.
A configuration which is particularly preferred in terms of production and straightforward handling is distinguished in that the clamping elements each have a shoulder which, in the inserted and spread-apart state of the clamping unit, engages, at least in certain regions, behind the groove of the first profile bar, and, in one development, the shoulder depth increases from the base plate to the opposite end region of the clamping elements, that is to say it is possible to set a very high clamping pressure, when the clamping unit is spread apart, in the regions adjoining the base plate.
The regions which, in the inserted and spread-apart state, butt against the groove wall within the opening width contain knurling, as a result of which the clamping force can be reliably increased.
A possible material for the clamping unit and/or centering unit is preferably an aluminum/zinc pressure die casting or steel.
The clamping unit and/or centering unit may also be in the form of a precision forging.
As the threaded unit, use is preferably made of a hammer nut or of a sliding block, in particular a spring-activated sliding block.
A configuration which is advantageous particularly in terms of the connection forces and moments transmitted is distinguished in that in each case one clamping unit with centering and screw unit is arranged in the two mutually opposite grooves of the first profile unit, the screw unit being screwed into in each case one threaded unit or, alternatively, into a common threaded unit, which has two bores corresponding to the spacing between the two grooves.
Straightforward and quick installation is further assisted, in an advantageous configuration, in that the screw unit, on the top side, has a contour for the engagement of a tool, which contour is preferably in the form of a polygonal socket contour.
Further embodiments and advantages of the invention can be gathered from the features additionally given in the claims and from the exemplary embodiments specified hereinbelow. The features of the claims may be combined with one another in any desired manner provided that they are not obviously mutually exclusive.
BRIEF DESCRIPTION OF THE DRAWING
The invention and advantageous embodiments and developments of the same are explained and described in more detail hereinbelow with reference to the example illustrated in the drawing. The features which can be gathered from the description and the drawing can be used according to the invention individually or in any desired combination. In the drawing:
FIG. 1 shows an exploded schematic illustration, in perspective, of a clamping unit with screw unit and threaded unit for connecting a first and a second profile bar (detailed), and
FIGS. 2 a ) and b ) show schematic sectional illustrations through the first profile bar with a plan view of the clamping unit according to FIG. 1 in the groove of the second profile bar in the inserted state a) and in the spread-apart, connecting state b).
METHODS OF IMPLEMENTING THE INVENTION
FIG. 1 illustrates two profile bars 20 , 30 which are connected to one another at right angles. A first profile bar 20 , coming from the top, has its end side connected to an outer surface of a profile bar 30 , which is arranged horizontally in FIG. 1 . Both profile bars 20 , 30 are in the form of aluminum profile bars which have a square outer peripheral contour, a respective longitudinally continuous groove 22 or 32 being provided on each outer side.
The connection takes place via a profile-connecting device 10 , which is constructed as follows:
First of all each profile-connecting device 10 has a clamping unit 13 , which has two clamping elements 13 . 1 , 13 . 2 .
In their top region, the clamping elements 13 . 1 have an inwardly inclined mating flank region 26 . With the elements 13 . 1 , 13 . 2 inserted into the groove 22 , it is possible to introduce between the two clamping elements 13 . 1 , 13 . 2 a screw unit 14 which has an external thread 36 , is designed as a wedge screw and has flanks 24 which are likewise inclined correspondingly to the mating flank regions 26 of the clamping elements 13 . 1 , 13 . 2 and, in the inserted state, come into abutment with the mating flanks 26 .
The head of the screw unit 14 , on the top side, has a hexagonal socket contour 28 for the engagement of a tool.
The profile-connecting device 10 also has a threaded unit 16 which, in the exemplary embodiment, is designed as a known hammerhead nut with an internal thread 34 and can be inserted into the groove 32 of the second profile bar 30 , with rear engagement of the groove 32 .
In an exemplary embodiment which is not illustrated, use is made of a threaded element which passes through the entire groove 32 and, corresponding to the spacing between the two screw units and/or the grooves 22 of the first profile bar, has bores with threads at the same spacing.
The clamping unit 13 , on the underside, has a base plate 50 of width B which corresponds to the groove width B of the first profile bar 20 and of the second profile bar 30 . The two separate clamping elements 13 . 1 are integrally formed on the top side of the base plate 50 , and do not project beyond the width B. These two clamping units 13 . 1 , in their interior, form a continuous cutout 27 with a corresponding mating flank 26 for the flank 24 of the screw-connection unit 14 .
The clamping elements 13 . 1 , 13 . 2 , on the outside, have a shoulder 52 which increases in depth from the base plate 50 to the mutually opposite end border. This results in an inclined surface which, according to the exemplary embodiment illustrated, contains transverse ribs or knurling 54 .
As threaded unit 16 , use is made of a hammer nut 16 , which is known as such and can then easily be inserted into groove 32 of the second profile bar 30 . By virtue of the screw unit 14 being turned, the hammer nut 16 initially turns along with it and then swings round in the groove 32 of the second profile bar 30 .
The screw-connection unit 14 , the clamping unit 13 and the threaded unit 16 can form a preassembled installation unit by virtue of the screw-connection unit 14 being screwed into the internal thread 34 of the threaded unit 16 to a slight extent, with the result that the clamping elements 13 . 1 of the clamping unit 13 are not spread apart. In this preassembled state, it is possible for the connecting device 10 , with the hammer nut 16 in an appropriate position, to be introduced into the groove 32 . This position is illustrated in FIG. 2 a ). Since, in this state, the base plate 50 engages, in certain regions, in the groove 32 of the second profile bar 30 , a certain centering action has already been provided for in this preassembled state. The connecting device 10 is then pushed along the groove 32 into the groove 22 of the first profile bar. This is possible since the outer dimensions of the clamping unit 13 do not exceed the dimensions of the groove. If the screw-connection unit 14 is then turned, the hammer nut 16 initially turns in the groove 32 until, finally, it swings round. Further turning of the screw-connection unit 14 forces the flank 24 of the latter onto the corresponding mating surface 26 of the clamping elements 13 . 1 , as a result of which said clamping elements 13 . 1 are spread apart laterally. In the final spread-apart state of the clamping elements 13 . 1 , the arrangement is such that the two stop surfaces 52 engage, at least in certain regions, behind the inner wall of the groove 22 , with the result that, in this state, it is no longer possible, as a result of the form fit, for the connecting device 10 to be drawn out of the groove 22 . At the same time, the clamping elements 13 . 1 of the clamping unit 13 are forced apart from one another, with the result that those surfaces of the clamping elements 13 . 1 which are located in front of the shoulder 52 in each case are pressed with clamping action, by way of the knurling 54 , against the wall of the opening of the groove 22 .
The profile-connecting device 10 illustrated provides an assembly aid by means of which two profile bars 20 , 30 , with grooves 22 , 32 , which are positioned perpendicularly one upon the other are connected reliably and in the case of which it is not necessary for installation parts to be introduced from the free end sides of the groove 22 or 32 or for possible bores to be produced. The assembly operation is extremely straightforward and a permanently reliable connection is ensured. | 4y
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This is a division of application Ser. No. 411,178 filed on Sept. 22, 1989, now U.S. Pat. No. 4,971,719.
This invention relates to optical films incorporating birefringent nematic and chiral nematic liquid crystal materials. More particularly, this invention relates to thin optically responsive films of electron beam cured polymers incorporating a dispersion of microdroplets of such liquid crystal materials.
BACKGROUND OF THE INVENTION
As liquid crystal devices find wider application, there is motivation to develop new and easier ways to make or use packages of these special materials. It is now known that some liquid crystal materials and certain liquid polymer precursors may be mixed together, the mixture formed into a film, and the polymer precursor materials allowed to react and cure. The resulting product is a polymer film that contains dispersed or encapsulated therein, many very small drops of liquid crystal material. Depending upon the nature of the liquid crystal material, the film may be opaque at room temperature. However, when that film is heated, stressed, or subjected to an electrical or magnetic field across its thickness, those portions of the film tend to become transparent.
Dispersion of liquid crystal material in a cured polymer matrix film is a convenient package for working with the liquid crystals. There have been several methods proposed for forming these films, including thermal cure, ultraviolet cure, phase separation by cooling a thermoplastic-polymer/liquid crystal mixture, and evaporation of solvent from a thermoplastic/liquid crystal solution. However, there are shortcomings associated with each of these known methods for forming these polymer-dispersed liquid crystal films.
Generally, when using a thermal cure such as with thermoset materials which cure by cross-linking, the polymer precursors must be handled in two parts to avoid premature curing. In addition, commonly used liquid crystal materials usually cannot tolerate high temperatures. Therefore, the polymer precursors must be chosen to be curable at about room temperature. Further, once all ingredients are mixed, the cure begins and the cure is relatively slow which leads to handling problems and aging problems in the polymer film.
The use of ultraviolet curing methods is also not ideal, since this method requires the addition of photoinitiators to the film. These photoinitiators may result in shortened film life unless special, non-trivial protective steps are taken.
Lastly, there are problems associated with the use of the thermoplastic-based films for producing the final film. The thermoplastic-based films and their physical characteristics such as refractive index, are extremely temperature sensitive since they are not cross-linked. In addition, high temperature usage of these thermoplastic films are limited because of undue softening and melting of the film. Lastly, because of the nature of the way these films are prepared, essentially by freezing or evaporation of a solvent, the resulting films are typically characterized by non-uniform thickness and properties.
Therefore, it is desirable to provide a method for curing these polymer films having the liquid crystal materials dispersed throughout. It is further desirable that such method avoid and alleviate the shortcomings associated with the previous methods.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method for forming thin films of polymer-dispersed liquid crystal material utilizing specific electron beam curable polymeric precursor materials.
It is a further object of the present invention to provide a method for rapidly preparing an electron-beam cured polymer film of dispersed liquid crystal materials that may be formed between flat glass or plastic optical plates or upon another suitable substrate, which can be accomplished by premixing liquid materials, and later at a time of choice rapidly and substantially completely curing the films with electron beam irradiation at room temperature or other desired temperature to minimize handling problems as well as degradation or other side reactions with the dispersed liquid crystal material.
It is still a further object of this invention to provide a method for forming a polymer film containing droplets of suitable nematic or chiral nematic type liquid crystal materials such that the film is opaque in one mode of operation and transparent in another mode.
In accordance with a preferred embodiment of this invention, these and other objects and advantages are accomplished as follows.
An optically responsive polymer dispersed liquid crystal film using electron beam curing techniques is prepared. The film contains birefringent nematic and/or birefringent chiral nematic liquid crystal microdroplets dispersed in a film of an electron beam cured reaction product. The electron beam cured reaction product contains a mercaptan activated allyl compound, preferably triallyl isocyanurate and pentaerythritol tetrakis(2-mercapto-propanoate).
The liquid crystal microdroplets display positive dielectric anisotropy and/or positive diamagnetic anisotropy, thereby being capable of undergoing repeated thermally, electrically or magnetically induced transitions between opaque and transparent states.
Also comprehended by this invention is the method for making such a polymer dispersed liquid crystal film. First, the liquid crystal material, preferably birefringent nematic and/or birefringent chiral nematic liquid crystals, is mixed with the electron-beam curable liquid precursor mixture. The electron-beam curable liquid precursor mixture is a mercaptan activated allyl compound, preferably of the type described above. Then the mixture is cured in the form of a film with a focused electron beam to thereby form a cured polymer matrix having therein droplets of liquid crystal material displaying positive dielectric anisotropy and/or positive diamagnetic anisotropy.
Utilizing electron beam curing methods for forming polymer dispersed liquid crystal films has many advantages, such as a rapid cure, controlled cure processing parameters, and relatively temperature-incentive refractive index in the resultant film, while avoiding the shortcomings associated with the previous methods such as the use of a photoinitiator in the matrix material Therefore, it is possible to use simpler matrix materials than were required for the previous curing methods.
Other objects and advantages of this invention will be better appreciated from a detailed description thereof, which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other advantages of the invention will become more apparent from the following description taken in conjunction with the accompanying drawings wherein like references refer to like parts and wherein:
FIG. 1 is a schematic view in cross-section and greatly enlarged of a liquid crystal-containing film of this invention, and
FIG. 2 is a schematic view in enlarged cross section of the film disposed between two transparent plates.
DETAILED DESCRIPTION OF THE INVENTION
Utilizing our electron beam curing methods for forming polymer dispersed liquid crystal films has many advantages, such as a rapid cure, controlled cure processing parameters, and relatively temperature-insensitive refractive index in the resultant film. In addition, our curing method eliminates the shortcomings associated with other methods such as the use of a photoinitiator in the matrix material. Therefore, it is possible to use simpler matrix materials than were required for the previous curing methods.
Various combinations of the electron beam-curable polymer precursor matrix formulations, liquid crystal compositions, substrates and electron beam dosages were tried to determine the optimum combination.
Although only two types of substrates were utilized to fabricate the electron beam cured polymer dispersed liquid crystal films, four were evaluated for their propensity to discolor upon exposure to the electron beam irradiation. The four types of substrates tested for discoloration due to the electron beam irradiation were polyethylene terephthalate (polyester), glass, flexible glass and epoxy. The polyester (PET) was the only substrate which did not discolor significantly, whereas the others did. Only the polyester and flexible glass were used to actually form the electron beam cured polymer dispersed liquid crystal films. Because the polyester did not tend to discolor, coupled with the need for fully flexible substrates for large scale fabrication requirements, the polyester is the preferred substrate for use in these electron beam cured films.
Three different types of liquid crystal compositions were utilized. Generally, the three liquid crystal mixtures contained biphenyl, terphenyl, cyclohexyl, and/or pyrimidine compounds. More particularly, the three commercially available mixtures which were employed were E7 and E63 available from EM Industries, Hawthorne, NY, and ROTN404 available from Hoffman-LaRoche, Nutley, NJ.
The E7 liquid crystal mixture contains approximately:
51 weight percent of the commonly known liquid crystal component 5CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-pentyl;
25 weight percent of the commonly known liquid crystal component 7CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-heptyl;
16 weight percent of the commonly known liquid crystal component 80CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-octyloxy; and
8 weight percent of the commonly known liquid crystal component 5CT having the chemical name [1,1',4'-1"-Terphenyl],4-carbonitrile,4"pentyl.
The E63 liquid crystal mixture is similar to the E7 mixture with added cyclohexanes. It contains:
significant amounts of the commonly known liquid crystal component 5CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-pentyl;
significant amounts of the commonly known liquid crystal component 7CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-heptyl;
lesser amounts of the commonly known liquid crystal component 5CT having the chemical name [1,1',4'-1"-Terphenyl],4-carbonitrile,4"pentyl;
lesser amounts of the commonly known liquid crystal component PCH3 having the chemical name Benzonitrile,4-(4 propyl-1-cyclohexen-1-yl);
lesser amounts of the commonly known liquid crystal component BCH5 having the chemical name [1,1'Biphenyl]-4-carbonitrile,4'(4-pentyl-1-cycl ohexen-1-yl); and
still lesser amounts of the commonly known liquid crystal component DB71 having the chemical name [1,1'-Biphenyl]-4-carboxylic acid, 4'-heptyl-4'-cyano[1,1'-biphenyl]-4-yl ester.
The ROTN404 liquid crystal mixture is also similar to the E7 mixture with added pyrimidines. It contains approximately:
30 weight percent of the commonly known liquid crystal component 50CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-pentyloxy;
15 weight percent of the commonly known liquid crystal component 80CB having the chemical name [1,1'Biphenyl],4-carbonitrile,4'-octyloxy;
10 weight percent of the commonly known liquid crystal component 5CT having the chemical name [1,1',4'-1"-Terphenyl],4-carbonitrile,4.increment.pentyl;
10 weight percent of the commonly known liquid crystal component RO-CP-7035 having the chemical name Benzonitrile,4-(5-pentyl-2-pyrimidimyl)-;
20 weight percent of the commonly known liquid crystal component RO-CP-7037 having the chemical name Benzonitrile,4-(5-heptyl-2-pyrimidimyl)-; and
15 weight percent of the commonly known liquid crystal component RO-CM-7334 having the chemical name Benzonitrile,4-[5-(4-butylphenyl)-2-pyrimidimyl]-.
Four different electron beam-curable polymer precursor matrix formulations were tested. The four formulations contained various combinations of six different individual polymer components. The six individual polymer components are as follows.
NOA65, which is commercially available as Norland Optical Adhesive from Norland Products, New Brunswick, NJ contains approximately 56 percent triallyl isocyanurate, approximately 41 percent pentaerythritol, tetrakis(2-mercapto-propanoate) and approximately 4 percent benzophenone.
NUVOPOL EMBO is a photoaccelerator commercially available from Aceto Chemical Co., Inc., Flushing, NY. Qualitatively, it contains 4-dimethylamino benzoic acid and ethyl ester.
PHOTOMER 5007 is a diacrylate oligomer commercially available from Diamond Shamrock, Morristown, NJ.
PHOTOMER 6008 is a diurethane diacrylate commercially available from Diamond Shamrock, Morristown, NJ.
DUDMA is single component diurethane dimethacrylate commercially available from Polysciences, Inc., Washington, PA.
PETA is single component pentaerythritol tetraacrylate commercially available from Polysciences, Inc., Washington, PA.
The four polymer matrix formulations incorporating the various combinations of these six individual polymers utilized to form the electron beam-curable polymer precursor are as follows.
Formulation A is a mixture of the NOA65 polymer plus approximately 2 volume percent NUVOPOL. This formulation is a mercaptan-activated allyl system.
Formulation B is a mixture of approximately two volume parts P5007 polymer with approximately 1 volume part PETA. Formulation B is an acrylate.
Formulation C is a mixture of approximately two volume parts P6008 polymer with approximately 1 volume part PETA. Formulation C is an acrylate.
Formulation D is a mixture of approximately two volume parts DUDMA polymer with approximately 1 volume part PETA. Formulation D is a methacrylate.
The electron beam curing process is produced by breaking the monomer bonds within the polymer matrix formulation by the energetic electrons. The cure times required are a function of the organic system employed, with acrylates requiring less cure time than the methacrylates, which require less cure time the allyls. All four electron beam-curable polymer precursor formulations were electron beam cured with different combinations of the liquid crystal compositions and substrates, with varying degrees of success achieved.
FIG. 1 illustrates a film 10 of the electron beam cured polymer matrix 12 having microdroplets 14 of liquid crystal material therein.
FIG. 2 illustrates the film 10 of FIG. 1 sandwiched between two transparent substrates 16. A transparent conductive coating 18, preferably indium-tin oxide, however, other materials such as tin oxide, gold or silver may also be used, is provided between the electron beam cured film 10 and each transparent substrate 16, so as to contact the electron beam cured film 10.
The electron accelerator utilized was an Electrocurtain Model P250S processor with Selfshield web handling assembly available from Energy Sciences, Inc., Woburn, MA. The electron accelerator was operated at approximately 250 kiloVolts. Sample dosages in the range from approximately 5 to 20 Megarads were obtained by varying the electron beam current from approximately 2 to 10 milliAmps. To determine the optimum electron irradiation dosages it was necessary to correct for electron energy loss in the top substrate 16 of the sandwiched structure shown in FIG. 2. Further, the dosages are dependent on the density of the electron beam cured polymer dispersed liquid crystal film 10. At 250 kiloVolts operating voltage, the penetration depth was approximately 12 mils at which the dosage was 50 percent of the maximum. The unregulated cure temperature was approximately 50° C., which was the temperature of the baseplate. The film samples were exposed to the electron dosage by means of a conveyor belt moving at approximately 10 feet/minute.
The preferred combination of substrate material, liquid crystal material, electron beam curable polymer precursor matrix formulation and electron beam dosages is as follows. One volume part formulation A electron beam curable polymer precursor matrix to one volume part ROTN404 liquid crystal material is premixed and may be allowed to stand theoretically indefinitely before exposure to the electron beam irradiation; however, in practice one would want to limit the amount of time before curing so as to avoid any detrimental aging effects. The mixture is then sandwiched between two PET substrates. A suitable transparent conductive coating is provided between the substrates and intermediate mixture of polymer precursor matrix and liquid crystal material. The sandwiched structure was exposed to an optimum electron dosage of approximately 10 Megarads. The thickness of the polymer-dispersed liquid crystal film is approximately 41 microns nominally. The liquid crystal droplets were determined by Scanning electron microscopy to have a nominal diameter of approximately 0.7 microns.
The resulting films were characterized by being milky white opaque at room temperature. However, when the films were heated to the nematic-isotropic phase transition temperature of the liquid crystal material of approximately 80° C., they abruptly became clear and transparent. Our films remained clear at temperatures above about 80° C., but returned to a milky opaque condition when cooled below that temperature.
The transparent conductive electrodes were connected to an electrical source and had applied 100 volts, 60 cycle AC. This electrical stimulation resulted in the opaque film becoming clear and transparent. When the voltage was removed, the films again virtually instantaneously became opaque. Further, when the films are subjected to applied mechanical stress, they also exhibit this change between opaque and transparency to varying degrees. Notably, the transparent state was capable of polarizing the incident light in the direction of polarization perpendicular to the stress direction.
Other combinations of the liquid crystal materials, electron beam curable polymer precursor matrix, substrate and electron beam dosages were tried with the resulting optical properties ranging from fair to good. Those combinations were as follows.
Example 2
Approximately one volume part ROTN404 liquid crystal material mixed with approximately one volume part Formulation A polymer precursor. The mixture was sandwiched between transparent polyester substrates. An electron dosage of approximately 20 Megarads was utilized. The resulting sandwiched structure had a film thickness of approximately 48 microns. In the off state, the film exhibited very good light scattering properties. Further, it was characterized by good thermo-optic response and stress induced optic response, but poor electro-optic response.
Example 3
Approximately 0.75 volume part ROTN404 liquid crystal material mixed with approximately one volume part Formulation A polymer precursor. The mixture was sandwiched between polyester substrates. An electron dosage of approximately 20 Megarads was utilized. In the off state, the film exhibited fair light scattering o properties.
Example 4
Approximately one volume part ROTN404 liquid crystal material mixed with approximately one volume part Formulation B polymer precursor. The mixture was sandwiched between polyester substrates. An electron dosage of approximately 5 Megarads was utilized. The resulting sandwiched structure had a film thickness of approximately 64 microns. In the off state, the film exhibited good light scattering properties. It was characterized by poor electro-optic response and good thermo-optic response. The films were too rigid to measure an optic response to induced stress. It is believed that the film was not completely cured due to the excessive thickness of the film. It is believed that if the thickness were reduced, the stress-induced optic response would improve.
Example 5
Approximately one volume part ROTN404 liquid crystal material mixed with approximately one volume part Formulation B polymer precursor. The mixture was sandwiched between polyester substrates. An electron dosage of approximately 10 Megarads was utilized. The resulting sandwiched structure had a film thickness of approximately 77 microns. In the off state, the film exhibited very good light scattering properties. It was characterized by poor electro-optic response, good thermo-optic response and again was too rigid due to excessive thickness of the film to optically respond to applied stress.
Example 6
Approximately one volume part ROTN404 liquid crystal material mixed with approximately one volume part Formulation B polymer precursor. The mixture was sandwiched between polyester substrates. An electron dosage of approximately 20 Megarads was utilized. The resulting sandwiched structure had a film thickness of approximately 74 microns. In the off state, the film exhibited very good light scattering properties. It was characterized by poor electro-optic and thermo-optic responses probably due to the large film thicknesses or rigidity. The stress-induced optic response was also poor due to, it is believed, the excessive thicknesses.
Example 7
Approximately one volume part E63 liquid crystal material mixed with approximately one volume part Formulation D polymer precursor. The mixture was sandwiched between polyester substrates. An electron dosage of approximately 10 Megarads was utilized. In the off state, the film exhibited good light scattering properties. It was characterized by fair electro-optic response and good thermo-optic response.
Example 8
Approximately one volume part E63 liquid crystal material mixed with approximately one volume part Formulation D polymer precursor. The mixture was sandwiched between polyester substrates. An electron dosage of approximately 20 Megarads was utilized. In the off state, the film exhibited very good light scattering properties. It was characterized by fair electro-optic response and good electro-optic.
Example 9
Approximately one volume part ROTN404 liquid crystal material mixed with approximately one volume part Formulation C polymer precursor. The mixture was sandwiched between flexible glass substrates. An electron dosage of approximately 6.25 Megarads was utilized. In the off state, the film exhibited fair light scattering properties. It was characterized by poor thermo-optic response and again was too rigid to determined an optic response to applied stress.
Example 10
Approximately one volume part E7 liquid crystal material mixed with approximately one volume part Formulation B polymer precursor. The mixture was sandwiched between flexible glass substrates. An electron dosage of approximately 12.5 Megarads was utilized. In the off state, the film exhibited good light scattering properties, and was characterized by poor thermo-optic response and rigid optic response to applied stress.
Therefore, the electron beam cured polymer-dispersed liquid crystal films exhibit great utility, yet are formed without the disadvantages associated with the previous methods for forming these films. The films are opaque at room temperature but are readily converted to a transparent film by the application of heat, a suitable electrical potential or applied stress. Clearly by adjusting the indices of refraction of the polymer and the liquid crystal via dissolving suitable materials, or by optimizing the film thickness, one can optimize the temperature driven effects or the electric or magnetic driven effects. In addition, one skilled in the art may choose to use our electron beam curing method with liquid crystals having a smectic molecular structure, or use further techniques to achieve memory effects in the films, or alternatively, one may choose to use our method of electron-beam treatment for treatment of polymer dispersed liquid crystal films which have been prepared by other techniques for enhancement of their properties, such as reduced temperature sensitivity of the refractive index. The films may be formed easily and rapidly with our method, even in large area configurations. Obviously such a film could be adapted as a display, a light shutter or a temperature sensing device.
While our invention has been described in terms of a few specific examples, it will be appreciated that other forms could readily be adapted by one skilled in the art. Accordingly, the scope of our invention is to be considered limited only by the following claims. | 4y
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This application claims benefit pursuant to 35 U.S.C. §119(e) of Provisional Application 61/465,240 filed Mar. 16, 2011, the disclosure of which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
This invention relates to automated banking machines that operate responsive to data read from user cards and which may be classified in U.S. Class 235, Subclass 379.
BACKGROUND ART
Automated banking machines may include a card reader that operates to read data from a bearer record such as a user card. Automated banking machines may operate to cause the data read from the card to be compared with other computer stored data related to the bearer or their financial accounts. The machine operates at least in part in response to the comparison determining that the bearer record corresponds to an authorized user and/or an authorized financial account, to carry out at least one transaction which may be operative to transfer value to or from at least one financial account. A record of the transaction is often printed through operation of the automated banking machine and provided to the user. Automated banking machines may be used to carry out transactions such as dispensing cash, the making of deposits, the transfer of funds between accounts and account balance inquiries. The types of banking transactions that may be carried out are determined by the capabilities of the particular banking machine and system, as well as the programming of the institution operating the machine. Other types of automated banking machines may be operated by merchants to carry out commercial transactions. These transactions may include, for example, the acceptance of deposit bags, the receipt of checks or other financial instruments, the dispensing of rolled coin, or other transactions required by merchants. Still other types of automated banking machines may be used by service providers in a transaction environment such as at a bank to carry out financial transactions. Such transactions may include for example, the counting and storage of currency notes or other financial instrument sheets, and other types of transactions. For purposes of this disclosure an automated banking machine, automated transaction machine or an automated teller machine (ATM) shall be deemed to include any machine that may be used to automatically carry out transactions involving transfers of value.
Automated banking machines may benefit from improvements.
OBJECTS OF EXEMPLARY EMBODIMENTS
It is an object of an exemplary embodiment to provide a banking system apparatus that is operated responsive to data bearing records.
It is an object of an exemplary embodiment to provide an automated banking machine.
It is a further object of an exemplary embodiment to provide an automated banking machine that has an attractive appearance.
It is a further object of an exemplary embodiment to provide an automated banking machine which is more readily serviced.
It is a further object of an exemplary embodiment to provide an automated banking machine which is more readily manufactured.
It is a further object of an exemplary embodiment to provide a method for more efficiently manufacturing an automated banking machine.
It is a further object of an exemplary embodiment to provide a method for servicing an automated banking machine which requires less space for servicing.
It is a further object of an exemplary embodiment to provide a method for servicing an automated banking machine which provides improved access for servicing of internal components.
It is a further object of an exemplary embodiment to provide a method for servicing an automated banking machine which provides more efficient servicing of internal components.
Further objects of exemplary embodiments will be made apparent in the following Detailed Description of Exemplary Embodiments and the appended claims.
The foregoing objects are accomplished in an exemplary embodiment by an automated banking machine which includes a top housing bounding an interior area. The top housing defines a front opening to the interior area and may define a rear opening into the interior area. The top housing is mounted above a secure enclosure which is alternatively referred to herein as a chest portion or safe. The top housing may further include at least one wall, the at least one wall formed to include one or more housing vents operative to enable air to pass therethrough. Such housing vents enable the movement of air, for example, to assist in removing heat generated by components within the housing.
The top housing houses upper banking machine components which may include, for example, all or portions of a display, the card reader, a receipt printer, a keypad, a camera, controllers, processors, including computer processors, actuators, sensors, and other devices. As used herein “keypad” means input keys whether arranged in a keypad arrangement, keyboard arrangement, or otherwise, and the designations are interchangeable unless expressly identified as being used in a restricted manner. The banking machine components may be further enclosed within a case. The case may be formed to include one or more component case vents operative to enable air to pass therethrough. The processor, for example, may be further enclosed in a processor case with processor case vents. Such processor case vents enable the movement of air, for example, to assist in removing heat generated by processor components. The chest houses lower banking machine components which may include, for example, all or portions of a currency dispenser mechanism, a currency recycler, a secure deposit holding container and other devices.
In an example embodiment, an apparatus is provided that includes an automated banking machine that is operative to cause financial transfers responsive at least in part to date read from data bearing records. The automated banking machine includes a card reader that is operative to read card data usable to identify at least one of a user of the machine and a financial account. The machine also includes a housing bounding an interior area. At least one computer including at least one processor is associated with the machine. The computer is in operative connection with the card reader. The computer is operative to cause card data to be read through operation of the card reader and to cause a determination to be made that the card data corresponds to an authorized financial account. Responsive at least in part to the determinations, the at least one computer causes the account to be assessed a value associated with a financial transaction. The machine further includes a device support in operatively supported connection with the housing and moveable between a first position wherein the device support is substantially within the interior area of the housing and a second position wherein at least a portion of the device support extends outside of the housing. The machine also includes at least one slide in operative connection with the device support and the housing. The at least one slide is operative to enable the device support to move between the first position and the second position. One of the housing and the at least one slide includes a first tab and the other one of the housing and the at least one slide includes a first slot. The first tab and the first slot are configured to releasably engage each other. The at least one slide and the housing are configured such that each slide may be mounted to the housing in a first configuration and a second configuration. The first configuration enables the device support to be moved between the first and second positions through an opening at a first side of the housing. The second configuration enables the support to be moved between the first and second position through an opening at a second side of the housing opposed of the first side.
In an example embodiment, the first tab includes a proximal portion and a distal portion. The proximal portion is configured to extend through the first slot and the distal portion is configured to extend in a first direction when the slide is mounted to the housing. The first direction is the direction of movement of the device support from the second position toward the first position.
In a further exemplary embodiment, a method performed in connection with an automated banking machine includes moving a device support in operatively supported connection with a housing of an automated banking machine from a first position wherein the device support substantially within an interior of the housing of the machine to a second position wherein at least a portion of the device support extends through a housing opening. The exemplary method further includes disengaging at least one slide from operative engagement with the housing by moving the slide relative to the housing in a first direction to cause the first tab and the first slot to be disengaged from holding engagement.
Exemplary embodiments may allow ready access to the banking machine components for servicing, as well as simplifying the manufacturing and/or assembly process. The principles described may be applied to numerous automated banking machine configurations.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an isometric view of an automated banking machine of an exemplary embodiment.
FIG. 2 is an isometric view of the automated banking machine of FIG. 1 with a rollout tray extended.
FIG. 3 is a side schematic view of an automated banking machine illustrating various banking machine components.
FIG. 4 is an isometric view of the automated banking machine of FIG. 1 with a lower fascia in an accessible position.
FIG. 5 is an isometric view of the automated banking machine of FIG. 1 with a lower fascia in an accessible position and a chest door in an open position.
FIG. 6 is an isometric view of a top housing for an automated banking machine supporting a rollout tray in an extended position.
FIG. 7 is an isometric rear view of the automated banking machine of FIG. 1 .
FIG. 8 is a side schematic view of an exemplary embodiment of an automated banking machine illustrating the alignment of an upper fascia and a lower fascia.
FIG. 9 is an isometric view of an automated banking machine similar to FIG. 5 showing the chest door selectively engaged with the lower fascia.
FIG. 10 is a schematic view of an alternate embodiment of a chest for an automated banking machine, as viewed from the front.
FIG. 11 is a schematic view of the alternate embodiment of the chest shown in FIG. 10 , as viewed from the rear.
FIG. 12 is an isometric view of a chest door illustrating a locking bolt mechanism.
FIG. 13 is an isometric exploded view of an alternate embodiment of an automated banking machine.
FIG. 14 is an isometric view of a top housing cover, a mounting tray and an upper fascia of an automated banking machine.
FIG. 15 is an isometric view of an alternate embodiment of an automated banking machine.
FIG. 16 is an isometric view, partly in phantom, of an alternate exemplary embodiment of an automated banking machine in an operational condition.
FIG. 17 is an isometric view, partly in phantom, of the automated banking machine of FIG. 16 , in a serviceable condition.
FIG. 18 is an isometric view of an automated banking machine of an exemplary embodiment.
FIG. 19 is a further isometric view of the automated banking machine of the exemplary embodiment shown in FIG. 18 .
FIG. 20 is an isometric view of an automated banking machine of an exemplary embodiment.
FIG. 21 is a plan view of an automated banking machine of an exemplary embodiment.
FIG. 22 is a plan view of an automated banking machine of an exemplary embodiment.
FIG. 23 is an elevation view, partly in phantom, of a portion of an automated banking machine of an exemplary embodiment.
FIG. 24 is an isometric view of an automated banking machine of an exemplary embodiment.
FIG. 25 is a view of a portion of an automated banking machine of an exemplary embodiment illustrating a component case assembled into a top housing.
FIG. 26 is an isometric view of a portion of an automated banking machine of an exemplary embodiment illustrating a component case in combination with a duct assembly.
FIG. 27 is an exploded isometric view of the automated banking machine of the exemplary embodiment of FIG. 26 .
FIG. 28 is an isometric view of a duct assembly portion of an automated banking machine of an exemplary embodiment illustrating the details of the duct assembly.
FIG. 29 is an isometric view of a portion of a duct assembly portion and a portion of a component case portion of an automated banking machine of an exemplary embodiment illustrating the details of the duct assembly and component case.
FIG. 30 is a partial section view taken along the line 30 - 30 of FIG. 26 .
FIG. 31 is an isometric view of a portion of an exemplary automated banking machine illustrating a fascia assembly and a support.
FIG. 32 is an exploded isometric view of a portion of the exemplary automated banking machine of FIG. 31 illustrating the fascia assembly and the support.
FIG. 33 is an isometric view of a portion of an exemplary automated banking machine illustrating portions of a fascia assembly and a support.
FIG. 34 is an isometric view of a portion of an exemplary automated banking machine illustrating portions of a fascia assembly and a support.
FIG. 35 is a front and left side isometric view of a portion of an exemplary automated banking machine illustrating a first slide mounted to the right bracket of the housing of the machine.
FIG. 36 is a front and right side isometric view of the portion of the exemplary automated banking machine of FIG. 35 .
FIG. 37 is a front and right side isometric view of the right bracket of the housing of the exemplary automated banking machine of FIG. 35 .
FIG. 38 is an enlarged front and right side isometric view of the portion of the right bracket as indicated in FIG. 37 .
FIG. 39 is an enlarged front and right side isometric view of the portion of the right bracket as indicated in FIG. 37 .
FIGS. 40 and 41 are rear and left side isometric views of portions of the left bracket of the exemplary automated banking machine of FIG. 35 .
FIG. 42 is an enlarged front and right side isometric view of the portion of the exemplary automated banking machine as indicated in FIG. 36 .
FIG. 43 is an enlarged front and right side isometric view of the portion of the exemplary automated banking machine as indicated in FIG. 36 .
FIGS. 44 and 45 are rear and left side isometric views of portions of the left bracket with the second slide mounted thereto of the exemplary automated banking machine of FIG. 35 .
FIG. 46 is a side schematic view of the exemplary automated banking machine illustrating the rollout tray in the extended position of a rear-loaded configuration.
FIG. 47 is a front and left side isometric view of a portion of the exemplary automated banking machine of FIG. 46 illustrating the second slide mounted to the right bracket of the housing of the machine.
FIG. 48 is a front and right side isometric view of the portion of the exemplary automated banking machine of FIG. 47 .
FIG. 49 is an enlarged front and right side isometric view of the portion of the right bracket as indicated in FIG. 47 .
FIG. 50 is an enlarged front and right side isometric view of the portion of the right bracket as indicated in FIG. 47 .
FIGS. 51 and 52 are rear and left side isometric views of portions of the left bracket with the first slide mounted thereto of the exemplary automated banking machine of FIG. 46 .
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Referring now to the drawings, and particularly to FIGS. 1-2 , there is shown therein an automated banking machine of a first exemplary embodiment, generally indicated 10 . In this exemplary embodiment, automated banking machine 10 is an automated teller machine (ATM). Machine 10 includes a top housing 12 having side walls 14 and 16 , and top wall 18 . Housing 12 encloses an interior area indicated 20 . Housing 12 has a front opening 22 . In this exemplary embodiment, the rear of housing 12 is closed by a rear wall 19 , shown in FIG. 7 . However, in other embodiments, the rear of housing 12 may be accessible through an access door or similar device. Top housing 12 is used to house certain banking machine components such as input and output devices.
With reference to FIG. 3 , in this exemplary embodiment the input devices include a card reader schematically indicated 24 . Card reader 24 is operative to read a customer's card which includes indicia thereon. The indicia may correspond to information about the customer and/or information about a customer's financial account, such as the customer's account number. In some embodiments the card reader 24 may be a card reader adapted for reading magnetic stripe cards and/or so called “smart cards” which include a programmable memory. Other embodiments may read data from cards wirelessly such as radio frequency identification (RFID) cards. Exemplary embodiments may include features of the type discussed in U.S. Pat. No. 7,118,031 the disclosure of which is incorporated herein by reference in its entirety. Another input device in the exemplary embodiment includes input keys 26 . Input keys 26 may in some embodiments, be arranged in a keypad or keyboard. Input keys 26 may alternately or in addition include function keys or other types of devices for receiving manual inputs. It should be understood that in various embodiments other types of input devices may be used such as biometric readers, speech or voice recognition devices, inductance type readers, infrared (IR) type readers, and other devices capable of communicating with a person, article or computing device, radio frequency type readers and other types of devices which are capable of receiving information that identifies a customer and/or their account.
The exemplary embodiment of machine 10 also includes output devices providing outputs to the customer. In the exemplary embodiment machine 10 includes a display 28 . Display 28 may include an LCD, CRT or other type display that is capable of providing visible indicia to a customer. In other embodiments output devices may include devices such as audio speakers, radio frequency (RF) transmitters, IR transmitters or other types of devices that are capable of providing outputs which may be perceived by a user either directly or through use of a computing device, article or machine. It should be understood that embodiments may also include combined input and output devices such as a touch screen display which is capable of providing outputs to a user as well as receiving inputs.
The exemplary embodiment of the automated banking machine 10 also includes a receipt printer schematically indicated 30 . The receipt printer is operative to print receipts for users reflecting transactions conducted at the machine. Embodiments may also include other types of printing mechanisms such as statement printer mechanisms, ticket printing mechanisms, check printing mechanisms and other devices that operate to apply indicia to media in the course of performing transactions carried out with the machine.
Automated banking machine 10 further includes one or more processors schematically indicated 33 . Processor 33 , alternately referred to as a computer or a controller, is in operative connection with at least one memory or data store which is schematically indicated 34 . The processor 33 is operative to carry out programmed instructions to achieve operation of the machine in accomplishing transactions. The processor 33 is in operative connection with a plurality of the transaction function devices included in the machine.
The exemplary embodiment includes at least one communications device 36 . The communications device 36 may be one or more of a plurality of types of devices that enable the machine to communicate with other systems and devices for purposes of carrying out transactions. For example, communications device 36 may include a modem for communicating messages over a data line or wireless network, with one or more other computers that operate to transfer data representative of the transfer of funds in response to transactions conducted at the machine. Alternately the communications device 36 may include various types of network interfaces, line drivers or other devices suitable to enable communication between the machine 10 and other computers and systems. Exemplary embodiments may include features like those disclosed in U.S. Pat. No. 7,266,526 the disclosure of which is incorporated herein by reference in its entirety.
Machine 10 further includes a safe or chest 40 enclosing a secure area 42 . Secure area 42 is used in the exemplary embodiment to house critical components and valuable documents. Specifically in the exemplary embodiment secure area 42 is used for housing currency, currency dispensers, currency stackers, and other banking machine components. For purposes of this disclosure a cash dispenser or a currency dispenser shall include any mechanism that makes currency stored within the machine accessible from outside the machine. Cash dispensers may include features of the type disclosed in U.S. Pat. Nos. 7,261,236; 7,240,829; 7,114,006; 7,140,607 and 6,945,526 the disclosures of each of which are incorporated herein by reference in their entirety. Chest 40 includes a chest housing 44 including a top wall 46 having an upper surface 48 outside of the secure area 42 . Top housing 12 is supported on the chest 40 such that the secure area 42 is generally below the interior area 20 .
Chest 40 also includes a chest door 50 that is moveably mounted in supporting connection with the housing. Chest door 50 , shown in the closed position in FIG. 4 and in an open condition in FIG. 5 , is generally closed to secure the contents of the chest 40 . In this exemplary embodiment, the chest door 50 is used to close a first opening 52 at a first end 54 of the chest housing 44 . In other embodiments the chest opening and door may have other configurations. In the exemplary embodiment, chest door 50 includes a first device opening 56 therethrough and cooperates with mechanisms inside and outside the chest for passing currency or other items between a customer and devices located inside the chest 40 .
Referring again to FIG. 3 , machine 10 also includes a plurality of sensing devices for sensing various conditions in the machine. These various sensing devices are represented schematically by component 58 for simplicity and to facilitate understanding. It should be understood that a plurality of sensing devices is provided in the machine for sensing and indicating to the processor 33 the status of devices within the machine.
Exemplary automated banking machine 10 further includes a plurality of actuators schematically indicated 60 and 62 . The actuators may comprise a plurality of devices such as motors, solenoids, cylinders, rotary actuators and other types of devices that are operated responsive to the processor 33 . It should be understood that numerous components within the automated banking machine are operated by actuators positioned in operative connection therewith. Actuators 60 and 62 are shown to schematically represent such actuators in the machine and to facilitate understanding.
Machine 10 further comprises at least one currency dispenser mechanism 64 housed in secure area 42 . The currency dispensing mechanism 64 is operative responsive to the processor 33 to pick currency sheets from a stack of sheets 66 housed in one or more canisters 68 . The picked currency sheets may be arranged by a currency stacker mechanism 70 for presentation through a delivery mechanism 74 which operates to present a stack of note or other documents to a customer.
When chest door 50 is in the closed position, at least an end portion of a sheet delivery mechanism 74 extends through first opening 56 in the chest door 50 . In response to operation of the processor 33 , when a desired number of currency sheets have been collected in a stack, the stack is moved through delivery mechanism 74 .
As the sheets are moved through delivery mechanism 74 toward the first opening 56 , the controller 32 operates a suitable actuating device to operate a gate 78 so as to enable the stack of sheets to pass outward through the opening. As a result the user is enabled to receive the sheets from the machine. After a user is sensed as having removed the stack from the opening, the controller may operate to close the gate 78 so as to minimize the risk of tampering with the machine.
With reference to FIG. 2 , in this exemplary embodiment, machine 10 further includes a rollout tray 80 . Rollout tray 80 is moveably mounted in supporting connection with slides 84 . The slides 84 enable movement of the rollout tray 80 between the extended position shown in FIG. 2 and a retracted position within the interior area 20 of the top housing 12 . Rollout tray 80 in the exemplary embodiment may be similar to that shown in U.S. Pat. No. 6,082,616, the disclosure of which is incorporated by reference as if fully rewritten herein.
Rollout tray 80 may have several upper banking machine components supported thereon including card reader 24 , input keys 26 , display 28 , receipt printer 30 , and other components as appropriate for the particular machine 10 .
This exemplary embodiment further includes an upper fascia 86 in supporting connection with rollout tray 80 . The upper fascia 86 may include user interface openings such as a card opening 88 through which a customer operating the machine 10 may insert a credit, debit or other card, or a receipt delivery slot 90 through which printed transactions receipts may be delivered to the customer. Rollout tray 80 moveably supports upper fascia 86 relative to the top housing 12 so that upper fascia 86 is movable between a first position covering the front opening and a second position in which the upper fascia is disposed from the front opening 22 .
As illustrated in FIG. 1 , in the operative condition of machine 10 , the rollout tray 80 is retracted into the interior area 20 of the housing 12 . Upper fascia 86 operates to close front opening 22 and provide an attractive appearance for machine 10 , while allowing a customer to input information and receive outputs from machine 10 .
With reference to FIG. 6 , in this exemplary embodiment, the forward-most parts of side walls 14 and 16 and top wall 18 of housing 12 define a forward region 94 , shown in dashed lines, bounding the front opening 22 . In this exemplary embodiment, upper fascia 86 includes a rearwardly extending portion 98 , also shown in dashed lines. Rearwardly extending portion 98 is dimensioned to overlie in generally surrounding relation, the forward region 94 when rollout tray 80 is retracted and upper fascia 86 is in the first position. In some embodiments the rearwardly extending portion may be contoured or tapered so as to extend further inwardly with increasing proximity to the front of the fascia. Such tapered control may engage and help to close and/or align the fascia and the top housing 12 .
With reference to FIG. 7 , when machine 10 is viewed from the rear, there may be a first gap 100 separating the rearwardly extending portion 98 of upper fascia 86 from the top housing 12 . In some embodiments it may be desirable that first gap 100 be minimal to prevent unauthorized access to interior area 20 . First gap 100 in the exemplary embodiment is not visible when machine 10 is viewed from the front.
In this exemplary embodiment, the upper fascia 86 is formed of a plastic material and the top housing 12 is formed of sheet metal. Alternately, the extending portion 98 or forward portion 94 shown in FIG. 6 , or both, may include resilient materials to provide for engagement and sealing of the housing and the fascia in the closed position. However, other materials may be chosen, and these approaches are exemplary.
With reference to FIGS. 1 , 4 and 5 , the exemplary embodiment further includes a lower fascia 110 moveably mounted on the chest housing 44 . In this exemplary embodiment, lower fascia 110 is operable to move between a covering position as illustrated in FIG. 1 , and an accessible position as illustrated in FIGS. 4-5 . In other applications, it may be preferable to provide a selectively removable lower fascia, or other approaches to supporting the lower fascia on the chest portion.
The exemplary lower fascia 110 operates to cover the chest 40 to thereby provide a more attractive appearance to machine 10 . In the exemplary embodiment, lower fascia 110 includes a front face 112 and first and second side extensions 114 , 116 , respectively.
In the exemplary embodiment, illustrated in FIGS. 5 and 7 , chest housing 44 includes first and second side walls 120 , 122 , respectively. First side wall 120 includes a forward portion 124 and second side wall includes a forward portion 126 (shown in phantom in FIG. 7 ). When the chest door 50 is in the closed position and the lower fascia 110 is in the covering position, the first and second side extensions 114 , 116 , respectively, overlie forward portions 124 , 126 .
Thus, when machine 10 is viewed from the front (see FIG. 1 ), the lower fascia 110 covers the chest 40 from side to side. When machine 10 is viewed from the rear (see FIG. 7 ), a lower gap (not shown) between the first side extension 114 and the first side wall 120 of the chest housing 44 and a lower gap 130 between the second side extension and 116 the second side wall 122 may be visible, although such lower gaps are not viewable from the front of machine 10 . In some applications, it may be desirable to minimize the lower gaps 130 .
As best illustrated in FIG. 8 , in the exemplary embodiment, the rearwardly extending portion 98 of upper fascia 86 includes a rearward facing end edge 134 . Also, in the exemplary embodiment, first side extension 114 of lower fascia 110 includes rearward facing end edge 138 . When viewed from the first side of machine 10 , in the exemplary embodiment, end edge 134 of upper fascia 86 and end edge 138 of lower fascia 110 are substantially vertically aligned along a first side of machine 10 when the upper fascia 86 is in the first position and the lower fascia 110 is in the covering position.
With continued reference to FIG. 8 , in the exemplary embodiment, upper fascia 86 is bounded by a lower surface 140 . Lower fascia 110 is bounded by an upper surface 142 . In the exemplary embodiment, lower surface 140 is adapted for substantial parallel horizontal alignment with upper surface 142 when the upper fascia 86 is in the first position and the lower fascia 110 is in the covering position. The alignment of the fascia surfaces presents an attractive appearance to machine 10 .
In this exemplary embodiment, the rearwardly extending portion 98 further operates to simplify the manufacture and assembly of the machine 10 . In some previous machines, it was necessary to more precisely control the alignment of the walls of the upper fascia 86 with the perimeter of the front opening. However, in this disclosed exemplary embodiment, because the rearwardly extending portion 98 overlies the forward region 94 , the required precision is lessened. Further, in those embodiments which include a tapered engagement, alignment of the top housing 12 and upper fascia 86 is facilitated.
With particular reference to FIG. 5 , lower fascia 110 may include an access opening 118 therein. In this exemplary embodiment, access opening 118 in the lower fascia 110 is adapted to be substantially aligned with first device opening 56 in chest door 50 when chest door is closed and lower fascia 110 is in the covering position. In this exemplary embodiment, when the chest door 50 is closed and lower fascia 110 is in the covering position, at least an end portion of sheet delivery mechanism 74 extends in the first device opening 56 in chest door 50 and access opening 118 in lower fascia 110 .
As illustrated in FIGS. 1 and 2 , in this exemplary embodiment, machine 10 includes a first locking mechanism 146 for selectively retaining the rollout tray 80 in the retracted position when upper fascia 86 covers the front opening 22 . The first locking mechanism may be of the type described in U.S. Pat. No. 6,082,616 the disclosure of which is incorporated herein by reference in its entirety.
In the exemplary embodiment, machine 10 also includes a second locking mechanism 148 for selectively securing lower fascia 110 in the covering position.
With particular reference to FIGS. 4 , 5 and 9 , in another exemplary embodiment machine 10 may include a top housing 12 as previously described. Machine 10 further includes chest 40 having chest door 50 mounted to the housing 44 by one or more chest door hinge assemblies 152 . Lower fascia 110 is moveably mounted to chest housing 44 by one or more fascia hinges 154 . In this exemplary embodiment, fascia hinge 154 and chest door hinge assembly 152 are situated on the same side of the chest housing 44 so that lower fascia 110 and chest door 50 pivot generally in the same direction relative to the chest.
From time to time, the banking machine components enclosed within secure enclosure 42 must be accessed for replenishment or other servicing activity. Thus, lower fascia 110 may be selectively moved from a covering position into an accessible position to allow access to chest door 50 . Chest door 50 may then be selectively opened.
In this exemplary embodiment, as best seen in FIG. 9 , lower fascia 110 is operable to engage the open chest door 50 to prevent its movement back to a closed position. In this exemplary embodiment, lower fascia 110 includes an inwardly directed flange 156 carried on an inner surface at a side opposite the fascia hinge 154 . Inwardly directed flange 156 is dimensioned to engage at least a portion of chest door 50 when the lower fascia 110 is in the accessible position and the chest door 50 is in the open position. In the exemplary embodiment, lower fascia 110 is adapted to pivot away from the chest door 50 to at least an extent where the chest door may be disengaged from inwardly directed flange 156 . Exemplary embodiments may include features of the type discussed in U.S. Pat. Nos. 7,159,767; 7,152,784; 7,000,830; and 6,871,602 the disclosures of each of which are incorporated herein by reference in their entirety.
An exemplary embodiment includes a method for accessing the contents of the secure area for servicing components housed therein or to replenish currency sheets. The method includes placing the lower fascia into an accessible position from a covering position to uncover the chest door; opening the chest door to provide access to the secure area through an opening in the chest housing; and engaging the chest door and the lower fascia to hold the chest door in an open condition. Thus a currency dispenser mechanism or other components may be accessed. Servicing the currency dispenser may include adding or removing currency sheets from operative engagement with the currency dispenser mechanism.
The method may further include engaging the chest door with an inwardly directed flange that is mounted in supporting connection with the lower fascia.
To return the machine to an operational condition, the method includes moving the lower fascia outwardly relative to the engaged chest door to disengage the chest door; closing the chest door; and repositioning the lower fascia into the covering position.
Repositioning the lower fascia into the covering position includes overlying a first forward portion of the chest housing with a first side extension of the lower fascia and overlying a second forward portion of the chest housing with a second side extension of the lower fascia.
Prior to placing the lower fascia into the accessible position, the method includes unlocking a first locking mechanism operable to selectively retain the lower fascia in a covering position.
Some machines may be equipped with another exemplary embodiment of a chest or safe 160 , as best seen in FIGS. 10-11 . Chest 160 includes a chest housing 162 having a first end 164 defining a first opening 166 therein and a second end 168 defining a second opening 170 therein. The chest of this exemplary embodiment is particularly adapted for applications wherein a common chest housing can be utilized in either “front-load” machines or “rear-load” machines. By “front-load” machine it is meant that access to a secure area 174 in an operable machine may be selectively attained from the front of the machine, which is the same side that customers use to provide input to the machine. By “rear-load” machine it is meant that access to the secure area 174 in an operable machine may be selectively attained from the rear of the machine, while customer inputs are provided at the front of the machine.
In this exemplary embodiment, chest 160 includes a first chest door 178 moveably mounted adjacent a first end 164 of chest housing 162 to selectively close the first opening 166 . Chest 160 further includes a second chest door 180 moveably mounted adjacent the second end 168 to selectively close the second opening 170 .
In the exemplary embodiment illustrated in FIG. 10 , chest 160 is adapted for use in a front load machine wherein under usual operating conditions, first chest door 178 is selectively movable to open or close first opening 166 to allow access to secure area 174 . In this exemplary embodiment, second chest door 180 is adapted to remain closed during usual operation of the machine, including those times when access to secure area 174 is desired. For purposes of this disclosure, the term “semi-permanently” closed is used to describe a condition of a chest door that closes an opening in the chest housing in a manner that does not readily permit access to the secure area. In this way, a “semi-permanently” closed chest door is not used as the primary means for accessing the chest interior. However, under appropriate conditions the semi-permanently closed chest door can be opened.
In this exemplary embodiment, first chest door 178 is the operable door and second chest door 180 is adapted to be semi-permanently closed. In other embodiments, for instance in rear-load machines, it may be desirable to utilize chest 160 as illustrated in FIG. 11 where the second chest door 180 is the operable door while first chest door 178 is adapted to be semi-permanently closed.
With particular reference to FIGS. 10 and 12 , in the exemplary embodiment, the first chest door 178 is equipped with a suitable locking bolt mechanism generally denoted 186 . Locking bolt mechanism 186 is operative to selectively enable securing first chest door 178 in a locked condition. Locking bolt mechanism 186 may be of the type described in U.S. Pat. No. 6,089,168 which is incorporated by reference in its entirety as if fully rewritten herein. Of course, other suitable bolt works can be utilized to accomplish the objectives.
Locking bolt mechanism 186 of the exemplary embodiment includes a locking bolt 188 which includes a plurality of locking bolt projections 190 . Locking bolt 188 is mounted in operatively supported connection with an interior surface of first chest door 178 so as to be slideably movable between an extended position and a retracted position.
First chest door 178 also has a lock 192 mounted thereto. Lock 192 cooperates with locking bolt mechanism 186 so that first chest door 178 is enabled to be changed from a locked condition to an unlocked condition. As shown in FIG. 10 , the chest housing 162 includes a plurality of vertically spaced locking bolt apertures 194 which are sized and positioned for accepting the locking bolt projections 190 .
It will be appreciated by those skilled in the art that the locking bolt mechanism because it provides multiple places for engagement with the chest housing, achieves more secure locking of the door in the closed position than a locking bolt mechanism providing a single place for engagement with the chest housing.
In the exemplary embodiment, first chest door 178 includes a plurality of dead bolt projections 196 extending on a hinge side of the door. These dead bolt projections 196 are preferably positioned and sized to be accepted in the dead bolt apertures 198 in housing 162 . As will be appreciated, the acceptance of the dead bolt projections 196 into the dead bolt apertures 198 provides enhanced security. In an exemplary embodiment, the dead bolt apertures and the locking bolt apertures are covered by trim pieces 200 (shown in FIG. 9 ) that extend on the outside of the housing.
With reference to FIG. 10 , in the exemplary embodiment, the first chest door 178 is operably connected to the chest housing via one or more first chest hinge assemblies 202 . The exemplary chest hinge assembly 202 may be of the type described in U.S. Pat. No. 6,089,168 and/or 7,156,297, the disclosures of which are incorporated herein in their entirety. It will be readily understood that other hinge constructions may be used in other embodiments.
In the exemplary embodiment, the second chest door 180 may be secured in a closed position by a securing mechanism that generally minors the locking bolt mechanism 186 and lock 192 . Alternately, as illustrated in FIG. 10 , second chest door 180 may be “semi-permanently” secured by an alternate securing mechanism 204 . The alternate securing mechanism 204 may include a bolt member 206 or other mechanism that is less complex than the locking bolt mechanism and lock previously described. In this exemplary embodiment, routine access to the secure area 174 via second chest door 180 is not necessary during normal operation of the machine. Thus, the alternate securing mechanism 204 is operable to “semi-permanently” engage the chest door 180 . This may be done, for example, by securing the bolt with fasteners or other devices that are only accessible from within the interior of the chest portion. Of course, in some alternative embodiments both chest doors may be equipped with operational locking bolt mechanisms and locks.
The manufacture of an exemplary machine may be simplified by use of chest 160 . A common chest housing may be utilized in applications requiring a front-load machine or a rear-load machine. After the housing has been assembled, the positioning of a locking bolt mechanism may be chosen according to the configuration of the chest. Additionally, at a subsequent time, the operational features may be changed so that the initial operational chest door becomes the non-operational door and vice versa. Thus, the manufacturing process is simplified by the versatility of the chest housing.
Of course it will be readily appreciated that machines incorporating this exemplary embodiment of chest 160 may include any of the other features described elsewhere.
An exemplary embodiment includes a method for utilizing a machine that is equipped with a chest having two opposed openings. The chest housing includes a first opening at a first end thereof and a second opening at a second opposed end. The first door is moveably mounted in supporting connection with the chest housing so that the first chest door is operative to selectively close the first opening. A second chest door is moveably mounted in supporting connection with the chest housing so that the second door is operative to semi-permanently close the second opening. At least one lower banking machine component is mounted in supporting connection with the chest housing in the secure area.
In the exemplary method, a first locking bolt mechanism in supporting connection with the first chest door is operated to selectively securely engage the first chest door with the chest housing. A first securing mechanism in supporting connection with the second chest door is operated to semi-permanently securely engage the second chest door with the chest housing.
The method includes accessing at least one lower banking machine component of an machine through a first opening in a chest housing bounding a secure area; and preventing access to the at least one lower banking machine component through the second opening.
The method further includes replacing the first locking bolt mechanism with a second securing mechanism in supporting connection with the first chest door, wherein the second securing mechanism is operative to semi-permanently securely engage the first chest door with the chest housing; and replacing the first securing mechanism with a second locking bolt mechanism in supporting connection with the second chest door, wherein the second locking bolt mechanism is operative to selectively securely engage the second chest door with the chest housing. Thus, the door chosen as the operative door can be selected and changed.
The exemplary machine may include a lower fascia that is mounted in supporting connection with the chest housing, wherein the lower fascia is selectively movable between a covering position and an accessible position. The exemplary method may include moving the lower fascia from the covering position to the accessible position prior to accessing the lower banking machine component. Further, the method may include engaging the first chest door with the lower fascia to hold the first door in the open condition.
The at least one lower banking machine component may comprise a currency dispenser mechanism. The exemplary method includes servicing the currency dispenser mechanism after the at least one lower banking machine component is accessed. This may include for example features included in U.S. Pat. Nos. 7,195,237 and/or 7,111,776 the disclosures of each of which are incorporated herein by reference in their entirety.
The at least one lower banking machine component may comprise a currency stacker. The exemplary method includes servicing the currency stacker.
Yet another exemplary embodiment of a machine 210 is illustrated in FIGS. 13-15 . Machine 210 includes a top housing cover 212 including first and second side walls 214 , 216 , top wall 218 , and rear wall 219 . Top housing cover 212 defines a front opening 222 and a bottom opening 224 . In a first (operable) position, top housing cover 212 covers an interior area in which various upper banking machine components such as a display, a receipt printer, a card reader, input keys, a controller, communication device, and others may be disposed.
In this exemplary embodiment, machine 210 further includes a chest 240 bounding a secure area in a manner similar to that previously described. Chest 240 includes a housing 244 having a top wall 248 . Top housing cover 212 is adapted for rearward slidable movement relative to top wall 248 to a second position for service.
In this exemplary embodiment, a first upwardly extending flange member 254 is mounted in supporting connection with top wall 248 along a first side thereof. A second upwardly extending flange member 256 (not shown in this view) is mounted in supporting connection with top wall 248 along a second side thereof.
Supported on the first side wall 214 of top housing cover 212 is a first cooperating channel member 260 having a pair of spaced downwardly extending projections 262 defining a first channel 264 therebetween Likewise, on the second side wall 216 of top housing cover 212 there is supported a second cooperating channel member 268 having a pair of spaced downwardly extending projections 270 defining a second channel 272 therebetween.
Top housing cover 212 is adapted for slidable movement relative to the top wall 248 by the slidable engagement of the first flange member 254 within first channel 264 and the slidable engagement of the second flange member 256 within second channel 272 .
In this exemplary embodiment, machine 210 includes an upper fascia 276 operable to selectively cover the front opening 222 . The top housing cover 212 is adapted for rearward movement relative to the top wall 248 in the direction of arrow A such that rearward displacement of the top housing cover 212 allows access to the upper banking machine components in the interior area, for example, for servicing.
It is contemplated that in exemplary embodiments the positioning of the flange members 254 , 256 and the channels 264 , 272 be reversed. For example, the top housing cover 212 may support flange members and the mounting tray may support cooperating channel members to accomplish a similar slidable relationship therebetween.
FIG. 14 illustrates an exemplary embodiment wherein the flange members 254 , 256 are incorporated into a mounting tray 274 which is operable to receive and support one or more upper banking machine components, which for ease of illustration are not shown in this view. This embodiment allows for ease of assembly of the exemplary machine 210 . The applicable upper banking machine components can be readily mounted onto mounting tray 274 , which is mounted in supporting connection with top wall 248 of chest housing 244 . Top housing cover 212 may thereafter be positioned by slidable movement of flange members 254 , 256 in respective channels 264 , 272 .
In an alternate exemplary embodiment, illustrated in FIG. 15 , machine 210 may include a rollout tray 275 similar to rollout tray 80 as previously described. Flange members 254 , 256 may be mounted in supporting connection with rollout tray 275 . Thus, upper banking machine components may be accessed by rearwardly sliding the top housing cover 212 , extending the rollout tray 275 , or a combination of both.
Machine 210 may further include at least one removable fastener 280 for selectively engaging the top housing cover 212 with at least one flange member 254 , 256 to prevent relative slidable movement therebetween. In the exemplary embodiment, first and second fasteners 280 are used to secure the top housing cover 212 .
Machine 210 may further include a first locking mechanism 282 to secure the top housing cover to upper fascia 276 . In this exemplary embodiment, the locking mechanism is operable in response to a key 284 . In the exemplary embodiment illustrated in FIG. 15 it is contemplated that fasteners 280 are covered by a rearwardly extending portion of upper fascia similar to portion 98 shown in FIG. 6 . Thus, fasteners 280 are not accessible from outside the machine until first locking mechanism 282 has been operated to release upper fascia 276 so that the upper fascia 276 can be moved away from top housing cover 212 .
In the exemplary embodiment, machine 210 may include a lower fascia 288 with features similar to a lower fascia previously described. Lower fascia 288 may be secured in the covering position by a second locking mechanism 290 .
This exemplary embodiment provides ready access to the upper banking machine components, for example, for servicing or replacing. To access the upper banking machine components, fasteners 280 are removed. It is contemplated that in an exemplary embodiment, the fasteners may not be accessible until after the first locking mechanism 282 is unlocked and the upper fascia is displaced slightly to uncover fasteners 280 . In other embodiments, the fasteners may be directly accessed.
The top housing cover 212 may then be moved rearwardly, away from upper fascia 276 so that the interior area is accessible. During servicing, the top housing cover 212 may be selectively positioned so that some portion or none of the upwardly extending flanges 254 , 256 remain engaged with the channel members 260 , 268 , respectively.
In one exemplary embodiment, a method is provided for accessing banking machine components. The exemplary method includes supporting the top housing cover in a slidable relationship with the top wall of the chest housing, wherein the top housing cover includes a front opening; selectively rearwardly sliding the top housing cover away from a first position in which an upper fascia covers the front opening; and accessing at least one upper banking machine component that is mounted in supporting connection with the top wall of the chest housing.
The exemplary method further includes removing fasteners that may be used to selectively secure the top housing cover in the first position.
The exemplary method further includes operating a locking mechanism to release the top housing cover and the upper fascia.
The exemplary method further includes accessing an upper banking machine component for servicing. The at least one upper banking machine component may be a display that is accessed for servicing.
In one embodiment the machine includes side flange members mounted in supporting connection with a top wall of a chest housing and cooperative channel members mounted in supporting connection with the top housing cover. In this exemplary embodiment, the method further includes slideably engaging a first flange member with a first channel of a first channel member.
In another exemplary embodiment, illustrated in FIGS. 16 and 17 , machine 310 may include a chest 312 having a chest housing 314 including top wall 316 . As in previously described embodiments, chest housing 314 bounds a secure area which holds lower banking machine components including a currency dispenser mechanism which may be similar to mechanism 64 shown in FIG. 3 . Machine 310 further includes a top housing 320 (shown in phantom) bounding an interior area 322 .
In this exemplary embodiment, machine 310 includes a processor case 324 that houses the primary machine processor or processors. The processor may be an Intel Pentium or Celeron processor. Of course, in some embodiments the case may house multiple processors or no processors at all. The processor causes operation of the various devices and mechanisms in the machine.
In this exemplary embodiment, processor case 324 is in supporting connection with top wall 316 of chest housing 314 . Processor case 324 includes a first functional side 326 that is operable to establish connections, such as through cable 327 , from the various banking machine components. Other processor components, including but not limited to circuit cards having various functions, additional processors, drives (CD, DVD, floppy), power supplies, memory, or encryption cards, may be carried on or within processor case 324 . Such components may also be accessed, removed and/or replaced and routine maintenance performed through access to the functional side of the processor case.
In order to minimize the space occupied by machine 310 , it is advantageous to orient processor case 324 of the exemplary embodiment so that the first functional side 326 is substantially parallel to a first side wall 328 (shown in phantom) of top housing 320 . However, in order to easily access first functional side 326 for servicing or connecting cables, it is advantageous to orient processor case 324 so that the first functional side 326 is substantially perpendicular to the first side wall 328 , facing the front opening of the machine. In order to accomplish both these purposes, the processor case 324 of the exemplary embodiment is rotationally supported in connection with the top wall 316 of the chest housing 314 . The processor case 324 is selectively rotationally movable between an operational position, shown in FIG. 17 , wherein the first functional side 326 is substantially parallel to the first side wall 328 , and a service position, shown in FIG. 16 , wherein the first functional side 326 is substantially perpendicular to the first side wall 328 .
In this exemplary embodiment, a rollout tray 330 is supported on the top wall 316 of the chest housing 314 . As in earlier described exemplary embodiments, the rollout tray 330 is selectively movable between a retracted position wherein the rollout tray 330 is within the interior area 322 , and an extended position wherein the rollout tray 330 extends outwardly from the interior area through a front opening in the top housing 320 . In the exemplary embodiment, various upper banking machine components such as display 332 , receipt printer 334 , and card reader 336 are supported on rollout tray 330 . Also, an upper fascia 340 may be mounted in supporting connection with rollout tray 330 . As in other described embodiments, when the rollout tray is in the retracted position, the upper fascia 340 covers the front opening in the top housing.
In the exemplary embodiment, when rollout tray 330 is in the retracted position, as illustrated in FIG. 16 , the processor case 324 is prevented from rotating from the operational position to the service position. When the rollout tray 330 is in the extended position, as illustrated in FIG. 17 , there is enough clearance in the interior area 322 to permit the processor case 324 to be rotated into the service position. Thus, when the rollout tray 330 is in the extended position, the upper banking machine components supported thereon are readily accessible for service. Likewise, the cable connections and any processor components carried on the processor case are accessible for service.
In a method for servicing banking machine components of a machine, a rollout tray 80 mounted in supporting connection with a top housing 320 is extended from a retracted position so that the rollout tray extends through a front opening in the top housing 320 . The method includes disengaging any locking mechanisms that operate to retain the rollout tray 80 in the retracted position.
A processor case 324 disposed in an interior area 322 bounded by the top housing 320 may be rotated from an operational position to a service position. At least one processor component mounted in supporting connection with the processor case 324 may be accessed for servicing. After servicing of the processor component is complete, the processor case 324 may be rotationally returned to the operational position from the service position. Thereafter, the rollout tray 80 may be repositioned into the retracted position.
The step of servicing the processor component may include connecting or disconnecting cables or connections, adding or replacing components such as circuit cards, performing diagnostic tests and other functions to facilitate operation of the machine.
Prior to repositioning the rollout tray 80 , other banking machine components may be serviced while the rollout tray is extended. For example, a display, card reader, and receipt printer assembly are readily accessible for service. The service can include routine maintenance, replacement of non-working components, addition of other banking machine components, and the like. Connections with the processor can be readily made while the rollout tray is in the extended position and the processor case is in the service position.
The machine may include a slidable top housing cover 212 as earlier described. The service method includes the step of rearwardly sliding the top housing cover 212 . After the servicing of banking machine components is completed, the method includes returning the top housing cover 212 to an operational position.
During servicing of the machine, the lower banking machine components may also be accessed for servicing. The service method includes disengaging any locking mechanisms that retain the lower fascia in a covering position. The lower fascia may thereafter be moved into the accessible position. The locking bolt mechanism that securely engages the chest door with the chest housing may be disengaged so that the chest door may be placed in the open position.
An exemplary method further includes the step of engaging the chest door with the lower fascia when the chest door is in the open position and the lower fascia is in the accessible position in order to retain the door in the open position.
The lower banking machine components, such as currency stacker, currency dispenser mechanism, and currency delivery mechanism (as shown in FIG. 3 ). An exemplary service method includes performing routine maintenance, replenishing currency, removing sheets, disengaging sheets from the currency dispenser mechanism, replacing components and the like.
The machine can include connections and/or cables that extend between the processor case and lower banking machine components that are generally housed within the secure chest. The chest housing may include various openings 350 through the walls to accommodate the connections and/or cables ( FIGS. 10-11 and 17 ). When the processor case is in the service position, the connections can be readily established, maintained and/or changed.
An exemplary method of constructing a machine apparatus is described. The exemplary method includes mounting a top housing in supporting connection with a chest adapted for use in an automated banking machine apparatus. A first chest door is operable to selectively close a first opening in the chest housing.
The method further includes mounting an upper fascia in supporting connection with the top housing and mounting a lower fascia in movable supporting connection with the chest housing.
The upper fascia and the top housing are selectively positioned relative each other so that a front opening in the top housing is selectively covered by the upper fascia, and wherein a rearwardly extending portion of the upper fascia overlies a forward region of the top housing.
The lower fascia is selectively positioned in a covering position relative a chest door wherein a first side extension of the lower fascia overlies a first forward portion of the chest housing and wherein a second side extension of the lower fascia overlies a second forward portion of the chest housing.
In an exemplary method, a lower edge surface of the upper fascia is placed in substantially parallel alignment with an upper edge surface of the lower fascia and an end edge of a rearwardly extending portion of the upper fascia is substantially vertically aligned with an end edge of a first side extension of the lower fascia at a first side of the machine.
In an exemplary method, a second chest door is moveably mounted in supporting connection with the chest housing to operably close a second opening in the chest housing. A first locking bolt mechanism may be mounted to the first chest door and an alternate securing mechanism may be mounted to the second chest door.
In an exemplary method, a processor case is mounted in supporting rotational connection with a top wall of the chest housing wherein the processor case is selectively movable between an operational position and a service position, and wherein the processor case houses at least one processor.
In an exemplary method, at least one upper banking machine component is mounted in supporting connection with a rollout tray which is mounted in movable supporting connection with the chest housing, wherein the rollout tray is selectively movable between a retracted position wherein the rollout tray is within an interior area, and an extended position wherein the rollout tray extends outwardly from the interior area through the front opening in the top housing.
The exemplary method includes selectively placing the rollout tray in the extended position, selectively rotating the processor case into the service position, and establishing an operable connection between the at least one upper banking machine component and the at least one processor.
In an exemplary method, the lower fascia is equipped with an inwardly extending flange operative to selectively engage the chest door when the lower fascia is in the accessible position and the chest door is in the open position.
With reference to FIG. 18 , in this exemplary embodiment there is shown therein an automated banking machine, generally indicated as 410 . In this exemplary embodiment, the automated banking machine 410 is an automated teller machine. The machine 410 includes a housing 412 mounted atop a chest 440 . The housing 412 includes a first side wall 414 , a second side wall 416 ( FIG. 19 ), a rear wall or panel 419 , and a top wall 418 , and defines a front opening 422 . A fascia 486 is adapted to cover the front opening 422 of the housing 412 and may be secured to the housing 412 with a lock 448 . The fascia 486 is in operatively supported connection with the housing 412 and is operatively supported by the housing 412 through two horizontally disposed members 483 , 484 . As will be appreciated by those skilled in the art, the fascia 486 may additionally or alternatively be secured to the chest 440 . In an exemplary embodiment, the two horizontally disposed members 483 , 484 are slideable members adapted to enable the fascia 486 to be moved away from the front opening 422 of the housing 412 . Further, the fascia 486 , when moved away from the front opening 422 , cooperates with the housing 412 and the two horizontally disposed members 483 , 484 to define a space which may be at least partially occupied by a servicer 402 while servicing the machine 410 . Various serviceable components, generally identified in FIG. 18 as components 450 - 455 , may be supported by the fascia 486 , the housing 412 , the chest 440 , or combinations thereof.
With reference to FIG. 19 , there is shown a further view of the exemplary embodiment of the machine 410 described under FIG. 18 . Shown is the servicer 402 at least partially occupying the space defined by the fascia 486 , the housing 412 , and the two horizontally disposed members 483 , 484 .
With reference to FIG. 20 , in this exemplary embodiment there is shown therein an automated banking machine, generally indicated as 510 . The machine 510 includes a housing 512 mounted atop a chest 540 . The housing 512 includes a first side wall 514 (not shown), a second side wall 516 , and a top wall 518 , and defines a rear opening 524 . A rear panel 519 is adapted to cover the rear opening 524 of the housing 512 and may be secured to the housing 512 with a lock 549 . The rear panel 519 is in operatively supported connection with the housing 512 and is operatively supported by the housing 512 through two-horizontally disposed members 585 , 587 . In an exemplary embodiment, the two horizontally disposed members 585 , 587 are slideable members adapted to enable the rear panel 519 to be moved away from the rear opening 524 of the housing 512 . Further, the rear panel 519 , when moved away from the rear opening 524 , cooperates with the housing 512 and the two horizontally disposed members 585 , 587 to define a space which may be at least partially occupied by the servicer 402 while servicing the machine 510 . Various serviceable components, generally identified in FIG. 20 as components 558 - 563 , may be supported by the rear panel 519 , the housing 512 , the chest 540 , or combinations thereof.
With reference to FIG. 21 , in this exemplary embodiment there is shown therein an automated banking machine, generally indicated as 610 . The machine 610 includes a housing 612 mounted atop a chest (not shown). The housing 612 includes a first side wall 614 , a second side wall 616 , a rear wall 619 , and a top wall 618 , and defines a front opening 622 . A fascia 686 is adapted to cover the front opening 622 of the housing 612 and may be secured to the housing 612 with a lock (not shown). The fascia 686 is in operatively supported connection with the housing 612 and is operatively supported by the housing 612 through two horizontally disposed members 683 , 684 . In an exemplary embodiment, the two horizontally disposed members 683 , 684 are slideable members adapted to enable the fascia 686 to be moved away from the front opening 622 of the housing 612 . Further, the fascia 686 , when moved away from the front opening, 622 , cooperates with the housing 612 and the two horizontally disposed members 683 , 684 to define a space which may be at least partially occupied by the servicer 402 while servicing the machine 610 . Various serviceable components, generally identified in FIG. 21 as components 664 - 669 , may be supported by the fascia 686 , the housing 612 , the chest (not shown), or combinations thereof.
Also shown in FIG. 21 , is an exemplary embodiment of a moveable component tray 690 . The moveable component tray 690 may support one or more components, generally 664 - 666 . The tray 690 is in operatively supported connection with the housing 612 and is operatively supported by the housing 612 through two horizontally disposed members 692 , 693 . In an exemplary embodiment, the two horizontally disposed members 692 , 693 are slideable members adapted to enable the one or more components, generally 664 - 669 , and their support tray 690 to be moved away from the housing 612 for servicing by the servicer 402 . Even when the support tray 690 is moved away from the housing 612 , the housing 612 , the tray 690 , one of the horizontally disposed members 684 , for example, and the fascia 686 cooperate to define a space which may be at least partially occupied by the servicer 402 . As will be appreciated by those skilled in the relevant art, the moveable tray 690 described herein and illustrated in FIG. 21 may also or additionally be included in a rear-access housing as illustrated in exemplary fashion in FIG. 20 . As will also be appreciated by those skilled in the art, the support tray 690 may be disposed in a vertical orientation.
With reference to FIG. 22 , in this exemplary embodiment there is shown therein an automated banking machine, generally indicated as 710 . The machine 710 includes a housing 712 mounted atop a chest (not shown). The housing 712 includes a first side wall 714 , a second side wall 716 , a rear wall 719 , and a top wall 718 , and defines a front opening 722 . A fascia 786 is adapted to cover the front opening 722 of the housing 712 and may be secured to the housing 712 with a lock (not shown). The fascia 786 is in operatively supported connection with the housing 712 and is operatively supported by the housing 712 through two horizontally disposed members 783 , 784 . In an exemplary embodiment, the two horizontally disposed members 783 , 784 are slideable members adapted to enable the fascia 786 to be moved away from the front opening 722 of the housing 712 . Further, the fascia 786 , when moved away from the front opening 722 , cooperates with the housing 712 and the two horizontally disposed members 783 , 784 to define a space which may be at least partially occupied by the servicer 402 while servicing the machine 710 . Various serviceable components, generally identified in FIG. 22 as components 770 - 775 , may be supported by the fascia 786 , the housing 712 , the chest (not shown), or combinations thereof.
Also shown in FIG. 22 , is an exemplary embodiment of a moveable component rack 790 . The moveable component rack 790 may support one or more serviceable components, generally 773 - 775 . The rack 790 is in operatively supported connection with the housing 712 and is operatively supported by the housing 712 through two horizontally disposed members 794 , 795 . In an exemplary embodiment, the two horizontally disposed members 794 , 795 are slideable members adapted to enable the one or more components, generally 773 - 775 , and their supporting rack 790 to be moved away from the housing 712 for servicing by the servicer 402 . Even when the supporting rack 790 is moved away from the housing 712 , the housing 712 , the rack 790 , one of the horizontally disposed members 784 , for example, and the fascia 786 cooperate to define a space which may be at least partially occupied by the servicer 402 . As will be appreciated by those skilled in the relevant art, the moveable rack 790 described herein and illustrated in FIG. 22 may also or additionally be included in a rear-access housing as illustrated in exemplary fashion in FIG. 20 . As will also be appreciated by those skilled in the art, the supporting rack 790 may be disposed in a vertical direction.
With reference to FIG. 23 , in this exemplary embodiment there is shown therein a portion of an automated banking machine, generally indicated as 810 . The machine 810 includes a housing 812 mounted atop a chest (not shown). The housing includes a first side wall (not shown), a second side wall 816 , a rear wall 819 , and a top wall 818 , and defines a front opening 822 . Also shown in FIG. 23 , is an exemplary embodiment of a pivotable component rack 890 . The pivotable component rack 890 is in operatively supported connection with the housing 812 and is operatively supported by the housing 812 through a pivot 896 . The pivotable component rack 890 may support one or more serviceable components, generally 876 . The pivot 896 is adapted to enable the one or more components, generally 876 , and their pivotable component rack 890 to be moved away from the housing 812 for servicing by the servicer 402 . As will be appreciated by those skilled in the art, the pivot 896 may alternatively be disposed in a vertical orientation.
An exemplary embodiment includes a method for accessing and servicing the contents, and particularly the serviceable components, of the housing to, but not limited to, clean, repair, or replace parts, make adjustments, replenish consumables such as paper, print materials, and lubricants, or exchange components. The method includes releasing the lock holding the cover adjacent to the opening of the housing of the automated banking machine and moving the cover away from the housing, wherein the cover remains in operatively supported connection with the housing, and wherein the cover is operatively supported by the housing through two horizontally disposed members. In an exemplary embodiment, the members are slideable horizontally disposed members and the method includes the step of sliding the cover away from the housing. The method further includes standing between the two horizontally disposed members and servicing at least one serviceable component of the automated banking machine. In a further exemplary embodiment, the method includes moving out from between the two horizontally disposed members, moving the cover back toward the housing, whereby the cover is positioned adjacent the housing opening, and securing the lock.
In a further exemplary embodiment, the method further includes moving the at least one component away from the housing for servicing. In a further exemplary embodiment, the step of moving the at least one component away from the housing includes sliding the at least one component away from the housing, pivoting at least a portion of the at least one component away from the housing, sliding a tray supporting the at least one component away from the housing, and sliding a rack supporting the at least one component away from the housing while standing between the two horizontally disposed members.
In a further exemplary embodiment, the method further includes moving the at least one component back into the housing after servicing. In a further exemplary embodiment, the step of moving the at least one component back into the housing includes sliding the at least one component back into the housing, pivoting the at least one portion of the at least one component back into the housing, sliding the tray supporting the at least one component back into the housing, and sliding the rack supporting the at least one component back into the housing while standing between the two horizontally disposed members.
As will be appreciated by those skilled in the art, the at least one component may alternatively be in operatively supported connection with the cover and the method include moving the at least one component moved away from the cover for servicing, servicing the at least one component, and subsequently moving the at least one component back to the cover. As will also be appreciated by those skilled in the art, the cover may comprise a fascia or a rear panel.
Exemplary embodiments may also include features described in U.S. Pat. Nos. 8,091,784; 8,090,663; 8,104,674; 8,104,676; 8,091,778; 8,100,323; 8,083,136; 8,070,055; 8,083,131; 8,079,512; 8,061,591; 8,052,049; 8,052,045; 8,052,044; 8,052,042; 8,061,593; 7,255,266; 7,251,626; 7,249,761; 7,246,082; 7,240,829; 7,240,827; 7,234,636; 7,229,009; 7,229,012; 7,229,008; 7,222,782; 7,216,801; 7,216,800; 7,216,083; 7,207,478; 7,204,411; 7,195,153; and 7,195,237 the disclosures of each of which are incorporated herein by reference in their entirety.
With reference to FIG. 24 , in this exemplary embodiment there is shown therein an automated banking machine, generally indicated as 910 . The machine 910 includes a housing 912 mounted atop a secure chest 940 . The chest 940 may be enclosed in a chest housing 944 or may itself comprise the exterior walls of a portion of the machine. The housing 912 bounds an interior area and includes a first sidewall 914 , a second sidewall 916 , and a top wall 918 . The walls define an opening 22 (shown in exemplary fashion in FIG. 2 ) to an interior area 20 (shown in exemplary fashion in FIG. 2 ). The housing 912 further includes housing vents 942 formed in the sidewalls 914 , 916 which provide ventilation and enable the movement of air into or out of the housing 912 . In the exemplary embodiment air is moved to help cool electronic parts contained, for example, in a component case 924 ( FIG. 25 ).
An upper fascia 986 provides an attractive appearance as well as security. The fascia 986 is in operatively supported connection with the housing 912 and moveable between a secure closed position adjacent to the housing opening 22 and a released away position. ( FIGS. 1 and 2 .) In the exemplary embodiment, a card reader 24 (shown in exemplary fashion in FIG. 3 ) is in operatively supported connection with the housing 912 and is operative to read indicia on user cards corresponding to financial accounts. Also in the exemplary embodiment, a display 928 and a cash dispenser 64 (shown in exemplary fashion in FIG. 3 ) are in operatively supported connection with the housing 912 . The component case 924 ( FIG. 25 ), which in the exemplary embodiment comprises a processor case, is in operatively supported connection with the housing 912 and may contain computer processors, circuit cards, memory devices and other electronic components (not shown). As shown in FIG. 26 , but best seen in FIG. 27 , the component case 924 further includes one or more component case vents 943 which may cooperate with one or more fans or other air movement devices (not shown) to help move air to and from the inside of the case and ventilate the interior of the component case 924 .
As will be understood from FIGS. 24 and 25 , ventilation air from the interior of the component case 924 may not easily reach or be drawn from outside the housing 912 which encloses the case 924 as well as other components of the machine 910 . As shown in exemplary fashion in FIG. 25 , a duct 930 is operatively disposed between the component case 924 at the component case vents 943 ( FIGS. 26 and 27 ) and the housing sidewall 916 at the at least one housing vent 942 ( FIGS. 24 and 25 ). Air from the interior of the component case 924 , by way of example only, warm air heated by the operation of processors or other components within the case 924 , may then be guided within the duct to outside the housing 912 . Likewise, in some embodiments and depending upon the direction of air flow, cooler air from outside the housing 912 may be guided to the interior of the component case 924 . In an exemplary embodiment, the duct 930 is adhered to the component case 924 with an adhesive 936 (shown in exemplary fashion in FIG. 30 ). In a further exemplary embodiment, the duct 930 may be alternatively and/or in addition adhered to the inside wall of the housing 912 . In a further exemplary embodiment, the adhesive 936 is releasable. In a further exemplary embodiment, the adhesive is resealable. Thus, the duct 930 may be released from its position and later resealed. This may be accomplished in exemplary embodiments by sealants which remain flexible and tacky at ambient temperatures.
A further exemplary embodiment is shown in FIGS. 27 and 28 which generally illustrate an exemplary duct assembly 931 . The duct assembly 931 may comprise a resilient deformable duct 930 to which a frame 932 has been secured. In other embodiments ducts may be comprised of other enclosed structures operative to conduct air therethrough. In a further exemplary embodiment, the frame 932 may be comprised of relatively rigid material and may include one or more tab portions 938 , one or more hook portions 934 , or combinations of tab portions 938 and hook portions 934 . In an exemplary embodiment, the frame 932 is adhered to the duct 930 with an adhesive 936 ( FIGS. 28 and 30 ). In a further exemplary embodiment, the one or more tab portions 938 cooperate with, for example, one or more fasteners 939 ( FIGS. 25 and 27 ) which can extend in and engage one or more apertures 937 in the component case 924 to reliably secure the duct 930 to the component case 924 . While the fastener 939 is shown as a screw, it is to be understood that other fasteners may be employed. In an exemplary embodiment, the one or more hook portions 934 are configured to cooperate with and engage one or more component case slots 935 to reasonably secure the duct 930 to the component case 924 . In the secured position the duct extends in surrounding relation of one or more processor case vents. While the duct assembly 931 is shown in exemplary fashion as secured to the component case 924 , the duct assembly 931 may be secured to the housing 912 , for example, the housing sidewall 916 , or to other cases or elements of the machine 910 .
In a further exemplary embodiment, as shown in FIG. 30 , the duct assembly 931 is adhered to the component case 924 with adhesive 936 . The adhesive 936 is secured to an edge face 933 , proximate the component case 924 , and the duct assembly 931 adhered to the component case 924 . As shown in FIG. 30 , the adhesive 936 may secure the frame 932 to the duct 930 and the adhesive 936 may secure the duct assembly 931 to the component case 924 . It is to be understood that the adhesive material used to secure the frame 932 to the duct 930 may not be the same adhesive material used to secure the duct assembly 931 to the component case 924 . In a further exemplary embodiment, the frame 932 is secured to the duct 930 by other means. As can be seen from FIG. 30 , forming the duct 930 from deformable resilient material, such as foam, enables the duct 930 to deform around the frame 932 thickness and contact the component case 924 .
In an exemplary embodiment, a method is performed. The fascia 986 is moved from a position adjacent the opening 22 ( FIG. 2 ) to the interior 20 of the housing 912 of the automated banking machine 910 , to a position away from the opening 22 . The component case 924 is moved from a position within the interior 20 of the housing 912 to a position at least partially extending through the opening 22 . The duct assembly 931 , at least partially secured to the component case 924 with the releasable resealable adhesive 936 , is released and separated from the component case 924 . A component (not shown), at least partially contained within the component case 924 is serviced. This may include replacing or adjusting a circuit card, processor board, a hard drive, a transformer or other component, for example. The duct assembly 931 is adhered to the component case 924 , and the component case 924 moved from the position at least partially extending through the opening 22 to the position within the interior 20 of the housing 912 . The fascia 986 is moved from the position away from the opening 22 of the housing 912 to the position adjacent the opening. In a further embodiment, the duct assembly 931 , comprising the resilient deformable duct 930 with releasable resealable adhesive 936 secured thereto, the duct 930 is deformed to adhere to the component case 924 . The duct 930 may also be comprised of combinations or portions of relatively rigid and other portions of resilient material. In a further embodiment, the duct assembly 931 , further comprising the duct frame 932 having at least one hook portion 934 and the component case 924 , further comprising the at least one slot 935 , the at least one hook portion 934 is mated and engaged with the at least one slot 935 . In a further embodiment, the duct assembly 931 further comprises the frame 932 having at least one tab portion 938 and an least one fastener 939 in operative connection with the at least one tab 938 and the component case 924 further includes at least one fastener hole 937 . The at least one fastener 939 is mated with the at least one fastener hole 937 . In some embodiments the duct 930 may be comprised of a relatively rigid material such as rigid plastic or sheet metal, for example.
In a further exemplary embodiment, a method is provided. The housing 912 is mounted in supporting connection with the chest 44 ( FIG. 2 ). The card reader 24 ( FIG. 3 ) is installed in operatively supported connection with the housing 912 , the display 928 is installed in operatively supported connection with the housing 912 , and a cash dispenser 64 ( FIG. 3 ) is installed in operatively supported connection with the housing 912 . The component case 924 , having at least one component case vent 943 , is installed in operatively supported connection with the housing 912 . The duct assembly 931 , including a duct 930 is adhered to the component case 924 . In a further exemplary embodiment, the duct assembly 931 further includes a frame 932 and the method further includes securing the frame 932 to the duct 930 . In a further exemplary embodiment, the frame 932 is adhered to the duct 930 . In a further exemplary embodiment, the frame includes at least one hook portion 934 and the component case 924 further includes at least one slot 935 , the slot 935 adapted to accept the at least one hook portion 934 , the method further comprising mating the at least one hook portion 934 and the at least one slot 935 . In a further exemplary embodiment, the frame 932 includes at least one tab portion 938 , the duct assembly 931 further includes at least one fastener 939 , and the component case 924 further includes at least one fastener hole 937 . The method further comprises mating the at least one fastener 939 and the at least one fastener hole 937 .
In still other embodiments a resilient duct may be positioned within the interior of the machine. The duct may extend in surrounding relation of one or more housing vents and processor case vents. The duct face at one or more ends may be secured to an adjacent wall surface with a resealable or a single use adhesive. In some embodiments the adhesive may be replenished each time the duct is reengaged.
While the exemplary embodiments include particular structures to achieve the desirable results, those having skill in the art may devise numerous other embodiments with other structures which employ the principles described herein and which are encompassed by the subject matter as claimed.
Turning now to FIG. 31 , there is shown therein a portion of an automated banking machine of a further exemplary embodiment. (See FIG. 1 for a general exemplary embodiment of an automated banking machine.) In this exemplary embodiment, a fascia assembly 589 comprises a fascia cover 588 operatively connected to a fascia frame 590 . While the fascia cover 588 and fascia frame 590 may be described in the exemplary embodiment as separate elements, it is to be understood the fascia cover 588 and the fascia frame 590 may in some embodiments be of a single-piece construction. Also shown in FIG. 31 is a support 580 . The support 580 may comprise a tray, which tray may further support automated banking machine components such as, by way of example only, a display 28 (e.g., FIG. 2 ), a card reader 24 (e.g., FIG. 2 ) and/or a receipt printer 30 (e.g., FIG. 2 ). The support 580 may comprise slides 84 (e.g., FIG. 2 ) either in combination with a tray or separately. The fascia assembly 586 is supported, at least in part, by the support 580 . The support 580 is further supportively connected to the housing 12 (e.g., FIG. 2 ) and/or the chest 40 (e.g., FIG. 2 ).
Turning now to FIG. 32 , there is illustrated an exploded isometric view of the exemplary fascia assembly 586 and exemplary support 580 of FIG. 31 further illustrating the exemplary features. The fascia frame 588 comprises at least one hook 582 and may further comprise two or more hooks 582 (not shown) in spaced-apart relation. The support 580 comprises at least one slot 578 of the exemplary embodiment and may further comprise two or more slots 578 . The at least one hook 582 and the at least one slot 578 are formed to enable the at least one hook 582 and the at least one slot 578 to engage and thereby at least partially secure the fascia assembly 586 to the support 580 . It is to be understood that either the fascia frame 590 or the support 580 may comprise a hook 582 and the other of the fascia frame 590 or the support 580 comprise a slot 578 .
Turning now to Figures and 33 and 34 , and with reference to FIG. 32 , the details of the engagement of the hook 582 and the slot 578 may be further understood. As the hook 582 is engaged with the slot 578 , the fascia assembly 589 becomes at least partially supported by the support 580 . As such, the fascia assembly 589 may be initially engaged and further secured by a single person. Further, the fascia assembly 589 may be unsecured and disengaged by a single person. As best seen in FIGS. 33 and 34 , the hook 582 may be offset from the slot 578 and thus provide a positive engagement between the hook 582 and the slot 578 . To further secure the fascia assembly 589 to the support 580 , one or more fasteners 584 may be utilized. By way of example only, as shown in FIGS. 33 and 34 , a screw 584 may engage screw holes 576 in the fascia frame 590 and in the support 580 .
The support 580 may further comprise one or more tabs 574 which may serve to guide the one or more hooks 582 into the one or more slots 578 . As with the hooks 582 and the slots 578 , it is to be understood that either the fascia frame 590 or the support 580 may comprise one or more tabs 574 .
In an exemplary method, referring also to FIGS. 2 , 3 , and 31 - 34 , the method comprises mounting a housing 12 in supporting connection with a chest 40 adapted for use in an automated banking machine 10 , the housing 12 comprising an interior 20 and at least one opening 22 into the interior 20 . The method comprises installing a card reader 24 in operatively supported connection with the housing 12 , wherein the card reader 24 is operative to read indicia on user cards corresponding to financial accounts. The method comprises installing a display 28 in operatively supported connection with the housing 12 . The method comprises installing a cash dispenser 64 in operatively supported connection with the housing 12 . The exemplary method comprises installing a printer 30 in operatively supported connection with the housing 12 and operative to print information corresponding to financial accounts and financial transactions. It is understood the card reader 24 , the display 28 , the cash dispenser 64 , and the printer 30 may be mounted onto various elements of the automated banking machine 10 , including, but not limited to, a support 580 which may comprise a tray. The method comprises installing the support 580 in operatively supported connection with the housing 12 , the support 580 moveable between a position substantially within the interior area 20 of the housing 12 and a position wherein at least a portion of the support 580 is extended through the housing opening 20 . (Best understood by reference to FIG. 2 .) The method comprises mounting a fascia assembly 589 to the support 580 , the fascia assembly 589 comprising a fascia frame 590 and a fascia cover 588 in operatively supported connection with the fascia frame 590 . At least one of the fascia frame 590 and the support 580 comprises at least a first hook 582 and the other comprises at least a first slot 578 , the at least first hook 582 and the at least first slot 578 formed to engage each other. The method comprises engaging the at least first hook 582 with the at least first slot 578 .
The exemplary method further comprises moving the at least first hook 582 to an offset position relative to the at least first slot 578 . (Best seen in FIGS. 33 and 34 .)
The exemplary method further comprises securing the fascia assembly 589 to the support 580 with, for example, a fastener 584 such as a screw.
The exemplary method further comprises moving the fascia assembly 589 to a secure closed position adjacent the housing opening 22 . (Best seen in FIG. 1 .)
In a further exemplary method, the method comprises moving a fascia assembly 589 in operatively supported connection with a housing 12 of an automated banking machine 10 from a secure closed position adjacent an opening 22 to an interior 20 of the housing 12 to a released away position away from the opening 22 . (Best seen in FIGS. 1 and 2 .) The automated banking machine 10 comprises a card reader 24 in operatively supported connection with the housing 12 and operative to read indicia corresponding to financial accounts on user cards, a display 28 in operatively supported connection with the housing 12 , a printer 30 in operatively supported connection with the housing 12 and operative to print information corresponding to financial accounts and financial transactions, a cash dispenser 64 in operatively supported connection with the housing 12 , and a support 580 in operatively supported connection with the housing 12 , the support 580 moveable between a position substantially within the interior 20 of the housing 12 and a position wherein at least a portion of the support 580 is extended through the housing opening 22 . (Best seen in FIGS. 1 and 2 .) The fascia assembly 589 comprises a fascia frame 590 and a fascia cover 588 in operatively supported connection with the fascia frame 590 . At least one of the fascia frame 590 and the support 580 comprises at least a first hook 582 and the other comprises at least a first slot 578 , the at least first hook 582 and the at least first slot 578 formed to engage each other. The method comprises disengaging the at least first hook 582 from the at least first slot 578 . The method comprises servicing at least one of a serviceable automated banking machine component. Such serviceable automated banking machine components include, for example, the card reader 24 , the display 28 , the printer 30 , and the cash dispenser 64 . The method comprises engaging the at least first hook 582 with the at least first slot 578 . The method comprises moving the fascia assembly 589 from the released away position from the opening 22 to the secure closed position adjacent the opening 22 . (Best seen in FIGS. 1 and 2 .)
The fascia assembly 589 may be secured to the support 580 with one or more fasteners 584 and the method further comprise releasing the one or more fasteners 584 securing the fascia assembly 586 to the support 580 .
The exemplary method further comprises securing the one or more fasteners 584 securing the fascia assembly 586 to the support 580 .
As previously mentioned, the rollout tray 80 is movably mounted in supporting connection with slides 84 . The rollout tray provides a device support for various types of transaction function devices. Rollout trays may have numerous different configurations and may vary with the size, type and operation of the device supported. In some embodiments the tray may include a support structure separable from the device. In other arrangements the tray (which is sometimes alternatively referred to as a device support) may include a frame or body of the device itself. The example slides 84 enable the device support to extend out of the housing opening 20 of the machine, such that components may be more readily serviced. Slides 84 may be held in engagement with vertically extending sidewalls 14 , 16 of the housing 12 through fasteners. The process of fastening the slides in position to the walls via the fasteners can be time consuming during assembly. Removal and installation of the slides is also time consuming during servicing activities in which the slide needs to be removed for access to portions of the serviceable device. In addition, when assembling the machine, the slide has to be installed properly in that the slide can be extended in the desired direction. Also, slides may break and need to be replaced. Further, if a machine is going to be reconfigured with a device support that is moveable between a position substantially within the interior 20 of the housing 12 and a position wherein at least a portion of the device support is extended through a housing opening in the rear of the machine, the slides may need to be repositioned in the housing to accommodate the device support.
FIGS. 35-52 illustrate an exemplary embodiment that overcomes the above-mentioned problems by providing an apparatus that allows for a quick and easy way to install and remove slides that support device supports. In addition, the apparatus includes first and second slides 1000 , 1002 that can be engaged with the housing 12 through a set of slots to extend the device support through the front of the machine, or the same slides can be engaged with the same set of slots to extend the device support through the rear of the machine.
In this embodiment, the first and second slides 1000 , 1002 may be configured to support components of the machine 10 such as printers, check acceptors, and recycler modules on the rollout tray 80 . However, the slides 1000 , 1002 may be configured to support machine components on the other previously mentioned rollout trays and support 580 , or any other device support that is moveable between a position substantially within the interior 20 of the housing 12 and a position wherein at least a portion of the device support is extended through a housing opening. The exemplary slides 1000 , 1002 may be removably mounted to wall portions 1004 R, 1004 L of associated walls of the housing 12 . Each portion may be a separate piece that is within the housing. Alternatively, each wall portion may be formed in one piece with a sidewall or interior wall associated with the housing. The example right wall portion 1004 R (best seen in FIG. 37 ) of the right sidewall 16 , or other wall, is a minor image of the left wall portion 1004 L (best seen in FIGS. 40 and 41 ) of the left sidewall 14 or other wall. The right wall portion 1004 R includes a pair of slots, which are referred to herein as front slot 1006 and rear slot 1008 as depicted in FIG. 37 .
Referring to FIG. 38 , the example front slot 1006 is generally inverted L-shaped and includes a horizontally extending upper leg portion 1010 and a vertically extending lower leg portion 1012 . The upper leg portion 1010 extends a further distance in the rearward direction (relative to the front of the machine housing) than the lower leg portion 1012 . The upper leg portion 1010 is bounded by vertically extending front and rear ends 1014 , 1016 , and horizontally extending top and bottom ends 1018 , 1020 . The front and rear ends 1014 , 1016 are interconnected to each other by the top end 1018 . The bottom end 1020 extends forwardly from the rear end 1016 a distance less than the length of the top end 1018 . The bottom end 1020 includes a horizontal surface 1022 that in the operative position of the machine faces upwardly. The upper leg portion 1010 is open between the bottom end 1020 and the front end 1014 . The lower leg portion 1012 is bounded by vertically extending front and rear ends 1024 , 1026 are interconnected by a bottom end 1028 . The front end 1024 of the lower leg portion 1012 is positioned forwardly offset from the front end 1014 of the upper leg portion 1010 to define a step 1030 . In an operative position the step 1030 includes a step surface 1032 that in the operative position of the machine faces downwardly. The lower leg portion 1012 is open at its top, which is opposite of the lower leg bottom end.
Referring to FIG. 39 , the exemplary rear slot 1008 is a mirror image of the front slot and has a generally inverted L-shaped and in the operative position includes a horizontally extending upper leg portion 1034 and a vertically extending lower leg portion 1036 . The upper leg portion 1034 extends further in the forward direction (relative to the machine housing) than the lower leg portion 1036 . The upper leg portion 1034 is bounded by vertically extending front and rear ends 1038 , 1040 , and horizontally extending top and bottom ends 1042 , 1044 . The front and rear ends 1038 , 1040 are interconnected to each other by the top end 1042 . The bottom end 1044 extends rearwardly from the front end 1038 a distance less than the length of the top end 1042 . The bottom end 1044 includes a horizontal surface 1046 that in the operative position faces upwardly. The upper leg portion 1034 is open between the bottom end 1044 and the rear end 1040 . The lower leg portion 1036 is bounded by vertically extending front and rear ends 1048 , 1050 that are interconnected by a horizontally extending bottom end 1052 . The rear end 1050 of the lower leg portion 1036 is positioned rearwardly offset from the rear end 1040 of the upper leg portion 1034 to define a step 1054 . The step includes a step surface 1056 that in the operative position faces downwardly. The lower leg portion 1036 is open at its top, which is opposite the lower leg portion bottom end.
FIGS. 40 and 41 show rear and left side isometric views with respect to the machine 10 of portions of the left wall portion 1004 L of the left side wall 14 or other wall of the housing 12 . As depicted in FIGS. 40 and 41 , the left wall portion 1004 L includes a front slot 1058 and a rear slot 1060 . Referring to the rear and left side isometric view of FIG. 41 , the front slot 1058 is a generally inverted L-shape and in the operative position includes a horizontally extending upper leg portion 1062 and a vertically extending lower leg 1064 . The upper leg portion 1062 extends a further distance in the rearward direction than the lower leg portion 1064 . The upper leg portion 1062 is bounded by vertically extending front and rear ends 1066 , 1068 , and horizontally extending top and bottom ends 1070 , 1072 . The front and rear ends 1066 , 1068 are interconnected to each other by the top end 1070 . The bottom end 1072 extends forwardly from the rear end 1068 a distance less than the length of the top end 1070 . The bottom end 1072 includes a horizontal surface 1074 that in the operative position faces upwardly. The upper leg portion 1062 is open between the bottom end 1072 and the front end 1066 . The lower leg portion 1064 is bounded in the operative position by vertically extending front and rear ends 1076 , 1078 that are interconnected by a horizontally extending a bottom end 1079 . The front end 1076 of the lower leg portion 1064 is positioned forwardly offset from the front end 1066 of the upper leg portion 1062 to define a step 1080 . The step includes a step surface 1082 that in the operative position faces downwardly. The lower leg portion 1064 is open at its top.
Referring to the rear and left side isometric view of FIG. 40 , the rear slot 1060 is a generally inverted L-shape and includes a horizontally extending upper leg portion 1086 and a vertically extending lower leg portion 1088 . The upper leg portion 1086 extends further in the forward direction than the lower leg portion 1088 . The upper leg portion 1086 is bounded by vertically extending front and rear ends 1090 , 1092 , and horizontally extending top and bottom ends 1094 , 1096 . The front and rear ends 1090 , 1092 are interconnected to each other by the top end 1094 . The bottom end 1096 extends rearwardly from the front end 1090 a distance less than the length of the top end 1094 . The bottom end 1096 includes a horizontal surface 1098 that in the operative position faces upwardly. The upper leg portion 1086 is open between the bottom end 1096 and the rear end 1092 . The lower leg portion 1088 is bounded in the operative position by vertically extending front and rear ends 1100 , 1102 that are interconnected by a horizontally extending bottom end 1104 . The rear end 1102 of the lower leg portion 1088 is positioned rearwardly offset from the rear end 1092 of the upper leg portion 1086 to define a step 1106 . The step 1106 includes a step surface 1108 that in the operative position faces downwardly. The lower leg portion 1088 is open at its top.
Referring to FIGS. 35 and 36 , the exemplary first slide 1000 includes a first channel rail 1110 that slidably receives a second channel rail 1112 . The second channel rail 1112 slidably receives a third channel rail 1114 . When the rollout tray 80 is in the retracted position as shown in FIG. 1 , the channel rails 1110 , 1112 , and 1114 are retracted in telescoping relation such that all of the channel rails are positioned within interior of the housing 12 . When the rollout tray 80 moves toward the extended postion as shown in FIG. 2 , the second channel rail 1112 first slides relative to the first channel rail 1110 in engagement therewith in the direction toward the extended position of the rollout tray 80 until it is fully extended relative to the first channel rail 1110 . Then, the third channel rail 1114 slides along the second channel rail 1112 in the direction toward the extended position of the rollout tray 80 . The third channel rail 1114 is fully extended from the second channel rail 1112 when the rollout tray 80 is in the extended position.
Referring to FIGS. 42 and 43 , the exemplary first channel rail 1110 has in operative fixed engagement therewith first and second mounting tabs 1116 , 1118 . The exemplary tabs 1116 , 1118 are made of generally rigid but deformable material such as sheet steel. As seen in FIG. 43 , the exemplary first tab 1116 in the operative position extends generally vertically. That is, a lateral axis 1120 of the first tab 1116 is vertical. The first tab 1116 includes a proximal portion 1122 that extends outward relative to an outer side 1124 of the first channel rail 1110 in a direction transverse to the longitudinal axis 1126 of the first slide 1000 . The exemplary first tab 1116 also includes a distal portion 1128 that extends from the proximal portion 1122 in a first direction. The first direction in the example embodiment is the same direction of movement as the rollout tray 80 moves from the extended position to the retracted position wherein the device is within the interior of the housing 12 . The exemplary distal portion 1128 terminates in an end portion 1130 . The end portion 1130 flares outwardly or angles away from the outer side 1124 of the first channel rail 1110 with increasing relative displacement in the first direction. The exemplary end portion 1130 allows the first tab 1116 to accommodate for acceptance in the gap bounded by the first tab, wall portions having somewhat different thicknesses.
As seen in FIG. 42 , the exemplary second tab 1118 in the operative position is oriented generally horizontally. That is, the lateral axis 1134 of the second tab 1118 is horizontal. The second tab 1118 includes a proximal portion 1136 that extends outward relative to the outer side 1124 of the first channel rail 1110 in a direction transverse to the longitudinal axis 1126 of the first slide 1000 . The second tab 1118 also includes a distal portion 1140 that in the operative position extends downwardly from the proximal portion 1136 . The distal portion 1140 terminates at an end portion 1142 . The exemplary end portion 1142 flares outwardly with increasing relative downward displacement, away from the outer side 1124 of the first channel rail 1110 . The end portion 1142 bounds a gap that also allows the second tab 1118 to accommodate wall portions having somewhat different thickness.
Referring to FIGS. 47 and 48 , the exemplary second slide 1002 includes a first channel rail 1144 that slidably receives a second channel rail 1146 . The second channel rail 1146 slidably receives a third channel rail 1148 . When the rollout tray 80 is in the retracted position as shown in FIG. 2 , the channel rails 1144 , 1146 , and 1148 are retracted in telescoping relation such that all of the rails are positioned within interior of the housing 12 . When the rollout tray 80 moves toward the extended postion as shown in FIGS. 47 and 48 , the second channel rail 1146 first slides along in supported connection with first channel rail 1144 in the direction toward the extended position of the rollout tray 80 until it is fully extended from the third channel rail 1148 . Then, the third channel rail 1148 slides along the second channel rail 1146 in the direction toward the extended position of the rollout tray 80 . The third channel rail 1148 is fully extended from the second channel rail 1146 when the rollout tray 80 is in the extended position.
Referring to FIGS. 44 and 45 , the exemplary first channel rail 1144 of the second slide 1002 is in operatively fixed engagement with first and second mounting tabs 1150 , 1152 . The tabs 1150 , 1152 are made of generally rigid but deformable material such as sheet steel. Referring to the rear and left side isometric view of FIG. 44 , the exemplary first tab 1150 is oriented generally vertically in the operative position. That is, the lateral axis 1154 of the first tab 1150 is vertical. The first tab 1150 includes a proximal portion 1156 that extends in a direction away from the outer side 1158 of the first channel rail 1144 in a direction transverse to the longitudinal axis 1160 of the second slide 1002 . The exemplary first tab 1150 also includes a distal portion 1162 that extends from the proximal portion 1156 in a first direction and bounds a gap. The first direction is the same direction of movement of the rollout tray 80 from the extended position to the retracted position within the interior of the housing 12 . The distal portion 1162 terminates into an end portion 1164 . The exemplary end portion 1164 flares outwardly away from the outer side 1158 of the first channel rail 1144 with increasing distance in the first direction. The angled end portion 1164 allows the first tab 1150 to accommodate wall portions having different thicknesses.
Referring to the rear and left side isometric view of FIG. 45 , the exemplary second tab 1152 is oriented generally horizontally in the operative position. That is, the lateral axis 1166 of the second tab 1152 is horizontal. The second tab 1152 includes a proximal portion 1168 that extends outwardly away from the outer side 1158 of the first channel rail 1144 in a direction transverse to the longitudinal axis 1160 of the second slide 1002 . The second tab 1152 also includes a distal portion 1170 that extends downwardly from the proximal portion 1168 in the operative position. The distal portion 1170 terminates in an end portion 1172 . The exemplary end portion 1172 flares outwardly and angles downwardly and away from the outer side 1158 of the first channel rail 1144 . The end portion 1172 allows the gap bounded by the second tab to accommodate wall portions having somewhat different thickness.
The exemplary first slide 1000 is removably mounted to the right wall portion 1004 R in a front-load configuration of the machine 10 in which the rollout tray 80 and device supported thereby moves forwardly through the front opening 22 of the housing 12 from the retracted position to the extended position. As represented in FIG. 43 , when the first slide 1000 is operatively engaged with the right wall portion 1004 R, the first tab 1116 extends in and engages the rear slot 1008 . The proximal portion 1122 of the first tab 1116 extends in the lower leg 1036 portion of the rear slot 1008 and the distal portion 1128 extends rearwardly beyond the rear end 1050 of the lower leg. The gap bounded by distal portion 1128 engages an outer side surface 1132 of the right wall portion 1004 R that underlies inner surface 1174 of the first tab 1116 . In this position, an outer side surface 1124 of the first channel rail 1110 engages an inner side surface 1176 of the right wall portion 1004 R. This arrangement provides firm yet releasable engagement of the slide and wall, and helps prevent horizontal movement transverse to the longitudinal axis 1126 of the first slide 1000 . Also, the rear end 1050 of the slot engages the inner surface 1174 of the first tab 1116 to help prevent the first slide 1000 from moving further rearwardly. Bottom end 1178 of the first tab 1116 engages the bottom end 1052 of the lower leg portion 1036 to help prevent the first slide 1000 from moving downwardly. Also, in this position, the horizontal step surface 1056 ( FIG. 39 ) of the step 1054 of the slot extends above top end 1180 of the first tab 1116 . The step 1054 of the slot may be configured to be in close proximity to the top end 1180 or alternatively engage the top end 1180 of the tab to prevent the first tab 1116 from moving upwardly and thus prevent the first slide 1000 when in engaged relation from moving vertically relative to the wall portion. This feature may be especially useful because the extension of the rollout tray 80 out of the machine 10 in some arrangements tends to cause the end of the first slide 1000 furthest away from the opening of the housing 12 through which the tray is extended to move upwardly.
As seen in FIG. 42 , in the example arrangement when the first slide 1000 is mounted in engaged relation with the right wall portion 1004 R, the second tab 1118 is in engaged relation with the front slot 1006 . In particular, the proximal portion 1136 of the second tab 1118 extends in the upper leg portion 1010 of the front slot 1006 and the distal portion 1140 of the second tab 1118 extends downwardly beyond the bottom end 1020 of the upper leg portion 1010 . The gap bounded by distal portion 1140 accepts and engages the outer side surface 1132 of the right side wall portion 1004 R at the inner surface 1182 of the second tab 1118 . The tab may be deformed from its original position so that spring force is applied by the tab to hold the slide in the operative position relative to the wall. An outer side 1124 surface operatively associated with the first channel rail 1110 engages the inner side 1176 of the right wall portion 1004 R. This arrangement helps prevent horizontal movement transverse to the longitudinal axis 1126 of the first slide 1000 . Also, part of the horizontal surface 1022 of the bottom end 1020 engages the inner surface 1182 of the second tab 1118 to help prevent the first slide 1000 from moving downwardly. The second tab 1118 is also spaced forwardly from the rear end 1016 of the upper leg portion 1010 , and spaced rearwardly from the front end 1024 of the lower leg 1012 .
To install the exemplary first slide 1000 in engagement with to the right wall portion 1004 R, the first tab 1116 is inserted through the rear slot 1008 and the second tab 1118 is inserted through the upper leg portion 1010 of the front slot 1006 . The first slide 1000 is then moved downwardly until the second tab 1118 engages the horizontal surface 1022 of the bottom end 1020 of the upper leg portion 1010 . Then, the first slide 1000 is moved rearwardly until the first tab 1116 engages the rear end 1050 of the lower leg portion 1036 of the rear slot 1008 . This holds the slide in position where it is supported by bottom ends 1020 and 1052 . Step 1054 prevents the inner end of the slide from moving vertically when the tray is extended. The configuration of the exemplary spring-like tabs hold the slide firmly engaged with the wall. To remove the first slide 1000 from engagement with the right wall portion 1004 R, the first slide 1000 is moved forwardly until the step 1054 is not over the top end 1180 of the first tab 1116 . Then, the first slide 1116 is moved upwardly and away from the right bracket 1004 R to withdraw the tabs 1116 , 1118 from their respective slots 1006 , 1008 .
The second slide 1002 is removably engaged with the left wall portion 1004 L of a front loaded machine ( FIG. 2 ) in which the rollout tray 80 moves forwardly through the front opening 22 of the housing 12 from the retracted position to the extended position. As seen in the rear and left side isometric view of FIG. 44 , when the second slide 1002 is engaged with the left wall portion 1004 L, the first tab 1150 extends in and engages the rear slot 1060 . The proximal portion 1156 of the first tab extends through the lower leg portion 1088 of the rear slot 1060 , and the distal portion 1162 extends rearwardly beyond the rear end 1102 ( FIG. 40 ) of the lower leg portion 1088 . The distal portion 1162 accepts the wall portion adjacent the slot in the gap bounded thereby and engages the outer side surface 1196 of the left wall portion 1004 L at the inner surface 1188 of the first tab 1150 . The outer side surface 1196 operatively connected to the first channel rail 1144 engages the inner side 1190 of the left wall portion 1004 L. This arrangement helps prevent horizontal movement transverse to the longitudinal axis 1160 of the second slide 1002 . Also, the rear end 1102 engages the inner surface 1188 of the first tab 1150 to prevent the second slide 1002 from moving rearwardly. Bottom end 1192 of the first tab 1150 engages the bottom end 1104 of the lower leg portion 1088 to help prevent the second slide 1002 from moving downwardly. Also, in this position, the horizontal surface 1108 of the step 1106 extends over top end 1194 of the first tab 1150 . This step 1106 may be in close proximity to the top end 1194 or alternatively engage the top end 1194 to prevent the first tab 1150 from moving upwardly and thus prevent the second slide 1002 from moving upwardly. This feature may be useful because the extension of the rollout tray 80 out of the machine 10 tends to cause the end of the second slide portion 1002 furthest away from the opening to the interior of the housing 12 , to move upwardly.
As seen in FIG. 45 , when the second slide 1002 is mounted to the left wall portion 1004 L, the second tab 1152 extends in the front slot 1058 . The proximal portion 1168 of the second tab 1152 extends through the upper leg portion 1062 of the front slot 1058 and the distal portion 1170 of the second tab 1152 extends downwardly beyond the bottom end 1072 of the upper leg portion 1062 . The distal portion 1170 accepts a portion of the wall adjacent the slot into the gap and engages the outer side surface 1196 of the left wall portion 1004 L at the inner surface 1198 of the second tab 1152 . The outer side surface 1158 in operative connection with the first channel rail 1144 , engages the inner side surface 1190 of the left wall portion 1004 L. This arrangement helps prevent horizontal movement transverse to the longitudinal axis of the second slide 1002 . Also, part of the horizontal surface 1074 of the bottom end 1072 engages the second tab 1152 to help prevent the second slide 1002 from moving downwardly. The second tab 1152 is also spaced forwardly from the rear end 1068 of the upper leg 1062 , and spaced rearwardly from the front end 1076 of the lower leg 1064 .
To install the second slide 1002 in engagement with the left wall portion 1004 L, the first tab 1150 is extended in the rear slot 1060 and the second tab 1152 is extended in the upper leg portion 1062 of the front slot 1058 . The second slide 1002 is the moved downwardly until the inner surface 1198 of second tab 1152 engages the horizontal surface 1074 of the bottom end 1072 of the upper leg portion 1062 . Then, the second slide 1002 is moved rearwardly until the second tab 1152 engages the rear end 1102 of the lower leg portion 1088 of the rear slot 1060 . The second slide is held in firm fixed releasable engagement with the wall portion. To remove the second slide 1002 from engagement with the left wall portion 1004 L, the second slide 1002 is moved forwardly until the step 1106 is not over the top end 1194 of the first tab 1150 . Then, the second slide 1002 is moved upwardly and away from the left wall portion 1004 L to withdraw the tabs 1150 , 1152 from their respective slots 1060 , 1058 .
The second slide 1002 is removably mounted to the right wall portion 1004 R (as best depicted in FIGS. 47 and 48 ) in a rear load configuration of the machine or a machine in which the rollout tray 80 moves rearwardly through a rear opening 1195 of the housing 12 from the retracted position to the extended position as represented in FIG. 46 . As shown in FIG. 49 , when the second slide 1002 is mounted to the right wall portion 1004 R, the first tab 1150 engages the front slot 1006 . In particular, the proximal portion 1156 of the first tab 1150 extends in the lower leg portion 1012 of the front slot 1006 and the distal portion 1162 extends forwardly beyond the front end 1024 of the lower leg portion 1012 such that the wall portion adjacent the slot extends in the gap bounded by the tab. The distal portion 1162 engages the outer side surface 1132 of the right wall portion 1004 R at the inner surface 1188 of the first tab 1150 , and the outer side 1158 of the first channel rail 1144 engages the inner side 1176 ( FIG. 47 ) of the right wall portion 1004 R. This arrangement helps prevent horizontal movement transverse to the longitudinal axis 1160 of the second slide 1002 . Also, the front end 1024 engages the inner surface 1188 of the first tab 1150 to help prevent the second slide 1002 from moving forward relative to the wall portion. The bottom end 1192 of the first tab 1150 engages the bottom end 1028 of the lower leg portion 1012 to help prevent the second slide 1002 from moving downwardly. Also, in this position, the horizontal step surface 1032 of the step 1030 extends over the top end 1194 of the first tab 1150 . This step 1030 may be in close proximity to the top end 1194 or alternatively may engage the top end 1194 to prevent the first tab 1150 from moving upwardly and thus prevent the second slide 1002 from moving vertically. This feature is especially useful because the extension of the rollout tray 80 out of the machine tends to cause the end of the second slide 1002 furthest away from the opening to the interior of the housing 12 through which the tray is extended to move upwardly.
As seen in FIG. 50 , when the second slide 1002 is mounted to the right wall portion 1004 R, the second tab 1152 engages the rear slot 1008 . In particular, the proximal portion 1168 of the second tab 1152 extends through the upper leg portion 1034 of the rear slot 1008 and the distal portion 1170 of the second tab 1152 extends downwardly beyond the bottom end 1044 of the upper leg portion 1034 such that the wall portion adjacent the slot extends in the gap bounded by the tab. The distal portion 1170 engages the outer side surface 1132 of the right wall portion 1004 R at the inner surface 1198 of the second tab 1152 , and the outer side surface 1158 in operative connection with the first channel rail 1144 engages the inner side 1176 ( FIG. 47 ) of the right wall portion 1004 R. This exemplary arrangement helps prevent horizontal movement transverse to the longitudinal axis 1160 of the second slide 1002 . Also, part of the horizontal surface 1046 of the bottom end 1044 engages the inside surface of the second tab 1152 to help prevent the second slide 1002 from moving downwardly. The exemplary second tab 1152 is also spaced forwardly from the front end 1038 of the upper leg portion 1034 , and spaced rearwardly from the rear end 1050 of the lower leg portion 1036 .
To engage the second slide 1002 to the right wall portion 1004 R, the first tab 1150 is extended through the front slot 1006 and the second tab 1152 is extended through the upper leg portion 1034 of the rear slot 1008 . The second slide 1002 is then moved downwardly until the second tab 1152 engages the horizontal surface 1046 of the bottom end 1044 of the upper leg portion 1034 . Then, in the exemplary method the second slide 1002 is moved forwardly until the first tab 1150 engages the front end 1024 of the lower leg portion 1012 of the front slot 1006 . The slide is thus held in engaged relation with the wall portion. To remove the second slide 1002 from engagement with the right wall portion 1004 R, the second slide 1002 is moved rearwardly until the step 1030 is not in overlying relation to the top end 1194 of the first tab 1150 . Then, the second slide 1002 is moved upwardly and away from the right wall portion 1004 R to withdraw the tabs 1150 , 1152 from their respective slots 1006 , 1008 .
The first slide 1000 is removably mounted to the left wall portion 1004 L of a rear load machine or in configuration of the machine 10 in which the rollout tray 80 moves outwardly through the rear opening 1195 of the housing 12 from the retracted position to the extended position ( FIG. 46 ). As seen in the rear and left side isometric view of FIG. 52 , when the first slide 1000 is mounted on the left wall portion 1004 L, the first tab 1116 extends in the front slot 1058 . In particular, the proximal portion 1122 of the first tab 1116 extends through the lower leg portion 1064 of the front slot 1058 and the distal portion 1128 extends forwardly beyond the front end 1076 of the lower leg portion 1064 such that the wall adjacent the slot extends in the gap bounded by the tab. The distal portion 1128 engages the outer side surface 1196 of the left wall portion 1004 L at the inner surface 1174 of the first tab 1116 , and the outer side surface 1124 in operative connection with first channel rail 1110 engages the inner side 1190 of the left wall portion 1004 L. This arrangement helps prevent horizontal movement transverse to the longitudinal axis 1126 of the first slide 1000 . Also, the front end 1076 engages the inner surface 1174 of the first tab 1116 to help prevent the first slide 1000 from moving forwardly. The bottom end 1178 of the first tab 1116 engages the bottom end 1179 of the lower leg portion 1064 to help prevent the first slide 1000 from moving downwardly. Also, in this position, the horizontal step surface 1082 of the step 1080 extends in overlying relation of the top end 1180 of the first tab 1116 . The step 1080 may be in close proximity to the top end 1180 or alternatively may engage the top end 1180 to prevent the first tab 1116 from moving upwardly and thus prevent the first slide 1000 from moving vertically. This feature is useful because the extension of the rollout tray 80 out of the machine tends to cause the end of the first slide 1000 furthest away from the opening of the housing 12 through which the tray is extended to move upwardly.
As seen in the rear and left side isometric view of FIG. 51 , when the first slide 1000 is engaged with the left wall portion 1004 L, the second tab 1118 extends in the rear slot 1060 . In particular, the proximal portion 1136 of the second tab 1118 extends through the upper leg portion 1086 of the rear slot 1060 and the distal portion 1140 of the second tab 1118 extends downwardly beyond the bottom end 1096 of the upper leg portion 1086 so as to hold an area of the wall adjacent the slot in the gap bounded by the tab. The distal portion 1140 engages the outer side surface 1196 of the left wall portion 1004 L at the inner surface 1182 of the second tab 1118 , and the outer side surface 1124 in operative connection with the first channel rail 1110 engages the inner side surface 1190 of the left bracket 1004 L. This arrangement helps prevent horizontal movement transverse to the longitudinal axis 1126 of the first slide 1000 . Also, part of the horizontal surface 1098 of the bottom end 1096 engages the inner surface 1182 of the second tab 1118 to help prevent the first slide 1000 from moving downwardly. The second tab 1118 is also spaced rearwardly from the front end 1090 of the upper leg portion 1086 , and spaced forwardly from the rear end 1102 of the lower leg portion 1088 .
To engage the first exemplary slide 1000 and the left wall portion 1004 L, the first tab 1116 is extended in the front slot 1058 and the second tab 1118 is extended in the upper leg portion 1086 of the rear slot 1060 . In an exemplary method, the first slide 1000 is moved downwardly until the second tab 1118 engages the horizontal surface 1098 of the bottom end 1096 of the upper leg portion 1086 . Then, the first slide 1000 is moved forwardly until the first tab 1116 engages the front end 1076 of the lower leg portion 1064 of the front slot 1058 . The first slide is thus held in operative engagement with the wall through the action of the tabs. To remove the first slide 1000 from the left wall portion 1004 L, the first slide 1000 is moved rearwardly until the step 1080 is not in overlying relation of the top end 1180 of the first tab 1116 . Then, the first slide 1000 is moved upwardly and away from the left wall portion 1004 L to withdraw the tabs 1116 , 1118 from their respective slots 1058 , 1060 . The exemplary tabs 1116 , 1118 , 1150 , and 1152 are configured such that the gaps bounded thereby are in close tolerance with the thickness of their associated wall portions, and once engaged the exemplary tabs utilize the resilient properties of the exemplary material to provide a spring type clamping force on the area of the wall in the gap which tends to hold the associated slide in engagement with the bracket.
Alternatively, the first slide may be configured to be removably mounted to the right wall portion and the second slide may be removably mounted to the left wall portion in both the front load and rear load configurations. In this arrangement, the first slide may include first and second tabs that engage rear and front slots, respectively, of the right wall portion in the front load configuration. In the rear load configuration, the first and second tabs of the first slide engage the front and rear slots, respectively, of the right wall portion. In this arrangement, the second slide may include first and second tabs that engage rear and front slots, respectively, of the left wall portion in the front load configuration. In the rear loaded configuration, the first and second tabs of the second slide engage the front and rear slots, respectively, of the left wall portion.
In the exemplary embodiment, the slots are configured to be generally mirror images of one another. This facilitates the configuration of the automated banking machine such that the slides and the device supporting rollout tray which is attached thereto can be readily configured such that the tray can be extended from an opening at the front of the housing or alternatively from the rear of the housing. However, it should be understood that in other example embodiments the principles discussed herein may be applied to slots that are not minor image or symmetric configurations. In addition, in the exemplary embodiment the slots are formed in the wall portions, while the tabs are in operatively fixed connection with the slides. In other exemplary embodiments, this configuration may be changed. For example, in some example embodiments the slots may in operatively fixed connection with the slides, and the tabs may be in operatively fixed connection with the wall portions. Alternatively in other embodiments, a tab and slot may be associated with a single slide, while an engagingly configured slot and tab may be in operatively fixed connection with the adjacent wall portion. Further, it should be understood that while in the exemplary embodiment each slide includes two contact points, including interengaging tabs and slots which hold the respective slide in engagement with a wall portion, in other embodiments other arrangements may be used. This may include for example a single interengaging tab and slot for each slide. This might be used for example where the tray or slide structure is supported within the machine by other structures. This might include for example a bracket which supports the slides in an area away from the interengaging tab and slots. Similarly in other alternative embodiments, each slide may include more than two interengaging tab and slot arrangements. As can be appreciated, numerous configurations may be achieved using the principles described herein.
Further, while the exemplary embodiment has discussed the use of two slides disposed from one another that support a tray that can be extended from the machine, other embodiments may use other configurations. This might include for example a single slide which is sufficient to hold a tray which can be extended out of the machine. Further in other embodiments, trays may include two or more vertically disposed slides engaged with a wall portion. A tray operative to hold a transaction function device may be engaged with both of the vertically disposed slides which are attached to generally the same wall. This will enable the tray and the associated device to be extended out of an opening from the machine.
In the exemplary embodiment described, the configuration of the tabs and slots are such that the slides may be attached to the wall portions by engaging the tabs in the slots and moving the slide so as to position the tabs in the desired position relative to the slots. Because of the engaging force of the exemplary tabs holding the wall portion adjacent to the slots in the gap formed by the tabs, there may be no need to have any additional fasteners or other devices for holding the tabs in engagement with the wall portion. However, in some embodiments it may be desirable to have such fasteners. Such fasteners may have various forms. For example in some embodiments a surface associated with a slide may include an aperture which can accept a fastener so as to engage the respective slide in engagement with the side wall. One or more such fasteners may prevent the slide from moving relative to the side wall, so as to prevent disengagement of the slide and tray therefrom. Alternatively in some embodiments, a spring loaded plunger type structure may be used to engage an aperture either in the slide or the side wall. Engagement of a plunger in the aperture may likewise prevent relative movement of the slide unless the plunger has been retracted from engagement with the aperture. Alternatively and/or in addition, projections in operative connection with either the slide or side wall may engage corresponding openings or apertures in the opposite structure in a manner that prevents relative movement of the slide so as to cause the slide to disengage. Again in this case, the projection may be movable so as to disengage and allow the slide to be move. Numerous different releasable fastening arrangements may be applied, holding the slides in engagement with the walls in various embodiments.
Of course it should be understood that while in the exemplary embodiments the slide and tray structures discussed have been used in connection with supporting devices from vertically extending side walls, the principles described herein may also be utilized in connection with supporting structures from horizontally or other types of walls within an automated banking machine. For example, one or more slides may be utilized to support a tray structure associated with a device in operatively supported connection with a horizontally extending top wall of the chest. This might include for example a processor or other device which is positioned within an upper portion of the housing. Alternatively and/or in addition, one or more such structures may be utilized in connection with supporting a device in movably mounted connection with a horizontal structure at the top, bottom or intermediate portion of the housing. In addition it should be understood that while exemplary structures have a generally fixed base of a slide structure in connection with a wall of a machine, other arrangements may associate the base of the slide structure with the tray or device housing so that the base of the slide is movable with the tray and the device. Further it should be understood that while movable tray structures and supporting devices may be often used in an upper housing portion of an automated banking machine, such structures may also be utilized within the chest portion of a machine.
As can be appreciated, an advantage of exemplary embodiments may include the ability to use a common housing structure for both front load and rear load automated banking machines. This may facilitate assembly in a factory environment, such that assembly line workers may engage the slides in connection with the slots and position the slides appropriately so as to firmly hold the slides in engagement with the walls or other supporting structures. The trays supporting the devices can then be engaged with the slides so as to facilitate extending the devices outward through an opening from the housing as is appropriate from the machine. For example, in the front load machine the slides individually or as part of a tray assembly may be moved to extend tabs into the slots in the manner previously described, with the tabs positioned relative to the slots so as to achieve a firm engagement between the tabs, the slides, and the walls of the enclosure. In exemplary embodiments the symmetrical configuration will enable construction of the machine so as to allow the tray to be extended from either an opening on the front of the housing or an opening on the back of the housing, as may be appropriate for the particular machine. In some situations, housing might have openings at both the front and the back. As can be appreciated for example, a similar housing may be used for a front load machine where a fascia associated with the user interface is movably mounted relative to the machine. One or more trays to support devices within the machine may be movably mounted so as to extend through the front opening of the housing. Likewise, a rear load machine may include a fascia that is in fixed relation to the front of the housing. The housing may include a door controlled by a lock. The door may be opened from the rear of the housing. In such a rear load configuration, trays can be extended through the rear opening of the housing when the access door is open. In still other embodiments, the fascia may be movable away from the housing, for example supported on tray structures like those described in the exemplary embodiment. The rear of the housing may also have a door which can be opened. In such configurations, trays may be configured to be extendable from either the front opening or the rear opening. Of course these approaches are exemplary, and in other embodiments other approaches may be used.
Also, sometimes after a machine has been deployed, it may be desirable to change devices that are utilized in the machine. This may include for example adding devices to the machine that were not originally included at the time of manufacture. This might include for example adding a device that can accept and image checks. It may alternatively include for example adding a device that can both accept and dispense currency bills. Alternatively, a change in devices may include adding a coin dispenser, a passbook printer, or other devices not originally present in the machine. Alternatively, such modifications may involve removing a device that was installed at the time of manufacture, and replacing it with a different device.
The principles described may be applied in such circumstances to facilitate the reconfiguration of such machines in the field. This may be done by including slot structures in the wall portions at appropriate positions for many different types of configurations of devices that might be possible for a given housing structure. For example, although the machine may not be originally manufactured to include a check acceptor, slots may be included in the wall portions to support slides which support a check acceptor should one need to be installed in the future. By anticipating the range of different devices that may be installed within the machine, a field service technician may readily move existing slide and tray structures which support different types of devices, and relocate and install different ones as appropriate. Thus the time and effort associated with installing new devices and/or reconfiguring the machine to remove and include different devices may be reduced. Numerous different approaches and benefits may be achieved using the principles described herein.
Thus the automated banking machines and systems of the exemplary embodiments may achieve one or more of the above stated objectives, eliminate difficulties encountered in the use of prior devices and systems, solve problems and attain the desirable results described herein.
In the foregoing description certain terms have been used for brevity, clarity and understanding, however no unnecessary limitations are to be implied therefrom because such terms are for descriptive purposes and are intended to be broadly construed. Moreover, the descriptions and illustrations herein are by way of examples and the invention is not limited to the details shown and described.
In the following claims any feature described as a means for performing a function shall be construed as encompassing any means capable of performing the recited function, and shall not be deemed limited to the particular means shown in the foregoing description or mere equivalents thereof.
Having described the features, discoveries and principles of the invention, the manner in which it is constructed and operated, and the advantages and useful results attained; the new and useful structures, devices, elements, arrangements, parts, combinations, systems, equipment, operations, methods, processes and relationships are set forth in the appended claims. | 4y
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This invention relates to a sorting line for processing envelopes, particularly for photographic laboratories.
BACKGROUND OF THE INVENTION
As photography develops there is an increasing availability of photographic laboratories which develop and print films originating from photographic shops. In practice the amateur or professional photographer hands the exposed films to the shop for developing and printing, and the shop transmits them to the photographic laboratory after inserting them into envelopes known as "processing envelopes".
Here, after extraction from the processing envelopes, they are developed and printed, and after treatment the negatives and prints are reinserted into the processing envelope to be returned to the shop, which then consigns them to the customer.
The complete operational cycle undergone in the photographic laboratory, i.e. the cycle commencing with the reception of the processing envelopes and terminating with the re-delivery of the processing envelopes, has as its final stage the sorting of these envelopes originating from the finishing stage into suitable bags or boxes or other containers corresponding to the different destinations of the envelopes themselves. These destinations can be individual shops if these involve large quantities of processing envelopes, or can be a group of shops where smaller quantities of processing envelopes are concerned.
In either case there is the problem of effecting this sorting in the most reliable, fast and simple manner possible. These requirements can clearly be satisfied to a greater degree the finer the distribution, i.e. the narrower the division of the processing envelopes into their different destinations.
However this requirement, which could be totally satisfied if it were possible to reserve one container for each shop, i.e. for each destination, is however opposed by containing the space requirements of a sorting line within acceptable limits, these requirements being greater the narrower the division into the various destinations. For example, a sorting line for processing envelopes is known comprising essentially an endless mobile chain, to which bottom-openable pockets are applied. Below the path of the pockets there are provided a plurality of bags for collecting the envelopes, to correspond to the different customers or to the particular customer groupings. The processing envelopes originating from the finishing station are inserted automatically into the successive pockets, which then cause them to fall into the bag corresponding to the particular envelope destination, this destination having been previously read from the envelope and used, by means of the reading signal, to cause the various pockets to open when these are positioned exactly above the corresponding bag.
However this known processing envelope sorting line has the drawback of a large plan area and an unsatisfactory limit to the maximum number of bags or boxes which the plant can serve.
A further drawback is that the need to group together several destinations during the sorting stage requires a subsequent sorting operation, which is generally effected manually with the aid of a pigeon hole system, and consequently requires further space due to the presence of the pigeon hole system, plus manual operations which slow down and thus increase the cost of the whole sorting operation.
SUMMARY OF THE INVENTION
All these drawbacks are obviated according to the invention by a sorting line for processing envelopes, characterised by comprising at least one endless conveyor for a plurality of boxes provided with a base which opens under a command correlated with the position of said boxes along their path, and a plurality of compartments arranged on several levels in a position below said endless conveyor and provided with upperly open communication channels which emerge in positions corresponding with the different positions in which the base of said boxes opens.
A preferred embodiment of the present invention is further described hereinafter with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a general schematic perspective view of a sorting line according to the invention;
FIG. 2 is a plan view thereof to a reduced scale;
FIGS. 3 to 9 are plan views of further possible plant configurations;
FIG. 10 is an enlarged detailed plan view of the member for conveying the boxes along a line branch;
FIG. 11 is a vertical section on the line XI--IX of FIG. 10;
FIG. 12 is a detailed schematic perspective view of the connection region between the feeder and the sorting line; and
FIG. 13 is a detailed perspective view of the connection region between two line branches.
DETAILED DESCRIPTION OF THE INVENTION
As can be seen from the figures, the line according to the invention comprises essentially a main leg indicated overally by 2, and a plurality of branch legs arranged perpendicularly to the main leg and indicated overally by 4. The line also comprises a feeder 6 which as in the case of the legs 2 and 4 is described in detail hereinafter.
Both the main leg 2 and the branch legs 4 comprise, on a frame 8, an endless chain 10 extending horizontally between two end sprockets 12, one of which is associated with a conventional electric motor (not shown) for its movement.
To the links of the chain 10 there are fixed a plurality of upperly open parallelepiped boxes 16,16' having their side walls slightly converging downwards and their base 18 formed in the manner of a trapdoor, i.e. hinged along one side to the lower edge of a side wall so as to lie substantially vertical by gravity if not otherwise retained, and so lowerly open the corresponding box. The box 16,16', which is projectingly fixed to the corresponding link of the chain 10, is provided lowerly with a roller of vertical axis, which during the horizontal movement of the box rests against the vertical wall 22 of a section bar forming part of the frame 8.
A further roller 24,24' of horizontal axis is applied to each box 16,16' on the side opposite that which is hinged to the side wall of the box, to run along a horizontal guide 26,26' consisting of a plurality of segments 28 placed one behind the other. The position of the guide 26,26' is such that when the roller 24,24' rests against it, the base 18,18' of the corresponding box 16,16' lies horizontal (box closed). In addition, each segment 28 is connected to an electromagnet 30 which when powered causes it to move rearwards, so that said roller 24,24' no longer rests against it.
The plane in which the boxes 16 of the main leg 2 move is higher than the plane in which the boxes 16' of the branch legs 4 move, and more specifically the lowest level reached by the base 18 of the boxes 16 of the main leg 2 when said base is open is just higher than the level of the upper opening of the boxes 16' of each branch leg 4. In addition the position of each branch leg 4 compared with the main leg 2 is such that the position assumed by each box of this latter at an end position, i.e. when said box 16' lies exactly in the longitudinal middle plane through said branch leg 4, is exactly below the position of a box 16 of the main leg 2 (see FIG. 13).
In a position below the main leg 2 and branch legs 4 there are provided a plurality of cabinets 32,32' which extend horizontally following the horizontal extension of the main and branch legs and also vertically, to define a series of superimposed compartments 34,34'. More specifically, each cabinet 32,32' is divided horizontally into base modules 36,36' each formed of a plurality of superimposed compartments 34,34' (four on the drawing), associated with channels 38,38' which open upperly in a position exactly below the path of the corresponding boxes 16,16'. For the purpose of coordinating the various operating stages, the position of the upper opening of each channel 38,38' corresponds with the position of the mobile segments 28 of the corresponding horizontal guide 26,26', so that, as will be apparent hereinafter, when the base 18,18' of each box 16,16' opens, the processing envelope 46 contained in it exactly enters a channel 38,38'.
Again for the reasons which will be apparent hereinafter, those base modules of the cabinet 32 lying below the main leg 2 are provided only at those portions of said leg which are not involved with branch legs 4, and thus in practice it can happen that only the branch legs 4 are provide with underlying cabinets 32,32'. In the example shown in FIG. 1 only one branch leg 4 is associated with the main leg 2, and thus both these are provided with an underlying cabinet 32,32'. It is however apparent that if further branch legs are provided parallel to and side by side with the branch leg 4, the main leg 2 would be without an underlying cabinet, or at the most could be provided with cabinet portions only in the spaces between adjacent branch legs.
Each compartment 34,34' of each cabinet 32,32', which is open frontally for accessibility reasons, houses a removable container, which according to the dimension of the compartment can be either a bag 40 or a box 42.
In addition in proximity to the lower part of each channel 38,38' there is provided an optical sensor 44 the purpose of which is to sense both that correct passage of the processing envelope 46 has occured, as will be apparent hereinafter, and that the removable container placed in the corresponding compartment 34,34' has been filled.
The feeder 6 is situated at one end of the main leg 2. It is located downstream of a conventional manual or automatic feed line indicated overally by 48 and comprises a tray elevator 50 which for a certain distance runs parallel to and at the same speed as a belt conveyor 52. More specifically, the belt conveyor 52 runs parallel to the interior of the tray elevator 50 for the entire vertical lifting distance plus a subsequent horizontal distance which terminates at the longitudinal middle plane through the main leg 2, exactly in a position above the box 16 which is passing along that plane.
The tray elevator 50 and belt conveyor 52 are driven by a single electric motor, synchronized with the electric motors of the chains 10, so as to ensure that when a box 16' of the branch leg 4 is exactly in the longitudinal middle plane of the branch leg itself, there is a box 16 of the main leg 2 exactly above it. In addition the various electromagnets 30 which operate the segments 28 of the horizontal guides 26,26' are connected to a computer (not shown) which controls the entire sorting line.
The operation of the described sorting line is as follows: the already filled processing envelopes 46 reach the feed leg 48 one by one, where they undergo the conventional operations including the reading of the envelope identification data, the printing of a self-adhesive label and the application of this to the envelope. The identification data on the processing envelope, which also include data identifying its final destination, are generally contained in a number 54 written in bar code on the envelope.
Each envelope 46 is then fed between the trays of the elevator 50 and is raised thereby. When it reaches the upper end of the ascending vertical path and commences the horizonal path, it rests lowerly on the conveyor belts 52, which advance synchronously with the trays 50.
On reaching the front end of said belt conveyor 52, this no longer offers any support and the processing envelope 46 falls into a box 16 of the main leg 2, which by virtue of the synchronization between the movement of the tray elevator 50 and the movement of the chain 10 of said main leg 2, is correctly positioned to receive it.
The envelope 46 thus inserted into the box 16 of the main leg 2 advances along this latter. Assuming that the destination compartment 34' pertains to the branch leg 4, when the box 16 comes into proximity with that particular branch leg, a command is fed by the computer, which had previously memorized the identification data of that envelope and the identification data of the destination compartment, to cause the corresponding electromagnet 30 to retract the segment 28 associated with it, and consequently interrupt the horizontal guide 26 of the main leg 2 on the middle plane of the branch leg 4.
Consequently when the roller 24 of the box 16 reaches this gap, it loses its support and allows the base 18 to open by gravity, so that the processing envelope 46 (see FIG. 13) falls onto the underlying box 16' of the branch leg 4, which is in an assured correct position because of the synchronization between the movements of the chains 10 of the two legs 2 and 4.
When the envelope 46 has entered the box 16' of the branch leg 4, it is carried by this box to the upper opening of that channel 38 corresponding to the destination compartment 34'. Here a command fed to the electromagnet 30 of that segment 28 of the guide 26a of this branch leg 4 which corresponds to that particular channel 38' causes the base 18' of the box 16' to open and allow the processing envelope 46 to fall into said channel, at the lower end of which there has previously been placed a bag 40 or box 42.
After the box 16 of the main leg 2 or 16' of the branch leg 4 has deposited the processing envelope 46 in the box 16' of the branch leg 4 or in the channel 38' respectively, it proceeds on its path until the end of the straight portion of the respective leg, where there is provided an inclined surface (not shown) against which the roller 24,26' rests to again close the base 18,18' of the box and arrange it to receive a new processing envelope.
If the destination compartment 34 for the processing envelope 46 pertains not to the cabinet 32' of a branch leg 4 but to the cabinet 32 of the main leg 2, there will obviously be a direct transfer of the envelope 46 from the box 16 of the main leg 2 to the channel 38 of that compartment 34.
Should the opening of the base 18,18' of a box 16,16' be impeded or should a processing envelope 46 become jammed during its travel along the channel 38,38', the lack of sensing by the sensor 44 results in the emission of an alarm signal to allow the supervising personnel to investigate. An analogous signal is also emitted when the container 40 or 42 is nearly full to enable the supervising personnel to replace this container with an empty one.
From the aforegoing it is apparent that the sorting line according to the invention is considerably more advantageous than conventional lines, and in particular:
it comprises a large number of installed compartments; in practice for a surface area of about 140 m 2 , it is possible to install more than 1200 compartments against the approximately 500 compartments currently installable for a similar area;
it provides very high line flexibility, because of the possibility of covering any shape and size of surface;
it can be installed in an existing line with modifications and extensions of any kind and size;
it enables the entire sorting system to be totally automated, thus eliminating any manual redistribution work and also eliminating the manual sorting pigeon hole systems and the inconvenience of the space requirement and limited operability connected with them;
it provides complete protection for the processing envelopes as these are practically subjected to no handling during sorting;
it is of very safe and reliable operation and of low power consumption, being based on the simple horizontal movement of chains, electromagnetic ON-OFF controls and opening by gravity;
it allows the capacity of each compartment to be chosen and hence the line to be adapted to the different volume requirements of the various customers;
it enables each compartment to be equipped with a space for professional material and specifically for other-format prints, or publicity material, and for stamps etc. for the subsequent despatch. | 4y
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RELATED APPLICATIONS
This application is a National Stage of International Application No. PCT/JP2006/322321, filed Nov. 1, 2006, which is based on Japanese Patent Application No. 2005-320364, the entire contents of which is incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to a rack and pinion type steering device for a vehicle and a method of manufacturing the steering device.
BACKGROUND ART
The rack and pinion type steering device for the vehicle is so designed as to transmit the rotation of a pinion to a rack that is meshed with the pinion to move a tie rod that is fitted to an end portion of the rack, and transmit the rotation to a steering unit that controls the direction of the tire wheels.
The rack and pinion type steering device of this type includes a rack guide that presses the back surface of a rack shaft in a meshing direction by the aid of an elastic body such as a spring so that the pinion and the rack are appropriately meshed with each other.
Also, the rack guide is of a slide type in which the rack shaft and the rack guide are brought in slide contact with each other, and of a rolling type in which the rack shaft is supported by a roller. The rolling type is so configured as to bear a pin that supports the roller by a pin insertion groove that is defined in a rack guide holder (refer to Japanese Laid Open Patent Publication No. 2004-034829).
FIG. 5 is a cross-sectional view for explaining an example of the configuration of a rack and pinion type steering device 100 having the above conventional rolling type rack guide, FIG. 6( a ) is a partially cross-sectional view taken along a line A-A, FIG. 6( b ) is a cross-sectional view taken along a line B-B of FIG. 5 from which a housing is omitted.
A rack and pinion type steering device 100 is so configured as to arrange a pinion shaft 104 and a rack shaft 105 in the interior of a housing 101 . The pinion shaft 104 is rotationally supported by a ball bearing 102 and a needle bearing 103 . The rack shaft 105 is so arranged as to be movable in the axial direction by the aid of a rack bush not shown. An end of the rack shaft 105 is coupled with a tie rod having a link unit that changes the direction of the tire wheels through a ball joint. A rack tooth 105 a of the rack shaft 105 is meshed with a pinion tooth 104 a of the pinion that is integrally formed with the above pinion shaft 104 .
Further, a rack guide 106 is disposed at an opposite side of the pinion shaft 104 with respect to the rack shaft 105 in the interior of the housing 101 . The rack guide 106 is so configured as to press the rack shaft 105 from the back surface to appropriately maintain a meshing state of the pinion tooth 104 a with the rack tooth 105 a.
The rack guide 106 is made up of a rack guide holder 107 that is totally formed in a substantially cylindrical shape, a pin 108 that is arranged in a pin support hole 107 a which is defined in an inner space of the rack guide holder 107 in a direction orthogonal to the axial direction of the rack shaft 105 , and a roller 110 having a needle bearing 108 pressed into a center portion thereof and having an outer peripheral surface formed in a hand drum shape.
The roller 110 is installed on the pin 108 and rotationally disposed in the inner space of the rack guide holder 107 . The outer peripheral surface of the hand drum shape of the roller 110 is brought in rolling contact with the back surface of the rack shaft 105 (a surface at an opposite side of the meshed surface) so as to press the rack shaft 105 toward the meshed surface.
The housing 101 is equipped with a rack guide portion 111 having a cylindrical aperture that guides the rack guide holder 107 , and the outer peripheral surface of the rack guide holder 107 is fitted with the rack guide portion 111 . Also, a screw is formed in the inner surface of the rack guide portion 111 on a lower side (on an opposite side of the rack shaft 105 ) of the rack guide portion 111 of the housing 101 , so as to be meshed with an adjustment screw 112 .
The adjustment screw 112 is formed of a cylindrical member having a bottom. The adjustment screw 112 is so configured as to be meshed with the rack guide portion 111 , and press the rack guide holder 107 toward the rack shaft 105 through a disc spring 113 interposed between the adjustment screw 112 and the rack guide holder 107 . The screwing amount of the adjustment screw 112 is so adjusted as to appropriately adjust the meshing state of the rack tooth 105 a with the pinion tooth 104 a . The rack guide holder 107 can be displaced by the amount of elastic deformation of the disc spring 113 .
The conventional rack guide described with reference to FIGS. 5 , 6 ( a ), and 6 ( b ) suffers from the problems described below. That is, FIG. 7 is a diagram for explaining the cross-sectional configuration of the outer peripheral surface of the hand drum shape of the conventional roller 110 . In the conventional rack guide, as shown in FIG. 7 , the cross-sectional configuration of the hand drum shaped outer peripheral surface of the roller 110 is made up of curved surfaces R 1 and R 2 (R 1 can be equal to R 2 ) consisting of two circular arcs having the radius of curvature larger than the radius of curvature RR of the outer peripheral surface of the rack shaft 105 . Therefore, the hand drum shaped outer peripheral surface of the roller 110 and the outer peripheral surface of the rack shaft 105 are brought in point contact with each other at two points A and B.
The reason is that the radius of curvatures R 1 and R 2 of the outer peripheral surface of the roller 110 and the radius of curvature RR of the outer peripheral surface of the rack shaft 105 cannot be manufactured in the entirely identical radius of curvature because of the tolerance (permissible error) in the manufacture.
However, when the roller 110 and the rack shaft 105 are brought in point contact with each other as described above, because an area of the contact portion is very small, an estrangement force that occurs when the pinion and the rack are meshed with each other is transmitted to the rack guide holder 107 . Then, the contact portion of the roller 110 with the rack shaft 105 becomes high surface pressure, and the contact portion is liable to be worn.
As the countermeasure against the wear of the contact portion, it is general to increase the hardness of the contact portion, and in the above structure, there is proposed that the rack shaft is made of high carbon steel, and the roller is made of high carbon chromium bearing steel, and the rack shaft and the roller are subjected to a heat treatment to increase the hardness.
However, even if the hardness of the roller and the rack shaft is increased, the contact portion is high surface pressure without any change, and the wear cannot be completely suppressed. Also, the roller is deformed in the heat treatment, and the fluctuation of the roller becomes large with respect to the rotation center. When the vibration exists in the roller, the amount of elastic deformation of the disc spring (refer to FIG. 5 ) changes by the fluctuation amount due to the phase (rotational angle position) of the roller. As a result, since the movable amount of the rack guide changes, the fluctuation of the roller must be prevented as much as possible. For that reason, after the roller has been subjected to the heat treatment, the outer surface of the roller is ground so as to eliminate the fluctuation. However, the costs increase because the grinding process is conducted.
As described above, even if the hardness of the roller and the rack shaft is increased, the wear of the contact portion cannot be completely eliminated although the costs increase. As a result, there occur disadvantages such as an increase in the amount of elastic deformation of the disc spring or an increase in the movable amount of the rack guide.
Also, in the rack and pinion type steering device, when the rack guide movable amount increases, gear rattle (rattle noise) occurs. For that reason, an increase in the excessive rack guide movable amount must be avoided.
An object of the present invention is to solve the above disadvantages, that is, to suppress the wear of the contact portion of the roller with the rack shaft, eliminate an increase in the excessive rack guide movable amount, and prevent the rattle noise from occurring.
DISCLOSURE OF THE INVENTION
According to the present invention, there is provided a rack and pinion type steering device having a rack guide that includes a rack guide holder which is disposed to be movable toward a meshing direction of a rack and a pinion, and has a pin insertion groove formed in an interior thereof, and a roller which is rotatably installed on a pin which is disposed in the pin insertion groove of the rack guide holder, wherein an outer peripheral surface of the roller is formed around a rotating axis in a hand drum shape, and the outer peripheral surface of the hand drum shape has a configuration that comes in line contact with the outer peripheral surface on an opposite side of the meshed surface of the rack shaft and the pinion.
Then, the cross-sectional configuration of the hand drum shaped outer peripheral surface of the roller has a curvature identical with the curvature of the cross-sectional configuration of the outer peripheral surface on an opposite side of the meshed surface of the rack shaft with the pinion.
Also, according to the present invention, there is provided a method of manufacturing a rack and pinion type steering device having a rolling type rack guide which includes a rack guide holder that presses a back surface of a rack shaft toward a meshed surface of a rack and a pinion by the aid of a roller, and a roller having a hand drum shaped outer peripheral surface which is rotatably installed on a pin which is disposed in a pin insertion groove of the rack guide holder, wherein after the hand drum shaped outer peripheral surface of the roller is formed in a cross-sectional configuration of a curvature different from the curvature of the cross-sectional configuration of the outer peripheral surface on an opposite side of the meshed surface of the rack shaft with the pinion, the rack shaft is pressed toward the formed hand drum shaped outer peripheral surface to reciprocate the rack shaft in the axial direction so as to be plastically deformed while the roller rotates, and the hand drum shaped outer peripheral surface of the roller is formed in a configuration that comes in line contact with the outer peripheral surface on the opposite side of the meshed surface of the rack shaft.
In this case, it is possible that after the roller is formed in the hand drum shaped outer peripheral surface of a cross-sectional configuration having a curvature larger than the curvature of the cross-sectional configuration of the outer peripheral surface on an opposite side of the meshed surface of the rack shaft with the pinion, a surface hardening treatment is conducted, and the hand drum shaped outer peripheral surface is then plastically deformed into a configuration that comes in line contact with the outer peripheral surface on the opposite side of the meshed surface of the rack shaft.
In this case, it is possible that after the roller is formed in the hand drum shaped outer peripheral surface of a cross-sectional configuration having a curvature smaller than the curvature of the cross-sectional configuration of the outer peripheral surface on an opposite side of the meshed surface of the rack shaft with the pinion, a surface hardening treatment is conducted, and the hand drum shaped outer peripheral surface is then plastically deformed into a configuration that comes in line contact with the outer peripheral surface on the opposite side of the meshed surface of the rack shaft.
Also, it is possible that the plastic deformation of the hand drum shaped outer peripheral surface of the roller is conducted by pressing the rack guide toward the rack shaft.
Further, it is possible that the plastic deformation of the hand drum shaped outer peripheral surface of the roller is conducted by pressing the rack shaft toward the rack guide by applying a load to an end of the rack shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view for explaining the configuration of a rack and pinion type steering device having a rack guide of a rolling type according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a cross-sectional configuration of the outer peripheral surface of a roller that is plastically deformed.
FIG. 3 is a diagram for explaining a cross-sectional configuration of the outer peripheral surface of the roller which has not yet been plastically deformed according to a second embodiment.
FIG. 4 is a diagram for explaining a method of plastically deforming the outer peripheral surface of the roller according to a third embodiment.
FIG. 5 is a cross-sectional view for explaining an example of the configuration of a conventional rack and pinion type steering device having a rack guide of a rolling type.
FIG. 6( a ) is a cross-sectional view taken along a line A-A of FIG. 5 .
FIG. 6( b ) is across-sectional view taken along a line B-B of FIG. 5 .
FIG. 7 is a diagram for explaining the cross-sectional configuration of the outer peripheral surface of the roller in the conventional art, and the cross-sectional configuration of the outer peripheral surface of the roller which has not yet been plastically deformed according to the first embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Here under, the preferred embodiments of the present invention will be described.
First Embodiment
FIG. 1 is a cross-sectional view for explaining the configuration of a rack and pinion type steering device 10 having a rack guide of a rolling type according to a first embodiment of the present invention.
The rack and pinion type steering device 10 is so configured as to arrange a pinion shaft 14 and a rack shaft 15 in the interior of a housing 11 . The pinion shaft 14 is rotationally supported by a ball bearing 12 and a needle bearing 13 . The rack shaft 15 is so arranged as to be movable in the axial direction by the aid of a rack bush not shown. An end of the rack shaft 15 is coupled with a tie rod having a link unit that changes the direction of the tire wheels through a ball joint not shown. A rack tooth 15 a of the rack shaft 15 is meshed with a pinion tooth 14 a of the pinion that is integrally formed with the above pinion shaft 14 .
Further, a rack guide 16 is disposed at an opposite side of the pinion shaft 14 with respect to the rack shaft 15 in the interior of the housing 11 . The rack guide 16 is so configured as to press the rack shaft 15 from the back surface to appropriately maintain a meshing state of the pinion tooth 14 a with the rack tooth 15 a.
The rack guide 16 is made up of a rack guide holder 21 that is totally formed in a substantially cylindrical shape, a pin 22 that is arranged in a pin support hole 21 a which is defined in an inner space of the rack guide holder 21 in a direction orthogonal to the axial direction of the rack shaft 15 , and a roller 24 having a needle bearing 23 pressed into a center portion thereof and having an outer peripheral surface formed in a hand drum shape.
The roller 24 is installed on the pin 22 and rotationally disposed in the inner space of the rack guide holder 21 . The outer peripheral surface of the hand drum shape of the roller 24 is brought in rolling contact with the back surface of the rack shaft 15 (a surface at an opposite side of the meshed surface) so as to press the rack shaft 15 toward the meshed surface.
The housing 11 is equipped with a rack guide portion 11 a having a cylindrical aperture that guides the rack guide holder 21 , and the outer peripheral surface of the rack guide holder 21 is fitted with the rack guide portion 11 a . Also, a screw is formed in the inner surface of the rack guide portion 11 a on a lower side (on an opposite side of the rack shaft 15 ) of the rack guide portion 11 a of the housing 11 , so as to be meshed with an adjustment screw 25 .
The adjustment screw 25 is formed of a cylindrical member having a bottom. The adjustment screw 25 is so configured as to be meshed with the rack guide portion 11 a , and press the rack guide holder 21 toward the rack shaft 15 through a disc spring 26 interposed between the adjustment screw 25 and the rack guide holder 21 . The screwing amount of the adjustment screw 25 is so adjusted as to appropriately adjust the meshing state of the rack tooth 15 a with the pinion tooth 14 a . The rack guide holder 21 can be displaced by the amount of the elastic deformation of the disc spring 26 .
A description will be given of the configuration of the outer peripheral surface of the roller 24 and a method of forming the outer peripheral portion. The cross-sectional configuration of the outer peripheral surface of the roller 24 is identical with the cross-sectional configuration of the outer peripheral surface of the roller 110 in the conventional art described with reference to FIG. 7 in advance. That is, the cross-sectional configuration of the outer peripheral surface of the roller 24 is made up of curved surfaces consisting of two circular arcs having the radius of curvatures R 1 and R 2 (R 1 can be equal to R 2 ) which are larger than the radius of curvature RR of the cross-sectional configuration of the outer peripheral surface of the rack shaft 15 .
A description will be given of a method of forming the outer peripheral surface of the roller 24 . First, the configuration of the outer peripheral surface of the roller 24 is formed into an outer peripheral surface having the above cross-sectional configuration, that is, a cross-sectional configuration that consists of two circulate arcs. The outer peripheral surface is surface hardened by known appropriate means.
Subsequently, the pinion shaft 14 , the rack shaft 15 , and the rack guide holder 21 are assembled in the interior of the housing 11 , and the adjustment screw 25 is fastened more than usual to supply an excessive load more than that originally supplied to the rack guide holder 21 .
The rack shaft 15 is reciprocated in the axial direction under a state where the excessive load more than that originally supplied is supplied to the rack guide holder 21 , thereby plastically deforming the outer peripheral surface of the roller 24 into the configuration of the outer peripheral surface of the rack shaft 15 so as to follow the outer peripheral surface of the rack shaft. The plastic deformation makes the cross-sectional configurations (radii R 1 and R 2 ) of the outer peripheral surface of the roller 24 coincide with the cross-sectional configuration (radius RR) of the outer peripheral surface of the rack shaft (R 1 =R 2 =RR) As a result, the outer peripheral surface of the roller 24 comes in line contact with the outer peripheral surface of the rack shaft with a high precision.
FIG. 2 is a diagram showing the cross-sectional configuration of the outer peripheral surface of the roller 24 that has been plastically deformed. The outer peripheral surface of the roller 24 and the outer peripheral surface of the rack shaft 15 come in line contact with each other in areas of portions C and D. A portion E is a groove that is defined in the roller 24 in advance.
The face hardening treatment of the outer peripheral surface of the above roller 24 is conducted by a method such as a known carburization quenching or a nitriding treatment. In this situation, it is desirable that the thickness of the hardened layer is about 0.1 to 0.6 mm, and it is undesirable that the hardened layer is too thick because plastic deformation is difficult.
According to the above configuration, the outer peripheral surface of the roller and the outer peripheral surface of the rack shaft come in line contact with each other, and the contact area increases, thereby making it possible to decrease the contact surface pressure. As a result, it is possible to suppress the wear of the contact surface, prevent an increase in the excessive rack guide movable amount, and prevent rattle noise from occurring.
Second Embodiment
A second embodiment is similar in the configuration to the rack and pinion type steering device 10 having the rack guide of the rolling type according to the first embodiment, and only the configuration of the outer peripheral surface of the roller 24 is different from that in the first embodiment. Accordingly, the configuration of the rack and pinion type steering device having the rack guide is omitted from the detailed description with FIG. 1 and its description, and only differences will be described.
FIG. 3 is a diagram for explaining a cross-sectional configuration of the outer peripheral surface of the roller which has not yet been plastically deformed according to a second embodiment. In the second embodiment, the cross-sectional configuration of the outer peripheral surface of the roller 24 is formed into a curved surface having a radius of curvature R 1 smaller than the radius of curvature RR which is the cross-sectional configuration of the outer peripheral surface of the rack shaft 15 . For that reason, the outer ring of the roller 24 and the outer peripheral surface of the rack shaft 15 come in contact with each other at only points A and B.
In the second embodiment, the configuration of the outer peripheral surface of the roller 24 is formed into the cross-sectional configuration shown in FIG. 3 , and the outer peripheral surface is face-hardened by known appropriate means.
Then, the pinion shaft 14 , the rack shaft 15 , and the rack guide holder 21 are assembled in the interior of the housing 11 , and the adjustment screw 13 is fastened more than usual to supply an excessive load more than that originally supplied to the rack guide holder 21 .
The rack shaft 15 is reciprocated in the axial direction under a state where the excessive load more than that originally supplied is supplied to the rack guide holder 21 , thereby plastically deforming the outer peripheral surface of the roller 24 into the configuration of the outer peripheral surface of the rack shaft 15 so as to follow the outer peripheral surface of the rack shaft. The plastic deformation makes the cross-sectional configurations (radius R 1 ) of the outer peripheral surface of the roller 24 coincide with the cross-sectional configuration (radius RR) of the outer peripheral surface of the rack shaft (R 1 =RR) As a result, the outer peripheral surface of the roller 24 comes in line contact with the outer peripheral surface of the rack shaft with a high precision.
Similarly, in the second embodiment, the cross-sectional configuration (radius R 1 ) of the outer peripheral surface of the roller 24 that has been plastically deformed is shown in FIG. 2 . The outer peripheral surface of the roller 24 and the outer peripheral surface of the rack shaft 15 come in line contact with each other in areas of portions C and D. A portion E is a groove that is defined in the roller 24 in advance.
The surface hardening treatment of the outer peripheral surface of the above roller 24 is conducted by a method such as a known carburization quenching or a nitriding treatment as in the first embodiment. It is desirable that the thickness of the hardened layer is about 0.1 to 0.6 mm, and it is undesirable that the hardened layer is too thick because plastic deformation is difficult.
Similarly, in the second embodiment, the contact area of the outer peripheral surface of the roller with the outer peripheral surface of the rack shaft increases, thereby making it possible to reduce the contact surface pressure. As a result, it is possible to suppress the wear of the contact surface, prevent an increase in the excessive rack guide movable amount, and prevent rattle noise from occurring.
Third Embodiment
A third embodiment is similar in the configuration to the rack and pinion type steering device 10 having the rack guide of the rolling type according to the first embodiment, and only a method of plastically deforming the configuration of the outer peripheral surface of the roller 24 is different from the methods of the first and second embodiments. Accordingly, the configuration of the rack and pinion type steering device having the rack guide is omitted from the detailed description with the first embodiment shown in FIG. 1 , and only differences will be described.
The cross-sectional configuration of the outer peripheral surface of the roller 24 which has not yet been plastically deformed according to the third embodiment is identical with the conventional cross-sectional configuration shown in FIG. 7 , and also identical with the configuration of the outer peripheral surface which has not yet been plastically deformed according to the first embodiment. That is, the cross-sectional configuration of the outer peripheral surface of the roller 11 is formed of a curved surface consisting of two circular arcs with curved surfaces R 1 and R 2 (R 1 can be equal to R 2 ) having the radius of curvatures larger than the radius of curvature RR which is the cross-sectional configuration of the outer peripheral surface of the rack shaft 15 . For that reason, the outer ring of the roller 24 and the outer peripheral surface of the rack shaft 15 come in contact with each other at only points A and B.
In the third embodiment, the configuration of the outer peripheral surface of the roller 24 is first formed into the cross-sectional configuration shown in FIG. 7 , and the outer peripheral surface is surface hardened by known appropriate means.
Then, as shown in FIG. 4 , a load F is applied to the end of the rack shaft 15 to press the rack shaft 15 toward the roller 24 within the rack guide holder 21 . Since FIG. 1 shows a state in which the rack shaft 15 is disposed perpendicularly to the paper surface, the end of the rack shaft 15 is disposed on a front side from the paper surface.
In FIG. 4 , a load is applied to a ball joint 31 that is a coupling portion of the end of the rack shaft 15 with the tie rod 30 . Alternatively, the load F can be applied directly to the end of rack shaft 15 . The significant matter resides in that the rack shaft 15 is pressed toward the roller 25 within the rack guide holder 21 .
The rack shaft 15 is reciprocated in the axial direction under a state where the excessive load more than that originally supplied is supplied to the rack guide holder 21 , thereby plastically deforming the outer peripheral surface of the roller 24 into the configuration of the outer peripheral surface of the rack shaft 15 so as to follow the outer peripheral surface of the rack shaft. The plastic deformation makes the cross-sectional configurations (radii R 1 and R 2 ) of the outer peripheral surface of the roller 24 coincide with the cross-sectional configuration (radius RR) of the outer peripheral surface of the rack shaft (R 1 =R 2 =RR). As a result, the outer peripheral surface of the roller 24 comes in line contact with the outer peripheral surface of the rack shaft with a high precision.
Similarly, in the third embodiment, the cross-sectional configuration (radius R 1 ) of the outer peripheral surface of the roller 24 that has been plastically deformed is shown in FIG. 2 . The outer peripheral surface of the roller 24 and the outer peripheral surface of the rack shaft 15 come in line contact with each other in areas of portions C and D. A portion E is a groove that is defined in the roller 24 in advance.
The surface hardening treatment of the outer peripheral surface of the above roller 24 is conducted by a method such as a known carburization quenching or a nitriding treatment as in the first and second embodiments. It is desirable that the thickness of the hardened layer is about 0.1 to 0.6 mm, and it is undesirable that the hardened layer is too thick because plastic deformation is difficult.
In the above third embodiment, the cross-sectional configuration of the outer peripheral surface of the roller 24 which has not yet been plastically deformed is described as the conventional cross-sectional configuration shown in FIG. 7 , and the cross-sectional configuration of the roller 24 according to the first embodiment which has not yet been plastically deformed shown in FIG. 7 . Alternatively, the cross-sectional configuration can be formed in the cross-sectional configuration of the roller 24 according to the second embodiment shown in FIG. 3 which has not yet been plastically deformed.
Similarly, in the third embodiment, the contact area of the outer peripheral surface of the roller with the outer peripheral surface of the rack shaft increases, thereby making it possible to reduce the contact surface pressure. As a result, it is possible to suppress the wear of the contact surface, prevent an increase in the excessive rack guide movable amount, and prevent rattle noise from occurring.
As has been described above, according to the rack and pinion type steering device of the present invention, the outer peripheral surface of the roller that is rotatably installed on the rack guide is formed around the rotating axis in the hand drum configuration. The outer peripheral surface of the hand drum shape has a configuration that comes in line contact with the outer peripheral surface on the opposite side of the meshed surface of the rack surface with the pinion. More specifically, the cross-sectional configuration of the hand drum shaped outer peripheral surface of the roller is formed with a curvature identical with the curvature of the cross-sectional configuration of the outer peripheral surface on the opposite side of the meshed surface of the rack shaft with the pinion.
With the above configuration, the contact area of the outer peripheral surface of the roller with the outer peripheral surface of the rack shaft increases, thereby making it possible to reduce the contact surface pressure. As a result, it is possible to suppress the wear of the contact surface, prevent an increase in the excessive rack guide movable amount, and prevent rattle from occurring.
Also, according to the method of manufacturing the rack and pinion type steering device of the present invention, after the roller that is rotatably installed on the rack guide is formed with the hand drum shaped outer peripheral surface having a curvature different from the curvature of the outer peripheral surface on an opposite side of the meshed surface of the rack shaft with the pinion, the rack shaft is reciprocated in the axial direction and plastically deformed while the rack shaft is pressed toward the hand drum shaped outer peripheral surface, and the hand drum shaped outer peripheral surface of the roller is formed in the configuration that comes in line contact with the outer peripheral surface of the rack shaft.
In the outer peripheral surface of the roller that has been manufactured by the manufacturing method, the hand drum shaped outer peripheral surface of the roller and the outer peripheral surface of the rack shaft come in line contact with each other with a high precision. With the above configuration, the contact area of the outer peripheral surface of the roller with the outer peripheral surface of the rack shaft increases, thereby making it possible to reduce the contact surface pressure. As a result, it is possible to suppress the wear of the contact surface, prevent an increase in the excessive rack guide movable amount, and prevent rattle from occurring.
Then, since the hand drum shaped outer peripheral surface of the roller is plastically deformed so as to follow the outer peripheral surface of the rack shaft, the outer peripheral surface of the roller can come in line contact with the outer peripheral surface of the rack shaft with a high precision without conducting a precise current work, and the treatment of the hand drum shaped outer peripheral surface of the roller can be easily conducted with a high precision.
INDUSTRIAL APPLICABILITY
In the rack and pinion type steering device having the rack guide which can prevent the rattle noise from occurring and the method of manufacturing the steering device, a contact state of the outer peripheral surface of the rack shaft with the outer peripheral surface of the roller of the rack guide holder changes from a point contact to a line contact to enlarge the contact area and reduce the contact surface pressure. With the above configuration, it is possible to prevent the wear of the contact surface, prevent an increase in the excessive rack guide movable amount, and prevent rattle noise from occurring. Also, the treatment of the hand drum shaped outer peripheral surface of the roller can be easily conducted with a high precision. | 4y
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[0001] This application claims the benefit of U.S. Provisional Application No. 60/947,135, filed on Jun. 29, 2007, the entire contents of which are incorporated herein by reference.
FIELD
[0002] A connector that fluidly connects a first fluid system to a second fluid system for performing processing operations, for example charging, evacuation and/or testing, on the second fluid system.
BACKGROUND
[0003] A connector is often used to connect an external fluid system, for example charging, evacuation and/or testing equipment, to a second fluid system, for example manufacturing, test, or processing equipment. Once the connection is made and any valves are opened, fluid can flow through the connector either into the second fluid system or from the second fluid system depending on the processing operation being performed.
[0004] Connectors are typically designed with one connection interface that enables the connector to be able to connect to the second fluid system in only one way. This means that a typical connector cannot be used to connect to fluid systems that require different connection interfaces on the connector.
[0005] Further, conventional connectors are provided with one actuator for actuating the connectors, for example a manual or pneumatic/hydraulic actuator. However, one actuator is not necessarily appropriate for every connection to be made. For example, with manual and pneumatic/hydraulic connector actuation, the connection forces are hard to control which may prevent use of those types of actuators when connecting to a delicate or fragile fluid system. Further, space constraints may limit or prevent use of certain type of actuators.
SUMMARY
[0006] A modular connector system is described that permits changes to the connector, for example changes in the type of connection interface that is used and/or changes in the type of actuator that is used to actuate the connector. By making parts of the connector changeable, the connector can be changed so as to be able to connect to different fluid systems. This eliminates the need to have separate connectors for different fluid systems.
[0007] In one embodiment, a modular connector system for connecting a first fluid system to a second fluid system includes a connector body having a connector end and an actuator end, and a plurality of connector units. Each connector unit includes a connection mechanism that detachably connects the respective connector unit to the connector end of the connector body. The connection mechanisms of the connector units connect the connector units to the connector end in the same manner, thereby allowing the different connector units to connect to the connector body.
[0008] The modular connector system can also include a plurality of actuator units, each of which includes a connection mechanism that detachably connects the respective actuator unit to the actuator end of the connector body. The connection mechanisms of the actuator units can connect the actuator units to the actuator end in the same manner thereby allowing the different actuator units to connect to the connector body.
[0009] Any type of detachable connection between the connector body and the connector units and/or actuator units can be used if found suitable. One form of detachable connection described herein comprises threads.
[0010] In an embodiment, the connector body includes a generally hollow sleeve having a connector end and an actuator end, with threads at the connector end that enable connection to a connector unit and threads at the actuator end that enable connection to an actuator unit. A piston is slidably disposed within the sleeve so that the piston and the sleeve can move relative to one another.
[0011] Each actuator unit can be comprised of an actuation mechanism, and a connection mechanism that detachably connects the respective actuator unit to an actuator end of a connector body. The connection mechanisms connect the actuator units to the actuator end in the same manner.
[0012] Each connector unit can comprise means for connecting to the fluid system, and a connection mechanism that detachably connects the respective connector unit to a connector end of a connector body. The connection mechanisms connect the connector units to the connector end in the same manner.
[0013] The modular connector system can also include a flexible drive to interconnect the connector body and a connector unit. The flexible drive can include an elongated, hollow flexible tube with a first end and a second end, a connection mechanism at the first end of the tube for detachably connecting the tube to the connector body, and a connection mechanism at the second end of the tube for detachably connecting the tube to the connector unit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Further details are explained below with the help of the examples illustrated in the attached drawings in which:
[0015] FIG. 1 is a top view of a modular connector in accordance with one exemplary embodiment.
[0016] FIG. 2 is a longitudinal cross-sectional view of the modular connector of FIG. 1 taken along line 2 - 2 .
[0017] FIG. 3 is a perspective view of a connector body used in the modular connector system.
[0018] FIG. 4 is a longitudinal cross-sectional view of the connector body.
[0019] FIG. 5 is a cross-sectional view of the portion contained in area 5 from FIG. 2 showing the connector unit in detail.
[0020] FIG. 6 is a cross-sectional view of the actuator unit from FIG. 2 .
[0021] FIGS. 7-12 illustrate alternative embodiments of connector units of the modular connector system.
[0022] FIGS. 13-16 illustrate alternative embodiments of actuator units of the modular connector system.
[0023] FIGS. 17-24 illustrate various embodiments of a flexible drive interconnecting the connector body and various connector units.
[0024] FIG. 25 illustrates an embodiment without an integrated actuator unit fixed to the connector.
DETAILED DESCRIPTION
[0025] A modular connector system is described that permits one or more parts of a connector to be changed to permit use of the connector with different fluid systems. As described herein, the connector system includes at least one connector body, a plurality of connector units that are each individually connectable to the connector body, a plurality of actuator units that are each individually connectable to the connector body, and optionally at least one flexible drive that is designed to interconnect the connector body to the connector units. However, alternative connector systems are possible, including those where the connector units can be changed but the actuator unit that is used is fixed, the actuator units can be changed but the connector unit that is used is fixed, the connector body can be changed but the connector unit and the actuator unit are fixed, and various other combinations.
[0026] In its simplest form, a modular connector that is produced from the modular connector system includes a connector body, an actuating means for actuating the modular connector, and a means to connect the modular connector to a fluid system for performing processing operations, for example charging, evacuation and/or testing, on the fluid system. The actuating means can be an actuator unit, for example an actuator unit described herein. The means to connect can be a connector unit, for example a connector unit described herein. In certain embodiments, the modular connector can include a flexible drive between the connector body and the means to connect.
[0027] With reference initially to FIG. 1 , an embodiment of a modular connector 10 is illustrated that can fluidly connect a first fluid system (not shown) to an interface 100 of a second fluid system for performing processing operations, for example charging, evacuation and/or testing, on the second fluid system. The first fluid system to which the modular connector 10 is attached can be, for example, a source of air or helium for testing. The second fluid system to which the modular connector 10 is intended to connect can be, for example, a fluid reservoir. However, the modular connector 10 can be used with other fluid systems in which a connector is used to fluidly connect a first fluid system to a second fluid system.
[0028] The modular connector 10 includes a connector body 12 , an actuating means in the form of an actuator unit 14 for actuating the connector, and a means to connect in the form of a connection unit 16 . With reference to FIG. 2 , the actuator unit 14 connects to the connector body 12 in a detachable manner to allow a different actuator unit to be connected to the connector body for actuating the connector 10 . Likewise, the connection unit 16 connects to the connector body 12 in a detachable manner to allow a different connection unit to be connected to the connector body for connecting to the interface 100 .
[0029] With reference to FIGS. 3 and 4 , the connector body 12 includes a generally hollow, tubular sleeve 20 having an externally threaded back or actuator end 22 and an externally threaded front or connector end 24 . The threads form means by which the actuator unit 14 and connection unit 16 connect to the connector body. The back end 22 and front end 24 of the sleeve 20 are both open. The sleeve 20 also includes an elongated slot 26 formed therethrough.
[0030] The connector body 12 also includes an actuation piston 30 that is slideably disposed within the sleeve 20 to permit relative sliding movement between the piston 30 and the inside surface of the sleeve 20 . The actuation piston 30 includes an internal axial passageway 60 extending through the front end thereof, and a radial passage 62 connected to the axial passageway 60 . As shown in FIGS. 1 and 2 , a threaded fitting 64 is threaded into the radial passage 62 and forms a means to connect to the first fluid system. The slot 26 in the sleeve 20 accommodates rearward and forward movements of the fitting 64 as the piston 30 moves axially, and the fitting 64 protruding through the slot 26 limits rotational movement of the piston 30 . Further, the rear of the piston 30 includes an internally threaded hollow portion 66 at the rear of the actuation piston 30 which engages with the actuator unit 14 in a manner discussed below.
[0031] Turning now to FIG. 5 , the connection unit 16 includes a tube 70 that is threaded within the axial passageway 60 of the piston and extends beyond the end of the sleeve 20 and the piston 30 . Due to the threaded engagement between the tube 70 and the piston 30 , axial movement of the piston 30 results in corresponding axial movement of the tube 70 . A seal 72 is provided to seal between the outer circumference of the tube 70 and the interior of the passageway 60 to prevent fluid leaks. The tube 70 includes an internal flow passage 74 that communicates with the rear of the passageway 60 and with the radial passage 62 to form a fluid flow passage between the tube 70 and the fitting 64 .
[0032] The connection unit 16 further includes a cap 80 that is threaded onto the threaded front end 24 of the sleeve 20 . The cap 80 includes a central opening 82 through which the tube 70 passes. At the point where the tube 70 extends past the cap 80 , the tube 70 includes a reduced diameter section 84 that extends to the front end of the tube 70 . A washer 86 is slid over the reduced diameter section 84 , followed by a tubular seal 88 , and another washer 90 . The washer 86 , the seal 88 and the washer 90 are retained on the tube 70 by a lock ring 92 .
[0033] Actuation of the piston 30 is achieved using the actuator unit 14 . With reference to FIG. 6 , the actuator unit 14 in this embodiment includes an actuation mechanism in the form of an electric actuator 34 , and a connection mechanism that detachably connects the actuator unit to the threaded end 22 of the connector body 12 .
[0034] The connection mechanism of the actuator unit 14 includes an internally threaded hexagonal nut 32 that can thread onto the back end 22 of the sleeve 20 of the connector body 12 . The electric actuator 34 in this embodiment takes the form of an electric motor having a drive shaft 36 connected to a suitable reduction mechanism 38 , for example a gear box, to increase torque. The electric motor can be connected to any suitable source of electricity, for example a 120V source or to one or more batteries. The reduction mechanism 38 is fixed to the nut 32 via a flange 40 that is integral with the nut 32 and screws 42 that extend through the flange 40 and into threaded receptacles on the reduction mechanism 38 . The electric motor is preferably a two-way motor to allow forward and reverse rotation of the drive shaft 36 .
[0035] The reduction mechanism 38 includes an output 44 that is fixed to a screw drive 46 for rotating the screw drive 46 . As shown in FIG. 2 , the screw drive 46 extends into the hollow portion 66 at the rear of the actuation piston 30 . A drive nut 48 is threaded onto the screw drive 46 . The exterior surface of the nut 48 is threaded and is screwed into the hollow portion 66 of the piston 30 . The nut 48 also includes a radial flange 52 on the rear end thereof that engages the rear of the piston 30 . When the actuator unit 14 is mounted in position, and when the screw drive 46 is rotated, the drive nut 48 is driven in a forward direction toward the connection mechanism 16 or driven in a rearward direction away from the connection mechanism 16 . Since the nut 48 is fixed to the piston 30 , the piston 30 moves with the nut 48 in either the forward or rearward direction.
[0036] As shown in FIG. 6 , thrust washers 54 are disposed on either side of a flange 56 at the rear of the screw drive 46 within the nut 32 . The thrust washers 54 prevent transfer of thrust to drive gears in the reduction mechanism 38 . In addition, a drive support washer 58 is provided between the flange 52 and the thrust washers 54 , disposed around the screw drive 46 within the nut 32 .
[0037] To achieve connection with the interface 100 , the projecting end of the tube 70 is inserted into the end of the interface 100 . The electric motor is then activated to rotate the screw drive 46 in the appropriate direction to cause the piston 30 to be actuated axially rearwardly. This retracts the tube 70 into the connector 10 , which causes the seal 88 to be compressed between the washers 86 , 90 , due to engagement between the washer 86 and the cap 80 . As the seal 88 is compressed, it expands in diameter, and seals against the inner diameter of the interface 100 . Processing can then occur through the connector 10 , with fluid being able to flow through the connector between the first and second fluid systems. Disconnection is achieved by activating the motor to actuate the piston 30 forwardly to release the compression on the seal 88 , returning the connection unit 16 to its original state.
[0038] When connected, the connection unit 16 in this embodiment seals with the fluid system interface 100 . There is no gripping ability provided by the connection unit 16 other than the friction of the seal 88 against the inner diameter of the fluid system interface.
[0039] Other connection units can be used with the modular connector system. Examples of alternative connection units are illustrated in FIGS. 7-12 in which the same reference numerals indicate elements that are similar to those described above.
[0040] In FIG. 7 , the connection unit 120 that seals and grips with the interface 100 is illustrated. The connection unit 120 is similar in construction and operation to the non-modular connection mechanism disclosed in U.S. Pat. No. 5,343,798 which is incorporated herein by reference in its entirety.
[0041] The unit 120 comprises a tube 122 that is threaded within the axial passageway of the piston 30 and extends beyond the end of the sleeve 20 and the piston 30 similar to the tube 70 . Due to the threaded engagement between the tube 122 and the piston 30 , axial movement of the piston 30 results in corresponding axial movement of the tube 122 . A seal 124 is provided to seal between the outer circumference of the tube 122 and the interior of the passageway to prevent fluid leaks. The tube 122 includes an internal flow passage 125 similar to the internal passage 74 .
[0042] The connection unit 120 further includes a cap 126 that is threaded onto the threaded front end 24 of the sleeve 20 . The cap 126 includes a central opening through which the tube 122 passes. A washer 128 is disposed over the tube, followed by a plurality of split collets 130 , a wedge 132 , and a seal 134 . The end of the tube 122 includes a flange 136 that retains the elements on the tube 122 . In addition, a resilient ring 138 surrounds the collets 130 to bias the collets to the position shown in FIG. 7 .
[0043] In use, the end of the connection unit 120 is inserted into the interface 100 . When the tube 122 is pulled rearwardly, the seal 134 is compressed and expands into engagement with the inner surface of the interface 100 to seal with the interface. In addition, the collets 130 are ramped outward by the wedge 132 into engagement with the inner diameter to grip with the interface 100 .
[0044] FIG. 8 shows a connection unit 140 that grips and seals with internal threads of an interface 102 . The connection unit 140 is similar in construction and operation to the non-modular connection mechanism disclosed in U.S. Pat. No. 5,788,290 which is incorporated herein by reference in its entirety. The sleeve 20 includes a modified piston 142 that is axially moveable in the sleeve 20 . The connection unit 140 includes a sleeve 144 that threads onto the threaded end 24 of the sleeve 20 . A hollow tube 146 is connected by threads to the piston 142 and extends into the sleeve 144 . A seal 148 is provided around the tube 146 to seal with the inner diameter of the sleeve 144 . The unit 140 also includes a plurality of split collets 150 that are pivotally connected to the end of the tube 146 , and a resilient ring 152 is disposed around the collets 150 to bias the collets. A pin 154 is disposed inside the collets 150 , and includes a tapered front end 156 . The pin 154 is supported by a cross-member 158 that is connected to the sleeve 144 via a retaining mechanism 159 . The front ends of the collets 150 are slideable on the outside of the pin 154 .
[0045] In FIG. 8 , the connection unit 140 is shown in its default, activated state. To activate the connection unit, the collets 150 are pushed outward over the end 156 of the pin 154 by the piston 142 and tube 146 . This permits the ends of the collets 150 to collapse under the bias of the ring 152 to a reduced diameter, allowing the end of the connection unit to be inserted into the interface 102 . The collets 150 are then retracted by pulling the piston and the tube toward the connector. As this occurs, the pin 154 causes the collets to expand outward back to the position shown in FIG. 8 so that the outside of the collets grip with the threads on the interface 102 . At the same time, the interface 102 seals against the end face of the sleeve 144 .
[0046] FIG. 9 shows a connection unit 160 that is designed to seal with the outer diameter of an interface 104 . The outer diameter can be smooth or it can have threads. There is no gripping ability provided by the connection unit 160 other than the friction of the seal against the outer diameter of the interface 104 .
[0047] The connection unit 160 includes a sleeve 162 that threads onto the threaded end 24 of the sleeve 20 . A seal 164 is disposed inside the sleeve 162 , sandwiched between two washers 166 , 168 . The washer 166 is movable axially within the sleeve 162 . In use, the interface 104 is inserted into the connection unit 160 . The piston 30 is advanced axially to push the washer 166 . This compresses and extrudes the seal 164 against the outer diameter of the interface 104 .
[0048] FIG. 10 shows a connection unit 180 that grips and seals with the interface 104 . The connection unit 180 is similar in construction and operation to the non-modular connection mechanism disclosed in U.S. Pat. No. 5,507,537 which is incorporated herein by reference in its entirety. The connection unit 180 includes a sleeve 182 that threads onto the threaded end 24 of the sleeve 20 . A hollow tube 184 is connected by threads to a modified piston 186 and extends partially into the sleeve 182 . A seal 188 is disposed inside the sleeve 182 , sandwiched between the end of the tube 184 and a washer 190 . A plurality of split collets 192 are disposed inside the front end of the sleeve 182 , with outer surfaces 194 of the collets 192 being sloped. A wear ring 196 is disposed between the outer surface of the collets 192 and the inner surface of the sleeve 182 so as to reduce the wear on the collets and the sleeve.
[0049] In use, the interface 104 is inserted into the connection unit 180 . The piston 186 is advanced axially to push against the seal 188 . This compresses and extrudes the seal 188 against the outer diameter of the interface 104 . At the same time, the collets 192 are ramped inward onto the outer diameter to grip the interface 104 .
[0050] FIGS. 11A-E show a connection unit 200 that is configured to seal with an interface 106 and to grip onto the interface 106 which is externally threaded or includes another feature that can be used for gripping, for example a bead, barb, bump, etc.
[0051] With reference to FIG. 11A , which shows the connection unit 200 in a default position, the connection unit 200 includes a sleeve 202 , and a lock ring 204 is threaded onto the threaded end 24 of the sleeve 20 . The lock ring 204 is disposed between a shoulder 206 on the sleeve 202 and a retainer 208 secured to the rear of the sleeve. A hollow tube 210 is threaded into a modified piston 212 and extends into the sleeve 202 . A plurality of collets 214 are pivotally secured to the end of the tube 210 , and a resilient biasing member 216 ( FIG. 11B ), for example a o-ring, biases the collets outward.
[0052] In addition, a sealing piston 218 is disposed inside the end of the tube 210 and inside the collets 214 . A main seal 220 is secured to the end of the piston 218 for sealing engagement with the interface 106 . Further, a plurality of push pins 222 extend through the end of the tube 210 and are engaged with the rear of the piston 218 and the end 24 of the sleeve 20 .
[0053] FIG. 11B shows the connection unit 200 in an open position, with the front ends of the collets 214 advanced axially by the piston 212 from the front end of the sleeve 202 which remains stationary with the sleeve 20 . The biasing force provided by the biasing member 216 causes the collets 214 to pivot open to facilitate insertion of the interface 106 . In addition, the front end of the tube 210 advances relative to the pins 222 to a position adjacent the rear side of the piston 218 . This permits the interface 106 to be inserted a maximum distance into the connection unit 200 .
[0054] FIG. 11C illustrates the start of connection. The interface 106 is inserted up to the main seal 220 and the piston 212 starting to be pulled back into the connector. The interior of the collets 214 are threaded. As a result, during connection as the collets close over the threads on the interface 106 , the threads may not exactly align. This can cause the interface 106 to back off the seal 220 slightly, for example up to ½ a thread, to match threads. The push pins 222 do not provide any function during the start of connection.
[0055] FIG. 11D illustrates the connector in mid connection. The piston 212 continues to draw the tube 210 , collets 214 , interface 106 and the sealing piston 218 into the sleeve 202 and the sleeve 20 . When the push pins 222 contact the end 24 of the sleeve 20 , the movement of the sealing piston 218 is stopped.
[0056] FIG. 11E illustrates the connector at full connection. As connection continues between FIGS. 11D and 11E , the push pins 222 continue to stop movement of the sealing piston 218 . As the interface 106 continues to be drawn into the connector, the interface 106 seals tightly against the main seal 220 . A seal 224 is provided that seals between the sealing piston 218 and the interior of the tube 210 . The seal 224 of the sealing piston 218 provides a larger sealing diameter than the main seal 220 so when under pressure, the sealing piston will generate a greater seal against the interface 106 .
[0057] FIG. 12 shows a connection unit 230 that grips and seals with an interface 108 . The connection unit 230 is similar in construction and operation to the non-modular connection mechanism disclosed in U.S. patent application Ser. No. 11/671,747 which is incorporated herein by reference in its entirety. The connection unit 230 has a semi-cylindrical nest 232 that includes a flange 234 that is configured to grip over a thread or another feature on the interface 108 . The nest 232 is threaded onto the threaded end 24 of the sleeve 20 . A seal 236 is disposed at the end of a piston 238 configured to seal with an internal diameter of the interface 108 .
[0058] In use, the interface 108 is inserted into the nest 232 so that the flange 234 grips over the threads or other feature on the interface. The piston 238 is then actuated forward into the interface 108 so that the seal 236 seals against the inner diameter of the interface 108 .
[0059] Connection units other than those described and illustrated herein can be used, provided they are found suitable for modularity.
[0060] As should be apparent, the connector units described above share a common connection mechanism, for example threads, that detachably connects the respective connector unit to the connector end of the connector body and connect the connector units to the connector end in the same manner.
[0061] To further enhance modularity, other actuator units can be used with the modular connector system. Examples of alternative actuator units are illustrated in FIGS. 13-16 in which the same reference numerals indicate elements that are similar to those described above.
[0062] FIGS. 13 and 14 provide a top view and a cross-sectional side view, respectively, of a manually activated actuator unit 300 shown connected to the back end 22 of the connector body 12 .
[0063] The actuator unit 300 includes an internally threaded hexagonal nut 302 that can thread onto the back end 22 of the sleeve 20 of the connector body 12 . The rear end of the nut 302 is slotted and a temporary force squeeze handle 304 is pivotally attached to the nut 302 by a pin 306 for providing a temporary compression motion. A piston 308 is threaded into the hollow portion 66 of the actuation piston 30 to fix the piston 308 to the piston 30 . The rear end of the piston 308 is engaged with the squeeze handle 304 .
[0064] When the squeeze handle 304 is squeezed in the direction of the arrow, the piston 308 and piston 30 are pushed forward to actuate the connector unit. When the handle 304 is released, the pistons 30 , 308 are biased by a suitable biasing means, for example a coil spring 310 , back to their position shown and the handle 304 returned to its original position.
[0065] FIG. 15 is a cross-sectional side view of a manually activated actuator unit 320 shown connected to the back end 22 of the connector body 12 which is only partially illustrated. The actuator unit 320 includes an internally threaded hexagonal nut 322 that can thread onto the back end 22 of the sleeve 20 of the connector body 12 . The rear end of the nut 322 is slotted and a flip handle 324 is pivotally attached to the nut 322 by a pin 326 . A piston 328 is threaded into the hollow portion of the actuation piston 30 to fix the piston 328 to the piston 30 . The rear end of the piston 328 is engaged with the flip handle 324 .
[0066] The flip handle 324 provides a constant compression force. FIG. 15 illustrates the deactivated or default position. When the handle 324 is rotated up or down, the piston 328 and the piston 30 are pushed forward to actuate the connector unit. When the handle 324 is rotated back to the position shown in FIG. 15 , the pistons 30 , 328 are biased by a suitable biasing means, for example a coil spring acting between the connector body 12 and the piston 30 , back to their position.
[0067] FIG. 16 is a cross-sectional side view of a pneumatic/hydraulic activated actuator unit 330 shown connected to the back end 22 of the connector body 12 which is only partially illustrated. The actuator unit 330 includes an internally threaded hexagonal nut 332 that can thread onto the back end 22 of the sleeve 20 of the connector body 12 . The nut 332 includes a fluid port 334 for pneumatic/hydraulic fluid. An o-ring 336 is disposed around a modified piston 338 that functions similarly to the piston 30 . The piston 338 has a circumferential channel 340 that receives the o-ring 336 .
[0068] In use, pressurized fluid, for example air or hydraulic fluid, is introduced through the port 334 and acts on the rear of the piston 338 . This pushes the piston 338 to actuate the connection unit. The force applied to the piston 338 can be a constant force if a constant fluid pressure is applied, or momentary if the fluid pressure is reduced. When air is used as the pressurized fluid, a spring may be used to bias the piston 338 back to the deactivated position. When hydraulic fluid is used, a biasing spring can be used to bias the piston back to the deactivated position, or withdrawal of the hydraulic fluid can cause the piston to pull back due to suction.
[0069] In certain case, the modular connector is used in tight spaces that make it difficult for both the connection unit and the actuator unit to be located in that space. Therefore, a flexible drive, examples of which are illustrated in FIGS. 17-24 , can be provided between the connector body and the connection unit.
[0070] FIG. 17 illustrates a flexible drive 400 between the connector body 12 and the actuation unit 16 illustrated in FIG. 5 . The flexible drive 400 includes a flexible external sleeve 402 having a cap 404 at one end that is threaded onto the front end 24 of the sleeve 20 . The opposite end 406 of the sleeve 402 is externally threaded and the cap 80 of the connection unit 16 is threaded onto the end 406 . The sleeve 402 can be made of a suitable flexible material, for example an elastomer.
[0071] A flexible, hollow shaft 410 is disposed inside the sleeve 402 . One end 412 of the shaft 410 is fixed to the piston 30 by threads, while the other end 414 of the shaft 410 is fixed to the tube 70 of the connection unit 16 . The shaft 410 includes a flow passage 416 to allow fluid to flow therethrough from the connection unit 16 to the connector body 12 . The shaft 410 is movable relative to the sleeve 402 to enable the shaft 410 to be pushed or pulled by the piston 30 to actuate the connection unit 16 . For example, when the piston 30 is actuated backward, the piston 30 pulls the shaft 410 backward, which retracts the tube 70 to actuate the connection unit 16 as described above.
[0072] FIG. 18 illustrates a flexible drive 430 similar in construction and function to the flexible drive 400 . One end of the drive 430 is connected to the connector body 12 in the same manner as the flexible drive 400 , while the opposite end is connected to the connection unit 120 illustrated in FIG. 7 . The drive 430 includes a flexible external sleeve 432 and a hollow, flexible shaft 434 movable inside the sleeve 432 , with the shaft 434 defining a flow passage 436 for fluid.
[0073] The flexible drives in FIGS. 17 and 18 can be used with any connection unit, including any connection unit described herein, which is activated by pushing or pulling of the shaft.
[0074] FIG. 19 illustrates a flexible drive 450 that utilizes hydraulic actuation. The flexible drive 450 is connected between the connector body 12 and the connection unit 140 illustrated in FIG. 8 . The flexible drive 450 includes a flexible external sleeve 452 having a cap 454 at one end that is threaded onto the front end 24 of the sleeve 20 . The opposite end 456 of the sleeve 452 is externally threaded and the sleeve 144 of the connection unit 140 is threaded onto the end 456 .
[0075] A flexible, hollow shaft 460 is disposed inside the sleeve 452 . One end 462 of the shaft 460 is disposed inside the piston 30 , while the other end 464 of the shaft 460 is fixed to the tube 146 of the connection unit 140 . The end 464 of the shaft 460 is formed into a piston 466 that is fixed to the tube 146 and is slideable within the end 456 of the sleeve 452 . O-rings 468 , 470 are provided to seal between the tube 146 and the piston 466 , and between the piston 466 and the sleeve 452 , respectively. The shaft 460 includes a flow passage 472 to allow fluid to flow therethrough between the connection unit 140 and the connector body 12 . In addition, a space 474 is provided between the sleeve 452 and the shaft 460 for hydraulic fluid
[0076] In addition, the front end of the piston 30 is modified with an exterior channel to receive an o-ring 476 for sealing with the interior of the sleeve 20 , and an interior channel 478 to receive an o-ring for sealing with the exterior of the end 462 . Thus, an enclosed hydraulic chamber is defined between the front end of the piston 30 , the space 474 , and the rear end 480 of the piston 466 .
[0077] When the piston 30 is actuated in a forward direction, the volume of the hydraulic chamber is reduced which increases the pressure of the hydraulic fluid. The fluid then pushes on the rear end 480 of the piston 466 , which actuates the tube 146 to activate the connector as described above for FIG. 8 .
[0078] FIG. 20 illustrates a flexible drive 500 that is similar in construction and function to the flexible drive 450 , and that is connected between the connector body 12 and the actuation unit 160 described above in FIG. 9 .
[0079] FIG. 21 illustrates a flexible drive 510 that is similar in construction and function to the flexible drive 450 , and that is connected between the connector body 12 and the actuation unit 180 described above in FIG. 10 .
[0080] FIG. 22 illustrates a flexible drive 520 that is similar in construction and function to the flexible drive 450 connected between the connector body 12 and the actuation unit 200 described in FIGS. 11A-E .
[0081] FIG. 23 illustrates a flexible drive 530 that utilizes hydraulic activation but where the processing fluid exits from the connection unit through the forward end of the flexible drive 530 . The flexible drive 530 includes a hollow, flexible hydraulic line 532 that contains hydraulic fluid. One end of the line 532 is connected by a cap 534 to the end 24 of the sleeve 20 . The front end of the piston 30 is modified with an exterior channel to receive an o-ring 536 for sealing with the interior of the sleeve 20 .
[0082] The opposite end of the line 532 is of enlarged size and includes a threaded fitting 538 secured thereto for passage of process fluid. The line 532 is connected to the connection unit 180 described in FIG. 10 . A piston 540 is disposed within the enlarged end of the line 532 , with the piston secured to the tube 184 . O-rings 542 , 544 are provided forwardly of the fitting 538 to seal between the piston 540 and the tube 184 , and between the piston 540 and the interior of the line 532 . In addition, an o-ring 546 is provided to seal between the rear of the piston 540 and the interior of the line 532 . In addition, radial flow passages 548 are formed in the piston 540 and fluidly connect the hollow interior of the tube 184 with the fitting 538 to permit processing fluid to flow.
[0083] In use, actuation of the piston 30 in a forward direction decreases the volume of the hydraulic chamber, causing the hydraulic fluid to push on the rear of the piston 540 thereby forcing the piston, and the tube 184 , forward to activate the connection unit 180 as described above in FIG. 10 .
[0084] FIG. 24 illustrates a flexible drive 560 that is similar in construction and function to the flexible drive 530 , but which is connected to the connection unit 160 described above in FIG. 9 .
[0085] The flexible drives of FIGS. 19-24 can be used with any connection unit, including any connection unit described herein, which is suitable for being activated by the hydraulic activation that is described.
[0086] FIG. 25 illustrates an embodiment of a connector 600 that includes the connector body 12 , and a connection unit, for example connection unit 16 . In FIG. 25 , the same reference numerals indicate elements that are similar to those described above in FIGS. 1-6 . The connector 600 is similar to the connector 10 described above, except that the electric motor 34 and the reduction mechanism 38 are not connected to the connector 600 . Instead, the connector 600 is provided with an interface to which a drive mechanism connects to actuate the connector. With this embodiment, the drive mechanism can stay with a station while the connector 600 moves down an assembly line connected to the interface of the second fluid system. At the end of the assembly line, another drive mechanism can be provided to remove the connector 600 from the second fluid system.
[0087] The interface of the connector 600 includes a screw drive shaft 602 connected to the drive nut 48 . The shaft 602 extends rearwardly to a free end 604 that is suitably shaped for engagement by a drive mechanism. A clutch mechanism 606 is fixed to the rear of the nut 32 via the flange 40 . The clutch mechanism 606 resists unwanted loosening of the connector 10 while traveling down the assembly line.
[0088] In use of the connector 600 , a drive mechanism (not shown) at a station is connected to the connector 600 . The drive mechanism connects to the nut 32 and to the free end 604 of the shaft 602 . Engagement with the nut 32 prevents rotation of the nut and connector during rotation of the shaft 602 . The drive mechanism then rotates the shaft 602 to actuate the drive nut 48 and the connection unit 16 as described above for FIGS. 1-6 .
[0089] The invention may be embodied in other forms without departing from the spirit or novel characteristics thereof. The embodiments disclosed in this application are to be considered in all respects as illustrative and not limitative. The scope of the invention is indicated by the appended claims rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein. | 4y
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CROSS REFERENCE TO RELATED APPLICATIONS
This is a United States national stage of International application No. PCT/AU97/00458, filed Jul. 18, 1997, the benefit of the filing date of which is herby claimed under 35 U.S.C. §120, which in turn claims the benefit of Australian application No. PO 1102, filed Jul. 18, 1996, the benefit of the filing date of which is hereby claimed under 35 U.S.C. §119.
FIELD OF THE INVENTION
The present invention relates to a process for producing metal articles using thixoforming.
BACKGROUND OF THE INVENTION
Semisolid metal processing is generally used to refer to any processing of a metal alloy at temperatures between the solidus and liquidus temperatures of that alloy. Semisolid metal processing involves producing a thixotropic material that comprises a mixture or slurry of solid metal particles and molten (or liquid) metal and subsequently forming or shaping the thixotropic material. The term “semi-solid metal processing” conventionally encompasses both the methods of producing the thixotropic material and the subsequent forming or shaping of the thixotropic material. There are two major categories of semisolid metal forming processes that can be identified:
a) rheoprocessing, in which an alloy is fully melted by heating to a temperature above the liquidus temperature and the melt is then cooled to a temperature between the solidus and liquidus temperature to thereby produce the thixotropic material, and subsequently forming or shaping the thixotropic material. An example of rheoprocessing is rheocasting; and
b) thixoforming, in which a semisolid metal processing feedstock is produced by cooling a semisolid slurry to fully solidify the metal. The feedstock is then reheated to a temperature between the solidus and liquidus temperatures to produce a thixotropic material just prior to being shaped.
Thixoforming processes are further subdivided, if rather arbitrarily, into categories according to the conventional metal shaping technologies with which they are comparable in terms of general processing and especially in terms of the actual machinery used for metal shaping. For example, thixocasting is based on liquid metal die casting technology, where as thixoforging is more akin to solid metal forging, for example, in the use of vertical forging presses in shaping of the articles. While there seems to be some difficulty in literature and the industry in drawing a clear line between thixocasting and thixoforging processes, there is a clear distinction between thixoforming and conventional metal processing (e.g. casting and forging). Thixoforming is a new development in metal shaping processes in that the metal is being shaped in its partially solid, partially liquid (i.e. semisolid) state, rather than in the fully liquid (casting) or fully solid (forging) state.
It is generally understood that a basic requirement for an alloy to be satisfactorily used in a thixoforming process is that the alloy has a globular, non-dendritic microstructure which when reheated to the partially solid/partially liquid state forms a slurry of solid globular particles of primary phase suspended in a lower melting point constituent which is the liquid component of the slurry. It is such a slurry which is subsequently thixoformed. Thixoforming has many advantages over conventional forging operations. Most of these are directly related to the excellent flow characteristics of semisolid thixotropic materials. The forming stresses are up to four orders of magnitude lower in the semisolid state for thixotropic materials. It follows that more intricately shaped components can be formed in a single step to net or near net shape. In relation to conventional forging in particular, this also means that parts can be manufactured faster with a smaller number of processing steps and using smaller presses. Thixoforming also permits the shaping of otherwise unforgeable alloys.
Considerable effort has been devoted to obtaining alloys that have a microstructure suitable for thixoforming. Production of thixoforming feedstock alloys having the desired microstructure have conventionally involved treatment of a thixotropic material by stirring either mechanically or electromagnetically. It is believed that stirring the thixotropic material alters the normally dendritic shape of the solid particles in the thixotropic material to form globular particles which remain after the alloy is allowed to solidify. Other methods for producing the desired microstructure include deforming and reheating to the recrystallisation or semisolid temperature range, direct partial remelting of castings and extrusions, grain refining plus partial remelting, and static stirring. These methods suffer from the disadvantage that they require elaborate processing or specially designed apparatus.
Brinegar et al in U.S. Pat. No. 4,832,112 describe a method of forming a fine grained equiaxed castings from molten metals to produce ingots, forging preforms and investment castings. The method described in this patent relates mainly to supbralloys used in the aerospace industry and is directed towards producing a chemically homogeneous, fine grained and sound product. The method involves melting a metal with the temperature of the molten metal being reduced to remove almost all of the superheat in the molten metal, The molten metal is placed in a mould and solidified by extracting heat from the mixture at a rate to solidify the molten metal to form the solid article and to obtain a substantially equiaxed cellular microstructure uniformly throughout the article. When used to make ingots, turbulence is induced in the molten metal prior to its introduction to the mould or while it is in the mould. U.S. Pat. No. 4,832,112 suggests that the temperature of the molten metal have, at the time of casting, a temperature that is within 20° F. (11.1° C.) above the measured melting point of the metal.
As mentioned above, the method of U.S. Pat. No. 4,832,112 is used to make investment castings, ingots or forging preforms. The patent makes no mention of thixoforming and indeed the emphasis in his patent on the fine grain size for improved forgeability and improved properties in an investment casting would teach the skilled person away from post treatment of the product of U.S. Pat. No. 4,832,112 by thixoforging as the partial remelting required in thixoforming potentially would cause coarsening of the grain size.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved process for producing a solid article by semi-solid processing, such as thixoforming.
In a first aspect, the present invention provides a process for producing a solid article including the steps of melting a metal alloy to produce a molten metal, reducing the temperature of the molten metal to a temperature of from substantially the liquidus temperature to about 5° C. above the liquidus temperature, casting said molten metal at said temperature, solidifying the cast metal to produce a solidified metal, partially remelting the solidified metal by heating the solidified metal to a temperature between the solidus temperature and the liquidus temperature to produce a thixotropic material and forming the thixotropic material to a desired shape.
The present inventors have discovered that by very carefully controlling the temperature of the molten metal at casting to a temperature of from substantially the liquidus temperature to about 5° C. above the liquidus temperature, the solidified metal thus obtained is especially suitable for use in thixoforming and indeed significant and surprising advantages accrue in the subsequent thixoforming process. The present inventors have also discovered that very beneficial results are obtained if the temperature of the molten metal at casting is within the range of from the liquidus temperature to about 5° C. above the liquidus temperature and this temperature range represents a preferred embodiment of the present invention. Even more preferably, the temperature of the molten melt at casting is within the range of from the liquidus temperature to about 2° C. above the liquidus temperature, Most preferably, the molten metal is cast at the liquidus temperature.
Those skilled in the art will appreciate that control of temperature in molten metal casting requires that the temperature of the molten metal be measured and that the temperature of the molten metal be controlled. Both temperature measurement and temperature control will have a degree of uncertainty associated therewith.
Currently available techniques enable highly accurate temperature measurement to be made.
Turning to consider temperature control, it is desired to control the temperature of a pool of molten metal, which is typically held in a furnace, ladle or holding vessel. In such situations, it will be appreciated that accurate temperature control depends on several factors including the volume of metal, the furnace type and configuration, casting method and the temperature control system used.
Good temperature control can be achieved with the right temperature control and monitoring system, but would become progressively more difficult as the volume of melt to be held at precisely or within a couple of degrees of the target temperature, increases. Assuming that a reliable temperature reading is obtained, the spatial temperature distribution (temperature uniformity) within a volume of melt is best measured by a number of probes distributed throughout the volume. The number and placement of probes would depend on the desired accuracy. The probe output should be linked to furnace control which can then adjust input power to keep the melt within a specified temperature range. The ease and speed of achieving this of course depends on the furnace itself and the sensitivity and programming of its control systems. Again, the degree of accuracy achievable should be specified by equipment manufacturers, and give acceptable confidence interval.
High volume continuous type casting production tends to have quite sophisticated temperature control systems as the casting temperature is an important and sensitive variable irrespective of the actual casting temperature. It is not unusual to achieve temperature uniformity to well within and better than 5° C. if so required, in large volumes of metal.
The casting procedure will also play an important role in temperature control. The molten metal cannot be simply held in a ladle from which it is scooped out and put into moulds. The holding vessel will most likely need to be a well controlled furnace with preferably bottom pouring type arrangement, or a tilting furnace. This would ensure that the remaining metal pool is kept at the right temperature while casting proceeds.
Thus, current temperature control techniques allow the temperature of the molten metal to be controlled to the accuracy required by the present invention. In particular current techniques will allow the temperature to be set at the liquidus temperature and controlled to within 5° C. above that temperature. Indeed, the present inventors have achieved temperature control to within 2° C. of the desired temperature in the experimental work conducted in relation to the present invention.
It is also to be understood that the actual temperature control system does not form part of the present invention and that the present invention encompasses within its scope all temperature control systems that are capable of achieving the desired accuracy and control.
The lower limit of temperature range for casting is the liquidus temperature or no more than 2° C. below the liquidus temperature. It will be appreciated that it is preferred that the temperature of the molten metal is kept at or above the liquidus temperature (within the upper limits prescribed above) prior to casting to minimize or avoid solidification in the vessel containing the molten metal.
By casting the molten metal at a temperature from substantially the liquidus temperature to no more than 10° C., more preferably no more than 5° C. above the liquidus temperature to form the solidified metal, it has been surprisingly discovered that the solidified metal can be partially remelted and thixoformed and that significant benefits accrue in the thixoforming process. For example, the processing windows for the thixoforming process are larger. Tests conducted by the present inventor have shown that thixoforming can be easily conducted using high solids fraction, low die temperature and low forming speed whereas other materials would require lower solids fraction and higher forming speeds to obtain similar results. Lower forming speeds and die temperatures would ease wear and maintenance on the thixoforming equipment whilst allowing the specification of lower cost materials of construction in the thixoforming apparatus. High solids fraction may be desirable because the flow pattern formed into the final article under conditions of thixoforging at high solids content has the potential to enhance the strength of the final article.
In a preferred embodiment of the present invention, the molten metal is cast at precisely its liquidus temperature.
The solidified metal produced from casting of the molten metal and subsequent solidification is preferably in the form of a billet or ingot. The solidified metal has been found to have an as-cast microstructure that contains independent globules separated by a phase of lower melting point material (normally eutectic phase). Upon heating the solidified metal to a temperature between the solidus and liquidus temperatures, a semi-solid material or slurry comprising solid particles and molten metal alloy is obtained. Due to the morphology of the solidified metal, in having a globular primary grain structure, it is not necessary to hold the semi-solid material at the thixoforming temperature for any length of time before thixoforming the material. This was a requirement of some prior art feedstock materials in order to allow the required morphology to form in the semi-solid material.
A large number of metal alloys may be used in the process of the present invention. Examples include aluminum alloys, magnesium alloys, copper alloys, ferrous alloys, and superalloys. This list is not exhaustive. Preferred alloys for use in the present invention include those shown in Table 1:
TABLE 1
Alloy
Group/Grade
Nominal Composition/Composition Range (wt.%)
Aluminium
2014
4.4 Cu, 0.8 Si, 0.8 Mn, 0.5 Mg
2618
2.3 Cu, l.6 Mg, 1.1 Fe, 1.0 Ni, 0.18 Si, 0.07 Ti
6061
1.0 Mg, 0.6 Si, 0.30 Cu, 0.20 Cr
6082
0.6 Mg, 1.0 Si, Cr 0.25
7075
5.6 Zn, 2.5 Mg, 1.6 Cu, 0.23 Cr
Magnesium
AZ80
7.8-9.2 Al, 0.20-0.8 Zn, 0.12 Mn (min), 0.10 Si (max),
0.05 Cu (max), 0.005 Ni (max), 0.005 Fe (max)
AZ91D
8.5-9.5 Al, 0.45-0.9 Zn, 0.15-0.40 Mg, 0.015 Cu
(max), 0.020 Si (max),0.005 Fe (max), 0.005 Ni (max)
AZ6lA
5.8-7.2 Al, 0.15 Mn (min), 0.40-1.5 Zn, 0.10 Si
(max), 0.05 Cu (max),0.005 Ni (max), 0.005 Fe (max)
AM60A
5.5-6.5 Al, 0.13 Mn (min), 0.50 Si (max),0.35 Cu (max),
0.22 Zn (max), 0.03 Ni (max)
Copper
C36000
61.5 Cu, 35.5 Zn, 3 Pb
C84400
81 Cu, 9 Zn, 3 Sn, 7 Pb
C87800
82 Cu, 14 Zn, 4 Si
C83600
85 Cu, 5 Zn, 5 Sn, 5 Pb
Steels
H13 tool
0.32-0.45 C, 0.20-0.50 Mn, 0.80-1.2 Si, 4.75-5.50 Cr,
1.10-1.75 Mo, 0.80-1.75 V
304 stainless
0.08 C, 2 Mn, 1.0 Si, 18.0-20.0 Cr, 8.0-10.5 Ni,
0.045 P, 0.03 S
316 stainless
0.08 C, 2 Mn, 1.0 Si, 16.0-18.0 Cr, 10.0-14.0 Ni,
0.045 P, 0.03 S, 2.0-3.0 Mo
Titanium
Ti-2.5 Cu
2.0-3.0 Cu, Ti (remainder)
Ni superalloys
Monel 400
63 Ni, 28-34 Cu, 2.5 Fe
Monel 401
40-45 Ni+Co, 2.5 Fe, Cu (remainder)
Monel 450
29-33 Ni, 1.0 Mn, 1.0 Zn, Cu (remainder)
Inconel 718
50-55 Ni, 17-21 Cr, Fe (remainder)
The step of casting the molten metal at a temperature of from substantially the liquidus temperature to about 5° C. above the liquidus temperature may comprise casting the molten metal into a mould, preferably a steel mould, with the mould being at ambient temperature or at an elevated temperature. In another embodiment, the casting step may include continuously or semi-continuously casting the molten metal, for example, to form billet or ingot. In embodiments where continuous or semi-continuous casting is used, the casting apparatus may be supplied with molten metal from a source of molten metal held at substantially the liquidus temperature. Alternatively, a holding furnace or other source of molten metal may hold the molten metal at a temperature above the liquidus temperature and the molten metal may be cooled to substantially the liquidus temperature when or after the molten metal is transferred to the casting apparatus.
In the thixoforming step of the present invention. The thixotropic material is preferably self supporting in that it will hold its shape in the absence of applied external forces. The semi-solid or thixotropic material formed by partially remelting the solidified metal preferably contains a solids fraction of from 0.6 to 0.8, by volume. The forming speed used during thixoforming may be relatively low and the die temperature during thixoforming may also be relatively low. For example, the forming speed may fall within the range of about 0.1 m/s to about 0.2 m/s. The die temperature may fall within the range of about 150° C. to about 300° C.
The process of the present invention allows a combination of thixofonning operating parameters to be used that had conventionally been believed to be unsuitable for producing articles other than simple test components. The combination of thixoforming operating parameters that can be used in the present invention include high solid content in the semi-solid material, low forming speed and low die temperature.
BRIEF DESCRIPTION OF THE DRAWINGS
Examples of preferred embodiments of the present invention will now be described with reference to the accompanying Figures in which:
FIG. 1 shows a photomicrograph of the microstructure obtained by casting aluminum alloy 2618 from its liquidus temperature;
FIG. 2 shows a photomicrograph of the microstructure obtained by casting aluminum alloy 2618 from a temperature of 50-60° C. above its liquidus temperature;
FIG. 3 shows a photomicrograph of the metal casting shown in FIG. 1 after the casting has been heated to a temperature between the solidus and liquidus temperature;
FIG. 4 shows a photomicrograph of an article formed by thixoforming the material shown in FIG. 3;
FIG. 5 shows a schematic diagram of the thixoforming process used in the present invention;
FIG. 6 shows a cross-sectional, side elevation of a clutch hub formed in accordance with the present invention;
FIG. 7 shows a sectional view of the clutch hub shown in FIG. 6 showing regions of heavy flow and recrystallisation in a clutch hub formed from thixotropic material having a solid content of 75-80% by volume;
FIG. 8 is a similar figure to FIG. 7 but shows regions of heavy flow and recrystallisation in a clutch hub formed from thixotropic material having a solid content of 60-70% by volume;
FIG. 9 is a photomicrograph of a sample taken from Region A 1 of FIG. 7; and
FIG. 10 is a photomicrograph of a sample taken from Region A 2 of FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
In order to demonstrate the advantages of the present invention, a series of experimental tests were conducted in which an aluminum alloy was heated up to a temperature above the liquidus temperature to fully melt the alloy. The molten alloy was cooled to precisely its liquidus temperature (still in the fully liquid state) and cast into a steel mould at room temperature. FIG. 1 shows a photomicrograph of the structure obtained for an aluminum alloy 2618. About 450 g of this alloy was heated to above the liquidus temperature of 638° C. and then cooled to precisely 638° C. The molten alloy was then cast into a cylindrical steel mould having an outer diameter of 120 mm and an outer length of 140 mm. The mould cavity of this mould had a diameter of 50 mm and a length of 80 mm. The mould was at ambient temperature when casting commenced.
As mentioned above, FIG. 1 shows a photomicrograph of the as cast structure obtained from this experiment. Misorientation measurements between the particles and three-dimensional imaging of the particles in FIG. 1 indicate that they are independent globules separated by eutectic phase.
FIG. 2 shows a photomicrograph of the as-cast structure obtained using similar apparatus but with casting conducted in the conventional manner in which the melt is cast at a temperature of about 50-60° C. above the liquidus temperature. As can be seen from FIG. 2, a dendritic structure is obtained. This structure is not especially suitable for thixoforming.
The microstructure obtained in 2618 alloy has been reproduced in other wrought and casting alloys, such as 2011 (wrought alloy), 7075 (wrought alloy), and A356 (casting alloy) by casting those alloys from their liquidus temperature.
A total of over 54 experiments were carried out to produce materials of various compositions (i.e. commercial compositions of aluminum alloys 2618,2011,7075 and A356) and microstructures (i.e. as-liquidus-cast, as conventional-cast, as-reheated and as-formed). The microstructure of the materials was examined by optical microscopy and image analysis to ascertain the non-dendritic structure. The thixotropic structure was further confirmed by three dimensional modelling and by measuring the orientations of adjacent grains by using scanning electron microscopy and electron back scattered pattern.
The liquidus-cast 2618 slugs were reheated to semisolid temperature range to have about 60% solid and 40% liquid. The slugs were then either cut through using a knife edge or compressed manually by a flat ceramic tool to show the ability of the material to deform easily. (It was impossible to do so with the conventionally cast material). This shows the suitability of the material for use in thixoforming.
In further experiments, the as-liquidus-cast alloy was subsequently reheated to the desired processing temperature in the solid-liquid region followed by thixoforrning into near-net-shape. The microstructure after reheating of a liquidus cast 2618 alloy is shown in FIG. 3; the fine, non-dendritic structure is retained. The microstructure after thixoforming is shown in FIG. 4; the flow is homogeneous.
Thixoforming Examples
In order to further demonstrate the present invention a number of further experiments were conducted in which solidified metal, obtained from casting molten metal at substantially the liquidus temperature to produce a billet of appropriate dimensions, was brought to the semi-solid regime using an induction heating furnace. The billet was held in the induction heating furnace for a time of 2-3 minutes. The resulting semi-solid billet was then shaped under desired forming conditions using a commercial 500 tonne hydraulic press.
In the thixoforming process used in the following Examples, the billet of thixotropic material is introduced into open dies which subsequently close to form the article, and then open again for the ejection of the finished component. This is opposed to and believed to be unique over known thixoforming processes that use forming processes that are akin to die casting in which a thixotropic material is injected into a set of closed dies through a shot sleeve. However, the open die thixoforming process must not be confused with conventional open die solid forging. In fact, the open die thixoforming process of the present practice is more akin to conventional closed die solid forging, in the same way in which thixocasting can be likened to liquid die casting, for example.
A typical thixoforming cycle as practiced in the present “open die” approach used in the following Examples and shown schematically in FIG. 5 consists of the following steps: (a) billet reheating, in which billet 10 is supplied to induction heating means 12 and heated to a temperature between the solidus and liquidus temperature to produce a thixotropic material. The thixotropic material is preferably self-supporting (b) billet transfer to open dies, 14 , 16 (c) forging stroke initiation and forming, and (d) removal of thixoformed component (not shown). Just as a billet, 10 being reheated to a desired semisolid condition, is ready for transfer to the press, 13 the dies 14 , 16 open and the billet 10 is removed from an induction heating coil case 12 and seated in the lower die 16 . Once the semisolid (thixotropic) billet 10 is positioned, the press operator initiates the forming cycle (defined by the pre-set forming speed, and final forming load) and the billet 10 is thixoformed upon the approach of the top die 14 and its closure onto the lower die 16 . During the forming cycle the thixotropic billet 10 is forced to follow the contours of the dies. The dies stay closed for a predetermined time (dwell time). After the elapse of the dwell time the dies open, the thixoforged article 18 is removed by the press operator, and the dies are closed again so that they are maintained at the correct temperature by a gas ring heater. A typical forming cycle, defined by the time from semisolid billet removal from the heating coil, and including its placement in the press and forming by die closure, is less than 20 seconds.
Using the above process, the commercially available aluminum alloy 2618 was thixoformed under various forming conditions (to be discussed hereunder). The billet of solidified metal was obtained by casting molten metal from the liquidus temperature. The demonstration article thixoformed in the Examples is an automotive clutch hub component 20 as shown in FIG. 6 . This component has previously been manufactured from steel by conventional forging methods. In conventional forging methods for producing this component, the component was made with the use of two die sets, blocker and finisher die and was subject to finishing/machining operations. When the article was produced by thixoforming in accordance with the present invention, only the finisher die was required to arrive at a near net shape compound in a single step.
The starting thixotropic material provided to die 14 is a self-supporting cylindrical billet having a ratio of height to diameter (H/D) of about 1.4. The thixoforming step used to produce the clutch hub shown in FIG. 6 reduces the height of the billet to about 40% of the original height in the central region of the hub and to about 11% of the original height in the peripheral flange portion of the hub. The final diameter of the hub is approximately 2.4 times the diameter of the cylindrical billet of thixotropic material.
It can be seen from FIG. 6 that while the cross-section of the clutch hub 20 is a relatively simple symmetrical shape (essentially a flat plate 22 extending radially from a centrally located hub region 24 of a wider cross-section), the detail of the flange periphery 26 shows that good flow characteristics are required to faithfully reproduce this particular feature of the article.
The clutch hub 20 was successfully thixoforged from alloy 2618 under a wide range of thixoforming conditions. Process parameters investigated were (a) semisolid condition, ie. fraction of solid phase in the starting billet; (b) die temperature; and (c) forming speed. All of these are related to the ease (or lack thereof) with which an article can be thixoformed. Generally, the lower the fraction of the solid phase and the higher the fraction of the liquid constituent, the less viscous is the semisolid slurry charge and the easier it is to deform. The resistance of a semisolid slurry system to applied force increases steeply with increasing fraction of solid in the material, for the range of fractions solid that can be practically applied in semisolid forging (ie. 0.8> fraction solid >0.5). Die temperature is most often related to surface finish of thixoforgings, where higher die temperatures tend to produce better surface finish and also prevent premature freezing of the semisolid slurry charge on contact with the dies. The forming speed is related to the rate of shearing (deformation) of the semisolid charge, and generally the higher the shearing rate, the lower the resistance of the semisolid slurry system to the applied load. Another obviously important variable is the applied load necessary for the deforming (shaping) of the semisolid charge, and this may be several orders of magnitude less in thixoforming than is required in conventional forging.
In a total of 25 thixoforming trials, clutch hubs were successfully thixoformed at solid fractions in the semi-solid material of 0.8> fraction solid >0.6, at die temperatures from 150-300° C., and forming speeds of 0.1-0.2 m/s. The forming load was 350 tons (well below the press capacity), and it was obvious that a much smaller forming load would suffice. The full forming load was only applied as the final clamping load, which is produced only after the top and bottom dies come in contact and fully close.
The fraction solid of the semisolid charge was varied from low (60% solid) to medium (70% solid) to high (80% solid), and for each fraction solid the forming speed was varied from slow (˜0.1 m/s) to medium (0.2 m/s). Low (150° C.) or high (300° C.) die temperature did not at all affect the surface finish quality of the thixoforged clutch hubs. In all of the thixoforging trials fully dense, near net clutch hubs were produced to the shape dictated by the forging dies.
In summary, the solidified metal produced by casting a billet from molten metal at the liquidus temperature showed extremely favourable thixoforming characteristics. A part (automotive clutch hub) which required a substantial change in dimensions from the starting billet to the final article, was easily thixoformed in a single step, to near net shape as dictated by the forging dies, under a wide range of thixoforming conditions. The conditions included quite a high solid fraction of the semisolid charge (80% solid), quite cool forging dies (150° C.), and only moderate forming speeds. Preliminary results from the die filling characteristics during thixoforging show that the load-stroke profile for the deformation of a semisolid charge of alloy 2618 is very close to a profile obtained when the press is run with empty dies (ie. demonstrating minimal flow resistance of the semisolid charge).
Some typical windows of processing conditions for prior art thixoforging (as distinguished from thixocasting) can be compiled from data available in literature. It is claimed that for very simple test components (eg. a flat disc) a component can be thixoforged at fractions of solid of 40-80%, at forming velocities of 0.1-0.5 m/s, and with dies at 150-300° C. For thixocasting, lower fractions of solid (40-60%) and much higher forming speeds (>1 m/s) are necessary. The size of the processing window, or the flexibility of the thixoforming process is in either case heavily dependent on the quality of the thixoforming feedstock, and also on the complexity of the article to be produced. This again highlights the quality of the starting material produced by casting from substantially the liquidus temperature because fully dense and fully formed parts are easily produced at the outer limits of processing conditions as indicated in literature, under which a sound article can normally be produced (ie. high fractions of solid in the starting slurry, low die temperatures, and slow forming speeds). In fact, it would seem from published results that such outer limits as demonstrated here in the thixoforming of the clutch hub, are not usually viable for the production of realistic articles, with the exception of overly simplistic test components as mentioned previously.
The microstructure of the thixoformed components as (thixo) formed by the present ‘open die’ thixoforging process is somewhat unusual. The microstructural characteristics across the section of the clutch hub components are summarised in FIGS. 7, 8 , 9 and 10 . In FIG. 7, the regions of heavy flow and recrystallisation are denoted by flow lines 30 . It can be seen from FIGS. 7 and 10 that there are regions where the primary particles (the solid constituent during the forming of semisolid slurry charge) are deformed, indicating the direction of flow of the semisolid charge during forming. It is seen that the grains in the ‘flow’ region are substantially changed from the globular grains in the original billet. The flow regions are found in the central part of the hub and along the periphery of the flange. In other regions, the primary globular grains remain largely unchanged from how they appear in the original reheated thixotropic billet just prior to forming (see FIG. 9 ). The extent of the flow regions is found to be dependent on the initial fraction of solid in the starting billet. At higher fraction of solid phase, these regions are found to increase (as shown in FIG. 7 ), and at lower fraction solid they are reduced (as shown in FIG. 8 ). The location of the flow regions is the same irrespective of the fraction of solid phase in the starting billet, only their extent changes according to solid fraction, as mentioned previously.
In the view of results presented in thixoforging literature 1,2,3 this is an unexpected result, as there is no mention of flow patterns in thixoforged components. Microstructures presented in literature are akin to those in the unchanged regions without flow in the above example. It can also be postulated on the basis of the above results, that the flow patterns are likely to disappear if the fraction solid in the starting billet is substantially low. It would seem from the results obtained so far that negligible flow pattern or no flow pattern at all could be obtained at fractions solid of less than 60%.
The mechanical properties of clutch hub parts thixoformed from alloy 2618 are quite encouraging and are summarised in Table 2. Tests were carried out strictly according to standard ASTM E8- 96. Tensile properties of thixoforged parts are markedly improved by heat treatment.
TABLE 2
Preliminary results of tensile tests on alloy 2618 thixoforged clutch hubs.
Heat
Ultimate Tensile
Yield Strength
Tensile
Treatment
Strength (MPa)
(MPa)
Elongation (%)
As thixoforged
300
150
15
T5
312
235
8
T6
397
341
5
The results compare very favourably to those presented for thixoforgings in literature, as shown in Table 3 below, although a direct comparison is not possible since there are no other results concerning alloy 2618. In terms of ultimate tensile and yield strengths the present results are at least as good as but mostly better than those presented for comparable alloys (from the 2000 series) and for comparable heat treatment regimes (T5 or T6). The tensile elongation is also similar to results presented for thixoforgings in literature.
TABLE 3
Properties of Prior-Art, Thixoforged Articles (from Literature) 4
Ultimate
Yield
Tensile
Heat
Tensile
Strength
Elongation
Alloy
Treatment
Strength (MPa)
(MPa)
(%)
2017
T4
386
276
8.8
2219
T8
352
310
5
6061
T6
330
290
8.2
It is also very encouraging that the mechanical properties of the present thixoforgings are close to or better than those expected from conventionally (solid) forged components. In the T6 condition conventional alloy 2618 forgings are expected to have ultimate tensile strength of 400 MPa, yield strength of 310 MPa, and tensile elongation of 4%. It should be noted at this stage that the present thixoforging process is not yet fully optimised, and further improvements in properties of thixoforgings are expected.
It is very interesting to note that the excellent tensile properties of the thixoformed clutch hubs can be related to the unique microstructure of the thixoformed parts. Samples were taken from regions of the components that contained the “flow patterns” and from those without. Regions with flow patterns showed the excellent tensile properties mentioned above, where as regions where flow of material was not observed showed somewhat lower (but still impressive) tensile strengths and elongations. It can therefore be concluded that the flow structure is a desirable outcome of the present thixoforming process, which has a positive bearing on the tensile properties of the thixoformed parts.
It will be appreciated that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention encompasses all such variations and modifications that fall within its spirit and scope.
REFERENCES
1. Hirt, G., Winkelmann, A., Witulski, T. and Ziligen, M., “Third International Conference on Processing of Semi-Solid Alloys and Composites” (ed. Kiuchi, M.) 107-116 (Institute of Industrial Sciences, University of Tokyo, Tokyo, Japan, 1994).
2. Kenney, M. P., et. al., in “Metals Handbook, Volume 15: Casting” (eds. Cubberly, W. h.) 327-338 (ASM International, Ohio, 1988).
3. In “Fourth International Conference on Semi-Solid Processing of Alloys and Composites”, Chapter 5a: Industrial Applications: Component Manufacture (eds. Kirkwood, D. H., and Kapranos, P.) 204-256 (The University of Sheffield, England, 1996).
4. In “Metals Handbook, Volume 2: Properties and Selection: Nonferrous Alloys and Pure Metals” (eds. Cubberly, W. H. et.al.) AMS International, Metals Park, Ohio, 1990. | 4y
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BACKGROUND OF THE INVENTION
It is known to design the filler connection for a fuel tank in one piece with the filling tube; length and guidance of the filling pipe which normally consists of sheet metal being governed in this arrangement by the position of the fuel tank. Even though the construction of the one-piece filling tube does not cause so much difficulties problems, however, will arise in connection with the fitting thereof in the body. As there is no elastic intermediate member available, it is difficult to match the tolerances of tank and body. For the above reason the filler connections are normally manufactured as separate parts which are then soldered, welded or otherwise connected, for instance, through an elastic socket or with the aid of pipe clips or the like. But even these filler connections suffer from quite a few drawbacks. Because of the metallic material numerous reworking operations are necessary which brings about corresponding expenses in terms of manufacturing costs. Numerous additional elements are required for fastening to and sealing with respect to the body. Usually, the known filler connections are fastened at the body by means of several screws tightly pulling the filler connection against the sheet metal of the body.
To prevent corrosion the filler connections are covered with a corrosion protection means the layer of which may be easily damaged in the rough operation during the filling-in of the fuel so that corrosion will yet occur. What is furthermore disadvantageous is that it is difficult with a pipe construction of sheet metal to arrive at small structural dimensions because the overflow connection, in particular, must be designed in the form of a pipe bend and thus requires considerable space.
The "tank cover" which closes the filler connection outside is either designed in the manner of a bayonet closure (which is the most widely accepted embodiment) or is provided with an inner or outer thread and screwed onto the connection. With both types of closure, however, difficulties will result as regards the loosening moment. With a bayonet closure the possible forces of stripping off the cover are relatively small and, in addition, are strongly dependent upon the properties and the design of the material that has been selected. With a threaded closure the loosening moment of the cover is strongly dependent upon the tightening moment, especially because of an axial sealing being used. For this reason, many threaded covers are provided with a special ratchet arrangement. Furthermore, it is difficult with a filler connection of sheet material to provide a greater threaded engagement for the closure lid so that here as well the pull-off forces are relatively low.
Additional provisions are required at the overall tank system to guarantee operation and safety in a satisfactory manner. This includes valve means for ventilation during fuel consumption and venting in case overpressure should occur, for instance, due to heating in the sun, etc. Furthermore, care must be taken for the air present in the tank to escape quickly enough during the filling-in of the liquid fuel. In many cases the valve means are provided in the closure lid which, consequently, is of an extremely expensive design. Another disadvantage of the closure lid performing valve functions resides in that fuel escaping through the venting valve will form traces over the outside of the body thus causing an increased danger of fire.
The invention has for its object to provide a filler connection for vehicles equipped with internal combustion engines which avoids the above mentioned disadvantages, is of a simple design and may be easily fitted, while being provided with a simply equipped closure lid through which no fuel may escape to the outside of the vehicle.
With a filling connection of the type mentioned at the beginning this problem is solved in that it is formed integrally of synthetic material and the valve means are arranged on the portion disposed on the inside of the body.
The filler connection according to the invention is a member of synthetic material formed in one piece which may be designed in such a manner that it is in a position to perform all the necessary functions satisfactorily. This includes the arrangement of the valve means at the filler connection so that the closure lid may correspondingly be manufactured as a member of a simple construction which is formed in one piece - in an embodiment not adapted to be closed. For this reason, the fuel is unable to escape outside and cannot mar the good appearance of the outer skin of the body and cause an increased danger of fire.
Through the formation of the filler connection in accordance with the invention as a member of synthetic material it is possible to obtain a favourable configuration also with a view to the fastening in a sheet metal member of the outer skin of the vehicle. In this connection provision is made in one embodiment of the invention for the filler connection to be in snapping engagement in the body opening and fastened therein. Therefore, there are no additional parts necessary to fasten the filler connection, and also the mounting itself is extremely simple because the filler connection has only to be introduced and snapped into the sheet metal opening. In this connection provision is made in another embodiment of the invention for the use of elastic synthetic material and for a radial abutment, preferably a flange formed integrally therewith, said flange lying close to one side of the body skin while at least one arresting nose is formed integrally on the other side of the body skin. If, in accordance with another embodiment of the invention, an annular seal is arranged between the abutment and the body skin, there will result not only an extremely simple and secure fastening but also a sufficient sealing of the connection in the opening, so that for instance when filling-in fuel no liquid whatsoever can flow past the filler connection and into the interior of the body.
The filler connection in accordance with the invention furthermore possesses the advantage that it may be equipped with a sufficiently strong and long thread which will permit fastening of the closure lid by threaded engagement. In this connection, provision is made in another embodiment of the invention for the outer portion to have a external thread formation, preferably a sawtooth thread formation onto which the lid can be screwed by means of a fitting inner thread, said lid being likewise preferably formed in one piece from synthetic material. With the aid of such a closure it is rendered possible for the loosening moment of the closure lid to be made approximately as great as the tightening moment, especially, if, in accordance with another embodiment of the invention, there is an axially and/or radially effective annular seal arranged at the thread of the lid, with the seal disposed at the inner surface of the thread of the lid and cooperating with the end face of the outer portion of the filler connection or arranged at the lower end of the thread of the filler connection and cooperating with the inside of the outer portion of the lid. The sealing element is preferably endowed with a relatively high elasticity of its own or dimensional elasticity, respectively, and is resistant to fuel.
To avoid an inadmissibly high torque and extremely high loads on the sealing caused thereby, provision is made in another embodiment of the invention for the lid to have a limiting abutment preferably in the form of a rib on the inside thereof, said abutment cooperating with a limiting abutment on the inside of the filler connection likewise shaped preferably in the form of a rib formed integrally therewith. In this arrangement, the inwardly disposed abutment rib may additionally be made use of as an undercut for the closing pin of a lock which may perhaps be provided in the lid. The volume of the filler connection in accordance with the invention disposed on either side of the sheet metal of the body preferably extends approximately horizontally with a downwardly bent pipe connection adjoining said region on the inside which is connected with the filling tube or hose to the tank. In accordance with another embodiment of the invention the pipe connection is provided with a radial projection in the region of the bend, preferably in the form of a flange. The radial projection limits the passage cross sectional area of the filler connection for tank guns. It is possible to vary the passage cross sectional area selectively by simply replacing the mold core in the production of the filler connection according to the invention, in order to thus adapt the passage cross sectional area to different tank guns.
Provision is made in another embodiment of the invention for the inner portion to have two parallel discharge connections integrally formed thereat, coaxially with the axis of the outer portion. The one discharge connection is connected with the fuel tank through a line or pipe in order to vent the latter when fuel is filled in. Any fuel entrained in this venting operation is subsequently returned into the filler connection and thus into the tank, immediately. The other discharge connection is connected with the venting valve through which in case of overpressure fuel vapours and thus also fuel entrained therewith, are discharged. A suitable conduit is connected to this discharge connection leading the exiting medium to the bottom of the vehicle.
Owing to the arrangement of the discharge connections as selected and, in addition, due to the bending-off of the farthest inwardly disposed part of the pipe connection it is possible with the invention to mount the connection from the outside of the body. As already explained above, the fastening is suitably effected by means of a snapping connection. With extremely thin sheet metal members it will perhaps become necessary to provide a clamping plate to accommodate the surface pressure from inside.
With the filler connection in accordance with the invention the valve means are associated to the filler connection proper, so that the closure lid may be of a simple construction and configuration. It is furthermore possible to use only one basic housing member both for the closable and the non-closable version. The parts of the lock are preferably mounted in the center portion of the lid, in recesses already provided for this purpose. In the process of production only one mold core has to be replaced in order to make possible the break-through for the lock. As regards the valves provision is made in one embodiment of the invention for two valves to be arranged preferably side by side in the upper region of the inner portion. In this connection, provision is made in another embodiment of the invention for the discharge connection for tank venting during filling to be disposed below the valves but above the pipe connection. It is particularly advantageous if the valves in accordance with the invention comprise two housing portions one of them formed integrally with the inner portion of the filler connection. The discharge connection for the overpressure valve in this arrangement is then suitably arranged at the other housing member.
If possible, the valves will be designed in such a manner that they are formed as far as possible in the formation of the connection proper. In this connection provision is made in another embodiment of the invention for the valves to be membrane valves having a membrane element provided with an opening and a valve seat element movable in limits, preferably a ball, which may be sealingly engaged with the opening. Such a valve makes use of the favourable properties of responsiveness of a membrane valve but avoids the disadvantage of too rapid wear and contamination by the provision of a valve seat element supported for limited movement which is adapted to be brought into sealing engagement with the sealing opening in the membrane element. The movability of the valve seat due to the movable valve seat element ensures a constant cleaning of the valve seat so that even with a contaminated medium the functional safety of the valve is not impaired. A support of the valve seat element for limited movement in addition offers the advantage that a displacement of the sealing opening from the center due to manufacturing tolerances or later influences may be accommodated and cannot have any disadvantageous effects on the sealing properties. The valve housing preferably consists of two members adapted to be connected with each other, with the membrane fastened and clamped form-closedly or positively between the two housing portions. One housing portion in this arrangement preferably is formed integrally with the filler connection while the other one is fastened thereat, for instance, by welding.
With the aid of such valves one obtains exact valve controls. The valves become responsive at extremely low pressures thus avoiding any overload of the tank in case of overpressure. As regards the design and fastening of the closure lid it will still be noted that when selecting an extremely great thread for the tank cover with a small depth of impression of the body the gripping trough for the lid may be fully recessed into the connection. This clearly reduces the danger of accidents.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following, one example of embodiment of the invention will be described by way of the drawings, in which
FIG. 1 shows an enlarged sectional view of the filler connection according to FIG. 3,
FIG. 2 shows a partly sectional side view of the filler connection according to the invention,
FIG. 3 shows a rear view of the filler connection according to FIG. 2,
FIG. 4 shows a top plan view of the filler connection according to FIG. 3,
FIG. 5 shows a front view of the filler connection according to FIG. 3 with the cover removed,
FIG. 6 shows a representation of the opening in a sheet metal member for fastening the filler connection.
DESCRIPTION OF PREFERRED EMBODIMENT
The filler connection is to be explained essentially by way of FIG. 1. A filler connection is fastened in an opening 20 of a sheet metal member 21, the outer skin of a body, for example. Consequently, the filling connection is subdivided into an outer portion 22 and an inner portion 23. A closure lid 24 is screwed onto the outer portion.
The outer and inner portions 22, 23 essentially consist of two tubular members 25, 26 including between them an obtuse angle, here 135°. The tubular portion 26 possesses a flangelike abutment 27 at the outside thereof and at the free end is provided with a circumferentially extending annular nose 28. The first mentioned member serves as an abutment for a hose 29 which is pushed onto the tubular member 26 and fastened thereat by means of a tube clip 30. The nose 28 is meant to prevent a sliding-off movement in an axial direction. The hose 29 of which only a portion is shown leads to a fuel tank, which is not shown.
The outer portion possesses a sawtooth outer thread 4 and a flange 31 in the form of a conically shaped ring of a relatively small thickness which due to the elastic property of the synthetic material develops a spring effect. The radial flange 31 is disposed in close contact with the outer surface of the sheet metal member 21 via a sealing 3, while from the other side there are four radially outwardly pointing resilient cams coming into close contact thus securing the filler connection in the opening 20. The filler connection is inserted into the opening 20 from outside with the edge of the opening sliding over the ramp-like cams or noses 32 which are in this operation slightly deformed radially inwardly, until it comes to snap into the recess 33 between the flange 31 and the shoulder 32a in rear of the cam 32.
The lid 24 is recessed inwardly in the center portion thereof with a gripping portion 35 in the center slightly projecting again outwardly above the outer plane of the lid 24. The lid 24 is in addition provided with an axial flange 36 having a sawtooth inner thread formed to match the thread 4 of the filler connection portion 22. In the last course of thread of the thread formation 37 there is an elastic annular seal 38 which comes to lie essentially axially against the end face of the portion 25 of the filler connection and the respectively adjacent portions of the lid 24, in order to prevent escape of fuel in a liquid or gaseous form. As an alternative to the above or as an addition thereto, an annular seal 39 is arranged in the first course of thread which cooperates with the flange 31 in order to develop here a sufficient sealing effect between the lid 24 and the filler connection. The sealing rings 38 and 39 have a high inherent elasticity and are resistant to fuel.
The threads 4 and 37 of the filler connection portion 22 and the lid 24 are provided with a relatively large diameter so that the gripping trough 40 of the lid 24 is fully countersunk or recessed into the filling connection which in its turn does not project above the surface of the sheet 21 which is likewise provided with an inwardly recessed trough 41 adjacent the opening 20.
The lid 24 has a rib 42 integrally formed on the inside thereof which cooperates with a rib 43 on the inside of the connection portion 25 as an abutment. In the embodiment shown the lid 24 is formed in one piece and without a lock. In case a lock is incorporated, the rib 43 may be provided as an undercut for the closing journal of the lock.
In the upper region of the rear end face of the connection portion 25 there are provided two valves 44, 45. The valves 44, 45 are arranged side by side coaxially with respect to the axis of the portion 25 of the filler connection. Both valves 44, 45 are designed as membrane check valves, with the valve 44 functioning as a ventilation valve and the valve 45 as a venting valve. FIG. 1 only shows the venting valve 45 the construction of which will be described in more detail in the following. Valve 44, shown in FIG. 2, is constructed in the same manner but is arranged in an inverted sense because of the opposed function.
The valve housing consists of two halves 46, 47 of a circular outline and frustoconical cross sectional area which are interconnected by welding, for example, with overlapping flanges and clamping a membrane 48 between themselves. The housing portion 47 is formed integrally with the pipe connection while the housing portion 46 constitutes a separate shaped member having a discharge connection 2 formed integrally thereat. A hose 49 is pushed over the discharge connection 2 which leads to the lower region of the vehicle, which is not shown. The membrane 48 is provided with a central opening cooperating with a valve ball 6 which is retained to be movable in limits laterally and inwardly through a box-like recess 50. On the opposite side of the membrane 48 there is a pin 41 formed integrally with the housing 46 which limits the movement of the valve ball 6 in a direction towards the membrane opening. A coil spring 52 is arranged about the pin 51 which is supported at one end against the housing member 46 and at the other end against the membrane 48. If there is an overpressure prevailing in the fuel tank and thus in the filler connection, the medium (in this case fuel vapour and liquid fuel too) may enter through an opening 53 in the valve housing portion 47 into the right-hand valve chamber and may flow into the left-hand chamber via the opening of the membrane through the deflection thereof, and thence into the discharge connection 2. The hold-down pin 51 prevents the valve ball 6 from following the deflection of the membrane 48. The valve arrangement shown becomes responsive at lowest overpressures so that dangerous overpresssures will at any rate be avoided.
As already mentioned above the valve 44 is fitted with its sides disposed vice versa and thus makes possible ventilation of the filler connection and thus of the tank when fuel is being withdrawn with the internal combustion engine running. A discharge connection would of course not be necessary here. But it is suitably provided here as well in order to avoid easy contamination of the inlet opening 54 in the outer valve housing portion. Furthermore, it is possible here as well to convert the valve half 46 of the valve 44 into the valve half 46 of the valve by replacement of a core. FIG. 2 shows a cross sectional view of the ventilation valve 44.
Slightly above the axis of the connection member 25 there is a discharge connection 55 formed integrally therewith over which a hose line 56 is pushed leading to the fuel tank (not shown) i.e. into the interior of said tank at the uppermost point thereof, in order to guarantee venting during filling. The air and fuel entrained with it re-enter the connection portion 26 through the connection 55 and an opening 57 with a wall 58 extending normal to the axis of the connection portion 25 in the upper part and in parallel with the axis of the connection portion 26 in the lower part taking care of deflection in the direction of the axis of the connection portion 26, so that any splashing from the filler connection is avoided.
The coaxial but offset arrangement of the discharge connections 2 and 55 as well as the bend of the connection portion 26 make possible an extremely space-saving arrangement of the entire connection and insertion thereof from outside during mounting.
A flange-like radial projection 59 in the bent-off region between the connection portions 25 and 26 may selectively be provided determining the cross sectional area for the tank gun (not shown). Tank guns having a diameter exceeding that of the opening formed by the flange 59, therefore, cannot be used for filling the fuel tank.
FIG. 6 shows a representation of the configuration of the opening 20 formed in the sheet metal member 21. It is of an essentially circular configuration but provided with four circular recesses 60 in uniformly spaced circumferential arrangement cooperating with positioning projections 61 on the outer surface of the connection thus securing the connection against rotation. | 4y
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This invention relates generally to partition systems and more particularly to an improved arrangement including removable cover elements for overlying and masking the posts or uprights supporting one or more panels of an office partition system.
BACKGROUND OF THE INVENTION
Numerous partition systems have been developed allowing for the ready partitioning of work spaces particularly in offices. Conventionally, these systems comprise a plurality of rigid panels having attachment elements along their vertical edges and which cooperate with endmost and intermediate vertical uprights or support posts to fixedly retain the plurality of panels in a sturdy upright manner. By serially arranging the plurality of panels in a combination of straight line and angular disposition, an almost limitless configuration may be achieved according to the requirements of the user. Most often, the juncture between adjacent panels, at which point the support post is located, remains exposed to the user's view, and thus may be considered to provide an unsightly condition. With the present system, a cover member is provided which carries one or more fastener assemblies adapted to engage existing structure present in the area of the support post, to provide ready means for the rapid attachment or removal of the post cover members.
Removable cover elements for partition systems are generally well known. Cover members have been retained by means of Velcro strips and magnets. Such methods fail to provide a positive rigid attachment and present a problem in achieving accurate registry between a cover and the underlying partition components. U.S. Pat. No. 4,404,785 issued to McCracken et al. on Sept. 20, 1983, illustrates a removable cover member adapted to mask the support assembly normally found beneath the lower edge of a partition support post. The present invention improves upon the construction of the above McCracken et al. device by providing a removable cover intended to fully mask the area between adjacent partition panels from the top to the bottom of the post member itself.
SUMMARY OF THE INVENTION
With the present construction, a post cover is provided having a width substantially equal to the lateral distance normally existing between two adjacent panels affixed to a common support post. This cover is configured to slidably receive and retain one or more fastener assemblies constructed of resilient material with each having a pair of resilient curved arms extending from the rear of the cover. These arms are adapted to be sequentially inserted within slots of the respective slotted channels carried by the edges of two panels abutting each support post. Accordingly, it will be appreciated that the front or outer face of the cover may be curved or otherwise configured according to the angular disposition of any two adjacent panels. Thus, in the case of a straight line assembly of adjacent panels, the front face of the cover will be substantially flat while in the case of an outside angle such as 90°, 120°, or 135° formed between two adjacent panels, the respective post cover will be appropriately curved in cross section to accommodate the angular disposition of the panels and still provide the required masking of the otherwise exposed intermediate support post.
Accordingly, one of the objects of the present invention is to provide an improved post cover for partition systems including an elongated cover plate having a center portion bounded by two side flanges with one or more resilient fastener assemblies carried by the cover member adapted to engage slots provided in edge channels of the partition system.
Another object of the present invention is to provide an improved post cover for partition systems including an elongated cover plate extending the height of the support post and vertically slidably retaining a plurality of fastener assemblies removably attachable to components of the partition system.
The object of the present invention is to provide an improved post cover for partition systems including an elongated cover plate having side flanges slidably retaining a plurality of resilient fastener assemblies each provided with a pair of curved flexible arms sequentially insertable within slots provided in edge channels contained in the partition system.
Still another object of the present invention is to provide an improved post cover for partition systems including a cover plate containing a plurality of fastener assemblies with the cover plate arcuately configured to fully mask an outside angle formed by two supported panels disposed 90° to 135° with respect to one another.
With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel construction, combination and arrangement of parts hereinafter more fully illustrated and claimed, with reference being made to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial front prospective view of a partition assembly with a post cover according to the present invention, as it appears prior to installation;
FIG. 2 is a horizontal cross-sectional view, taken along the line 2--2 of FIG. 1, with the post cover fully installed;
FIG. 3 is a prospective view of one of the fastener assemblies carried by the cover;
FIG. 4 is a partial rear elevation of the cover with one of the fastener assemblies installed therein;
FIG. 5 is an enlarged horizontal sectional view of the cover with a fastener assembly installed therein; and
FIG. 6 is a partial top plan view illustrating an alternative panel disposition and post cover configuration.
Similar reference characters designate corresponding parts throughout the several figures of the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be seen to relate to a partition assembly, generally designated 1, and which includes two or more panels 2 each of substantially planar construction and adapted to be supported and retained in a vertical plane by means of an upright or support post 3 positioned intermediate the side edges 4--4 of each pair of adjacent panels 2. The panels are usually attached to the post 3 by means of hooks or other devices projecting outwardly from each panel side edge 4 and engageable with the post adjacent its top and bottom.
In the present instance, the panel side edges 4 are provided with an edge channel 5 suitably affixed thereto and including a substantially "C" shaped element having a base 6 attached to the panel side edge 4 and two side walls 7--7 further terminating in an inturned flange 8. A series of vertically elongated slots 9 are provided in each of the edge channel side walls 7 which in the past have served to provide attachment means for the mounting of appropriate arms or brackets allowing for the attachment of various partition accessories, such as shelving or bookcases. In the case of the present invention, as will be seen hereinbelow, the slotted edge channels provide attachment means for removably receiving a post cover C.
The attachment of the panel 2 to the post 3 is readily accomplished by providing a top hook 10 projecting inwardly from the upward portion of each edge channel 5 and a lower hook 11 adjacent the bottom of each edge channel. The posts 3 are preferably cylindrical and hollow and this construction readily admits the top hook 10 into the interior of the post while the lower hook 11 may engage the interior of a cup 12 attached to the bottom of the post.
From a review of FIGS. 1 and 2 of the drawings, it will be seen that when any two adjacent panels are thusly attached to an intermediate post 3, the inturned flanges 8 of the two panel edge channels are juxtaposed the periphery 12' of the post. This assembly of a post and plurality of panels may be secured by the application of a top cap 13 adapted to be secured to the upper portion of the post in a manner overlying the edge channel top hooks 10.
Usually it is desirable to support the panels 2 with their bottom edges 14 elevated with respect to the supporting floor 15. This is accomplished by means of a post support assembly 16 attached to the post cup 12 and which may allow leveling or adjustment of the vertical disposition of the post 3 to accommodate any uneveness in the support structure 15.
Covers or masking means to enclose the open space beneath the panel bottom edges 14 as well as beneath the post cup 12 are well known, as shown in the previously mentioned U.S. Pat. No. 4,404,785. Such cover members may be utilized along with the present invention such as in FIG. 1 which illustrates panel trim members beneath the panels and a post base cover 18 beneath the post and overlying the support assembly 16.
Post cover C comprises an elongated cover plate 19 constructed either of metal or suitable plastics and which includes a front wall 20 having a lateral extent which is no less than the lateral extent or diameter of the upright 3. Extending rearwardly from the edges of the front wall 20 are a pair of side walls or flanges 21--21 which from FIGS. 2 and 5 of the drawings will be seen to be slightly inclined inwardly toward one another for reasons which will become obvious hereinafter. The rear wall 22 of the cover plate 19, together with the inner surfaces 23 of the two side flanges 21 define an interior cavity 24 adapted to receive one or more fastener assemblies, generally designated 25.
Each fastener assembly 25 comprises a resilient clip member preferably formed of spring steel and including a mounting base 26 from which laterally extend, a pair of upper and lower tabs 27 and 28, respectively. The rounded ends 29 of each tab form a close sliding fit as each fastener assembly 25 is axially inserted from either end of a post cover into the interior cavity 24 thereof. It will be apparent that the dimensions of the lateral extent of the fastener tabs 27,28 are selected to ensure a close sliding fit within the cover cavity 24 adjacent the rear wall 22 thereof. Transverse displacement of the thus attached fasteners is precluded in view of the inward inclination of the two side walls 21 of the cover such that only axial sliding displacement of the fastener is possible.
Extending from the medial portion of the mounting base 26 of each fastener are a pair of laterally projecting deflectable curved arms 30--30 each terminating in a rounded end 31. The curved arms define a substantially constant radius arc extending from the fastener mounting base 26 a substantially greater distance than the upper and lower tabs 27-28 and normally abut the free edge 32 of the respective side wall 21.
Any number of fastener assemblies 25 may be carried by any one post cover C. At least two such fasteners will be called for to provide secure attachment of both ends of a cover and most often additional fasteners should be employed, depending upon the length of the cover, which will be understood to be related to the height of the associated panels 2. In any case the resilient nature of the unitary fasteners and the rounded construction of the tab ends 29 permits ready insertion of any number of fasteners from either end of the cover plate 19 and subsequent axial sliding thereof to selectively space apart the inserted fasteners.
With the fasteners 25 mounted within a cover plate 19, the ends 31 of those arms 30 projecting from one side of the cover plate are sequentially or concurrently inserted into selected ones of the slots 9 of one edge channel 5. If necessary, in order to achieve proper registry, one or more of the fasteners 25 may be axially shifted within the cover plate cavity 24. Thereafter, the remaining arms 30 projecting from the opposite side of the cover are urged into juxtaposed slots of the other edge channel 5 as the cover plate is swung inwardly.
When thusly installed, the ends 31 of all of the fastener arms will be understood to be disposed well behind the respective slots and the curved configuration of the resilient arms 30 provides a constant biasing action maintaining the free edges 32 of the cover side walls 21 in abutment with the panel edge channels 5.
The cover C' shown in FIG. 6 of the drawings comprises the same basic construction as the previously described arrangement. In this embodiment the panels 2'--2' are angularly disposed at an angle other than 180 degrees and accordingly the cover plate 40 and fastener assembly 41 are laterally enlarged and curved in cross-section to accommodate the different configuration of the exposed area between the two panel edges 4--4. At least when installed, the fastener tabs 42 will be seen to be curved to match the curvature of the inner surface 43 of the cover plate 40. The rounded ends 44 of the tabs are still retained in the area of the juncture of the inner surface 43 and the inwardly directed side walls 45 while the curved arms 46 normally rest upon the free edges 47 of the side walls 45. The attachment of the modified post cover C' is achieved in the same manner as that previously described, by the insertion of first, the fastener arms 46 projecting from one side of the post cover into selected slots 9 of one exposed edge channel 5 and second, by the insertion of the remaining curved arms 46 projecting from the other side of the post cover, into selected slots of the other exposed edge channel 5.
Inasmuch as the present invention is subject to many modifications, variations and changes in details, it is intended that all matter contained in the foregoing description or shown on the accompanying drawings, shall be interpreted as illustrative and not in a limiting sense. | 4y
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This application is a continuation of application Ser. No. 08/476,252, filed Jun. 7, 1995, which is a divisional of application Ser. No. 08/331,816, filed Oct. 31, 1994, which is a continuation-in-part of application Ser. No. 08/147,254, filed Nov. 1, 1993 now U.S. Pat. No. 5,603,081.
BACKGROUND
The present invention relates to a method for transmitting messages between mobile stations and a central switching system, and more particularly to a method for transmitting these messages using a more efficient communications link protocol over the air-interface of a cellular telephone system.
In a typical cellular radio system, a geographical area, e.g., a metropolitan area, is divided into several smaller, contiguous radio coverage areas called "cells." The cells are served by a series of fixed radio stations called "base stations." The base stations are connected to and controlled by a mobile services switching center (MSC). The MSC, in turn, is connected to the land-line (wire-line) public switched telephone network (PSTN). The telephone users (mobile subscribers) in the cellular radio system are provided with portable (hand-held), transportable (hand-carried) or mobile (car-mounted) telephone units (mobile stations) which communicate voice and/or data with the MSC through a nearby base station. The MSC switches calls between and among wire-line and mobile subscribers, controls signalling to the mobile stations, compiles billing statistics, and provides for the operation, maintenance and testing of the system.
FIG. 1 illustrates the architecture of a conventional cellular radio system built according to the Advanced Mobile Phone Service (AMPS) standard. In FIG. 1, an arbitrary geographic area is divided into a plurality of contiguous radio coverage areas, or cells, C1-C10. While the system of FIG. 1 is, for illustration purposes, shown to include only ten cells, the number of cells may be much larger in practice. Associated with and located in each of the cells C1-C10 is a base station designated as a corresponding one of a plurality of base stations B1-B10. Each of the base stations B1-B10 includes a plurality of channel units, each comprising a transmitter, a receiver and a controller, as is well known in the art.
In FIG. 1, the base stations B1-B10 are located at the center of the cells C1-C10, respectively, and are equipped with omni-directional antennas transmitting equally in all directions. In this case, all the channel units in each of the base stations B1-B10 are connected to one antenna. However, in other configurations of the cellular radio system, the base stations B1-B10 may be located near the periphery, or otherwise away from the centers of the cells C1-C10 and may illuminate the cells C1-C10 with radio signals directionally. For example, the base station may be equipped with three directional antennas, each one covering a 120-degree sector cell as shown in FIG. 2. In this case, some channel units will be connected to one antenna covering one sector cell, other channel units will be connected to another antenna covering another sector cell, and the remaining channel units will be connected to the remaining antenna covering the remaining sector cell. In FIG. 2, therefore, the base station serves three sector cells. However, it is not always necessary for three sector cells to exist and only one sector cell needs to be used to cover, for example, a road or a highway.
Returning to FIG. 1, each of the base stations B1-B10 is connected by voice and data links to an MSC 20 which is, in turn, connected to a central office (not shown) in the public switching telephone network (PSTN), or a similar facility, e.g., an integrated system digital network (ISDN). The relevant connections and transmission modes between the mobile switching center MSC 20 and the base stations B1-B10, or between the mobile switching center MSC 20 and the PSTN or ISDN, are well known to those of ordinary skill in the art and may include twisted wire pairs, coaxial cables, fiber optic cables or microwave radio channels operating in either analog or digital mode. Further, the voice and data links may either be provided by the operator or leased from a telephone company (telco).
With continuing reference to FIG. 1, a plurality of mobile stations M1-M9 may be found within the cells C1-C10. Again, while only nine mobile stations are shown in FIG. 1, the actual number of mobile stations may be much larger in practice and will generally exceed the number of base stations. Moreover, while none of the mobile stations M1-M9 may be found in some of the cells C1-C10, the presence or absence of the mobile stations M1-M9 in any particular one of the cells C1-C10 depends on the individual desires of each of the mobile subscribers who may travel from one location in a cell to another or from one cell to an adjacent or neighboring cell.
Each of the mobile stations M1-M9 includes a transmitter, a receiver, a controller and a user interface, e.g., a telephone handset, as is well known in the art. Each of the mobile stations M1-M9 is assigned a mobile identification number (MIN) which, in the United States, is a digital representation of the telephone directory number of the mobile subscriber. The MIN defines the subscription of the mobile subscriber on the radio path and is sent from the mobile station to the MSC 20 at call origination and from the MSC 20 to the mobile station at call termination. Each of the mobile stations M1-M9 is also identified by an electronic serial number (ESN) which is a factory-set, "unchangeable" number designed to protect against the unauthorized use of the mobile station. At call origination, for example, the mobile station will send the ESN to the MSC 20. The MSC 20 will compare the received ESN to a "blacklist" of the ESNs of mobile stations which have been reported to be stolen. If a match is found, the stolen mobile station will be denied access.
Each of the cells C1-C10 is allocated a subset of the radio frequency (RF) channels assigned to the entire cellular system by the concerned government authority, e.g., the Federal Communications Commission (FCC) in the United States. Each subset of RF channels is divided into several voice or speech channels which are used to carry voice conversations, and at least one paging/access or control channel which is used to carry supervisory data messages, between each of the base stations B1-B10 and the mobile stations M1-M9 in its coverage area. Each RF channel comprises a duplex channel (bi-directional radio transmission path) between the base station and the mobile station. The RF channel consists of a pair of separate frequencies, one for transmission by the base station (reception by the mobile station) and one for transmission by the mobile station (reception by the base station). Each channel unit in the base stations B1-B10 normally operates on a preselected one of the radio channels allocated to the corresponding cell, i.e., the transmitter (TX) and receiver (RX) of the channel unit are tuned to a pair of transmit and receive frequencies, respectively, which is not changed. The transceiver (TX/RX) of each mobile station M1-M9, however, may tune to any of the radio channels specified in the system.
In typical land-line systems, remote stations and control centers are connected by copper or fiber optic circuits which have a data throughput capacity and performance integrity that is generally significantly better than the data throughput capacity and performance integrity provided by an air interface in a cellular telephone system. As a result, the conciseness of overhead required to manage any selected communication link protocol for land-line systems is of secondary importance. In cellular telephone systems, an air interface communications link protocol is required in order to allow a mobile station to communicate with a cellular switching system. A communications link protocol is used to initiate and to receive cellular telephone calls.
The electromagnetic spectrum available for use by cellular telephone systems is limited and is portioned into units called channels. Individual channels are used as communication links either on a shared basis or on a dedicated or reserved basis. When individual channels are used as communication links on a shared basis, multiple mobile stations may either listen to or contend for the same channels. In the contending situation, each shared channel can be used by a plurality of mobile stations which compete to obtain exclusive use of the channel for a limited period of time. On the other hand, when individual channels are used as communication links on a dedicated basis, a single mobile station is assigned the exclusive use of the channel for as long as it needs it.
The continued need to serve existing analog-only mobile stations has led to the specification in IS-54B of an analog control channel (ACC) which has been inherited from the prior AMPS or the equivalent EIA/TIA-553 standard. According to EIA/TIA-553, the analog forward control channel (FOCC) on the down-link from the base station to the mobile stations carries a continuous data stream of messages (words) in the format shown in FIG. 3. Several different types (functional classes) of messages may be transmitted on the analog FOCC. These messages include a system parameter overhead message (SPOM), a global action overhead message (GAOM), a registration identification message (REGID), a mobile station control message, e.g., a paging message, and a control-filler message. The SPOM, GOAM and REGID are overhead messages which are intended for use by all mobile stations in the coverage area of the base station. Overhead messages are sent in a group called an overhead message train (OMT). The first message of each OMT must always be the SPOM which is transmitted every 0.8±0.3 seconds.
The format of the analog FOCC shown in FIG. 3 requires an idle mobile station listening to the FOCC to read all the messages transmitted in each OMT (not just paging messages) even though the information contained in these messages may not have changed from one OMT to the next OMT. This requirement tends to unnecessarily limit the mobile station battery life. One of the goals of the next generation digital cellular systems is to extend the "talk time" for the user, that is, the battery life of the mobile station. To this end, U.S. patent application Ser. No. 07/956,640 (which is incorporated here by reference) discloses a digital FOCC which can carry the types of messages specified for the analog FOCC, but in a format which allows an idle mobile station to read overhead messages when locking onto the FOCC and thereafter only when the information has changed, and to enter "sleep mode" at all other times. While in sleep mode, the mobile station turns off most internal circuitry and saves battery power.
The above-referenced U.S. patent application Ser. No. 07/956,640 shows how a digital control channel (DCC) may be defined alongside the digital traffic channels (DTC) specified in IS-54B. Referring to FIG. 4, a half-rate DCC would occupy one slot, while a full-rate DCC would occupy two slots, out of the six slots in each time-division-multiple-access (TDMA) frame of duration 40 milliseconds (msec). For additional DCC capacity, additional half-rate or full-rate DCCs may be defined in place of the DTCs until there are no more available slots on the carrier (DCCs may then be defined on another carrier if needed). Each IS-54B RF channel, therefore, can carry DTCs only, DCCs only, or a mixture of both DTCs and DCCs. Within the IS-54B framework, each RF channel can have up to three full-rate DTCs/DCCs, or six half-rate DTCs/DCCs, or any combination in-between, for example, one full-rate and four half-rate DTCs/DCCs.
In general, however, the transmission rate of the DCC need not coincide with the half-rate and full-rate specified in IS-54B, and the length of the DCC slots may not be uniform and may not coincide with the length of the DTC slots. FIG. 5 shows a general example of a forward (or downlink) DCC configured as a succession of time slots 1, 2, . . . , N, . . . included in the consecutive time slots 1, 2, . . . sent on a carrier frequency. These DCC slots may be defined on a radio channel such as that specified by IS-54B, and may consist, as seen in FIG. 5 for example, of every n-th slot in a series of consecutive slots. Each DCC slot has a duration that may or may not be 6.67 msec, which is the length of a DTC slot according to the IS-54B standard. (There are six DTC slots in each 40-msec TDMA frame.) Alternatively (and without limitation on other possible alternatives), these DCC slots may be defined in other ways known to one skilled in the art.
As shown in FIG. 5, the DCC slots may be organized into superframes and each superframe may include a number of logical channels that carry different kinds of information. One or more DCC slots may be allocated to each logical channel in the superframe. The exemplary downlink superframe in FIG. 5 includes three logical channels: a broadcast control channel (BCCH) including six successive slots for overhead messages; a paging channel (PCH) including one slot for paging messages; and an access response channel (ARCH) including one slot for channel assignment and other messages. The remaining time slots in the exemplary superframe of FIG. 5 may be dedicated to other logical channels, such as additional paging channels PCH or other channels. Since the number of mobile stations is usually much greater than the number of slots in the superframe, each paging slot is used for paging several mobile stations that share some unique characteristic, e.g., the last digit of the MIN.
For purposes of efficient sleep mode operation and fast cell selection, the BCCH may be divided into a number of sub-channels. U.S. patent application Ser. No. 07/956,640 discloses a BCCH structure that allows the mobile station to read a minimum amount of information when it is switched on (when it locks onto a DCC) before being able to access the system (place or receive a call). After being switched on, an idle mobile station needs to regularly monitor only its assigned PCH slots (usually one in each superframe); the mobile can sleep during other slots. The ratio of the mobile's time spent reading paging messages and its time spent asleep is controllable and represents a tradeoff between call-set-up delay and power consumption.
Since each TDMA time slot has a certain fixed information carrying capacity, each burst typically carries only a portion of a layer 3 message as noted above. In the uplink direction, multiple mobile stations attempt to communicate with the system on a contention basis, while multiple mobile stations listen for layer 3 messages sent from the system in the downlink direction. In known systems, any given layer 3 message must be carried using as many TDMA channel bursts as required to send the entire layer 3 message.
The communication link protocol is commonly referred to as a layer 2 protocol within the communications industry and its functionality includes the limiting or framing of higher level messages. Traditional layer 2 protocol framing mechanisms or bit stuffing in flag characters are commonly used in land-line networks today to frame higher layer messages, which are referred to as layer 3 messages. These layer 3 messages may be sent between communicating layer 3 peer entities residing within mobile stations and cellular switching systems.
For a better understanding of the structure and operation of the present invention, the digital control channel DCC may be divided into three layers: layer 1 (physical layer), layer 2, and layer 3. The physical layer (L1) defines the parameters of the physical communications channel, e.g., RF spacing, modulation characteristics, etc. Layer 2 (L2) defines the techniques necessary for the accurate transmission of information within the constraints of the physical channel, e.g., error correction and detection, etc. Layer 3 (L3) defines the procedures for reception and processing of information transmitted over the physical channel.
FIG. 6 schematically illustrates pluralities of layer 3 messages 11, layer 2 frames 13, and layer 1 channel bursts, or time slots, 15. In FIG. 6, each group of channel bursts corresponding to each layer 3 message may constitute a logical channel, and as described above, the channel bursts for a given layer 3 message would usually not be consecutive slots on an IS-54B carrier. On the other hand, the channel bursts could be consecutive; as soon as one time slot ends, the next time slot could begin.
Each layer 1 channel burst 15 contains a complete layer 2 frame as well as other information such as, for example, error correction information and other overhead information used for layer 1 operation. Each layer 2 frame contains at least a portion of a layer 3 message as well as overhead information used for layer 2 operation. Although not indicated in FIG. 6, each layer 3 message would include various information elements that can be considered the payload of the message, a header portion for identifying the respective message's type, and possibly padding.
Each layer 1 burst and each layer 2 frame is divided into a plurality of different fields. In particular, a limited-length DATA field in each layer 2 frame contains the layer 3 message 11. Since layer 3 messages have variable lengths depending upon the amount of information contained in the layer 3 message, a plurality of layer 2 frames may be needed for transmission of a single layer 3 message. As a result, a plurality of layer 1 channel bursts may also be needed to transmit the entire layer 3 message as there is a one-to-one correspondence between channel bursts and layer 2 frames.
As noted above, when more than one channel burst is required to send a layer 3 message, the several bursts are not usually consecutive bursts on the radio channel. Moreover, the several bursts are not even usually successive bursts devoted to the particular logical channel used for carrying the layer 3 message.
In light of the generally reduced data throughput capacity and performance integrity afforded by an individual channel in a channel sharing situation in a cellular telephone environment, the selection of an efficient air interface protocol to serve as the basis of the communication link becomes paramount.
Thus, there is a need for a layer 2 header which describes what is contained in the time slot, how it is contained in the time slot and how the information should be interpreted.
SUMMARY
It is an object of the present invention to provide an indication within the layer 2 protocol which indicates what is contained in a time slot, how it is contained in a time slot and how the information should be interpreted. According to one embodiment of the present invention, a method for transmitting information to a mobile station from a cellular switching system wherein a frame is divided into a plurality of sections including a header section and the header section is then coded so as to identify what is contained in the frame.
According to another embodiment of the present invention, a cellular communications system can page a mobile station using a SPACH Notification message. The SPACH Notification message asks the mobile station if it is able to receive a message and also indicates what type of message is going to be transmitted to the mobile station.
According to another embodiment of the present invention, a group identity field can be included in the SPACH layer 2 protocol. The group identity field indicates that a mobile is part of a group and enables the cellular communication system to page a plurality of mobiles with one page by including the group identity field in the SPACH layer 2 protocol. Furthermore, the SPACH layer 2 protocol can also include a go away flag which can be used to tell mobiles not to use a particular cell.
According to another embodiment of the present invention, a mobile station can distinguish between broadcast control channel BCCH slots and SPACH slots within a superframe. One way to distinguish between the different slots is to use a different cyclic redundancy check in the different type slots.
In yet another embodiment of the invention, a method for providing reserved channels in a layer 2 protocol in a cellular communication system includes the steps of providing a field in broadcast control channel overhead messages that indicates where reserved channels are located within a superframe.
According to another embodiment of the present invention, a group identity field (GID) can be included in the SPACH layer 2 protocol. The group identity field indicates that a mobile is part of a group. By using this group identity, the communication system can page the entire group using one page.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described in more detail with reference to preferred embodiments of the invention, given only by way of example, and illustrated in the accompanying drawings, in which:
FIG. 1 shows the architecture of a conventional cellular radio system;
FIG. 2 shows a three sector cell which may be used in the system shown in FIG. 1;
FIG. 3 shows the format of a forward analog control channel;
FIG. 4 shows the structure of a forward TDMA channel according to IS-54B;
FIG. 5 is a generalized view of a digital control channel having time slots which are grouped into superframes;
FIG. 6 illustrates a plurality of layer 3 messages, layer 2 frames, and layer 1 channel bursts in a communication system;
FIG. 7 illustrates a block diagram of an exemplary cellular mobile radio telephone system;
FIG. 8 illustrates the logical channels which make up the digital control channel according to one embodiment of the present invention;
FIG. 9 shows a hyperframe structure;
FIGS. 10a-10o illustrate various SPACH layer 2 protocol frames according to one embodiment of the present invention; and
FIG. 11 shows an exemplary slot format on the forward DCC.
DETAILED DESCRIPTION
Although the description hereinafter focuses on systems which comply with IS-54B, the principles of the present invention are equally applicable to a variety of wireless communication system, e.g., cellular and satellite radio system, irrespective of the particular mode of operation (analog, digital, dualmode, etc.), the access technique (FDMA, TDMA, CDMA, hybrid FDMA/TDMA/CDMA, etc.), or the architecture (macrocells, microcells, picocells, etc.). As will be appreciated by one skilled in the art, the logical channel which carries speech and/or data may be implemented in different ways at the physical channel level (layer 1). The physical channel may be, for example, a relatively narrow RF band (FDMA), a time slot on a radio frequency (TDMA), a code sequence (CDMA), or a combination of the foregoing. For purposes of the present invention, the term "channel" means any physical channel which can carry speech and/or data, and is not limited to any particular mode of operation, access technique or system architecture.
This application contains subject matter which is related to U.S. Pat. No. 5,353,332 to Raith et al., entitled "Method and Apparatus for Communication Control in a Radiotelephone System"; to U.S. patent application Ser. No. 07/956,640, entitled "Digital Control Channel," filed on Oct. 5, 1992; to U.S. patent application Ser. No. 08/047,452, entitled "Layer 2 Protocol for the Random Access Channel and the Access Response Channel," filed on Apr. 19, 1993; to U.S. patent application Ser. No. 08/147,254, entitled "A Method for Communicating in a Wireless Communication System," filed on Nov. 1, 1993; to U.S. patent application Ser. No. 07/967,027, entitled "Multi-Mode Signal Processing," filed on Oct. 27, 1992; and to U.S. patent application Ser. No. 08/140,467 entitled "A Method of Effecting Random Access in a Mobile Radio System," filed on Oct. 25, 1993. These six co-pending applications are incorporated herein by reference.
FIG. 7 represents a block diagram of an exemplary cellular mobile radiotelephone system according to one embodiment of the present invention. The system shows an exemplary base station 110 and a mobile station 120. The base station includes a control and processing unit 130 which is connected to the MSC 140 which in turn is connected to the PSTN (not illustrated). General aspects of such cellular radiotelephone systems are known in the art.
The base station 110 for a cell includes a plurality of voice channels handled by voice channel receiver 150 which is controlled by the control and processing unit 130. Also, each base station includes a control channel transceiver 160 which may be capable of handling more than one control channel. The control channel transceiver 160 is controlled by the control and processing unit 130. The control channel transceiver 160 broadcasts control information over the control channel of the base station or cell to mobiles locked to that control channel.
When the mobile 120 is in an idle mode, the mobile periodically scans the control channels of base stations like base station 110 to determine which cell to lock on or camp to. The mobile 120 receives absolute information (information about the particular cell corresponding to the control channel on which the information is being broadcast and may include the service profile of that cell, the control channel organization, and the type of cell) and relative information (generally the same kind of information as absolute information but is information concerning the characteristics of other cells) broadcast on a control channel at its voice and control channel transceiver 170. Then, the processing unit 180 evaluates the received control channel information which includes the characteristics of the candidate cells and determines which cell the mobile should lock onto. The received control channel information not only includes absolute information concerning the cell with which it is associated, but also contains relative information concerning other cells proximate to the cell which the control channel is associated.
According to the present invention, the digital control channel DCC comprises the logical channels shown in FIG. 8. The DCC logical channels include: a broadcast control channel (BCCH), comprising a fast broadcast control channel F-BCCH, an extended broadcast control channel E-BCCH, and a broadcast short-message-service control channel S-BCCH; a short-message-service/paging/access channel SPACH, comprising a point-to-point short-message-service channel (SMSCH), the paging channel (PCH), and an access response channel (ARCH); the random access control channel (RACH); and the reserved channel. The DCC slots can be organized into higher level structures called superframes as illustrated in FIG. 5, or as preferably illustrated in FIG. 9, which depicts the frame structure of a forward (base station to mobile station) DCC and shows two successive hyperframes, each of which preferably comprises a respective primary superframe and a respective secondary superframe.
Three successive superframes are illustrated in FIG. 9, each comprising a plurality of time slots that are organized as the logical channels F-BCCH, E-BCCH, S-BCCH, and SPACH. In general, one or more DCC slots may be allocated for each logical channel in the superframe. Each superframe in a forward DCC preferably includes a complete set of F-BCCH information (i.e., a set of layer 3 messages), using as many slots as are necessary, and each superframe preferably begins with a F-BCCH slot. After the F-BCCH slot or slots, the remaining slots in each superframe include one or more (or no) slots for the E-BCCH, S-BCCH, and SPACH logical channels.
The BCCH, which in the example shown in FIG. 5 is allocated six DCC slots, carries overhead messages. One of the overhead messages is used to define the end of the BCCH section within the superframe. The PCH, which is allocated one DCC slot, carries paging messages. The ARCH, which is also allocated one DCC slot, carries channel assignment and other messages. The exemplary superframe of FIG. 5 may contain other logical channels, including additional paging channels, as indicated by FIG. 9. If more than one PCH is defined, different groups of mobile stations identified by different traits may be assigned to different PCHs.
The BCCH acronym is used to refer collectively to the F-BCCH, E-BCCH, and S-BCCH logical channels. These three logical channels are used, in general, to carry generic, system-related information. The attributes of these three channels are that they are unidirectional (downlink), shared, point-to-multipoint, and unacknowledged. The fast BCCH is a logical channel used to broadcast time critical system information. The extended BCCH is a logical channel used to broadcast system information that is less critical than the information sent on the F-BCCH. The broadcast short message service S-BCCH is a logical channel that is used to broadcast short messages used for an SMS broadcast service.
The SPACH channel is a logical channel that is used to send information to specific mobile stations regarding SMS point-to-point, paging and to provide an access response channel. The SPACH channel may be considered to be further subdivided into three logical channels: SMSCH, ARCH, and PCH. The paging channel PCH is a subset of the SPACH dedicated to delivering pages and orders. The access response channel ARCH is a subset of the SPACH to which the mobile station autonomously moves upon successful completion of an access on the random access channel. The ARCH may be used to convey analog voice channel or digital traffic channel assignments or other responses to the mobile access attempt. The SMS point-to-point channel SMSCH is used to deliver short messages to specific mobile stations receiving SMS services, although the messages could also be addressed to more than one mobile. Similarly, the paging messages on the PCH may also be directed to more than one mobile. The SPACH is unidirectional (downlink), shared, and unacknowledged. The PCH is generally point-to-multipoint, in that it can be used to send paging messages to more than one mobile station, but in some circumstances the PCH is point-to-point. The ARCH and SMSCH are generally point-to-point, although messages sent on the ARCH can also be addressed to more than one mobile station.
For communication from the mobile stations to the base stations, the reverse (uplink) DCC comprises a random access channel RACH, which is used by the mobiles to request access to the system. The RACH logical channel is unidirectional, shared, point-to-point, and acknowledged. All time slots on the uplink are used for mobile access requests, either on a contention basis or on a reserved basis. Reserved-basis access is described in U.S. patent application Ser. No. 08/140,467, entitled "Method of Effecting Random Access in a Mobile Radio System", which was filed on Oct. 25, 1993, and which is incorporated in this application by reference. One feature of RACH operation is that reception of some downlink information is required, whereby mobile stations receive real-time feedback for every burst they send on the uplink. This is known as Layer 2 ARQ, or automatic repeat request, on the RACH, and may be provided by a flow of information called shared channel feedback on a downlink sub-channel.
It may be important sometimes to be able to distinguish between the BCCH slots and the SPACH slots within a superframe. For example, upon being switched on, a mobile station does not know which slots are BCCH slots and which slots are SPACH slots. The mobile station needs to find the overhead information at the beginning of the BCCH section to be able to determine its paging slot. Also, the boundary between the BCCH section and the SPACH section may have changed for a variety of reasons. For example, if a system has been using twelve slots of a thirty-two-slot superframe for the BCCH and wants to use thirteen slots for the BCCH, mobile stations assigned to the first paging slot after the BCCH slots must be informed that they should monitor another paging slot.
According to one aspect of the present invention, one way to distinguish between BCCH slots and SPACH slots is to use different cyclic redundancy check (CRC) bits in these channels. For example, the CRC bits in the Layer 2 frames sent in the BCCH slots may be inverted, while the check bits in the Layer 2 frames sent in the SPACH slots are not inverted. Thus, when a mobile reads the CRC bits, it obtains an indication of the kind of slot it has read. Using the check bits in this way is advantageous in some situations where it is necessary to re-assign a mobile station to another paging slot. The mobiles could obtain this information by decoding one or two bits that would identify the type of slot being decoded, but at a cost of reduced bandwidth. In Applicants' system, the mobile stations will recognize that something has changed when they spot the inverted CRC bits, and in response they will re-read the F-BCCH, including the new DCC structure and paging slot assignment.
Furthermore, as illustrated in FIG. 8, the DCC logical channels may include reserved channels that make the communication system more flexible: new features, services, or functions which can be used by future mobiles can be added at a later time without affecting existing mobiles. According to this embodiment of the present invention, the BCCH overhead messages include a field which indicates where the reserved channels are located in the superframe. These reserved channels have a potentially wide variety of uses, such as carrying messages specific to a system operator and/or mobile station manufacturer. While existing mobile stations may not be able to use the new features described in the reserved channels, the existing mobile stations will take the location and number of reserved slots into consideration when determining the location of their respective paging channels.
The SPACH layer 2 protocol is used whenever a TDMA burst, or time slot, is used to carry point-to-point SMS, paging, or ARCH information. A single SPACH layer 2 protocol frame is constructed so as to fit within a 125-bit envelope. An additional five bits are reserved for use as tail bits, resulting in a total of 130 bits of information carried within each slot assigned for SPACH purposes. FIGS. 10a-10o show a range of possible SPACH layer 2 protocol frames under various conditions. A summary of the possible SPACH formats is provided in the first table below. A summary of the fields comprising layer 2 protocol frames for SPACH operation is provided in the second table below.
Similar frame formats are used for all SPACH channels such that all frames have a common Header A. The contents of the Header A determine whether or not a Header B is present in any given SPACH frame. The Header A discriminates among hard page frames (containing no layer 3 information), PCH frames, ARCH frames and SMSCH frames. A Hard Triple Page frame containing three 34-bit mobile station identifications (MSIDs) can be sent on the PCH (burst usage (BU)=Hard Triple Page). A Hard Quadruple Page frame containing four 20-bit or 24-bit MSIDs can be sent on the PCH (BU=Hard Quadruple Page).
One or more L3 messages may be transmitted in one frame, or continued over many frames. It is currently preferred that MSIDs are only carried within frames where BU=PCH, ARCH or SMSCH with the burst type (BT)=Single MSID, Double MSID, Triple MSID, Quadruple MSID, or automatic retransmission request ARQ Mode BEGIN. The mobile station identity type IDT field identifies the format of all MSIDs carried within a given SPACH frame (i.e., no mixing of MSID formats is allowed). Pages carried on the PCH are preferably not allowed to continue beyond a single SPACH frame, although the protocol allows for it. All other PCH messages may continue beyond a single SPACH frame.
For non-ARQ-mode operation, the L2 SPACH protocol supports sending a single L3 message to multiple MSIDs in addition to the fixed one-to-one relationship between MSIDs and L3 messages. A Message Mapping field (MM) is used to control this aspect of the layer 2 frame operation. A valid SPACH frame requires that all L2 header information pertinent to a given L2 frame be included entirely within that frame, i.e., the L2 header from a given SPACH frame cannot wrap into another SPACH frame. An Offset Indicator field (OI) is used to allow both the completion of a previously started layer 3 message and the start of a new layer 3 message to occur within a single SPACH frame.
The following table summarizes the possible SPACH formats:
______________________________________ CAN BE SMS PCH ARCH CONTINUED______________________________________Single MSID Y Y Y YDouble MSID N Y Y YTriple MSID N Y Y YQuadruple MSID N Y Y YHard Triple Page (MIN) N Y N NHard Quadruple Page N Y N N(MINI)Continue Y Y Y YARQ Mode BEGIN Y N Y YARQ Mode CONTINUE Y N Y YGroup ID Y Y Y Y______________________________________
FIG. 10a illustrates the SPACH Header A according to one embodiment of the present invention. The SPACH Header A contains burst usage (BU) information and flags for managing mobile stations in a sleep mode. The BU field provides a high-level indication of burst usage. According to the present invention, the operation performed on each SPACH channel is not predetermined. The BU field indicates whether the burst is being used for paging, access response, or short message services. The flags indicate changes in sleep mode configuration as well as in broadcast control channel information. This header is always present in all possible SPACH frame types.
FIG. 10b illustrates the SPACH Header B according to one embodiment of the present invention. The SPACH Header B contains supplementary header information used to identify the remaining contents of the layer 2 frame. This header is present when Header A indicates a burst usage of type PCH, ARCH or SMSCH. In one alternative, the bit used for the offset indicator OI shown in FIG. 10b as part of the Header B may be used as a SPACH response mode SRM indicator, i.e., as information about the layer 2 access mode (contention or reservation) to be used in the next access attempt made by the receiving mobile station. The SRM indicator indicates how a mobile is to respond once it has received all frames associated with a given SPACH message.
FIG. 10c illustrates a Null Frame. The Null frame is sent when necessary by the cellular system when there is nothing else to be transmitted for any given SPACH burst. The Null Frame also contains a Go Away GA flag which will be described below.
FIGS. 10d, 10e illustrate a Hard Triple Page Frame and a Hard Quadruple Page Frame. A Hard Triple Page is a single frame page message containing three 34-bit MINs. A Hard Quadruple Page is a single frame page message containing four 20-bit or 24-bit MINs as determined by the mobile station identity type.
A Single MSID frame, as illustrated in FIG. 10f, is used for starting the delivery of ARCH or SMSCH L3 messages in a non-ARQ mode. In addition, this frame may also be used for sending L3 PCH messages (pages or otherwise), which are non-ARQ by definition. Page messages sent using a Single MSID frame cannot be continued into another frame.
If an ARCH or SMSCH L3 message is too long to fit into a Single MSID frame then the remaining L3 information is carried using additional CONTINUE frames or MSID frames as necessary. If a complete ARCH or SMSCH L3 message does fit within a Single MSID frame, it is padded with filler, i.e., bits having a predetermined value like zero, as necessary.
If a non-page PCH 13 message is too long to fit into Single MSID frame then the remaining L3 information is carried using additional CONTINUE frames or MSID frames as necessary. If a complete PCH L3 message does fit within a Single MSID frame, it is padded with FILLER as necessary. A Double MSID frame, as illustrated in FIG. 10g, is used for starting the delivery of two ARCH messages in a non-ARQ mode or two PCH L3 messages. The number of MSIDs is indicated in the BT field with the same IDT format used for both instances of MSID. Page messages sent using a Double MSID frame cannot be continued into another frame. FIG. 10h shows a Double MSID frame with continuation. FIG. 10i shows a CONTINUE frame. FIG. 10j shows an Offset Single MSID frame.
A Triple MSID frame, as illustrated in FIG. 10k, is used for starting the delivery of three ARCH L3 messages in a non-ARQ mode or three PCH 13 messages. The number of MSIDs is indicated in the BT field with the same mobile station identity type format used for all instances of MSID. Page messages sent using a Triple MSID frame cannot be continued into another frame. A Quadruple MSID frame is used for starting the delivery of four ARCH L3 messages in non ARQ mode or four PCH L3 messages. The number of MSIDs is indicated in the BT field with the same mobile station identity type format used for all instances of MSID. Page messages sent using a Quadruple MSID frame cannot be continued into another frame.
A CONTINUE frame, as illustrated in FIG. 10l, is used for continuation of the L3 messages which are too long to fit into the previous frame. Note that a L2 header which is specific to any given SPACH frame must always be carried entirely within that frame (i.e., the L2 header associated with a given SPACH frame is not completed by using a subsequent SPACH frame).
An ARQ Mode BEGIN frame, as illustrated in FIG. 10m, is used for starting the delivery of a L3 ARCH or SMSCH message in the ARQ mode. The ARQ Mode BEGIN frame contains only one MSID within its L2 header as well as a portion of the L3 message itself. If the L3 message is too long to fit into a single ARQ Mode BEGIN frame, then the remaining L3 information is carried using additional ARQ Mode CONTINUE frames as necessary. If the L3 message does fit within a single ARQ Mode BEGIN frame, it is padded with filler as necessary.
The PE field in conjunction with the transaction identifies TID field identifies the transaction initiated by the ARQ Mode BEGIN frame and serves to associate any subsequent ARQ Mode CONTINUE frames with this same transaction. An ARQ Mode BEGIN frame has an implicit frame number FRNO value of zero associated with it.
The ARQ Mode CONTINUE frame, as illustrated in FIG. 10n, is used for continuing a L3 ARCH or SMSCH message which is too long to fit into the previous ARQ Mode frame (BEGIN or CONTINUE). The frame number FRNO field identifies the CONTINUE frames within the context of the overall L3 message. The FRNO field value is incremented for each CONTINUE frame sent in support of a given transaction (i.e., multiple CONTINUE frames may be sent to complete the transaction initiated by the ARQ Mode BEGIN frame). The ARQ Mode Continue frame is also used to repeat any previously sent ARQ Mode CONTINUE frames received incorrectly by the mobile station.
According to one embodiment of the present invention, a group identity field (GID) can be included in the SPACH layer 2 protocol. The group identity field indicates that a mobile is part of a group. By using this group identity, the communication system can page the entire group using one page. A Group ID frame is illustrated in FIG. 10o. The Group ID frame is used for starting the delivery of ARCH or SMSCH L3 messages in a non-ARQ mode. In addition, this frame may also be used for sending L3 PCH messages (pages or otherwise), which are non-ARQ by definition. Page messages sent using a Group ID frame cannot be continued into another frame. If an ARCH or SMSCH L3 message or a non-page PCH L3 message is too long to fit into a Group ID frame, then the remaining L3 information is carried using an END frame or additional CONTINUE frames as necessary. If a complete ARCH or SMSCH L3 message or a non-page PCH L3 message does fit within a Group ID frame, it is padded with filler as necessary.
According to another embodiment of the present invention, a go-away flag GA can be included in the SPACH layer 2 protocol for example in the Null Frame illustrated in FIG. 10c. The GA flag can be used by the cellular system to indicate that the mobile stations should not attempt to use a certain cell. Fir example, this would permit a system operator to test a base station without risk of mobile stations trying to lock onto it.
The following table summarizes the SPACH Layer 2 Protocol fields:
__________________________________________________________________________ LengthField Name (bits) Values__________________________________________________________________________BU = Burst Usage 3 000 = Hard Triple Page (34 bit MSID) 001 = Hard Quad Page (20 or 24 bit MSID) 010 = PCH Burst 011 = ARCH Burst 100 = SMSCH Burst 101 = Reserved 110 = Reserved 111 = NullPCON = PCH Continuation 1 0 = No PCH Continuation 1 = PCH Continuation, ActivatedBCN = BCCH Change Notification 1 Transitions whenever there is a change in F-BCCH information.SMSN = SMS Notification 1 Transitions whenever there is a change in S-BCCH information.PFM = Paging Frame Modifier 1 0 = Use assigned PF 1 = Use one higher than assigned PFBT = Burst Type 3 000 = Single MSID Frame 001 = Double MSID Frame 010 = Triple MSID Frame 011 = Quadruple MSID Frame 100 = Continue Frame 101 = ARQ Mode Begin 110 = ARQ Mode Continue 111 = ReservedIDT = Identity Type 2 00 = 20 bit TMSI 01 = 24 bit MINI per IS-54B 10 = 34 bit MIN per IS-54B 11 = 50 bit IMSIMSID = Mobile Station Identity 20/24/34/50 20 bit TMSI 24 bit MINI 34 bit MIN 50 bit IMSIGID = Group Identity 24/34/50 24 bit MIN 1 34 bit MIN 50 bit IMSIMM = Message Mapping 1 0 = One instance of L3LI and L3DATA per instance of MSID. 1 = One instance of L3LI and L3DATA for multiple MSIDs.OI = Offset Indicator 1 0 = No message offset included. 1 = Message offset included.orSRM = SPACH Response Mode 0 = Next access attempt made on RACH to be contention-based. 1 = Next access attempt made on RACH to be reservation-based.CLI = Continuation Length Indicator 7 Number of bits remaining in the previous L3 message.GA = Go Away 1 Indicates if the cell is barred 0 = cell not barred 1 = cell barredL3LI = Layer 3 Length Indicator 8 Variable length layer 3 messages supported up to a maximum of 255 octets.L3DATA = Layer 3 Data Variable Contains a portion (some or all) of the layer 3 message having an overall length as indicated by L3LI. The portion of this field not used to carry Iayer 3 information is filled with zeros.PE = Partial Echo 7 The 7 least significant bits of the mobile station IS-54B MIN.TID = Transaction Identity 2 Indicates which ARQ mode transaction is being transmitted on the ARCH or SMSCH.FRNO = Frame Number 5 Uniquely identifies specific frames sent in support of an ARQ mode transaction.FILLER = Burst Filler Variable All filler bits are set zero.CRC = Cyclic Redundancy Code 16 Same Generator polynomial as IS- 54B (includes DVCC)__________________________________________________________________________
According to the present invention, the mobile station can be in any of a plurality of states. For example, a mobile station would be in a "start random access" state before the first unit of a message that is to be transmitted by a random access has been transmitted. The mobile station would be in a "start reserved access" state before the first unit of a message that is to be transmitted by a reservation-based access has been transmitted. The mobile station would be in a "more units" state if there are more units associated with the same access event pending for transmission. The mobile station would be in a "after last burst" state if the last unit of an access event has been transmitted. Finally, the mobile station would be in a "success" state after a message has been sent successfully.
The layer 2 protocol also provides for a plurality of flags. Forward shared control feedback (SCF) flags are used to control the reverse channel, i.e., the RACH, as noted above. These SCF flags are a BRI flag, a R/N flag, and a CPE flag that are interleaved and transmitted in two fields in each downlink slot (layer 1); the total length of the two fields is twenty-two bits. A preferred information format in the slots of the forward DCC is shown in FIG. 11. This format is substantially the same as the format used for the DTCs under the IS-54B standard, but new functionalities are accorded to the fields in each slot in accordance with Applicants' invention. In FIG. 11, the number of bits in each field is indicated above that field. The bits sent in the SYNC field are used in a conventional way to help ensure accurate reception of the CSFP and DATA fields, and the SYNC field would be the same as that of a DTC according to IS-54B and would carry a predetermined bit pattern used by the base stations to find the start of the slot. The CSFP field in each DCC slot conveys a coded superframe phase (SFP) value that enables the mobile stations to find the start of each superframe.
The busy/reserved/idle (BRI) flag is used to indicate whether the corresponding uplink RACH slot is Busy, Reserved or Idle for reserved-basis accesses, which is described in U.S. patent application Ser. No. 08/140,467. Six bits are used for these flags and the different conditions are encoded as shown in the table below:
______________________________________ BRI.sub.5 BRI.sub.4 BRI.sub.3 BRI.sub.2 BRI.sub.1 BRI.sub.0______________________________________Busy 1 1 1 1 0 0Reserved 0 0 1 1 1 1Idle 0 0 0 0 0 0______________________________________
The received/not received (R/N) flag is used to indicate whether or not the base station received the last transmitted burst. A five-times repetition code is used for encoding this flag as shown in the table below:
______________________________________ R/N.sub.4 R/N.sub.3 R/N.sub.2 R/N.sub.1 R/N.sub.0______________________________________Received 1 1 1 1 1Not Received 0 0 0 0 0______________________________________
According to the present invention, partial echo information is used to identify which mobile station was correctly received after the initial burst of random access and/or which mobile station is intended to have access to the reserved slot. For example, the seven least significant bits of an IS-54B-type MIN can be assigned as the partial echo information, and these are preferably encoded in a manner similar to the manner in which the digital verification color code (DVCC) is encoded under IS-54B, i.e., a (12,8) code, producing eleven bits of coded partial echo information.
The following table shows how the mobile decodes received flags according to the layer 2 state. Note that only the flags relevant to the layer 2 state are shown. In the "start random access" state, the BRI flag is the only relevant flag. During a multiburst message transmission, both the BRI and R/N flags are relevant. In the summary in the following table, b i is the bit value.
__________________________________________________________________________ Received/Not Received Busy/Reserved/Idle NotLayer 2 State Busy Reserved Idle Received received__________________________________________________________________________ 111100 001111 000000 11111 00000Start random access 1 #STR1## N/A N/AStart reserved Reserved IF <3 bits difference to N/A N/Aaccess Reserved flag code valueMore units Busy IF <4 bits difference to Busy flag code value 2 #STR2## 3 #STR3##After last burst Busy IF <4 bits difference to Busy flag code value 2 #STR4## 3 #STR5## The mobile station interprets a received coded partial echo value ashaving been correctly decoded if it differs by less than three bits from
A mobile station is allowed a maximum of Y+1, where Y=(0, 1, . . . , 7), transmission attempts before considering the attempt to transfer a message as a failure. The random delay period used in the mobile station after a Not Idle condition or after a transmission attempt is uniformly distributed between zero msec and 200 msec with a granularity of 6.667 msec (the duration of a time slot). A mobile station is preferably not allowed to make more than Z consecutive repetitions of an individual burst, where Z=(0, 1, . . . , 3).
According to one embodiment of the present invention, the BMI (base station, mobile switching center and interworking function) can page a mobile station by using SPACH Notification and thereby save much system bandwidth in some situations. For example, when a SPACH message is to be delivered to a mobile in the system illustrated in FIG. 1, all ten base stations would transmit it since the system would generally not know in which cell the mobile was located. If the SPACH message required a total of ten slots to transmit, 100 slots would be used by the system to send the SPACH message, ten slots per base station.
To avoid this waste, a SPACH Notification message would be broadcast in all ten cells, or whatever the appropriate number of cells for the mobile station happened to be, rather than the entire SPACH message. In essence, the SPACH Notification message asks the mobile station if it is able to receive a message. When the mobile station responds (on the RACH), the BMI can determine in which cell the mobile station is located and thus can send the SPACH message through that cell's base station.
In addition, the SPACH Notification message may also indicate what type of SPACH message will be sent to the mobile station. For example, if the mobile station receives a SPACH Notification which indicates that an SSD (Shared Secret Data) Update is coming, the mobile station issues a response containing a SPACH confirmation and starts a timer. The BMI then transmits the SSD Update Order message. Upon receipt of the message, the mobile stops the timer and enters the SSD Update Proceeding State. However, if the timer expires prior to receiving the SSD Update Order message, the mobile returns to the DCCH camping state. The SPACH Notification could also be used to notify the mobile that a SMS message is coming.
In another aspect, the system may dynamically assign temporary mobile station identities (TMSIs) to the mobile stations. Such a TMSI would be a 20-bit or 24-bit MSID sent by the system over the air interface to a mobile. The TMSI would be used by the network to page or deliver a message to the corresponding mobile station on the SPACH, and the TMSI would be used by the mobile station to make accesses on the RACH.
Using 20-bit TMSIs increases the paging capacity in comparison to using 24-bit TMSIs at the expense of reducing the address space, i.e., the number of mobiles that can be paged, in the same way that using 24-bit MSIDs increases paging capacity in comparison to using 34-bit MINs (compare FIG. 10e to FIG. 10d, for example). As seen from FIG. 10e, a single layer 2 paging frame can carry five 20-bit TMSIs, or pages, instead of four 24-bit TMSIs (or MSIDs). By providing a plurality of TMSI formats, one has the flexibility to trade off address space for paging capacity.
It is currently preferred that the BMI assign a TMSI to a mobile in response to the mobile's registration, in which case the TMSI can be provided in an information element called MSID Assignment that is included in a Registration Accept message sent on the SPACH. Advantageously, the mobile station would treat the assigned TMSI as valid until it is switched off or until it decides to carry out any of the following system accesses: a new system registration; a forced registration; a power-up registration; a TMSI timeout registration; a deregistration registration; or the first system access of any kind made after receiving various other messages, such as a registration reject message. A mobile station assigned a TMSI in a registration accept message sent by the BMI using ARQ mode advantageously would only treat the assigned TMSI as valid if the ARQ transaction were completed successfully from a layer 2 perspective.
While a particular embodiment of the present invention has been described and illustrated, it should be understood that the invention is not limited thereto since modifications may be made by persons skilled in the art. The present application contemplates any and all modifications that fall within the spirit and scope of the underlying invention disclosed and claimed herein. | 4y
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CROSS-REFERENCE TO RELATED APPLICATIONS
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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
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REFERENCE TO A "MICROFICHE APPENDIX"
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a technique for curing of photo-set resins in resin/fiber matrix composites, and particularly relates to a technique for extremely rapid, precisely controlled deep curing of resin/fiber composite parts, both during and after lay-up, using an excimer laser in seamless overlapping scans as a source of ultraviolet curing radiation.
2. Description of Related Art
In the manufacturing of thermoset and photo-set polymer-matrix composite parts, curing is the key process step that transforms the molecular structure of the composite material, stabilizing it in the desired shape. The polymer-matrix composite materials, known as resin matrix composites, include a base polymeric material that encapsulates reinforcing fibers. These composite structures are generally classified as thermoplastic resin or thermoset resin. Thermoset resin is preferred for many composite parts since they are "set" irreversibly (that is, the long-chain molecules of the polymer become cross-linked in a permanent three-dimensional arrangement) whether by heat, room-temperature chemical bonding or by ultraviolet or other photo-setting radiation. Unlike a thermoplastic resin part that can be melted down and re-shaped, the thermoset part configuration is not reversible; the resulting composite part, once cured, is very durable even when subjected to heat and chemical stress.
The reinforcing fiber may consist of glass, carbon, boron, aramid materials or other fiber, whose function is to add strength and stiffness. Many of these fiber materials are selected because of their light weight and high stiffness. These properties are especially desirable for parts in such structures as aircraft wings, automotive body panels, and high-end sporting goods. The products can range in size, from a few square inches in area for some molded parts, to tens or even hundreds of square feet for aerospace structures. The products also have a range of thickness, and are capable of achieving highly complex geometric forms including tapers and integral reinforcing structures.
An important element in the manufacturing of composite structures is a curing system that can handle large and complex parts with a high processing throughput. The curing process determines not only the ultimate performance of the product (by setting the strength of the adhesion between the fiber and the matrix and determining the final shape of the product after shrinkage) but also the economics of the entire manufacturing process through such key factors as materials cost, process cost, throughput, and yield. Throughput is usually measured as the number of units of production per day, and yield is usually measured as a percentage of the number of acceptable units per hundred units manufactured.
In many of these applications, the curing process can take several hours to complete. Furthermore, thermal stresses may arise in the composite parts during the curing operation, due to the different expansion characteristics of the composite materials and the tooling, and due to configuration complexities of the composite structures themselves. These thermal stresses may cause the part to shrink unevenly, warp, and/or retain unwanted residual stresses. Additionally, the curing process in thermoset resins initiates an exothermic reaction in the composite part, which complicates the process control. In an attempt to control the properties of the cured part and minimize the cure time, manufacturers have developed empirical `recipes,` process models, and sensor-based control systems. These methods are somewhat successful, but they are also expensive due to the trial and error process and the highly customized tooling that is required. When fabricating large structures, it is difficult to control directly the amount and rate of heat applied to the resin. It is therefore desirable to develop a large-volume, high-throughput curing system that can provide manufacturers with direct control of the curing process.
Designers of UV-based curing systems in the prior art have generally not considered how to deliver the ultraviolet radiation to initiate the curing process. The most precise controls of ultraviolet radiation have been developed for microelectronics manufacturing in which precise patterns are imaged onto photoresists for patterning microelectronics products such as integrated circuits and circuit boards. This patent presents a novel, UV-based, large-area scanning system for photothermal processing of composite structures. It is based on a scan-and-repeat exposure technology that allows seamless curing of large composite structures by delivering UV radiation in a concentrated controlled beam.
RELATED ART
Current Curing Technologies
In this section, we present a brief review of the major curing technologies used currently in the manufacturing of composite structures. The existing approaches do not currently address all of the military and industry's needs. For example, in the applications that require thermo-setting resins, the parameters for the cure cycle need to be carefully controlled in order to induce specific chemical reactions within the polymer matrix. In this proposal, it will become clear that significant improvements can be realized through the construction of a UV-based cure system that can seamlessly cure large parts.
The existing curing systems can be classified into three general categories: (a) ovens and pressurized heating systems, (b) heated tool systems, and (c) integrated shape formation and curing systems. Each of these categories is described briefly below.
Ovens and Autoclaves
An autoclave is an oven that applies both heat and pressure for curing of composite structures. Pressure is often required for the curing process in order to consolidate the laminate, ensure proper bonding with the fibers, and to create high fiber-to-matrix volume ratios. Autoclaves typically apply 85 psi of pressure and heat up to 350° F. for curing composite materials but often exceed these values. Heat transfer to the structure being cured is achieved by the convection of pressurized gas within the autoclave. Typical structure sizes range from 2 inches to 50 feet in diameter and from 12 inches to 200 feet in length [2].
In some composite structures, the resins cure at room temperature, and only pressure is applied. Other techniques of applying pressure to the structure include placing the part inside of a flexible, plastic bag under vacuum or wrapping the part with `shrink tape.` In filament winding applications, the part is prepared by wrapping the resin-fiber combination (`prepreg`) around a core, and the resulting tension from the winding process applies the required pressure as the part is cured in a conventional oven.
In oven and autoclave systems, a uniform temperature and pressure is applied externally to the entire structure being cured. When uniform temperature and pressure is applied externally to parts of varying thickness, the result is a non-uniform gradient making it difficult to control the depth of cure. This non-uniform temperature variation also makes it extremely difficult to control the viscosity of the resin. The net result is that the design of the part is constrained whenever use of oven-based systems is considered. Other frequent problems of autoclaves and ovens include improper rates of heating, blown vacuum bags, and loss of pressure.
When ovens are used for curing large composite structures, the thermal mass that needs to be heated is so large that a long period of time is required to raise the temperature of the structure to the desired level. After the part is cured, the entire oven often needs to be reduced to room temperature before the next part can be processed. The slow rate at which the temperature rises and falls results in a significant impediment to the manufacturing throughput.
Heated Tool Systems
With integrally heated tooling, the heat required to cure the polymer matrix is provided through the tool itself. In these systems, heat is typically provided by imbedded resistive heaters or heated fluid channels within the tool. These systems are often combined with either vacuum bagging or matching molds to apply pressure to the part as it is heated. When matching molds are used to apply pressure, it is necessary to cover the part with a coating in order to facilitate removal of the part after cure. The tooling is often manufactured from steel, and wide ranges of sizes and shapes are possible.
Heated tool systems, by necessity, are comprised of materials that differ from the composites that are being cured. As a result, differential rates of thermal expansion between the part and the tool can lead to stress buildup in the part. Upon removal from the tool, the part may relax (or warp) into a lesser-stressed state. It is very difficult to predict warpage and ensure that the desired shape is maintained. This problem is exacerbated for composite materials, which often have anisotropic rates of thermal expansion.
Additional problems arise since the heat is generated from a finite number of fluid channels or electrical resistance heaters. This results in local hot or cold spots that severely limits the tool's ability to cure parts uniformly.
Integrated Shape Formation and Curing Systems
There are a variety of techniques that combine the processes for shaping and curing of composite structures. Most of these processes involve a one-sided or two-sided mold. The resin and fiber are inserted into the mold by a variety of means (injection, hand lay-up, spray-up, etc.) and then cured by either of the methods described in the two previous sections.
There are other integrated curing and shaping techniques that are also employed. In a process known as pultrusion, fibers are pulled through a resin impregnation bath and then through a long steel die which is heated. Radio frequency-induced heating has been successfully applied to speed up the rate of pulling [4]. Another technique employed by some companies uses electrical resistance heaters during automated tape lay-up in order to accelerate the curing process [5].
The significant drawback to use of integrated curing and shaping techniques is the high level of customization that is required to manufacture each type of structure. Each mold or die is unique to a particular type of composite structure making it difficult to build and test prototypes especially for large structures. This technology is also limited in the types of shapes that can be manufactured.
Limitations of Current Curing Techniques
The ideal system for curing polymer matrix composite materials should combine three key attributes: it should have the ability to handle large sizes, it should operate with high processing throughput, and it should provide direct control of the curing process. In light of these and other desirable performance features, these prior technologies fall short, as follows:
(i) Autoclave and oven curing systems cannot uniformly cure parts of varying thickness resulting in a constraint on the types of designs that can be cured with this technology.
(ii) Autoclaves and oven curing systems also have problems with improper rates of heating, blown vacuum bags, and loss of pressure.
(iii) In the use of heated tool systems, differential rates of thermal expansion between the part and the tool can lead to stress buildup in the structure. The resulting warpage of the material is exacerbated by the anisotropic rate of thermal expansion for composite structures making it difficult to control the final shape.
(iv) Heated tool systems are not able to cure parts very uniformly since the heat source consists of a finite number of imbedded heat sources.
(v) For large parts, all curing processes that involve heating develop large thermal inertias either in a steel tool or in a large volume of air. The throughput is severely limited by the time required to heat and cool the structures.
(vi) As the size of the part increases, the size of the oven or tool required to cure the part increases, leading to higher costs.
(vii) When molds are used, either for heated tool systems or integrated curing systems, a change in part size or shape necessitates the construction of a new mold. These changes can be especially costly during prototyping.
(viii) Other processes, such as pultrusion, are severely limited in the types of shapes that they can cure.
(ix) It is difficult to handle the parts during transfer from lay-up to oven-cure without causing damage; that is, the part is too unstable to be moved safely, because the uncured resin lubricates the fibers, which may move, while the resin flows or drips from the part, causing both flaws and mess.
From the above list, it is clear that all existing technologies for curing of composite parts suffer from major limitations. Ideally, whereas one desires the relative flexibility of ovens in processing different shapes, one would also like the processing speed of pultrusion without any of the other disadvantages described above. The curing technology described in this patent satisfies these objectives.
PHOTO-INITIATORS
There are certain chemical additives that are sensitive to ultraviolet radiation and serve as photo-initiators. One material that includes these photo-initiator additives is "Accuset 303." The photo-initiators serve to start exothermic curing reactions that are initiated during illumination and may continue after the illumination has stopped. Photo-initiators are commonly mixed throughout the thermoset resin and can be subject to a two-step process: after the part has been configured it is stabilized by being partially cured; after stabilization, the part can be held in process inventory for a reasonable period of time, if desired, and can subsequently be fully thermoset by heat-curing in an oven [1,9,10]. Alternatively, the resin may be fully cured through continued exposure to ultraviolet light.
Prior-Art, Large-Area, High-Throughput Patterning Technology
The newly developed curing system utilizes a seamless scanning technology using overlapping small-field scans to cure large structures. In the next section we will outline how the scanning technology works for manufacturing of microelectronic products in a lithography application.
U.S. Pat. No. 4,924,257, issued May 8, 1990, and U.S. Pat. No. 5,285,236, issued Feb. 8, 1994, show a seamless scanning technology that allows high-resolution imaging of very large substrates without the difficulties associated with other lithography techniques. It is simplest to describe the patterning technology when implemented in a projection system for use with a conventional mask, so this section will describe the seamless scanning technique when applied to projection printing. The UV-based curing system described in the next section uses the same scanning technique with only some of the hardware described in this section. The technology to be described in this section has already been experimentally demonstrated [7] and several prototype systems have been constructed for use in patterning flat-panel displays, multichip modules, and printed wiring boards.
FIG. 1, which describes the present invention, will be discussed infra. FIGS. 2-5 (prior-art) schematically illustrate the state-of-the-art in scan-and-repeat patterning systems used with a mask in a seamless, overlapping scan projection lithography application according to the previous patents identified as prior art. FIG. 2 shows a representative system. FIGS. 3 and 4 (prior-art) are useful in understanding the overlapping complementary hexagonal scans to be carried out by an apparatus such as that of FIG. 2. The substrate 10 and the mask 14 are shown in FIG. 2 rigidly held in a substrate stage 12 and a mask stage 16, respectively. Both the substrate stage and the mask stage move in synchronism, with fine precision. The illumination subsystem 18 consists of a source system 20, a relay lens 22, and beam steering optics 24. The source system is such that its effective emission plane 21 is in the shape of a regular hexagon. The relay lens 22 collects radiation into a certain numerical aperture, NA, from the effective emission plane 21, and directs it with a certain magnification and numerical aperture, NA c , on the mask 14. A projection lens assembly 26, which may consist of several individual lens elements and prisms or mirrors, forms a precise image of the high-resolution pattern, contained within the illuminated hexagonal region on the mask, onto the substrate 10. The projection lens has a numerical aperture NA determined by the resolution requirements of the patterning system and is designed for as large a circular image field as possible (shown by 31 in FIG. 3). The exposure region on the substrate 10 is then defined as the largest regular hexagon (32 in FIG. 3) that can be inscribed within the above circular image field 31.
Returning to FIG. 2, the substrate stage scans across the substrate 10 so that the hexagonal exposure region traverses the length of the substrate 10 in the direction of the scan. Simultaneously, the mask stage 16 scans the mask 14 so that the hexagonal illuminated region traverses the length of the mask 14 in the direction of the scan. After completion of a scan, both stages move in a direction orthogonal to the scan direction by an amount termed the "effective scan width." Following such a lateral movement, a new scan is generated by precise movements of the substrate and mask stages in the same manner as before. The effective scan width and the illumination source system are designed with such characteristics that in combination, they produce a transition, from one scan to the next, that is totally `seamless` and free from any intensity nonuniformity. The above exposure process, thus termed a `scan-and-repeat` mechanism, is repeated until the entire substrate is exposed.
FIG. 4 illustrates the details of the mechanism of prior-art seamless hexagonal scanning. The regular hexagon 36, also shown as a-b-g-j-h-c, represents the illuminated region on the substrate at any given instant in time. The substrate is scanned across this illumination region from the right to the left. This is shown as scan 1, or 50, in FIG. 4. The orientation of the hexagon 36 is such that one of its sides, for example b-g, is orthogonal to the direction of the scan. To generate the next scan, first the substrate is moved, in a direction orthogonal to the scan direction, by a distance w (52), determined by
w=1.5l.sub.h,
where l h is the length of each side of the hexagon. (As discussed below, w is the effective scan width.) This new position of the illumination region, relative to the substrate, is 38, also shown as d-e-n-m-k-f. Now scan 2 (54), is generated by scanning the substrate, in the reverse direction, across the hexagonal illumination region 38. At the end of scan 2, the substrate is again moved by a distance w (56), the scan direction is again reversed, and scan 3 (58) is generated, and so on.
An important aspect of the above scan-and-repeat mechanism, namely the seamless overlap region between adjacent scans, may be understood as follows. First let us identify the non-overlapping regions. In scan 1, the region swept by the rectangular portion b-g-h-c of hexagon 36 is not overlapped by any portion of scan 2. Similarly, in scan 2, the region swept by the rectangular portion e-f-k-n of hexagon 38 is not overlapped by any portion of scan 1. However, the region swept by the triangular segment a-b-c of hexagon 36 in scan 1 is re-swept in scan 2 by the triangular segment d-e-f of hexagon 38. By integrating the dose received from each of the above triangular segments at any point on the substrate in the overlapping region, it can be shown that the cumulative exposure dose received anywhere in the overlapping region is the same as in the non-overlapping regions. Furthermore, the transition from scan 1 to scan 2 (and therefore the entire substrate) is seamless in exposure dose uniformity because the doses provided by hexagons 36 and 38 not only taper in opposite directions in the overlapping region, they taper to zero at apex a and apex d, respectively.
FIG. 5 shows how, in a prior art system, a laser beam, forwarded by relay lens 61, is treated by multiple reflections inside an internally-mirrored homogenizer 62. This converts the laser beam to a self-luminous light beam, with the same numerical aperture, for projection via projection lens 63.
In aggregate, this scan-and-repeat patterning system technology makes it possible to obtain seamless uniform exposure at high resolution over the entire area of a large substrate. This same scanning technology is utilized in a UV-based large area scanning system for photothermal processing of composite structures.
REFERENCES
1. MIL-HDBK-17-3E, Chapter 2, DOD Coordination Working Draft, pages 2-38-2-51 and 9-8-9-10, especially page 2-44, 1997.
2. Taricco Corporation is an example of a manufacturer of autoclaves.
3. Kalpakjian, Serope, Manufacturing Engineering and Technology, Addison-Wesley Publishing Co., Reading, Mass., 1992.
4. Strong, Brent A., Fundamentals of Composite Manufacturing, Society of Manufacturing Engineers, Dearborn, Mich., 1989.
5. An example of a company that manufactures automated tape lay-up machines is Cincinnati Milacron.
6. Jain, K., Proc. SPIE Symp. on Optical/Laser Microlithography IV, Vol.1463, p. 666, 1991; U.S. Pat. No. 4,924,257, issued May 8, 1990; and U.S. Pat. No. 5,285,236, issued Feb. 8, 1994.
7. Jain, K, et al., Proceedings 1995 International Conference on Multichip Modules, pp. 321-325, April 19-21, Denver, Colo., 1995.
8. Decker, C., Proc. SPIE Symp. Laser Assisted Processing II, vol. 1279, pp. 50-59, 1990.
9. "COMPOSITE BASICS" [online article]; available from http://www.cmicomposites.com/prodlst.htm; Internet.
10. "Resin steps up to bat, improves manufacturing process," Design News, page 41, Jan. 19, 1998.
SUMMARY OF THE INVENTION
This patent application describes a curing system that applies carefully controlled ultraviolet (UV) radiation dosages which are appropriately distributed over the entire surface of the composite part, thereby rapidly curing the material and enabling manufacturers to directly monitor the energy applied to cure the resin matrix.
This seamless scanning technology developed by Anvik Corporation and currently used in lithographic manufacturing equipment for microelectronics, has certain aspects which may also be applied for manufacturing of parts from resin matrix composites. Most of the previously designed systems require accurate control of exposure dose uniformity, but as applied to remarkably flat, thin and smooth substrate surface films which are presented at a fixed focus distance. The films are typically photoresist films, which have well-known and repeatable physical characteristics, are essentially two-dimensional, and are not subject to any exothermic reactions during or following illumination. Illumination for initiating the UV-curing process, on the other hand, must be controllable to provide a uniform dose over the entire surface of a simple-geometry part, or, alternatively, must be controllable to provide different levels of exposure that are geometry-specific for different portions of a complex-geometry part.
This invention is a breakthrough system technology that exploits the design and cost benefits of large-area, scan-and-repeat projection exposure, and, at the same time, enables the user to control very precisely the exposure dosage and, therefore, the curing rate of polymer resin matrix composite materials, for optimum part production. This system can provide high-throughput curing and very accurate control of the curing process, and can greatly increase the ease, neatness, and speed of manufacture while increasing the precision of the finished, cured part.
It is the object of the invention to provide a novel combination of apparatus and technique for carrying out complex curing operations on photo-settable resins having an ultraviolet photo-initiator, using an excimer UV laser or mercury arc lamp with seamless overlapping hexagonal scans and controls over a range of exposure conditions.
Another object is to allow forming temporary attachments among photo-settable parts of all sizes, for providing stabilization/partial curing during the shape formation, for UV-curing of variable or constant thicknesses of photo-settable resins in the same resin/fiber matrix composite part or joined set of composite parts, and for completing the cure by convection oven techniques.
Still another object of the invention is to provide precise control of the curing operation on large composite parts having varying mass of photo-set resin at varying positions.
A feature of the invention is the application of ultraviolet radiation in seamless, overlapping polygonal scans under precise control, to carry out balanced curing of photo-set resins throughout the body of the composite part.
Another feature of the invention is the advantage of complex curing capability as a result of using plural photo-initiators which are susceptible to differing wavelengths, thus allowing for selecting the time and place of attachment during a complex configuration process.
An advantage of the invention is that the curing can be carried out without the problems associated with the preparation of a wet part and its placement, while wet and unstabilized, in a convection oven for curing.
Another advantage of the invention is that, during automated tape lay-up, filament winding or other shape creating operations, concentrated UV radiation may be applied immediately following the winding for a dynamic cure to stabilize the composite part as the current layer is built up, prior to the placement of the next winding over the previously stabilized layer.
Another advantage of the invention is that the curing operation can be carried out in a combination convection oven and UV treatment station, taking full advantage of both heat-curing and UV-initiated curing.
Other objects, features and advantages of the invention will be apparent from the following written description, claims, abstract and the annexed drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a generalized schematic of a cure-initiating system, shown for use with a rotationally symmetric composite part, using a helical hexagonal scan with complementary overlaps.
FIG. 2 (Prior Art) is a diagram of a previously patented laser patterning tool now in the prior art, but useful in understanding small-field Lw illumination.
FIG. 3 (Prior Art) explains a polygon, shown as a hexagon, in the context of scan overlap for seamless exposure.
FIG. 4 (Prior Art) explains the seamless overlapping complementary polygonal scanning technique of previous patents.
FIG. 5 (Prior Art) is a diagram of an internally-mirrored homogenizer useful in converting laser radiation to self-luminous radiation for use in seamless overlapping complementary polygonal scanning of a composite part.
FIG. 6 is a schematic of a cure-initiating system for use with a rotationally symmetric object subjected to a single helical scan.
FIG. 7 is a diagram of a cure-initiating system for use with an asymmetric composite part, using a scan by moving the optics with respect to the composite part.
FIGS. 8-10 are diagrams of dosage overlaps, at seamlessness or approaching seamlessness, under a variety of conditions.
FIG. 11 shows a technique for providing a dosage of cure-initiating radiation, which may be non-equalized or equalized, on two surface areas of a single part, simultaneously.
FIG. 12 shows a technique for combining the advantages of a thermal curing oven with the advantages of high-resolution ultraviolet cure initiation.
FIG. 13 shows apparatus and technique for control of nearly seamless, appropriately non-uniform, illumination can be developed from a virtual part stored in memory, developed by scanning a marked sample part or model, developed by control feedback from markings on the actual part, developed by control feedback from dynamic sensing of thermal characteristics of the actual part during the cure-initiating illumination scan, and by various combinations, using balanced ultraviolet cure initiation for establishing a temporary attachment of a part, or thermal curing of the part.
FIG. 14 shows how control of nearly seamless, appropriately non-uniform, illumination can develop a configured part by incrementally laying up the part to form a clone of a virtual part stored in memory.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows the preferred embodiment apparatus for a ultra-violet (UV)-based, complementary overlapping hexagonal scan system for curing of resin matrix composite structures. Relative position of optics and composite part are developed by stage (S) 99, shown generalized; control module (C) 100 defines a scan of the composite part. The output of an excimer laser illumination subsystem (IS) 101 is directed into a turning mirror 102 in a scanning beam processing module 103. The scanning beam processing module 103 consists of the turning mirror 102, focusing optics 104, a beam homogenizer 105, and a condenser subsystem 106. The scanning beam processing module 103 is mounted to a large-travel translation stage 99 that is capable of moving the scanning beam processing module 103 over the entire length of the composite part 110 which is to be cured.
Inside the scanning beam processing module 103, the turning mirror 102 directs the laser beam 108 from the excimer laser in illumination subsystem 101 down towards the composite part 110 to be cured. The laser beam 108 passes through focusing optics 104 before entering beam homogenizer 105. The beam homogenizer 105 preferably is a reflective-type system based on Anvik's patented design, comprising a hexagonal light tunnel constructed from high-reflectivity dielectric mirror strips according to U.S. Pat. No. 5,828,505, OPTICAL BEAM-SHAPER-UNIFORMIZER CONSTRUCTION, serial number 08/644,773, filed May 10, 1996, Farmiga, issued Oct. 27, 1998.
In FIG. 1, similarly to FIG. 5, the beam homogenizer 105 serves to uniformize the laser beam 108 while preserving the numerical aperture determined by the focusing optics 104. The design maximizes the number of internal reflections while minimizing the overall system length, converting the output of illumination subsystem 101 to a uniform, extended light source. Furthermore, since it is an entirely reflective system, it maximizes optical efficiency by reducing optical losses.
The condenser subsystem 106 projects the output of the beam homogenizer 105 onto the surface of composite part 110. The condenser subsystem 106 is designed using off-the-shelf optical components to minimize cost and delivery delays. With the exception of the beam homogenizer 105, all of the optics in the beam processing module 103 can be fabricated from off-the-shelf components. Beneath the optical beam processing module 103 the composite part 110 is wrapped around a pre-form, such as mandrel 109. A drive motor (not shown) rotates the mandrel 109 along its axis in only one direction. The optical beam processing module 103 scans continuously at a velocity which is chosen such that, for every complete rotation of the mandrel 109, the optical beam processing module 103 moves the hexagonal beam field by the effective scan width to illuminate polygonal illumination region 107 so as to overlap previously illuminated regions. FIG. 6 shows apparatus for scanning the beam processing module in a manner which allows the entire structure to be exposed by a single, continuous, helical scan. The resulting `helix` from several rotations of the structure achieves the seamless scan. The velocity of the beam processing module 103, v t , depends on the scanning velocity, v s , as given by the expression:
V.sub.t =1.5l.sub.h v.sub.s /R
where l h is the length of the side of the illuminating hexagon, and R is the linear distance to complete one rotation of the mandrel.
Exposing the rotational composite part 110, on mandrel 109, in a continuous helical scan offers several speed and convenience advantages over the boustrophedonic (serpentine) scanning pattern. For example, at the end of each serpentine scan, the beam processing module 103 must decelerate to a halt, then reverse direction, and accelerate back to the necessary scanning velocity before the composite structure can enter the object field of the condenser subsystem 106. The acceleration and deceleration occur while the optical beam processing module 103 steps in the orthogonal direction so that the two adjacent scans are separated by the effective scan width. In comparison, when the mandrel 109 is rotated as shown in FIG. 1, the throughput can be effectively increased in two ways:
(1) there is no longer any overhead associated with reversing the scanning direction; and
(2) the scanning velocity of the mandrel 109 can be significantly greater than what can be accomplished with linear stages.
The system shown in FIG. 1 is optimized for those structures that are rotationally symmetric. FIG. 7 shows another embodiment, for UV-curing of large structures or complex parts which cannot conveniently be placed on a round mandrel. Examples are aircraft wings, spacecraft structures, distribution manifolds, etc. The output of the illumination subsystem 101 is directed to an additional turning mirror 102 which is mounted on the translation stage 99 which moves the beam processing module 103 for scanning the airfoil which is complex-geometry composite part 112. The translation stage 99, not shown in detail, since X, Y, Z stage means are known, holds the beam processing module 103 and the turning mirror 102 so that the stage steps the entire assembly to scan the complex-geometry composite part 112. The beam processing module 103 scans the hexagonal beam illumination region 107 across the complex-geometry composite part 112, here shown as an airfoil. After the completion of a scan, the stage 99 steps the entire assembly by the effective scan width so that the next scan can be seamlessly joined with the images resulting from the previous scan. This serpentine, seamless scan can be employed to cover the entire complex-geometry composite part 112, whatever its shape may be.
This scanning technology can also deliver a higher dose to selected areas of the structure. There may be thickness variations in the complex-geometry composite part 112 that require higher doses in certain regions. There may also be support structures, such as ribs, which require higher doses in order to prevent induced stresses leading to warpage. There are several techniques that can be employed to vary the dose over the composite material.
FIG. 8 shows the uniform intensity that results from the seamless joining of two scans that are separated by the effective scan width w, as shown by intensity profile 118.
FIG. 9 shows how it is possible to generate an overlap region 119, smaller than the scan width, which has a higher dose than in the non-overlap regions 120. This is accomplished by deliberating choosing a step size that is smaller than the effective scan width w. Similarly, it is possible to deliver regions of smaller dose by choosing a step size that is larger than the effective scan width w.
FIG. 10 shows how it is possible to deliver higher doses 121 or lower doses 122 over swaths which are larger than the effective scan width w. Representative ways to change the dose delivered by a single scan to achieve the effect shown in FIG. 10, are as follows:
1. Decreasing the scanning velocity of the beam processing module;
2. Increasing the repetition rate of the laser; and
3. Increasing the pulse energy.
All the above techniques achieve the same result of increasing the dose delivered during a scan.
The techniques illustrated in FIGS. 8-10 all show how one can vary the dose transverse to the scan direction. It is also possible to vary the dose along the scan direction by employing similar methods, i.e., changing pulse energy, scanning speed, or repetition rate. Additionally, one may modify the fluence (energy/area) of the laser beam by changing the field size with a zooming condenser lens system. The result is a seamless exposure to photo-setting radiation, or, where desired, an exposure to photo-setting radiation which is non-uniform where additional mass or other factors suggest such an exposure to photo-setting radiation.
FIG. 11 shows a technique for providing dosages of curing radiation on two different areas simultaneously. The two areas may be opposed top and bottom surfaces of the same complex-geometry composite part 112, or may be two separate treatment areas of the same surface of complex-geometry composite part 112, as shown, but the possibilities for variations are many, including more than two beams. Illumination subsystem 101 provides the UV-radiation beam, through beam-splitter turning mirror 102-S and turning mirror 102 to both beam processing subsystem 103-1 and beam processing subsystem 103-2. The plural beam processing subsystems 103-1 and 103-2 direct their controlled radiation patterns 107-1 and 107-2, respectively, to the appropriate surface areas of complex-geometry composite part 112. This type of multiple system offers a number of additional features. The multiple different beam processing modules 103-1, 103-2, . . . 103-n can deliver different amounts of energies over identically-sized or different-sized radiation beams. This can be used for those applications where it is desirable to selectively cure certain segments of the complex-geometry composite part 112 with a higher dose than for the rest of the part. For example, if there is a seam in an airfoil, the seam may require much higher dose to cure than the rest of the airfoil. There are also applications in which it is desirable to join different parts having different composition or different mass. The joints may require additional doses of UV-curing radiation, greater than is needed for other areas.
FIG. 12 shows a UV-based curing system which has been integrated with a conventional thermal curing system such as a convection oven. There are applications where it is desirable to selectively and partially cure certain segments of a part using a UV-based process, then complete the curing process using the conventional approach. There may also be applications where it is desirable to do the partial curing by using the conventional approach and the final curing using the UV-based system. In FIG. 12 the X-Y stage, the beam processing module 103, and the beam steering systems are all enclosed within the conventional oven 113, while the illumination source 10 remains outside the enclosure of the oven where it can be more effectively operated. FIG. 12 shows how UV-curing may be used for stabilizing a complex-geometry composite part 112 inside a convection oven 113 which then is useful for completing the cure. Illumination subsystem 101 provides a beam of UV-radiation, via transparent beam port 114 and directional optics to beam processing subsystem 103, which directs the controlled radiation pattern as polygonal illumination region 107 onto complex-geometry composite part 112.
FIG. 13 shows how the UV-based curing system can be integrated with a sophisticated control system which can be used to accurately deliver the required dose according to CAD data which matches the necessary illumination parameters to the topography or internal structure of the part being cured. The scanning speed of the stage, the laser energy, the repetition rate of the laser, or some other parameter affecting the delivered dose, can be selected and combined to change, in real time, on-the-fly, as the part is being scanned. The dose, which may be deliberately non-uniform, can be varied to optimally cure the part. Control module 100 may have all necessary dosage and placement information pre-stored, to control stage 99, illumination subsystem 101, and beam processing module 103 according to such dosage and placement information. Alternatively, control module 100 may receive feedback signals from embedded thermal sensor 115 or from non-contact sensor 116, which is sensitive to a parameter such as color or temperature to provide condition-of-cure signals which control module 100 uses to update condition-of-cure information from which dosage and placement information can be recalculated. It is also possible to use non-contact sensors as simple as photocells to sense markings 123 applied to the surface of a composite part (110, 112). The externally-applied markings 123 describe the distribution and other parameters of desired photo-cure to be applied to the composite part (110, 112).
FIG. 14 shows how ultraviolet photo-setting can be applied locally to the small field where composite fiber/resin web, such as tape 117, is currently being laid up on a previous layer of resin/fiber composite, with the result that the partially-formed complex-geometry composite part 112 is sufficiently stabilized to permit the laying up of additional material without distortion or mess. The application of the ultraviolet radiation can be integrated with this automated shape formation. Tape 117 is supplied by supply reel 117-S which is most conveniently mounted on beam processing module 103, to assure proper placement of both the tape and the related stabilizing radiation field.
All of the systems described above can operate at any of a number of ultraviolet wavelengths. This flexibility can be exploited to allow different types of thermoset resins with different spectral sensitivities to be utilized in the curing of a single part. The fact that different resins may cure at different rates when exposed to the same wavelength can be used to better control the overall curing process. It is also possible to use different wavelengths when exposing a single type of resin to achieve the same effect.
BENEFITS OF THE SYSTEM
UV-scanning system for curing of composite structures. Here we summarize the major context of curing very large structures:
(i) Seamless scanning uniformly delivers the required dose over any size structure.
(ii) This system controls the depth of cure for parts of varying thickness by tailoring the optical dose delivered to the structure according to its geometry.
(iii) This technology does not contact the part, so there is no concern for contaminating the material or for inducing any mechanical stress.
(iv) There is no required heating of large thermal masses, so the processing throughput is extremely high, limited only by the power of the laser source and the speed of the scanning stage.
(v) This technology lends itself very nicely to prototyping of new structures since there is no reliance on molds or on other customized parts.
(vi) The same system can be utilized to cure both very large and very small parts, which would not be at all practical for oven-based curing systems.
(vii) For rotationally symmetric structures, the exposure speed is increased further by a continuous helical scan. The throughput is also enhanced because the scanning velocity can be significantly larger than what can be accomplished with linear translation stages for large payloads.
(viii) This system does not suffer from any of the problems that plague autoclave systems, namely: improper rates of heating; blown vacuum bags; or loss of pressure.
(ix) With its unique hexagonal illumination configuration and maximum field utilization, the system delivers high throughputs using small-size optics modules, thus keeping system costs low. The hexagonal configuration also provides significantly enhanced throughput over other curing techniques.
(x) The high-throughput, large-volume capability can be delivered with off-the-shelf optical and mechanical components, thereby eliminating the need for development of complex and expensive machines, and reducing commercialization risks. This also helps reduce system costs.
(xi) The UV-based curing technology is compatible with existing conventional curing approaches so systems can be designed which can incorporate the new UV technology with the conventional curing approaches.
(xii) The curing process can be dynamically controlled by using CAD data stored in the control system, or employing feedback information from sensors embedded within the part or optically derived from the part.
(xiii) These techniques help enable the user to control the resin-to-fiber ratio and the uniformity of that ratio over the entire part, by directly stabilizing the resin in place. This control directly affects the final properties of the cured part.
The above advantages demonstrate that the seamless scanning technology in a UV-based curing system results in an extremely versatile processing tool that can manufacture very large composite structures cost-effectively and at a high throughput. | 4y
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CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation, under 35 U.S.C. §120, of copending International Application No. PCT/EP2011/066160, filed Sep. 17, 2011, which designated the United States; this application also claims the priority, under 35 U.S.C. §119, of German Patent Application DE 10 2010 045 871.6, filed Sep. 17, 2010; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to an exhaust-gas treatment unit for an internal combustion engine, in particular a catalyst carrier body integrated into an exhaust-gas recirculation line (EGR line) of a motor vehicle engine. The invention also relates to an internal combustion engine and a motor vehicle having an integrated exhaust-gas treatment unit.
It is known for the exhaust gases of a mobile internal combustion engine to be purified of undesired constituents which pose a health concern and/or are harmful to the environment, in particular in such a way that the exhaust gases also meet the emissions requirements of future legal regulations. Retrofit systems for the treatment of the exhaust gases are desirable, inter alia, for that purpose, so that an adaptation of existing engine concepts to future exhaust-gas purification targets is made possible in a simple manner. Likewise, constant efforts are being made to integrate the exhaust-gas treatment units required for that purpose in the vehicle in a particularly effective, space-saving and inexpensive manner.
One possibility for meeting those requirements is, for example, the provision of a so-called close-coupled catalytic converter which is positioned in the direct vicinity of the internal combustion engine and, if appropriate, even partially in an engine outlet and/or a manifold inlet. An example of such a catalyst carrier body for close-coupled installation is disclosed in European Patent EP10 09 924 B1, corresponding to U.S. Pat. No. 6,660,235.
Such exhaust-gas treatment units are generally inserted into the exhaust-gas-conducting lines and are fixedly connected by a fastening device or fastener situated at the outside such as, for example, a flange and/or a collar, to the internal combustion engine and/or the exhaust line (the manifold), and positioned by using structural elements (for example screw connections) and/or weld seams. The production of such a flange/collar is cumbersome, however, so that in that case, considerable costs are incurred specifically with regard to mass production.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an exhaust gas treatment unit for an exhaust gas recirculation line and an internal combustion engine and a motor vehicle having an exhaust-gas treatment unit, which overcome the hereinafore-mentioned disadvantages and at least partially solve the highlighted problems of the heretofore-known units, engines and vehicles of this general type. In particular, it is sought to permit a space-saving and secure integration of an exhaust-gas treatment unit in the vicinity of the internal combustion engine. It is furthermore also sought to achieve an inexpensively produced and easily assembled exhaust-gas treatment unit.
With the foregoing and other objects in view there is provided, in accordance with the invention, an exhaust-gas treatment unit, comprising a substantially cylindrical exhaust-gas treatment body with a main axis and, on at least one opening side of the exhaust-gas treatment unit, at least one of the following connecting devices or connectors:
an offset crimp, compression, pinch or squeeze zone, and a shaped structure for form-locking engagement.
A form-locking connection is one which connects two elements together due to the shape of the elements themselves, as opposed to a force-locking connection, which locks the elements together by force external to the elements.
The exhaust-gas treatment unit substantially constitutes a structural unit, in the form of an auxiliary system and/or retrofit system, through which the following functions can be realized: treatment of the exhaust gas and permanent, fixed positioning in an exhaust-gas-conducting line. In this case, the function of the positioning is performed, in particular, by a (preferably one-piece) housing. The housing forms, for example, a type of (metallic) shell region which receives, and thus also provides dimensional stability to, (at least) one exhaust-gas treatment body through which the exhaust gas can flow. For this purpose, it is possible in particular for a brazed connection and/or welded connection to the exhaust-gas treatment body to be formed. In particular, a direct or immediate connection of the housing and exhaust-gas treatment body is thus realized (without, for example, an intermediate housing, mounting mats or the like).
The exhaust-gas treatment body is, in particular, a catalytically active body. The exhaust-gas treatment body may, in particular, be constructed from coiled and/or wound metallic sheet-metal foils, which may be smooth and/or structured. In this case, the sheet-metal foils are preferably disposed in such a way that a honeycomb body with a plurality of channels or ducts (running substantially parallel to one another) is formed. Furthermore, the foils have a catalytically active coating. In particular, the foils include so-called washcoat and catalytically active material applied thereto. It is preferable for the sheet-metal foils to be in direct contact with the housing and/or connected thereto.
The exhaust-gas treatment body and the housing surrounding it preferably have a substantially cylindrical form. This means, in particular, that the cross-sectional shape normal to the main axis of the exhaust-gas treatment body is substantially cylindrical. Exhaust-gas-conducting lines are in many cases cylindrical. The basic shape of the exhaust-gas treatment body may self-evidently also be adapted to other cross sections of the exhaust-gas-conducting line. The expression “substantially” thus also encompasses conventional cross sections of the exhaust-gas-conducting lines such as, for example, an oval, a polygon or the like. What is important in this case is the predominantly uniform spacing to the wall of the respective exhaust-gas-conducting line.
The main axis of the exhaust-gas treatment body is generally congruent with the main axis of a respective exhaust-gas-conducting line. This does not mean that the main axis must imperatively be congruent with the direction of the filter ducts or channels of the exhaust-gas treatment body. This rather means that the entry direction of the exhaust gas and also the exit direction of the exhaust gas are identically substantially normal to the main axis. The main axis is often congruent with the normal to the geometric center of the inlet and/or outlet surface of the exhaust-gas treatment body.
The crimp zone of the exhaust-gas treatment unit performs the task of providing the force-locking connection to an exhaust-gas-conducting line. The crimp zone is preferably formed (only) with the housing, in such a way that the axial portion of the housing is in particular not filled, or is at least not completely filled, by the exhaust-gas treatment body. The crimp zone has, in particular, an oversize in relation to the rest of the exhaust-gas treatment unit. The oversize is suitable for forming force-locking contact, or an interference fit, with the exhaust-gas-conducting line. The crimp zone is, in particular, constructed in such a way that it deforms (radially) inward (if appropriate also in the direction of the exhaust-gas treatment body), preferably without (significantly) deforming the exhaust-gas treatment body itself. In order to form the interference fit, the crimp zone may undergo both elastic and also plastic deformation. In this case, the plastic deformation is particularly preferable. With the plastic deformation, it is ensured that the friction force resulting from the elastic deformation component associated with the plastic deformation is at a maximum. The crimp zone may, however, also be constructed in such a way that a defective exhaust-gas treatment unit and/or a functional exhaust-gas treatment unit installed in a damaged structural element can be removed again with little effort and without damage to the surrounding structural elements and/or to the exhaust-gas treatment unit.
The crimp zone may be provided in a variety of embodiments. In particular, the crimp zone may take the form of a slotted spring ring, a closed temperature expansion ring and/or an elongation of the housing with a cross section which differs from the basic shape. The crimp zone may also take the form of at least one bulge of the (in particular one piece) housing. The bulge may be formed in such a way that a deformation of the bulge resulting from the installation causes little to no deformation of the rest of the housing. That is to say, in particular, that that part of the housing which is (radially and/or axially adjacently) in contact with the exhaust-gas treatment body is subjected to only little to no deformation. Such a bulge may, in particular, be formed with a spacing of up to 20 mm [millimeters], wherein it is preferable for at least 2 and very particularly preferably at most 5 bulges to be disposed on a periphery or circumference of the housing.
The crimp zone is offset with respect to the exhaust-gas treatment body. In this case, “offset” means in particular that no deformation influence or only a minor deformation influence can be exerted on the exhaust-gas treatment body, and accordingly practically only in one portion of the housing. This may be achieved, in particular, by virtue of an offset, a change in cross section, a change in shape of the cross section and/or the like being provided between the crimp zone and the exhaust-gas treatment body. Such an offset may take the form of a step, a bend, a curve (as viewed in a longitudinal section through the housing) and/or a cohesive connection, that is to say a welded connection and/or a brazed connection.
The shaped structure for form-locking engagement may, in particular, constitute a toothing which engages into a corresponding structure in the exhaust-gas-conducting line and prevents an inadvertent loosening during operation. The shaped structure (and a corresponding line structure) may be constructed in such a way that the exhaust-gas treatment unit can be removed without damage to the exhaust-gas treatment unit and/or to the exhaust-gas-conducting line, for example in the event of necessary repairs in the region of the exhaust-gas treatment unit. The shaped structure may, in particular, also be a thread, and the line structure may have a matching counterpart thread, or a thread may be formed directly into the line during assembly. The shaped structure may, however, very particularly preferably also constitute a toothing which, through elastic deformation of the shaped structure or of the respective portion of the housing, can be inserted into the corresponding structure of the exhaust-gas-conducting line. In this case, the shaped structure is considerably greater than the conventional roughnesses in the case of a housing of that type, and in particular protrudes at least 1 mm [millimeter] and particularly preferably at most 5 mm [millimeters] beyond the outer surface of the housing.
The at least one connecting device or connector is furthermore situated on at least one opening side of the exhaust-gas treatment unit. This means, in particular, that portion of the housing which adjoins an opening side. It is preferable for only a (single) crimp zone or shaped structure to be provided, which furthermore extends, in particular, only over a limited portion of the exhaust-gas treatment unit proceeding from the opening side. Through the use of the connecting device or connector, it is thus possible in particular in an assembly direction and/or disassembly direction, for an upstream and/or downstream, force-locking and/or form-locking connection to the exhaust-gas-conducting line to be formed.
Even though it is possible for both connecting devices or connectors (crimp zone and shaped structure) to be provided on a housing, a separate provision is preferable, depending on the usage situation in a housing, in order to keep the manufacturing outlay for the production process low.
In accordance with another advantageous feature of the exhaust-gas treatment unit of the invention, the at least one connecting device or connector has a cross section which differs from the substantially cylindrical exhaust-gas treatment body. The cross section may, in particular, be formed so as to effect a suitable deformation with the result of a force-locking and/or form-locking connection to an exhaust-gas-conducting line. In this case, the cross section may occasionally differ from the shape of the cylindrical exhaust-gas treatment body only in places (locally), in order to thereby further minimize the influence of the mechanical deformation on the exhaust-gas treatment body. The cross section may also differ from the shape of the exhaust-gas treatment body in such a way as to assist simple assembly. In this case, consideration should be given, in particular, to cross sections which permit the use of tools which assist an insertion with simultaneous prestressing of the crimp zone, for example. Furthermore, the cross section may have folds and similarly acting spring devices or springs over the circumference, which in assist an elastic action of the crimp zone, for example.
It is basically stated herein that the cross sections of the exhaust-gas treatment unit in the region of the exhaust-gas treatment body and in the region of the at least one connecting device or connector may differ (with regard to the circumference and/or the area and/or the overlap) by at least 2%, in particular by at least 5%. This means, in particular, that the cross section in the region of the at least one connecting device or connector has a non-circular and/or eccentric form in relation to the cross section in the region of the exhaust-gas treatment body. In this case, consideration is given in particular to combinations of radially (at least partially) protruding cross sections (circular shape, oval, polygon, racetrack shape, etc.).
In accordance with a further advantageous feature of the exhaust-gas treatment unit of the invention, the at least one connecting device or connector is disposed eccentrically with respect to the main axis. In this way, it can in particular be achieved that the exhaust-gas treatment unit bears partially without play against the exhaust-gas-conducting line. This greatly assists stability. It can also be achieved in this way that the surface which has a force-locking and/or form-locking action extends further over the portion of the exhaust-gas treatment unit. It is furthermore also possible in this way for there to be provided over the circumference of the exhaust-gas treatment unit regions which, for possible disassembly, permit an engagement of corresponding tools.
In accordance with an added advantageous feature of the exhaust-gas treatment unit of the invention, the exhaust-gas treatment unit has a housing, and the housing and the at least one connecting device or connector are formed in one piece. In this way, it is possible to avoid disadvantages in conjunction with joining connections, reworking operations and fluctuations in material characteristics between the at least one connecting device or connector and the exhaust-gas treatment unit (or the housing). It is furthermore advantageous that, in this way, no additional structural element is required. Merely an elongation of the housing, and/or under some circumstances further working of the housing by deformation in the region of the desired connecting device or connector, is then necessary.
In a further advantageous embodiment of the exhaust-gas treatment unit according to the invention, the exhaust-gas treatment unit merges in a flowing manner into the at least one connecting device or connector. This means, in particular, that the housing forms a continuous slope (for example a widening) over the entire extent of the exhaust-gas treatment unit including the at least one connecting device or connector. In this case, the housing may (in part) have the shape of a cone and/or of a single-sided cone, and/or may have a bulged form and/or outwardly curved form. This may be advantageous in particular if, in this way, the insertion of the exhaust-gas treatment unit with a crimp zone and/or shaped structure is assisted by the flowing transition to the crimp zone and/or shaped structure. In order to prevent deformation of the internally disposed exhaust-gas treatment body, both deformation portions as well as relief slots may be provided. It is advantageous, in particular, for the exhaust-gas treatment body to have no connection to those parts of the shell surface (or of the housing) which merge in a flowing manner into the crimp zone or shaped structure. This means, in particular, that those regions of the housing of the exhaust-gas treatment unit which are connected to the exhaust-gas treatment body have substantially no change in cross section over the entire extent of the exhaust-gas treatment unit.
With the objects of the invention in view, there is also provided an internal combustion engine, comprising at least one exhaust-gas treatment unit, and at least one exhaust-gas-conducting line, wherein the at least one exhaust-gas treatment unit is inserted entirely in the at least one exhaust-gas-conducting line.
The internal combustion engine is constructed as a conventional internal combustion engine and is constructed for operation with gasoline or diesel fuel. The internal combustion engine may thus be a conventional reciprocating-piston engine or plunger-piston engine (for example Otto-cycle engine or diesel engine), a rotary piston engine or a rotary engine (Wankel engine). Operation with other internal combustion engines based on a closed cycle is also conceivable. In this case, the internal combustion engine is preferably part of a motor vehicle, in particular of an automobile.
Exhaust-gas-conducting bores are provided for the expulsion of the burned mixture from the internal combustion engine. Furthermore, internal combustion engines are known in which, according to demand, a part of the (untreated) exhaust gas is recirculated again (exhaust-gas recirculation line or EGR line). The expression “exhaust-gas-conducting line” thus encompasses not only the conventional exhaust-gas-conducting bores but also the bores provided in the internal combustion engine for the intake line. It is important in this case, in particular, that these are lines (or bores, etc.) which are (at least partially and/or intermittently) traversed by exhaust gas, which are integrated into the internal combustion engine and which are formed and/or enclosed by the engine casing. The lines are thus particularly stable and may constitute a corresponding counterbearing for a crimp zone of the exhaust-gas treatment unit. This refers, in particular, to a line portion which extends through a part of the internal combustion engine, in particular in the form of a bore through the cylinder head, of an exhaust-gas-recirculating line. In particular, the respective line portion is situated, as viewed in the flow direction of the exhaust gas, upstream of any exhaust-gas cooling device that may be provided for the treatment of the exhaust gases, for example for recirculation into at least one combustion chamber of the internal combustion engine. In particular, the exhaust-gas-conducting line is formed so as to be rigid in relation to the housing of the exhaust-gas treatment unit as a whole or only in relation to the crimp zones.
The exhaust-gas treatment unit is, in particular, formed in such a way that it is received entirely by the exhaust-gas-conducting line. In other words, this also means in particular that the exhaust-gas treatment unit is completely surrounded by the exhaust-gas-conducting line without interrupting or penetrating the exhaust-gas-conducting line, wherein the exhaust-gas-conducting line has a one-piece form preferably in the entire region around the exhaust-gas treatment unit and/or has no partition, receptacle, widening, etc. running in the circumferential direction of the exhaust-gas treatment unit. This also means, in particular, that no components of the exhaust-gas treatment unit project out of the exhaust-gas-conducting line. It is thus the case firstly that the flexibility of the configuration of the exhaust-gas treatment unit in an exhaust-gas-conducting line is increased, with the line no longer being constricted in flange regions, and secondly structural modifications, cumbersome sealing devices or seals and, in particular, additional components of the exhaust-gas treatment unit can be dispensed with. Overall, the number of required construction and assembly steps is decreased.
In accordance with another advantageous feature of the internal combustion engine of the invention, the at least one exhaust-gas treatment unit can be positioned fixedly with the exhaust-gas-conducting line in a force-locking manner. In this case, the exhaust-gas treatment unit can, in particular, be positioned fixedly by an interference fit by using an oversize in relation to the exhaust-gas-conducting line. The oversize of the exhaust-gas treatment unit may either already be provided at room temperature before installation, or else may first impart its adequate force in the operating state at operating temperature. Furthermore, the oversize may also first be realized retroactively during installation by using an additional structural element such as a temperature expansion ring.
In accordance with a further advantageous feature of the internal combustion engine of the invention, the exhaust-gas treatment unit is fixed at least at one side by calking. In this case, the line wall of the exhaust-gas-conducting line is deformed at one opening side in such a way that force-locking and form-locking are generated between the exhaust-gas treatment unit and the exhaust-gas-conducting line. The fixing device or fixation is suitable, in particular, for aluminum lines, for example lines formed as a bore into an aluminum cylinder head. Further fixing may also be produced in this way, in particular in the case of conical bores, for example.
In accordance with an added advantageous feature of the internal combustion engine of the invention, at least one of the exhaust-gas treatment units provided herein corresponds to the above-described exhaust-gas treatment unit according to the invention having at least one connecting device or connector.
With the objects of the invention in view, there is concomitantly provided a motor vehicle, comprising an internal combustion engine according to the invention with at least one exhaust-gas treatment unit according to the invention.
Other features which are considered as characteristic for the invention are set forth in the appended claims, noting that the features specified individually in the claims may be combined with one another in any desired technologically expedient manner and form further embodiments of the invention.
Although the invention is illustrated and described herein as embodied in an exhaust gas treatment unit for an exhaust gas recirculation line and an internal combustion engine and a motor vehicle having an exhaust-gas treatment unit, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a diagrammatic, side-elevational view of an exhaust-gas treatment unit with a crimp zone;
FIG. 2 is a cross-sectional view of the exhaust-gas treatment unit of FIG. 1 ;
FIG. 3 is a side-elevational view of a further exhaust-gas treatment unit with an eccentric crimp zone and a deviating cross section;
FIG. 4 is a cross-sectional view of the exhaust-gas treatment unit of FIG. 3 ;
FIG. 5 is a side-elevational view of an exhaust-gas treatment unit with a flowing transition from an exhaust-gas treatment body to the crimp zone;
FIG. 6 is a cross-sectional view of the exhaust-gas treatment unit of FIG. 5 ;
FIG. 7 is a side-elevational view of an exhaust-gas treatment unit with bulges at two opening sides;
FIG. 8 is a cross-sectional view of an exhaust-gas treatment device with a bulged connecting device;
FIG. 9 is a cross-sectional view of an exhaust-gas treatment unit in an exhaust-gas-conducting line with calking;
FIG. 10 is a partly longitudinal-sectional view of an exhaust-gas treatment unit in an exhaust-gas-conducting line with a shaped structure;
FIG. 11 is a plan view of a portion of a motor vehicle having four exhaust-gas treatment units in an intake line;
FIG. 12 is a partly longitudinal-sectional view of an exhaust-gas treatment unit in an intake line;
FIG. 13 is a plan view of a portion of a motor vehicle having four exhaust-gas treatment units in the exhaust line; and
FIG. 14 is a partly longitudinal-sectional view of an exhaust-gas treatment unit in an exhaust line.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the figures of the drawings in detail and first, particularly, to FIG. 1 thereof, there is seen an exhaust-gas treatment unit 1 having a housing 15 , a (single) exhaust-gas treatment body 3 , a crimp, compression, pinch or squeeze zone 5 at one opening side 2 and a main axis 4 . The crimp zone 5 is concentric with the main axis of the exhaust-gas treatment body 3 and also has a step relative to the exhaust-gas treatment body 3 . FIG. 2 shows a plan view of the opening side 2 of the exhaust-gas treatment unit 1 and a cross section 6 of the crimp zone 5 relative to the exhaust-gas treatment body 3 of FIG. 1 . It can be seen therein that the cross section 6 corresponds to the shape of the exhaust-gas treatment body 3 . A structure composed of alternating corrugated and smooth foils wound in an S-shape is illustrated therein representatively for various honeycomb structures.
FIG. 3 shows an exhaust-gas treatment unit 1 having an exhaust-gas treatment body 3 and a crimp zone 5 which is situated on an opening side 2 of the exhaust-gas treatment unit 1 . It can be seen even in this view that the crimp zone 5 is disposed eccentrically.
FIG. 4 is a plan view showing the opening side 2 of the exhaust-gas treatment unit 1 of FIG. 3 and illustrating that the cross section 6 is disposed eccentrically with respect to the main axis 4 . It can also be seen that the cross section 6 deviates from the shape of the exhaust-gas treatment body 3 .
FIG. 5 shows an exhaust-gas treatment unit 1 having an exhaust-gas treatment body 3 and a crimp zone 5 at the opening side 2 , in which a transition from the exhaust-gas treatment body 3 to the crimp zone has a flowing or free-flowing form. Merely for clarification, a thin dashed line is shown which divides the exhaust-gas treatment body 3 from the crimp zone 5 . The main axis 4 is illustrated in FIG. 5 as being inclined, although it may also, in the case of a deviating form of the internal configuration of the exhaust-gas treatment body 3 , be plotted horizontally in relation to the illustration.
FIG. 6 is another plan view showing the opening side 2 and the cross section 6 of the exhaust-gas treatment unit 1 of FIG. 5 . It can be seen therein that the cross section 6 deviates only partially from the shape of the exhaust-gas treatment body 3 .
FIG. 7 shows an exhaust-gas treatment unit 1 having an exhaust-gas treatment body 3 and two crimp zones 5 at two respective opening sides 2 , in which a transition from the exhaust-gas treatment body 3 to the crimp zone has a flowing or free-flowing form. Merely for clarification, oval lines are shown which indicate the elevation of the crimp zone 5 in relation to the exhaust-gas treatment body 3 . In each case three bulges are formed into both crimp zones over the circumference of the exhaust-gas treatment unit 1 .
FIG. 8 shows, by way of example, a section taken along a line VIII-VIII in FIG. 7 , in the direction of the arrows, which is superposed on a planned installation situation in an exhaust-gas-conducting line 7 . It can be seen therein that the cross section 6 deviates (inwardly and outwardly) from the shape of the exhaust-gas-conducting line 7 over the entire circumference of the exhaust-gas treatment unit 1 . If the exhaust-gas treatment unit 1 is actually inserted, the housing 15 deforms in the region of the crimp zones 5 , although the exhaust-gas treatment body 3 is not significantly affected thereby.
FIG. 9 is a plan view of an opening side 2 showing the cross section 6 of an exhaust-gas treatment unit 1 pushed into an exhaust-gas-conducting line 7 in an internal combustion engine 11 . Two calking points 17 , which prevent the exhaust-gas treatment unit 1 from becoming detached, are illustrated therein by way of example.
FIG. 10 is a partly-sectional, side view showing an exhaust-gas treatment unit 1 pushed into an exhaust-gas-conducting line 7 in an internal combustion engine 11 . In this case, the exhaust-gas treatment unit 1 has an offset connecting device or connector with a shaped structure 16 . The shaped structure 16 is latched in a form-locking manner into a corresponding line structure 18 . The housing 15 bears, over the entire circumference, against the exhaust-gas-conducting line 7 , but in the region of the shaped structure 16 has a notch formation in order to ensure that the exhaust-gas treatment unit 1 can be inserted over the line structure 18 from right to left as seen in the illustration in the figure.
FIG. 11 shows a motor vehicle 10 having an internal combustion engine 11 . The internal combustion engine 11 has an exhaust line 12 which leads from a combustion chamber 14 to the outside. Furthermore, the internal combustion engine 11 also includes an air line 13 which supplies air from the outside to the combustion chamber. The air line is supplemented by an exhaust-gas-conducting line 7 through which exhaust gases coming from the exhaust line 12 and passing through an exhaust-gas recirculation line 9 are recirculated, in a mixture with air from the air line 13 , into the combustion chamber 14 . Before the exhaust-gas/air mixture can enter the combustion chamber 14 , it is purified by the exhaust-gas treatment units 1 situated upstream.
FIG. 12 shows, in detail, a configuration of the exhaust-gas treatment unit 1 in the internal combustion engine 11 or the exhaust-gas-conducting line 7 . As a result of the spacing between the exhaust-gas treatment unit 1 and the exhaust-gas-conducting line 7 , it can be seen that it is possible for only the crimp zone 5 , but not the exhaust-gas treatment body 3 , to be in contact with the exhaust-gas-conducting line, although this is not imperatively necessary. In fact, a (plastic) deformation of the crimp zone 5 may occur in such a way that the remaining region of the housing 15 is also (partially) deformed. FIG. 12 is based on the exhaust-gas treatment unit 1 in the embodiment of FIG. 3 . It can be seen that the crimp zone 5 is deformed in the installed state. A force-locking connection is thereby ensured. The section of the exhaust-gas-conducting line 7 shown in FIG. 12 may, for example, be a portion of a cylinder head of an internal combustion engine 11 . In this case, the non-illustrated exhaust-gas recirculation line 9 may be mounted by using a diagrammatically illustrated fastening device or fastener 8 (dash-dotted lines) in such a way that no retention device for an exhaust-gas treatment unit 1 according to the invention need be disposed in between.
FIG. 13 shows a motor vehicle 10 having an internal combustion engine 11 corresponding to the illustration in FIG. 11 . Contrary to FIG. 11 , the exhaust-gas treatment units 1 are disposed, as seen in the flow direction of the exhaust gas, (directly) downstream of the combustion chambers 14 . The exhaust gas is thus purified directly after the combustion.
FIG. 14 shows details of a configuration of the exhaust-gas treatment unit 1 in the exhaust-gas-conducting line 7 . The exhaust-gas treatment unit 1 of FIG. 5 has been used therein as a basis. In this case, it can be seen even more clearly that primarily the crimp zone 5 and not the exhaust-gas treatment body 3 has been deformed. In this case, the opening side 2 is simultaneously the inlet side of the exhaust gas to be purified coming from the exhaust-gas-conducting line 7 . Since the highest thermal loads, and mechanical loads resulting from the pulsation, are to be expected at that side, the configuration appears to be particularly expedient, although that is not imperatively necessary. It can also be seen in this configuration that the exhaust line 12 or an exhaust manifold can be fastened to the cylinder head of the internal combustion engine 11 without further intermediate pieces by using the diagrammatically illustrated fastening device or fastener 8 (dash-dotted lines). In this way, inter alia, the number of fitting surfaces and sealing surfaces is reduced.
The invention thus at least partially solves the technical problems highlighted in conjunction with the prior art. In particular, a device has been proposed which can be positioned fixedly in an exhaust-gas-conducting line without external retention devices. This, inter alia, simplifies assembly and increases the flexibility of the configuration of the exhaust-gas treatment unit. | 4y
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RELATED APPLICATIONS
The present application is a divisional application of pending U.S. application Ser. No. 10/673,816 filed Sep. 9, 2003 which is a continuation-in-part of U.S. application Ser. No. 10/390,529, filed Mar. 17, 2003 now U.S. Pat. No. 7,125,610 issued Oct. 24, 2006 both of which are incorporated herein by reference thereto.
BACKGROUND OF THE INVENTION
The present invention is related to an electrolyte solution for anodizing aluminum anode foil for use in electrolytic capacitors and the capacitors containing this anode foil.
We have found that low water content variations of the glycerine and orthophosphate-containing electrolytes described in U.S. Pat. No. 6,409,905, which is incorporated herein by reference thereto, may be used for the anodization of aluminum foil to voltages sufficiently high to facilitate the use of the aforementioned foil in intermediate and high voltage electrolytic capacitors.
Previously, the maximum anodizing voltage obtainable from the aqueous phosphate solutions traditionally used to anodize aluminum capacitor foil for applications requiring extreme foil stability and oxide hydration resistance was about 220 volts, as stated in U.S. Pat. No. 3,733,291. The corrosion of the foil being anodized in aqueous phosphate solutions increases with the anodizing voltage and is sufficiently severe to result in dielectric failure above about 220 volts. The corrosion by-products formed during aluminum foil anodizing in aqueous phosphate solutions must be removed from the solution via filtering, etc., or they will deposit upon the foil and anodizing tank components in amounts sufficient to interfere with the anodizing process.
The difficulties encountered with aqueous phosphate anodizing of aluminum foil for use in relatively low voltage capacitors are such that, in spite of the superior electrical stability of foil anodized in phosphate solutions, nearly all of the low voltage foil produced today is anodized in non-phosphate solutions with the exception of a relatively small amount of phosphate which may be present to help impart hydration resistance. Due to the voltage limitations of aqueous phosphate anodizing solutions mentioned above, intermediate and high voltage capacitor foils have not traditionally been anodized in aqueous phosphate solutions.
Aluminum electrolytic capacitors for use at intermediate voltages typically contain anode foil hydrated by passing the foil through a hot water bath prior to anodizing, as defined in U.S. Pat. No. 4,582,574. These capacitors are typically for use at voltages from 150 to 250 volts and contain anode foil anodized to about 200 to 350 volts. This pre-anodizing hydration step is carried out in order to reduce the amount of electric current required to form the anodic oxide dielectric layer and is normally applied to foils to be anodized to 200 volts and above, as described in U.S. Pat. No. 4,481,073. By carefully adjusting the parameters of the pre-anodizing hydration process, as described in U.S. Pat. No. 4,242,575, the hydration process may be successfully employed with foils which are anodized to voltages significantly less than 200 volts. The energy savings associated with the pre-anodizing hydration process is sufficiently great that the vast majority of aluminum foil manufactured today is processed in this manner.
The crystallinity of the anodic oxide present on aluminum anode foil is another factor directly determining the cost of the foil for a given rating of capacitor. Crystalline anodic aluminum oxide has a higher withstanding voltage per unit thickness than does amorphous anodic aluminum oxide. As a result of the higher withstanding voltage of crystalline oxide, only about 10 angstroms of crystalline oxide is required to support each volt of applied field during anodizing as compared with approximately 14 angstroms for each volt of applied field for amorphous oxide. As a result of the higher withstanding voltage of crystalline anodic aluminum oxide, the capacitance of anode foil coated with crystalline oxide may be as much as about 40% higher than anode foil anodized to the same voltage but coated with amorphous oxide.
Crystalline anodic aluminum oxide may be readily produced by anodizing aluminum anode foil in solutions containing salts of dicarboxylic acids as the primary ionogen, as described in U.S. Pat. No. 4,481,084. Anodic oxide formation in solutions of dicarboxylic acid salts (generally at 70-95° C.) may be combined with a pre-anodizing foil hydration step to achieve a very significant savings in both energy and foil consumed per unit capacitance at a given anodizing voltage.
Hydration resistance, which is an important consideration for foil used in electrolytic capacitors, may be enhanced by the inclusion of a small amount of an alpha-hydroxy carboxylic acid (such as tartaric acid or citric acid) in the anodizing electrolyte solution, as described in U.S. Pat. No. 4,481,084. The tendency of anodic aluminum oxide to absorb water, forming a variety of hydrated species having impaired dielectric properties appears to be, at least in part, a function of the hydration status of the outermost portion of the anodic oxide at the end of the anodizing process. Lilienfeld, in U.S. Pat. No. 2,826,724 states that “it is the hydration stratum of the oxide film, adjacent the film-electrolyte interface, which causes most of the power loss; and that the progressive development of hydration at the interface causes the aforesaid instability.”
Alwitt, in U.S. Pat. No. 3,733,291, describes a method of removing the residual hydration layer from the outer surface of anodized aluminum capacitor foil which has been exposed to a pre-anodizing hydration step (Alwitt refers to this as a “preboil”) prior to anodizing in order to conserve electrical energy during anodizing. Alwitt employs a dilute phosphoric acid solution, generally with a small chromate content (to inhibit corrosion), to dissolve the outer, hydration layer.
In addition to the problems associated with the residual hydration layer on anodized foil, which has been processed through a pre-anodizing hydration or preboil step prior to anodizing, there exists another potential problem with the stability of the anodic oxide grown on preboiled aluminum foil. The formation of the anodic oxide on preboiled foil takes place via a dehydration reaction in which the layer of pseudoboehmite (i.e. hydration product) is progressively dehydrated from the foil-oxide interface outward. Apparently, the dehydration does not take place through the ejection of water molecules but rather through the ejection of hydrogen ions and the liberation of oxygen gas within the body of the oxide. The liberated oxygen gas may become trapped within the anodic oxide, rendering the oxide susceptible to cracking and dielectric failure in service. This topic is treated well in the article, entitled: “Trapped Oxygen in Aluminum Oxide Films and Its Effect on Dielectric Stability”, by Walter J. Bernard and Philip G. Russell ( Journal of the Electrochemical Society , Volume 127, number 6, June 1980, pages 1256-1261).
Stevens and Shaffer describe a method of determining the concentration of oxide flaws as a function of distance from the metal-oxide interface for trapped-oxygen flaws which are exposed via thermal relaxation steps followed by re-anodizing under carefully controlled and monitored conditions (“Defects in Crystalline Anodic Aluminum”, by J. L. Stevens and J. S. Shaffer, Journal of the Electrochemical Society , volume 133, number 6, June 1986, pages 1160-1162).
Stabilization processes have been developed which tend to expose and repair trapped oxygen flaws (in anodic oxide films on preboiled foils) as well as impart hydration resistance to the oxide film. Examples of these processes are described in U.S. Pat. Nos. 4,113,579 and 4,437,946.
For maximum anodic oxide film stability on aluminum foil, it is desirable to form the anodic film in a phosphate solution and, again, for maximum stability via maximum phosphate content throughout the oxide thickness, the foil should not be preboiled prior to the anodizing process.
The skilled artisan has therefore been limited in the ability to form oxides on the anode at high voltage, particularly with phosphate incorporation into the oxide layer.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved process for anodizing aluminium.
It is another object of the present invention to provide a process for anodizing an aluminum surface at high voltage, over 220 volts, incorporating the advantages offered by phosphate in the oxide layer. This has previously been unavailable to those of ordinary skill in the art.
A particular feature of the present invention is that one variation of the electrolyte family described in U.S. Pat. No. 6,409,905, i.e, glycerine-based electrolytes containing orthophosphate as the anionic portion of the ionogen may be used to anodize aluminum foil to high voltages, for example 1000 volts. The use of these electrolytes, then, overcomes the limitations of traditional aqueous phosphate electrolytes in so far as the maximum anodizing voltage achievable with aqueous electrolytes (i.e. 220 volts, as given in U.S. Pat. No. 3,733,291) may be exceeded by many hundreds of volts. Furthermore, the use of low-water content glycerine-based, orthophosphate-containing electrolyte solutions for anodizing aluminum avoids the corrosion of the anode foil by essentially eliminating the subsequent formation of aluminum phosphate precipitates which normally occurs during the anodization.
A preferred embodiment is provided in a capacitor comprising an aluminum anode and a dielectric layer comprising phosphate doped aluminum oxide. Particularly, the anodic dielectric comprises, at least, 25%, by weight, aluminum phosphate and the capacitor manufactured therefrom is capable of withstanding greater than 250 volts.
Yet another embodiment is provided in a process for preparing a capacitor. The process comprises fabricating an aluminum plate. The plate is contacted with an anodizing solution comprising glycerine, 0.1 to 2.0%, by weight, water and 0.01 to 0.5%, by weight, orthophosphate. A voltage is applied to the aluminum plate of at least 220 volts.
Yet another embodiment is provided in process for preparing a capacitor. The process comprises fabricating a, preferably etched, aluminum plate. The plate is preferably pre-hydrated and then contacted with an anodizing solution comprising glycerine, 0.1 to 2.0%, by weight, water and 0.01 to 0.5%, by weight, orthophosphate. A voltage is applied to the aluminum plate and an initial current is determined. The voltage is maintained until a first measured current is no more than 50% of the initial current. The voltage is then increased and initial current redetermined. The increased voltage is maintained until a second measured current is no more than 50% of the redetermined initial current. The voltage increases and voltage maintenance are continued until a final voltage is achieved.
A particularly preferred embodiment is provided in a capacitor comprising an aluminum anode and a dielectric layer comprising phosphate doped aluminum oxide. The capacitor is formed by the process of: fabricating an aluminum plate; immersing the aluminum plate in hot/boiling water to produce a hydrated oxide coating on the plate; contacting the plate with an anodizing solution comprising glycerine, 0.1 to 2.0%, by weight, water and 0.01 to 0.5%, by weight, orthophosphate; applying a positive voltage to the aluminum plate and determining an initial current; maintaining the first voltage until a first measured current is no more than 50% of the initial current; increasing the voltage and redetermining the initial current; maintaining the increased voltage until a second measured current is no more than 50% of the redetermined initial current, and continuing the increasing of the voltage and maintaining the increased voltage until a final voltage is achieved.
BRIEF SUMMARY OF THE DRAWINGS
FIG. 1 is a chart illustrating CV Product as a function of Maximum 1 st Formation Voltage.
FIGS. 2-4 are charts of CV Product as a function of frequency for anodes anodized to 300 V, 550 V and 800 V respectively.
FIG. 5 is a chart of CV Product as a function of formation voltage at a frequency of 120 Hz.
FIG. 6 is a device of the present invention comprising a capacitor with an anode anodized in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The inventors of the present application have found a particular modification of the electrolytes described in U.S. Pat. No. 6,409,905 to be useful for the anodizing of aluminum foil to several hundred volts. Generally speaking, glycerine solutions of ammonium, amine, or alkali metal orthophosphate salts containing from about 0.01 wt % to about 0.5 wt % soluble orthophosphate salt and from about 0.1% to about 2.0% by weight water, more preferably about 0.1% to about 1.0% by weight water, may be successfully used to anodize aluminum foil to high voltages. Lower orthophosphate salt concentrations and higher solution resistivities are preferably used for higher anodizing voltages in accordance with the principles of aluminum anodizing which have long been established by those familiar with the art. For most high voltage applications, we have found it to be advantageous to employ dibasic potassium phosphate as the ionogen, at a preferred concentration of 0.01% to 0.1%, by weight, depending upon the maximum desired voltage.
The electrolyte soluble orthophosphate salt may be an ammonium phosphate, an alkali metal phosphate, an amine phosphate, or mixtures thereof. Suitable alkali metal salts include, but are not limited to, mono-sodium phosphate, di-potassium phosphate, and sodium potassium phosphate. Suitable ammonium salts include, but are not limited to, mono-ammonium phosphate or di-ammonium phosphate.
The solution temperature employed may be varied over a wide range, for example, from room temperature, or about 25° C., to about 125° C., but the temperature is most conveniently maintained between about 80° C. and 105° C. In this range (i.e. about 80° C. and 105° C.) the water content of the electrolyte will tend to be automatically maintained between about 0.2% and 1.0% by contact with the atmosphere through the vapor pressure of the water present and the hygroscopicity of the glycerine solvent.
It is preferable that the anode metal is placed into the anodizing solution followed by sequentially increasing the voltage stepwise with current age down prior to the next increment. The voltage increase is preferably done in increments. The maximum size of the increment is chosen to be less than that necessary to create failure in the oxide. As the resistivity of the anodizing solution increases, the maximum voltage step which can be implemented without oxide failure increases. Based on the present invention, a voltage step of less than 75 volts is preferable. Higher steps can be taken, particularly at higher voltages with high resistivity anodizing solutions, yet the time required for adequate age down increases and therefore no substantial benefit is observed. Smaller voltage increases can be employed with the disadvantage being loss of efficiency. It is most desired that the voltage increase be at least 20 volts per step to optimise the efficiency without compromising product quality. A voltage increase of about 50 volts for each step has been determined to be optimal for the present invention.
After each voltage increase the voltage is maintained until a sufficient decrease in current is realized. The more the current is allowed to decrease prior to the next voltage increase the better for efficiency of anodization yet a decrease is observed in productivity. It is preferred that the anode be maintained at voltage long enough to allow the current to decrease to less than 50% of the original current and more preferably less than 30% of the original current. The upper limit of hold time for current decrease is based on efficiency. Allowing the current to decrease to 1%, or less, of the original current is acceptable yet the loss in efficiency exceeds the advantages obtained. It is most preferred that the voltage be maintained at each step for a time sufficient to allow the current to decrease to about 10-30% of the original current. This has been determined to be an optimal condition between suitable product and manufacturing efficiency. It has been found that a decrease in current to about 20% of the original current at each voltage step is optimum to achieve superior product performance with reasonable manufacturing efficiency. The current may be allowed to decrease to a low level at the last voltage step in order to obtain a very low leakage dielectric film.
As mentioned above, the foil, if etched to increase the microscopic surface area as usually done with capacitor anode foil, should be pre-hydrated by immersion for a short time (e.g. 5 minutes) in hot or boiling water in order to produce a coating of hydrated oxide (pseudoboehmite) on the foil surface. Etched foil which is not pre-hydrated and which is anodized in the electrolytes of the present invention tends to wrinkle or warp catastrophically at an applied voltage of approximately 250 volts. We have found that the warping of the foil with increasing voltage in the electrolytes of the present invention may be almost completely prevented by the foil pre-hydration step.
The process for manufacturing stacked foil capacitors is known in the art. Etched foil coupons, suspended from process bars or held in anodizing frames, etc., are first given a pre-hydration step. The coupons are then immersed in an anodizing electrolyte of the present invention and are processed as described above.
The anodized and rinsed coupons are then ready for processing into capacitors.
The anodic dielectric layer prepared in accordance with the present invention demonstrated superior hydration resistance to those of the prior art. The hydration resistance is sufficient to essentially eliminate deterioration of the oxide which normally occurs during standing at low voltage or in an open circuit. It is a well-known technique in the art to overcome oxide deterioration by charging the capacitor to near working voltage during periods of low voltage or open circuit. This is typically referred to as a reformation charge. The necessity for a reformation charge is particularly detrimental to battery-operated devices such as medical implantable devices and the like. The reformation charge decreases the effective life of the battery due to the non-therapeutic charging of the capacitor.
A particularly preferred embodiment of the present invention is provided in FIG. 6 . In FIG. 6 , the device, generally represented at 1 , comprises an electrical circuit, 2 , which further comprises a capacitor, 3 , of the present invention. A battery, 4 , energizes the circuit to monitor, record, or provide a response through at least one lead, 6 . The battery, circuit, capacitor and lead are all in electrical contact as well known in the art of devices.
The device is any implantable medical device including particularly pace makers and heart defibrillators. The device is typically implanted in a patient and operates in a semi-self sufficient manner relying on battery charge. By incorporating a capacitor of the present invention the battery life is extended thereby extending the time that an implantable device can be employed without battery maintanence.
EXAMPLES
Example 1
FIG. 1 shows the results obtained with unetched aluminium foil coupons which were exposed to water at 95° C.±5° C. for 5 minutes prior to anodizing. These coupons were anodized in 50 volt steps in an electrolyte solution consisting of 0.05% dibasic potassium phosphate and approximately 1% water in glycerine at 95° C.±5° C. After each voltage step, the current was allowed to “age-down” to below 20% of the initial value at each voltage step before again raising the voltage. In this case the CV product of approximately 7 microfarad-volts/cm 2 is that commonly found for crystalline anodic aluminum oxide. There is no observed capacitance penalty for anodizing in the phosphate anodizing solution.
Example 2
In order to determine the relative capacitance obtained at a given voltage, most conveniently expressed as the (capacitance)×(voltage) or CV product, electrolytes of the present invention were compared to traditional anodizing electrolytes. A series of pre-hydrated aluminium coupons were etched using a traditional chloride etching process to achieve an etch structure. The etched foil was anodized to various voltages in a stepwise manner. The capacitance of each coupon was then measured and the results expressed as CV product at each anodizing voltage.
Inventive Example 2 was prepared by processing an etched aluminum foil in an electrolyte comprising about 0.01 to 0.1%, by weight potassium phosphate and glycerine with water content below about 2%, by weight. Each sample was subjected to an initial voltage, typically about 100 V, and maintained at the initial voltage to allow the current to decrease to about 20% of the initial current. The voltage was then increased by about 50 V and maintained for an age down period. The voltage was sequentially increased and held until the final voltage was achieved. When the final voltage was achieved voltage was maintained until the current was approximately 1 mA/cm 2 .
Comparative Example 3 was prepared in a manner similar to Example 3 wherein the etched aluminum foil was processed in an electrolyte comprising boric acid, water and ammonium pentaborate. Examples 2 and 3 were each subjected to 300V, 550V and 800V formation processes. The capacitance was determined and reported as a 10 cm 2 coupon capacitance value. The CV product was determined, at the formation voltage, at various frequencies. The results are contained in Table 1.
TABLE 1
Hz
100
120
1000
10000
100000
300 V
Formation
Capacitance (uF/Coupon)
Capacitance
Example 3
9.17
9.06
8.72
8.34
5.60
Example 2
10.61
10.50
9.47
8.56
5.46
CV Product (V-uF/cm2)
CV Product
Example 3
275
272
262
250
168
Example 2
318
315
284
257
164
550 V
Formation
Capacitance (uF/Coupon)
Capacitance
Example 3
4.03
4.01
3.77
3.65
2.94
Example 2
4.49
4.43
4.00
3.65
2.82
CV Product (V-uF/cm2)
CV Product
Example 3
222
221
207
201
162
Example 2
247
244
220
201
155
800 V
Formation
Capacitance (uF/Coupon)
Capacitance
Example 3
1.52
1.50
1.38
1.32
1.21
Example 2
2.29
2.26
2.02
1.85
1.54
CV Product (V-uF/cm2)
CV Product
Example 3
122
120
110
106
97
Example 2
183
181
161
148
123
The results presented in Table 1 are reproduced in graphical form in the figures. In the figures the diamonds (□) represents results obtained from Example 2 and the triangle (Δ) represent Example 3. FIGS. 2-4 contain a graphical representation of the CV Product (μF-V/cm 2 ) as a function of frequency (Hz) at 300 V, 550V and 800V respectively. In each case the improved capacitance is demonstrated for the inventive example. FIG. 5 contains a graphical representation of the CV Product (μF-V/cm 2 ) as a function of voltage (V) at a frequency of 120 Hz. The advantages of the inventive samples are clearly demonstrated to provide a higher capacitance.
The demonstrated improvement in capacitance, as represented by the CV Product represents a substantial improvement in the art. An improvement of this magnitude is typically not observed except through multiple cumulative improvements typically achieved over long periods of time. These improvements allow the formation of a capacitor which is highly resistant to the degradation associated with hydration of the oxide layer. The improved capacitor therefore allows the manufacture of devices, particularly implantable medical devices, which have extended battery life. It is well known in the art that extended battery life is a substantial benefit manifest as further miniaturization, extended periods between battery maintenance or combinations thereof both of which are a continuing demand in the art of implantable medical devices.
The foil anodized using the methods and electrolytes of the present invention are comparable in capacitance (or CV product) to commercially anodized foil having a similar etch structure. There is no penalty, so far as capacitance is concerned, associated with the anodizing method and electrolytes of the present invention and improvements can be readily demonstrated.
The invention has been described with particular emphasis on the preferred embodiments. It would be realized from the teachings herein that other embodiments, alterations, and configurations could be employed without departing from the scope of the invention which is more specifically set forth in the claims which are appended hereto. | 4y
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BACKGROUND OF THE INVENTION
The present invention relates to ink jet printing apparatus employing a plurality of printing modules. More particularly, the invention relates to calibrating the distance between pens in the pen scan direction (Y), and calibrating the displacement of nozzle arrays relative to each other in the print media index axis (X).
The design of color ink jet printers is described in the August 1988 issue of the Hewlett-Packard Journal.
The following U.S. Pat. Nos. disclose ink jet printing technology: 4,709,245, M. J. Piatt, "Ink Jet Printer for Cooperatively Printing with a Plurality of Insertable Print/Cartridges"; 4,709,246, M. J. Piatt et al., "Adjustable Print/Cartridge Ink Jet Printer"; 4,709,247, M. J. Piatt et al., "High Resolution, Print/Cartridge Ink Jet Printer"; 4,709,248, M. J. Piatt et al., "Transverse Printing Control System for Multiple Print/Cartridge Printer"; all issued Nov. 24, 1987.
SUMMARY OF THE INVENTION
Commonly assigned and concurrently filed U.S. patent application Ser. No. 07/304,980, entitled, "Inter Pen Offset Determination and Compensation in Multi-Pen Thermal Ink Jet Pen Printing Systems," by Cobbs et al., describes a highly useful invention for calibrating the distance between pens in the pen scan direction (Y), and calibrating the displacement of nozzle arrays relative to each other in the print media index axis (X).
In general, that invention employs an optical drop detector and a separate aperture plate with an opening having teeth disposed in a vernier comb-like pattern. The present invention provides inter-pen offset determination and compensation by means of a novel arrangement employing a piezoelectric drop detector provided with a punched hole pattern therein. The arrangement of the present invention has the advantages of simplicity and low cost when used in place of the optical drop detector and separate aperture plate.
In accordance with the present invention, there is provided a color alignment system for multiple pen thermal ink jet printing systems having a capability to measure tolerance-related dot placement error. This capability allows application of a correction algorithm to the drop fire timing and image data such that the highest possible quality image is produced. In the pen scan axis the pen carriage is driven at a constant velocity by means of servo control while one of the pens is firing at a constant frequency. The ink drops initially pass through an opening provided in a piezoelectric film and are not detected. When the drop stream hits the piezoelectric film at the edge of the opening, the impact causes a piezoelectric charge to be developed. At the instant of drop detect, the carriage position is read. Comparison of the position of the carriage for all pens at the instant of first drop detect provides the inter pen spacings, or distance between the pens in the pen scan direction (Y).
The displacement of nozzle arrays in the index axis direction (X) is measured by successively positioning each pen adjacent a special pattern of openings provided in the piezoelectric film and firing ink drops through the nozzle array to locate the nozzle pattern. Multiple tests per pen may be taken in one carriage pass. This operation is repeated for each pen in the carriage.
Some of the drops impact the piezoelectric film and are detected. Others pass through the special pattern of openings and are not detected by the piezoelectric drop detector. This information is mapped into the known position of each nozzle to create a pattern of detect/no detect for each of the pens. The patterns are then compared to determine relative offsets between the pens.
The algorithm for the calibration of the distance between pens in the pen scan direction, and the calibration of the displacement of the nozzle arrays in the print media index direction is employed as a correction algorithm to electronically compensate the drop fire timing and image data. This enables the multi-pen thermal ink jet printer of the present invention to accurately overlay the primary color dots, thus resulting in a high quality image being produced.
If desired, a combined wick and wiper may be provided to remove ink from the piezoelectric film by means of non-contact wicking/wiping action that conducts the ink to an absorbent collector.
BRIEF DESCRIPTION OF DRAWINGS
The foregoing and other features of the present invention can be more readily understood with reference to the following detailed description, taken in conjunction with the accompanying drawings, wherein like reference designate like structural elements, and in which:
FIG. 1 is a plan view of a portion of a thermal ink jet printer constructed in accordance with the present invention, shown broken away to illustrate the interior thereof;
FIG. 2 shows an elevation view of adjacent orifice plates greatly magnified illustrating the inter-pen spacing between nozzle arrays;
FIG. 3 is an elevation view of the pen carriage showing the integral linear position encoder and its associated code strip;
FIG. 4 is a plan view showing a pen firing ink drops toward a piezoelectric drop detector having an opening therein;
FIG. 5 is an elevation view of adjacent orifice plates greatly magnified illustrating the offset between nozzle arrays; and
FIG. 6 is an elevation view greatly magnified of a piezoelectric film having a special pattern of openings therein for calibrating pen offsets.
DETAILED DESCRIPTION
Referring now to FIG. 1, there is shown a plan view of a thermal ink jet printer 10. The printer 10 is shown broken away, and in the interior thereof there may be seen a roll or platen 11 for carrying and indexing the print media, which may be paper, overhead transparency film, or the like. A carriage 12 is mounted for movement back and forth adjacent the print zone P of the platen 11 along a guide rail 13. Mounted within the carriage 12 are five disposable print cartrides or pens 14, 15, 16, 17 and 18. There is no fixed order for the pens 14-18, but for purposes of description, it will be assumed that by way of example, pen 14 prints the color cyan, pen 15 magenta, pen 16 yellow, and pens 17 and 18 print black, although only one black pen 17 may be used, if desired. All five pens 14-18 are thermal ink jet pens employing heating of a thin-film resistor to fire a drop of ink. This technology works on the principle of drop on demand. Each pen 14-18 has a plurality of nozzles 21 (FIG. 2), and each nozzle 21 can supply a drop of ink on demand as the pen carriage 12 scans across the print media carried by the platen 11.
FIG. 2 shows an elevation view of adjacent orifice plates 20, greatly magnified, which form a part of the pens 14-18. The orifice plates 20 are shown with thirty nozzles 21 for convenience of description, although the actual number of nozzles 21 may be more or less than 30, if desired. Furthermore, the orifice plates 20 may have a different configuration than that shown, for example, long and narrow with the nozzles 21 in two rows instead of three.
This multi-pen printer 10 of the present invention has the advantage of providing faster printing speeds and more pages between replacement of disposable print cartrides or pens 14-18. The printer 10 of the present invention which employs a separate pen for each of the primary colors (pens 14, 15, 16), plus separate black pens (pens 17 and 18), has a print quality which is equal to or better than prior art printers which provide the three primary colors on a single pen.
It has been found that there exists a strong correlation between the alignment of the primary color dots and the quality of the resulting image. In the multi-pen printer of the present invention, the ability to accurately overlay the primary color dots is dependent on manufacturing tolerances in both the pens and the printer. Rather than reduce these tolerances by refining the manufacturing processes, the printer of the present invention is provided with the capability to measure tolerance-related dot placement errors. This capability allows application of a correction algorithm to the drop fire timing and image data such that the highest possible quality image is produced.
To calibrate the pens 14-18, there is provided a linear encoder 22, shown in FIGS. 3 and 4. The linear encoder 22 is a high resolution carriage position sensor with quadrature outputs, the resolution being increased by interpolating between quadrature states. The linear encoder 22 is integral to the pen carriage 12 and provides a constant output of position of the carriage 12 as the pens 14-18 are scanned back and forth along the guide rail 13.
Referring to FIG. 3, the linear encoder 22 which is integral to the carriage 12 employs as a reference a code strip 23. The code strip 23 is a long strip of duPont brand Mylar material, for example, provided with a marking of opaque lines, which may be photographically produced. Typically, the code strip 23 may have on the order of 150 lines per inch. The linear encoder 22 may be a linear optical incremental encoder module, such as model HEDS-9200 manufactured by the Optoelectronics Division of Hewlett-Packard Company. A quadrature output of typically 600 to 800 counts per inch is used to operate the motion control system. The reference signal for positioning of ink drops on the print media is generated from a single channel of the encoder 22. This eliminates any possible problem with phase errors in the encoder 22.
In prior art devices the position of the orifice plate is detected to determine distance between pens in the pen scan direction (Y). In the present invention the position of a drop of ink in the nominal plane of the print media is detected.
In FIG. 4 there is shown a plan view of the arrangement for determining distance between pens in the pen scan direction (Y). To one side of the print zone (P), a drop detector 24 is placed in the nominal plane of the print media. The drop detector 24 comprises a strip of piezoelectric film 25 which is freely suspended or mounted as a diaphragm to the base of the printer 10. The film 25 is located to be coplanar with the print zone P. The piezoelectric film 25 may be film sold under the trade name KYNAR, or the like. The piezoelectric film 25 is provided with an opening 26. Behind the opening 26 there is disposed an absorbent ink collector 27. An electrical connection 28 conducts any electric charge developed by the piezoelectric film 25 to an amplifier and microprocessor electronics (not shown).
While the carriage 12 is moving at a constant velocity from righ to left, one of the pens 14-18 is fired continuously at the rate of 2000 or more drops per second. Firing of ink drops begins at a position such that the drops initially pass through the opening 26 and are collected in the absorbent ink collector 27. When the drop stream hits the edge 30 of the opening 26, it impacts a portion of the piezoelectric film 25, causing an electric charge to be developed. At the instant of first drop detect, the encoder 22 integral with the carriage 12 is read. Similarly, a reading is obtained for each of the remaining pens 14-18. Since the carriage 12 travels at a constant velocity and the pens 14-18 are fired, in turn, at a constant frequency, the distance between the pens 14-18 in the pen scan direction (Y) is easily determined. Comparison of the carriage positions for all pens 14-18 provides the inter-pen spacings.
The resolution of the linear encoder 22 is increased by interpolating between pulses. The measurement of the inter-pen distance or spacing (S) involves two problems. The carriage 12 is moved at a constant velocity controlled by a servo via the linear encoder 22 and the code strip 23. The first problem in the measurement of inter-pen spacing (S) is that the very slow speed at which the drop detection must be performed (typically on the order of 0.625 to 0.833 inches per second) necessitates a special servo system configuration. The resolution of the linear encoder 22 is such that one encoder count will be traversed in two milliseconds. The high quality velocity feedback needed for stabilizing the servo loop can be obtained despite the quantization of the encoder feedback by timing between encoder counts.
The second problem is that the resolution of the measurement that is needed is greater than the 0.00125 inch quantization level of the linear encoder 22. This problem is solved by interpolating between encoder counts by means of time measurements. The time elapsed between encoder counts is available from the timing based servo previously described. An additional timer provides the time elapsed from the last encoder count until drop detection is indicated by the drop detector 24. The ratio of these times can be used to interpolate the position of the carriage12 at the time of the drop detection. Comparison of the positions of the carriage 12 for all pens 14-18 provides the inter-pen spacing (S). Actual test results have shown that position measurements of 0.0004 inch or better are obtained.
This measurement of the inter-pen spacings S is performed automatically to one side of the print zone P, and the result of the measurement is converted to a correction algorithm to electronically compensate the drop fire timing and image data. This enables the multi-pen thermal ink jet printer 10 of the present invention to accurately overlay the primary color dots, thus resulting in a high quality image being produced.
As is well known, the cartridges or pens 14-18 are replaceable and are held in place by a latch mechanism and by mechanical registration surfaces. The repeatability of registration of the pens 14-18 to the carriage 12 directly affects the print quality. The body of the print cartridges or pens 14-18 has some uncertainty in dimension. Discrepancies in alignment of the pens 14-18 may result in offsets (O) or displacements of nozzle arrays relative to each other in the print media index axis (X) as shown in FIG. 5.
X-axis measurements are made by successively positioning each one of the pens 14-18 adjacent a special pattern 31 of openings provided in the piezoelectric film 25 and firing ink drops through the nozzle array to locate the nozzle pattern. Multiple tests per pen may be taken in one carriage pass. This operation is repeated for each of the pens 14-18 in the carriage 12. The special pattern 31 of punched openings is shown in FIG. 6, where it may be seen that the openings are rectangular and of varying lengths and arranged side-by-side in a stair-step pattern.
Some of the drops impact the piezoelectric film 25 and are detected. Others pass through the special pattern 31 of openings and are not detected. This information is mapped into the known position of each nozzle 21 to create a detect/no detect pattern for each of the pens 14-18. The patterns are then compared to determine relative offsets from pen-to-pen. If two of the pens 14-18 are determined to be out of alignment by more than one-half a dot row, the image data is shifted up or down in the nozzle arrays to produce the optimum alignment. Note that by doing so, nozzles 21 at the ends of the arrays may have to be sacrificed. That is, they will not be usable.
The algorithm is a detect/no detect pattern generated from each of the pens 14-18 to determine relative pen-to-pen offsets O. This algorithm for the pen alignment in the print media index axis (X) is employed as a correction algorithm to electrronically compensate the drop fire timing and image data. This enables the multi-pen thermal ink jet printer 10 of the present invention to accurately overlay the primary color dots, thus resulting in a high quality image being produced.
Thus, there has been described inter-pen offset determination and compensation in multi-pen thermal ink jet pen printing systems. It will be seen that the printer of the present invention measures drop location data in the nominal plane of the print media rather than at the orifice plate. It will be seen that the printer of the present invention detects drop position both in X and Y axes, not in just one axis. Also, it will be seen that the printer of the present invention compensates for directionality errors because it measures drop position in the nominal plane of the print media.
It is to be understood that the above-described embodiment of the invention is merely illustrative of the many possible specific embodiments which represent applications of the principles of the present invention. Numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the scope of the invention. | 4y
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CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. application Ser. No. 13/347,276, filed Jan. 10, 2012, which is a continuation of U.S. application Ser. No. 12/949,482, filed Nov. 18, 2010, now U.S. Pat. No. 8,113,856, issued on Feb. 14, 2012, which is a continuation of U.S. application Ser. No. 12/749,961, filed Mar. 30, 2010, now U.S. Pat. No. 7,862,365, issued Jan. 4, 2011, which is a continuation of U.S. application Ser. No. 12/331,523, filed Dec. 10, 2008, now U.S. Pat. No. 7,722,378, issued May 25, 2010, which is a continuation of U.S. application Ser. No. 11/207,853, filed Aug. 18, 2005, which claims priority from U.S. Provisional Application Ser. No. 60/603,142, filed Aug. 19, 2004, the entire disclosure of which is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to a cover for a jack module, and more particularly, to a tool for removing the cover from the jack module.
BACKGROUND OF THE INVENTION
Dust covers, also known as block-out covers, are frequently inserted into jack modules to protect the module and prevent entry of undesirable objects. Some covers include multiple parts or special latch connectors that secure the cover to the modules. Other covers have relatively large open areas designed to receive a flat tool that would enable the end user to release the cover from the module so that it could be removed from the module. The covers with the larger open areas, however, may be accidentally removed from the module.
There are also covers that are inserted in the opening of a module and then locked by a rotating key. These covers may only be removed by inserting the key and rotating it to unlock or release the cover from the module. Thus, it is desirable to provide an improved cover and removal tool where the cover would not be accidentally removed from a module but would be easily removed from the module by a simple tool.
SUMMARY OF THE INVENTION
The present invention is directed to a cover for a jack module and a tool for removing the cover from the jack module. The cover has at least one locking arm disposed within the cover for securing the cover to the jack module. The cover also has at least one window designed to receive the removal tool. The tool has a body, a lever secured to the body and prongs extending from the body. The prongs have a cam surface that deflects the cover from locking engagement with the jack module when the tool is inserted in the window in the cover. The lever engages the cover when the tool is inserted into the cover thereby enabling the tool to remove the disengaged cover from the jack module.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a perspective view of a block-out cover installed in a jack module and a block-out removal tool of the present invention;
FIG. 2 illustrates a top front perspective view of the block-out cover illustrated in FIG. 1 ;
FIG. 3 illustrates a top rear perspective view of the block-out cover illustrated in FIG. 1 ;
FIG. 4 illustrates a bottom rear perspective view of the block-out cover illustrated in FIG. 1 ;
FIG. 5 illustrates a top perspective view of the removal tool illustrated in FIG. 1 ;
FIG. 6 illustrates a bottom perspective view of the removal tool illustrated in FIG. 1 ;
FIG. 7 illustrates a top plan view of the block-out cover installed in the jack module and the block-out removal tool illustrated in FIG. 1 ;
FIG. 8 illustrates a cross sectional view of the block-out cover and the removal tool taken along line 8 - 8 in FIG. 7 ;
FIG. 9 illustrates a perspective view of the removal tool partially inserted in the block-out cover installed in the jack module illustrated in FIG. 1 ;
FIG. 10 illustrates a cross sectional view of the removal tool partially inserted in the block-out cover installed in the jack module taken along line 10 - 10 in FIG. 9 ;
FIG. 11 illustrates a front cross sectional view of the block-out cover installed in the jack module taken along line 11 - 11 in FIG. 10 ;
FIG. 12 illustrates a perspective view of the removal tool inserted in the block-out cover installed in the jack module illustrated in FIG. 1 ;
FIG. 13 illustrates a cross sectional view of the removal tool inserted in the block-out cover installed in the jack module taken along line 13 - 13 in FIG. 12 ;
FIG. 14 illustrates the removal tool removing the block-out cover from the jack module illustrated in FIG. 1 ;
FIG. 15 illustrates a side view of the removal tool being disengaged from the block-out cover illustrated in FIG. 1 ;
FIG. 16 illustrates a side view of the removal tool disengaged from the block-out cover illustrated in FIG. 1 ;
FIG. 17 illustrates a perspective view of an alternative design of the block-out cover installed in a jack module and a block-out removal tool of the present invention;
FIG. 18 illustrates a top front perspective view of the block-out cover illustrated in FIG. 17 ;
FIG. 19 illustrates a top rear perspective view of the block-out cover illustrated in FIG. 17 ;
FIG. 20 illustrates a bottom rear perspective view of the block-out cover illustrated in FIG. 17 ;
FIG. 21 illustrates a rear cross sectional view of the block-out cover taken along line 21 - 21 in FIG. 20 ;
FIG. 22 illustrates a top perspective view of the removal tool illustrated in FIG. 17 ;
FIG. 23 illustrates a bottom perspective view of the removal tool illustrated in FIG. 17 ;
FIG. 24 illustrates a front cross sectional view of the removal tool taken along line 24 - 24 in FIG. 22 ;
FIG. 25 illustrates a top plan view of the removal tool partially inserted in the block-out cover installed in the jack module illustrated in FIG. 17 ;
FIG. 26 illustrates a cross sectional view of the removal tool partially inserted in the block-out cover installed in the jack module taken along line 26 - 26 in FIG. 25 ;
FIG. 27 illustrates a cross sectional view of the removal tool partially inserted in the block-out cover installed in the jack module taken along line 27 - 27 in FIG. 25 ;
FIG. 28 illustrates a cross sectional view of the removal tool fully inserted in the block-out cover installed in the jack module illustrated in FIG. 26 ;
FIG. 29 illustrates a cross sectional view of the removal tool fully inserted in the block-out cover installed in the jack module illustrated in FIG. 27 ;
FIG. 30 illustrates a top front perspective view of the block-out cover of FIG. 17 with side spring tabs;
FIG. 31 illustrates a side view of the block-out cover of FIG. 30 installed in a jack module; and
FIG. 32 illustrates a cross sectional view of the block-out cover installed in a jack module taken along line 32 - 32 in FIG. 31 .
DETAILED DESCRIPTION
FIG. 1 illustrates the removal tool 60 and the block-out cover 30 installed in a jack module 20 of the present invention. As described below, the removal tool is designed to remove the block-out cover from the jack module by simply inserting the tool into the cover until the tool is attached to the cover. Next, the tool and attached cover are simply pulled out of the module.
As shown in FIGS. 2-4 , the block-out cover 30 includes a front 32 , back 34 and sides 36 that define an open center section 38 therebetween. The front 32 of the block-out cover includes two access windows 40 , as shown in FIG. 2 . The access windows 40 receive the prongs 80 of the removal tool 60 . The access windows 40 have a rectangular shape. However, the access windows may be formed from various shapes as long as the prongs 80 of the removal tool 60 are able to enter and be disposed therein.
The front 32 of the block-out cover 30 also includes a connection member 42 that is positioned below the access windows 40 preferably at the center of the cover. The connection member 42 is integrally formed with the cover. The connection member 42 includes a top portion 44 extending from the cover, a downwardly facing hook 46 and sides 48 , as illustrated in FIG. 8 . The hook 46 extends downward from the top portion 44 and the sides 48 surround the hook 46 . As will be described below, the hook 46 engages a hook 74 extending from the release lever 70 of the removal tool 60 to secure the removal tool 60 to the block-out cover 30 .
FIGS. 2-4 also illustrate the block-out cover 30 with locking arms 50 disposed in the open center section 38 of the block-out cover 30 . The arms 50 are integrally formed with the block-out cover 30 such that the arms 50 extend from the back 34 of the cover 30 into the open center section 38 . The arms 50 comprise first portions 51 , second portions or upwardly extending members 52 and third portions or downwardly extending members 54 . As shown in FIG. 8 , a portion of back 34 and arms 50 may form a generally U-shaped profile. Back 34 may comprise bar member 35 connecting the opposing sides 36 of the cover 30 , with an open space beneath bar member 35 such that back 34 is open ended. Additionally, each downwardly extending member 54 has a flange 56 that extends outwardly towards the sides 36 of the cover 30 . The upwardly extending members 52 enable the cover 30 to be secured inside the jack module 20 , as illustrated in FIG. 8 . As will be described below, the flanges 56 of the downwardly extending members 54 are deflected to enable the removal tool 60 to disengage the upwardly extending members 52 of the arms 50 from the jack module 20 .
FIGS. 5 and 6 illustrate the removal tool 60 of the present invention. The removal tool 60 has a partial oblong shaped body 62 that is easy to handle. The removal tool 60 , however, may be formed from a variety of shapes, as desired. The body 62 of the removal tool 60 includes an opening 64 in the center of the body and a front edge 66 . A release lever 70 is positioned within the opening 64 at the center of the removal tool 60 . The release lever 70 is integrally formed with the removal tool. The release lever 70 includes a raised knob 72 located near the center of the lever and an upwardly facing hook 74 located at the free end of the lever. As will be described with respect to FIGS. 15 and 16 , when the end user pushes the raised knob 72 downwards the hook 74 at the free end of the lever also moves downwards.
The removal tool 60 also includes two prongs 80 that extend from the front edge 66 of the tool 60 . One of the prongs 80 is preferably positioned on either side of the release lever 70 . Each of the prongs 80 includes an inner side 82 , an outer side 84 and a front end 86 . The prongs 80 include a ramp shaped cam 90 located on the inner side 82 of each prong 80 . The ramp shaped cams 90 extend from the front end 86 of each prong 80 downward towards the front edge 66 of the tool 60 . The ramp shaped cams 90 are designed to engage the flanges 56 of the downwardly extending members 54 of the arms 50 when the tool 60 is inserted in the block-out cover 30 .
As shown in FIGS. 7 and 8 , when it is desirable to remove the block-out cover 30 from the jack module 20 , the removal tool 60 is positioned such that the prongs 80 are aligned with the access windows 40 in the front of the block-out cover 30 and the lever 70 of the removal tool 60 is aligned with the connection member 42 extending from the front of the block-out cover 30 .
FIGS. 9 and 10 illustrate the removal tool 60 being partially inserted in the block-out cover 30 . As the prongs 80 of the removal tool 60 enter the access windows 40 in the block-out cover 30 , the ramp shaped cams 90 engage the flanges 56 of the downwardly extending members 54 of the arms 50 . As shown in FIG. 11 , the upwardly extending members 52 of the arms 50 of the block-out cover 30 engage an upper shelf 22 in the jack module 20 to maintain the block-out cover 30 in the jack module 20 . However, as the ramp shaped cams 90 engage the flanges 56 of the downwardly extending members 54 , the upwardly extending members 52 of the arms 50 are deflected away from the upper shelf 22 of the jack module 20 .
FIGS. 12 and 13 illustrate the removal tool 60 fully inserted into the block-out cover 30 . As illustrated in FIG. 13 , the ramp shaped cams 90 have deflected the arms 50 downwardly and back towards the back 34 of the cover 30 . As a result, the upwardly extending members 52 of the arms 50 no longer engage the upper shelf 22 of the jack module 20 . Since the arms 50 have been disengaged from the jack module 20 , the block-out cover 30 may be removed from the jack module 20 .
FIGS. 12 and 13 also illustrate that once the tool 60 has been inserted in the cover 30 , the hook 74 at the free end of the lever 70 snaps into engagement with the hook 46 extending from the connection member 42 of the cover 30 . Thus, the removal tool 60 is secured to the block-out cover 30 . As illustrated in FIG. 14 , after the removal tool 60 has been inserted and secured to the block-out cover 30 , the removal tool 60 and connected block-out cover 30 may be easily removed from the jack module 20 .
FIGS. 15 and 16 illustrate the removal tool 60 being removed from the block-out cover 30 . As illustrated in FIG. 15 , the release knob 72 of the lever 70 is depressed thereby lowering the hook 74 at the end of the lever 70 . As a result, the hook 74 at the end of the lever 70 is no longer engaging the hook 46 extending from the connection member 42 of the cover 30 . As shown in FIG. 16 , once the hooks have been disengaged, the tool 60 may be pulled away from the block-out cover 30 . As the tool 60 is pulled from the block-out cover 30 , the arms 50 of the block-out cover 30 move forward and upward back to their initial position.
FIGS. 17-29 illustrate an alternative design of the block-out cover and removal tool of the present invention. As illustrated in FIGS. 18-21 , the block-out cover 130 includes a front 132 , a back 134 and sides 136 that define an open section 138 therebetween. The front 132 of the alternative block-out cover 130 is shaped so that the block-out cover fits inside any standard RJ-45 data jack, as illustrated in FIG. 17 .
The front 132 of the block-out cover 130 includes two access windows 140 , as shown in FIG. 18 . The access windows 140 include a straight top portion 141 and a curved bottom portion 143 . The shape of the access windows 140 restricts the insertion of the removal tool 160 so that the tool 160 may be inserted in the access windows 140 in only one specific orientation, as shown in FIGS. 17 and 25 - 29 .
The front 132 of the block-out cover 130 also includes a connection member 142 that is positioned between the access windows 140 in the center of the block-out cover 130 . The connection member 142 is integrally formed with the block-out cover 130 . The connection member 142 includes a top portion 144 extending outwardly from the cover, a downwardly facing hook 146 and sides 148 , as illustrated in FIG. 26 . The hook 146 engages a hook 174 on the release lever 170 of the removal tool 160 to secure the removal tool 160 to the block-out cover 130 .
The block-out cover 130 also includes a single piece locking arm 150 integrally formed with the block-out cover 130 . The arm 150 extends from the back 134 of the cover 130 into the open center section 138 of the cover 130 . The arm 150 includes first portion 151 , second portion or an upwardly extending member 152 and third portion or a downwardly extending member 154 . As shown in FIG. 26 , a portion of back 134 and arm 150 may form a generally U-shaped profile. Back 134 may comprise bar member 135 connecting the opposing sides 136 of the cover 130 , with an open space beneath bar member such that back 134 is open ended. Additionally, the upwardly extending member 152 of the arm 150 engages an upper shelf 122 in the jack module to secure the cover 130 to the jack module 120 (see FIGS. 26-27 ). The downwardly extending member 154 includes flanges 156 that extend outwardly from each side of the downwardly extending member 154 . As shown in FIG. 21 , the flanges 156 extend towards the sides 136 of the cover 130 . As discussed below, the removal tool deflects the flanges 156 extending from the downwardly extending member 154 enabling the upwardly extending member 152 to become disengaged from the upper shelf 122 of the jack module 120 .
As illustrated in FIGS. 22-24 , the removal tool 160 includes a body 162 with an opening 164 in the center of the removal tool 160 and an angled front edge 166 . The removal tool 160 also includes a release lever 170 positioned within the opening 164 and prongs 180 that extend outwardly from the front edge 166 of the removal tool 160 . The release lever 170 has a raised knob 172 located near the center of the lever 170 and an upwardly facing hook 174 located at the free end of the lever 170 . The prongs 180 include an inner side 182 , an outer side 184 and a front end 186 . The inner side 182 of each prong 180 includes a curved cam 190 that extends from the front end 186 of each prong 180 downwards towards the front edge 166 of the tool 160 . The curved cam 190 increases the vertical deflection of the arm 150 when the removal tool 160 is inserted in the block-out cover 130 .
As illustrated in FIGS. 25-29 , the prongs 180 of the removal tool 160 are aligned with the windows 140 in the block-out cover 130 . As the prongs 180 of the removal tool 160 are inserted in the windows 140 of the block-out cover 130 , the curved cam surface 190 of the prongs 180 engages the flanges 156 to deflect the arm 150 downward and back towards the back 134 of the block-out cover 130 . As the prongs 180 deflect the arm 150 , the upwardly extending member 152 of the arm 150 is disengaged from the upper shelf 122 in the jack module 120 .
Additionally, as the removal tool 160 is inserted in the block-out cover 130 , the hook 174 of the release lever 170 engages the hook 146 of the connection member 142 to secure the removal tool to the block-out cover. Once the arm 150 has been disengaged, the removal tool and the attached block-out cover 130 may be removed from the jack module 120 . To remove the tool from the block-out cover, the release knob 172 of the lever 170 is depressed to lower the hook 174 at the end of the lever thereby disengaging the hook 146 of the connection member 142 . Once the hooks are disengaged, the removal tool 160 maybe removed from the block-out cover 130 .
If desired, the block-out cover may include a spring tab 137 located at each side 136 of the cover (see FIGS. 30-32 ). The spring tabs 137 fill the gap between the block-out cover 130 and the jack module 120 when the block-out cover 130 is installed in the jack module 120 . Thus, the spring tabs 137 provide a tighter fit between the block-out cover 130 and the jack module 120 .
The removal tool and block-out cover of the present invention provide a safe and secure device for blocking jack modules. The block-out cover is designed so that it may only be removed with the two pronged removal tool of the present invention. As a result, the block-out tool would not accidentally or undesirably be removed by a screwdriver or other flat tool.
Furthermore, while the particular preferred embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the teaching of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as limitation. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective based on the prior art. | 4y
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to charge couplings for electric vehicles and more particularly to couplings for detachably coupling supply connectors to battery connectors installed in electric vehicles for charging thereof.
2. Statement of the Prior Art
Since charging of a battery is essential to an electric vehicle, a power source for charging should be readily connectable to a battery installed in the vehicle. Heretofore, a battery connector is provided in the electric vehicle while a supply connector is connected to the power source. The supply connector is detachably connected to the battery connector to charge the battery.
As charging an electric vehicle requires a relatively long time in comparison with supplying gasoline, an operator can not always stand ready for charging. Particularly, in the case that the charging is carried out at home, it is difficult to effect rapid charging at a high current. Consequently, charging may be carried out when a vehicle is parked at an owner's home overnight. In this case, the supply connector is fitted to the battery connector to commence charging and is maintained in the fitting position for a long time at a lower current.
However, such conventional supply connectors have not been provided with satisfactory locking mechanisms. For example, conventional supply connectors are easily detached from the battery connector during charging. Consequently, a person not aware of the state of charge of a vehicle may detach the supply connector when charging is incomplete. Even if a lock mechanism is provided on a supply connector, charging may be started with the lock not fully engaged, whereby the supply connector may be accidentally disconnected from the vehicle battery connector.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a charging coupling for an electric vehicle, which can prevent a supply connector from being carelessly detached from a vehicle battery connector and prevent commencement of charging with the coupling not fully engaged.
In achieving the above object, a coupling for detachably fitting a supply connector to a vehicle battery connector to charge an electric vehicle in accordance with the present invention may comprise a lock mechanism for maintaining and releasing a coupling of the supply connector to the vehicle battery connector; and means for controlling the lock mechanism to actuate it only when charging is commenced and to release it only when charging is stopped.
The controlling means may be provided with means for detecting a complete coupling of the supply connector to the vehicle connector. The controlling means can be arranged to actuate the lock mechanism only when the detecting means detect the complete coupling and commencement of charging and to release the lock mechanism only when charging is stopped.
The lock mechanism may include means for detecting an operating state of the lock mechanism and means for indicating an operating state of the lock mechanism.
The lock mechanism would be actuated by the lock control means when charging is commenced after the supply connector is fitted to the vehicle connector. Consequently, the supply connector may be maintained in the coupled position in the vehicle connector, thereby preventing the supply connector from being disconnected.
The lock mechanism would be actuated after charging commences and complete fitting of the supply connector to the vehicle is detected.
A user can easily detect an abnormal operation of the lock mechanism by way of an indicator.
According to one aspect of the present invention, the supply connector cannot be disconnected from the vehicle battery connector carelessly during charging. Further, charging would not be interrupted or slowed since the supply connector cannot be detached from the vehicle battery connector. According to another aspect of the present invention, the lock mechanism is actuated after the supply connector is completely coupled with the vehicle battery connector, thereby preventing the supply connector from being locked in position without an electrical coupling. In addition, the lock indicator can prevent charging under abnormal operation of the lock mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of an embodiment of a coupling for charging an electric vehicle in accordance with the present invention;
FIG. 2 is a longitudinal sectional view similar to FIG. 1, illustrating the coupling in a locked position;
FIG. 3 is a plan view of the embodiment of FIG. 1, illustrating a part broken away;
FIG. 4 is a circuit diagram of a lock control circuit of the coupling; and
FIG. 5A is a time chart of the lock control circuit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of a coupling for detachably coupling a supply connector 1 to a vehicle battery connector 2 to charge an electric vehicle in accordance with the present invention will be explained below by referring to the drawings. As shown in FIG. 1, the supply connector 1 has a rectangular handle grip 11 and a cylindrical connector body 12 attached to a distal end of the handle grip 11 and is generally formed into a gun type shape. A charge cable 13 extends from a lower end of the handle grip 11 and is connected to a charging device 100, for example. The connector body 12 includes a cylindrical inner casing 14, an insulator 15, and a pair of charge terminals 16 (only one of them is shown) extending through an insulator 15 near a front, open end. When the supply connector is fitted to the vehicle battery connector 2 (not shown), the charge terminals 16 are electrically connected to terminals in the vehicle connector 2.
Also, the insulator 15 is provided in its interior with, for example, two pairs of connection detecting terminals 17, 17. When the supply connector 1 is fitted to the vehicle connector 2, the connection detecting terminals are conducted by a shorting terminal 18 (see FIG. 4).
As shown in FIGS. 1 and 3, a cylindrical sleeve 19 is mounted on an outer periphery of the inner casing 14 of the connector body 12 so that the sleeve cannot slide axially on but can rotate peripherally on the casing 14. The sleeve 19 is shorter than the inner casing 14. The sleeve 19 has an enlarged end which engages with an outer periphery of a guide cylinder (not shown) of the vehicle connector 2 when the supply connector 1 is fitted to the vehicle.
The sleeve 19 is provided on its inner periphery with a boss 20 (FIG. 1) which projects inwardly and is adapted to engage with a spiral groove formed in the guide cylinder (not shown) of the vehicle connector 2.
When the distal end of the supply connector 1 abuts on the vehicle connector 2 and the sleeve 19 is turned, the boss 20 moves in the spiral groove, thereby axially displacing the supply connector 1 as well as the sleeve 19 toward the vehicle connector 2. When the sleeve 19 is fully turned to displace the boss 20 to an end of the spiral groove, the connector body 12 is completely fitted to the vehicle battery connector 2. The connector body 12 can be detached from the vehicle by turning the sleeve 19 in a reverse direction.
The supply connector 1 is provided in its interior and near the proximal end of the sleeve 19 with a lock mechanism 21. The lock mechanism 21, as shown in FIGS. 1 and 2, includes a solenoid 22 and a lock rod 23 to be driven by the solenoid 22. The lock rod 23 can move axially or in right and left directions as shown in the drawings. The proximal end of the lock rod 23 is coupled to an end of a connecting arm 25 rotatably supported on a base 24 of the handle grip 11. The other end of the connecting arm 25 is coupled to a plunger rod 26 of the solenoid 22. When the solenoid 22 is energized to draw the plunger rod 26 to the left in the drawings, the lock rod 23 is advanced to the right in the drawings through the connecting arm 25.
The sleeve 19 is provided in its rear end with a U-shaped notch 27 which-opens rearwardly. If the solenoid 22 is energized when the sleeve 19 is rotated so that the notch 27 faces the lock rod 23, the distal end of the lock rod 23 enters into the notch 27 to lock the sleeve 19. A tension spring 29 is connected to a rear end of the lock rod 23 and to a support plate 28 secured to the handle grip 11 to bias the lock rod 23 toward a direction in which the lock rod 23 is extracted from the notch 27 (to the left in the drawings).
The plunger rod 26 is provided on its middle portion with a douser 26a. A photointerruptor 30 which constitutes lock action detecting means together with the douser 26a is disposed within a displacing area of the douser in the handle grip 11. When the solenoid 22 is energized to draw the plunger rod 26 to a position in which the lock rod 23 locks the sleeve 19, the douser 26a enters into the photointerruptor 30 to exert a switching action.
On the other hand, the handle grip 11 is provided in its interior with coupling detecting means 31 shown in FIG. 3. As shown in FIG. 3, the coupling detecting means 31 include a detecting piece 32 projected from the rear end of the sleeve 19 and a photointerruptor 33 secured to the handle grip 11 within a rotary area of the detecting piece 32. The photointerruptor 33 serves to detect completion of the coupling, namely a complete coupling of the sleeve 19 relative to the vehicle connector 2. When the sleeve 19 is turned to the complete coupling position to couple the supply connector 1 to the vehicle connector, the distal end of the detecting piece 32 enters into the photointerruptor 33 to exert a switching action.
As shown in FIG. 4, a lock control circuit 35 is provided in the handle grip 11 as means for controlling the lock mechanism 21. A power source 36 for charging and a charge switch 37 in the circuit 35 are arranged in a charging device 100 (FIG. 1) to which the supply connector 1 is connected. A charge line 38 is introduced from the charge power source 36 through the charge switch 37 into the connector body 12.
A control power source line 39 is introduced from the charge power source 36 through a branched point from an input of the switch 37 into the connector body 12. The control power source line 39 is connected to one of the connection detecting terminals 17, 17 described above in the connector body 12. A pair of connection detecting terminals 17, 17 are shorted by the shorting terminal 18 in the vehicle connector 2, when the supply connector 1 is fitted to the vehicle connector 2. Upon fitting the supply connector 1 to the vehicle connector 2, the control power source line 39 is drawn into the connector body 12 through the other connection detecting terminal 17.
In the connector body 12, the control power source line 39 is connected through a protective resistor 40 to a light emitting diode 33a of the photointerruptor 33 for detecting the completion of the coupling. When the supply connector 1 is coupled to the vehicle connector 2, the light emitting diode 33a lights. A phototransistor 33b of the photointerruptor 33 is connected to an output transistor 41 which drives the solenoid 22. When light from the light emitting diode 33a is interrupted by the piece 32 (FIG. 3) to turn the phototransistor 33b to OFF, the output transistor 41 is turned to ON. When the transistor 41 is turned to ON, the solenoid 22 is conducted under a condition in which the charge switch 37 is turned to ON.
A lamp 42, which indicates completion of the coupling and is arranged on an upper face of the handle grip 11, and a protective resistor 43 are connected in series between a collector of the output transistor 41 and the control power source line 39. When the transistor 41 is turned to ON, the lamp 42 is lit.
The charge line 38 is connected to a light emitting diode 30a of the photointerruptor 30 for detecting a lock action and to a phototransistor 30b. An output transistor 44 is driven reversely by the phototransistor 30b. A lamp 45, which indicates completion of lock and is arranged on the upper face of the handle grip 11, and a protective resistor 46 are connected in series to a collector of the output transistor 44. The lamp 45 is lit when the transistor 44 is turned to ON. The collector of the output transistor 44 is connected to a signal terminal 47 of the connector body 12. A signal from the terminal 47 is conducted through a relay 48 installed in the vehicle to close relay contacts 48a.
Charging of a battery (50) in the electric vehicle by using this embodiment of the supply connector 1 is carried out by the following steps. First, an operator holds the handle grip 11 and contacts the distal end of the connector body 12 with the guide cylinder of the vehicle connector 2. Then, the operator turns the sleeve 19 in the clockwise direction while lightly pushing the entire supply connector 1 toward the vehicle connector 2. The boss 20 on the sleeve 19 enters into and moves in the spiral groove in the vehicle connector 2. Thus, the connector body 12 is drawn into the guide cylinder of the vehicle connector 2, thereby electrically interconnecting the female and male terminals.
When the connection detecting terminals 17, 17 are connected to the shorting terminal 18 in the vehicle connector 2, a voltage is applied to the control power source line 39 in the connector body 12, so that the light emitting diode 33a of the photointerruptor 33 for detecting the completion of the coupling is lit (time t1 in FIG. 5). When the sleeve 19 is turned to the complete coupling position so that the supply connector 1 is completely fitted to the vehicle connector 2, the phototransistor 33b of the photointerruptor 33 is turned to OFF and the output transistor 41 is turned to ON, thereby lighting the lamp 42 for indicating the completion of the coupling (time t2 in FIG. 5).
Then, charging is commenced, that is, the charge switch 37 is turned to ON (time t3 in FIG. 5). A voltage is applied to the charge line 38, so that the solenoid 22 is energized, the plunger rod 26 is drawn to insert the distal end of the lock rod 23 into the notch 27 in the distal end of the sleeve 19 and the sleeve 19 is locked to the connector body 12 not to be rotated. Since the sleeve 19 cannot be turned relative to the connector body 12 under this state, it is impossible to detach the supply connector 1 from the vehicle inlet.
Since the douser 26a of the plunger rod 26 enters into the photointerruptor 30 when the plunger rod 26 of the solenoid 22 is drawn to the lock position, the phototransistor 30b is turned to OFF, so that the lamp 45 is lit to indicate a proper lock state (time t4 in FIG. 5). When the phototransistor 30b of the photointerruptor 30 is turned to OFF and the output transistor 44 is turned to ON, the relay 48 in the vehicle connector 2 is energized, so that the relay contacts 48a are closed to supply power to a circuit 50 being charged in the vehicle inlet through the charge line 38, thereby commencing charging (time t5 in FIG. 5).
When charging is complete, the charge switch 37 of the charging device 100 is turned to OFF (time t6 in FIG. 5). Then, the relay 48 is deenergized to stop supplying of power to the circuit (battery) 50 being charged and to deenergized the solenoid 22. Consequently, in the lock mechanism 21, the lock rod 23 is moved to the left in FIG. 2 by the spring 29 to extract the distal end of the lock rod 23 from the notch 27, thereby allowing the sleeve to be rotated. Accordingly, if the operator turns the sleeve 19 in the anticlockwise direction, it is possible to detach the supply connector 1 from the vehicle connector 2.
In this embodiment, after the supply connector 1 is coupled to the vehicle connector 2, when the charge switch 7 is turned to ON, the solenoid 22 is energized to actuate the lock mechanism 21 and the supply connector 1 cannot be detached from the vehicle connector 2 unless the charge switch 37 is turned to OFF.
In particular, the lock mechanism 21 is actuated under a condition in which the supply connector 1 is completely coupled to the vehicle connector 2 (the phototransistor 33b of the photointerruptor 33 is turned to OFF), in addition to a condition in which the charging is started. Thus, even if the charging is started with incomplete coupling, the lock mechanism is not actuated, so that the operator can detect the lock of a complete coupling and remedy the situation.
In this embodiment, when the lock mechanism 21 is properly actuated to lock the sleeve 19, the lock indicating lamp 45 is lit. Thus, it is possible to easily monitor whether or not the lock mechanism 21 is properly actuated.
The present invention should not be limited to the embodiment described above and illustrated in the drawings. For example, the following alternations may be effective:
(1) The lock mechanism which serves to lock the supply connector to the vehicle connector may be a mechanism in which the connector body is clamped by a pair of lock pawls on its opposite sides to prevent extraction. In a coupling accomplished by rotating the entire supply connector to couple it with the vehicle connector, a pin may be inserted into a body of the supply connector to preclude rotation. Any means for precluding detachment of the connector will be applied to various kinds of connector fitting mechanisms.
(2) Means for detecting the complete coupling of the supply connector to the vehicle connector are not limited to the means for detecting the rotation of the sleeve 19 in the embodiment. For example, a detecting terminal provided on the connector body 12 contacts with a terminal provided on the vehicle connector upon completion of the coupling. Also, for example, in a construction wherein the supply connector is coupled with the vehicle connector by engaging pawls, it is possible to detect the complete coupling by detecting displacement of the engaging pawls. Any means for detecting the completed coupling may be applied to various kinds of coupling mechanisms.
(3) Although the lock indicating means are constituted by the lock indicating lamp 45 made of the LED in the above embodiment, a construction wherein a liquid crystal display indicates the state of the lock mechanism by means of characters or pictorial symbols may be employed. | 4y
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BACKGROUND OF THE INVENTION
The present invention relates to a dressing tool for grinding wheels.
It has been known that dressing is an operation of removing the dull or loaded surface of the grinding wheel.
More particularly, the present invention relates to a dressing tool for grinding wheels which have a diamond coat on a base body and in which diamonds are held in a metallic bond in the coat. Such dressing tools may be cylindrical or profiled or alternatively wheels or dressing slabs.
The dressing operation is normally a mechanical shaping of a rotary grinding wheel, wherein the dressing tool is held against or applied to the working surface of the grinding wheel and producing controlled abrasion on the grinding wheel in such a fashion that the working surface of the grinding wheel will run perfectly true when rotating. A defined profile can be produced on the working surface of the grinding wheel.
The dressing operation is also used to produce a defined effective peak-to-valley height. When a workpiece is ground, the grinding wheel frequently tends to produce a defined roughness on the surface thereof. The degree of this roughness depends on the manner in which the dressing step on the grinding wheel was carried out. The effective peak-to-valley height is affected, on the one hand, by the kinematic dressing conditions, for example the rate of feed of the dressing tool on the grinding wheel surface in the direction of the axis of the grinding wheel. On the other hand, the grain size of the diamonds and the density of the diamond grain arrangement in the dressing tool also have a marked influence on the effective peak-to-valley height of the grinding wheel.
A dressing tool which is of simple construction but is versatile in use usually contains diamonds positioned in a systematic or random arrangement in a plane plate or so-called diamond coat. The diamond coat is joined to a base body which allows fixing to the grinding machine or to a device provided for dressing. Such a design of a dressing tool is termed a dressing slab.
The diamond coat is applied with its edge tangentially to the grinding wheel. Controlled abrasion on the grinding wheel is effected by diamond grains which are located in the region of the edge and are outwardly exposed to the grinding wheel.
In known dressing slabs, diamond grains are arranged in the plate in defined spacings. The diamond grains can lie as a single layer in one plane. Typical diamond grain sizes are between 0.5 mm and 1 mm. In cases where smaller diamond grains are used, they can also be arranged in several layers on top of one another.
During the dressings process of the grinding wheel, the grinding grains of which normally consist of corundum or silicon carbide, wear which occurs on the diamond grains of the dressing tool is relatively small. However, diamond grains must be held firmly by the surrounding metallic bonding material, so that they can adequately withstand the abrasive action of the grinding wheel. The bonding metal in which diamond grains are embedded must therefore also have a fairly high wear resistance. Typical bonding metals are alloys based on tungsten carbide and/or tungsten. If less wear-resistant bonding materials are used, such as, for example, cobalt, nickel or bronze, relatively rapid wear occurs on these metals, so that diamond grains embedded in the bond can break out of the bond at an unduly early stage. In the case of a dressing tool showing unduly rapid wear, however, the problem arises in maintaining precise dimensions during the dressing process, since the dimensions of the dressing tool may already change during the dressing process at predetermined feed rates. Moreover, the economic result of dressing would be unsatisfactory, because the dressing tool would wear out too rapidly, and unduly frequent replacement with a new tool would be necessary.
Diamond grains in the dressing tool are also subject to high thermal stresses due to intense friction on the grinding wheel. Diamond grades of high thermal stability are therefore chosen for such dressing tools. The disadvantage of the use of metal bonding based on tungsten or tungsten carbide resides in that relatively high sintering temperatures in the range of 900° are necessary to produce this bond, so that diamond grains which are to be embedded in the bond suffer a greater or lesser amount of thermal damage on sintering. A process similar to the sintering of metal powder, and likewise conventional, is sintering in combination with impregnation with a liquid metal.
A production method in which the application of high temperatures is unnecessary comprises the use of a metal which can be electro-plated, such as, for example, cobalt, nickel, bronze or copper. However, these metals do not possess a very high abrasion resistance.
Recent studies have shown that the disadvantage of the lower abrasion resistance of these bonding materials which can be electro-plated is less serious if a dense arrangement of diamond grains in the diamond coat is provided. However, it was then found that the metal skeleton remaining between the diamond grains has relatively thin cross-sections and is therefore unable to hold the diamond grains in the best way. In fact, if diamond grains are merely enclosed by the metal in the metallic bonding, an adequately adhering joint between the enclosing metal and the diamond grains is not produced. This applies both to the abovementioned sintered metal bonds or impregnated metal bonds and to the metals which can be electro-plated.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved dressing tool for grinding wheels.
It is another object of the invention to provide a dressing tool for grinding wheels, with which the aforedescribed disadvantages of conventional dressing tools are avoided.
These and other objects of the invention are attained by a dressing tool for grinding wheels, comprising a base body and a diamond coat on said base body, said diamond coat including diamond grains held in a metallic bond, said diamond grains being artificially roughened so that a surface area of said grains is enlarged by a factor of at least two as compared to a natural surface of diamond grains, said diamond grains being arranged in said coat with such a density that the majority of said diamond grains are in direct contact with adjacent diamond grains.
The diamond grains may have pore-like indentations formed by etching with metal.
Such an artificially produced surface topography allows an intimate anchorage of the diamond grains, especially in a metal which can be electro-plated, since the metal is able to penetrate into the additional pores of the surface of the grains, which are preferably provided with undercuts. A preferable characteristic of the topography of the surface is that it has many, relatively narrow indentations, into which the metal can penetrate in a root-like fashion, so that a mechanical joint of higher adhesive strength is produced between the bonding metal and the diamond surface. This can be achieved especially by the method in which the diamond grains are provided with pore-like indentations by etching with a metal.
The combination, according to the invention, of a very dense diamond grain arrangement of diamond grains of enlarged surface area and a special surface topography in an electro-plated metal as the joining and enclosing medium produces a dressing tool of high performance capacity.
The metallic bond may be an electro-plated metal, such as nickel, cobalt or their alloys.
The diamond grains may be arranged in a single layer or a plurality of layers so that the diamond grains of one layer engage between the diamond grains of another layer and being in direct contact with grains lying alongside, below and above said one layer.
The diamond grains may be arranged in at least one layer which is provided with at least one wear protective layer in which diamond grains are held in an electro-plated metal which may be of 0.1 to 1 mm thick and may be of cobalt or nickel.
Said at least one layer may consist of roughened diamond grains of approximately the same size of 500 to 1,000 μm, and said protective layers may each have approximately the same thickness as that of said at least one layer which is located between said protective layers which are composed of diamond grains of a size of up to 100 μm.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a front view of a dressing slab in the working position on a grinding wheel;
FIG. 2 is a plan view of the dressing slab on an enlarged scale;
FIG. 3 is a side view of the dressing slab on an enlarged scale;
FIG. 4 shows a diamond grain magnified 100 times;
FIG. 5 shows a part detail of the surface of a diamond grain, magnified about 1,000 times;
FIG. 6 shows diamond grains in a multi-layer arrangement;
FIG. 7 shows a diamond layer with diamond grains of different grain size;
FIG. 8 is a side view of a dressing slab with a wear protection layer on the diamond layer;
FIG. 9 is a side view of a dressing slab with several wear protection layers; and
FIG. 10 is a partial perspective view of a dressing slab after a short time in use.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in detail, FIGS. 1 to 3 illustrate a dressing tool 1 for a grinding wheel 2. The dressing tool is designed in the preferred embodiment as a dressing slab. The tool 1 is provided with a holder 3 which carries a diamond plate 4. The diamond plate 4 is formed of diamond grains 5 of the same grain size. Diamond grains 5 are arranged in such a way that they are in direct contact with adjacent diamond grains 5. For holding the grains, an electro-plating bond 6 made of nickel or cobalt is provided.
Individual diamond grains 5, of which one is shown roughened, especially by etching with a metal under the application of heat. As shown in FIG. 4 the surfaces of the individual diamond grain in the shape of a cubic octahedron are provided with numerous pores 7 which have the shape of indentations with undercuts as clearly seen in FIG. 5. As a result, the surface area which is active for holding the diamond grain within the bond is enlarged by a factor of at least two as compared with the natural surface size and, upon electroplating, the metal is able to penetrate in a root-like fashion into the individual pores, so that holding or adhesion is substantially improved. It is thus possible to arrange individual diamond grains in a high concentration when electroplating bonding agents are used, and to enhance the performance capacity of the dressing tool. This applies not only to slab-like dressing tools, but also to dressing tools designed in the form of rolls or wheels.
The present invention is not limited to the arrangement of diamond grains in one layer. FIG. 6 shows a further embodiment, in which a multiplicity of diamonds can be arranged in a layerless structure wherein individual diamonds or diamond grains are in contact with diamond grains lying alongside, above as well as below.
The use of diamond grain sizes of different orders is possible in accordance with FIG. 7, where small diamonds are located in the gaps between the larger diamonds; this arrangement permits a further increase in the diamond content.
The diamonds utilized in the embodiments described are synthetic diamonds, which are particularly suitable for use in tools according to the invention. However, this does not exclude a use of natural diamonds.
As shown in FIGS. 8 and 9, one embodiment of the invention provides for the arrangement, on a diamond layer 4, of a wear protection layer 10 which preferably has the thickness of 0.1 to 1 mm and consists of diamonds which are bonded in an electroplating metal such as cobalt or nickel. The surfaces of these diamonds in the wear protection layer 10 are again preferably enlarged by etching.
The provision of protection layers of sintered materials is known from other fields of application. In those cases, the protection layers are produced by powder-metallurgical processes. This involves the disadvantage that, in order to obtain a uniform layer thickness in the outer protection region, the thickness of the protection layer cannot be below a relatively large value, since even thicknesses of 0.8 mm cause problems in powder metallurgy. A further disadvantage of conventional methods is that, in powder-metallurgical production, the diamond concentration has a strict upper limit for process engineering reasons, and a concentration of more than 60 or 2.6 carat/cubic centimeter has not hitherto been feasible in practice. These disadvantages of the powder-metallurgical methods can be avoided by using electroplating, for example the electroplating of metals such as cobalt and nickel. Such electroplating allows a precise limitation of the thickness of the lateral protection layer so that, for example, layer thicknesses of the range of 0.2 to 1 mm can be used. It is then possible, especially for lateral protection to increase the diamond concentration substantially, namely to a concentration of 150 to 200, which is equivalent to 6.6 to 8.8 carat/cubic centimeter. Synthetic diamonds and also natural diamond grains can be used for this, whereby a substantial improvement in the holding of the diamond grains within the electroplated layer is generally obtained when the diamonds show an enlargement of their surface to preferably at least twice its natural size, obtained especially by etching, which would not lead to significant advantages in the case of a bond produced only by powder-metallurgical means. A special advantage here resides in that particularly small grain sizes can be used, which are only about half conventional grain sizes. This ensures extremely firm seating of the superficially pretreated diamonds in an electro-plating bond, so that the utilization level of the expensive diamond material is improved.
If the wear protective layer 10 is provided on the front and back sides of the diamond layer and additionally also on two other sides, the diamond layer 5, 6 is protected against movements in all directions.
In FIGS. 9 and 10, a dressing slab is illustrated which has diamond grains 5 arranged in one layer. These diamond grains are artificially roughened and bonded in a metal 6 by electro-plating. To protect diamond grains 5, two protective layers 10 and 12 are provided, the thickness of which approximately corresponds to the thickness of the diamond layer 4, 5. The grain size of the diamond grains 5 is about 750 μm. Therefore the protective layers 10 and 12 are also of a corresponding thickness. The protective layers however consist of diamond grains of substantially smaller size, in particular of grains or the order of 70 μm, size, for example.
The additional protective layers 10 and 12 prevent lateral "washing-out" of the bond of the effective diamond grains 5. This results in the advantage that individual diamond grains 5 of the dressing tool can be utilized to a higher degree, because they are firmly retained by the protective layers of the both sides of the diamond layer for a longer period. This is true in particular after a partial consumption of the protective layers according to FIG. 10, that is to say a state in which individual diamonds 5 protrude outwards i the feed direction, corresponding to the arrow, but are protected from lateral breaking-out by the protective layers 10 and 12.
The result of the provision of protective layers 10 and 12 is thus an improvement in the holding of the diamond grains arranged in the middle. The holding is anyway improved over comparable known arrangements by the artificial roughening of their surfaces and their bonding by electro-plating in an arrangement, in which they are in direct mutual contact.
The thickness of the diamond coat effects the precision of a dressing operation. For this reason, dressing slabs with a diamond coat thickness of not more than about 1 mm are particularly suitable. A diamond grain size of for example D 711 is suitable for this purpose.
In the case of multi-layer diamond surfaces, smaller diamond grain sizes, for example D 501, D 301 or D 181, can be used, maintaining the densest grain arrangement possible, in which a large proportion of adjacent diamond grains are in mutual contact.
In further modification of the dressing tools according to the invention, diamond grain mixtures of different grain sizes are used, for example D 711 with D 501 or with D 181 or with D 46 or mixtures of several of these grain sizes, for increasing the density of the diamond grain arrangement.
Three examples A, B and C of different types of dressing slabs are presented below.
Of the three examples, design A corresponds to the known structure, example B shows the results obtained with a slab which has a high diamond proportion of 0.8 carat, but without an artificially enlarged surface as in example C which has the same diamond proportion as design B, but with the surface enlarged according to the invention.
In all cases, the dressing tools are slabs with a coat area of 10 mm×15 mm and a working edge length of 10 mm, and with a diamond coat of a layer of diamons grains.
The results were obtained when dressing corundum grinding wheels of a diameter D=500 mm and a width b of 33 mm, the dressing being taken to a diameter of 300 mm. The dressing experiments were continued until 10 mm of the 15 mm deep grinding coat of the dressing slabs had been worn off. The table which follows shows the volumes removed by the dressing from the grinding wheels.
______________________________________Designs ofDressing Slabs A B C______________________________________Diamond grain size D 711 D 711 D 711Diamond grade Original Original Special topograph as a result of enlarged surfaceDiamond content 0.45 ct 0.8 ct 0.8 ctMetal bonding in Sintered Electro- Electro-the diamond coat metal plated plated Ni bond Ni bondGrinding wheel 6.5 dm.sup.3 14.0 dm.sup.3 21.1 dm.sup.3volume removedSpecific removal 14 dm.sup.3 /ct 17.5 dm.sup.3 /ct 264. dm.sup.3 /ctfrom the grindingwheels, referredto 1 ct of diamond______________________________________
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of dressing tools for grinding wheels differing from the types described above.
While the invention has been illustrated and described as embodied in a dressing tool for grinding wheels, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | 4y
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BACKGROUND OF THE INVENTION
A. Field of the Invention
The present invention relates to sensors which produce an optical signal to indicate the presence and/or concentration of a specified substance.
B. Description of the Prior Art
Optical sensors have been used to detect and quantify the presence of a substance of interest in a test medium through fluorescence quenching. By this approach, a source of light is used to stimulate fluorescence of a flourophore compound. The presence and/or concentration level of the substance of interest can then be detected due to the quenching effect that the substance has on the intensity of the fluorescence.
Fluorescence quenching has been used, particularly, to detect and quantify oxygen (O 2 ) concentration. For such sensors, a ruthenium based compound or "ruthenium complex" has been used as the flourophore to provide the requisite fluorescence. The use of ruthenium complexes in oxygen sensors have been described in the following publications: Hartman, Leiner and Lippitsch, Luminescence Quenching Behavior of an Oxygen Sensor Based on a Ru(II) Complex Dissolved in Polystyrene, 67 ANAL. CHEM. 88 (1995); Carraway, Demas, DeGraff, and Bacon, Photophysics and Photochemistry of Oxygen Sensors Based on Luminescent Transition-Metal Complexes, 63 ANAL. CHEM. 337 (1991); and Bacon and Demas, Determination of Oxygen Concentrations by Luminescence Quenching of a Polymer-Immobilized Transition-Metal Complex, 59 ANAL. CHEM. 2780 (1987).
In addition to ruthenium complexes, other flourophores have also been used to detect oxygen, as described in the following publications: Wolfbeis, Posch and Kroneis, Fiber Optical Fluorosensor for Determination of Halothan and/or Oxygen, 57 ANAL. CHEM. 2556 (1985); and Wolfbeis, Offenbacher, Kroneis and Marsoner, A Fast Responding Fluorescence Sensor for Oxygen, I MIKROCHIMICA ACTA WIEN! 153 (1984). U.S. Pat. Nos. 5,176,882 to Gray et al., 5,155,046 to Hui et al., and 4,861,727 to Hauenstein et al. also disclose various flourophores which may be used to detect oxygen. As shown in several of the above cited references, substances besides oxygen can also be detected through the use of a fluorescence quenching mechanism.
More generally, luminophores have been used to facilitate optical sensing. As used herein, a "luminophore" is a chemical species which reacts to the presence of a substance to produce an optical result. A flourophore is thus one type of luminophore. Another type of luminophore changes color in accordance with changes in the amount of a substance of interest. A sensor which utilizes this principle to detect pH and Co 2 is disclosed in Weigl, Holobar, Trettnak, Klimant, Kraus, O'Leary, and Wolfbeis, Optical Triple Sensor for Measuring pH, Oxygen and Carbon Dioxide, 32 JOURNAL OF BIOTECHNOLOGY 127 (1994).
Luminophore-based sensors typically use a LED or lamp as a light source, requiring an external power supply which can add noise and variability to sensor operation due to variations in the supply power. Where the power supply has a limited life, such as when batteries are used as the power source, the operation of the sensor is limited by the operational lifetime of the power supply. The need to provide a power supply can thus be a limiting factor for many remote sensing applications, such as for chemical sensing during space missions where power is scarce and long term stability is required.
SUMMARY OF THE INVENTION
As described herein, there is provided an optical sensor which is self-powered, and which is therefore particularly suited for many applications where the requirement for powering the sensing mechanism may be a limiting factor. In the following described preferred embodiment, an oxygen sensor is disclosed which is energized by a radioluminescent light source to detect a selected substance in a test medium. The sensor includes a luminophore matrix exposed to the test medium which absorbs light from the radioluminescent source. The sensing matrix produces an optical characteristic in response to the absorption of light from the radioluminescent source which varies with the presence of the selected substance. A photodetector detects the optical characteristic and provides a corresponding signal to indicate detection of the selected substance in the test medium.
By one aspect of the present invention, an optical sensor is provided with a continuous and reliable source of light from the energy released by the decay of a radioactive isotope in a radioluminescent material. The sensor is particularly useful in remote sensing systems, such as in deep sea or outer space applications. Also, such a sensor generally provides a more efficient and reliable optical sensing system for any application.
By another aspect of the present invention, an optical sensor is provided with a self-powered light source by the use of a radioluminescent material which includes a radioactive beta emitter constituent and a phosphor constituent energized by beta particles from the radioactive constituent to emit light. By appropriate selection of the phosphor compound, the wavelength of light produced by the radioluminescent source may be matched to a corresponding sensing matrix to optimally configure the sensor for the detection of a particular substance of interest.
As taught herein, an optical sensor is constructed which includes a sensing matrix that absorbs light from a radioluminascent source to produce an optical characteristic. The optical characteristic is detected by a photodedector which provides a corresponding signal. The optical characteristic and corresponding photodetector signal changes upon exposure of the sensing matrix to a selected substance. As used herein, "selected substance" means any type of chemical species, including, for example, O 2 , CO 2 , or pH level; and "optical characteristic" means any detectable property of the sensing matrix resulting from the absorption, reflection, or emission of electromagnetic radiation. Examples of optical characteristics include, but are not limited to, color, intensity of reflected or emitted light, and absorption or emission spectra.
Accordingly, one object of the present invention is to provide an optical sensor which has a self-powered light source.
Another object is to provide an optical sensing system with a self-powered light source having improved power efficiency, reliability, and long term operability.
Still another object of present invention is to provide an RL light source for a luminophore-based optical sensor which is optimally configured to detect a particular substance of interest.
Further objects, features, and advantages of the present invention shall become apparent from the detailed drawings and descriptions provided herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of one preferred embodiment of an optical sensing system of the present invention;
FIG. 2 is a schematic illustration of one preferred embodiment of a probe sensor of the present invention;
FIG. 3 is an intensity-time profile for one preferred embodiment of an oxygen sensor of the present invention;
FIG. 4 is a calibration curve for the oxygen sensor profiled in FIG. 3; and
FIG. 5 is a calibration curve for the oxygen sensor profiled in FIG. 3 with improved linearity.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, any alterations and further modifications in the illustrated device, and any further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
FIG. 1 schematically illustrates an optical sensor system 1 of the present invention. System 1 includes signal processing subsystem 10 coupled to sensor 20 by coupling 25. Sensor 20 is depicted in a schematic sectional view and includes a radioluminescent light (RL) source 30, test cell 40, sensing matrix 50, and photodetector 60. RL source 30 is enclosed or housed in container 32 along with plug 36. Container 32 has top portion 31 opposing transmission portion 33. Top portion 31 defines a closable opening (not shown) to facilitate placement of RL source 30 and plug 36 within container 32. Lid 35 provides for closure of container 32. Preferably, container 32 is manufactured from a transparent glass.
RL source 30 includes a radioactive isotope which supplies energy to produce light from radioactive decay. In one preferred embodiment, RL source 30 comprises a radioactive constituent which emits beta particles and a phosphor constituent which emits light in response to bombardment by beta particles from the radioactive constituent. The wavelength and intensity of light generated by this embodiment may be established by those skilled in the art by adjusting the type, amount, and relative orientation of the radioactive isotope and phophor constituents.
Light emitted by RL source 30 is symbolically represented by arrows 38. Plug 36 is configured to contain the beta radiation and provide mechanical strength to RL source 30. Plug 36 may be a conventional epoxy compound. Transmission portion 33 of container 32 is configured so that light from RL source 30 transmits therethrough. Optical filter 34 provides for the selective transmission of light from RL source 30 to test cell 40. As used herein, "optical filter" means any device which may be used to transmit a selected wavelength or selected range of wavelengths of electromagnetic radiation.
Test cell 40 includes opposing walls 42, 44 which define space 45 configured to receive a test medium. A test medium enters test cell 40 along a pathway indicated by arrow 46 and exits the pathway along arrow 48. Test cell wall 42 is configured to permit the transmission of light from optical filter 34 therethrough. Light also passes through space 45 containing the test medium before encountering sensing matrix 50. For this configuration, the test medium is a gas or liquid which permits the transmission of light therethrough. In other embodiments, the test cell may be configured to define a space configured to receive a test medium without walls or a particular pathway. For example, filter 34 and sensing matrix 50 may be positioned to define an appropriate test cell therebetween.
Sensing matrix 50 has sensing surface 52 adjacent space 45. Sensing matrix 50 is stimulated by the absorption of light transmitted from RL source 30. Preferably, sensing matrix 50 is permeable to facilitate detection of a desired substance in a test medium contained within test cell 40 via sensing surface 52. In one preferred embodiment, sensing matrix 50 is configured to immobilize a luminophore compound within a membrane or film which is permeable to the substance of interest. This configuration reduces abrasion and leaching of the luminophore compared to direct exposure on sensing surface 52 exposed to the test medium. However, in other embodiments, the sensing matrix may include a luminophore on a surface and the sensing matrix configuration may be other than a membrane or film.
Sensing matrix 50 produces an optical characteristic which varies with the presence of a selected substance in test cell 50. This varying optical characteristic is represented by arrows 58 and is detected by photodetector 60 through optical filter 64. For one embodiment, this optical characteristic is the intensity of light detected by photodetector 60 as a function of sensing matrix color. For another embodiment, this optical characteristic includes fluorescence intensity of the sensing matrix.
Photodetector 60 provides a signal corresponding to the optical characteristic which is input to signal processing subsystem 10 via coupling 25. Subsystem 10 is schematically depicted and processes the input sensor signal to provide sensing information using conventional techniques. Subsystem 10 includes signal conditioning portion 12 which may provide signal filtering, amplication, linearization, and other conventional signal conditioning. Subsystem 10 also includes display 14 to provide sensing information to an operator. A recording device 16 is also shown which may be used to record sensing information derived from the photodetector signal. This record may include the photodetector signal relative to another parameter such as time or test medium flow rate through test cell 40.
Photodetector 60 may be a photomultiplier tube or photodiode of a conventional type electrically connected to subsystem 10 by coupling 25. Coupling 25 schematically corresponds to the type of photodetector 10 selected and typically will include multiple electrical interconnections. Subsystem 10 may be configured for electronic, electrical, mechanical, and electromechanical devices of a conventional type which are interconnected to meet sensor detection and analysis requirements. Preferably, subsystem 10 is a programmable microprocessor-based system and signal conditioning portion 12 includes appropriate analog to digital conversion circuitry. In one embodiment, subsystem 10 includes a calibration means (not shown). Preferably, subsystem 10 may be adapted for use with multiple sensors.
One configuration of the preferred embodiment of sensing system 1 is next discussed which is particularly designed to detect oxygen. For this configuration, RL source 30 of sensor 20 includes 147 Pm as the radioactive constituent and ZnS:Ag as the phosphor constituent. Beta particles from the radioactive decay of the 147 Pm isotope energize the ZnS:Ag phosphor to produce blue light. This light is transmitted through transmission portion 33, optical filter 34, wall 42, and space 45 to sensing matrix 50.
Sensing matrix 50 has a flourophore portion that emits fluorescent light in response to the absorption of blue light from RL source 30. This flourophore is the ruthenium complex tris(4,7-diphenyl-1, 10-phenanthroline) ruthenium (II) chloride (Ru(dpp) 3 ). Preferably, sensing matrix 50 for this embodiment further includes an oxygen permeable Polyvinyl Chloride (PVC) membrane in which the ruthenium complex is immobilized. Flourescence from the flourophore portion is quenched by O 2 . When a test medium with O 2 passes through test cell 40 along arrows 46, 48, the intensity of the fluorescence emitted by sensing matrix 50 decreases with increasing O 2 concentration. The intensity of the fluorescence emission provides an optical characteristic indicative of O 2 concentration which is detected by photodetector 60. Photodetector 60 inputs a corresponding signal to subsystem 10. Subsystem 10 conditions the signal and provides a display and record of information corresponding to the signal. For this configuration, optical filters 34 and 64 are used to improve linearity of the sensor by reducing stray radiation. Filter 34 selectively passes light to excite the fluorophor while filter 64 passes only the light emitted from the excited fluophore.
FIG. 2 shows sensor 120 of the present invention depicted in a partial schematic sectional view. Sensor 120 includes RL source 130 housed within probe 132. Probe 132 has generally cylindrical probe body 136 with tip 131 opposing base 133. Preferably probe body 136 is formed from transparent glass. RL source 130 is optically coupled to probe body 136 via optical filter 134. Mirror 135 is positioned at tip 131 of probe 132 to reflect light from RL source 130 into probe body 136.
RL source 130 emits light into probe body 136 as represented by arrows 138. At least a portion of this light is absorbed by sensing matrix 150 configured as a cylindrical membrane coupled to outer surface 139 of probe 132. Sensing surface 152 of sensing matrix 150 is at least partially covered by coating 154 to block ambient light. Other embodiments may not include coating 154. In one embodiment, coating 154 is an opaque silicone compound.
Probe 132 is configured for exposure to a test medium including the substance or substances to be detected by sensor 120. Notably, the test medium need not transmit light to sensing matrix 150. Sensing matrix 150 responds to the presence of the selected substance to provide a detectable optical characteristic. Arrows 158 represent this optical characteristic. This optical characteristic is detected by photodetector 160. Optical filter 164 and optical fiber 166 are coupled to sensing matrix 150 and photodetector 160 to transmit the optical characteristic from probe 132 to photodetector 160. Photodetector 160 provides a signal corresponding to the optical characteristic. A signal processing subsystem (not shown) similar to subsystem 10 shown in FIG. 1 may be used to process a signal from photodetector 160 via appropriate electrical coupling.
Sensor 120 may be configured to detect oxygen using an RL source 130 that includes 147 Pm and phosphor ZnS:Ag to generate blue light. This light may be used to excite a ruthenium complex flourophore contained in sensing matrix 150. Fluorescent intensity indicative of oxygen quenching may be detected by photodetector 160 via optical filter 164 and optical fiber 166. Optical fiber 166 is depicted with a break to schematically represent the relative greater length of optical fiber 166 compound to probe 132 in typical applications.
Sensing matrix 150 and coating 154 are configured to permit the passage of the substance being detected to the flourophore portion of the sensor. Coating 154 is preferably opaque to reduce the amount of ambient light reaching the sensing matrix through the test medium and thereby improve noise immunity of system 101. Optical filters 134 and 164 are used to improve sensor 120 linearity and reduce optical noise from background radiation.
Referring generally to FIGS. 1 & 2, photodetector 60, 160 may be a photomultiplier tube, photodiode, or other type of photodetection device as would occur to those skilled in the art. In other embodiments, fewer or more optical filters 34, 64, 134, 164 could be used as would occur to those skilled in the art. Generally, the optical filter is matched to the detected optical characteristic of the sensing matrix 50, 150 and light spectrum emitted by RL source 30, 130. The solid diagonal lines used to portray items 30, 36, 50, 60, 130, 150, and 154 are not intended to indicate a specific type of material, but rather generally depict a cross-sectional view.
Besides a sensing matrix with Ru(dpp) 3 in PVC, tris(1, 10-phenanthroline) ruthenium (II) chloride (Ru(phen) 3 ) immobilized in a silicone substance also provides a sensing matrix suitable to detect oxygen when energized by an RL source. Other ruthenium complexes may also be used. For example, ruthenium complex matrices including, but not limited to: (1)Ru(dpp) 3 in polystyrene, Ru(dpp) 3 in sol-gel, and ruthenium-tris (dipyridyl)-dichloride in silicone may be used as suitable fluorophores. In addition, polycyclic aromatic hydrocarbons (PAHs) in a glass support and PAHs in a polymer may be used in a fluorescence quenching type oxygen sensor powered by an RL source. The previously cited publications mention other compounds as well which could also be used as a fluorophore to be stimulated by light from an RL source in an optical sensor. Generally, these flourophores may be used in accordance with the present invention with conventional modifications to optical filters and phosphors as are known to those skilled in the art.
It is to be appreciated that in accordance with the present invention, a variety of biosensors can be constructed to monitor biochemical reactions. Such a biosensor may be made, for example, by coupling an oxygen sensor of the present invention to an appropriate oxydase enzyme or yeast. Such biosensors could be used to sense a wide variety of biological substances and reactions, including cholesterol, glutamate, glucose, lactate, and biological oxygen demand. Biosensing techniques which could incorporate a sensing mechanism of the present invention are described in the following publications: Baker and Gough, A Continuous, Implantable Lactate Sensor, 67 ANAL. CHEM. 1536-52 (1995); Li and Walt, 67 ANAL. CHEM. 3746-52 (1995); Preininger, Klimant and Wolfbeis, Optical Fiber Sensor for Biological Oxygen Demand, 66 ANAL. CHEM. 1841-46 (1994); and Moreno-Bondi, Wolfbeis, Leiner and Schaffar, Oxygen Optrode for Use in a Fiber-Optic Glucose Biosensor, 62 ANAL. CHEM. 2377-80 (1990).
Also, it is to be appreciated that optical sensors of the present invention can be constructed to detect a variety of substances in addition to oxygen. For one embodiment, an optical sensor useful to detect CO 2 may be energized by light from an RL source. The sensing matrix for this sensor includes a luminophore portion which displays a change in color based on the concentration of CO 2 . As a result, a variable absorption of light form the RL source provides a variable light intensity level suitable for detection by a photodetector. Similarly, a sensor to detect solution pH may be constructed using a properly selected RL source and sensing matrix configured with a luminophore portion. Table 1 provides a listing of examples of matching constituents of RL light sources, luminophores, and preferred matrix fillers for O 2 , CO 2 , and pH sensing mechanisms.
TABLE 1______________________________________Sensor RL source Luminophore Filler______________________________________O.sub.2 ZnS:Ag and ruthenium silicon/PVC/ .sup.147 Pm complexes polystyreneCO.sub.2 Y.sub.3 (Al, Ga).sub.5 m-cresol ethyl cellulose O.sub.12 :Ce purple and .sup.147 PmpH Y.sub.2 O.sub.2 S:Eu Merck N9 cellulose and .sup.147 Pm triacetate______________________________________
Besides 147 Pm, other radioactive isotopes may be selected which are suitable for the RL source including 3 H and 14 C. In addition, the previously cited publications provide further examples of luminophore-based optical sensors which may be adapted for use with a self-powered light source in accordance with the present invention.
EXPERIMENTAL SECTION
The following examples are provided to further describe the objects, features, and advantages of the present invention, the same is to be considered as illustrative and not restrictive or limiting in character.
Example 1
In one experiment, a self-powered optical sensor was constructed in accordance with the present invention using an RL source. The RL source included 20 uCi of 14 C as the radioactive isotope in a 14 C-hexadecane radioactive constituent. The phosphor constituent of the RL source included 0.05 gram of ZnS:Ag. The RL source provided a source of blue light. The luminophore was a ruthenium complex of tris(1,10-phenanthroline) ruthenium (II) chloride (Ru(phen) 3 ). The Ru(phen) 3 flourophore was immobilized in a silicone compound in the form of a membrane to provide the sensing matrix.
The sensor was constructed by enclosing the RL source in the bottom of a glass vial and fixing an epoxy plug over it. A plastic lid was used to seal the top of the vial. The sensing membrane was attached to the bottom of the glass vial adjacent a space configured for a flow through sample. The sensing membrane and container were spaced apart from the surface of a photomultiplier tube to define the sample space. Distinct signal changes were observed when the sample space was alternatively filled with pure nitrogen and oxygen.
Example 2
In another experiment, the RL source was constructed in the following manner. In a 3.4×0.7 cm outer diameter glass vial, 15.2 milligrams of the phosphor constituent ZnS:Ag was completely mixed with 110.3 microliters of 1 molar NaOH, then 94.3 microliters of 147 PMCl 3 solution (activity=0.5 mCi) was added to serve as the radioactive constituent. After the vial was air-dried in a fume hood for 4 days, the dry residue was covered by 0.8 milliliters of epoxy (epo-tek 301, Epoxy Technology Inc.) and oven-cured for 1 hour at 65° C. The vial was then covered with a plastic lid, sealed with a thick layer of epoxy, and oven-cured for 1 hour at 65° C. The glow from the radioactive ZNS:Ag layer was visible to the eye in darkness. Tris(4,7-diphenyl-1,10-phenanthroline) ruthenium (II) chloride (Ru(dpp) 3 ) was immobilized in a layer of PVC. The resulting membrane was dip-coated on the outer surface of the vial to provide a sensing matrix. The components of the polymer solution for preparing the PVC membrane were 10 milliliters tetrahydrofuran (THF), 1.5 milliliters methanol, 1 gram PVC, 40.5 milligrams Ru(dpp) 3 and 5 milliliters 2-nitrophenyl octyl ether.
FIG. 3 shows the response of the oxygen sensor to alternating nitrogen and oxygen exposure using the detection optics of a SLM AMINCO SPF-500C spectrofluorometer to monitor the Ru(dpp) 3 fluorescence. A calibration curve for this novel oxygen sensor is shown as a conventional Stern-Volmer plot in FIG. 4. Important sensor characteristics are:
1. Detection limit: 3.4 torr (0.45%) O 2 ;
2. Dynamic range: 3.4˜760 torr; and
3. 95% response time: 12.5 ± 0.6 seconds.
The downward curvature of the calibration curve in FIG. 4 was improved by placing a blue optical filter between the RL source and the sensing matrix. FIG. 5 depicts the improved calibration curve as a comparison with FIG. 4 demonstrates.
All publications, patents, and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | 4y
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BACKGROUND AND BRIEF SUMMARY OF THE INVENTION
The invention relates generally to robotics and is concerned in particular with an improved apparatus for manipulating workpieces and the like.
There are a wide variety of manufacturing operations which involve the handling and processing of individual workpieces. The workpiece may be carried sequentially through a plurality of workstations where various tasks may be performed such as stamping, deburring, dipping, etc.
If the workpiece is completely released at a workstation, after being retrieved the workpiece usually must be reoriented to a known attitude and position before further processing can take place, this takes time. In such manufacturing operations, it is desirable to maintain hold of the workpiece as it is processed, both to control the location of the workpiece as it is introduced into a workstation and to save the time needed to regrasp the finished piece.
The known automated workpiece handling systems are generally used where there is no need to control the location of the workpiece by the manipulator or where the finished piece need not be regrasped after processing. One of the reasons for this is that the manipulators in these systems are rigid and massive. They are not designed to be compliant and to accomodate the shock force that may be produced at a workstation for example by a press. Further, they cannot release and regrasp the workpiece with sufficient speed to be particularly advantageous. There are manufacturing operations where it would be desirable both to rigidly grasp the workpiece and move it to a workstation, and at the workstation, to relax the grip on the workpiece such that during a stamping operation or the like, the workpiece could move while the gripper maintained its grasp on the workpiece.
Our invention accomplishes the foregoing by providing a linkage device which is advantageously secured at one end to a robot arm and secured at the other end to a gripper, which gripper holds a workpiece. The linkage device, upon command, provides for relative angular movement between its ends and therefore between the workpiece and the robot arm. When the workpiece is subjected to shock the linkage absorbs the shock.
Our invention in a preferred embodiment provides a linkage device having a first link secured to a first object, such as a robot arm, and a second link secured to a second object, such as a gripper which holds a workpiece. The first and second links are disposed in a housing and adapted for relative angular motion one to the other. The device further includes locking pistons to rigidly secure the links within the housing; and alignment rings to reorient the links. The device functions in at least one of three modes; a locking mode to provide a rigid linkage between the objects; an air bearing mode which provides a flexible linkage between the objects; and an alignment mode to provide a standard resettable linkage between the objects.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of a linkage device embodying the invention joined at one end to a workpiece gripper and at the other end to a robot arm;
FIG. 2 is a side schematic view of the linkage device;
FIG. 3 is a fragmentary sectional view of the linkage device; and
FIG. 4 is a top view of the linkage device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment will be described in reference to the linkage device functioning as a wrist and having secured to one end a workpiece gripper and being secured at the other end to a robot arm.
Referring to FIG. 1, a wrist 10 at one end is connected to a three-fingered gripper 12 which is a standard device. A pneumatic line 14, communicates with the gripper 12. The wrist 10 is secured at its other end to the arm 15 of a robot (not shown). Three pneumatic lines are joined to the wrist, line 16 communicates with an air bearing port; line 18 communicates with an alignment port; and line 20 communicates with a locking port.
Referring to FIG. 2, the wrist 10 comprises a housing 22 having an outer cylindrical wall 24 and an inwardly extending support plate 26 which bisects the wrist 10. An inner cylindrical wall 28 is concentrically aligned with the outer cylindrical wall 24 and is joined to the support plate 26.
Referring to FIG. 4, the outer cylindrical wall includes three ports, an air bearing port 30, an alignment port 32, and a locking port 34. Only ports 30 and 34 are shown in FIG. 2; port 32 is shown in FIG. 3.
The plate 26 is characterized by a central aperture therein through which aperture passes a tube 36. The air bearing port 30 communicates with the tube 36 through a tap hole 38. Lateral passageways 39 are formed in the outer wall 24 and also communicate with the port 30.
The locking port 34 communicates with a passage way 40 formed in the plate 26 via a tap hole 42.
Referring to FIG. 3, the alignment port 32 communicates with a passageway 44 in the plate 26 via a tap hole 46.
In the following description, only one side of the wrist 10 will be described in detail, in that, the parts are identical in each half of the wrist. Slideably received within the inner cylindrical wall 28 is a locking piston 50. The piston 50 includes a shoulder portion 52, the outer surface of which contacts in sliding engagement the inner surface of the inner cylindrical wall 28. An O-ring seal 54 is received in the lower portion of the shoulder 52. The lower portion of the shoulder 52 includes tap hole 64, which communicates with the groove in which the O-ring 54 is secured. The piston 50 is characterized by a central aperture 56, having a necked portion 58. A spring 60 biases the piston 50 outwardly against a retaining ring 62. Disposed between the retaining ring 62 and the neck portion 58 of the piston 50 is an O-ring seal 97.
Secured to the outer cylindrical wall 24 is a dome-shaped socket 80. The socket includes a passageway 82 and a groove 84. The passageway 82 is in communication with the lateral passageway 39 of the air bearing port 30; and the groove 84 circumscribes the inner surface of the socket 80.
A hemispherical link 90 is characterized by a dome-shaped recess 92 which contacts the piston 50. The link 90 terminates in a flanged end 94, which may be secured to either a gripper or to the robot arm as desired.
Disposed between the inner and outer cylindrical walls 24 and 28 is an alignment ring 70. The alignment ring includes an O-ring seal 72. Formed in the base of the ring 70 is a tap hole 74 which intersects a passageway 76. The passageway 76 communicates with the groove within which the O-ring seal 72 is received. The alignment ring 70 is adapted for fluid tight reciprocating motion between the inner and outer cylindrical walls 28 and 24 respectively. The use of pneumatic lines to pressurize a chamber or create a vacuum in a chamber, the associated solenoid valves to open and close the lines and the controls necessary to actuate the valves as desired are all well known in the art and need not be described in detail.
The operation of the invention will be described in reference to the handling of a workpiece, which workpiece at a workstation will require a stamping operation by a press. The acquisition of the workpiece and the movement of the workpiece to and from the workstation is accomplished by prior art robots. The wrist 10 is secured at one end to the robot arm 15 such as a Unimation Inc., model 560 PUMA robot. The gripper 12 is secured to the other end.
The wrist functions in three modes, an air bearing mode, a locking mode and an alignment mode. In the air bearing mode, the air bearing port 30 is pressurized and the locking port 34 and the alignment port 32 are vented to ambient. In this mode, the two links 90, as will be described, are supported on air bearings. In the locking mode, the locking port 34 is pressurized while the air bearing port is vented to ambient. In the alignment mode the alignment port 32 is pressurized, the air bearing port 30 is pressurized; the locking port 34 is vented to ambient, this results in the links being aligned in a standard relationship. After alignment, the device may remain in the air bearing mode or placed in the locking mode as desired. The workpiece is acquired by the gripper 12 with the workpiece being clamped between the fingers of the gripper. At this time, the flanges 94 of the links 90 are in parallel relationship and the wrist 10 is in its locking mode. That is, pressurized air through pneumatic line 20 is introduced into the locking port 34, the tap hole 42 and passageway 40. This pressure drives the piston 50 outwardly, the piston engaging the recess 92 of the link 90 and thus locking the link 90 in a stable position. Pressurized air also flows through tap hole 64 ensuring the O-ring 54 maintains a proper seal. At this time, the air bearing port and alignment port are vented to ambient.
The workpiece is moved to a workstation where the workpiece is placed in a recess or the like, for a stamping operation. Even if it has been properly placed in the recess, there will still occur a transmission of forces passing through the robot arm, if the wrist remains in the locking mode. Accordingly, prior to the stamping operation the wrist 10 is placed in its air bearing mode. In this mode, the locking port 34 is vented to ambient and pressurized air flows through the air bearing port 30 lateral passageway 39 and into passage 82 and groove 84 in the socket 80. The groove 84 in the socket 80 forms with the outer surface of the link 90 a passageway from which the air is dispersed forming an air bearing surface between the link 90 and the socket 80. The pressurized air also flows through tap hole 38, through the tube 36, and is dispersed between the concave surface 92 of the link 90 and the outer surface of the piston 50. This forms an air bearing surface between the piston and underside of the link 90. In this mode, both links are adapted for relative angular movement and thus when the stamping operation is performed the wrist can absorb any vibration transmitted through the gripper to the wrist. Alternatively, the fingers of the gripper could be released or relaxed further absorbing vibration forces directly along its symmetry axis.
After the stamping operation, the wrist is preferably placed in the locking mode, as previously described, with the air bearing port vented to ambient and the workpiece removed from the workstation.
If it is desired to re-align the wrist it is then placed in the alignment mode. The wrist is placed in the air bearing mode with the locking port vented to ambient. Line 18 is pressurized and air enters the alignment port 32 shown most clearly in FIG. 3. The air flows through the tap hole 46 and the passageway 42, and is discharged between the inner and outer cylindrical walls 28 and 24 respectively and the underside of the alignment ring 70. Further, as shown in FIG. 2, air enters tap hole 74 and passageway 76 ensuring that the O-ring 72 maintains a proper seal. This mode results in the alignment rings being driven toward the bases of the links, contacting the links and moving the links to alignment with the flanges being in parallel relationship and the longitudinal axes of the links being coincident. Subsequently, the locking mode is activated, the alignment port 32 vented to ambient and the locking ring retracted to a withdrawn position, as shown in FIG. 3, right side. This withdrawal can either be by applying a vacuum to line 18 by use of a spring (not shown) or by simply allowing the ring to slide back when the positive pressure is removed from the alignment port 32.
The opening and closing of the solenoid valves to ensure the control of the flow of pressurized air to the various ports and the venting of ports to ambient can be accomplished in any desired fashion. That is, depending upon the workpiece being handled when and for how long the alignment mode, the air bearing and the locking modes are required will depend upon the specific task which must be performed on the workpiece.
As compared to serial, cable controlled devices such as those used to position dial indicators and the like, the wrist has several important advantages such as a short moment arm which is important for robots with rotary joints as angular errors are transformed into position errors through the length of the moment arm. Further, the low friction allows the device to passively accommodate forces without transmitting those forces back to the robot arm itself. Lastly, rapid response is achieved which is important when the accommodation has to be made during or within a very short time frame. The use of air bearings enhances the low friction and rapid response characteristics of the wrist and results in low mass and inertia effects which is consistent with the objective of rapid accommodation.
In the description of the preferred embodiment the wrist per se accomodated five (5) degrees of freedom, 2 in position and 3 in rotation. The ability to relax the gripper provided a sixth (6th) degree of freedom, 1 in position, with the result that movement was completely arbitrary. The sixth degree of freedom could otherwise be accomplished by those skilled in the art. For example, the link could be adapted for telescopic motion along its longitudinal axis. | 4y
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This application is a divisional of application Ser. No. 08/579,665 filed on Dec. 27, 1995, now U.S. Pat. No. 5,971,192.
FIELD OF THE INVENTION
The present invention relates generally to bathroom accessories, and more particularly, to bathroom accessories securable to a bathroom wall having at least one chamber for toiletry items and orifices for receiving toothbrushes.
BACKGROUND OF THE INVENTION
A typical household bathroom is a small and confined place. Accordingly, there is a limited amount of available storage space for items needed while in the bathroom. As a result, most household bathrooms quickly become disorganized and cluttered, making it difficult, time-consuming and inconvenient to locate items that are needed while in the bathroom. Moreover, the bathroom becomes increasingly difficult to maintain and clean.
The present invention overcomes these and other drawbacks and provides accessories which can be conveniently stored in a bathroom and which allow for efficient use of existing bathroom space.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a bathroom accessory securable to a generally vertical surface. The accessory comprises a wall member locatable adjacent to the generally vertical surface to which the accessory is to be secured, and one or more suction cups engageable with the wall member for securing the accessory to the generally vertical surface. The suction cups have a head portion attachable to the wall member and a resilient, concave member having a circular projection. The suction cups are compressable against the generally vertical surface to secure the bathroom accessory to the generally vertical surface. The invention according to this application is a bathroom accessory which is made from plastic, and includes walls defining at least one chamber for holding toiletry items, transverse walls defining orifices for toothbrush handles or razor handles, and a rear engagement wall for holding suction cups to secure the accessory to a vertical wall.
It is an object of the present invention to provide bathroom accessories which make efficient use of space available in a bathroom.
It is another object of the present invention to provide bathroom accessories which are suitable for use inside a shower.
It is another object of the present invention to provide bathroom accessories which can be conveniently relocated within a bathroom.
An object of the invention is to provide a bathroom accessory for attachment to a vertical surface having at least one chamber for holding toiletry items and vertical orifices for holding toothbrushes and/or razors.
It is another object of the present invention to provide a shower basket for holding various bathroom items, which is conveniently securable to a generally vertical surface.
It is still another object of the present invention to provide a shower and tub caddy which is conveniently securable to a generally vertical surface.
It is still another object of the present invention to provide a shower and tub organizer which is conveniently securable to a generally vertical surface.
It is yet another object of the present invention to provide a toothbrush storage unit which is conveniently securable to a generally vertical surface.
These and other objects will become apparent from the following description of preferred embodiments of the present invention taken together with the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take physical form in certain parts and arrangement of parts, preferred embodiments of which will be described in detail in the specification and illustrated in the accompanying drawings which form a part hereof, and wherein:
FIG. 1 is a front plan view of a squeegee member illustrating a preferred embodiment of the present invention;
FIG. 2 is a side plan view of the squeegee shown in FIG. 1;
FIG. 3 is a rear plan view of the squeegee shown in FIG. 1;
FIG. 4 is an end plan view taken along line 4 — 4 of FIG. 1;
FIG. 5 is a top plan view of a basket illustrating another preferred embodiment of the present invention;
FIG. 6 is a front plan view of the basket shown in FIG. 5;
FIG. 7 is a side plan view of the basket shown in FIG. 5;
FIG. 8 is a top plan view of a first tray illustrating another preferred embodiment of the present invention;
FIG. 9 is a front plan view of the tray shown in FIG. 8;
FIG. 10 is a bottom plan view of the tray shown in FIG. 8;
FIG. 11 is a side plan view of the tray shown in FIG. 8;
FIG. 12 is a top plan view of a second tray illustrating another preferred embodiment of the present invention;
FIG. 13 is a front plan view of the tray shown in FIG. 12;
FIG. 14 is a bottom plan view of the tray shown in FIG. 12;
FIG. 15 is a side plan view of the tray shown in FIG. 12;
FIG. 16 is a top plan view of a corner shelf illustrating another preferred embodiment of the present invention;
FIG. 17 is a side plan view along the direction of line 17 of FIG. 16;
FIG. 18 is a bottom plan view of the corner shelf shown in FIG. 16;
FIG. 19 is a top plan view of a holding member illustrating another preferred embodiment of the present invention;
FIG. 20 is a rear side view of the holding member shown in FIG. 19;
FIG. 21 is a bottom plan view of the holding member shown in FIG. 19; and
FIG. 22 is a side view of the holding member shown in FIG. 19 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings wherein the showing is for the purpose of illustrating preferred embodiments of the invention only, and not for the purpose of limiting same, FIGS. 1-4 show a T-shaped squeegee 10 according a preferred embodiment of the present invention. Squeegee 10 is generally comprised of handle portion 20 , an arm portion 30 , and a wiper blade 40 . Handle portion 20 is comprised of a generally planar elongated upper section 22 and a generally planar lower section 28 . Upper section 22 and lower section 28 are at a slight angle relative to each other (see FIG. 2 ). Upper section 22 includes an annular depression 24 , as best seen in FIG. 1. A hole 26 is provided at the center of annular depression 24 , the hole dimensioned to receive suction cup 50 , which will be discussed in greater detail below. It will be appreciated that annular depression 24 is formed on both the front side of upper section 22 shown in FIG. 1, as well as the rear side of upper section 22 shown in FIG. 3 . Annular depressions 24 reduce the depth of hole 26 . In addition, upper section 22 has a curved top 23 .
Lower section 28 extends between upper section 22 and arm portion 30 . While lower section 28 is generally coplanar with arm 30 , it is at a slight angle relative to upper section 22 , as best seen in FIG. 2 . Furthermore, as shown in FIGS. 1 and 3, handle portion 20 tapers from the top of upper section 22 to the bottom of lower section 28 .
Arm portion 30 is comprised of an arched section 32 and a rectangular blade-receiving section 34 . Arm portion 30 extends transversely to handle portion 20 . Blade-receiving section 34 includes a slot 36 for receiving a wiper blade 40 (see FIG. 4 ).
Suction cup 50 is a conventional suction cup used to support squeegee member 10 on a generally vertical surface. The vertical surface is preferably a smooth flat surface such as glass, mirror (e.g., a bathroom mirror), tile (e.g., a bathroom wall), fiberglass, or metal.
Suction cup 50 is comprised of a concave member 52 and a head 56 . Concave member 52 includes a tab 54 . By lifting and pulling tab 54 , suction cup 50 can be easily removed from a vertical surface. Concave member 52 has a diameter of approximately 2-¾ inches. Head 56 has a generally cylindrical shape and has a length sufficient to extend through hole 26 of handle portion 20 . Head 56 has a diameter dimensioned to be receivable by hole 26 of handle portion 20 . Handle portion 20 is removable from suction cup 50 by disengaging hole 26 from head 56 . Accordingly, squeegee member 10 can be removed from suction cup 50 during use, and returned thereto for convenient storage.
The preferred dimensions in each of two sizes of squeegee member 10 will now be described. In the smaller version of squeegee member 10 , handle portion 20 has a length of approximately 6 inches and a width of approximately 1-{fraction ( 1 / 2 )} inches; arm portion 30 has a length of approximately 1-½ inches, and a width of approximately 8 inches; wiper blade 40 has a length of approximately 1 inch and a width of approximately 8 inches. However, it should be noted that only approximately ½ inch of wiper blade 40 extends outward from slot 36 . The total weight of the smaller version of squeegee member 10 , not including suction cup 50 , is about 35 ounces. In its larger version, squeegee member 10 has a handle portion 20 of a length of approximately 6 inches and a width of approximately 1-½ inches; its arm portion 30 has a length of approximately 1-½ inches and a width of approximately 12 inches. Blade 40 has a width of approximately 1 inch and a width of approximately 12 inches. The other dimensions are the same for both the small and large versions of squeegee member 10 . The weight for the larger squeegee member 10 without the suction cups is about 4.0 ounces. Squeegee member 10 is preferably constructed of plastic.
Squeegee member 10 has a variety of uses, including the removal of water and fog from glass or mirrored surfaces.
Referring now to FIGS. 5-7, there is shown a basket 60 , particularly suitable for use as a shower basket for storage of items, such as shampoo, conditioner, soap and sponges. Basket 60 is generally comprised of a front side wall 62 a , rear side wall 62 b , end walls 72 , and a floor 76 . Front side wall 62 a includes a plurality of apertures 66 . Apertures 66 allow water to drain from basket 60 , and allow items stored inside basket 60 to be identified. Rear side wall 62 b includes a plurality of holes 64 . Holes 64 are dimensioned to receive a suction cup 50 ′, which is similar to suction cup 50 described above. Suction cup 50 ′ is generally comprised of a concave member 52 ′ and a head 56 ′. Concave member 52 ′ is the same as concave member 52 , except it lacks the optimal tab 54 . Head 56 ′ is similar to head 56 ′, but includes a locking portion 58 ′ at the end of heat 56 ′ opposite concave member 52 ′. Locking portion 58 ′ has a diameter greater than the other parts of head 56 ′. Accordingly, locking portion 58 ′ engages with the inner surface of rear side wall 62 b to secure suction cup 50 to basket 60 . Accordingly, if basket 60 is removed from a flat surface to which it is attached, basket 60 will not become separated from suction cup 50 ′. Furthermore, the force exerted to remove basket 60 will also remove suction cup 50 from the flat surface. Therefore, tab 54 is not required.
End walls 72 are generally U-shaped and connect side walls 62 a and 62 b . A rim 75 is formed along the upper perimeter of walls 62 a , 62 b and 72 . Floor 76 includes drainage apertures 78 which allow fluid to drain out from the interior of basket 60 .
It will be appreciated that basket 60 is mountable to a generally vertical surface using suction cups 50 ′, the surface preferably being a smooth flat surface, such as glass, mirror, tile, fiberglass or metal The preferred dimensions of basket 60 will now be described. Side walls 62 a and 62 b have a width of approximately 6-¾ inches and a height of approximately 6 inches; end walls 72 have a width of approximately 3-½ inches and a height of approximately 6 inches. The interior dimensions of basket 60 are approximately 10 inches×3 inches×6 inches. The total weight of basket 60 , excluding the weight of suction cups 50 ′, is approximately 11 ounces. Basket 60 is preferably constructed of plastic.
Referring now to FIGS. 8-11, there is shown a tray 80 , particularly suitable for use as a shower and tub caddy, for storing items such as shampoo, conditioner, soap and sponges. Tray 80 is generally comprised of a front side wall 82 , a rear side wall 84 , an engagement wall 86 , and a floor 100 . End walls 94 are generally U-shaped and connect front side wall 82 to rear side wall 84 . A rim or lip 98 is arranged along the upper perimeter of front side wall 82 , rear side wall 84 and end walls 94 .
Engagement wall 86 , as best seen in FIG. 10, is a generally planar wall arranged adjacent and generally parallel to rear side wall 84 . Holes 88 are formed in engagement wall 86 to receive head 56 ′ of suction cups 50 ′. Connecting member 90 connects engagement 86 with rear side wall 84 .
Floor 100 includes a plurality of drainage apertures 102 and a plurality of dimples 104 . Drainage apertures 102 provide an opening for the drainage of fluid from the interior of tray 80 . Dimples 104 provide a friction surface for floor 100 .
Front side wall 82 , rear side wall 84 , end walls 94 and floor 100 define a chamber 108 . Chamber 108 preferably has a height of approximately 2 inches, a maximum length of approximately 15 inches, and a maximum width of approximately 3-½ inches. The dimensions of chamber 108 are best suited for the storage of toiletry items, such as shampoo bottles, conditioner bottles, sponges and soap.
Tray 80 is mountable to a generally vertical surface by engaging suction cups 50 with holes 88 in engagement wall 86 . Suction cups 50 ′ are then placed adjacent to the vertical surface and an appropriate pressure is applied thereto by pressing suction cups 50 ′ against the surface.
The preferred dimensions of tray 80 will now be described. Front side wall 82 and rear side wall 84 preferably have a width of approximately 10-½ inches and a height of approximately 2 inches (including the height of lip 98 ); and end walls 94 have a width of approximately 4 inches and a height of approximately 2 inches (including lip 98 ); engagement wall 86 has a width of approximately 10-¾ inches and a height of approximately 2 inches. The approximate interior volume of chamber 108 is 84 cubic inches. The total weight of tray 80 (excluding suction cups 50 ) is approximately 8.0 ounces. Tray 80 is preferably constructed of plastic.
Referring now to FIGS. 12-15, there is shown a second tray 110 particularly suitable for use as a shower and tub organizer, for storing items such as shampoo, conditioner, shaving cream, toothbrushes, razors and soap. Tray 110 is generally comprised of two side chambers 148 and a center chamber 143 . Side chambers 148 are defined by front side wall portions 112 , rear side wall portions 114 , end walls 124 , center walls 130 , and floors 132 . End walls 124 are generally U-shaped, and connect front side wall portions 112 with rear side wall portions 114 . Center walls 130 are generally transverse to front side wall portions 112 and rear side wall portions 114 , and connect side wall portions 112 and 114 with each other. Furthermore, center walls 130 define a center chamber 143 , which will be described in detail below. Floors 132 include a plurality of drainage apertures 134 and dimples 136 . Drainage apertures 134 provide openings for the drainage of fluid from the interior of side chambers 148 . Dimples 136 provide a high friction surface.
Center chamber 143 includes an upper horizontal wall 138 and a U-shaped wall 142 . Upper horizontal wall 138 includes a plurality of holes 140 . Holes 140 are preferably dimensioned to receive the handle end of a toothbrush or razor. U-shaped wall 142 includes a plurality of slots 144 for drainage of fluid from center chamber 143 . The portion of center chamber 143 defined by U-shaped wall 142 is preferably dimensioned to receive a bar of soap.
It should be appreciated that a lip 128 extends around the outer edge of chambers 148 and 143 , as best seen in FIGS. 12 and 13.
An engagement wall 116 is arranged adjacent and generally parallel to rear side wall portions 114 (see FIG. 14 ). Engagement wall 116 has a generally planar surface and includes holes 118 which are dimensioned to receive head 56 ′ of suction cup 50 ′. Engagement wall 116 has a preferred width of approximately 10-¾ inches and a preferred height of approximately 2 inches. A connecting member 120 , as best seen in FIGS. 14 and 15, connects engagement wall 116 with rear side wall portions 114 .
Tray 110 is mountable to a generally vertical surface in the same manner as tray 80 .
Side chambers 148 are preferably 4-½ inches by approximately 3-½ inches, and has a depth of approximately 2 inches (including lip 128 ). Center chamber 143 is preferably a length of approximately 4-½ inches by approximately 3-½ inches, with a maximum depth of approximately 1-¾ inches (including lip 128 ). Tray 110 has a weight of approximately 7.5 ounces and is preferably constructed of plastic.
Referring now to FIGS. 16-18, there is shown a corner shelf 150 , particularly suitable for the storage of items such as shampoo, conditioner, shaving cream, toothpaste and razors. Corner shelf 150 is generally comprised of a first side wall 152 , a second side wall 154 , engagement walls 156 , a front wall 160 and a floor 170 . First side wall 152 and second side wall 154 are arranged generally perpendicular to each other as shown in FIGS. 16 and 18. Front wall 160 is a curved wall, and connects first side wall 152 with second side wall 154 . A pair of generally planar engagement walls 156 are arranged adjacent and generally parallel to first and second walls 152 and 154 , as best seen in FIG. 18 . Each engagement wall 156 has Three holes dimensioned to receive a suction cup 50 ′.
A lip 168 is arranged along the perimeter of first side wall 152 , second side wall 154 and front wall 160 . Engagement walls 156 are integrally attached to lip 168 , as shown in FIG. 1 &
First side wall 152 , second side wall 154 , front wall 160 and floor 170 define a chamber 178 . Floor 170 includes drainage apertures 172 and 172 ′, as well as dimples 174 . Drainage apertures 172 and 172 ′ provide a means for draining fluid from the interior of chamber 178 . It should be appreciated that drainage aperture 172 may also be dimensioned to receive the handle end of a razor for storage of the razor inside chamber 178 . In this respect, drainage apertures 172 may have a larger diameter than drainage aperture 172 ′. Dimples 174 provide a high friction surface.
Corner shelf 150 is mountable to a pair of generally perpendicular vertical surfaces using suction cups 50 ′. Accordingly, corner shelf 150 is arrangeable within a corner area formed by the two generally perpendicular vertical surfaces.
Side walls 168 and engagement walls 156 preferably have a width of approximately 9 inches. Curved front wall 160 has a height of approximately 1-½ inches (including lip 168 ) and is along a radius of curvature of approximately 9 inches. Side walls 168 and 169 and curved front wall 160 preferably have a height of approximately 1-½ inches (including lip 168 ). Corner shelf 150 preferably has a weight of approximately 8 ounces (without suction cups 50 ′). Corner shelf 150 is preferably constructed of plastic.
Referring now to FIGS. 19-22, there is shown a holder 180 particularly well suited for storage of items such as toothpaste and toothbrushes. Holder 180 is generally comprised of a front side wall 182 , a rear side wall 184 , end walls 186 , floor 188 and an extension portion 200 . Front side wall 182 , rear side wall 184 , end walls 186 and floor 188 define an oval-shaped chamber 218 . Front side wall 182 and rear side wall 184 are curved walls which are connected to each other by end walls 186 . Floor 188 includes holes 190 for draining fluid from chamber 218 .
A generally planar horizontal extension portion 200 extends from the upper perimeter of walls 182 , 184 and 186 . Extension portion 200 includes holes 202 , which are preferably dimensioned to receive the handle end of a toothbrush. A generally planar engagement wall 206 attaches to extension portion 200 , as best seen in FIG. 21 . Openings 208 and 208 ′ are formed in engagement wall 106 . Openings 208 and 208 ′ are dimensioned to receive, respectively, suction cups 50 ′ and 50 ″.
It should be appreciated that suction cup 50 ″ is a modified version of suction cup 50 ′. In this respect, suction cup 50 ″ has a diameter of approximately 1-¾ inches and an enlarged locking portion 58 ″. The widest portion of opening 208 ′ (see FIG. 20) is dimensioned to receive locking portion 58 ″ therethrough.
Holder 180 is mountable to a generally vertical surface using suction cups 50 ′ and 50 ″.
Chamber 218 preferably has a height of approximately 3 inches, a maximum length of 3 inches, and a maximum width of approximately 2-¼ inches. Furthermore, holder 180 has a weight of approximately 2.5 ounces. Holder 180 is preferably constructed of plastic.
The foregoing description is directed to specific embodiments of the present invention. It should be appreciated that these embodiments are described for purposes of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof. | 4y
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RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
CROSS-REFERENCE TO RELATES APPLICATION
This invention is relates to the subject matter of a U.S. Air Force assigned patent application filed of even date herewith, titled "Low Impedance Filter Battery with Effective Electrolyte Seal" and identified as docket number AF 16775, and by U.S. Patent and Trademark Office (PTO) Ser. No. 06/792,099 now U.S. Pat. No. 4,650,733.
BACKGROUND OF THE INVENTION
This invention relates to the field of electric wave filters usable in power supply apparatus having a combination of pulsating load currents and limited supply currents. The described invention is particularly useful in satellite and other weight and volume limited environments.
Electrical energy storage in capacitor elements such as the common electrolytic capacitor frequency achieves an energy storage density in the order of 1 joule per pound of capacitor weight. For many presently feasible space shuttle and military space missions, this storage density in an electrical filter element provides a severe limitation as to the type of space mission that can be undertaken.
By way of example, the first man-made satellite, the Russian Sputnik launched in the late 1950's, employed a modest battery-powered electrical system which was capable of operating the satellite for a few weeks of time, but which nevertheless accounted for over one third of the satellite's overall weight. In the intervening twenty-five-plus years, launchable payloads have increased significantly in size, and improved space energy sources have become available. Even with present technology, however, the use of satellite systems having power supplies in range of 50 kilowatts (KW) is limited to low earth orbit because of the inability to transport systems of this electrical size and weight into higher orbit. A significant improvement in power supply weight will therefore contribute noticeable to the ability to place systems of this power level in higher orbit and enable the achievement of proposed systems having electrical capabilities in excess of 100 kw.
Electrical filtering is a necessary component in these larger power supplies as well as in power supplies of more modest capability. Electrical filters including energy storage capacitor elements are necessary, for example, in power supply waveform correcting, energy storage between pulses from an energy source, energy storage or buildup between high energy dumping events as might occur in a pulsed laser weapon, for example, and possibly for energy storage during the non-illuminated portion of a dark/light solar exposure cycle.
Under certain conditions as described subsequently herein, it is feasible to provide up to a tenfold increase in power supply energy filter storage density over the values described above using a different approach from that of the common electrolyte capacitor. In some proposed high-energy satellite applications, energy storage improvements of this capability would, for example, provide a satellite weight savings in the range of two to three tons of system payload. A central portion of this improvement resides in an optimized application of a rechargeable or secondary battery such as the nickel cadmium battery as an energy storing electrical filter element. In addition to the indicated considerations of energy storage density, such factors as battery service life, the imposed depth of discharge and the physical properties of battery filter cells require attention in embodying an electrical filter having these improved characteristics.
The patent art discloses several examples of battery cells usable for meeting a variety of battery requirements and their manufacture. Included in this art is the patent of Brijesh Vyas, U.S. Pat. No. 4,471,038, which concerns an alkaline battery cell, preferably a nickel-cadmium cell, which is improved through the addition of organic polymer compounds to one of the cell electrodes.
The patent art of interest also includes the patent of Margaret A. Reid, U.S. Pat. No. 4,439,465, which concerns a method for making a lightweight battery substrate or plaque that is also usable in a fuel cell.
The patent of Claude J. Menard, U.S. Pat. No. 4,154,908, concerns a electrode configuration for alkaline batteries wherein shapes enabling the use of unequal electrode material amounts on electrodes of different polarity are used--in order to obtain an improved life cycle and superior volumetric energy density. The Menard patent principally concerns silver-zinc, silver-cadmium, and nickel-zinc batteries. The Menard patent also teaches the use of potassium hydroxide as an electrolyte, and is concerned with increasing the number of discharge cycles and the depth of discharge characteristics of a battery. The Menard patent is especially concerned with electrode shape change or the migration of active material between different regions of an electrode.
The patent of Gunter Gutmann, U.S. Pat. No. 4,215,184 concerns an improved arrangement for nickel-oxide/hydrogen battery cells which achieves improved heat transfer in the axial direction of the cell through a reduction of the number of stacked elements in a cell.
The patent of David H. Fritts et al, U.S. Pat. No. 4,242,179, concerns a method for fabricating cadmium electrodes usable in nickel-cadmium and silver-cadmium batteries, for example. The Fritts patent achieves an improved loading of the cadmium material without surface buildup and also eliminates some of the electrode processing steps previously required.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a lightweight, small-size, energy storing filter network element.
Another object of the invention is to provide a filter network element having better stored energy versus voltage characteristics than are afforded by the conventional electrolytic filter capacitor.
Another object of the invention is to provide an energy storage arrangement suitable for use in space satellites and other volume limited, weight limited applications.
Another object of the invention is to provide an electrical filter network element capable of storing energy for varying amounts of time between the asynchronized high current pulses supplying and utilizing the energy.
Another object of the invention is to provide an electrical filter network arrangement capable of the improved supplying of energy to a load during brief periods of source interruption.
Another object of the invention is to provide an electrical filter network arrangement capable of high density lightweight energy storage in combination with an extended life number of energy receiving, and energy dumping cycles.
Additional objects and features of the invention will be understood from the following description and the accompanying drawings.
These and other objects of the invention are achieved by an energy utilizing apparatus which includes a source of direct current energy pulses, an electrical load of pulsating electrical current requirements connected with the energy source, a rechargeable electrochemical battery of low internal impedance with respect to the source of energy and connected in electrical shunt with the source and the pulsating current load for collecting energy from the source and delivering energy to the load to supplement the supply during periods of load demand, the collecting and delivering being at a fixed predetermined battery terminal voltage and in pulses and pulsations having energy content less than one one-hundredth of the total energy capacity of the battery.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an earth satellite arrangement of a type desirably utilizing the present invention.
FIG. 2 is an electrical element representation of a battery filter element made in accordance with the invention.
FIG. 3 is an electrical circuit usable with a battery filter element made in accordance with the invention.
FIG. 4 is a group of electrical waveforms describing operation of the FIG. 3 circuit.
DETAILED DESCRIPTION
Earth satellites have become accepted tools for use in the communications art and are becoming increasingly important for use as weapons platforms, sites for manufacturing, scientific inquiry and other proposed uses. Since most of these uses of a satellite vehicle require the availability of electrical energy in significant quantities, and since the deployment of such satellites involves the use of limited capability and expensive rocket devices, improvements in the electrical energy supply apparatus used in such satellites are of intense technical and military interest.
FIG. 1 shows an earth satellite of the described type as it might appear to an observer located in space. In FIG. 1 the earth's sun is indicated at 104, the earth at 102, and an earth orbit residing satellite vehicle at 100. The satellite 100 in FIG. 1 is intended to contain one or more systems such as optical energy emitters or radio frequency energy emitters connected to a plurality of energy radiating devices or antennas 110, 112 and 114. The satellite 100 is presumed to be of the extended energy type and to therefore utilize internally sourced energy or to collect energy in the form of solar radiation on an array of solar cell panels which are disposed over the satellite surface, as indicated at 106. Solar collectors may also be disposed over the end surfaces of the satellite as indicated at 118, where the orbit and orientation patterns of the satellite 100 with respect tot he sun 104 are appropriate.
Electronic apparatus included in the satellite vehicle 100 may typically include a radio frequency or radar transmitter, a computer, mechanically actuated devices, and other apparatus having pulsating load current requirements. The current pulsations of such load systems frequently temporarily exceed the current delivering ability of the available energy source, such as the solar panel array. The energy delivered by the array of solar cell panels 106, 108, and 118 can also be subject to pulses or fluctuations as the satellite vehicle moves in orientation, moves around the earth and around the sun; such energy pulses can also result from shadows cast on the array of solar panels by other space objects such as the earth's moon or an intervening planet or from changes in orientation of the solar cell panel arrays with respect to the sun. In such events, some energy storage arrangement is desirable in order that the satellite vehicle load be capable of independent function in response to conditions other than energy availability.
In accordance with the present invention, the satisfying of load pulsations and energy source interruption pulses and the accommodation of energy source waveform variations is preferably achieved through the use of power supply filtering elements in the satellite vehicle 100 which are of improved lightweight high energy density capability. These filtering elements are preferably arranged in the form of a secondary or rechargeable electrochemical battery of the type described in the above referenced U.S. Air Force patent application, docket number AF 16775, PTO Ser. No. 06/792,099, which is hereby incorporated by reference herein. Other battery arrangements, especially arrangements providing for the short and direct current flow paths incidental to low electrical impedance, and long battery operating life, along with small physical size and weight could of course, be employed in the FIG. 1 satellite vehicle. Conversely, other settings outside of the space environment can also benefit from the presently disclosed invention.
A secondary cell battery such as the nickel-cadmium alkaline cell battery, when connected to a pulsed source of electrical energy or a pulsating load current device, displays electrical characteristics which differ sharply from those of the usual electrolytic capacitor filter element, characteristics which can be represented by the electrical elements shown in FIG. 2 of the drawings. The FIG. 2 electrical elements include two series connected, parallel path networks 200 and 202 including the four electrical nodes 204, 206, 208, and 210 also labeled N1, N2, N3, and N4. The nodes 204 and 210 are connected with the battery positive and negative terminals 212 and 214 respectively, so that the node 204 and the terminal 212 have the same electrical potential and the node 210 and terminal 214 have the same electrical potential. Other electrical elements in the FIG. 2 representation include a pair of voltage sources 218 and 224 representing the voltage developed between the positive electrode and the battery electrolyte and the voltage developed between the electrolyte and the negative electrode i.e., the nickel and cadimum electrodes, respectively, in the case of the aforementioned nickel-cadmium batery cell. The electrical resistances R1 and R2, 216 and 222 respectively in FIG. 2, represent the ionic and activation resistances present at the nickel and cadmium electrodes of the representative nickel-cadmium battery respectively. The capacitors C1 and C2, 220 and 226 respectively in FIG. 2, incorporate electrode double layer capacitances into the FIG. 2 battery representation. The resistance R3, 228 in FIG. 2, corresponds to the ohmic resistance through the electrolyte and electrode conductors of the battery cell. The FIG. 2 electrical representation corresponds to one cell of a multiple celled battery which is preferably used in the FIG. 1 apparatus, additional battery cells are representable by additional networks of the FIG. 2 type or alternately by modification of the numeric values assigned to the FIG. 2 elements.
Additional details concerning the FIG. 2 battery and other information relating to the present invention are included in a technical report titled "Pseudo Bipolar Nickel-Cadmium Batteries Used as Filter Elements to Pulsed Current Loads" authored by Michael B. Cimino and Gregory M. Gearing, of the Energy Conversion Branch, Aerospace Power Division of the Aero Propulsion Laboratory, Air Force Weight Aeronautical Laboratories, Air Force Systems Command, Wright-Patterson ABF OH, 45433. The Cimino and Gearing report is identified as AFWAL-TR-84-2094 and also as a thesis submitted in partial fulfillment of the requirements for the Master of Science Degree at the Air Force Institute of Technology, Weight-Patterson AFB OH, 45433. Copies of this technical report may be obtained from the National Technical Information Service, from the Air Force Weight Aeronautical Laboratories (AFWAL/POOC), and in thesis form from the Air Force Institute of Technology. The contents of this technical report and thesis are hereby incorporated by reference into the present specification.
The electrical characteristics of the FIG. 2 battery cell when impressed with a direct current energy source and a pulsed load current, differ sharply from the characteristics of the conventional electrolytic filter capacitor. One of the principal differences between the FIG. 2 apparatus and the conventional capacitor concerns the constant voltage nature of the FIG. 2 apparatus as represented by the voltage sources 218 and 224, this constant voltage nature differs from the capacitor charactreistic wherein removal of energy from storage in the capacitor is accomplished by a directly related change in capacitor voltage--in accord with the equation: energy (E)=1/2 capacitance (C) x voltage (V) 2 . In contrast with this direct relationship between stored energy or charge and voltage in a capacitor, the electron and ion exchange in the FIG. 2 battery cell i.e., the faradaic mechanism in the sources 218 and 224 occurs under constant voltage conditions--at least with respect to first blush or gross effects.
The presence of the capacitors 220 and 226 in the FIG. 2 battery cell introduces a smaller magnitude transient relationship between battery voltage and energy content--a relationship in the nature of that found in the conventional electrolytic capacitor. When a nickel-cadmium battery for example, is charged, the electrolyte forms layers of charged ions near each battery electrode and each layer of charged ions is separated by water molecules which act as a capacitor dielectric medium between charge layers. These layers of charge are named the electrical double layers and ion interaction occurs predominatly in the two of these layers closest to the electrode structure.
The double-layer charge is influential in determining the initial rate of change of voltage and current when a battery is switched between the charging, standby, and discharging states and is particularly significant for batteries exposed to transient or pulsed or pulsating current conditions. A discussion of the double layer capacitance is to be found in the article "Absorption of Hydrogen and Oxygen on Electrode Surfaces" by R. F. Amile, published in the Journal of the Electrochemical Society, vol 108, p. 377, 1961 which is hereby incorporated by reference herein. Typically, double layer capacitance values range from 50 to 2200 microfarads for each square centimeter of electrode area, the higher values in this range being associated with a nickel electrode and the lower values with a cadmium electrode in a nickel-cadmium battery cell, for example.
The double-layer capacitances and faradaic mechanisms represented by the capacitors 220 and 226 and voltage sources or ideal batteries 218 and 224 respectively in FIG. 2, therefore all have different time responses or time constants during transient charging and discharging of the FIG. 2 battery apparatus. Generally the double-layer capacitances result in time constants measured in milliseconds of time, while the faradaic decay as represented by the voltage sources identifies with time constants of longer duration, times measured in minutes to hours in the presently contemplated battery arrangement. The lower value of capacitance associated with a negative or cadmium electrode provides the initial or more rapid change in battery voltage upon impression of a transient load, and this initial rapid change of battery voltage is followed by the change resulting from discharge of the larger valued nickel double layer capacitance. The two capacitor related changes are in turn followed by the conventional faradaic discharge or change of voltage supplied by the sources 218 and 224 in FIG. 2.
Battery life as measured in terms of number of charge and discharge cycles achievable before unacceptable electrical storage capacity erosion occurs in a significant consideration when a battery of the FIG. 2 type is employed in a FIG. 1 satellite vehicle or other pulsed current electrical filtering environment. In reality, battery cycle life, battery depth of discharge (DOD) and battery energy storage efficiency, that is, stored joules per pound of battery weight are a trio of interrelated factors which require combined little consideration with respect to demanding battery usage such as is contemplated herein.
Much usage of secondary battery cells, especially of the nickel-cadmium battery, has involved cycles having deep battery discharge followed by a slower recharge. Such usages as vehicle starting and standby electrical energy sourcing and even many satellite applications come within a cycle of this type. These usages may be considered to involve DOD's between roughly 15% and 80% of capacity followed by recharging at current values between one-tenth and 1.0 times the current which will completely discharge a charged battery in a time of one hour, the "C" rate current. Frequently batteries exposed to such cycles provide lifetimes of between 500 and 50,000 (5E4) cycles before the battery energy storage capacity is decreased to one-half its initial rated capacity. At a lower DOD a given battery will survive a greater number of charge and discharge cycles than at higher DOD levels--a result of internal heating and other destructive events in the charge and discharge sequence.
A battery used as a filter element in a spacecraft power system as represented in FIG. 1 clearly is required to endure more than this 5E4 charge and discharge cycles in order to be practical since even at a five cycle per second use rate, such a life represents only about three hours of battery life. Cycle lifetimes in the order of 1E9 or more are desirable for a FIG. 1 used battery filter element.
Battery life and depth of discharge in a FIG. 1 type utilization also influence battery energy density considerations, as is implied by the trio of factors concept recited above. For example, if a common 1.2 volt, 22 ampere-hour nickel-cadmium cell is operated at a DOD of 0.01% and a 5 Hz charge and discharge rate, it delivers approximately 10 joules of energy per discharge cycle. Such a cell might weigh 10 pounds and therefore provide an energy density in the order of 1 joule per pound. If, however, the cell is capable of operating at the ten times greater DOD of 0.1%, the same battery would be delivering 100 joules of energy and operating at an energy density of 10 joules per pound. The battery filter element of the above incorporated by reference copending patent application, for example, includes provisions for this type of usage and has been found capable of 1E7 operating cycles using a DOD of 0.013% and a 5 Hz cycle charge/discharge rate. This battery filter element is also capable of energy density values in the range of 40 joules per pound of weight.
FIG. 3 of the drawings shows a representative circuit in which a battery of the FIG. 2 type is operated in the manner required for a FIG. 1 used battery filter element. In FIG. 3 a battery filter element 300 is shown connected in electrical shunt with a direct current energy source 302 and a pulsating current load 304. The pulsating current load 304 may include switching transistors and dissipative elements or other apparatus known in the electronic art. Current flows in the energy source 302, the battery filter element 300, and the load 304 are measured by the current sensing elements 312, 314, and 316. Current flow from the energy source 302 is indicated by the arrow 308 in FIG. 3, while current flow to the pulsating current load is indicated by the arrow 310. The current summation node between the energy source, battery filter element, and load is indicated at 318 in FIG. 3, and a reverse current blocking diode which prevents battery discharge current from flowing through the energy source 302, is indicated at 320.
The FIG. 3 circuit is representative of both a test circuit usable for evaluating battery filter element performance and also generally of the circuit arrangement used for a battery filter element in the FIG. 1 apparatus. A practical embodiment of the FIG. 3 circuit in a FIG. 1 type satellite vehicle might omit the current sensing elements 312-316 in the interest of weight, cost and other practical considerations or alternately, might replace these elements with devices generating signals usable for telemetry or other electronic functions. Notable characteristics of the energy source 302 may include:
Limited peak current capability;
Interruptable energy supply capability, e.g., radiant energy source interruption by an object in different orbit;
Greater output voltage than the faradaic voltage of battery filter element 300;
Average current capability equal to or greater than the average current requirement of the load 304; and
Alternately, of lower current capability than the peak currents of the load 304.
The solar excited electrical energy source indicated for the satellite vehicle 100 in FIG. 1 is one example of an energy source within these characteristics; certain types of fuel cells, nuclear electrical energy sources, and even certain types of battery sources also come within these characteristics. Generally, the presence of an electrical source having lower peak current capability than the requirements of a pulsating current load device provides a suitable setting for a battery filter element in accordance with the present invention.
The electronic load 304 in FIG. 3 may comprise a laser device, a radar or radio frequency transmitter, a computer or other apparatus involving electronic energy flow control devices and capable of generating pulsating load current requirements. The pulse generator 306 may be considered in a practical embodiment of the FIG. 3 apparatus to be incorporated within the load 304 or may in a test setup, be a separate and distinct piece of signal generating equipment as indicated in FIG. 3.
The battery filter element 300 in FIG. 3 is desirably of a low internal impedance, that is, of low internal resistance and small internal inductance with respect to the effective impedance of the electronic load 304 and also preferably of low impedance with respect to the internal impedance of the energy source 302. A pseudo-bipolar battery filter element of the type described in the above incorporated by reference copening U.S. patent application provides characteristics reasonably meeting these low impedance requirements. Other battery arrangements preferably involving central rather than peripheral cell interconnection attachment could also be employed.
The interrelated concepts of battery discharge/recharge cycle life and stored energy density relating to the battery filter element 300 are described above in connection with FIG. 2. Generally for the FIG. 3 battery filter element, operation involving depth of discharge between 0.01% to 0.1% and a charge/discharge cycle life of over ten million cycles is contemplated. Improved operating principles and construction for a battery filter element will, of course, enable greater battery cycle life.
The current supplied to the load, the current 310 in FIG. 3, originates in some combination of current from the battery filter element 300 and current 308 from the energy source 302 and divides between these sources, depending on the relative source impedances involved; this division can vary nearly instantaneously with load current pulsations or pulses from the energy source 302, as is indicated in greater detail in FIG. 4 of the drawings.
In FIG. 4, current and voltage waveforms appropriate to the battery filter element of the above incorporated by reference patent application and corresponding to the FIG. 3 current identifications are shown. The waveform at 400 in FIG. 4 represents load current, and corresponds to the current I L at 316 in FIG. 3. This current is shown in the FIG. 4 example to comprise a pulse 410 of 25 amperes amplitude and 100 milliseconds time duration. Time durations for each of the waveforms in FIG. 4 are indicated along the scale 408, while amplitudes are indicated along the vertical scale adjacent each waveform as at 412 for the 25 ampere load current. The voltage applied to the load 304 in FIG. 3 is indicated in the waveform 402 of FIG. 4 and is shown to have values varying between 4.5 and 5.75 volts in different time portions of the waveform 402. Voltage amplitudes are indicated along the scale 416 which is made discontinuous or exaggerated in nature in order to emphasize the variations occurring.
The battery filter element 300 in FIG. 3 is subjected to currents according to the waveform 404 in FIG. 4. These currents include a charging current of 12.5 amperes as indicated at 424 during load removed portions of the operating cycle and a discharging current of 12.5 amperes as indicated at 426 during the load current pulse conducting time. Current flow in the energy source 302 in FIG. 3 is indicated at 406 in FIG. 4, is shown at 428 and 430 to vary about the 12.5 ampere nominal value indicated at 436, and to also include the current transients 432 and 434 at the time of load current commencing and ending.
Several of the notable features in the FIG. 4 waveforms can be related to electrical elements shown in the FIG. 2 battery filter element. The slow rise and fall of battery filter element voltage indicated at 414 and 418 respectively and the rounded voltage waveform corner 420, relate to the charging and discharging of capacitors 220 and 226 in FIG. 2. A similar rounding occurs at 422 in the battery current waveform 404. The resistances 216, 222, and 228 in FIG. 2 contribute to the slight average offsets in the battery filter element current flow in the waveform 406.
The effectiveness of a battery filter element in replacing the conventional electrolytic capacitor in a power supply including consideration of equivalent capacitances and energy storage quantitative amounts are discussed in the above incorporated by reference copending patent application. Generally for battery filter element embodiments described therein which have circular plates or electrodes of 3.3 inch diameter, centers located cell-to-cell interconnecting members, close electrode spacing and potassium hydroxide electrolyte of 32% by weight KOH concentration, characteristics of the following electrical nature obtain.
These electrical characteristics can be more precisely described in terms of multiples of the above defined "C" rate where "C" is again the value of current that will totally discharge a fully charged battery in the time of one hour.
Battery filter elements made in accordance with the described embodiment are useful in the presence of charging and discharging pulse currents up to the 25 to 35 ampere range, currents which are in excess of 18 times the C rate of the battery in the charging and loading circuit arrangement described above. The principal limitation at this rate of performance is actually electrolyte heating--to a point approaching boiling. Better electrolyte heat dissipation than is provided by the acrylic plastic cavity receptacle structure could, of course, be arranged to extend this capacity.
Operation with currents in this 25 to 35 ampere range with a four cell battery filter element and depth of discharge (DOD) values in the range of 0.05 to 0.07 also provides energy storage densities in the range of 40 joules per pound, a value some forty times greater than is achieved with electrolytic capacitors. The effective energy density increases almost linearly with DOD for values in the 0.01 to 0.08 range.
Terminal voltage for the battery filter element can be reasonably expressed over the time interval t, by the equation:
V(t)+E.sub.0 -4iR.sub.3 -4iR.sub.2 [1-exp(-t/R.sub.2 C.sub.2)]
In this equation the presence of four series connected cells is presumed and the resistances and capacitances for the nickel electrodes are neglected in view of their small magnitude with respect to cadmium electrode parameters. Symbols are defined below.
The electrical characteristics of the described embodiment battery filter element also include effective initial cell capacitance in the range of 11 farads in each of the four cells of the described battery filter element; actually double layer capacitance values of 5000 farads and 11 farads in a particular cell are to be expected, according to calculations. Since the two double layer capacitances are electrically series connected an effective capacitance, C 2 in the above equation, that is near the lower value of 11 farads is achieved.
Internal resistance values in the range of 20 to 60 milliohms for the electrolyte and electrode conductor resistances, R 3 in the above equation, and in the range of 50 to 60 milliohms for the double layer capacitance shunted resistances, R 2 in the above equation, are also to be expected from the described embodiment battery filter element. These values are for a four-cell arrangement.
At a 5C discharge rate the Faradaic component of voltage change at the terminals of the four-cell example, that is the change of voltage in the ideal battery shown in the circuit of FIG. 2 is found to be small and on the order of 0.14 millivolt. The limited magnitude of this change component allows its neglect in most considerations of the battery filter element.
By way of the low resistances, large capacitance, relatively fixed voltage, and large current handling capabilities attributable to the described battery filter element, it can be observed that desirable pulse current filtering in power supply and other electrical network locations are feasible with this component. These desirable electrical properties are, of course, in addition to the considerable weight and energy storage density improvements enabled by the described apparatus. Other characteristics of the described embodiment battery filter element including graphs and test results information are contained in either the academic thesis or the technical report identified above and incorporated herein by reference.
Modification of the described embodiment apparatus are possible to achieve even more desirable properties. The use of improved electrolyte cooling has been described above and other improvements such as in the composition and construction of electrodes and the composition and construction of cell cavity receptacles and battery filter element enclosure structures are also possible. The described embodiment has emphasized the attainment of low electrical impedances and the attainmente of these low impedances in a favorable weight and volume environment; it is of course possible to emphasize the attainment of greater energy storage capability in the battery filter element as would be desirable where the load and energy sources involved call for a standby energy reserve in the battery filter element in addition to the waveform correction heretofore emphasized. Day and night space vehicle exposure, for example, would call for modifications of this nature.
The battery filter element of the present invention therefore provides a desirable arrangement for obtaining large magnitude pulses of direct current energy in a space limited and weight limited environment as is commonly found in satellite vehicles and other present-day equipment employing electronic systems. The desirable electrical properties, reasonably long life, and moderate cost of the battery filter arrangement are also conducive to the use of such arrangements in applications which have heretofore been limited to capacitor, inductor, and other power filtering arrangements. The relatively modest energy loss characteristics of a battery filter element are also attractive for use in space satellite and other limited energy source environments.
While the apparatus and method herein described constitute a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus or method, and that changes may be made therein without departing from the scope of the invention, which is defined in the appended claims. | 4y
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RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 61/394,733, filed on Oct. 19, 2010, which is herein incorporated by reference in its entirety.
BACKGROUND
Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Photovoltaic (PV) modules are typically configured to produce electricity most efficiently from direct sunlight. Mounting hardware for PV modules has been designed to reliably mount and expose PV modules to direct sunlight by attaching them to unobstructed buildings, vehicles, or structures. While there have been a number of recent developments in the field of building integrated PV systems, there are still issues with their installation, such as ease of orientation issues, PV module alignment issues, ventilation issues, servicing issues, and inability to work well in retrofit applications.
Numerous systems have been devised to mitigate these issues, but most have resulted in costly and cumbersome mounting hardware. One such system is disclosed in U.S. Pat. No. 6,672,018 ('018) to Shingleton. The '018 patent discloses a solar collector array formed of a plurality of solar panels mounted on a frame made of support beams which may be sheet metal channel members. A butyl tape or other glazing material is applied between the back laminate of the solar panel and the beam. Clips are used to clamp the panels to the support beams. The clips have an upper portion that is generally T-shaped in profile, and a retainer in the form of a channel nut or bar, with a threaded hole that receives a bolt or similar threaded fastener. The retainer biases against the inwardly directed flanges of the channel support beam. Electrical wires and mechanical fasteners are concealed within the support beams.
Therefore, a definite need exists for a simple, cost-effective, attachment apparatus which provides the ability to secure panels to different substrates while providing ease of installation, orientation, and removal from the substrates.
SUMMARY
According to a particular aspect, an apparatus is provided for securing a panel, such as a PV panel, to a substrate.
An apparatus is provided for securing a panel to a substrate. The apparatus includes a base member, and an attachment member for securing the base member to the substrate. The apparatus further includes a clip member including a U-shaped member and an angle-sided member. The U-shaped member includes a central portion and first and second walls defining a generally U-shaped access region for accepting the angle-sided member. At least one of the first and second walls includes a longitudinal flange extending laterally outwardly from an upper end thereof. Each of the U-shaped member and the angle-sided member includes a corresponding hole for accepting the attachment member therethrough. The apparatus further includes a securing member for pressing the longitudinal flange against at top edge portion of the panel.
These as well as other aspects, advantages, and alternatives will become apparent to those of ordinary skill in the art by reading the following detailed description, with reference where appropriate to the accompanying drawings. Further, it should be understood that the disclosure provided in this summary section and elsewhere in this document is intended to discuss the invention by way of example only and not by way of limitation.
BRIEF DESCRIPTION OF FIGURES
To understand the present disclosure, it will now be described by way of example, with reference to the accompanying drawings in which:
FIG. 1 is an elevational side view of an embodiment of an apparatus for securing a panel to a substrate;
FIG. 2 is an exploded side view of the apparatus of FIG. 1 ;
FIG. 3 is an exploded perspective view of the apparatus of FIG. 1 ;
FIG. 4 is an exploded view of panels secured to a plurality of benches via a plurality of the apparatuses of FIG. 1 ;
FIG. 5A illustrates a partial perspective view of a plurality of panels secured to a plurality of benches via a plurality of apparatuses of FIG. 1 ;
FIG. 5B illustrates a partial open perspective view of the plurality of panels secured to a plurality of benches via the plurality of apparatuses of FIG. 1 ;
FIG. 6 is an exploded view of a couple of panels to be secured to an arm chair via the apparatus of FIG. 1 ;
FIG. 7A illustrates a partial perspective view of the couple of panels secured to the arm chair of FIG. 6 via the apparatus of FIG. 1 ;
FIG. 7B illustrates a partial open perspective view of the couple of panels secured to the arm chair of FIG. 6 via the apparatus of FIG. 1 ;
FIG. 8 is an elevational side view of an alternate embodiment of an apparatus for securing a panel to a substrate;
FIG. 9 is an exploded side view of the alternate embodiment of FIG. 8 ; and
FIG. 10 is a front view of a clip having only one wall extending upward; and
FIG. 11 is a side view of another alternate embodiment of an apparatus having a flange that includes teeth.
DETAILED DESCRIPTION
While the present invention may be embodied in various forms, there will hereinafter be described some exemplary and non-limiting embodiments, with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated.
In this application, the use of the disjunctive is intended to include the conjunctive. The use of definite or indefinite articles is not intended to indicate cardinality. In particular, a reference to “the” object or “a” and “an” object is intended to denote also one of a possible plurality of such objects.
Referring to FIGS. 1-3 , there is shown an embodiment of an apparatus or assembly 100 for securing a panel, such as a PV panel, to a substrate. As shown, apparatus 100 includes a clip assembly 102 and a C-shaped body, frame or clamp 104 , coupled to each other through a screw or bolt 106 . Clip assembly 102 includes clip 102 a , having a generally U-shaped structure, and an angle-sided or generally triangular member 102 b . U-shaped clip 102 a has a central portion 108 , and a pair of raised portions or walls 110 . Central portion 108 and raised walls 110 define an access region 114 . Access region 114 is accessible from two (2) longitudinal sides and from above to enable unobstructed access to triangular member 102 b and to bolt 106 . Raised walls 110 can be substantially perpendicular to central portion 108 . Alternately, raised walls 110 can extend inwardly or outwardly over central portion 108 .
Central portion 108 includes a hole 116 formed therein for receipt there-through of bolt 106 , and triangular member 102 b includes a hole 118 for receipt there-through of bolt 106 , thus facilitating the coupling of clip assembly 102 to C-shaped frame 104 via bolt 106 . Raised walls 110 include longitudinal flanges 120 extending substantially laterally away from access region 114 . Alternately, flange 120 may be configured to extend from wall 110 in a slight downward direction, instead of forming a substantially right angle with a direction of wall 110 .
C-shaped frame 104 includes a top frame portion 124 and a bottom frame portion 126 , spanned by an intermediate frame portion 128 . Bottom frame portion 126 is terminated by a bottom clamp seat 130 . Top frame portion 124 carries at its end, distant from the frame portion 128 , a threaded hole or an internally threaded housing 132 having a generally cylindrical shape. Bottom clamp seat 130 and threaded housing 132 are separated by an opening 133 , whose size is selected to be at least slightly wider that a thickness of a substrate to which a panel is to be secured.
A cross-handle 134 is slideably mounted in a transverse bore through the top end of bolt 106 , and a nut 136 is threaded on bolt 106 to be positioned between the triangular member 102 b , positioned within access region 114 of clip 102 a , and cross-handle 136 . During operation, elongated bolt 106 can adjustably penetrate through internally threaded housing 132 to press an object, such as a substrate, via a free bottom end of bolt 106 against bottom clamp seat 130 .
Now referring to FIGS. 4 , 5 A and 5 B, a plurality of assemblies 100 are used to secure a plurality of panels 402 to a plurality of benches or seating substrates 404 . As best seen in FIGS. 5A and 5B , C-shaped frames 104 and bolts 106 are used to securely affix the corresponding assemblies 100 to benches 404 . By tightening nuts 136 , clip assemblies 102 are biased, via flanges 120 , against top ends or edges of panels 402 while bottom surfaces of panels 402 are pressed against benches 404 . For this securing of panels 402 to benches 404 , triangular members 102 b are configured to have one of their respective internal angles match the vertical angle formed by an oblique straight line connecting consecutive forward edges of vertically adjacent benches 404 and a horizontal line sharing a vertical plane with the oblique straight line.
In another embodiment, triangular member 102 b is configured to include a manually adjustable internal angle. For this embodiment, triangular member 102 b may include an internal mechanism, controlled manually externally, that adjusts the adjustable internal angle so as to match it to an incline angle of the substrate to which assembly 100 is to be secured.
In yet another embodiment, triangular member 102 b is configured to include an automatically adjustable internal angle. For this embodiment, triangular member 102 b may include an internal mechanism that automatically adjusts, during operation, the adjustable internal angle to an incline angle of the substrate to which assembly 100 is being secured.
Now referring to FIGS. 6 , 7 A and 7 B, assembly 100 is used to secure a couple of panels 402 to a couple of adjacent seats 704 . As best seen in FIGS. 7A and 7B , C-shaped frame 104 and bolt 106 are used to securely affix assembly 100 to a seat arm 706 separating adjacent seats 704 . By tightening corresponding nuts 136 , clip assemblies 102 are biased, via flanges 120 , against top ends or edges of panels 402 , while bottom surfaces of panels 402 are pressed against both a forward edge 708 of seat arm 706 and a top end 710 of a seat back 712 . Triangular members 102 b , selected for this securing of panels 402 to seats 704 , have one of their respective internal angles match the vertical angle formed by an oblique straight line connecting forward edges of arm 706 and top end 710 and a horizontal line sharing a vertical plane with the oblique straight line. Alternately, as discussed above, triangular members 102 b , selected for this securing of panels 402 to seats 704 , may have a manually adjustable internal angle or an automatically adjustable angle so match the incline angle of the line connecting forward edges of arm 706 and top end 710 .
Now referring to FIGS. 8 and 9 , an embodiment of an alternate assembly 800 is shown. Assembly 800 is substantially assembly 100 augmented with an additional clip assembly 802 , an alternate bolt 806 , and an additional nut 808 . When assembly 800 is used to securely affix a panel to a substrate, clip assemblies 102 and 802 are biased against top edges and bottom edges of the panel, respectively, via nuts 136 and 808 , respectively. Clip assembly 802 is similar to assembly clip 102 , in that it includes a clip 802 a and a triangular member 802 b . Triangular member 802 b preferably has one internal angle equal to that of triangular 102 b , when they are used together to hold or capture a panel, having sides with substantially parallel edges, therebetween flanges 120 and 820 , of clips 102 a and 802 a , respectively.
Now referring to FIG. 10 , an embodiment of another alternate assembly 1000 is shown. Assembly 1000 is configured to have a different clip 1002 than that of assembly 100 . Unlike assembly 100 , assembly 1000 is configured to include only one raised wall 1110 . Assembly 1000 is configured to be used to secure an end panel to a substrate. As such, assembly 1000 includes only one flange 1020 to be in contact with the end panel.
Now referring to FIG. 11 , a side view of an embodiment of assembly 100 , 800 or 1000 is shown. Typically, a PV panel includes a circumferential frame (not shown), having a substantially U-shaped cross-section, that surrounds it preferably from all sides. To improve the securing of the panel, flanges 120 , 820 and 1020 of clips 102 a , 802 a and 1002 a , respectively, may include teeth 1101 that point substantially downward. As such, during the securing of assembly 100 , 800 or 1000 to a substrate, flanges 120 , 820 or 1020 are engaged to the circumferential frame via teeth 1101 .
In another embodiment, to ensure good grounding of a PV panel, for example, each element or member of assembly 100 is formed of conductive material or at least includes or is covered with a conductive outer surface. As such, teethed clip 102 a , bolt 106 and C-shaped frame 104 provide an electrical connection between a PV panel and a conductive supporting substrate, to ensure good grounding of the PV panel. Alternately, if the supporting substrate is formed of a non-conductive material, assembly 100 may be equipped with a grounding electrical wire (not shown) that may extend to a grounding element.
While certain embodiments of the present invention have been described, it will be appreciated that changes and modifications can be made and that other embodiments may be devised without departing from the true spirit and scope of the invention. | 4y
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This is a division of application Ser. No. 06/898,600, filed Aug. 22, 1986, now U.S. Pat. No. 4,820,689, which is a continuation of application Ser. No. 06/637,831 filed Aug. 6, 1984, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a pharmaceutical composition having antirheumatic activity, antithrombotic activity, analgetic activity, antipyretic activity, anti-hyperlipemic activity and anti-inflammatory activity and activities of reducing the level of blood sugar, raising the coronary blood flow, improving the capability of deformation of erythrocytes, reducing the blood pressure, ameliorating proteinuria and proteinemia and regulating production or metabolism of prostaglandins in a mammal, containing a glycoprotein derived from a basidiomycetous fungus belonging to the genus Coriolus, for instance, Coriolus versicolor (Fr.) Quel., as an active ingredient. The glycoprotein derived from Coriolus versicolor (Fr.) Quel. [FERM-P No. 2412 (ATCC 20547)] has been already supplied to the public as an anti-tumour drug under the trade mark of Krestin.
Since the glycoprotein is low in mammalian toxicity and does not disturb the intestinal microflora, the pharmaceutical composition containing the glycoprotein as an active ingredient can be administered for a long time period. In addition, the glycoprotein is quite free of the fear of causing malformation and/or allergic reaction and accordingly, the glycoprotein is an extremely safe substance.
The active ingredient, the glycoprotein, of the pharmaceutical composition according to the present invention is a publicly known substance, and as has been disclosed in Japanese Patent publications Nos. 17149/1971, 36322/1976, 14274/1981, 14276/1981 and 39288/1981, the glycoprotein is obtained by culturing a basidiomycetous fungal species belonging to the genus Coriolus, extracting the thus proliferated mycelia or fruit bodies with hot water or an aqueous alkali solution, and removing low molecular weight substances having a molecular weight of less than 5000 and the thus obtained substance as an extract contains from about 18 to 38% by weight of proteins and shows a molecular weight of from 5,000 to 300,000 as determined by ultracentrifugal method.
The glycoprotein derived from the mycelia of Coriolus versicolor (Fr.) Quel. is liver brown in color and has a nitrogen content of 2 to 8%, in many cases 3 to 6%. Various color reaction tests on the glycoprotein according to the present invention gave the results as shown below.
______________________________________naphthol sulfuric acid reaction Purple(Molish's reaction)Indole sulfuric acid reaction Brown(Dische's reaction)Anthrone sulfuric acid reaction Greenish bluePhenol sulfuric acid reaction BrownTryptophane sulfuric acid reaction Purplish brownLowry-Folin process BlueNinhydrin reaction after hydrochloric Greenish blueacid hydrolysis______________________________________
The molecular weight of the glycoprotein according to the present invention is 5000 to 300,000 as measured according to an ultracentrifugal method. The glycoprotein according to the present invention contains about 18 to 38% by weight of proteins.
The saccharide moiety of the glycoprotein of the present invention consists mainly of β-D-glycan and the structure of the glycan moiety is a branched one containing 1→3, 1→4 and 1→6 bondings. Of the amino acids forming the protein moiety of the glycoprotein, the amount of acidic amino acids such as aspartic acid, glutamic acid, etc. and that of neutral amino acid such as valine, leucine, etc. are relatively large, and the amount of basic amino acids such as lysine, arginine, etc. is relatively small. The glycoprotein is soluble in water and almost insoluble in hexane, benzene, chloroform, methanol and pyridine. The glycoprotein slowly decomposes at a temperature around 120° C. when it is heated.
As will be seen in Table 1, the mammalian toxicity of the glycoprotein of the present invention is extremely low, and it hardly causes any side effects on animals. Namely, it is known to be a very safe substance to living bodies.
TABLE 1______________________________________Animal Route of LD.sub.50 (mg/kg)species administration Female Male______________________________________Mouse intravenous >1300 >1300Strain subcutaneous >5000 >5000ICR-JCL intraperitoneal >5000 >5000 oral >20000 >20000Rat intravenous >600 >600Strain subcutaneous >5000 >5000Donryu intraperitoneal >5000 >5000 oral >20000 >20000______________________________________
The mice used in the test for finding the above-mentioned acute toxicity value (LD 50 mg/kg) were of the strain ICR-JCL, 4 to 5 weeks after birth, and body weight of 21 to 24 g. The rats used in the same test were of the strain Donryu, 4 to 5 weeks after birth, and body weight of 100 to 150 g. The glycoprotein was dissolved in a physiological saline and administered via each route shown in Table 1. After administration, observation on the general symptoms, mortality and body weight of each of the thus treated animals were carried out for 7 days, and then they were sacrificed to be subjected to autopsy.
As are shown in Table 1, no case of death was found both on the mice and the rats even at the maximum dosage which could be given and accordingly, the glycoprotein of the present invention is extremely safe for living body to the extent that the value of LD 50 could not be actually determined.
As a result of examining the physiological and pharmaceutical properties of the glycoprotein derived from a basidiomycetous fungus belonging to the genus Coriolus, it has been found out that the glycoprotein shows antirheumatic activity, antithrombotic activity, analgetic activity, antipyretic activity, anti-hyperlipemic activity and anti-inflammatory activity and activities of reducing the level of blood sugar, raising the coronary blood flow, improving the capability of deformation of erythrocytes, reducing the blood pressure, ameliorating proteinuria and proteinemia and regulating production or metabolism of prostaglandins in a mammal, as well as the anti-tumour activity, and based on the findings, the present inventors have attained the present invention.
SUMMARY OF THE INVENTION
In the first aspect of the present invention, there is provided a pharmaceutical composition having antirheumatic activity, antithrombotic activity, analgetic activity, antipyretic activity, anti-hyperlipemic activity and anti-inflammatory activity and activities of reducing the level of blood sugar, raising the coronary blood flow, improving the capability of deformation of erythrocytes, reducing the blood pressure, ameliorating proteinuria and proteinemia and regulating production or metabolism of prostaglandins in a mammal in dosage unit form, which comprises a dosage effective to produce said activities of a glycoprotein having a molecular weight of 5000 to 300,000 as determined by ultracentrifugal method and about 18 to 38% by weight of proteins, produced by culturing a basidiomycetous fungal species belonging to the genus Coriolus, extracting the thus proliferated mycelia or fruit bodies with hot water or aqueous alkali solution and removing low molecular weight substances having a molecular weight of less than 5000 from the extract.
In the second aspect of the present invention, there is provided a method for the treatment of diabetes mellitus, rheumatism, ischemic heart diseases, ischemic cerebral diseases, hypertension, thrombosis, pains due to the accentuation of central nerve, pyrexia due to accentuation of central nerve, hyperlipemia, inflammatory diseases and nephrotic syndrome, which comprises administering to a mammal suffering from diabetes mellitus, rheumatism, ischemic heart diseases, ischemic cerebral diseases, hypertension, thrombosis, pains due to the accentuation of central nerve, pyrexia due to accentuation of central nerve, hyperlipemia, inflammatory diseases and nephrotic syndrome an effective amount of a glycoprotein having a molecular weight of 5000 to 300,000 as determined by ultracentrifugal method and about 18 to 38% by weight of proteins, produced by culturing a basidiomycetous fungal species belonging to the genus Coriolus, extracting the thus proliferated mycelia or fruit bodies with hot water or aqueous alkali solution and removing low molecular weight substances having a molecular weight of less than 5000 from the extract.
In the third aspect of the present invention, there is provided a method for regulating the production and metabolism of prostaglandins in a mammal, which comprises administering an effective amount of a glycoprotein having a molecular weight of 5000 to 300,000 as determined by ultracentrifugal method and about 18 to 38% by weight of proteins, produced by culturing a basidiomycetous fungal species belonging to the genus Coriolus, extracting the thus proliferated mycelia or fruit bodies with hot water or aqueous alkali solution and removing low molecular weight substances having a molecular weight of less than 5000 from the extract.
BRIEF EXPLANATION OF DRAWINGS
Of the attached drawings,
FIG. 1 shows the transition of the level of glucose in the blood of the rat experimentally made to be in a morbid state of showing a high level of sugar both in the urine and the blood, with the lapse of time.
FIG. 2 is a chart showing the transition of the blood pressure of SHR (spontaneous hypertensive rats) after administration of the glycoprotein of the present invention.
FIGS. 3 (a to d) shows the transition of each lipid in the blood of the patient of hyperlipemia to whom the glycoprotein according to the present invention was administered.
FIG. 4 is a graph showing the influence of the glycoprotein according to the present invention on the LDL-receptor of human fibroblasts.
FIG. 5 shows the transition of the amount of protein in the daily urine of the Donryu rat which had been made to show nephrosis-like symptoms by the administration of AN with the lapse of time, and also the transition of the amount of protein in the daily urine of the Donryu rat which had been administered preliminarily with the glycoprotein of the present invention and then AN was administered with the lapse of time.
FIG. 6 shows the transition of the amount of protein in the urine of a patient of lupus nephritis before and during the administration of the glycoprotein according to the present invention to the patient, with the lapse of time.
FIG. 7 shows the transition of the amount of protein in the urine of the patient of diabetic nephropathy with the lapse of time before and during the administration of the glycoprotein of the present invention.
FIGS. 8 and 9 are the diagrams showing the activity of the glycoprotein of the present invention in regulating PGE and PGF 2 α in the cultured media as the results of experiments in Example 21.
DETAILED DESCRIPTION OF THE INVENTION
The glycoprotein according to the present invention shows antirheumatic activity, antithrombotic activity, analgetic activity, antipyretic activity, anti-hyperlipemic activity and anti-inflammatory activity and activities of reducing the level of blood sugar, raising the coronary blood flow, improving the capability of deformation of erythrocytes, reducing the blood pressure, ameliorating proteinuria and proteinemia and regulating production or metabolism of prostaglandins in a mammal. The glycoprotein according to the present invention is used for the treatment of diabetes mellitus, rheumatism, ischemic heart diseases, ischemic cerebral diseases, hypertension, thrombosis, pains due to the accentuation of central nerve, pyrexia due to accentuation of central nerve, hyperlipemia, inflammatory diseases and nephrotic syndrome, and for regulating the production and metabolism of prostaglandins.
The followings are the pharmacological properties of the glycoprotein according to the present invention.
(1) Activity of reducing the level of blood sugar
The glycoprotein according to the present invention was orally administered at a dose rate of 30 to 300 mg/kg to the rat artificially made to diabetes mellitus by administration of streptozocin. As a result, the reduction of the level of blood sugar by 50 to 100 mg/dl was observed.
(2) Antirheumatic activity
In the case where the glycoprotein according to the present invention was administered to a patient suffering from rheumatism, improvements of both the pain and the grasping power were observed on the patient. In addition, in the animal experiment of rats, it was found that the glycoprotein had an anti-adjuvant arthritic activity. Namely, the glycoprotein of the present invention has an activity as an antirheumatic agent.
(3) Activity of raising the coronary blood flow
The glycoprotein according to the present invention shows an activity of raising the coronary blood flow and accordingly, the glycoprotein is useful as an improving agent of ischemic heart diseases. Namely, when the glycoprotein was injected into the upper artery of a cardiopulmonary specimen prepared from a normal beagle, an increase of the coronary blood flow was observed, and the effectiveness of the glycoprotein as an improving agent of ischemic heart diseases was shown.
The glycoprotein according to the present invention is effective as an agent for ameliorating ischemic heart diseases due to the activity of increasing the coronary blood flow. Namely, the pharmaceutical composition according to the present invention is effective in treating the several types of ischemic heart diseases such as coronary arteriosclerosis, acute- and chronic myocardial infarction, stable- or unstable angina pectoris, arrhythmia, heart failure, etc.
(4) Activity of improving the capability of deformation of erythrocytes
On the erythrocytes of the animal to which the glycoprotein according to the present invention was administered, the reduction of rate of hemolysis against the mechanical hemolytic action, in other words, the improvement of the capability of deformation of the erythrocytes was observed. The blood flow in the cerebral ischemic state was microcirculation, and since an activity of improving the capability of deformation of the erythrocytes was recognized in the glycoprotein according to the present invention, it was elucidated that the active ingredient, the glycoprotein, was able to facilitate the blood circulation. In addition, the glycoprotein is active in inhibiting the death of experimental animal due to thrombosis caused by arachidonic acid given to the animal.
The glycoprotein is useful as an agent for ameliorating ischemic cerebral diseases because of both the activity of improving the capability of deformation of erythrocytes and the activity of inhibiting the death due to thrombosis. The pharmaceutical composition for ameliorating ischemic cerebral diseases according to the present invention is effective in treating cerebral thrombosis or ischemic diseases accompanying the cerebral infarction due to arteriosclerosis.
(5) Activity of reducing the blood pressure
As a result of the experimental tests wherein the glycoprotein of the present invention was orally administered at dose rates in a range of from 30 to 300 mg/kg to SHR (spontaneous hypertensive rats), which were used broadly as the model of human essential hypertension, and their blood pressures were measured with the lapse of time by non-operative method, a reduction of the blood pressure was observed in a range of from 15 to 25 mmHg. Accordingly, the activity of the glycoprotein in reducing the blood pressure was recognized.
(6) Antithrombotic activity
The antithrombotic activity of the glycoprotein according to the present invention is explained as follows.
(i) Activity in inhibiting the aggregation of platelets
In the case where collagen, etc. which is present beneath the endotheliucomes to be exposed to blood flow due to arteriosclerosis and injury of the intima, the platelets adhere to the part and then, aggregation of the thus adhered platelets occurs. The aggregation of the platelets due to collagen causes the release of adenosine-diphosphoric acid(ADP), serotonin, etc. from the dense body of the thrombocyte. ADP has a strong activity of aggregating the platelets and accordingly, ADP causes an irreversible second aggregation.
As is seen in Example 10, an activity of inhibiting the aggregation of platelets is seen in the glycoprotein according to the present invention.
(ii) Activity in inhibiting the death due to thromboembolism
In the case where a platelets-aggregating substance such as ADP or water-soluble collagen is intravenously administered to a mouse, the platelets are aggregated in the blood flow to clog the capillary blood vessel resulting finally in pulmonary embolism, and the rat dies within 5 min.
In the case where the glycoprotein of the present invention was administered before the injection of the platelets-aggregating substance, an effect of inhibiting the death due to thromboembolism (refer to Example 11) was observed.
Namely, the glycoprotein according to the present invention is effective as an antithrombotic agent because of the activities of inhibiting the aggregation of platelets and of inhibiting the death due to aggregation of platelets.
(7) Analgetic and antipyretic activity
The analgetic- and antipyretic activity of the glycoprotein according to the present invention is explained as follows.
(i) Analgetic activity
As a result of examination on the analgetic activity of the glycoprotein as the active ingredient of the pharmaceutical composition of the present invention by the mechanical stimulation (by pressure) method and chemical stimulation method while using mice as the experimental animal, it was found that the oral administration of 1000 mg/kg of the glycoprotein caused the raise of the pressure at the time of exhibiting of the pseudo-escape reaction, the elongation of the time until the appearance of the pseudo-escape reaction and the reduction of writhing number.
(ii) Antipyretic activity
As a result of examination on the antipyretic activity of the glycoprotein as the active ingredient of the pharmaceutical composition of the present invention by the method of subcutaneous administration of beer yeast while using rats as the experimental animal, the oral administration of 1000 mg of the glycoprotein per kg body weight of the rat caused a pyrexia-suppressing effect, i.e., a reduction of body temperature to level of body temperature of the rat not treated with beer yeast.
(8) Anti-hyperlipemic activity
The anti-hyperlipemic activity of the glycoprotein according to the present invention will be explained as follows.
It has been known that the patient suffering from hyperlipemia also suffers from hypercholesterolemia and frequently is complicated by arteriosclerosis praecox. Accordingly, the treatment of hyperlipemia means not only the prevention and inhibition of arteriosclerosis but also the improvement thereof. Hitherto, the treatment of hyperlipemia is carried out for the purpose of repressing the synthesis of cholesterol, accelerating catabolism and excretion of cholesterol and repressing the absorption of cholesterol, and the anti-hyperlipemic pharmaceutical compositions now in use exhibit their activity via the above-mentioned functional mechanisms.
On the other hand, the glycoprotein according to the present invention reduces the high level of the lipids within blood via a novel functional mechanism.
Namely, in recent years, it has been found that the principal cause of hyperlipemia is the deficiency and the functional reduction of low density lipoprotein (hereinafter referred to as LDL)-receptor, and it has come to be considered that the amelioration of the acatastatic LDL receptor is the substantial and ideal treatment of hyperlipemia.
The pharmaceutical composition of the present invention is, in that sense, a new anti-hyperlipemic pharmaceutical composition which raise the level of LDL receptor in the patient's body, thereby reducing the lipids in the blood of the patient without causing side effect.
(9) Anti-inflammatory activity
The glycoprotein according to the present invention has an activity of repressing the edema due to carragheenin, that of repressing granuloma, and that of repressing adjuvant arthritis and accordingly, the pharmaceutical composition essentially containing the glycoprotein as an active component is useful as an anti-inflammatory agent.
These activities will be explained as follows.
(i) Activity of repressing the edema due to carragheenin
Following the method of Van Arman et al. (1963), the activity of repressing the occurrence of the edema due to carragheenin was examined on rats. The rate of repressing the occurrence of the carragheenin-edema was 50.6% when 1000 mg/kg of the glycoprotein was orally administered once to the rat (refer to Example 14).
(ii) Activity of repressing the occurrence of granuloma
Following the method of Winter et al. (1963), the activity of the present glycoprotein in repressing the granuloma was examined on rats. The rate of repressing granuloma due to cotton wool by the daily oral administration of 1000 mg/kg for 7 days of the glycoprotein was 49.9% (refer to Example 14).
(iii) Activity of repressing exudation
Following the method of Baris et al. (1965), the activity of the present glycoprotein in repressing exudation into the subcutaneously inserted pouch in the back of a rat containing air and croton oil was examined. Daily oral administration of 1000 mg/kg of the glycoprotein for 5 days inhibited the extravasation to the extent of 39.7%.
(iv) Activity of repressing the adjuvant-arthritis due to bacteria
Following the method of Fujiwara et al. (1971), the rate of repressing the occurrence of the adjuvant arthritis was examined by the daily oral administration of 1000 mg/kg of the glycoprotein for 7 days. The glycoprotein showed an activity of repressing arthritis in several months.
(10) Activity of ameliorating proteinuria and proteinemia
Since in the experimental case of rats exhibiting the nephrose-like symptoms and also in the clinical case of a patient suffering from lupus nephritis, administration of the glycoprotein according to the present invention caused the reduction of the level of proteins in the urine of the animal and the patient, it has been confirmed that the glycoprotein has an activity of ameliorating proteinuria and proteinemia and is useful as an active ingredient of the pharmaceutical composition for ameliorating nephrotic syndrome.
(11) Activity of regulating production or metabolism of prostaglandins
The glycoprotein according to the present invention participates the regulation of PGs such as PGA, PGB, PGC, PGD, PGE, PGF, PGG, PGH, PGI and the like, thromboxan A(TXA), thromboxan B(TXB) and the metabolites thereof, and in addition, the glycoprotein regulates not only one kind of PGs but also several kinds of PGs also in vitro. The activity of the glycoprotein in regulating the production of PGs and their metabolites is recognized by the following findings of the present inventors.
(i) The glycoprotein raised the level of cyclic adenosine monophosphate(c-AMP) which was closely related, as an intracellular messenger, to PGs (refer to Example 20).
(ii) As has been seen in the in vitro experiment on the metabolism of arachidonic acid taken into lymphocytes to some PGs (refer to Example 18), the glycoprotein participated the production of PGD 2 , PGE 2 , 6-keto-PGF 1 α and PGF 2 α.
(iii) The glycoprotein affected in vitro the biosynthesis of PGE and PGF 2 α in the cultured cancer cells (refer to Example 21).
(iv) As a result of administering the glycoprotein to cancer-bearing animals, the proliferation of the cancer was inhibited and the intra-cancer-cellular level of PGE was raised (refer to Example 22). In addition, the remarkably raised intraplasmic level of 6-keto-PGF 1 α in cancer-bearing animal was reduced to the normal level by the administration of the glycoprotein.
(v) The anti-arrhythmic act of the glycoprotein was inhibited by indomethacin which inhibited the metabolism of prostaglandin (refer to Example 25).
In the case where the pharmaceutical composition according to the present invention is administered for the treatment of diabetes mellitus, rheumatism, ischemic heart diseases, ischemic cerebral diseases, hypertension, thrombosis, pains due to the accentuation of central nerve, pyrexia due to accentuation of central nerve, hyperlipemia, inflammatory diseases and nephrotic syndrome, and for regulating the production and metabolism of prostaglandins in a mammal, the pharmaceutical composition according to the present invention may be used as the followings.
The pharmaceutical composition according to the present invention can be administered in combination with the other pharmaceutical composition for reducing the level of blood pressure such as those containing the conventionally-used active ingredient such as a derivative of sulfonylurea without reducing the activity of the active ingredient of the conventional pharmaceutical composition.
The pharmaceutical composition according to the present invention can be used in combination with the other antirheumatic agents such as a formulation of gold, chloroquine, penicillamine and the like.
By the combined use of the pharmaceutical composition according to the present invention with a coronary dilator such as amyl nitrite and nitroglycerol, etc. in the case of fits, or another coronary dilator, in the non-fit case, such as a formulation of nitrite, a formulation of xantine, papaverin, dipyridamole, prenylamine, benziodalon, carbocromene, efloxate, 2,6-pyridine-dimethanol-bis(N-methylcarbamate), berapamil, nicotinic acid, etc., and a sedative such as phenobarbital, meprobamate, chlorodiazepoxide, reserpine, chloropromazine, etc., a combined effect is expectable. In addition, the pharmaceutical composition according to the present invention may be used in combination with an anti-arteriosclerotic agent.
By the combined use of the pharmaceutical composition according to the present invention for ameliorating ischemic cerebral diseases with an agent for dilation of the cerebral blood vessels such as carbon dioxide, papaverine, buphenine, isoxsuprine, hexobendine, cyclandelate, ATP, ADP, adenosine phosphate, acetazolamide, pyritinol, raubasine, aqueous hypertonic solution of glucose, etc., a combined effect is expected. In addition, the pharmaceutical composition according to the present invention may be used in combination with an anti-arteriosclerotic agent.
In addition, the activity of the glycoprotein according to the present invention is not reduced even if the pharmaceutical composition according to the present invention is used in combination with a blocking agent broadly used as a hypotensive agent such as alkaloid, guanethidine, methyldopa and thiazide derivatives, and a combined effect is expectable.
Reinforcement of the effectiveness of the pharmaceutical composition according to the present invention is expectable by the combined use thereof with a conventional antithrombotic agent.
The combined use of the central nerve-repressing pharmaceutical composition according to the present invention with the other central nerve-repressing agent, for instance, a narcotic analgesic agent, a non-narcotic analgetic agent and an analgetic, anti-pyretic and anti-inflammatory agent such as those derived from salicylic acid, pyrazolone, indole, phenylacetic acid, anthranilic acid, thienopyridine, pyrimidine, pyrimidinylpyrazole, benzotriazine and benzothiazolinone exhibits the combined effect.
Since the active ingredient of the pharmaceutical composition according to the present invention shows an activity of reducing the levels of both cholesterol and β-lipoprotein in the blood and an activity of raising the level of LDL receptor, the pharmaceutical composition is useful as an antihyperlipemic pharmaceutical composition. Moreover, although the functional mechanism of the active ingredient of the pharmaceutical composition according to the present invention differs from those of the inhibitor of cholesterol-synthesis, the inhibitor of cholesterol-absorption and the eccritic of cholesterol which are now broadly used as the active ingredient respectively of the antihyperlipemic pharmaceutical composition, in the case where the glycoprotein according to the present invention is used in combination with each of the above-mentioned active ingredient of the other antihyperlipemic pharmaceutical compositions, the effect is higher than the sum of the effect of the active ingredient and the effect of the glycoprotein according to the present invention and accordingly, the combined use of the glycoprotein and the other active ingredient of each of the conventional antihyperlipemic pharmaceutical composition is an effective means for treating hyperlipemia.
The combined use of the glycoprotein according to the present invention with the other active ingredient of the conventional anti-inflammatory pharmaceutical composition, for instance, steroid formulations, non-steroid formulations and anti-inflammatory enzyme formulations exhibit a combined effect.
The glycoprotein according to the present invention may be used in combination with any other active ingredient of the conventional pharmaceutical compositions for ameliorating nephrotic syndrome, for instance, dexamethasone, betamethasone, prednisolone, indomethacin, dipyridamole and cyclophosphamide.
The administration of the pharmaceutical composition according to present invention may be carried out via one of several routes, and the glycoprotein according to the present invention may be used in combination with any one of the conventional prostaglandin-regulating pharmaceutical composition containing, as the active ingredient, aspirin, indomethacin, etc.
The glycoprotein according to the present invention may be administered orally or parenterally to human being, and preferably orally. Oral administration includes sublingual administration and parenteral administration includes subcutaneous injection, intramuscular injection, intravenous injection and instillation. The effective amount of administration of the glycoprotein depends on the species, the age, the individual difference and the morbid state of the object, however, in the cases of treating human patients, the daily dose rate is 10 to 1000 mg/kg preferably 20 to 600 mg/kg of the body weight, which is divided evenly into 1 to 3 portions so as to be administered one to three times per day.
For the case of oral administration, the pharmaceutical composition according to the present invention may take the solid form taken as it is such as tablet, granule, powder and capsule, the liquid form taken as it is such as solutions, suspensions, emulsions and syrups, mixtures taken after shaking or a solid form taken after dissolving in sterilized water not containing any pyretic substance. The pharmaceutical composition taken as a solid may contain the conventional additives such as binders, vehicles, lubricants, disintegrators, wettable agents, and the pharmaceutical composition taken as a liquid, may contain the conventionally used additives and preservatives. For the case of injection, the pharmaceutical composition may contain the other additives such as stabilizers, buffering agents, preservatives and isotonic agents and the product is supplied after filling in a dosage unit ampule or in a conventional container.
The present invention is explained in more detail in the following Examples; however, it should be recognized that the scope of the present invention is not restricted to these Examples.
EXAMPLE 1
Preparation of the glycoprotein of the present invention
Into 4 litres of an aqueous 0.1 N sodium hydroxide solution, 200 g of dried mycelia of Coriolus versicolor (Fr.) Quel. (FERM-P No. 2414(ATCC 20547)] of a moisture content of 8.8% and a gross nitrogen content of 2.5% were added, and the mycelia were extracted under agitation at a temperature of 90° to 95° C. for one hour, and then the mixture was cooled to below 50° C. and after adjusting the pH of the thus cooled mixture to 7.0 by aqueous 1N hydrochloric acid solution, the solid matter was removed from the mixture by suction filtration and the thus removed solid matter was washed with 500 ml of water. The mixture of the filtrate and the washings, amounting to 4.2 litres, was subjected to ultrafiltration by the use of a desk-top ultrafilter made by Amicon Inc. (provided with the ultrafiltration membrane: PM-5) under agitation and cooling under the operating pressure of 1.5 kg/cm 2 at 10° C., thereby removing low molecular weight substances of molecular weight of lower than 5,000, followed by concentration to obtain 300 ml of the processed aqueous extract. The aqueous extract was further subjected to freeze-drying to obtain about 26.6 g of a powdery substance liver brown in color in a yield of 13% of the mycelia. The thus obtained powdery substance had a moisture content of 7.5% and showed an elementary analytical composition of 40.5% of carbon, 6.2 of hydrogen, 5.8% of nitrogen and the balance of oxygen. The powdery substance was easily soluble in water.
The powdery substance showed an activity of inhibiting the proliferation of the transplanted sarcoma 180 as high as 90% when intraperitoneally injected to the transplanted mice and as high as 65% when orally administered to the transplanted mice.
EXAMPLE 2
Antidiabetic activity
Among a number of Wistar rat to which streptozocin had been intraperitoneally administered at a rate of 60 mg/kg, those in which glucosuria and positivity of blood sugar had been confirmed after about one week of the administration were administered with regular insulin. Among the thus treated animals, those once showed the reduction of the level of sugar both in urine and blood and in which high level of both glucosuria and blood sugar was confirmed after a few days of the administration of regular insulin were chosen as the model animals of diabetes mellitus for the following experiment:
After dissolving the glycoprotein of the present invention into distilled water, the aqueous solution was orally administered to each of the model animals at a dose rate of 30 or 300 mg/kg.
After 3, 6, 9 and 24 hours of the administration, blood specimen was taken from the caudal vein of each animal, and the content of glucose in the specimen was measured by enzymatic method while using RaBA kit, the results being shown in FIG. 1.
As are seen in FIG. 1, the administration of the glycoprotein of the present invention caused the reduction of glucose level in the blood of the thus treated rat, thereby verifying the effectiveness of the glycoprotein as a blood sugar-reducing agent.
In consideration of the above-mentioned toxicological property and the thus manifested pharmacological property of the glycoprotein of the present invention, it will be understood that the glycoprotein of the present invention can be put to practical use.
EXAMPLE 3
Anti-adjuvant arthritic activity
Among the rats to which a suspension of Mycobacterium tuberculosis in liquid paraffin had been injected subcutaneously into the pad of the right hind leg while following the method of Fujiwara et al. (1971), those showing the same extent of swelling of the hind leg after 14 days of the injection were chosen as the test animals and divided into two groups each consisting of 10 animals. To each animal of the first group, the glycoprotein of the present invention was orally administered at a daily dose rate of 1000 mg/kg every day for 7 days from the 15th day of injection. Then, the volume of the hind leg of each of the thus treated animals and that of each of the second group (not administered with the glycoprotein) were measured, and the antiarthritic activity of the glycoprotein was obtained by calculation according to the following formula:
Antiarthritic activity (I.R.)(%)=(1-T/C)×100
wherein:
T: means volume of the hind leg of the animal of the first group administered with the glycoprotein
C: means volume of the hind leg of the control animal of the second group to which the glycoprotein had not been administered.
As a result, the glycoprotein of the present invention showed a remarkable anti-adjuvant-arthritic activity of 35.9%.
EXAMPLE 4
Anti-chronic arthritic activity in a woman
To a woman of 62 in age who was suffering for 25 years from a disease diagnosed to be chronic arthritis of Classical, Stage of IV and Class 3, the glycoprotein of the present invention was administered every day for about 30 days at a daily dose of 3 g. As a result, the reduction of both the pain and the number of active joints of the patient was observed as will be seen in the following Table 2, and the patient's impression was highly improved to show the effectiveness of the glycoprotein of the present invention.
TABLE 2______________________________________ Before administra- After administra-Item tion tion for 30 days______________________________________Stiffness of joints felt in 10 10morningExtent of pain 1.5 0.5Grasping power -- 82/100 (left/right)Erythrocyte sedimentation 47 54valueCRT ± ±Number of active joint 4 1Impression of patient -- very goodJudgement of the physician -- improved______________________________________
EXAMPLE 5
Anti-chronic arthritic activity
As a result of the administration of the glycoprotein of the present invention at a daily dosage of 3 g for 6 months in combination with the administration of 6 tablets of Brufen® and 2 tablets of Indacin suppository both of which had been administered to a woman of 47 in age suffering for 4 years from chronic arthritis diagnosed to be Classical, Stage of III and of Class 2, a remarkable effect of improvement was confirmed as follows:
______________________________________ Before administra- after 6 months'Item tion administration______________________________________Stiffness felt in morning 60 0Extent of pain 2 1Grasping power 90/60 93/138 (left/right)Number of active joint 5 5Impression of patient -- goodJudgement of the physician -- improved______________________________________
EXAMPLE 6
Activity of increasing coronary blood flow
After preparing a cardiopulmonary specimen while using a group consisting of three normal beagles, an aqueous solution of the glycoprotein of the present invention prepared by dissolving the glycoprotein in a physiological saline was injected to the specimen from the upper large vein at a rate of 1, 10 and 100 mg/kg, respectively. The coronary blood flow was measured by an electromagnetic flowmeter inserted into the coronary sinus from the right atrium while using Morawity's cannula. The results are shown in Table 3. As are seen in Table 3, the average coronary blood flow showed an increase after the administration of the glycoprotein as compared to before the administration.
TABLE 3______________________________________Activity of increasing the coronary blood flowAmount of Glycoprotein Rate of increase of blood as comparedinjected (mg/kg) to the flow before injection (%)______________________________________ 1 21.0 10 35.2100 37.5______________________________________
EXAMPLE 7
Activity of improving the capability of deformation of the erythrocyte
The glycoprotein of the present invention was administered to each of six groups of Wistar rats, each group being consisted of five animals, at the dose rate of 10-10,000 mg/kg, by oral and intraperitoneal administration, respectively. After 3 hours of the administration, blood was taken from each rat, and added to 10 times by weight of physiological saline. After stirring the mixture in a mixer, thereby mechanically hemolysing the erythrocytes inthe mixture, the mixture was subjected to centrifugal separation. The amount of hemoglobin (A i ) in the thus obtained supernatant liquid was measured by colorimetry. The same procedures were carried out except for using distilled water in stead of the physiological saline to obtain the amount of hemoglobin (B i ) in the supernatant liquid, and the extent of hemolysis (H i ) was calculated by the following formula: ##EQU1##
The extent of hemolysis obtained from the blood of the control rat administered with distilled water instead of the glycoprotein of the present invention by the same procedures as above was calculated to be H c .
Relative rate of hemolysis was calculated by the following formula while using the mean value of H i and H c : ##EQU2##
The thus obtained results are shown in Table 4 after classifying into the route of administration and the dose rate.
As are seen in Table 4, the reduction of the relative rate of hemolysis was observed in the administered groups regardless of the route of administration of the glycoprotein. Namely, administration of the glycoprotein of the present invention caused the improvement of the capability of the erythrocytes in deformation.
TABLE 4______________________________________Activity of reducing the relative extent of hemolysisAmount of glycoprotein Route of Mean relative extent ofadministered (mg/kg) administration hemolysis (%)______________________________________10 i.p. 81100 i.p. 741000 i.p. 720 (control) i.p. 100100 p.o. 881000 p.o. 7910000 p.o. 750 (control) p.o. 100______________________________________
EXAMPLE 8
Activity of inhibiting the death due to thromboembolism
Following the method of Furlow et al, (refer to "Science" 187, 685, 1975), the glycoprotein was administered to each of ten rats of the two respective groups as follows:
First group: intraperitoneally at a dose rate of 100 mg/kg
Second group: orally at a dose rate of 1000 mg/kg
Control group: not administered with the glycoprotein
After 30 min of the administration, arachidonic acid was injected to each rat from the left carotid artery in the blood flow direction and the mortality of the rat was observed. The results are shown in Table 5.
TABLE 5______________________________________Activity of inhibiting thromboembolic deathDose rate Route of Number of rats of a group(mg/kg) administration Survived / Total______________________________________not adminis- -- 0/10tered 100 i.p. 6/101000 p.o. 6/10______________________________________
As are seen in Table 5, activity of the glycoprotein in inhibiting the death due to thromboembolism was recognized.
EXAMPLE 9
Hypotensive activity
After dissolving the glycoprotein of the present invention in distilled water, the thus obtained aqueous solution was orally administered to each of rats of spontaneous hypertension, and the blood pressure of the thus treated rats was measured with the lapse of time, the results being shown in FIG. 2.
As are seen in FIG. 2, it is understandable that the hypotensive activity of the glycoprotein is excellent.
Because of the close correspondence between the spontaneous hypertension in rats and the human essential hypertension, the pharmaceutical composition containing the glycoprotein of the present invention can be said effective as a hypotensor.
EXAMPLE 10
Activity in inhibiting aggregation of platelets
Human venous blood was collected into an aqueous citrate solution (as an anticoagulant) at a weight ratio of 9:1, and after subjecting the mixture (of blood and the solution) to centrifugal separation for 6 min at 400 G, the supernatant fluid was collected. From the thus obtained supernatant fluid, a platelet rich plasma (hereinafter referred to PRP) was prepared, and the residue of centrifugation was further subjected to centrifugal separation for 20 min at 700 G to obtain a supernatant fluid (hereinafter referred to the platelet poor plasma (hereinafter referred to as PPP).
(1) The case where the glycoprotein is not added
Each of the three coagulants, arachidonic acid at the concentration of 1.64 mM, collagen at the concentration of 0.26 mg/ml and adenosine-diphosphoric acid (ADP) at the concentration of 50 micro M was added to PRP, and transmissivity of aggregation, which was indicated by difference of transmission between PRP and PPP was measured by an agligometer (made by Biodata Co., model PAP-3). The value corresponds to to the extent of aggregation of platelets by each of the coagulants, and was referred to A 1 .sbsb.i.
(2) The case where the glycoprotein is added
The glycoprotein of the present invention was added to PRP and PPP, respectively at a rate of 1 mg/ml thereof, and after 2 min of the addition, each of the three coagulants was added to the thus treated PRP, and platelets aggregation were measured. In this case (2), the value corresponds to the extent of aggregation of platelets by each of the coagulants in the presence of the glycoprotein, and was referred to A 2 .sbsb.i.
The rate of inhibiting aggregation of platelets due to each of the coagulants by the glycoprotein (I.R. %) was obtained by the formula: ##EQU3##
The results are shown in Table 6:
TABLE 6______________________________________ Rate of inhibiting aggregation (%) due toSpecimen ADP Collagen Arachidonic acid______________________________________Platelets added with the 77 76 78glycoproteinControl (platelets without -- -- --adding the glycoprotein)______________________________________
As are seen in Table 6, the glycoprotein of the present invention showed the activity of inhibiting aggregation due to any one of the coagulants.
EXAMPLE 11
Inhibition of the death due to thromboembolism
The glycoprotein of the present invention was orally administered at a dose rate of 1 g/kg to each of the ten male ddY mice of body weight of 20 to 22 g, and after 3 hours of the administration, ADP at a rate of 400 mg/kg or soluble collagen (made by Sigma Co.) at a rate of 0.2 ml/kg was intravenously administered to each of the mice. Thereafter, the mortality of the group of mice was observed after 10 min of the administration of the coagulant. To each of the other ten male ddY mice, distilled water was orally administered instead of the glycoprotein according to the present invention while using them as control. The results are shown in Table 7.
As shown in Table 7, the glycoprotein of the present invention showed the activity of inhibiting the death due to thromboembolism by the coagulant.
TABLE 7______________________________________ Number of dead animal/Group total number of animalof mice ADP Collagen______________________________________Those administered with 4/10 4/10glycoproteinControl 10/10 10/10______________________________________
EXAMPLE 12
(1-1) Analgetic activity
Examination of analgetic activity by mechanical stimulation
Experimental animals were selected from female ICR mice by applying a pressure to the caudal base point while using a pressure stimulating apparatus of Takagi and Kameyama (made by Natsume Works.) and choosing the individuals showing the threshold value of pseudo-escaping in a range of 50 to 80 mmHg in pressure.
After dividing the thus selected animals into groups each consisting of 10 animals, the glycoprotein of the present invention was administered each animal of the first group orally at a dose rate of 1000 mg/kg and subjected to the apparatus. Thus, the pressure at the time when the animal showed a pseudo-escaping reaction and the time (sec) until the animal showed the pseudo-escaping reaction were determined, the pressure and the time being used for judging the analgetic effect. The results are shown in Table 8.
TABLE 8______________________________________ Pressure (mmHg) at Time (sec) the time when: until: pseudo-escaping reaction wasGroup shown (average)______________________________________Administered with the 75 35glycoproteinNot administered with 60 28glycoprotein (control)______________________________________
As are shown in Table 8, every animal administered with the glycoprotein of the present invention showed a higher value of the pressure and a longer time than control, thus confirming the analgetic activity of the glycoprotein of the present invention.
Examination of analgetic activity by chemical stimulation
After dividing 20 female ICR mice of 5 to 6 weeks after birth were divided in two groups each consisting of 10 animals, the glycoprotein of the present invention was orally administered to each of the mice of the first group at a dose rate of 1000 mg/kg, and after 30 min of the administration, an aqueous 0.6% solution of acetic acid was intraperitoneally injected into each of the thus treated mice. The number of writhing caused by the injection was counted by Kostet et al. method (1959) within 10 min after 10 min of the injection, and the rate of suppressing the writhing (%) due to the glycoprotein was calculated by the following formula:
Rate of suppressing (%)=(1-T/C)×100
wherein
T is the average number of writhing of the treated group
C is the average number of writhing of the group not administered with the glycoprotein.
The rate of suppressing the writhing by the glycoprotein was 52.1%, namely, the number of writhing being clearly reduced as compared to that in control. In other words, the glycoprotein of the present invention showed a significant analgetic activity.
(1-2) Antipyretic activity
Following the method of Winter et al. (1961), an aqueous 20% suspension of beer yeast was subcutaneously injected into each of six rats of a group, and after fasting the animals for 10 hours, the glycoprotein of the present invention was orally administered to each of the thus treated rats at a dose rate of 1000 mg/kg. Thereafter, the rectal temperature of each of the animals was measured with the lapse of time, thereby examining the antipyretic activity of the glycoprotein. The results are shown in Table 9 with the results on the control animals injected, however, not administered with the glycoprotein.
TABLE 9______________________________________Rectal temperature (average)after 2 hours of administration Rectal temperatureGroup (average) (°C.)______________________________________Not injected and not administered 37.0Injected but not administered 38.5Injected and administered 37.5______________________________________
As are seen in Table 9, the glycoprotein of the present invention showed an antipyretic activity. Namely, the temperature of the rats injected beer yeast and administered with the glycoprotein was kept at the level almost as the same as that of the rats not injected nor administered.
EXAMPLE 13
(1-1) Activity of reducing the level of lipids in the blood of the patients suffering from hyperlipemia
The glycoprotein of the present invention (hereinafter referred to as the glycoprotein) was orally administered continuously for about one month at a daily dosage of 3 g to 10 patients (3 men and 7 women) suffering from hyperlipemia. The levels of T-cholesterol, β-lipoprotein, high density lipoprotein (HDL), triglycerides (TG) before the administration were 293 to 405 mg/dl (mean 340 mg/dl), 418 to 1038 mg/dl (mean 741 mg/dl), 26.2 to 96.5 mg/dl (mean 49 mg/dl) and 73 to 425 mg/dl (mean 181 mg/dl), respectively in the blood of the patients. Although these patients had been administered with various anti-hyperlipemic pharmaceutical composition for at least 4 months, they were suffering from hyperlipemia, namely the cases to which the conventional anti-hyperlipemic pharmaceutical composition was ineffective.
Blood specimen was taken from each of the patients before beginning the administration of the glycoprotein of the present invention and during the administration two times, 14th and 28th day from the day of beginning the administration, and the lipid therein was examined, the results on the blood specimen taken on 28th day being shown in FIG. 3 (a to d). As are seen in FIG. 3, although the glycoprotein showed no effect on the values of HDL and TG, the levels of β-lipoprotein and T-cholesterol were significantly reduced. Particularly, the level of β-lipoprotein was reduced in all cases by 150 mg/dl in the average, the mean rate of reduction being 20%.
(1-2) Activity of ameliorating LDL-receptor in human fibroblast
Fibroblasts of a patient suffering from a hereditary disease, heterotype familiar hyperlipemia II a characterized by the hyperplasia of Achilles's tendon were used as an experimental material, and were subjected to subculture in MEM containing 20% fetal bovine serum following the modified method of Goldstein et al, fifth to tenth generation being handled.
After culturing the fibroblasts in a dish of 6 cm in diameter until they proliferated to a predetermined amount, 5% lipoprotein deficient serum and the glycoprotein at a concentration shown in FIG. 4 were added to the dish, and after further culturing for 48 hours, I 125 -labelled LDL was added to the dish, and after further culturing for 6 hours, the cells adhering to the dish were washed 6 times with phosphate buffer solution and cultured in a HEPES buffer solution added with sodium dextran sulfate for one hour.
The radioactivity of the liquid of the thus cultured fibroblasts was determined as the amount of the surface-binding LDL, i.e., the number of the receptor (N i ).
The same fibroblasts were cultured in the same manner as above except for adding the glycoprotein of the present invention, and the radioactivity of the liquid of the thus cultured fibroblasts was determined as above, the number of the receptor being N O .
The activity of raising the number of the surface bound I 125 -labelled LDL was represented by (N i /N O )×100 (%), and is shown in FIG. 4.
As are seen in FIG. 4, the surface-bound I 125 -LDL was increased by the addition of the glycoprotein, and it shows the increase of LDL-receptor.
EXAMPLE 14
(1-1) Activity of repressing edema due to carragheenin
Following the method of Van Armen et al. (1963), after one hour of forcible oral administration of the glycoprotein of the present invention to each of ten rats of the first group at a dose rate of 1000 mg/kg, an aqueous suspension of 1% carragheenin in a physiological saline was injected into the footpad of the right hind leg of the rat at a rate of 0.1 ml/animal. Thereafter, the volume of the right hind leg was determined with the lapse of time, and the rate of repressing the swelling of the leg (due to edema by carragheenin) was calculated according to the following formula:
Rate of repressing (%)=(1-T/C)×100
wherein
T is the volume (average) of the right hind leg of the rat administered with the glycoprotein and injected with carragheenin, and
C is that of the rat not administered with the glycoprotein and injected with carragheenin.
As a result, the glycoprotein showed a rate of repressing edema due to carragheenin as high as 50.6%, and it was found that the glycoprotein has an excellent anti-inflammatory activity.
(1-2) Activity of repressing granuloma
Following the method of Winter et al. (1963), two cotton wool pellets each weighing 30±1 mg were implanted subcutaneously into the back of each of 6 rats of the first group in the symmetrical positions to the median line, and the thus treated animals were administered orally with the glycoprotein of the present invention continuously for 7 days at a daily dosage of 1000 mg/kg. On the day after the last day of administration, the granuloma on the back of the rat was extirpated, dried and weighed.
The activity of the glycoprotein in repressing the granuloma was obtained by the same procedures as in (1-1).
As a result, the weight of the granuloma of every rat administered with the glycoprotein was smaller than that of every rat not administered with the glycoprotein. Namely, the glycoprotein of the present invention showed a average rate of repressing the granuloma due to cotton wool pellet of 49.9%.
(1-3) Activity of repressing exudation
Following the method of Baris et al. (1965), air was injected subcutaneously into the back of each of 6 rats of a group to form a pouch therein, and 0.5 ml of a 1% solution of croton oil in sesame oil was injected into the thus formed pouch. Thereafter, the glycoprotein as administered to the thus treated rats continuously for 5 days at a daily dosage of 1000 mg/kg. On the day after the last day of the administration, the volume of liquid exuded into the pouch was determined.
The rate of repressing the exudation was calculated as in (1-1). Namely, the glycoprotein of the present invention showed the average rate of repressing the exudation of 39.7%, the result showing the activity of the glycoprotein in repressing the exudation.
(1-4) Activity of repressing the aduvant-arthritis due to bacteria
Following the method of Fujiwara et al. (1971), a suspension of Mycobacterium tuberculosis in liquid paraffin was subcutaneously injected into the footpad of the right hind leg of each of a number of rats, and on the 14th day of the injection, twenty rats with the same volume of the right hind leg were selected from the thus treated rats. After dividing the thus chosen rats into two groups each consisting of 10 animals, the glycoprotein of the present invention was orally administered continuously for 7 days at a daily dose rate of 1000 mg/kg. Thereafter, the volume of the right hind leg of each of the thus treated ten animals, and that of the animals injected but not administered were determined to obtain the rate of repressing the swelling of the right hind leg due to adjuvant arthritis.
The glycoprotein showed the activity of repressing the occurrence of adjuvant arthritis of 35.9%.
EXAMPLE 15
Activity of ameliorating a nephrose-like morbid state
After preparing two groups of Donryu rats each weighing about 200 g, a group consisting of 5 animals, the glycoprotein of the present invention was administered to each of the rats in the first group continuously for 5 days at an oral, daily dose rate of 500 mg/kg and then aminonucleoside (hereinafter referred to AN) was subcutaneously injected as a solution in a physiological saline once a day for continuous 6 days at a daily dose rate of 15 mg/kg. AN has been known to cause proteinuria. To each of the rats of the second group, the glycoprotein was not administered but AN was administered in the same manner as in the first group.
Thereafter, the urine was collected every day from the thus treated rats of the two groups to examine the content of nitrogen in the urine specimens by Kjeldahl method, which was calculated to the content of protein therein.
The results are shown in FIG. 5. As will be seen in FIG. 5, the preliminary administration of the glycoprotein could repress the occurrence of proteinuria due to AN.
EXAMPLE 16
A case of treatment of lupus nephrosis
To a woman of 35 in age diagnosed to be lupus nephrosis, the glycoprotein of the present invention was orally administered continuously for more than one month at a daily dosage of 3 g in combination with the oral administration of prednisolone at a daily dosage shown in FIG. 6 for 10 days.
Her urine was daily collected to be analyzed for nitrogen therein, the value being transformed into the amount of protein in the daily urine. The results are shown in FIG. 6. As will be seen in FIG. 6, it was shown that the glycoprotein is active in ameliorating lupus nephrosis.
EXAMPLE 17
A case of treatment of diabetic nephropathy
To a woman of 45 in age diagnosed to be diabetic nephropathy, prednisolone and Endoxan® were orally administered as are shown in FIG. 7 and from the time shown in FIG. 7, the oral administration of the glycoprotein of the present invention was started at a daily dose of 3 g. Her urine wad daily collected to be analyzed for nitrogen therein, the data being calculated to the amount of protein in the urine and shown also in FIG. 7.
As will be seen in FIG. 7, it was shown that the glycoprotein of the present invention is effective in ameliorating diabetic nephropathy.
EXAMPLE 18
Effect of the glycoprotein on the metabolism of arachidonic acid (which has been taken into lymphocytes) into PGs in the lymphocyte
The lymphocytes were taken out from the spleen of a BALB/c mouse, and after suspending the lymphocytes in Eagle's MEM culture medium at a rate of 10 7 cells/ml, 2 μCi of 3 H-labelled arachidonic acid was added to the aqueous suspension and the mixture was incubated for 90 min at 37° C. After washing the thus incubated matter 3 times with Eagle's MEM culture medium, the cells were again brought into suspension in Eagle's MEM culture medium at a rate of 10 7 cells/ml. Thus prepared suspension was equally poured into six siliconed test tubes by 2 ml/test tube.
Into the first two test tubes, the glycoprotein of the present invention was added at a rate of 10 μg/ml, and into the second two tubes, the glycoprotein was added at a rate of 100 μg/ml and the third two tubes were used as control without adding the glycoprotein.
After incubating the thus prepared six test tubes for 60 min at 37° C., the test tubes were subjected to centrifugation for 5 min at 0° C. under 1200 r.p.m., and the thus obtained pellets of cultured cells from each two test tubes were put into a mixture of 2 ml of Eagle's MEM culture medium and 5 ml of petroleum ether, and after shaking the mixture and removing the petroleum ether layer, the thus remaining aqueous layer was adjusted to pH of 3.5 by addition of aqueous 0.5N hydrochloric acid solution.
The thus obtained acidic liquid was extracted 3 times with each 5 ml of ether, and after evaporating ether off from the ether extract, the dried solid was subjected to esterification by a diazomethane solution. The product of esterification was fractioned by thin layer chromatography while developing with a 90:50:20:100 by volume mixture of ethyl acetate, isooctane, acetic acid and water to obtained fractioned spots which were identified by the authentic specimens of PGD 2 , PGE 2 , PGF 2 α and 6-keto-PGF 1 α.
Each of the thus obtained, fractioned points was taken together with silica gel layer of the chromatographic column at the point and suspended in a liquid scintillation liquid, and then applied to a scintillation counter to obtain the count number due to 3 H bound to each of PGs, thereby obtaining the amount of each of PGs.
As a result, it was found that the amount of PGD 2 and the amount of PGE 2 formed in the two tubes containing 10 μg, and in the two tubes containing 100 μg of the glycoprotein were remarkably larger than those in the two tubes not containing the glycoprotein. The amount of PGF 2 α and the amount of 6-keto-PGF 1 α in the former were also larger than those in the latter, however, the difference between the groups was not so remarkable as in the former.
EXAMPLE 19
Effect of the glycoprotein on the production of PGs in the jejunum eviscerated from a rabbit
Pieces of the jejunum eviscerated from a female Japanese rabbit of about 2 kg in body weight were incubated in a Krebs' bicarbonate liquid placed in a reflux-incubator for 30 min under a flow of a 95:5 by volume mixture of gaseous oxygen and gaseous carbon dioxide at 37° C., and the amount of PGE present in the liquid culture medium was determined.
The same experiment was carried out, however, on the pieces of the jejunum eviscerated from another female Japanese rabbit to which the glycoprotein had been orally administered at a dose rate of 1 g/kg 2 hours before the operation.
It was found, as a result, that the amount of PGE was larger in the incubated liquid culture medium of the jejunum taken from the rabbit to which the glycoprotein had been administered than that in the first experiment on the rabbit not administered with the glycoprotein.
EXAMPLE 20
Effect of the glycoprotein on the level of c-AMP in the tumour cells of sarcoma 180
A mixture of 10 7 cells of the ascitogenous tumour taken from the abdomen of a sarcoma 180 cancer-bearing mouse, Eagle's MEM culture medium and the glycoprotein of the present invention in an amount of 100 g/ml of the Eagle's MEM culture medium was cultured for 5 min at room temperature. After ending the culture, the thus cultured medium containing the cells was boiled, homogenized and subjected to centrifugal separation. The level of c-AMP in the thus obtained supernatant liquid was determined by the method of Gilman.
The same procedures as above were carried out while without adding the glycoprotein of the present invention to find the level of c-AMP in the supernatant liquid as control.
As a result, the level of c-AMP in the case of adding the glycoprotein was 118 pmol/10 8 cells and on the other hand, the level of c-AMP in the case of not adding the glycoprotein was 89 pmol/10 8 cells.
The result shows that the glycoprotein of the present invention has an activity of raising the level of c-AMP in the tumour cells of sarcoma 180 ascitogenous tumour.
EXAMPLE 21
Effect of the glycoprotein on PGE and PGF 2 α in the cultured cancer cells
Into 10 ml of the culture medium prepared by adding 10% by volume of bovine fetal serum to Eagle's MEM culture medium, the glycoprotein of the present invention was added at a rate of 50 μg/ml, and after placing the thus prepared culture medium in a flask for tissue culture of 75 cm 2 in the base area (Code No. 25110, made by Corning Co. U.S.A), 5×10 5 cells of mononuclear cultured cell of human leukemia (Strain J-111) were inoculated, and cultured for 7 days at 37° C. under a flow of 95:5 by volume mixture of air and carbon dioxide, the culture medium having been exchanged with the new one on the 2nd and 4th day of culture.
After the culture was over, the finished culture medium was subjected to centrifugal separation at 4° C. under 1500 r.p.m. to obtain a supernatant liquid.
The respective contents of PGE and PGF 2 α in the thus obtained supernatant liquid were determined by the 3 H-Prostaglandin E radioimmunoassay kit and the 3 H-prostaglandin F radioimmunoassay kit (both kits made by Clinical Assay Co., U.S.A), respectively.
By comparing the thus obtained levels of the PGs to the levels obtained in the same experiment as above except for not adding the glycoprotein of the present invention, it was found, as are seen in FIGS. 8 and 9, that the addition of the glycoprotein in the culture medium caused the reduction of the levels of PGE and PGF 2 α in the finished culture medium.
EXAMPLE 22
Effect of the glycoprotein on the level of PGE in the cells of Ehrlich cancer
To each of female C57BL/6 mice in 8th week after birth, the cells of Ehrlich cancer were subcutaneously transplanted at a rate of 10 6 cells per animal, and after dividing the thus treated mice evenly into two groups, the glycoprotein of the present invention was orally administered every day from the second day of transplantation to each of the mice of the first group at a daily dose rate of 1 g/kg for 14 days without administering to the mice of the second group.
After 2 weeks of transplantation, all the mice were sacrificed by ether, and the tumours therein were eviscerated.
The tumour tissue obtained from each group of the mice were cut into minute pieces by scissors, and after placing the pieces in a glass-homogenizer, methanol was added at a rate of 7 ml per 1 g of the tumour tissue, and the mixture was homogenized at 0° C. After filtering the homogenate by a sheet of filter paper, the thus obtained filtrate was mixed well with 2 times by volume of chloroform, and the mixture was left to stand for 30 min at 4° C.
After removing the precipitated proteins in the mixture by filtration, the filtrate was dried to solid by a rotary evaporator, and after mixing the dried material with 2 ml of a mixture of chloroform, methanol and an aqueous diluted hydrochloric acid solution of pH of 2.0 in a separatory funnel to obtain a solution in which the dried material dissolved. Thereafter, the content of PGE in the thus obtained solution was determined by the 3 H-Prostaglandin E radioimmunoassay kit (refer to Example 21).
As a result, the content of PGE in the solution obtained from the mice to which the glycoprotein of the present invention had been administered was 4.7 ng/g tumour, and on the other hand, the content of PGE in the solution obtained from the mice not administered with the glycoprotein was 1.8 ng/g tumour.
Namely, the glycoprotein showed an activity of raising the level of PGE in the tumour cells.
EXAMPLE 23
Effect of the glycoprotein in preventing metastasis of transplanted cancer cells to the lung of mouse
Thirty female C3H/He mice in 8th week after birth were divided evenly into 3 groups, and after orally administering the glycoprotein of the present invention three times, namely 13, 7 and 1 hour before the under-mentioned transplantation to each mouse of the first group, the MH 134 hepatoma cells were at a rate of 2×106 cells/animal from the caudal vein of each of all the mice, and after 5, 11 and 17 hours of the transplantation, the glycoprotein of the present invention was orally administered to each mouse of the second group in the rate of 1 g/kg of body weight, those mice of the third group being not administered with the glycoprotein.
After two weeks of the transplantation, all the mice were sacrificed and the respective lungs were eviscerated, and the number of the cancerous lesion due to metastasis of the transplanted hepatoma cells and the number of the mice having metastatic lesion(s) were counted to find the rate of positivity of metastasis by calculating according to the following formula:
Rate of positivity of metastasis =(P/T)×100
wherein
P is the number of mice having metastatic lesion(s) and
T is the total number of mice in the group =10
As a result, in the first and second groups, the rate of positivity of metastasis was 60% and the average number of the metastatic lesion(s) was 2.1/animal, and in the third group, the positivity of metastasis was 100% and the average number of the metastatic lesion(s) was 4.5/animal.
Namely, the effectiveness of oral administration of the glycoprotein of the present invention in preventing the metastasis of transplanted cancer cells was confirmed.
EXAMPLE 24
Effect of the glycoprotein in regulating the level of 6-keto-PGF 1 α in the blood of spontaneous hypertensive rats to which sarcomatous cells were transplanted
To each of the rats suffering from spontaneous hypertension, 10 6 cells of the sarcoma induced by methyl-cholanthrene were subcutaneously transplanted in the back thereof, and the rats were evenly divided into two groups. To the rats of the first group, the glycoprotein of the present invention was orally administered every day for 13 days from after 24 hours of the transplantation at a daily dose rate of 1000 mg/kg while not administering thereof to the rats of the second group.
After two weeks of the transplantation, blood specimen was collected from the vena cava inferior of every one of the tumour-cell-transplanted rats.
The plasma of each blood specimen was extracted with ether, and after obtaining the lipid fraction by subjecting the plasma to thin layer chromatography, the lipid fraction was converted into a methyloxim-silyl derivative. The derivative was subjected to gas-chromatography and mass-spectrography to find the amount of 6-keto-PGF 1 α in the plasma.
As a result, the amount of 6-keto-PGF 1 α in the plasma of the rat transplanted with the sarcomatous cells and administered with the glycoprotein was on the average 4.4 ng/ml plasma and on the other hand, that in the plasma of the rat transplanted with the sarcomatous cells and not administered with the glycoprotein was on the average 11.0 ng/ml of plasma. For reference, that of the plasma of the rat not transplanted nor administered was 3.0 ng/ml of plasma.
Namely, the orally administered glycoprotein of the present invention showed an activity of maintaining the plasmic level of 6-keto-PGF 1 α of the rat transplanted with the methyl-cholanthrene-induced sarcomatous cells nearly at the same as that of the normal and intact rats.
EXAMPLE 25
Anti-arrhythmic activity of the glycoprotein
Female Wistar rats of about 200 g in body weight were evenly divided into four groups, and each rat of the first group was subjected to intravenous injection of an arrhythmia-inducing agent, aconitine, at 50 g/kg under anesthesia by urethane to cause the arrhythmic state in the rat. To each rat of the second group, the glycoprotein of the present invention was orally administered at a dose rate of 1000 mg/kg and after one hour of the administration, the same injection of aconitine was carried out. By comparing the electrocardiogram of the rat of the first group with that of the rat of the second group, it was found that the administered glycoprotein acted to improve the arrhythmic state.
In the next experiment, to each rat of the third and fourth groups, the same oral administration of the glycoprotein was carried out as in the second group, and then, indomethacin which is an inhibitor of metabolism of prostaglandins was administered intravenously in the rate of 10 mg/kg, resulting in disappearing of anti-arrhythmic activity of the glycoprotein according to the present invention.
Accordingly, the anti-arrhythmic effect of the glycoprotein according to the present invention is induced through prostaglandins.
EXAMPLE 26
Formulation of a pharmaceutical composition
Capsules each containing 330 mg of the glycoprotein of the present invention were prepared by filling the hard capsules #0 with the glycoprotein as it is while using an automatic filler under a pressure. | 4y
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BACKGROUND OF THE INVENTION
High cis-1,4-polybutadiene can be prepared by polymerizing 1,3-butadiene monomer with nickel based catalyst systems. Such nickel based catalyst systems contain (a) an organonickel compound, (b) an organoaluminum compound, and (c) a fluorine containing compound. Such nickel based catalyst systems and their use in the synthesis of high cis-1,4-polybutadiene is described in detail in U.S. Pat. No. 3,856,764, U.S. Pat. No. 3,910,869, and U.S. Pat. No. 3,962,375.
The high cis-1,4-polybutadiene prepared utilizing such nickel based catalyst systems typically has a high molecular weight. Due to this high molecular weight, the high cis-1,4-polybutadiene is generally oil extended. However, this precludes the high cis-1,4-polybutadiene from being utilized in many applications. For instance, such oil extended rubbers cannot be utilized in tire sidewalls which contain white sidewall compounds. In any case, there is a large demand for high cis-1,4-polybutadiene having a reduced molecular weight which can be processed without being oil extended.
Various compounds have been found to act as molecular weight reducing agents when used in conjunction with the nickel based catalyst system. For instance, Australian Patent 556,294 discloses that alpha-olefins, such as ethylene and propylene, act as molecular weight reducing agents when utilized in conjunction with such three component nickel catalyst systems. Canadian Patent 1,236,648 indicates that 1-butene, isobutylene, cis-2-butene, trans-2-butene, and allene act as molecular weight regulators when used in conjunction with such nickel based catalyst systems. U.S. Pat. No. 4,383,097 reveals that certain nonconjugated diolefins, such as 1,4-pentadiene, 1,6-heptadiene, and 1,5-hexadiene, act as molecular weight reducing agents when utilized in conjunction with such catalyst systems.
The processibility of high cis-1,4-polybutadiene rubbers can be improved by simply lowering their molecular weight. However, this approach also typically leads to increased cold flow. Accordingly, the use of conventional molecular weight reducing agents to improve rubber processibility leads to compromised cold flow characteristics.
SUMMARY OF THE INVENTION
It has been unexpectedly found that halogenated phenols act as molecular weight reducing agents when employed in conjunction with nickel based catalyst systems which contain (a) an organonickel compound, (b) an organoaluminum compound, and (c) a fluorine containing compound. It has further been discovered that halogenated phenols also act to increase the molecular weight distribution of high cis-1,4-polybutadiene rubbers prepared in their presence utilizing such nickel based catalyst systems. This means that halogenated phenols can be employed in conjunction with such nickel based catalyst systems to reduce the molecular weight of the rubber without sacrificing cold flow characteristics.
The subject invention more specifically discloses a process for producing high cis-1,4-polybutadiene having a reduced molecular weight and broad molecular weight distribution which comprises polymerizing 1,3-butadiene in the presence of (a) an organonickel compound, (b) an organoaluminum compound, (c) a fluorine containing compound, and (d) a halogenated phenol.
The present invention also reveals in the process for producing high cis-1,4-polybutadiene by polymerizing 1,3-butadiene monomer with a catalyst system containing (a) an organonickel compound, (b) an organoaluminum compound, and (c) a fluorine containing compound; the improvement which comprises conducting said process in the presence of a halogenated phenol which acts to reduce the molecular weight and to increase the molecular weight distribution of the high cis-1,4-polybutadiene.
DETAILED DESCRIPTION OF THE INVENTION
The polymerizations of this invention will typically be carried out as solution polymerizations in a hydrocarbon solvent which can be one or more aromatic, paraffinic, or cycloparaffinic compounds. These solvents will normally contain from 4 to about 10 carbon atoms per molecule and will be liquids under the conditions of the polymerization. Some representative examples of suitable organic solvents include isooctane, cyclohexane, normal hexane, benzene, toluene, xylene, ethylbenzene, and the like, alone or in admixture.
The halogenated phenols of this invention will also act as molecular weight reducing agents in bulk polymerizations which are carried out with nickel based catalyst systems containing (a) an organonickel compound, (b) an organoaluminum compound, and (c) a fluorine containing compound. Such bulk polymerizations are described in detail in British Patent 2,186,880. The teachings of British Patent 2,186,880 are incorporated herein by reference in their entirety.
In the solution polymerizations of this invention, there will normally be from about 5 to about 35 weight percent monomers in the polymerization medium. Such polymerization media are, of course, comprised of the organic solvent and the 1,3-butadiene monomer. As the polymerization proceeds, monomer is converted to polymer and accordingly the polymerization medium will contain from about 5 to about 35 weight percent unreacted monomers and polymer. In most cases, it will be preferred for the polymerization medium to contain from about 10 to about 30 weight percent monomers and polymers. It is generally more preferred for the polymerization medium to contain from 20 to 25 weight percent monomers and polymers.
Polymerization is typically started by simply adding the nickel based catalyst system and the halogenated phenol to the polymerization medium. Such polymerizations can be carried out utilizing batch, semi-continuous, or continuous techniques. In a continuous process additional 1,3-butadiene monomer, catalyst, halogenated phenol, and solvent are added to the reaction zone at the same rate as polymer, solvent, and residual reactants are removed from the reaction zone.
The halogenated phenols which are utilized in accordance with this invention have the structural formula: ##STR1## wherein R 1 , R 2 , R 3 , R 4 , and R 5 can be the same or different and represent hydrogen or a halogen, with the proviso that at least one member selected from the group consisting of R 1 , R 2 , R 3 , R 4 , and R 5 is a halogen. The halogen will typically be selected from the group consisting of fluorine, chlorine, bromine, and iodine. However, the halogen will typically be selected from the group consisting of fluorine, chlorine, and bromine. Some representative examples of halogenated phenols which can be employed include pentafluorophenol, pentachlorophenol, pentabromophenol, para-fluorophenol, para-chlorophenol, para-bromophenol, meta-fluorophenol, meta-chlorophenol, ortho-chlorophenol, ortho-bromophenol, ortho-fluorophenol, and meta-bromophenol. For economic and environmental reasons, para-chlorophenol is typically preferred.
The organoaluminum compound that can be utilized has the structural formula: ##STR2## in which R 1 is selected from the group consisting of alkyl groups (including cycloalkyl), aryl groups, alkaryl groups, arylalkyl groups, alkoxy groups, hydrogen and fluorine; R 2 and R 3 being selected from the group consisting of alkyl groups (including cycloalkyl), aryl groups, alkaryl groups, and arylalkyl groups. Some representative examples of organoaluminum compounds that can be utilized are diethyl aluminum hydride, di-n-propyl aluminum hydride, di-n-butyl aluminum hydride, diisobutyl aluminum hydride, diphenyl aluminum hydride, di-p-toly aluminum hydride, dibenzyl aluminum hydride, phenyl ethyl aluminum hydride, phenyl-n-propyl aluminum hydride, p-tolyl ethyl aluminum hydride, p-tolyl n-propyl aluminum hydride, p-tolyl isopropyl aluminum hydride, benzyl ethyl aluminum hydride, benzyl n-propyl aluminum hydride, and benzyl isopropyl aluminum hydride, diethylaluminum ethoxide, diisobutylaluminum ethoxide, dipropylaluminum methoxide, trimethyl aluminum, triethyl aluminum, tri-n-propyl aluminum, triisopropyl aluminum, tri-n-butyl aluminum, triisobutyl aluminum, tripentyl aluminum, trihexyl aluminum, tricyclohexyl aluminum, trioctyl aluminum, triphenyl aluminum, tri-p-tolyl aluminum, tribenzyl aluminum, ethyl diphenyl aluminum, ethyl di-p-tolyl aluminum, ethyl dibenzyl aluminum, diethyl phenyl aluminum, diethyl p-tolyl aluminum, diethyl benzyl aluminum and other triorganoaluminum compounds. The preferred organoaluminum compounds include triethyl aluminum (TEAL), tri-n-propyl aluminum, triisobutyl aluminum (TIBAL), trihexyl aluminum, diisobutyl aluminum hydride (DIBA-H), and diethyl aluminum fluoride.
The component of the catalyst which contains nickel can be any soluble organonickel compound. These soluble nickel compounds are normally compounds of nickel with a mono-dentate or bi-dentate organic ligands containing up to 20 carbon atoms. A ligand is an ion or molecule bound to and considered bonded to a metal atom or ion. Mono-dentate means having one position through which covalent or coordinate bonds with the metal may be formed. Bi-dentate means having two positions through which covalent or coordinate bonds with the metal may be formed. The term "soluble" refers to solubility in butadiene monomer and inert solvents.
Generally, any nickel salt or nickel containing organic acid containing from about 1 to 20 carbon atoms may be employed as the soluble nickel containing compound. Some representative examples of soluble nickel containing compounds include nickel benzoate, nickel acetate, nickel naphthenate, nickel octanoate, nickel neodecanoate, bis(α-furyl dioxime) nickel, nickel palmitate, nickel stearate, nickel acetylacetonate, nickel salicaldehyde, bis(cyclopentadiene) nickel, bis(salicylaldehyde) ethylene diimine nickel, cyclopentadienyl-nickel nitrosyl, bis(π-allyl nickel), bis(πcycloocta-1,5-diene), bis(π-allyl nickel trifluoroacetate), and nickel tetracarbonyl. The preferred component containing nickel is a nickel salt of a carboxylic acid or an organic complex compound of nickel. Nickel naphthenate, nickel octanoate, and nickel neodecanoate are highly preferred soluble nickel containing compounds. Nickel 2-ethylhexanoate, which is commonly referred to as nickel octanoate (NiOct) is the soluble nickel containing compound which is most commonly used due to economic factors.
The fluorine containing compound utilized in the catalyst system is generally hydrogen fluoride or boron trifluoride. If hydrogen fluoride is utilized, it can be in the gaseous or liquid state. It, of course, should be anhydrous and as pure as possible. The hydrogen fluoride can be dissolved in an inert solvent, and thus, can be handled and charged into the reaction zone as a liquid solution. Optionally, butadiene monomer can be utilized as the solvent. Inert solvents include alkyl-, alkaryl-, arylalkyl-, and aryl-hydrocarbons. For example, benzene and toluene are convenient solvents.
The boron trifluoride component of the catalyst can be gaseous boron trifluoride. It should also be anhydrous and as pure as possible.
The hydrogen fluoride and/or boron trifluoride can also be utilized as complexes in the catalyst system as the fluorine containing compound. Hydrogen fluoride complexes and boron trifluoride complexes can readily be made with compounds which contain an atom or radical which is capable of lending electrons to or sharing electrons with hydrogen fluoride or boron trifluoride. Compounds capable of such associating are ethers, alcohols, ketones, esters, nitriles and water.
The ketone subclass can be defined by the formula ##STR3## wherein R' and R are selected from the group consisting of alkyl radicals, cycloalkyl radicals, aryl radicals, alkaryl radicals, and arylalkyl radicals containing from 1 to about 30 carbon atoms; and wherein R' and R can be the same or different. These ketones represent a class of compounds which have a carbon atom attached by a double bond to oxygen. Some representative examples of ketones that are useful in the preparation of the ketone-hydrogen fluoride complexes or boron trifluoride complexes of this invention include dimethyl ketone, methylethyl ketone, dibutyl ketone, methyl isobutyl ketone, ethyl octyl ketone, 2,4-pentanedione, butyl cycloheptanone, acetophenone, amylphenyl ketone, butylphenyl ketone, benzophenone, phenyltolyl ketone, quinone and the like. The preferred ketones that can be used to form the ketone-hydrogen fluoride compounds and the ketone-boron trifluoride compounds of this invention are the dialkyl ketones of which acetone is most preferred.
The nitrile subclass can be represented by the formula RCN where R represents alkyl groups, cycloalkyl groups, aryl groups, alkaryl groups or arylalkyl groups that contain up to about 30 carbon atoms. The nitriles contain a carbon atom attached to a nitrogen atom by a triple bond. Representative but not exhaustive of the nitrile subclass are acetonitrile, butyronitrile, acrylonitrile, benzonitrile, tolunitrile, phenylacetonitrile, and the like. The preferred hydrogen fluoride-nitrile complex or boron trifluoride nitrile complex is the hydrogen fluoride benzonitrile complex or the boron trifluoride benzonitrile complex.
The alcohol subclass can be defined by the formula ROH where R represents alkyl radicals, cycloalkyl radicals, aryl radicals, alkaryl radicals, or arylalkyl radicals containing from about 1 to about 30 carbon atoms. These alcohols represent a class of compounds which have a carbon atom attached by a single bond to oxygen which is in turn attached to a hydrogen by a single bond. Representative but not exhaustive of the alcohols useful in the preparation of hydrogen fluoride complexes and boron trifluoride complexes are methanol, ethanol, n-propanol, isopropanol, phenol, benzyl alcohol, cyclohexanol, butanol, hexanol and pentanol. The preferred hydrogen fluoride-alcohol complex or boron trifluoride alcohol complex is hydrogen fluoride phenolate complex or boron trifluoride phenolate complex.
The ether subclass can be defined by the formula R'OR where R and R' represent alkyl radicals, cycloalkyl radicals, aryl radicals, alkaryl radicals, and arylalkyl radicals containing from about 1 to about 30 carbon atoms; wherein R and R' may be the same or dissimilar. The R may also be joined through a common carbon bond to form a cyclic ether with the ether oxygen being an integral part of the cyclic structure such as tetrahydrofuran, furan or dioxane. These ethers represent a class of compounds which have two carbon atoms attached by single bonds to an oxygen atom. Representative but not exhaustive of the ethers useful in the preparation of the hydrogen fluoride complexes or boron trifluoride complexes of this invention are dimethyl ether, diethyl ether, dibutyl ether, diamyl ether, diisopropyl ethers, tetrahydrofuran, anisole, diphenyl ether, ethyl methyl ether, dibenzyl ether and the like. The preferred hydrogen fluoride-ether complexes or boron trifluoride-ether complexes are hydrogen fluoride diethyl etherate, hydrogen fluoride dibutyl etherate, boron trifluoride diethyl etherate, boron trifluoride dibutyl etherate complexes.
The ester subclass can be defined by the formula ##STR4## wherein R and R' are selected from the group consisting of alkyl radicals, cycloalkyl radicals, aryl radicals, alkaryl radicals and arylalkyl radicals containing from 1 to about 20 carbon atoms. The esters contain a carbon atom attached by a double bond to an oxygen atom as indicated. Representative but not exhaustive of such esters are ethyl benzoate, amyl benzoate, phenyl acetate, phenyl benzoate and other esters conforming to the formula above. The preferred hydrogen fluoride-ester complex is hydrogen fluoride ethyl benzoate complex. The preferred boron trifluoride-ester complex is boron trifluoride ethyl benzoate complex.
Such complexes are usually prepared by simply bubbling gaseous boron trifluoride or hydrogen fluoride into appropriate amounts of the complexing agent, for instance, a ketone, an ether, an ester, an alcohol, or a nitrile. This should be done in the absence of moisture, and measures should be taken to keep the temperature from rising above about 100° F. (37.7° C.). In most cases, boron trifluoride and hydrogen fluoride complexes are prepared with the temperature being maintained at room temperature. Another possible method would be to dissolve the hydrogen fluoride or the complexing agent in a suitable solvent followed by adding the other component. Still another method of mixing would be to dissolve the complexing agent in a solvent and simply bubble gaseous hydrogen fluoride or boron trifluoride through the system until all of the complexing agent is reacted with the hydrogen fluoride or boron trifluoride. The concentrations can be determined by weight gain or chemical titration.
The three component catalyst system utilized can be preformed. If the catalyst system is preformed, it will maintain a high level of activity over a long period of time. The utilization of such a preformed catalyst system also results in the formation of a uniform polymeric product. Such preformed catalyst systems are prepared in the presence of one or more preforming agents selected from the group consisting of monoolefins, nonconjugated diolefins, conjugated diolefins, cyclic nonconjugated multiolefins, acetylenic hydrocarbons, triolefins, vinyl ethers and aromatic nitriles.
Some representative examples of olefins that can be used as the preforming agent in the preparation of stabilized catalysts are trans-2-butene, mixed cis- and trans-2-pentene, and cis-2-pentene. Some nonconjugated diolefins that can be used as preforming agents are cis-1,4-hexadiene, 1,5-heptadiene, 1,7-octadiene, and the like. Representative examples of cyclic nonconjugated multiolefins that can be used include 1,5-cyclooctadiene, 1,5,9-cyclododecatriene, and 4-vinyl cyclohexene-1. Some representative examples of acetylenic hydrocarbons which can be used as the preforming agent are methyl acetylene, ethyl acetylene, 2-butyne, 1-pentyne, 2-pentyne, 1-octyne, and phenyl acetyene. Triolefins that can be used as the preforming agent include 1,3,5-hexatriene, 1,3,5-heptatriene, 1,3,6-octatriene, 5-methyl-1,3,6-heptatriene and the like. Some representative examples of substituted conjugated diolefins that can be used include 1,4-diphenyl butadiene, myrcene (7-methyl-3-methylene-1,6-octadiene), and the like. Ethyl vinyl ether and isobutyl vinyl ether are representative examples of alkyl vinyl ethers that can be used as the preforming agent. A representative example of an aromatic nitrile that can be used is benzonitrile. Some representative examples of conjugated diolefins that can be used include 1,3-butadiene, isoprene, and 1,3-pentadiene. The preferred preforming agent is 1,3-butadiene.
A method of preparing the preformed catalyst so that it will be highly active and relatively chemically stable is to add the organoaluminum compound and the preforming agent to the solvent medium before they come into contact with the nickel compound. The nickel compound is then added to the solution and then the fluoride compound is added to the solution. As an alternative, the preforming agent and the nickel compound may be mixed, followed by the addition of the organoaluminum compound and then the fluoride compound. Other orders of addition may be used but they generally produce less satisfactory results.
The amount of preforming agent used to preform the catalyst may be within the range of about 0.001 to 3 percent of the total amount of monomer to be polymerized. Expressed as a mole ratio of preforming agent to nickel compound, the amount of preforming agent present during the preforming step can be within the range of about 1 to 3000 times the concentration of nickel. The preferred mole ratio of preforming agent to nickel is about 3:1 to 500:1.
These preformed catalysts have catalytic activity immediately after being prepared. However, it has been observed that a short aging period, for example 15 to 30 minutes, at a moderate temperature, for example 50° C.. increases the activity of the preformed catalyst greatly.
In order to properly stabilize the catalyst, the preforming agent must be present before the organoaluminum compound has an opportunity to react with either the nickel compound or the fluoride compound. If the catalyst system is preformed without the presence of at least a small amount of preforming agent, the chemical effect of the organoaluminum upon the nickel compound or the fluoride compound is such that the catalytic activity of the catalyst is greatly lessened and shortly thereafter rendered inactive. In the presence of at least a small amount of preforming agent, the catalytic or shelf life of the catalyst is greatly improved over the system without any preforming agent present.
The three component nickel catalyst system can also be premixed. Such premixed catalyst systems are prepared in the presence of one or more polymeric catalyst stabilizers. The polymeric catalyst stabilizer can be in the form of a monomer, a liquid polymer, a polymer cement, or a polymer solution. Polymeric catalyst stabilizers are generally homopolymers of conjugated dienes or copolymers of conjugated dienes with styrenes and methyl substituted styrenes. The diene monomers used in the preparation of polymeric catalyst stabilizers normally contain from 4 to about 12 carbon atoms. Some representative examples of conjugated diene monomers that can be utilized in making such polymeric catalyst stabilizers include isoprene, 1,3-butadiene, piperylene, 1,3-hexadiene, 1,3-heptadiene, 1,3-octadiene, 2,4-hexadiene, 2,4-heptadiene, 2,4-octadiene and 1,3-nonadiene. Also included are 2,3-dimethylbutadiene, 2,3-dimethyl-1,3-hexadiene, 2,3-dimethyl-1,3-heptadiene, 2,3-dimethyl-1,3-octadiene and 2,3-dimethyl-1,3-nonadiene and mixtures thereof.
Some representative examples of polymeric catalyst stabilizers include polyisoprene, polybutadiene, polypiperylene, copolymers of butadiene and styrene, copolymers of butadiene and α-methylstyrene, copolymers of isoprene and styrene, copolymers of isoprene and α-methylstyrene, copolymers of piperylene and styrene, copolymers of piperylene and α-methylstyrene, copolymers of 2,3-dimethyl-1,3-butadiene and styrene, copolymers of 2,3-dimethyl butadiene and α-methylstyrene, copolymers of butadiene and vinyltoluene, copolymers of 2,3-dimethyl-1,3-butadiene and vinyltoluene, copolymers of butadiene and β-methylstyrene, and copolymers of piperylene and β-methylstyrene.
In order to properly stabilize the catalyst system by this premixing technique, the polymeric catalyst stabilizer must be present before the organoaluminum compound has an opportunity to react with either the nickel compound or the fluorine containing compound. If the catalyst system is premixed without the presence of at least a small amount of polymeric catalyst stabilizer, the chemical effect of the organoaluminum compound upon the nickel compound or the fluoride compound is such that the catalytic activity of the catalyst system is greatly lessened and shortly thereafter rendered inactive. In the presence of at least a small amount of polymeric catalyst stabilizer, the catalytic or shelf life of the catalyst system is greatly improved over the same system without any polymeric catalyst stabilizer present.
One method of preparing this premixed catalyst system so that it will be highly active and relatively chemically stable is to add the organoaluminum compound to the polymer cement solution and mix thoroughly before the organoaluminum compound comes into contact with the nickel containing compound. The nickel compound is then added to the polymer cement solution. Alternatively, the nickel compound can be mixed with the polymer cement first, followed by the addition of the organoaluminum compound. Then the fluorine containing compound is added to the polymer cement solution. This is not intended to preclude other orders or methods of catalyst addition, but it is emphasized that the polymer stabilizer must be present before the organoaluminum compound has a chance to react with either the nickel containing compound or the fluorine containing compound.
The amount of polymeric catalyst stabilizer used to premix the catalyst system can be within the range of about 0.01 to 3 weight percent of the total amount monomer to be polymerized. Expressed as a weight ratio of polymeric catalyst stabilizer to nickel, the amount of polymeric catalyst stabilizer present during the premixing step can be within the range of about 2 to 2000 times the concentration of nickel. The preferred weight ratio of polymeric catalyst stabilizer to nickel is from about 4:1 to about 300:1. Even though such premixed catalyst systems show catalytic activity immediately after being prepared, it has been observed that a short aging period, for example 15 to 30 minutes, at moderate temperatures, for example 50° C., increases the activity of the preformed catalyst system.
A "modified in situ" technique can also be used in making the three component nickel catalyst system. In fact, the utilization of catalysts made by such "modified in situ" techniques results in more uniform control of the polymerization and the polymeric product. In such a "modified in situ" technique, the organoaluminum compound is added to neat 1,3-butadiene monomer with the nickel containing compound being added later. The butadiene monomer containing the organoaluminum compound and the nickel containing compound is then charged into the reaction zone being used for the polymerization with the fluorine containing compound being charged into the reaction zone separately. Normally, the organoaluminum compound and the nickel containing compound are charged into the reaction zone soon after being mixed into the butadiene monomer. In most cases, the organoaluminum compound and the nickel containing compound are charged into the reaction zone within 60 seconds after being mixed in the butadiene monomer. It will generally be desirable to utilize organoaluminum compounds and nickel containing compounds which have been dissolved in a suitable solvent.
The three component nickel catalyst systems utilized in the practice of the present invention have activity over a wide range of catalyst concentrations and catalyst component ratios. The three catalyst components interact to form the active catalyst system. As a result, the optimum concentration for any one component is very dependent upon the concentrations of each of the other two catalyst components. Furthermore, while polymerization will occur over a wide range of catalyst concentrations and ratios, the most desirable properties for the polymer being synthesized are obtained over a relatively narrow range. Polymerizations can be carried out utilizing a mole ratio of the organoaluminum compound to the nickel containing compound within the range of from about 0.3:1 to about 300:1; with the mole ratio of the fluorine containing compound to the organonickel containing compound ranging from about 0.5:1 to about 200:1 and with the mole ratio of the fluorine containing compound to the organoaluminum compound ranging from about 0.4:1 to about 10:1. The preferred mole ratios of the organoaluminum compound to the nickel containing compound ranges from about 2:1 to about 80:1. the preferred mole ratio of the fluorine containing compound to the nickel containing compound ranges from about 3:1 to about 100:1, and the preferred mole ratio of the fluorine containing compound to the organoaluminum compound ranges from about 0.7:1 to about 7:1. The concentration of the catalyst system utilized in the reaction zone depends upon factors such as purity, the reaction rate desired, the polymerization temperature utilized, the reactor design, and other factors.
The three component nickel catalyst system can be continuously charged into the reaction zone utilized in carrying out continuous solution polymerization at a rate sufficient to maintain the desired catalyst concentration. In continuous polymerizations, the halogenated phenol is continuously charged into the reaction zone at a rate sufficient to maintain the desired concentration of the halogenated phenol in the reaction zone. Even though the halogenated phenol is not consumed in the polymerization reaction, a certain amount of the halogenated phenol will need to be continuously added to compensate for losses. The total quantity of the 1,3-butadiene monomer, the catalyst system, the solvent and the halogenated phenol charged into the reaction zone per unit time is essentially the same as the quantity of high cis-1,4-polybutadiene cement withdrawn from the reaction zone within that unit of time. The three catalyst components can be charged into the reaction zone "in situ", or as has been previously described, as a preformed or premixed catalyst system. In order to facilitate charging the catalyst components into the reaction zone "in situ" they can be dissolved in a small amount of an inert organic solvent or butadiene monomer. Preformed and premixed catalyst systems will, of course, already be dissolved in a solvent.
The amount of halogenated phenol that needs to be employed as a molecular weight reducing agent varies with the type of halogenated phenol being employed, with the catalyst system, with the polymerization temperature, and with the desired molecular weight of the high cis-1,4-polybutadiene rubber being synthesized. For instance, if a high molecular weight rubber is desired, then a relatively small amount of halogenated phenol is required. On the other hand, in order to reduce molecular weights substantially, a relatively large amount of the halogenated phenol will need to be employed. Generally, greater amounts of the halogenated phenol are required when the catalyst system being utilized contains hydrogen fluoride or is an aged catalyst which contains boron trifluoride. Extremely effective halogenated phenols, such as pentafluorophenol, can be used in lower concentrations than less effective halogenated phenols and will nevertheless suppress molecular weights to the same degree.
As a general rule the molar ratio of the halogenated phenol to the organoaluminum compound will be within the range of about 0.01:1 to about 1:1. The molar ratio of the halogenated phenol to the organoaluminum compound will more typically be within the range of about 0.05:1 to about 0.8:1. In most cases desired molecular weights can be attained by employing a molar ratio of the halogenated phenol to the organoaluminum compound which is within the range of about 0.1:1 to about 0.6:1. Higher ratios of the halogenated phenol to the organoaluminum compound reduces molecular weights to a greater extent. However, larger ratios of the halogenated phenol to the organoaluminum compound also reduce yields. High yield can generally be attained with the molar ratio of the halogenated phenol to the organoaluminum compound is less than about 0.5:1. However, yields diminish substantially as the molar ratio of the halogenated phenol to the organoaluminum compound is increased above a ratio of about 0.6:1. For this reason, a molar ratio of the halogenated phenol to the organoaluminum compound of greater than about 0.8:1 will not normally be employed.
The temperatures utilized in the polymerizations of this invention are not critical and may vary from extremely low temperatures to very high temperatures. For instance, such polymerizations can be conducted at any temperature within the range of about -10° C. to about 120° C. The polymerizations of this invention will preferably be conducted at a temperature within the range of about 30° C. to about 90° C. It is normally preferred for the polymerization to be carried out at a temperature which is within the range of about 55° C. to about 75° C. Such polymerizations will normally be conducted for a period of time which is sufficient to attain a high yield which is normally in excess of about 80% and preferably in excess of about 90%.
The high cis-1,4-polybutadiene rubber made utilizing the techniques of this invention typically has a cis content in excess of about 95%. For example, the high cis-1,4-polybutadiene rubber made utilizing the techniques of this invention will typically have a cis content of about 97%, a trans content of about 2%, and a vinyl content of about 1%.
After the polymerization is completed, the high cis-1,4-polybutadiene rubber may be recovered from the resulting polymer solution (rubber cement) by any of several procedures. One such procedure comprises mixing the rubber cement with a polar coagulating agent, such as methanol, ethanol, isopropylalcohol, acetone, or the like. The coagulating agent can be added at room temperature or below whereupon the liquified low molecular weight hydrocarbons will vaporize. If desired, gentle heat may be applied to hasten the removal of low molecular weight hydrocarbons, but not sufficient heat to vaporize the polar coagulating agent. The vaporized low molecular weight hydrocarbon solvents can then be recovered and recycled. The coagulated rubber is recovered from the slurry of the polar coagulating agent by centrifugation, decantation or filtration.
Another procedure for recovering the high cis-1,4-polybutadiene rubber is by subjecting the rubber solution to spray drying. Such a procedure is particularly suitable for continuous operations and has the advantage that heat requirements are at a minimum. When such a procedure is used, the recovered polymer should be washed soon after recovery with a polar solvent in order to destroy the remaining active catalyst contained in the polymer. In such procedures the vaporized organic solvents are also easily recovered, but will normally require purification before being recycled.
The practice of this invention is further illustrated by the following examples which are intended to be representative rather than restrictive of the scope of the subject invention. Unless indicated otherwise, all parts and percentages are given by weight. Dilute solutions viscosities were determined in toluene at 30° C.
EXAMPLE 1-6
In this series of experiments pentafluorophenol was evaluated as a molecular weight reducing agent. In this series of experiments 500 grams of a 15% solution of 1,3-butadiene monomer in hexane was added to a series of quart (946 ml) polymerization bottles under a nitrogen atmosphere. The bottles were capped using a self-sealing gasket with a Teflon liner. Triisobutylaluminum was added with a hypodermic syringe followed by the addition of nickel octanoate. The molar ratio of the triisobutylaluminum to nickel octanoate was 40:1. After about 2 to 3 minutes the pentafluorophenol was added in the amount shown in Table I was added as a 0.12M solution. After allowing 2 or 3 minutes for the pentafluorophenol to react with the triisobutylaluminum, a hydrofluoric acid solution was added. A sufficient amount of hydrofluoric acid was added to attain a molar ratio of hydrofluoric acid to nickel octanoate of 100:1. The polymerization bottle was then placed in a constant temperature bath which was maintained at a temperature of 65° C. After a polymerization time of 1-2 hours, a short stop solution containing 1 phm (parts per hundred parts by weight of monomer) of rosin acid, 1 phm of 2,6-di-tertiary-butyl-para-cresol, which is also known as butylated hydroxy toluene (BHT), and 0.5 phm of triisopropanolamine was added. The polymer cement made was then hot air oven dried overnight.
The rubber samples which were recovered were evaluated to determine number average molecular weight, weight average molecular weight, and dilute solution viscosities. These results as well as yields and molecular weight distributions are reported in Table I.
TABLE I______________________________________ Cold DSV Flow (dl/ (mg/Ex PFP:Al Yield Mn Mw MWD g) min)______________________________________1 0 99% 163,000 703,000 4.3 3.83 0.262 0.12 97% 133,000 529,000 4.0 3.03 0.683 0.24 93% 80,000 457,000 5.8 2.44 1.454 0.36 87% 57,000 333,000 5.8 2.05 1.765 0.48 81% 38,000 293,000 7.7 1.83 3.186 0.60 73% 29,000 263,000 9.0 1.63 5.23______________________________________ PFP:Al = molar ratio of pentafluorophenol to triisobutylaluminum Mw = weight average molecular weight Mn = number average molecular weight Cold flow was measured at 50° C.
Inspection of the results presented in Table 1 show pentafluorophenol to be an extremely efficient molecular weight regulator. The number average molecular weight of the high cis-1,4-polybutadiene produced dropped sharply with increasing levels of pentafluorophenol, while the molecular weight distribution became broader. The molecular weight distribution of high cis-1,4-polybutadiene synthesized with conventional nickel based catalyst systems is typically within the range of about 4.3 to about 4.8. However, by utilizing the halogenated phenol as a molecular weight reducing agent the molecular weight distribution of the rubber produced could be increased to well over 4.8. in fact, in Examples 3 and 4 molecular weight distributions of greater than 5.0 were attained. In Examples 5 and 6 molecular weight distributions of greater than 7.0 and 9.0 were attained.
EXAMPLES 7-14
In this series of experiments para-fluorophenol was evaluated as a molecular weight reducing agent. The polymerizations were conducted in a series of four ounce (118 ml) polymerization bottles. The polymerization bottles were filled with 100 ml of a 13% solution of 1,3-butadiene monomer in hexane under a nitrogen atmosphere. Then triisobutylaluminum was added utilizing a hypodermic syringe followed by the addition of 0.02 phm of nickel octanoate. A sufficient amount of triisobutylaluminum was added to realize a molar ratio of triisobutylaluminum to nickel octanoate of 40:1. After 2-3 minutes, the para-fluorophenol was added as a 0.1M solution in hexane. After allowing another 2-3 minutes for the para-fluorophenol to react with the triisobutylaluminum, a solution of hydrofluoric acid was added. The molar ratio of hydrofluoric acid to nickel octanoate was 100:1. The polymerization bottles were then placed in a constant temperature bath which was maintained at 65° C. with the bottles being rotated end-over-end. The polymerization was allowed to proceed for 90 minutes. Then, the polymerization was short-stopped by the addition of 1.0 phm of rosin acid, 1.0 phm of BHT, and 0.5 phm of triisopropanolamine. The rubber cements prepared were subsequently dried overnight in a hot air oven. The molar ratio of para-fluorophenol to triisobutylaluminum, yield, and DSV is reported in Table II.
TABLE II______________________________________Example PFP:Al Yield DSV(dl/g)______________________________________ 7 0 92% 4.10 8 0.05 92% 3.92 9 0.10 91% 3.8010 0.15 94% 3.7811 0.20 92% 3.6812 0.25 90% 3.3113 0.50 87% 3.0314 1.00 6% ND______________________________________ PFP:Al = molar ratio of parafluorophenol to triisobutylaluminum DSV = dilute solution viscosity
As can be seen by inspecting Table II, parafluorophenol is not as efficient as pentafluorophenol. However, some of this difference may be attributable to temperature differences because the quart polymerization bottles probably run somewhat hotter.
EXAMPLES 15-19
In a preferred embodiment of this invention, the trialkylaluminum component of the catalyst system is preformed with the halogenated phenol. By preforming the organoaluminum component of the catalyst system with the halogenated phenol, higher conversions can typically be attained. Better reproducibility of conversions and Mooney viscosities is also realized when the catalyst is preformed. The preforming of the catalyst can be carried out by slowly adding a solution of the halogenated phenol to a solution of the organoaluminum compound. The preformed organoaluminum/halogenated phenol component of the catalyst system can then be further diluted with additional organic solvent to the desired concentration.
In this series of experiments, the triisobutylaluminum component of the catalyst system was preformed with para-chlorophenol. The molar ratio of the para-chlorophenol to the triisobutylalumimum is shown in Table III. In polymerizations where the triisobutylaluminum component is preformed with the halogenated phenol, it is typically desirable to reduce the level of hydrofluoric acid employed in the catalyst. As a rule of thumb, the amount of hydrofluoric acid employed is reduced by one mole for every mole of para-chlorophenol employed.
These polymerizations were conducted in a series of quart (946 ml) polymerization bottles under a nitrogen atmosphere. The polymerization bottles were filled with 500 ml of 16.1% solutions of 1,3-butadiene monomer in hexane. The polymerization bottles were capped using a self-sealing gasket with a Teflon liner. The preformed triisobutylaluminum/para-chlorophenol component was added with a hypodermic syringe followed by the addition of nickel octanoate and hydrofluoric acid. Nickel octanoate was employed in all the experiments in this series at a level of 0.01 phm. The molar ratio of the triisobutylaluminum to the nickel octanoate was 40:1. The ratio of hydrofluoric acid to the triisobutylaluminum is shown in Table III.
The polymerization bottles were placed in a constant temperature bath which was maintained at a temperature of 65° C. After a polymerization time of about 90 minutes, a short stop solution was added at such a level to give 1 phm (parts per hundred parts by weight of monomer) of rosin acid, 1 phm of 2,6-di-tertiary-butyl-para-cresol, which is also known as butylated hydroxy toluene (BHT), and 0.5 phm of triisopropanolamine was added. The polymer cement made was then hot air oven dried overnight.
The rubber samples which were recovered were evaluated to determine yields and Mooney ML1+4(100° C.) viscosities. As can be seen, the Mooney viscosities of the polymers made were reduced with increasing amounts of the para-chlorophenol modifier.
TABLE IV______________________________________Ex-ample p-CL--P:Al HF:Al Yield (%) ML1 + 4(100° C.)______________________________________15 0 2.50 93 7916 0.70 1.80 88 5417 0.80 1.70 80 5618 0.90 1.60 60 4619 1.00 1.50 54 36______________________________________ p-Cl--P:Al = molar ratio of parachlorophenol to triisobutylaluminum HF:Al = molar ratio of hydrofluoric acid to triisobutylaluminum
While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made without departing from the scope of the present invention. | 4y
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. patent application Ser. No. 10/909,626, now U.S. Pat. No. 7,259,641, filed on Feb. 28, 2005, entitled: “Microelectromechanical Slow-wave Phase Shifter Device and Method”. This application claims priority to provisional application entitled: “True Time Delay Phase Shifting Method and Apparatus with Slow-Wave Elements,” filed Feb. 27, 2004 by the present inventors and bearing application No. 60/521,146.
GOVERNMENT SUPPORT
This invention was developed under support from the National Science Foundation under grant/contract number ECS9875235; accordingly the U.S. government has certain rights in the invention.
BACKGROUND OF THE INVENTION
A true time delay (TTD) phase shifter is a component used in microwave and millimeter wave radar and communications systems to control the time delay imposed upon a signal along a particular signal path within a system. The most common use of TTD components is within phased array radars, where it is possible that thousands of TTD components may be necessary and would be connected to each antenna element within a large array of such elements. In such an example the TTD components would facilitate electronic steering of the transmit and/or receive direction of the antenna array. The most common implementation of TTD components using current technology is in the form of a monolithic microwave integrated circuit (MMIC), in which transistors are used to realize switches, and these switches are used to select among different sections of transmission lines of varying length, thus enabling a tuning of the time delay. In the past 3-4 years new implementations of TDD components have been developed based upon the use of radio frequency micro electro mechanical systems (RF MEMS).
Distributed micro electro-mechanical (MEM) transmission lines (DMTLs) are a proven solution for very high performance, low loss true time delay phase shifters. The DMTL, as known in the art, usually consists of a uniform length of high impedance coplanar waveguide (CPW) that is loaded by periodic placement of discrete MEM capacitors. The MEM devices are typically designed such that S11 for a DMTL section is less than −10 dB for the two phase states, i.e. with MEM capacitors in the up- and down-state positions. The increase in the distributed capacitance in the down-state provides a differential phase shift (Δφ) with respect to the phase in the upstate.
A limitation of the capacitively-loaded DMTL known in the prior art is that the amount of phase shift is proportional to the difference in the loaded and unloaded impedances, thus restricting the achievable Δφ per unit length in light of impedance matching considerations.
Today, a large phased array radar system can cost millions of dollars. This cost can be lowered by orders of magnitude through the use of MEMS technologies. Still, there is a physical limitation to the performance achievable with RF MEMS TTD devices that operate only on the change of the capacitive loading of a transmission line. As the capacitance changes, a property of the transmission line known as the characteristic impedance (Zo) changes along with the desired change in the propagation constant. As Zo changes, there is a mismatch that arises between the TTD device and the system in which it is integrated, causing power to be reflected from the TTD device input. This mismatch is often described in terms of a parameter known as return loss (RL). A generally accepted upper limit for RL is 10 dB. The physical limitation of the capacitive only TTD device is that the amount of time delay per unit length of transmission line that can be achieved is restricted by the need to keep RL>10 dB. As one attempts to achieve greater time delay, larger changes in Zo are inherently produced, thereby decreasing the RL.
What is needed in the art is a device that improves upon the capacitance-only TTD device architecture currently known in the art. Accordingly, a device that produces true time delay phase shifting in which large amounts of time delay can be achieved without significant variation in the effective characteristic impedance of the transmission line, and thus also the input/output return loss of the component, would solve the problem of the devices currently known in the art for use in the microwave and mm-wave industry.
SUMMARY OF INVENTION
The present invention provides a method and apparatus for RF MEMS TTD components in which RF MEMS tunable components are placed along the length of a transmission line. As the mechanical configuration of the MEMS devices is changed, through electro static actuation, the effective loading on the transmission line is changed, which in turn changes the propagation constant and the corresponding time to propagate along the transmission line.
In accordance with the present invention, a microelectromechanical slow-wave phase shifter device and method of use are provided including at least one center conductive element, at least two ground plane elements laterally located proximal to the center conductive element, the at least two ground plane elements having a slot formed within, at least one actuatable ground shorting beam and an actuatable shunt beam configured to control access to the slot formed in the at least two ground plane elements.
The actuatable ground shorting beam further includes a first two actuatable ground shorting beams having electrical connectivity to a first of the two laterally located ground plane elements, and a second two actuatable ground shorting beams having electrical connectivity to a second of the two laterally located ground plane elements and a ground shorting beam bias line to control actuation of the ground shorting beams. In a particular embodiment, the slot formed in the ground plane has entrance point and an exit point to the transmission. As such, a first of the two actuatable ground shorting beams controls access to the entrance point and a second of the two actuatable ground shorting beams controls access to the exit point of the slot.
The actuatable shunt beam is suspended over the center conductive element and electrically connects the two ground plane elements. A shunt beam bias line is used to control actuation of the shunt beam.
In a particular embodiment, the actuation of the shunt beam and the ground shorting beams are controlled by an electrostatic supplied through the appropriate bias line.
The slow-wave device of the present invention can be pre-fabricated and then integrated with a planar transmission line having a center conductor and two laterally located ground planes on either side of the center conductor. In this configuration, the center conductive element is electrically connected to the center conductor of the planar transmission line and each of the two ground plane elements are electrically connected to each of the two laterally located ground planes of the transmission line.
In an additional embodiment, a plurality of conductive slots may be formed to provide additional propagation delay and the ability to have a multi-bit system. With this configuration, at least two ground plane elements are laterally located proximal to the center conductive element, and the at least two ground plane elements include a plurality of conductive slots formed within and electrically isolated from each other. As such, a plurality of actuatable ground shorting beams and a plurality of actuatable shunt beams are configured to control access to the slots formed in the at least two ground plane elements. The plurality of actuatable ground shorting beams and the plurality of actuatable shunt beams may be addressed either individually or simultaneously. This configuration allows for a multi-bit phase shifter.
In a particular embodiment, the actuation of the plurality of actuatable ground shorting beams and the plurality of actuatable shunt beams is such that a multi-bit phase shifter for use as a tunable true-reflect-line calibration set is provided.
In comparison to the MMIC devices currently known in the art, the RF MEMS TTD components in accordance with the present invention provide better performance (lower loss) and significantly lower cost. The present invention improves upon the capacitance-only TTD device architecture by introducing cascaded, switchable slow-save CPW sections. Theoretically, the time delay can be increased to any value while maintaining a fixed value for Zo. As such, dramatic improvements upon the current state of the art (SOTA) have been demonstrated.
The present invention enables the production of a new class of TTD devices that offer higher performance, smaller size and lower cost. In accordance with the present invention a new true time delay MEM phase shifter topology is presented that overcomes the limitations of the capacitor-only DMTL. The topology uses cascaded, switchable slow-wave CPW sections to achieve high return loss in both states, a large Δφ per unit length, and phase shift per dB that is comparable to previously reported performance
In a particular embodiment, the slow-wave MEM device in accordance with the present invention achieved a greater than 20 dB return loss in both states with the maximum Δφ. Experimental results for a single, 460 micron long slow-wave unit-cell demonstrate RL greater than 22 dB through 50 GHz with Δφ˜41° at 50 GHz. A 4.6 mm-long phase shifter comprised of 10 slow-wave unit-cells provides a measured Δφ per dB of approximately 317°/dB (or 91°/mm) at 50 GHz with RL greater than 21 dB.
In an alternate design the slow wave structure was also loaded with discrete MEM capacitors. For this design, the measured Δφ per dB is 257°/dB at 50 GHz with RL greater than 19 dB. This topology provides an attractive alternative for increasing the phase shift per dB if the constraint on the return loss is reduced. In a particular embodiment, a reconfiguration MEMS-based transmission line is provided in which there is independent control of the propagation delay and the characteristic impedance. In accordance with this embodiment, separate control of inductive and capacitive MEMS slow-wave devices in accordance with the present invention are used either to maintain a constant LC product (constant Z o ) or a constant L/C ratio (constant β), while changing the ratio or product, respectively. This embodiment employs metal-air-metal capacitors at the input and output of each of the slow-wave sections.
Accordingly, the present invention provides a device and method that improves upon the capacitance-only TTD device architecture currently known in the art. The slow-wave device in accordance with the present invention produces true time delay phase shifting in which large amounts of time delay that are achieved without significant variation in the effective characteristic impedance of the transmission line, and thus also the input/output return loss of the component.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which:
FIG. 1 is an illustrative schematic of the slow wave structure in the Normal and Slow-wave states in accordance with the present invention.
FIG. 2 is an illustrative 3-dimensional view of the slow-wave unit cell in accordance with the present invention.
FIG. 3 is an illustrative view of the measured differential phase shift and S11 for the unit-cell in FIG. 1 . The return loss (RL) is equal to the negative of S11 in dB. The solid line for Δφ curve represents EM simulation data and the dashed lines represent measured data.
FIG. 4 is an illustrative view of a schematic of the phase shifter in accordance with the present invention. The phase shifter has 10 cascaded slow-wave unit-cells.
FIG. 5 is an illustrative view of the measured S11 and differential phase shift of the 10-section slow-wave phase shifter in accordance with the present invention. The solid line for Δφ curve represents EM simulation data and the dashed lines represent measured data. The return loss (RL) is equal to the negative of S11 in dB.
FIG. 6 is an illustrative view of the measured S21 (insertion gain) for both states of the 10-section phase shifter in accordance with the present invention. Solid lines represent EM simulation data and dashed lines represent measured data.
FIG. 7 is an illustrative view of the comparison of S11 and differential phase shift for both the states in accordance with the present invention. Solid lines represent EM simulation data and dashed lines represent measured data.
FIG. 8 is a table of exemplary characteristics of the slow-wave unit-cell in accordance with the present invention.
FIG. 9 is an illustrative view of a 4-bit MEM slow-wave phase shifter in accordance with the present invention.
FIG. 10 is an illustrative view of the S11 of the 4-bit slow-wave MEM phase shifter in the various states as identified, in accordance with the present invention.
FIG. 11 is an illustrative view of the comparison of S11 and the differential phase shift for the states of the 4-bit slow-wave MEM phase shifter in accordance with the present invention.
FIG. 12 is an illustrative view of a 1-bit phase shifter employing maximum phase shift by actuating the MAM capacitors in the delay state of the slow-wave sections.
FIG. 13 is an illustrative of the comparison of measured (dashed) and simulated (solid) S11 (dB) of a 7.4 mm-long tunable Z o -line with constant propagation constant in both states.
FIG. 14 is an illustrative flow diagram of a method of manufacturing of the slow-wave device in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention.
The differential phase shift between the up- and down-states of a DMTL with capacitive-loading is accompanied by a change in the effective characteristic impedance in each state. Using the quasi-TEM assumption, the relationship between phase shift for a DMTL of length L and characteristic impedance is derived as shown below in Equation 1. Assuming a reference impedance of 50□, Z up and Z dn need to be approximately 55Ω and 45.4Ω, respectively, in order to maintain RL greater than 20 dB. The resulting Δφ per unit length is 17.8°/mm at 50 GHz. Achieving this small variation in the impedance requires tight control over the value of the MEM capacitor in the up- and down-state positions.
Δϕ
=
(
ω
Z
0
ɛ
eff
c
)
·
(
1
Z
up
-
1
Z
dn
)
·
L
rad
(
1
)
The MEM slow-wave unit-cell 10 shown in FIG. 1 is designed to provide small variations in the impedances around 50Ω, with a Δφ per unit length that is comparable to (and greater than) a capacitively-loaded DMTL that has a worst-case RL near 10 dB. In an exemplary embodiment, the unit-cell is 460 cm long and consists of two beams 30 on each ground plane 20 and a shunt beam 35 that connects the ground planes 20 and is suspended over the center conductor 15 . In the normal state, FIG. 1( a ), the beams on each ground plane 30 are actuated (solid lines) with electrostatic force applied through SiCr bias lines, while the shunt beam 35 is in the non-actuated state (dashed lines). In this normal state the signal travels directly from the input 40 to the output 45 . In the slow-wave state, FIG. 1( b ), the beams on the ground plane 30 are in the non-actuated state while the shunt beam 35 is actuated to contact the center conductor 15 . The signal thus travels the longer path through the slot 50 in the ground plane 20 , thereby increasing the time delay. FIG. 2 provides a three-dimensional view of the slow-wave device in accordance with the present invention. The physical characteristics of a beam in an exemplary embodiment are given in Table 1 of FIG. 8 . Various alternate dimensions are within the scope of the present invention.
As shown with reference to the flow diagram of FIG. 14 , in an exemplary embodiment, the phase shifters were fabricated on a 500 μm thick quartz substrate (∈ r =3.78, tan δ=0.0004). In an exemplary embodiment of the method of manufacturing of the MEM slow-wave device, the SiCr bias lines are defined first using the liftoff technique by evaporating a 1000 Å layer of SiCr using E-beam evaporation 60 . The measured line resistivity is approximately 2000 Ω/sq. Next a 4000 Å RF magnetron sputtered Si x N y layer is deposited and patterned to form the ground isolation layer 65 . This layer is located where the SiCr bias lines enter the ground conductor. Next the CPW lines are defined by evaporating a Cr/Ag/Cr/Au to a thickness of 150/8000/150/1500 Å using liftoff technique 70 . Next the sacrificial layer (MICROCHEM PMMA), is spin coated and etched in a reactive ion etcher (RIE) using a 1500 Å Ti layer as the mask 75 . The PMMA layer thickness can be varied from 1.5-2 μm by varying the rotational speed of the spinner from 2500-1500 rpm. In a particular embodiment, the thickness of PMMA is optimized to provide a height of 1.8-2 μm. Next, the Ti layer is removed 80 and a 100/2000 Å Ti/Au seed layer is evaporated over the entire wafer and patterned with photoresist to define the width and the spacing of the MEM bridges 85 . The bridges are then gold-electroplated to a thickness of 1 μm 90 , followed by removal of the top photoresist layer and seed layer 95 . The sample is then annealed at 105° and 120° to flatten the bridges 100 before removing the sacrificial PMMA layer. The sacrificial PMMA layer is removed 105 and critical point drying is used to release the MEMS structures 110 . The fabrication steps outlined above are not intended to be limiting and other fabrication methods and processes are within the scope of the present invention.
Measurements of the slow-wave device were performed from 1-50 GHz using a Wiltron 360B vector network analyzer and 150 μm pitch GGB microwave probes. A Thru-Reflect-Line (TRL) calibration was performed using calibration standards fabricated on the wafer. A high voltage bias tee was used to supply voltage through the RF probe to avoid damaging the VNA test ports. Typical actuation voltages are shown in Table 1 of FIG. 8 .
FIG. 3 shows the measured Δφ and S11 for both states of the slow-wave unit-cell. It is seen that Δφ is approximately 41° at 50 GHz and S11 is below −22 dB from 1-50 GHz. The worst-case S21 is −0.17 dB for both states.
The measured unit-cell data was fitted to an ideal transmission line model in a circuit simulator to extract the effective characteristic impedance and effective length in each state. The effective characteristic impedance is approximately 52.1Ω for the normal state and 50.9Ω for the slow-wave state. Using the same approach but with results from a full-wave EM simulation using ADS Momentum™ yielded 51.9Ω (normal) and 50.3Ω (slow-wave). Assuming an effective relative dielectric constant of 2.34, the effective length in the normal state is 600 μm and in the slow-wave state it is approximately 1078 μm, resulting in a slowing factor of 1.8.
The schematic of the phase shifter with ten cascaded slow-wave sections is shown in FIG. 4 . For a 1-bit version, the ground plane or shunt beams in all sections are actuated simultaneously. However, given the SiCr bias line configuration 55 , it is possible to provide independent bias for a multi-bit operation.
FIG. 5 shows the measured S11 for the phase shifter in both states and a comparison of the differential phase shift between measured and simulated results. (The simulated results were obtained by cascading full-wave analysis data for the unit-cells in the circuit simulator.) The measured S11 is below −23 dB for both states from 1-50 GHz. Furthermore, the measured and simulated differential phase shift is within 5%, with a measured value of 420° at 50 GHz. The discrepancy in the predicted phase shift can be attributed to the slight increase in the effective impedance of the fabricated circuit, which is approximately 53.55Ω/50.38Ω versus the design values of 52.1Ω/50.9Ω.
FIG. 6 shows a comparison between the measured insertion loss and EM simulation results for the phase shifter in both states. The measured insertion loss in the normal state is −0.9 dB at 50 GHz, which is higher than the simulated result by 0.3 dB. The graph also shows the measured S21 for a 50Ω CPW line that is 4.6 mm long. It is seen from FIG. 6 that the measured S21 for the slow wave phase shifter in both the states is dominated by transmission line loss for frequency <10 GHz. At higher frequencies, the increase in loss may be due to leakage in the bias circuitry and/or conductor roughness at the edges of the transmission line, which is difficult to account for in the EM simulation. The insertion loss can be improved by creating an air-bridge where the SiCr bias lines enter the ground plane (thereby avoiding the nitride ground isolation layer) and/or by plating the CPW lines.
In an alternate embodiment of the present invention, a MEM capacitor was cascaded with the unit-cell. This design is similar to a DMTL phase shifter with a uniform length of transmission line being replaced with the slow-wave unit-cell. The MEM capacitor is actuated only when the unit-cell is in the slow-wave state. The capacitance ratio is approximately 3.7 (C unloaded =30 fF; C loaded =8 fF) and chosen such that S11 remains less than −20 dB. The phase shifter illustrate in the figure is operated in a 1-bit version although a multi-bit version is possible by addressing the tuning elements individually and is within the scope of the present invention.
FIG. 7 shows the measured S11 for the phase shifter in both states and a comparison of the measured and simulated differential phase shift. The measured S11 is below −19 dB and the worst case insertion loss is approximately −1.9 dB from 1-50 GHz. In comparison to the slow-wave only design, the differential phase shift increases by a factor 17.2% at 50 GHz to 490°, however there is less Δφ per mm. The Δφ per mm can be improved by eliminating the length of CPW line on either side of the MEM capacitor (250 μm per unit-cell). Furthermore, the differential phase shift is also easily adjusted by changing the capacitance ratio of the MEM capacitor, especially when lower return loss performance can be tolerated.
In an additional embodiment, a 2-bit version of the capacitively loaded phase shifter was designed to provide Δφ of 45° and 90° at 25 GHz. Experimental results for the 2-bit version resulted in Δφ of 49.3° and 81.5° with S11<−21 dB through 50 GHz and the worst case insertion loss <1.15 dB.
In accordance with the present invention, a true-time-delay CPW phase shifter operating from 1-50 GHz is presented that utilizes slow-wave MEM sections. The measured S11 for a slow-wave unit-cell is below −20 dB with a differential phase shift of 34° at 40 GHz. A phase shifter comprised of 10 slow-wave unit-cells is shown to have S11 less than −20 dB with a phase shift of 317° at 40 GHz. The predicted and measured results for the phase shift agree to within 5%. In one embodiment of the invention, the goal was to keep S11 below −20 dB. However, if the constraint on S11 is relaxed to −10 dB the simulated phase shift is approximately 450° at 40 GHz. The unit-cells in the phase shifter can be addressed individually for a multi-bit operation and can possibly result in 10 phase states.
In an additional embodiment, an electronically tunable Thru-Reflect-Line (TRL) calibration set that utilizes a 4-bit true time delay MEMS phase shift topology in accordance with the present invention is provided. With reference to FIG. 9 , a 4-bit phase shifter is illustrated consisting of 10 cascaded slow-wave unit cells and is designed to provide small variations in the impedance around 50Ω on a 500 μm thick quartz substrate. The states of the phase shifter in accordance with this embodiment provide Δφ of 45°, 90°, 180° and 225° at 35 GHz. In an exemplary embodiment, measurements of the electronically tunable TRL were performed from 1-50 GHz. A multi-line TRL calibration was performed using conventional calibration standards fabricated on the wafer. FIG. 10 illustrates the measured S11 for the phase shifter in all the states, while FIG. 11 illustrated the measured Δφ and worst case S21 (dB) for the 4-bit phase shifter. As such, a true-time-delay 4-bit CPW phase shifter operating from 1-50 GHz is within the scope of the present invention that utilizes slow-wave MEMS sections. The experimental results for this embodiment demonstrate S11 less than −21 dB through 50 GHz with Δφ/dB of approximately 317°/dB at 50 GHz. Accordingly, an electronically tunable calibration is made possible by realizing all the line standards using the multi-bit phase shifter in a multi-line TRL. The Tunable TRL device and method in accordance with the present invention provide for an efficient usage of wafer area while retaining the accuracy associated with the TRL technique, and reduces the number of probe placements from five to two, with potentially no change in probe separation distance.
In yet another embodiment, a reconfiguration MEMS-based transmission line in which there is independent control of the propagation delay and the characteristic impedance is provided. In accordance with this embodiment, separate control of inductive and capacitive MEMS slow-wave devices in accordance with the present invention are used either to maintain a constant LC product (constant Z o ) or a constant L/C ratio (constant β), while changing the ratio or product, respectively. With reference to FIG. 12 , a device in accordance with this embodiment is shown in which a slow-wave device with metal-air-metal (MAM) capacitors 60 at the input and the output of the slow-wave device are provided. With this embodiment, Z o -tuning is realized by operating the slow-wave section in conjunction with the MAM capacitors: the low-Z o mode corresponds to the normal state with actuated MAM capacitors, which the high-Z o is realized in the delay state with non-actuated MAM capacitors. Maintaining a constant propagation constant (β) with Z o -tuning is achieved by proper selection of the capacitance ratio (C r =C max /C min ). Specifically, Δφ due to the MAM capacitor (Δφ MAM ), separated by a 270 μm long uniform CPW line, offsets the Δφ due to the slow-wave section (Δφ slow-wave ). For a given spacing (s) between capacitors and the total length (L), equation (2) is used to calculate C r .
Δ
ϕ
=
(
ω
L
t
C
t
)
×
[
1
+
C
b
sC
t
-
1
+
C
r
C
b
sC
t
]
L
rad
(
2
)
Where, L t and C t are the per-unit-length inductance and capacitance in the normal state. Using (2), C r =2.6 for Δφ=46′, s=270 μm, C b =24 fF, L t =0.33 nH/mm, Ct=0.07 pF/mm, and L=740 μm.
The different Z o levels are determined by considering the transmission line section between MAM capacitors (the slow-wave section) as a uniform CPW line. The effective impedance (Z eff ) is then calculated using (3). For the distributed parameters used herein, Z eff can be set to approximately 38Ω or 50Ω; parasitic loading of the shunt beam and other discontinuity effects increase the actual levels to 40/52Ω values stated above.
Z
eff
=
L
t
1
+
C
b
sC
t
(
3
)
With reference to FIG. 12 , a 1-bit phase shifter with maximum phase shift by actuating the MAM capacitors in the delay state of the slow-wave sections is illustrated. FIG. 13 illustrates the measures S11 for the phase shifter in accordance with this embodiment in both states and a comparison of the differential phase shift between the measured and simulated results.
Accordingly, a method and apparatus is provided that has application in many areas. Including, but not limited to, dynamically-controlled planar transmission line standards for electronic-calibration of vector network analyzers. In particular, standards for use with the Thru-Reflect-Line (TRL) calibration method and other calibration methods that include the use of two or more lines of varying electrical length are provided. Additional uses include, tunable distributed filter topologies which incorporate transmission line “stubs” of varying electrical length that are spaced by varying electrical lengths, and other tunable components that operate on the distributed transmission line principle, including but not limited to couplers, impedance matching networks, balanced-to-unbalanced transformers (BALUNS), and various transitions between different planar transmission line topologies, such as coplanar waveguide to slotline transitions.
It will be seen that the advantages set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. Now that the invention has been described, | 4y
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of International Application No. PCT/EP2010/062332, filed Aug. 24, 2010, which claims priority to German Patent Application No. 10 2009 038 780.3, filed Aug. 25, 2009 and to U.S. Provisional Patent Application No. 61/236,746, filed Aug. 25, 2009, the disclosure of which are all hereby incorporated in their entirety by reference.
TECHNICAL FIELD
The technical field relates to a device for ensuring the protection of pipes against rupture, a device for testing a device for the protection of pipes against rupture and also a vehicle having at least one device for the protection of pipes against rupture that is suitable for implementing the process in accordance with the present disclosure.
BACKGROUND
Numerous examples of apparatus and systems containing pipes carrying liquids include a device for protecting pipes against rupture. These can be found in both household appliances, such as washing machines or dishwashers, and also in more technically complex hydraulic systems in aircraft. There, they are also described by the term “hydraulic fuse”. These devices prevent fluids from escaping completely through these leakage points. Moreover, where they are used in a hydraulic system in an aircraft, their effect is to bring about an automatic shutdown of a defective pipe branching and to ensure that other consumer units upstream of the protection device can still be supplied with hydraulic fluid.
Such devices for the protection of pipes against rupture usually include an internal closing element that switches automatically into a closed position once a pre-determined volume flow is exceeded, thus preventing any further loss of fluid. However, when used in particular in an aircraft or in any other system where safety is paramount, the problem arises that such protection devices that are incorporated into hydraulic systems cannot be inspected (in situ). Under normal operating conditions, no volume flow can be generated that can close the pipe rupture protection device. In addition, other demands, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
In one embodiment, this disadvantage is reduced or eliminated altogether, for example, by proposing a device for protecting against pipe rupture, in which a safety inspection can be carried out without the volume flow for the system carrying the fluid exceeding a permissible maximum.
An exemplary device for the protection of pipe rupture includes a housing with an inflow and an outflow, with a closing element that is movably mounted in the housing having a front face facing the inflow and a closing face facing the outflow, having at least two flow channels extending from the inflow to the outflow, with at least one orifice arranged in the flow channels for producing a pressure drop in a fluid flowing from the inflow to the outflow and with at least one retaining element arranged between the outflow and the closing element. A device of this nature may have at least one test closure that closes at least one of the flow channels, so that the resulting flow rate is increased in the remaining flow channels, thereby causing the closing element to move into the closed position.
The basic functioning of such a device is variously described below. The device in accordance with the present disclosure for protecting against pipe rupture is switched in series with a pipeline, so that in normal conditions the fluid being carried flows unimpeded through the device. A housing inside the device having an inflow and an outflow for the fluid contains a movably mounted closing element. This closing element has a front face that faces the inflow. The closing element also comprises a closing face, which faces the outflow. A fluid flowing through the inflow flows through at least two flow channels around the closing unit towards the outflow and exits at this point. In an area between the closing element and the outflow, there is at least one orifice arranged through which the fluid flows. Because of the increased flow resistance, this causes a pressure drop. This pressure drop is essentially quadratically dependent on the volume flow of the fluid. The pressure of the fluid prevailing at the inflow acts on the front face of the closing element, while the pressure prevailing at the outflow behind the orifice through which the flow has passed acts on the closing face of the closing element in the opposite direction. In addition, the force of a retainer element acts on the closing face, which is also positioned facing the inflow or the front face of the closing element.
Under normal conditions, i.e. when the fluid volume flow lies within the normal operating range, an increased force acts on the closing face in such a way that the device in accordance with the present disclosure remains in the open position. The force of the retainer element is calculated in such a way that this additional force increases when a pre-determined maximum volume flow is reached and the force acting on the front face of the closing element corresponds to or slightly exceeds the force acting on the closing face. This results in a movement of the closing element into a closing position.
The force excess on the front face can be explained by the fact that, as mentioned above, the pressure drop through the orifice between the closing face and the outflow is essentially quadratically dependent upon the volume flow. Therefore, as the volume flow increases, the resulting pressure differential between the inflow pressure and the outflow pressure also increases, so that, at a given volume flow, the inflow pressure is sufficiently high in relation to the resetting force acting on the closing face to move the closing element into its closing position.
The number of flow channels within the device in accordance with the present disclosure is neither strictly stated nor limited. However, for the purpose of technical manufacturing simplicity, it could be appropriate to use two or four flow channels. Clearly, there could be three, five, six or more flow channels, which could be combined with a test closure. In a typical use of two flow channels, closing one of the flow channels would have the effect of doubling the flow speed in the other channel and increasing the resulting pressure drop through the orifice by a factor of four. This fluid volume flow between the inflow and the outflow could in itself be sufficient to generate a force excess at the front face and to move the closing element into its closing position.
Unlike conventional devices already known to the state of the art, devices in accordance with the present disclosure may include a test closure arranged in the housing, which can close at least one flow channel in order to increase the resulting volume flow, that is to say the flow speed, in the other flow channels. As a result of the relationship between the flow speed and the pressure drop, the closure of one flow channel will result in a significantly greater pressure drop through the orifice between the inflow and the outflow and produce a force excess at the front face of the closing element, thereby moving the closing element into its closing position. By closing the test closure a state is achieved inside the device in accordance with various embodiments that brings about the closure of the device.
This structurally simple solution is a very effective method of testing the functioning of a device for ensuring the protection of pipes against rupture in situ, without any need to dismantle the system or take it apart. This saves the operator of a safety-relevant system, for example, the operator of an aircraft with at least one safety-relevant hydraulic system or other systems, considerable maintenance costs without having to increase the complexity of the system or the plant.
In order to prevent a situation in which, because of any dynamic effects from the rapid opening and closing of valves or the like, the device in accordance with the present disclosure may briefly close, the closing element can be movably housed in a bushing section within the housing, so that sufficient fluid may flow into the bushing section to maintain the constancy of the volume so as to actuate the closing element. This flow of fluid can be limited by a cover for the bushing section arranged on the front side of the closing element having an integrated choke directed towards the inflow, so that the movement of the closing element is damped. When the maximum volume flow is reached or exceeded and a force excess is present at the front face, the closing element is forced into its closing position, whereby the space formed between the closing element and the cover slowly fills with fluid thus limiting the speed of the closing element. In this way, pressure or flow peaks can be absorbed.
It is conceivable that a number of test closures could be provided for a number of flow channels, so that two or more test closures would need to be closed in order to be able to conduct a functioning test.
In a particularly advantageous embodiment, the test closure is movably arranged on the housing so that by moving it into a closing or an opening position, the flow channel is correspondingly closed or opened.
In a further embodiment, the test closure could be mounted in such a way that it can be rotated and include a closing face, which closes in such a way that it is flush with a surrounding wall of the respective flow channel and in a closing position closes the respective flow channel. The closing position could be achieved by starting from the closing position with a rotation of the test closure through an angle of rotation of 180°.
In a further embodiment, it could be an advantage that the test closure can be deflected longitudinally into the respective flow channel, so that—for example—a closing or opening of the respective flow channel can be effected by pressing or pulling. For this purpose, the test closure could be spring-mounted and could be released again once the closing position of the closing element has been reached.
In another embodiment, the test closure is so designed that a colored warning sign is visible when it is in its closing position, thus giving a warning before the device is used.
It is also conceivable that the test closure could be operated and locked without being activated, possibly for safety reasons or because under pressure the forces required to activate it were too high. At the end of the test, the device would need to be reset by hand. The special tool required for this purpose could be marked for example with an elongated red warning flag, as is customary in aviation.
Moreover, it could be especially advantageous if the test closure were mechanically constructed in such a way that it could only be switched into a closing position by using a special tool and this special tool could only be removed from the test closure if the latter is in an opening position. This would be especially effective in preventing an involuntary closing of the test closure.
A process for the testing of a device for the protection of pipes against rupture is also disclosed, which comprises the steps for operating the higher level system, for closing at least one test closure, for closing down the entire system when the closing position of the closing element is reached, and a final optional operation of the higher level system.
A device is also provided for protecting pipes against rupture in an aircraft and also by an aircraft having at least one hydraulic system and at least one device in accordance with the present disclosure for the protection of pipes against rupture.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features, advantages and possible applications of the present disclosure will become apparent from the following description of the different embodiments and the drawings. At the same time, all features that are described and/or depicted in the drawings may be used both individually and in any combination in the context of the present disclosure regardless of the manner in which they are presented in the individual claims or of their retroactive applications. The drawings also contain the same reference symbols for the same or similar objects.
FIG. 1 is an illustration of a device in accordance with an embodiment in a lateral sectional view;
FIG. 2 is an illustration of the process in accordance with an embodiment in a schematic block diagram;
FIG. 3 is an illustration of an aircraft having at least one hydraulic system and at least one integrated device in accordance with an embodiment for the protection of pipes against rupture; and
FIGS. 4 a to 4 c show various exemplary test closures.
DETAILED DESCRIPTION
FIG. 1 shows a lateral section of a device in for the protection of pipes against rupture 2 , which includes a housing 4 having an inflow 6 and an outflow 8 , a locking element 10 that is arranged in a movable manner in a bushing section 12 , a front face 14 and a closing face 16 . In the housing 4 , there is also a retaining element 18 , which is supported through a spring 20 against the housing in the vicinity of the outflow. Between the locking element 10 and the retaining element 18 there are number of orifices 22 , which produce a pressure drop in one of the fluids flowing from the inflow 6 to the outflow 8 .
Between the inflow 6 and the orifices 22 , two flow channels 24 and 26 can be seen in this drawing, although more flow channels can also be arranged in the housing 4 . If fluid flows through the inflow 6 into the two flow channels 24 and 26 , it passes through the orifices 22 and in so doing it undergoes a pressure drop. Effectively, this pressure drop increases quadratically in relation to the flow speed within the flow channels 24 and 26 with the result that, for example, if the volume flow is doubled, a four-fold pressure drop can be expected through the orifices 22 .
Along the plane of the drawing, the locking element 10 can move to the right towards the outflow 8 , whereby, when it reaches the edges 28 , it reaches a closing position in which the orifices 22 are closed, so that the flow of fluid between the inflow 6 and the outflow 8 is completely interrupted. The movement of the locking element 10 into this closing position is brought about by the increasing pressure difference between the pressure level at the inflow 6 and the pressure level at the outflow 8 . If the force at the front face 14 of the locking element 10 exceeds the resetting force acting on the closing face 16 produced by the pressure at the outflow 8 and the spring 20 , the closing element is forced into its closing position. This position may be left again if the fluid pressure is interrupted at the inflow 6 .
For compensating pressure or flow peaks caused by rapid opening and closing movements of valves or the like in a hydraulic system, a cover 32 comprising a choke system is arranged on the bushing section 12 . If the locking element 10 is forced into its closing position, the hollow space located between the locking element 10 and the cover 32 must fill up with fluid in order to preserve the volume constancy in order to permit a movement of the locking element 10 . The choke 30 can be designed in such a way that a damping effect on the movement of the locking element 10 can be achieved very easily and, in an ideal case, this can compensate for pressure or flow peaks at the inflow 6 .
In order to enable the device in accordance with the present disclosure to be tested, a test closure 34 is arranged on the housing 4 which can close the upper flow channel 26 . This is effected by the test closure 34 having a closing face 36 , which in an opening position of the test closure lies flush with a wall 38 of the flow channel. When the test closure 34 is rotated in its opening position through 180° through its own axis, the closing face 36 , depending on the corresponding geometric design of the test closure, turns in such a way that the flow channel 26 is completely closed. For this purpose, the flow channel 26 could have a section, the central axis of which forms an angle of 45° with the longitudinal axis of the device in accordance with the present invention, so that the closing face 36 is also at an angle of 45°. When rotated through an angle of 180°, the closing face 36 extends vertically to the wall 38 and then covers the entire cross-section of the respective flow channel 26 .
If the test closure 34 is moved into a closing position, the volume flow in the upper flow canal 26 comes to an end, with the result that the entire fluid flow passes through the lower flow channel 24 . This assumes that the device 2 comprises only two flow channels, 24 and 26 . The pressure loss at the orifices 22 increases by a factor of four because the flow speed has now doubled. Given an appropriate design of the spring force, this significantly higher pressure loss could be sufficient to build up a force excess at the front face 14 of the locking element 10 , leading to the locking element 10 being moved into its closing position.
The drawing is only intended to be an example, so that the number of flow channels arranged in the housing 4 could be increased. Similarly, any number of test closures could be distributed along the flow channels and these could even function on the basis of different operating principles. In this way, test closures could be imagined that are pressed into a corresponding flow channel 22 .
FIG. 2 illustrates an exemplary method in accordance with an embodiment in the form of a block diagram. After the initiation 40 of the operation of a higher level system, for example a hydraulic system, all existing test closures 34 will be closed 42 one after another and the reaction of all devices 2 that are arranged in the higher level system will be tested 44 . After this test has been completed, the operation of the higher level system will be interrupted 46 , so that the locking element 10 of each of the devices 2 will be moved in the direction of the inflow 6 . Subsequently, a new initiation 48 of the operation of the higher level system can take place.
Furthermore, FIG. 3 shows an aircraft 50 that is equipped with at least one hydraulic system 52 , on the pipe system of which 54 a device for the protection of pipes against rupture in accordance with one embodiment has been arranged.
FIG. 4 a illustrates a test closure 56 having a bevelled and rotatably mounted closing body 58 , which can be rotated into either an opening or a closing position. This principle corresponds to the test closure 34 shown in FIG. 1 . A further special feature is a slotted bushing 60 , which protects an operating end 62 of the test closure 56 from any unauthorized or unintentional operation. With the use of an appropriate tool 90 , the operating end 62 can be engaged and the test closure 56 can be operated. In one example, the test closure 56 is constructed in such a manner that it can only be brought into a closing position through the use of the special tool 90 and this special tool 90 can only be removed when the test closure 56 is in an opening position.
FIG. 4 b shows a further possible test closure 64 , which has a closing element 66 that can be pressed into position. The test closure 64 can be operated by an operating end 68 in the form of a button, for example. In one example, the test closure 64 is spring-mounted with a spring 92 and without any external influence reverts independently from its closing position to its opening position.
Furthermore, FIG. 4 c shows an addition test closure 70 , which, by being rotated over a milled recess 72 , into which a pin 74 engages, pivots a closing element 76 in an axial direction.
All these examples are to be understood as being exemplary. It is understood that appropriate sealing rings 78 or the like are used for sealing purposes.
Finally, it must be stressed that the terms “comprising” are not intended to preclude other elements or steps and that “a” or “an” do not preclude a plural form. It is also stressed that features or steps, described by means of references to one of the above embodiments, can also be used in combination with other features or steps of other embodiments described above. Reference marks contained in the claims are not to be seen as being a limitation. Moreover, while at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. | 4y
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FIELD OF THE INVENTION
This invention relates to motor vehicle door handle assemblies and, more particularly, to a simplified assembly providing both inside and outside door handle assembly functions.
BACKGROUND OF THE INVENTION
Motor vehicle door assemblies typically include an outside door handle assembly, an outside door handle linkage for connecting the outside door handle to the door latch, an inside door handle, and an inside door handle linkage for connecting the inside door handle to the door latch. Whereas this basic arrangement is satisfactory in providing opening of the door from either inside or outside of the door, the total door handle assembly tends to be rather complex and rather expensive both from a materials standpoint and a labor/assembly standpoint.
SUMMARY OF THE INVENTION
This invention is directed to the provision of improved motor vehicle door handle assembly.
More particularly, this invention is directed to the provision of a motor vehicle door handle assembly wherein the outside door handle assembly and the inside door handle assembly share common elements to simplify the construction and operation of the overall assembly and reduce the overall materials and labor cost of the assembly.
The invention is directed to a motor vehicle door handle assembly comprising an outside door handle, an outside door handle linkage for connecting the outside door handle to a door latch, an inside door handle, and an inside door handle linkage for connecting the inside door handle to the door latch.
According to the invention, the outside and inside door handle linkages share a common spring element which is interposed in each linkage and acts to yieldably resist opening movement of the inside and outside door handles and provide a spring biased return movement of the inside and outside door handles upon release of the handles. This arrangement simplifies the overall construction of the total door handle assembly without any sacrifice in the performance of either the inside or the outside door handle assembly.
According to a further feature of the invention, the outside and inside door handle linkages further share a common damper mechanism which is interposed in each linkage and acts to cushion the spring biased return movement of the door handles. With this arrangement, a single damper mechanism acts to provide a soft, cushioned return of either the outside or the inside door handle to its rest position upon release of the handle.
According to a further feature of the invention, the assembly further includes a lost motion means allowing movement of either door handle to an open position without corresponding opening movement of the other door handle. This arrangement allows the utilization of shared componentry as between the inside and outside door handle assemblies without causing interference between the operation of the inside and outside door handles.
According to a further feature of the invention, the outside door handle linkage and the inside door handle linkage further share a common latch actuator element positioned at a location remote from the latch and a common linkage element for interconnecting the latch actuator element and the latch; and the common latch actuator element is moved to actuate the common linkage element and thereby actuate the latch in response to opening movement of either the outside door handle or the inside door handle. This arrangement further simplifies the overall construction of the total door handle assembly without sacrifice of handle performance.
According to a further feature of the invention, the common spring element resiliently resists movement of the common latch actuator element in an unlatching direction in response to opening movement of the outside door handle or the inside door handle and returns the common latch actuator to a rest position upon release of the actuated handle. This common spring arrangement further simplifies and reduces the cost of the total door handle assembly.
According to a further feature of the invention, the common latch actuator element comprises a latch lever mounted for pivotal movement about a fixed axis; the common spring element comprises a coil spring centered on the axis and resisting movement of the latch lever in an unlatching direction; and the assembly further includes a common damper mechanism including a housing containing a viscous fluid and a vane movable in the housing against the resistance of the viscous fluid in response to pivotal movement of the latch lever. This arrangement allows the common latch lever to actuate the latch, mount the spring, and drive the damper mechanism.
According to a further feature of the invention, the common damper mechanism further includes a gear driving the vane and the latch lever includes gear teeth formed on the lever concentric with the axis and driving the gear. This arrangement provides a simple means of actuating the damper utilizing the pivotal movement of the latch lever.
According to a further feature of the invention, the outside door handle linkage includes an outside linkage lever pivotally mounted at one end thereof proximate the remote location for pivotal movement about a fixed axis and operatively connected proximate a free end thereof to the outside door handle; the latch lever is pivotally mounted at one end thereof on the axis and is operatively connected to the inside door handle and to the shared common linkage element; and the lost motion means includes a first lost motion connection between the one ends of the levers operative to allow relative pivotal movement between the levers. This arrangement provides a simple means of driving the latch lever either from the outside door handle or from the inside door handle.
According to a further feature of the invention, the first lost motion connection provides a driving connection between the levers in response to opening movement of the outside door handle and allows relative movement between the levers in response to opening movement of the inside door handle so as not to disturb the outside door handle.
According to a further feature of the invention, the lost motion means further includes a second lost motion connection between the latch lever and the inside door handle whereby pivoting of the latch lever in response to opening movement of the outside door handle does not disturb the inside door handle.
According to a further feature of the invention, the inside door handle linkage includes a linkage element; the second lost motion connection comprises a mounting structure on the latch lever remote from the pivot axis slidably receiving one end of the inside door handle linkage element; and the one end of the inside door handle linkage element is headed so as to allow unlatching movement of the latch lever in response to opening movement of the inside door handle while not disturbing the inside door handle in response to unlatching movement of the latch lever in response to opening movement of the outside door handle.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary view of a motor vehicle including a door embodying the door handle assembly of the invention;
FIG. 2 is a perspective, somewhat schematic view of the motor vehicle door seen in FIG. 1;
FIG. 3 is a perspective view of the door handle assembly of the invention;
FIG. 4 is a perspective view of an outside door handle assembly employed in the door handle assembly of the invention;
FIG. 5 is a perspective view of an outside door handle employed in the outside door handle assembly;
FIG. 6 is a perspective, fragmentary view of a common latch actuator mechanism employed in the invention door handle assembly;
FIGS. 7 and 8 are cross-sectional views taken respectively on lines 7 — 7 and 8 — 8 of FIG. 6;
FIG. 9 is a fragmentary plan view of the common latch actuator mechanism; and
FIGS. 10 and 11 are detail perspective views of elements employed in the common latch actuator mechanism.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention door handle assembly 10 is seen in FIG. 1 in association with a fragmentarily shown motor vehicle 12 including a windshield 14 , a front quarter panel 16 , a hood 18 , an A pillar 20 , a sill 22 , a B pillar 24 , and a door 26 positioned in the door opening defined by the A pillar 20 , front quarter panel 16 , sill 22 , and B pillar 24 .
Door 26 (FIG. 2) includes an inner skin 26 a , an outer skin 26 b , and a latch 28 mounted on a shut face 26 c of the door and arranged for coaction in known manner with a bolt or striker 30 mounted on the B pillar 24 .
Motor vehicle door handle assembly 10 (see also FIG. 3) includes an outside door handle assembly 32 , an outside door handle linkage 34 , an inside door handle assembly 36 , an inside door handle linkage 38 , and a common latch actuator assembly 40 .
Outside door handle assembly 32 (FIGS. 3, 4 and 5 ) includes a handle 42 and a housing or escutcheon 44 .
Housing 44 is mounted in a suitable opening in the outer skin 26 b of the door and has a generally oval configuration. Housing 44 includes a peripheral rim portion 44 a surrounding a central recessed bowl portion 44 b . The inner face 44 c of the housing defines an inwardly projecting hollow guide portion 44 d and spaced pillar portions 44 e and 44 f.
Handle 42 has an elongated configuration and includes a main body grip portion 42 a and an arm portion 42 b extending inwardly from a rear end 42 c of the handle. Front end 42 d of the handle includes a pivot portion 42 e for pivotally mounting the handle in known manner to the front end 44 g of the housing, and the arm 42 b extends inwardly and slidably through guide portion 44 d of the housing to dispose an opening 42 f at the free end of arm portion 42 b within the interior of the door.
Outside door handle linkage 34 (FIGS. 6, 7 , 9 and 10 ) comprises a lever 46 and a pin 48 .
Lever 46 is pivotally mounted at one end 46 a thereof on a pivot pin 47 extending between the inner ends of housing pillars 44 e and 44 f . The end 46 a of lever 46 is configured to define a through bore 46 b receiving pivot pin 47 , a hub or journal portion 46 c centered on bore 46 b , and an arcuate driver portion 46 d centered on bore 46 b outwardly of hub 46 e . Arcuate driver portion 46 f may have an arcuate extent of, for example, 110° and has an axial extent exceeding the axial extent of hub portion 46 b so that arcuate driver portion 46 d overhangs hub portion 46 c.
Pin 48 is fixedly secured to the other end 46 e of lever 46 and extends in a direction opposite to the extent of hub portion 46 c and driver portion 46 d . Pin 48 is received in the opening 42 f of arm portion 42 b of handle 42 so that pivotal movement of the handle about its front end 42 d has the effect, via the driving interconnection between pin 48 and opening 42 e , of pivoting lever 46 about the fixed axis 49 defined by pin 47 .
Inside door handle assembly 36 (FIGS. 2 and 3) includes a handle 50 and a housing or escutcheon 52 .
Housing 52 is fixedly secured in a suitable opening in the inner skin 26 a of the door and defines a main body portion 52 a , defining a central concavity 52 b , and a cable mounting portion 52 c.
Handle 50 is suitably mounted in the concavity 52 b of main body housing portion 52 a for pivotal movement about a pivot pin 53 carried by housing 52 and includes a gripping portion 50 a for grasping by the vehicle operator and a cable attachment end portion 50 b.
Inside door handle linkage 38 (FIGS. 2, 3 and 6 ) includes a cable assembly 54 and a bracket 56 .
Cable assembly 54 is of the Bowden type and includes a central core or cable 58 , an outer sheath 60 , and a fitting 62 .
Bracket 56 is fixedly secured to the inner skin 26 a of the door at a location proximate the outside door handle assembly and fitting 62 is fixedly secured at the outboard end of the bracket and extends downwardly from the bracket.
Sheath 60 is fixedly secured at one end in the lower end of fitting 62 and at its other end in the mounting portion 52 c of the inside door handle housing 52 .
Cable 58 is connected at one end to inside handle cable attachment portion 50 b and extends through housing mounting portion 52 c , through sheath 60 , and through fitting 62 to define an upper cable end 58 a extending upwardly from fitting 62 and defining a head 58 b at its upper free end. It will be seen that pivotal opening and closing movement of inside door handle 50 has the effect of sliding cable free end 58 a upwardly and downwardly within fitting 62 .
Common latch actuator assembly 40 (FIGS. 6, 7 , 8 , 9 and 11 ) includes a latch actuator lever 64 , a spring element 66 , and a damper mechanism 68 .
Latch actuator lever 64 includes an inner end 64 a and an outer end 64 b . Outer end 64 b includes an aperture 64 c for receipt of the upper end 70 a of a latch actuator rod or linkage 70 . The inner end 64 a of the lever is configured to define a central bore 64 d for receipt of pivot pin 47 , a hub or journal portion 64 e centered on central bore 64 d , and an arcuate driver portion 64 e centered on hub portion 64 d outwardly of hub portion 64 e , and a gear segment 64 f centered on bore 64 d at a location circumferentially removed from driver portion 64 e . Driver portion 64 e may have an arcuate extent, for example, of 180° and has an axial extent exceeding the axial extent of hub portion 64 e so that the arcuate driver portion extends axially beyond the hub portion. Lever 64 further defines a spring mount hub portion 64 g concentric with bore 64 d and through which pivot pin 47 extends for mounting in housing pillar 44 f . Lever 64 further includes a mounting structure 64 h positioned between inner and outer ends 64 a and 64 b and having a central bore sized to slidably receive the upper end 58 a of cable 58 . The headed end 58 b of the cable precludes separation of the cable from the mounting portion 64 h , provides a driving connection between the cable and the lever 64 , and allows lost motion between the cable and the lever 64 .
In the assembled relation of levers 46 and 64 , pivot pin 47 passes centrally through aligned bores 46 b and 64 d , hub portions 46 c and 64 e slidably interface, and arcuate driver portion 46 d is located circumferentially within the missing arcuate portion of arcuate driver portion 64 e . It will be seen that driver portions 46 d and 64 e allow driving movement of lever 46 with respect to lever 64 in one direction while allowing lost motion movement between lever 64 and 46 in the opposite direction.
Spring element 66 comprises a coil spring and is mounted on spring mount portion 64 g of lever 64 with one end 66 a of the spring hooked under the lower edge of lever 64 and the other end 64 b of the spring suitably anchored with respect to outer door handle housing 44 . Spring 66 acts to resist downward pivotal movement of lever 64 about axis 49 and returns lever 64 upwardly to a rest position in the absence of forces pivoting the lever downwardly.
Damper mechanism 68 includes a cylindrical housing 72 fixedly secured to pillar 44 f ; a shaft 74 centrally mounted within the housing; a vane structure 76 mounted on the shaft for rotary movement with the shaft within the housing, a gear 78 mounted on a free end of shaft 74 exteriorly of the housing 72 and meshingly engaging with gear segment portion 64 f of lever 64 , and a viscous fluid 80 positioned within the housing in surrounding relation to vane 76 . It will be seen that pivotal movement of lever 64 about axis 49 has the effect of rotating gear 78 whereby to rotate vane 76 within housing 72 against the viscous resistance of fluid 80 so as to provide a viscous damping resistance to the pivotal movement of lever 64 .
In the operation of the invention door handle assembly, either the outside door handle may be pivoted to unlatch the latch 28 or the inside door handle may be pivoted to unlatch the latch 28 , the opening movement of the respective handle in each case not disturbing the other handle by virtue of the lost motion connections provided at the common latch actuator assembly 40 . Specifically, as the outside door handle is pivoted outwardly to an unlatching position, handle arm 42 b engages pin 48 to pivot lever 46 about axis 49 . As lever 46 is pivoted about axis 49 , arcuate driver portion 46 d of lever 46 engages an end face 64 h of arcuate driver portion 64 e of lever 64 to pivot lever 64 downwardly and move rod 70 downwardly in a manner to unlatch latch 28 . As the lever 64 is pivoted downwardly, the upper end 58 a of cable 58 slides in a lost motion manner in mounting structure 64 h so as not to disturb the inside door handle assembly.
Conversely, when inside door handle 50 is pivoted outwardly to unlatch the latch, cable 58 pulls lever 64 downwardly by virtue of cable head end 58 b to move rod 70 downwardly in an unlatching direction. As the lever moves downwardly the leading face 64 i of arcuate driver 64 e moves in an idling, lost motion manner within the gap 80 defined between the trailing face 46 f of driver segment 46 d and the leading face 64 i of arcuate driver 64 e to ensure that the opening movement of the inner door handle does not disturb the outer door handle.
As lever 64 is pivoted downwardly to unlatch the latch in response to either opening movement of the outside door handle or opening movement of the inside door handle, spring 66 resiliently resists the downward movement to provide a positive “feel” for the opening movement of the respective handle and the spring acts in response to release of the respective handle to positively return the handle to its rest position by exerting an upward pivotal force against lever 64 . Further, as lever 64 is pivoted downwardly or upwardly about axis 49 , damper mechanism 68 acts to provide a damping force resisting the latching or unlatching movement of the mechanism, thereby to cushion the latching and unlatching movement of the mechanism and in particular to mollify the return movement of the inside door handle and the outside door handle upon release of the handle to preclude objectionable slapping noises as the handle resumes its rest position with respect to the respective housing.
The invention door handle assembly, by providing many common elements in the outside door handle linkage assembly and the inside door handle linkage assembly, significantly reduces the cost of the system without any sacrifice in the performance of the system. Specifically, the use of a common latch actuator assembly allows the use of a common spring to provide spring biased movement of both the inside and outside door handles and the common latch actuator arrangement further allow the provision of a common damping mechanism to provide a damping action with respect to the closing movement of both the inside and outside door handles. The overall effect of the invention is to provide a total inside/outside door handle assembly for a motor vehicle having performance equal to or superior to prior art systems employing individual inside and outside linkages and at a price that is significantly less than the combined price of the inside and outside door handle assemblies by virtue of both reduced parts costs and reduced labor costs.
Whereas a preferred embodiment of the invention has been illustrated and described in detail, it will be apparent that the various changes may be made in the disclosed embodiment without departing from the scope or spirit of the invention. | 4y
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This application is a division of application Ser. No. 07/879,595, filed on May 7, 1992, now U.S. Pat. No. 5,226,999.
BACKGROUND OF THE INVENTION
The present invention relates to the recapping of tires; more particularly, it proposes a new method of removing the tread from tires, that is to say, a new method of removing a worn tread before recapping.
Tires have a crown reinforcement, generally arranged above the carcass ply of the tire. More and more frequently these crown reinforcements have a reinforcement arranged at zero angle, that is to say, oriented in the circumferential direction of the tire so as to constitute a hoop. The latter may be arranged either over the entire width of the crown of the tire or over a part thereof, for instance over the side edges. It is possible to develop these zero-degree reinforcements in various ways. For example, a ply is produced, the width of which corresponds to the width of the zero-degree reinforcement, by winding in one or more turns and forming a splice by a slight superpositioning of the circumferential ends of the ply. Another technique consists in using a strip comprising a plurality of parallel cords, for instance ten, and winding this strip until obtaining the desired reinforcement.
A zero-degree reinforcement can also be formed from a single cord which is wound on the crown of the tire in order to produce the desired reinforcement. In these latter two cases, the cord is not placed exactly at zero degree since there is a very small angle corresponding to the laying pitch of the cord. However, it is customary to speak of all these embodiments as having a zero degree angle.
In the present description, the expression "cord" is to be understood in the very broadest sense; a reinforcement cord is formed either by a single cord or by an assembly constituting a cable, or by any equivalent type of assembly, and this whatever the nature of the cord.
Before proceeding with the recapping of a tire, it is necessary to remove what remains of the tread which has been used. In order to remove the tread, one effects a machining operation with a cutting tool until freeing the carcass of the tire from any trace of tread rubber. This operation is well known to those skilled in the art.
SUMMARY OF THE INVENTION
The present invention proposes a new manner of removing the worn tread for the preparation of the carcass for recapping. In order to remove the tread, it is proposed to use the zero-degree cord when the crown reinforcement has one. In fact, it has been found that the tread of a tire, the crown reinforcement of which contains a spirally wound zero-degree cord over the entire width of said crown, can be removed by grasping at least one of the ends of said cord and pulling it in the direction transverse to said cord in order to remove it completely from the crown reinforcement. A zero-degree reinforcement formed by a single cord wound on the crown lends itself perfectly to the removal of the tread in accordance with the present invention.
It is also noted that zero-degree reinforcements formed from a strip also lend themselves to this new method of tread removal, and this even better when the strip comprises a small number of cords, for instance three cords. In this case, all the cords of the strip must be grasped simultaneously in order to remove the tread by pulling in transverse direction on the cords.
In the following description, the expression "single cord" specifically designates a zero-degree reinforcement produced with a single assembly or unit cord; otherwise, the expression "cord" covers both a single cord and a strip formed of a small number of cords.
This tread removing method can furthermore be used when the zero-degree cord has undulations forming approximately sinusoids in the reinforcement plane, as is well known in the case of protective plies used, for instance, in airplane tires.
DESCRIPTION OF THE DRAWING
The accompanying figures illustrate the invention applied to tread removal by means of a single non-undulated cord wound with zero degree.
FIG. 1 is a view showing the layers of a tire section before removal of the tread;
FIG. 2 diagrammatically shows the tread removal operation;
FIGS. 3 and 4 show what is obtained after the detachment of the tread, namely the tread (FIG. 3) and the carcass ready for recapping (FIG. 4);
FIG. 5 is a view of a precured tread, incorporating a zero-degree reinforcement, intended for subsequent use in the recapping method of the invention;
FIG. 6 is a view showing a section of the recapped tire.
DESCRIPTION OF PREFERRED EMBODIMENTS
The accompanying drawings show a tire having two side walls 3 and a tread 10, the tire being reinforced by a carcass ply 2 anchored to two bead wires 1.
There can also be noted two crown plies 4 and 5 forming with the carcass ply 2 the classical triangulated belt of most radial tires. The tire has a layer of rubber 6 covering the crown plies 4 and 5 and a zero-degree crown reinforcement produced by a single cord 7 wound from a starting point 8D on one of the shoulders of the tire across to the opposite end 8F on the other shoulder of the tire.
The zero-degree cord 7, wound continuously to form the crown reinforcement, constitutes potentially the means for separating the tread 10 (which is located above this zero-degree cord 7) from the carcass II of the tire (which is below the zero-degree cord). For the thicknesses of rubber currently present between two adjacent cords 7, the pulling force in the transverse direction, that is to say, in the direction approximately perpendicular to the initial direction of the cord, is relatively slight to the extent that it is very easy to tear off the cord manually. This operation is diagrammatically indicated in FIG. 2. On the other hand, at the level of the shoulders of the tire, the thickness of rubber present between the surface of the tire at the shoulder and the first zero-degree cord 7 may well be too great to be sheared by the pull on the cord 7. In this case, rubber is removed from a shoulder of the tire by a cutting tool until reaching the end of the zero-degree cord 7. After the removal of the tread by this method, one obtains the carcass 11 ready to be recapped, as shown in FIG. 4.
It may happen that this tread removal operation is interrupted by a cut in the cord 7. In such case, it is easy to find the new end of the cord 7 with a cutting tool before resuming the extracting thereof.
It is, of course, possible to adapt the design of the reinforcement structure of the tire to the use which is made of the zero-degree cord for the tread removal and to do this at the time of the manufacture of the new tire. In such case, the zero-degree cord will be arranged from one edge to the other, leaving the smallest possible thickness of rubber between the last cord and the surface of the tire at the shoulder. If this is not done, then, upon the recapping of said tire, after having started the removal of the tread by a machining operation, it is continued by pulling on the zero-degree cord, and the separation of tread and carcass is completed by means of a cutting tool.
In order to facilitate the use of the method of tread removal in accordance with the invention, the tire, the crown reinforcement of which contains a zero-degree cord wound from one side to the other of said crown, is characterized by the fact that the position of at least one of the ends of said cord which is arranged at zero degree is marked on the shoulder of the tire.
This marking is of very particular interest when it is possible to remove the tread completely by pulling on the zero-degree cord, which is always true when the zero-degree cord is flush with the surface of the tire at its shoulder. In order further to facilitate the extraction of the zero-degree cord, it is advantageous to mark the direction of the zero-degree winding on the shoulder of the tire. In fact, the tearing off of the cord is facilitated when the cord is inclined slightly in the direction of winding.
For the recapping of the carcasses 11, it is possible also to produce premolded annular treads the sole of which comprises, over its entire width, a zero-degree cord which is spirally arranged and embedded just below the surface of said sole. One embodiment of such annular treads consists, for instance, in applying a layer of unvulcanized rubber mix of slight thickness onto the outer surface of a cylindrical or quasi-cylindrical form, winding a single zero-degree cord on said layer from a starting point 8D on a lateral side of the layer up to the opposite end 8F on the other lateral side, putting the unvulcanized rubber mix corresponding to the tread in place, placing the said assembly in an annular sculpture mold and vulcanizing the assembly. It is advantageous to mark the position 70 (FIG. 5) and the starting direction 71 of at least one of the ends of the zero-degree cord on the lateral side of said tread. Thus, when the tread has been attached to a carcass 11 by a recapping operation, one knows the point 70 where the extraction of the zero-degree cord is to start for a subsequent tread removal operation.
A second embodiment of a zero-degree crown reinforcement suitable for the invention consists in winding a single cord 7 in two parts from the starting points 8D and 8F on the shoulders of the tire with the same direction of winding to the center of said crown of the tire.
In this case, the tread removal operation consists, simultaneously or successively, in grasping the two ends 8D and 8F and exerting a transverse pulling force until the single reinforcement cord 7 is completely extracted.
The advantage of this second embodiment of the zero-degree crown reinforcement over the first is that it permits faster removal of the tread while also being easy to carry out.
Of course, this second embodiment of a zero-degree crown reinforcement suitable for the invention can be included in the manufacture of new tires. It is then preferable to mark the two ends 8D and 8F of the two windings, as well as their common direction of winding, on the shoulders of the tires.
In the same way, it is also possible to produce premolded annular treads with the incorporation within them of a reinforcement cord wound in two parts from the two sides of the sole of the tread up to its center, marking on the side walls of said tread the starting positions of the zero-degree cord as well as the direction of winding thereof.
Prior to the present invention, prior removal of the tread and preparation of the carcass always required the use of rather expensive equipment in order to carry out a machining operation on the carcass. Due to the present invention, the prior removal of the tread of the carcass is a very easy operation. It is therefore possible to shift the recapping to the car maintenance shops. One can thus provide for very frequent tread removal and recapping, for instance when the tred pattern is more than 50% worn. It is well known that the water drainage capacity declines very greatly as the tread pattern becomes worn. One can therefore contemplate using the carcass of the tire several times and replacing the tread of the tire as frequently as necessary, for instance in order to change from a summer tread to a winter tread. | 4y
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BACKGROUND OF THE INVENTION
[0001] This Invention is a dimming adjustable discharge lamps power source device with voltage amplitude control function which is controlled by a positive or negative logic control, the high frequency transformer of the circuit gives high voltage power source and the multiple secondary of the transformer give stable DC power supply, protection, over current, over voltage, and etc. function through rectify, filtering, voltage regulator, and etc. devices, above embodiment is applied in TFT LCD TV, LCD monitor, LCD TV Wall, LCD luminance brightness control, power of PDP TV, and DC Power Supply and secures safety.
[0002] The luminance brightness control of Cold Cathode Fluorescent Lamp, CCFL, External Electrode Fluorescent Lighting, EEFL used to be Pulse Frequency Modulation, PAM, or Pulse Width Modulation, PWM methods to achieve CCFL, EEFL lamps group dimming control, the disadvantage of these methods are,
1. PFM, the amplitude is fixed, the frequency is variable, and the variable frequency causes lot of noise interference. 2. PWM, The frequency is fixed, the width of the pulse is variable, the method makes hum noise and it used to be applied to low voltage application, such as Inverter.
[0005] This Invention has a fixed frequency and pulse width; by adjust the amplitude of DC Voltage to achieve luminance brightness control, moreover it provides stable DC Power Supply to system to solve above disadvantage of PAM and PWM.
[0006] The first purpose of this Invention is to give CCFL, EEFL lamps group a fixed frequency and pulses width power source.
[0007] The second purpose of this Invention is to provide a VAM method to solve the noise, hum, and high cost of PWM and PAM methods.
[0008] The third purpose of this Invention is to provide luminance brightness control to discharge lamps of TFT LCD TV, LCD Monitor, LCD TV Wall, PDP TV, and etc monitors.
[0009] The forth purpose of this Invention is to provide a VAM method to generate a variable DC Power Supply to give other application in system.
[0010] The fifth purpose of this Invention is to provide a high frequency and high wattage output which is couple from a half bridge oscillation driver, one or multi-sets of MOSFETs, one or more output high frequency transformers to match power requirement of TFT LCD TV, LCD Monitor, LCD TV Wall, PDP TV, and etc monitors.
[0011] The sixth purpose of this Invention is to provide an impulse width control circuit to give luminance brightness control to CCFL and EEFL lamps group in or out of the glow zone and DC voltage control of the DC Power Supply. The seventh purse of this Invention is to offer better circuit to prove this embodiment.
SUMMARY OF THE INVENTION
[0000]
1. A DC output of Active Power Factor Corrector (APFC) controlled by positive or negative logic voltage, the control coupling can be photo coupling or direct coupler.
2. A high frequency high power output circuit includes a high frequency oscillation and driver circuit to give the necessaries to the primary of the high frequency transformer, the circuit can be a self oscillating half bridge driver IC circuit or a full bridge driver IC circuit depended on the requirement of the CCFL or EEFL lamps group.
3. A High Frequency High Power Output Circuit, HFHPOC, is a self oscillating half bridge driver IC, multiple sets of MOSFET, and one or multiple sets of high frequency transformer to enhance the output of the circuit.
4. A impulse width control circuit is composed by pulse width control circuit and photo coupler, the circuit controls the oscillating coefficient capacitor or output pulse width of the driver circuit of the HFHPOC to give luminance brightness control to CCFL and EEFL lamps group in or out of the glow zone and output voltage adjusting of the DC power source.
5. A high frequency transformer contains primary and multi sets of secondary; the secondary contains a high frequency high power source to give the requirement of the CCFL and EEFL lamps group, the multiple sets of secondary give different DC voltage to system.
6. CCFL and EEFL lamps group are controlled by the high frequency high power source of the secondary of the high frequency transformer, an open circuit sensor circuit is connected to each lamp to ensure the quality of backlight.
7. Each one DC source output of the secondary of the high frequency transformer contains rectifier, filtering, regulation, over current protection, over voltage protection circuit.
8. The DC source of the protection circuit gets from DC source circuit, the protection circuit works when open circuit, over voltage of CCFL and EEFL lamps group, over current, over voltage of DC power source.
9. The I/O interface device contains one or multi inputs to control the luminance dimming of CCFL and EEFL lamps group and DC source.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] As shown in FIG. 1 , the block diagram of a VAM power device includes, 100 Active Power Factor Corrector, APFC, 200 , High Frequency Power Source Circuit, 300 , High Frequency Transformer, 400 , CCFL or EEFL Lamps group, 500 , Protector. Circuit, 600 , Impulse Width Control, 700 , DC Power Source, 800 , Output/Input Interface Equipment.
[0022] As shown in FIG. 2 , an embodiment of APFC circuit, 100 , of this Invention. An Electro-Magnetic Interference Filter, EMIF, is connected to AC source, the IC 1 is an APFC IC, and pin 1 , P, is a voltage feedback. The rating of the feedback voltage is different by different IC. For example, the feedback voltage of TDA4862 is 2.5V. When the output voltage, DC V, is fixed, the rating of RA is decreased, the voltage of P is increased, and thus the DC V is decreased. To approach the purpose, a RB and a Photo Coupler Ph 1 is applied in this embodiment. RB and output part of Ph 1 is connected in serial and paralleled to RA. When switch S 1 is switched to 1 , the LED part of Ph 1 is most lit when the Vin is a high voltage, therefore; the equipotent resistance of RA and RB is lowest, and the voltage of DC V is lowest. Conversely when the Vin is a low voltage, the voltage of Vin is highest. The Vin and DC V is an inverse ratio. When S 1 is switched to 2 , the LED part of Ph 2 is most lit when the Vin is a high voltage, therefore; the equipotent resistance of RC and RD is lowest, and the voltage of DC V is highest. Conversely when the Vin is a low voltage, the voltage of Vin is lowest. The Vin and DC V is a direct proportion. Thus, the input characteristic of Ph 1 and Ph 2 is an important coefficient of the range of Vin. The range of Vin can be wide and digital controllable with combination of R 1 and R 2 . The output part of Ph 1 and Ph 2 can be photosensitive or other function type and not limited.
[0023] As shown in FIG. 3 , is the other embodiment of APFC circuit, 100 , of this Invention. Instead of Ph 1 and Ph 2 , the RA and RC can be replaced by variable resistor, VR 1 and VR 2 . The DC V can be adjusted manually.
[0024] As shown in FIG. 4 , is an embodiment of High Frequency Power Source Circuit, 200 . IC 2 is a Self Oscillating Half Bridge Driver such as IR2153, IR2155, MC34066, uC1864, and etc. The oscillating frequency is depended on the resistor RF; capacitor CF. A photo coupler Ph 3 , an ignition circuit, gives CCFL, and EEFL lamps group enough ignition energy. A photo coupler Ph 4 , a protector circuit, works when open-circuited, over current, and over voltage occurs on CCFL, and EEFL lamps group 400 or DC Power source 700 . The LED part of Ph 4 is lit, the IC 2 stop working. The pin 5 and 7 of IC 2 sends pulses to drive Power MOSFET, M 1 and M 2 . One set of Power MOSFET, M 1 and M 2 connected to the primary, connection 1 and 2 , of High Frequency Transformer, 300 , in half-bridge wiring. The harmonic frequency is depended on capacitor C and inductor L. The frequency of IC 2 is fixed, and not variable with load.
[0025] As shown in FIG. 5 , an embodiment of 400 , CCFL or EEFL Lamps group, 500 , Protector Circuit, 700 , DC Power Source. The connection 3 and 4 , one of the secondary of High Frequency Transformer 300 , is a high frequency power source of CCFL or EEFL lamps group. Each CCFL or EEFL connects to high frequency capacitor C 1 , C 2 , and a protecting detection circuit. When one or more than one CCFL or EEFL act open circuited, the signal sent to Protector Circuit is a zero voltage; thus the Protector Circuit 500 works. Ph 5 is an AC Input Response Photo Coupler. A RK is connected to input part of Ph 5 in parallel to prevent over current occurred on input part of AC Input Response Photo Coupler. The second secondary of High Frequency Transformer 300 , connection 5 , 6 , and 7 ; the third secondary of High Frequency Transformer 300 , connection 8 , 9 , and 10 ; the fourth secondary of High Frequency Transformer 300 , connection 11 , and 12 are supplementary power sources. A full-wave rectifier, a it type filter, and a Programmable Precision References IC, IC 3 , are connected to the second secondary of the high frequency transformer 300 . A photo coupler Ph 6 is set for isolation from fourth secondary to achieve purpose of regulation. Re and R 1 are for the reference voltage adjusting for IC 3 . RG and RH are for divided voltage from supplementary power source. A full-wave rectifier, a π type filter, a three terminal voltage regulator, IC 4 , are connected to the third secondary of high frequency transformer 300 . A half wave rectifier is connected to the fourth secondary of the high frequency transformer 300 . The DC voltage V 1 and V 2 are the output voltage of the second and the third secondary of high frequency transformer 300 . The forth secondary is independent power source; the function is to execute the regulation of V 1 . The rectifier, filter, and regulator circuit can be varied and depended on application. Protector Circuit, 500 , is composed by OP Amp IC, ICS and IC 6 . ICS detects CCFL or EEFL Lamps group 400 . A delay circuit is composed by ZD 1 . The delay circuit makes sure the protector signal is taken from stable CCFL or EEFL Lamps. IC 6 detects over current and over voltage of V 1 and V 2 . The over voltage detection device of V 1 is Zener diode DZ 2 , the over current detection device is resistor R 3 . The over voltage detection device of V 2 is Zener diode DZ 3 , the over current detection device is resistor R 4 . The output of ICS and IC 6 connect to connection J, also connected to J connection of High Frequency Power Source Circuit 200 . ICS and IC 6 can be two different parts in one IC.
[0026] As shown in FIG. 6 , is an embodiment example of VAM power system. Physically it is the same structure as FIG. 2 , FIG. 4 , and FIG. 5 except symbols. The only difference is the fourth secondary, connection 11 and 12 , of high frequency transformer 300 , an independent power source. The purpose of the circuit is to give a stable voltage output to DC output of the second secondary of high frequency transformer 300 . When the V 1 is low, the LED part of IC 6 is not lit, the MOSFET M 3 is on, and a setting voltage can be measured at V 1 . If the V 1 is greater than setting, the M 3 is off, and the V 1 is lower, therefore; V 1 is a very stable voltage output. IC 3 is a Programmable Precision References IC. R 5 is an over current detection resistor. The I/O Interface 800 includes 5V DC output, connection 1 , 2 , and 3 ; 12VDC output connection 9 ; ground connection 4 , 5 , 6 , and 10 ; the input connection, connection 7 is a lamination dimming control signal input, usually from 0 to 4.5 VDC or 0 to 5 VDC depended on system.
[0027] As shown in FIG. 7 , is an embodiment example of VAM power system. The DC output of APFC 100 is controlled by Programmable Precision References IC, IC 3 , of the second secondary, connection 5 , 6 , and 7 , of high frequency transformer 300 . By adjusting the DC output of APFC to control the luminance of CCFL or EEFL Lamps group. The first secondary, connection 3 , 4 , and the second secondary connection 5 , 6 , and 7 , belong to a same high frequency transformer 300 , therefore; the second secondary reacts the RMS voltage of the first secondary. The other function is as same as pervious embodiment examples. The control logic can be negative or positive logic control depended on the requirement and the characteristics of the CCFL or EEFL Lamps group and not limited.
[0028] As shown in FIG. 8 , is an embodiment example of VAM power system. The DC output of the second secondary of high frequency transformer 300 , connection 5 , 6 , and 7 , is controlled by a reference voltage control variable resistor, VR 3 , of Programmable Precision References IC, IC 3 . When the V 1 is smaller than setting voltage, Ph 1 gets a positive voltage, therefore; the DC output of the APFC 100 gains, V 1 gains to setting voltage as well. The third secondary of high frequency transformer 300 , connection 8 , 9 , and 10 , supplies V 2 to load as well. The other function is as same as pervious embodiment examples.
[0029] As shown in FIG. 9 , is an embodiment example of VAM power system. FIG. 9 (A) shows FIG. 6 , FIG. 7 , and FIG. 8 applies two sets of MOSFET in parallel to gain the output of High Frequency Power Source Circuit 200 . The purpose is to diffuse the heat dissipation and cut the thickness within same output. There is only one driver IC, IC 2 , applied in circuit to synchronize the two sets of MOSFET. FIG. 9 (B) replaces the two high frequency transformer 300 with one high frequency transformer 300 to cut the cost. The sets of the MOSFET can be multiple and not limited. FIG. 9 (C) shows the two primary shown in FIG. 9 (A) reeled in one high frequency transformer 300 to reduce the heat dissipation. That is, the High Frequency Power Source Circuit can be s self oscillating full bridge driver and not limited. The MOSFET can be replaced with IGBT or other power transistor device and not limited.
[0030] As shown in FIG. 10 , is an embodiment of Impulse Width Control circuit. The output of the Photo couplers Ph 7 and Ph 8 are connected to the Gate Terminals of M 1 and M 2 shown in FIG. 4 . A Timer IC, IC 7 , such as 555, transistor T 3 composes a Sawtooth Generator. The Sawtooth wave is sent from K to the positive input of the OPAmp IC 9 . The frequency of the Sawtooth wave is f=1/CK [0.75(R 6 +R 7 )+0.693*VR 4 ]; the value of R 6 *CM has to greater than 10*R 7 *CK. The Sawtooth Generator can be other sawtooth generator IC different from the above embodiment and not limited. The output of DC Summing Amplifier IC, IC 8 , and DC voltage is connected to the negative input of the IC 9 . The voltages of positive input of IC 8 come from DC voltage and External Control Voltage, EV. The negative input of the IC 9 is a DC voltage; the positive input of IC 9 is sawtooth wave; therefore, a pulse is generated at the output of IC 9 , Q, and the frequency of it is controlled by VR 4 . The output of the IC 9 , Q, is connected to input part of Ph 7 and Ph 8 ; the output part of Ph 7 and Ph 8 is connected to Gates of M 1 and M 2 . When the negative input of the IC 9 is large, the pulse width is narrow; therefore, the output of the high frequency transformer 300 is enlarged. Contrariwise, the output of the high frequency transformer 300 is lessened. To approach the luminance brightness control or CCFL or EEFL Lamps group, the same function IC can be applied to replace this circuit and not limited. The Impulse Width Control circuit can be applied on the luminance brightness control of other discharge lamps, such as High Pressure Sodium Lamp, HID Lamp, and etc. lamps. As shown in FIG. 11 , a real measurement wave-form from Ph 8 in FIG. 10 , the measurement takes from only one photo coupler, Ph 8 . The photo coupler Ph 7 and Ph 8 can be applied only one or both of them, depended on application. The Vin, the output, and the wave-form of the lamp is for reference and proving of this embodiment. As shown in FIG. 12 , is an embodiment of Impulse Width Control circuit. The output of Ph 8 is moved to the oscillation relation capacitor CF in parallel. The Input stays the same connection. The output frequency of IC 9 equals to the Shutdown time of the IC 2 to reach a purpose of luminance brightness control of CCFL or EEFL Lamps group. The width and frequency of output pulse of IC 9 is variable and depended on application.
[0031] As shown in FIG. 13 , is a measurement wave-form of 4 CCFL lamps applied on FIG. 12 . There is only one photo coupler Ph 8 is applied. Vin is voltage of EV in FIG. 12 ; the range is from 0 to 15V. The wave-form of voltage of control output, Ch 1 , Lamp current, Ch 2 , Vin, and the output are for reference and proving of this embodiment.
[0032] As shown in FIG. 14 , is an embodiment of DC Power Source circuit. The Programmable Precision References IC is replaced by IC 10 , OP Amp, in FIG. 5 of DC Power Source 700 . When the positive input voltage is greater than negative input voltage, a positive is sent to the LED part of the photo coupler Ph 6 , the MOSFET M 3 is off. V 1 is low down to setting voltage. When the positive input voltage is smaller than negative input voltage, the LED part of the photo coupler Ph 6 is off, the MOSFET M 3 is on. V 1 gains to setting voltage. The on/off cycles keep the V 1 in stable setting output. A negative logic can be applied on this embodiment and not limited.
[0033] As shown in FIG. 15 (A), is an embodiment of DC Power Source circuit. The photo coupler Ph 6 is replaced by a PNP transistor T 2 in FIG. 5 of DC Power Source 700 . When the source voltage of the MOSFET M 3 is higher than the setting voltage, V 1 , the IC 3 is on, T 2 is on, the gate voltage of M 3 is low, M 3 is off; the source voltage of the M 3 is low to V 1 . When the source voltage of M 3 is lower than V 1 , T 2 is off, M 3 is on; the source voltage of M 3 is high to V 1 . Due to the above movement, the V 1 is a stable output. As shown in FIG. 15 (B), is an embodiment of DC Power Source circuit. The photo coupler Ph 6 is replaced by a NPN transistor T 3 in FIG. 14 of DC Power Source 700 . The coupling way is a direct coupling which is different from photo coupling of FIG. 14 . As shown in FIG. 5 (C), is an embodiment of DC Power Source circuit. When the source voltage of M 3 is higher than setting voltage V 1 , the voltage between RE and R 1 is higher than Zener voltage of ZD 5 and the base-emitter voltage of T 4 , the T 4 is on, M 3 is off. When the source voltage of M 3 is lower than setting voltage V 1 , the M 3 is on. Due to the above movement, the V 1 is a stable output. As shown in FIG. 16 (A), is an embodiment of DC Power Source circuit. When the secondary of high frequency transformer 300 , connection 8 , in positive half wave, the LED part of Ph 9 is on; the RH is connected to the positive and the negative of the secondary, connection 11 and 12 , of the high frequency transformer 300 ; the MOSFET M 5 is off; the MOSFET M 4 is on. M 4 and M 5 have the characteristic of unidirectional; therefore, the circuit has rectifier function. When the junction B gets a rectified voltage, the V 2 gets a DC voltage after flows through a π filter circuit composed by C 3 , L 1 , and C 4 . The center junction of RE and R 1 is connected to Reference of the Programmable Precision References IC, IC 3 , the other two junctions are connected to V 2 . When the V 2 is greater than setting voltage, the IC 3 is on, both M 4 and M 5 is off, the rectifying stops, the V 2 is lower. When V 2 goes low enough to turn the IC 3 off, the M 4 and M 5 execute the rectifying function again, the V 2 voltage is greater than it was. The M 4 and M 5 have the function of rectifying and regulation. The voltage of B junction could be higher than 8 and 10 connection of high frequency transformer 300 any time, to avoid this; a Protect opposite current detection circuit is applied in this invention. When the positive input of IC 11 is greater than the negative one, the LED part of Ph 12 is lit, the output of Ph 12 is on, the power source is cut off, the emitter of the T 4 is a zero voltage output, M 4 and M 5 cut off; therefore, no reversing voltage occurs on high frequency transformer 300 . The D 3 and D 4 are diodes; they are set to give the instant voltage comes from connection 8 and 10 to the negative input of IC 11 . RL and RM are for setting voltage of positive input of IC 11 . The RN and RP are for setting voltage of negative input of IC 11 .
[0034] As shown in FIG. 16 (B), is an embodiment of DC Power Source circuit with self starting function. When the positive half wave occurs on connection 8 of high frequency transformer 300 , the sum of Zener voltage of DZ 7 , the forward bias voltage of D 1 , and the forward bias voltage of LED part of Ph 9 has to be greater than voltage of junction B; then the circuit has the function of protect opposite current. If the voltage is greater than voltage of junction B, the LED part of Ph 9 is lit, the output of the Ph 9 is on, the positive voltage comes from connection 11 and 12 is on RH, M 4 is on, the positive half wave voltage goes through M 4 to the π filter composed by C 3 , L 1 , and C 4 ; then it becomes to output voltage V 2 . When the positive half wave occurs on connection 10 of high frequency transformer 300 , the execution is the same as the above. Both positive half wave of 8 and 10 are connected to junction B, thus is a full-wave rectifier. IC 3 , Programmable Precision References IC, is on, the output of the Ph 6 is on, the gates of M 4 and M 5 is shorten, the V 2 is lower than it was; when V 2 drops until the IC 3 is off, the M 4 and M 5 executes rectifying, the V 2 is higher than it was. Instead of the Protect opposite current detection circuit, DZ 7 and DZ 8 can be removed out of the circuit. The M 4 and M 5 has characteristic of bidirectional; therefore, the Drain and source can be switch from each other and not limited, the gate circuit stays the same.
[0035] As shown in FIG. 16 (C), is an embodiment of DC Power Source circuit with self starting function. When the positive half wave occurs on connection 8 of high frequency transformer 300 , the sum of Zener voltage of DZ 7 , the forward bias voltage of D 1 , and the base voltage of T 5 has to be greater than voltage of junction B; then the circuit has the function of protect opposite current. If the voltage is greater than voltage of junction B, T 5 is on, the positive voltage comes from connection 11 and 12 is on RH, M 4 is on, the positive half wave voltage goes through M 4 to the π filter composed by C 3 , L 1 , and C 4 ; then it becomes to output voltage V 2 . When the positive half wave occurs on connection 10 of high frequency transformer 300 , the execution is the same as the above. Both positive half wave of 8 and 10 are connected to junction B, thus is a full-wave rectifier. IC 3 , Programmable Precision References IC, is on, the output of the Ph 6 is on, the gates of M 4 and M 5 is shorten, the V 2 is lower than it was; when V 2 drops until the IC 3 is off, the M 4 and M 5 executes rectifying, the V 2 is higher than it was. The Power MOSFETs M 4 and M 5 have the function of rectifying and regulation. The sources of the MOSFETs are connected to the AC terminal in this circuit.
[0036] As shown in FIG. 16 (D), is an embodiment of DC Power Source circuit with self starting function. The Ph 6 in FIG. 16 (C) is replaced with Zener Diode ZD 5 and the PNP transistor T 4 . When the V 2 is greater than the setting voltage, the IC 3 , Programmable Precision References IC works, the base of T 4 is low voltage, the T 4 is off, the gates of M 4 and M 5 are grounded; M 4 and M 5 stop rectifying, the V 2 is dropped. When V 2 is dropped to turn the IC 3 off, the M 4 and M 5 start rectifying; V 2 rises. The Power MOSFETs M 4 and M 5 have the function of rectifying and regulation. The M 4 and M 5 has characteristic of bidirectional. The sources of the MOSFETs are connected to the AC terminal in this circuit. The Protect opposite current circuit is composed by Diodes D 1 and D 2 , Zener Diodes DZ 7 and DZ 8 , current limit resistors R 8 and R 9 , base resistor R 10 and R 11 , and PNP transistors T 5 and T 6 or same function MOSFETs. The Zener Voltage of ZD 7 and ZD 8 have to be equal or greater than DC output to prevent the opposite current and energy wasting. The Protect opposite current circuit of FIG. 16 (C) is same function as above. The M 4 and M 5 in FIG. 16 (A), (B), (C), and (D) can be a rectifier and has the characteristic of low losses and substitutes rectifier Diodes. Ensemble with FIG. 5 and the DC power source 700 in FIG. ( 14 ) is a very practical application for industry.
[0037] As shown in FIG. 17 , is an embodiment of DC Power Source circuit. This circuit is composed by FIG. 4 , FIG. 8 , and FIG. 16 . The frequency of IC 2 is related to RF and CF. When self oscillating half bridge driver IC 2 working, the connection 5 , 6 , and 7 generates a high frequency voltage, after full wave rectifying and filtering, a setting voltage is got from the center junction of RE and RI. When the setting voltage is greater than 2.5V, Programmable Precision References IC 3 is on, LED part of Ph 6 is lit, the sum of RJ and RK is drop, the oscillating frequency is higher, the output voltage of secondary of high frequency transformer 300 is lower, the DC output voltage is lower. When the DC output is lower than setting voltage, the oscillating frequency of the IC 3 is lower, the DC output is greater; therefore, the DC output becomes stable. The secondary connection 8 , 9 , and 10 ; secondary connection 5 , 6 , and 7 belong to same high frequency transformer 300 ; therefore, the DC output of connection 8 , 9 , and 10 is affected by DC output of connection 5 , 6 , and 7 ; this circuit gets stable DC output and against the affection of impulse width control circuit 600 . The control logic of this circuit can be positive and negative logic depended on application and L C harmonic curve and not limited.
[0038] This Invention is a power source device with VAM control method; an APFC circuit which the DC output is controlled by positive and negative logic control, by controlling the amplitude of the high frequency power source to achieve the luminance brightness control of CCFL or EEFL lamps group; a impulse width control to achieve luminance brightness control of CCFL or EEFL lamps group; simultaneously get a high frequency output, multiple sets of stable DC output from secondary; function of protect circuit includes open-circuited of discharge lamp, over current, over voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] FIG. 1 , the block diagram of a VAM power device
[0040] FIG. 2 , an embodiment of APFC circuit
[0041] FIG. 3 , an embodiment of APFC circuit
[0042] FIG. 4 , an embodiment of High Frequency Power Source Circuit
[0043] FIG. 5 , an embodiment of CCFL or EEFL Lamps group, DC Power Source, and Protector Circuit
[0044] FIG. 6 , an embodiment of VAM power system
[0045] FIG. 7 , an embodiment of VAM power system
[0046] FIG. 8 , an embodiment of VAM power system
[0047] FIG. 9 , an embodiment of VAM power system
[0048] FIG. 10 , an embodiment of Impulse Width Control circuit
[0049] FIG. 11 , a measurement wave-form of 4 CCFL lamps applied on FIG. 10
[0050] FIG. 12 , an embodiment of Impulse Width Control circuit
[0051] FIG. 13 , a measurement wave-form of 4 CCFL lamps applied on FIG. 12
[0052] FIG. 14 , an embodiment of DC Power Source circuit
[0053] FIG. 15 , an embodiment of DC Power Source circuit
[0054] FIG. 16 , an embodiment of DC Power Source circuit
[0055] FIG. 17 , an embodiment of DC Power Source circuit | 4y
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This is a continuation in part application of application Ser. No. 18,535, filed Mar. 8, 1979, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to liquid compositions of anesthetic agents in aerosol containers. More specifically, this invention relates to liquid compositions of the anesthetic benzocaine which form single phase mixtures in combination with solvent and hydrocarbon propellants, and which remain single phase at low temperatures and high concentrations of benzocaine.
2. Description of Related Art
Benzocaine, the ethyl ester, ester of p-aminobenzoic acid, is a well known local anesthetic which has been topically administered in the form of ointments, lotions, sprays, gels and as an impregnant in first aid pads. In order to enhance or prolong benzocaine's anesthetic activity, various efforts have been made to increase the concentration of benzocaine in various solvents or to more effectively maintain the anesthetic at its site of administration. Increasing the concentration of benzocaine, however, had to be balanced against the increasing probability of benzocaine precipitation, particularly at colder temperatures, thereby limiting their field of use. The goal of formulating highly concentrated benzocaine compositions characterized by cold temperature resistance is even greater in aerosol anesthetic compositions wherein even small amounts of precipitate can clog valves or orifices, and wherein sufficient pressure must be maintained to both completely deliver all the benzocaine solution within the container and evenly distribute the benzocaine solution with desirable spray characteristics.
Many solvents have been disclosed for benzocaine. For example, U.S. Pat. No. 2,187,597 discloses anesthetic formulations containing up to five percent of the anesthetic agent in a mixture of benzyl alcohol and ethyl chloride. Other formulations containing up to 10% benzocaine in mixtures with a procaine salt, water, water miscible poly-hydroxy aliphathic alcohols and their ethers have been disclosed in U.S. Pat. No. 2,382,546. U.S. Pat. No. 2,457,188 discloses benzocaine solutions containing at least 10% benzocaine at 20° C. utilizing solvents selected from certain polyoxyalkylene glycols, aliphatic ethers of dihydric alcohols, aromatic ethers of aliphatic dihydric alcohols, carboxylic acid esters of aliphatic dihydric alcohols, and carboxylic acid esters of aromatic and aliphatic ethers of aliphatic dihydric alcohols. In U.S. Pat. No. 2,682,182, benzocaine solutions containing up to 16% benzocaine at 0° C. were disclosed in a mixture employing a major amount of propylene glycol and a polyoxyethylene (8-25) hexitan monolaurate.
Anesthetic aerosol preparations containing at least 10% benzocaine in diesters of C 8 -C 12 carboxylic acids and polyethylene glycols having a molecular weight of appoximately 300-600, and a propellant system made from mixture of chlorofluorohydrocarbons have been disclosed in U.S. Pat. No. 3,322,634. These aerosol formulations, however, are no longer acceptable because of certain atmospheric effects associated with chlorofluorohydrocarbons.
Benzocaine has also been employed in formulations containing certain other therapeutic ingredients, for example, as disclosed in U.S. Pat. No. 3,808,319 wherein the solvent is volatile alcohol such as ethyl alcohol or isopropyl alcohol. Solvents of this type, however, are generally counterproductive to desirable anesthetic properties because of their stinging nature to sensitive or wounded skin and the like. Compositions containing up to 15% benzocaine are further disclosed in U.S. Pat. No. 4,052,513 in the form of oil in water emulsions.
SUMMARY OF THE INVENTION
This invention provides liquid anesthetic compositions in aerosol containers. The composition of this invention comprises a single phase mixture of a water washable base of the preferred anesthetic benzocaine in a solvent and a propellant.
The weight percent of the benzocaine in the solvent is from about 0.5% up to its maximum solubility in the solvent. Selection of the solvent is made from the group consisting of polyoxyethylene sorbitan trioleate having an average of about 20 units of ethylene oxide in the molecule polyethylene glycol monolaurate wherein the polyethylene glycol has an average molecular weight of about 200 to about 600 and mixtures thereof. The propellant of the compositions of this invention comprises a mixture of difluoroethane and a hydrocarbon selected from the group consisting of n-butane, iso-butane and n-propane.
This invention is further defined by the provision that the composition is a single phase mixture after exposure to temperatures of about -20° C. when the benzocaine comprises about 20% by weight of the water washable base of benzocaine and solvent.
While the invention is illustrated with the anesthetic benzocaine, it will be apparent to those skilled in the art that the composistion of this invention is also suitable for other therapeutic agents deliverable from aerosol containers in which water washability, single phase cold temperature resistance and nonstinging of solvents are desirable characteristics.
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to liquid anesthetic compositions in aerosol containers comprising a single phase mixture of a water washable base of benzocaine in a solvent and a propellant. The weight percent of benzocaine in the water washable base is from about 0.5% up to its maximum solubility in the solvent. For most effective anesthetic properties, the benzocaine comprises at least 10% by weight of the base and preferred compositions contain about 20% by weight of benzocaine.
Solvents useful in this invention are selected from the group consisting of polyoxyethylene sorbitan trioleate having an average of about 20 units of ethylene oxide in the molecule polyethylene glycol monolaurate wherein the polyethylene glycol preferably has an average molecular weight of about 400, and mixtures thereof. Although wider ranges of one solvent to another are acceptable, the solvent is preferably a mixture of the herein listed solvents in a ratio of 40:60 to each other, and most desirably in a ratio of 50:50.
The propellant system comprises a mixture of difluoroethane and a hydrocarbon selected from the group consisting of n-butane, isobutane and n-propane. In the preferred system which utilized n-butane, the difluoroethane comprises about 35-70% by weight of the propellant system. In the most preferred embodiments each of the propellants in a two propellant system comprise about 50% of the total propellant.
Further, the water washable base of benzocaine in solvent and the propellant each comprises about 45% to about 55% by weight of the liquid anesthetic composition, and in preferred embodiments, about 50%.
The compositions of this invention are further defined by the provision that the compositions form a single phase, clear liquid solution following exposure to temperatures of -20° C, when the benzocaine comprises about 20% of said water washable base, and in preferred embodiments, the composition is a single phase mixture at about -20° C. Compositions having the most preferred single phase characteristics at -20 ° C. employ the polyethyleneglycol monolaurate, or mixtures of polyoxyethylene sorbitan trioleate with the polyethyleneglycol monolaurate as the solvent.
In formulating the composition of this invention, other ingredients, such as antipruritic agents, anit-infectives, anti-fungal agents and anti-bacterial agents are typically incorporated.
The following composition is an illustration of a preferred embodiment of this invention:
______________________________________Water Washable Base______________________________________Benzocaine 200.0 gMenthol 5.0 gMethylparaben 10.0 gPolyoxyethylene 20 Sorbitan Trioleate 392.5 gPolyethyleneglycol 400 Monolaurate 392.5 g______________________________________
The composition of the invention may be prepared by charging the solvent into a suitable container equipped with a stirrer, adding the benzocaine and/or other active ingredients and mixing until dissolution. The solution is then filtered through a suitable screen and loaded into an aerosol container along with the propellants in a conventional manner.
A suitable container for the composition of this invention is a can having a "2P" rating as specified by the United States Department of Transportation. Among the valve systems which have been employed satisfactorily in any position are those similar to a Seaquist NS-36 or NS-34 (Seaquist Valve Co., Cary, Ill.) or those similar to ARC-KN-37 (Ethyl Products Co., North Riverside, Ill.).
The invention is further illustrated by the following examples:
The following bulk concentrates (water washable base of benzocaine in solvent) were prepared for further evaluation,
______________________________________ BULK CONCENTRATES I II______________________________________Benzocaine 20% 20%Menthol 0.5% 0.5%Methylparaben 1.0% 1.0%Polyoxyethylene 20 78.5% --Sorbitan TrioleatePEG 400 Monolaurate -- 78.5%______________________________________
__________________________________________________________________________ExampleBulk Concentrates Propellants Pressure Physical Stability# I II difluoroethane n-butane psig @ 70° F. RT -20° C. (for 1__________________________________________________________________________ day)1. 25% 25% 25% 25% 57 OK* OK2. 22.5% 22.5% 27.5% 27.5% 71** OK OK3. 27.5% 27.5% 22.5% 22.5% 71** OK OK4. -- 50% 35% 15% -- OK OK5. -- 50% 30% 20% 57 OK ppt. OK @ RT6. -- 50% 25% 25% 56 OK ppt. OK @ RT7. -- 50% 20% 30% 51 OK ppt. OK @ RT8. 25% 25% 35% 15% 63 OK OK9. 10% 40% 30% 20% 60 OK OK10. 25% 25% 30% 20% 58 OK OK11. 25% 25% 25% 25% 57 OK OK12. 25% 25% 20% 30% 52 OK OK13. 25% 25% 15% 35% -- Separation --14. 25% 25% 18% 32% -- OK OK15. 25% 25% 25% 25% 57 OK OK16. 20% 30% 25% 25% 79** OK OK17. 30% 20% 25% 25% 78** OK OK__________________________________________________________________________ *One phase system, clear solution **Measured at RT | 4y
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BACKGROUND OF THE INVENTION
Avalanche diodes, which are sometimes loosely referred to as Zener diodes are commonly used for providing a reference voltages for analog circuits. One particular application is as part of an ESD protection clamp.
An important consideration in designing semiconductor circuits, however, is the need to avoid introducing special process steps that would increase the overall cost. Thus it is desirable to be able to include so-called free structures by making use of existing process steps. In a CMOS process, however, only limited variations can be made to available regions in order to form diodes. For instance, diodes can be created using n+/p-well, p+/n-well, p-well/n-well, and, to some extent, n+/p+ junctions by spacing the n+ and p+ regions far apart to avoid tunneling. In a 0.18 um process these combinations typically provide breakdown voltages of approximately 12V, 12V, 17V, and 4V, respectively. As a result avalanche diodes are available only with discrete breakdown voltage values.
In the case of power supply electrostatic discharge protection (ESD) clamps, breakdown voltages in the range of about 5V–10V are, however, required. Conventional diodes thus fail to provide the requisite breakdown voltages.
One proposed prior art solution is to make use of n+/p+ as the diode and make use of a blocked space such as a shallow trench isolation region (STI) 100 between the n+ region 102 and p+ region 104 as shown in FIG. 1 . However, this is usually not possible, especially in the case of small dimension devices, due to inadequate tolerance in the mask alignment.
The present invention seeks to address the problem of providing suitable breakdown voltages for avalanche diodes without adding additional process steps to the CMOS process.
SUMMARY OF THE INVENTION
The present invention comprises an avalanche diode structure, wherein the structure is adjustable to provide for a wide range of breakdown voltages. In particular, by adjusting the blocking junction, different breakdown voltages can be realized. This is achieved by forming n+ and p+ regions and making use of a polygate in a CMOS process to form an abrupt junction. The gate can, further, be provided with a contact and its voltage adjusted. For instance, the gate can be connected to the cathode or anode or to an external bias circuit to adjust the breakdown voltage.
Thus, according to the invention, there is provided an avalanche diode structure comprising a p+ and a n+ region under a polysilicon region. For ease of description, the polysilicon region will be referred to as a polygate since it is formed in a CMOS process in the same way as any other polygate would be formed. However, the polygate of the present diode structure need not necessarily be provided with a contact.
The p+ and n+ regions are typically formed in lightly doped regions, referred to as PLDD (p-lightly doped region) and NLDD (n-lightly doped region), respectively.
Further, according to the invention, there is provided a method of forming an avalanche diode, comprising providing a polygate and using the polygate as a self aligned mask during doping of the p-n junction of the diode. The masks for the oppositely doped regions of the junction are preferably positioned so as to overlap with the polygate. Preferably the doping of the p-n junction comprises forming n+ and p+ regions in corresponding lightly doped regions. The lightly doped regions are preferably formed during a high voltage portion of the CMOS process. The method may include adjusting the gate length.
The invention, further, provides for adjustment of the breakdown voltage of an avalanche diode of the invention by suitably biasing the polygate. The gate may be connected to either the anode or the cathode of the diode structure, or may be connected to a driver circuit that biases the polygate to provide dynamic breakdown voltage control.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross section through a prior art avalanche diode;
FIG. 2 shows a cross section through one embodiment of the invention;
FIG. 3 shows a cross section through another embodiment of the invention;
FIG. 4 shows graphs of drain current against source-drain voltage for different gate lengths, and
FIG. 5 shows graphs of drain current against source-drain voltage for different gate bias.
DETAILED DESCRIPTION OF THE INVENTION
One embodiment of the invention is shown in FIG. 2 which shows the p-n junction of the diode 200 formed between a p+ region 210 formed in a lightly doped region 212 referred to as a p-lightly doped drain (PLDD), and a n+ region 220 formed in a lightly doped region 222 referred to as a n-lightly doped drain (NLDD).
The need for the PLDD and NLDD regions 212 , 222 can be ascribed to the CMOS process. In order to avoid contamination across the junction during the high doping process, the formation of the p+ and n+ regions 210 , 220 is typically preceded by the formation of lightly doped regions, referred to as PLDD (p-lightly doped region) and NLDD (n-lightly doped region), respectively.
As is evident from FIG. 2 , a polygate 230 is formed over the region where the p-n junction will be located. The polygate 230 has a self aligning mask function. Even though separate masks are used during the doping of the p+ and PLDD and n+ and NLDD regions, it becomes difficult to properly align them, especially at small dimensions. By making use of the polygate as a mask, the exact alignment of the masks is no longer critical. The masks for the oppositely doped regions (not shown) applied to the opposite sides of the polygate 230 , are preferably positioned so as to overlap with the polygate 230 , using the polygate 230 as a mask that provides a certain amount of self-alignment.
In one embodiment the lightly doped regions, PLDD 212 and NLDD 222 are formed during a high voltage portion of the CMOS process to provide for greater flexibility in achieving the desired breakdown voltage. A typical semiconductor circuit may include a core and an I/O structure. These two portions typically operate at different voltages. The core typically operates at a lower voltage dictated by the process, e.g. for a 0.18 μm process the voltage is 1.8V±10%, while the I/O structure may operate at a higher voltage of 3.3V or 5V. For a 0.25 μm process the core voltage is 2.5V±10%, while the I/O voltage will again be at a higher voltage of 3.3V or 5V. These different portions will be implemented by varying the process steps in order to accommodate the low and high voltage levels, respectively. For instance, in the case of a high voltage structure, the gate oxide has to be thicker and is typically implemented by making use of a dual or triple oxide. For example in the case of a 0.18 μm process, the gate oxide for the low voltage part has a length of 0.18 μm and a thickness of 30 Å, while the gate oxide for the high voltage part has a length of 0.35–0.4 μm and a thickness of 70 Å. Also, the doped regions will be adapted to the different operating voltage. During a high voltage process, more dopant extends under the gate from either side of the gate 230 . Thus, for example in a 0.18 μm process, a junction width between the p+ and n+ regions 210 , 220 of approximately 0.15 μm is achieved even with a polygate length of 0.35 um. In contrast, for a low voltage implantation in a 0.18 μm process the junction width will remain rather large (approximately 0.1 μm) even with a polygate length of only 0.18 μm.
Thus by reducing the length of the polygate in a high voltage process, smaller distances and even overlaps between the PLDD and NLDD can be achieved.
This provides an abrupt junction with minimum breakdown voltage of approximately 5V in a 0.18 um process. On the other hand, the gate length can be increased to provide for a more gradual doping distribution near the p-n junction region. This allows the breakdown voltage to be increased up to the well-to-well breakdown voltage level. Thus, the invention provides an avalanche diode structure for which the breakdown voltage can be adjusted in relation to the polygate length. In other embodiments, the PLDD and NLDD regions were formed during a high voltage portion of the process, while the polygate was formed during a low voltage portion of the process. Other embodiments formed some of the doped regions (n+, p+, NLDD, PLDD, n-well, p-well) during a high voltage portion of the process and others during a low voltage portion. Thus, for example the PLDD may have been formed during a low voltage portion of the process, while the NLDD was formed during a high voltage portion of the process.
The effect of gate length changes is illustrated by the graphs of FIG. 4 , which show TCAD analyses for different gate lengths for diodes of the invention. In particular, FIG. 4 shows curves of drain current against source-drain voltage for different gate lengths, while biasing the gate to a voltage of 1V. Curve 400 shows the current voltage curves for a 0.1 μm gate length, curve 402 shows the curves at a polygate length of 0.5 μm, and curve 404 shows the curve for a polygate length of 0.8 μm. Thus, it is clear that the breakdown voltage can be reduced by reducing the polygate length of the diode. For instance, in the embodiment of FIG. 2 , the polygate length is reduced or increased to provide for breakdown voltages as low as approximately 5V.
Another embodiment of the invention is shown in FIG. 3 which shows the p+ region 310 and PLDD 312 formed in a p-well 340 , while the n+ region 320 and NLDD 322 are formed in a n-well 350 . In this embodiment the junction between the p-well 340 and n-well 350 is located under the polygate 330 . However the junction could be shifted to the left or the right. Thus the FIG. 2 embodiment can be seen as the extreme case where the junction has been moved all the way to the left so that the n-well covers both the cathode and the anode regions, and the p-well is eliminated altogether. Simulation results show that increasing the gate length of the polygate 330 allows breakdown voltages of up to the well to well breakdown voltage to be achieved. It will be appreciated that where the p-well is eliminated altogether the upper limit to the breakdown voltage will be the breakdown voltage of the PLDD-n-well junction. Below some critical gate length the breakdown voltage will essentially be a function of the polygate length. As mentioned above, reducing the polygate length allows breakdown voltages to be reduced to approximately 5V.
The invention, further, provides for adjustment of the breakdown voltage by suitably biasing the polygate. In one embodiment the gate is connected to either the anode or the cathode of the diode structure to act as a field electrode. This allows the breakdown voltage to be further decreased or increased.
In another embodiment the polygate is connected to a driver circuit that biases the polygate to provide dynamic breakdown voltage control. This, in turn, allows the triggering of the diode to be controlled.
The effect of changing the gate bias on the breakdown voltage is shown in FIG. 5 . FIG. 5 shows TCAD analyses of different devices of the present invention, showing the effect of changing the polygate bias. Curves 500 – 506 show drain current against source-drain voltage curves for a gate length of 0.8 μm. In curve 500 the polygate is biased to a voltage of −5V; in curve 502 the gate bias is −1V; in curve 504 the gate bias is 0V, and in curve 506 the gate bias is 1V. Thus, it can be seen that the breakdown voltage can be increased by increasing the bias of the gate.
While the invention has been described with respect to a few specific embodiments, it will be appreciated that different configurations could be provided without departing from the scope of the invention. | 4y
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TECHNICAL FIELD
[0001] The present invention relates to a filter element, in particular, for use as an air filter, and a filter system having such a filter element.
BACKGROUND OF THE INVENTION
[0002] A filter element for a fuel cell is known from the publication EP 1349 638 B1 in which activated carbon is used as an adsorbing filter medium. For example, a bed of activated carbon in a cylindrical filter is proposed. The filter element is connected upstream of a fuel cell and is used to clean the cathode air.
[0003] An object of the present invention is to create a robust filter element, in particular, for filtering air.
[0004] A further object of the present invention is to provide a filter system having such a filter element.
[0005] According to one aspect of the present invention, the previously mentioned objects are achieved by a filter element having a filter body, which has, at least in sections, a wound layer having at least one adsorbent, as well as, according to another aspect of the present invention, a filter system having such a filter element.
[0006] Advantageous embodiments and advantages of the present invention result from the additional claims, the description and the drawings.
SUMMARY OF THE INVENTION
[0007] A filter element is proposed which has a filter body having a closed outer face, which surrounds a closed inner face, and the inner face encloses a central flow chamber, and at least one filter medium is situated between the outer face and the inner face, and the filter body includes, at least in sections, a wound layer having at least one adsorbent.
[0008] Advantageously, wrapped layers or wound layers not having separate creases, such as they occur in pleated filter bodies or when using embossed filter media, or defined flow channels, are designed to facilitate the manufacturing and handling of the filter elements. The filter element does not require a mutual closure of the air ducts, facilitating the manufacturing. Conventional filter elements having filter bodies made out of pleated filter media do not provide, based on the high flow speed, the required contact time ensuring a reliable adsorption or absorption of contaminants into the filter, which is critical for the functionality of a filter for gas purification or filtration efficiency and/or adsorption efficiency. In particular, this applies to filter elements having a high flow rate of the medium to be filtered, for example, in fuel cell systems, particularly in fuel cell systems of higher power classes, for example, motor vehicles or stationary applications. The design having wound layers provides the filter element with a sufficiently high contact time of the medium to be filtered with the adsorbent which, in this instance, may clean the medium to be filtered.
[0009] In addition to the thickness of the winding, that is, the filter element, resulting from the number of wound layers in the filter element and the thickness per wound layer, the shape of the winding filter is also variable. In addition to the conventional circular shape, other cross sections, such as elliptical, rectangular or polygonal shapes are also possible. These shapes may easily be produced by unwinding a flat carrier body onto a suitable inner core. In doing so, an optimal use of the installation space is provided.
[0010] The design of the filter element is uncomplicated and robust and enables long service life during use. Furthermore, filter characteristics, for example, through a targeted distribution of additional components, may be specified in the at least one wound layer in the radial and/or also in the axial direction of the filter element.
[0011] In particular, the filter element may be an air filter element.
[0012] The at least one adsorbent may include at least one material from the group of activated carbon, zeolites, silica gels, metal oxides, molecular sieves, phyllosilicates and nanoclays.
[0013] In general, adsorbent layers regarding the material selection (for example, activated carbon type, zeolites, silica gels, metal oxides such as aluminum oxide, copper oxide or manganese oxide, molecular sieves such as MOFs (MOF=metal organic framework), phyllosilicates, and nanoclays) and/or their weight per unit area may be chosen to realize a specific adaptation to the adsorption task. Nano particles made out of mineral sheet silicates are referred to as nanoclays.
[0014] An appropriate surface weight range per wound layer is between at least 10 g/m 2 to 4000 g/m 2 , preferably between at least 100 g/m 2 to 2000 g/m 2 .
[0015] According to an advantageous further refinement, the filter body may include a carrier body, upon which a layer having at least one adsorbent is applied, and by winding the carrier body, for example, onto a suitable inner core having the desired diameter and desired cross section, it may retain its form, for example, by winding onto a cylindrical inner core having a circular cross section. In doing so, the carrier body may, for immobilizing the adsorbent, be made up, for example, of two layers of band-shaped carrier material between which an adsorbent layer is situated, or also of a single layer of band-shaped material on which the adsorbent may be immobilized in an appropriate manner. In this instance, the immobilization of the at least one adsorbent may be carried out in different ways, for example, by embedding into an adhesive, contacting with adhesive thread, adhesive dots, adhesive foils and the like.
[0016] The adsorbent may be used in any form, for example, as an arbitrarily shaped granulate, a defined formed granulate (in spherical form, rod shape, etc.), a powder or the like. Likewise, the at least one adsorbent may be appropriately impregnated and/or mixed with other adsorbents and/or absorbents to, for example, read out and/or neutralize and/or relocate undesirable, chemical components from the medium to be filtered. In this instance, respective components may be distributed in an appropriate manner onto the carrier body before winding so that after the winding, for example, a plurality of layers specifically include a first component, followed by a further wound layer having different or additional components, or the distribution may be selected so that a gradient results in the radial direction in the filter element by one or a plurality of components.
[0017] In particular, at least two adsorbents and/or absorbents may be applied one after the other and, for this reason, a different adsorbent or absorbent is situated in the radially seen inner region of the winding (for example, across a few layers) than in the radially seen outer region of the winding. In this instance, it is not mandatory that the adsorbents or absorbents are applied to the same or to a one-piece carrier body and/or cover medium.
[0018] The winding may be designed in such a manner that wound layers having different surface weight ranges are radially following in sequence to achieve a desired adsorption effect. In doing so, for a, for example, specified target gas, which is obtained as a filtered medium on the clean side, a clearly specified amount of optimized adsorbent (impregnated activated carbon, zeolite, silica gel, metal oxide such as aluminum oxide, copper oxide, manganese oxide, molecular sieves such as MOFs, phyllosilicates, and nanoclays) may be used in one wound layer. In contrast to a classic adsorbent bed or an adsorbent foam, for example, an activated carbon foam, a defined position on the inflow side and/or the outflow side of such a wound layer is realized. The targeted positioning of defined adsorbent layers enables to react to situations in which specific gas molecules are preferably absorbed on the inflow side and other gas molecules preferably on the outflow side.
[0019] A single adsorbent layer may also be realized from mixtures of various adsorbents (for example, different impregnated activated carbons, zeolites, silica gels, metal oxides such as aluminum, copper, or manganese oxide, molecular sieves such as MOFs, phyllosilicates, and nanoclays).
[0020] The carrier body is intended to immobilize component particles, for example, adsorbent particles, and to stabilize the winding structure of the filter element. For example, a nonwoven fabric is well suited for this purpose. Advantageously, such nonwoven fabric layers may also take over a part of the particle filtration. For higher particle separation efficiency from the medium to be filtered and dust retention capacities, it is useful to specifically implement the carrier body in the winding as a particulate filter layer. Instead of spunbonded fabrics, fine fiber layers (for example, so called meltblown fabrics) or microfiber and nanofiber layers (for example, manufactured by way of electrospinning) may be used for this purpose. The particulate filter layer in itself may be made up of a plurality of nonwoven fabric layers or fiber layers. These particulate filter layers may be used in the winding on the inflow and/or outflow side and/or as a carrier body for the adsorbent as intermediate layers between the adsorbent layers.
[0021] Furthermore, combining the wound carrier and adsorbent layers with an additional particulate filter element (in particular, when pleated) is possible.
[0022] By implementing, for example, nonwoven fabric layers as a particle filtering layer and as a carrier body for the adsorbents, a particle separator may be integrated into the wound layer arrangement. Alternatively or additionally, further filter elements having additional functions may be coupled at an inner face and/or outer face of the filter bodies, for example, as a coating over the inner face and/or the outer face.
[0023] In this instance, the wound layers having at least one adsorbent may be structured in the following advantageous versions:
a. A carrier body having one adsorbent of a specific type, for example of a specific activated carbon type, and a cover medium to cover the one adsorbent; b. The carrier body having a mixture of adsorbents from a plurality of different adsorbent types, for example, a plurality of active carbon types, and a cover medium to cover the adsorbents; c. The carrier body having at least two layers of different adsorbents and a cover medium to cover the adsorbents; d. One of the versions a through c without a cover medium to cover the adsorbents; e. One of the versions a through c with or without a cover medium to cover an adsorbent, for example, activated carbon, with other adsorbents and/or absorbents, for example, molecular sieves and the like. This arrangement results, in the cross sections of the winding, in permanently changing adsorbent layers or absorbent layers having different characteristics, which may be customized as needed when manufacturing the filter element.
[0029] According to an advantageous further refinement, the wound adsorbent layer may have a sealing at its edges. In this instance, the sealing of the longitudinal edges of the carrier body may form an end plate located at the end face. This end plate may be already formed when winding the carrier body. In this way, a sealing via a closure element may be carried out along the longitudinal extension of the carrier body at both lateral ends of the flat layer. For example, a closure element may be formed by an adhesive, a foam, a thermoplastic, a clamp, a welding process or a combination of the aforementioned possibilities. The use of a hot melt adhesive during the winding process is also conceivable if the subsequent wound layer winds onto the previous wound layer and the hot melt adhesive is still sufficiently liquid in the peripheral area to sealingly connect to the adhesive of the previous wound layer.
[0030] The sealing at the end faces of the filter element may also occur by a retroactive, thermoplastic deformation in that a sealing element is melted and deformed onto the respective end face. The melting may be carried out by ultrasound, heating mirrors, infrared rays and hot air and the deformation by pressing the sealing element onto the end face and over its outer edge.
[0031] As a further option, a separate end disk may be used, as they are known from oil or fuel cell filter elements.
[0032] A sealing of the ends of the carrier body, that is, of the axial edges of the first and/or last wound layer in the wound-up state, may also be carried out by the methods listed above. In doing so, the flow around the at least one adsorbent in the wound layers of the filter element may be ensured and leakages may be prevented.
[0033] Appropriately, the end areas of the wound layers may be fixed at the outer shell and/or inner shell of the wound-up filter element. The fixing may be designed over a length and/or width of a few millimeters, preferably approximately 5 millimeters, to a plurality of centimeters. The fixing may be carried out by adhesion of the outermost and/or innermost wound layer onto the wound layer situated below and fixed by way of sealing, or by additional fixing elements such as glue, fixing nets, fixing lattices, elastic bands, a cylindrical element permeable for the medium to be filtered (for example, a lattice, filter material or porous solid material), clamps or fibers integrated into the wound layer, wires, etc., which then in their extension are wrapped at least once completely around the entire winding of the filter body and having the wound layers (filter layer or fiber wire layer) situated underneath. This may be carried out, for example, by welding, adhesion, interlacing, sewing, etc.
[0034] According to an advantageous further refinement, the filter body may be fluidly coupled to at least one particulate filter. Alternatively or additionally, the filter body may be fluidly coupled to at least one aerosol filter. These may be exchanged independently from the filter element in a filter system.
[0035] For separating particles, for example, a particle separator medium may, in this instance, be applied onto the surface shell of the winding in form of a flat layer or as a folded, in particular, pleated design, which optionally may be provided with the same seal (sealing) or another sealing of the end face sealings described above or may be pinned or slipped onto the winding as a separate element. When the element is designed in a folded (pleated) manner, the end face may also be sealed by a side tape, a foil or a curing adhesive layer. In order to ensure that no particles are swept out of the chemical filter by the medium to be filtered, a particle separator element may optionally be integrated as a safety element (also known as secondary element or “police filter”) in the discharge direction, for example, in the core of the winding for a flow direction through the filter element from the outside to the inside, which is directly attached in front of the outlet of the medium to be filtered or, for example, represents the innermost layer of the winding. In this instance, the particle separator may be introduced as a separate element or as an integrated variation, and, in the integrated variation, a special material or, optionally, the carrier body may be used as particle layer. In the variation of the particle separator element being directly attached in front of the outlet of the medium to be filtered, the particulate filter may be connected, for example, to a one-piece connector element, for example, by way of welding, or by a multi-piece connector element, for example, by adhesion, clamping or pressing (for example, an open-pored foam). In particular, the particulate filter may be made up of an open-pored foam which is elastic and, owing to this characteristic, self-sealing.
[0036] According to an advantageous further refinement, the filter element may be designed substantially housingless in such a manner that the filter element includes a through-flowable outside. In this instance, the flow direction may be specified as needed from the inside to the outside or from the outside to the inside. Designing the filter element without a housing makes its manufacturing particularly cost effective and the filter element respectively lightweight and compact.
[0037] Despite the housingless architecture, the realization of an advantageous connection geometry to the filter element may be carried out with little effort via a socket element which protrudes more or less from an end face into the winding of the filter body and is connected to the end face sealing of the winding in an airtight manner. Depending on the depth of penetration of the socket element into the winding, it may be appropriate, regarding the stability of the filter element, to mold a support surface to the socket element upon which the end face of the winding rests. Depending on the design of the socket element, a protrusion into the winding may be completely omitted if a sufficiently tight connection of the end face sealing with the socket element may be achieved. Optionally, a respective socket element may also be attached at both end faces, and then the second socket element does not necessarily have to have the same measurements as the first socket element. For further contacting, the socket element may be provided with a suitable connector structure, for example, a pine tree profile or a comparable plug-in geometry, a bayonet closure, a screw thread having an axial or radial seal, and the like. In this instance, using a typical quick connector is also possible, and the socket element then either constitutes or includes the quick connector, or even constitutes the connector piece of the fluid line to be inserted (tubular part, hose section) which is plugged into such a coupling. Likewise, a further filter element may, for example, be connected to the socket element to enlarge the filter area.
[0038] The socket element may also have further outlet connections. Furthermore, the socket element may also be provided with a geometry (for example, a hexagon socket) which enables that a secure coupling or connection with the media line, into which the cleaned medium is to inserted, can be provided via commercially available tools. For this purpose, the socket element may be manufactured from plastic or metal.
[0039] As a further option, the socket element may also be mounted to the filter element in such a manner that said socket element is directly cast onto the filter body by a casting compound. In this instance, the sealing and attachment to the end face is carried out by the casting compound, which after curing may be comparably firm such as a conventional thermoplastic, for example, polypropylene or polyamide.
[0040] According to a further aspect of the present invention, an arrangement of filter elements is proposed, and at least two filter elements are fluidly connected in series. This ensures a segmentation of a filter section in the manner of a modular system. In doing so, the medium to be filtered flows respectively through the wall surface of a filter element, for example, from the outside to the inside. The filter elements may be rigidly or flexibly connected to one another so that an available space for installation may be used advantageously.
[0041] Advantageously, one or a plurality of filter elements may be fluidly connected or disconnected as needed. In doing so, the filter area may respectively be enlarged or reduced. In this way, particularly short-term load peaks may be taken into account when providing a system with the filtered medium.
[0042] According to a further aspect, the use of a filter element according to the present invention as an air filter and further, in particular, as a cabin air filter of a motor vehicle is proposed. The simple design and the lightweight and compact architecture may safe valuable installation space in the vehicle. The adsorbent of the filter medium, for example, activated carbon, and the possibility to combine adsorbents and/or absorbents and chemically active components with the filter medium enables not only the use in a passenger motor vehicle but also the use as a filter element in commercial vehicles, in which exposure to harmful substances has to be expected, for example, in agricultural vehicles which distribute pesticides and the like. The filter element may be easily exchanged as needed.
[0043] According to a further aspect, the use of a filter element according to the present invention as an air filter in a fuel cell system is proposed. The filter element may be easily exchanged as needed.
[0044] According to a further aspect, a filter system having a filter element according to the present invention is proposed, and the filter element has a filter body having a closed outer face surrounding a closed inner face, and the inner face encloses a central flow chamber, and at least one filter medium is situated between the outer face and the inner face, and the filter body includes, at least in sections, a wound layer having at least one adsorbent. Advantageously, such a filter system may be provided for an interior of a motor vehicle to filter inhaled air or also for a fuel cell system to filter the air supplied from the cathode side.
[0045] According to an advantageous further refinement, the filter element may be designed substantially housingless in such a manner that the filter element includes a through-flowable outside.
[0046] According to an advantageous embodiment, the adsorption filter area may be formed from a semi-finished product made up of at least one carrier plate and at least one fixed adsorbent layer having at least one adsorbent. A fixing or immobilizing of the adsorbent in the adsorbent layer prevents that the particles are swept out from the adsorption filter area.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] Further advantages result from the following description of the drawings. The drawings represent exemplary embodiments of the present invention. The drawings, the description and the claims include a plurality of combined features. The skilled person appropriately views the features also individually and further combines them in a purposeful manner.
[0048] FIG. 1 shows a cross sectional view of a filter element according to one exemplary embodiment of the present invention in the form of a candle filter having a wound layer having activated carbon as an adsorbent;
[0049] FIG. 2 shows a frontal view onto the bottom of the filter element as shown in FIG. 1 ;
[0050] FIG. 3 shows a frontal view onto the bottom of the filter element as shown in FIG. 1 having sealing beads at the longitudinal seams as a sealing of edges of the wound activated carbon layer;
[0051] FIG. 4 shows schematically a carrier body having a layer of activated carbon particles before winding;
[0052] FIG. 5 shows a cross sectional view of a filter element according to one exemplary embodiment of the present invention in the form of a candle filter having a wound activated carbon layer having a particulate filter in a socket element;
[0053] FIG. 6 shows a cross sectional view of a filter element according to one exemplary embodiment of the present invention in the form of a candle filter having a wound activated carbon layer having a particulate filter at an inner side of the filter element;
[0054] FIG. 7 shows a cross sectional view of a filter element according to one exemplary embodiment of the present invention in the form of a candle filter having a wound activated carbon layer having a particulate filter at an outer side of the filter element;
[0055] FIG. 8 shows schematically a row of coupled filter elements;
[0056] FIG. 9 shows schematically a motor vehicle having a filter system as a cabin filter;
[0057] FIG. 10 shows schematically a fuel cell system having a filter system in an air supply to a fuel cell stack;
[0058] FIG. 11 shows the structure of a semi-finished product having a carrier layer and a fixed adsorbent layer;
[0059] FIG. 11 a shows a layer of a fixed bed of activated carbon on a carrier layer;
[0060] FIG. 11 b shows a first embodiment of a semi-finished product of an adsorption filter layer formed from two layers according to FIG. 11 ;
[0061] FIG. 11 c shows a second embodiment of a semi-finished product formed from two layers according to FIG. 11 ;
[0062] FIG. 11 d shows a semi-finished product of an adsorption filter layer formed from one layer according to FIG. 11 and a cover layer; and
[0063] FIG. 11 e shows an adsorption filter layer from two layers of a semi-finished product according to FIG. 14 .
DETAILED DESCRIPTION OF THE INVENTION
[0064] In the figures, same or similar components are referenced having the same reference characters. The figures only show examples and are not to be understood as limiting.
[0065] In the following exemplary embodiments, activated carbon is used as an adsorbent in an exemplary manner. The use of other adsorbents is, however, also conceivable (for example, zeolites, silica gels, metal oxides such as aluminum oxide, copper oxide or manganese oxide, molecular sieves such as MOFs, phyllosilicates, and nanoclays), or mixtures of adsorbents.
[0066] In order to describe the present invention, FIG. 1 shows a cross sectional view of a filter element 10 according to one exemplary embodiment of the present invention in the form of a candle filter having wound activated carbon layer 14 . FIG. 2 shows a frontal view onto an end face, here onto bottom 44 of filter element 10 .
[0067] Filter element 10 includes a filter body 12 having a closed outer face 50 surrounding a closed inner face 52 . Filter body 12 is situated between outer face 50 and inner face 52 . Filter element 10 does not require a separate housing, that is, is substantially housingless so that medium 60 to be filtered, particularly air, may flow through outer face 50 . The flow direction is here from outer face 50 to inner face 52 ; however, the flow may, in a different embodiment, also be directed from inner face 52 to outer face 50 . In the shown example, ambient air 62 flows at outer face 50 into filter body 12 and discharges at inner face 52 as cleaned air 64 and leaves filter element 10 through socket element 42 as pure air 66 .
[0068] At an end face 30 , the filter element is provided at one end face with socket element 42 and, at the opposite lying end face 32 , with a bottom plate 48 sealing the interior area of filter element 10 at bottom 44 . Socket element 42 is directly attached onto filter body 12 .
[0069] The end face edges of filter body 12 are provided with a sealing 38 at bottom 44 of filter element 10 . Further, as it is shown in FIG. 1 , the edges of filter body 12 are, at the opposite lying end face 30 , sealed by an end plate 46 around socket element 42 . End plate 46 may also constitute a sealing 40 . Particularly during the winding process, sealings 38 , 40 may be formed using, for example, hot glue or the like. For example, socket element 42 may be imbedded into sealing 40 .
[0070] As the frontal view in FIG. 3 shows, axial edges 24 , 26 of filter body 12 are sealed by a sealing 34 at outer face 50 and a sealing 36 at inner face 52 . Sealings 34 , 36 may be designed, for example, as sealing beads. Sealings 34 , 36 may likewise be formed during the winding process. Thus, a flow of the medium 60 to be filtered through the filter element may necessarily occur only through filter body 12 .
[0071] In this example, filter element 10 has a circular cross section, and filter body 12 is formed from wound layers 14 which include activated carbon. The immobilized activated carbon (adsorbent) forms the actual filter medium 16 .
[0072] For this purpose, filter body 12 is formed as a winding having wound layers 14 , and a layer 22 having activated carbon is applied onto carrier body 20 , for example, a flat layer of fiber nonwoven fabric, and, carrier body 20 is substantially shaped as a circular cross section by winding up carrier body 20 , which is indicated by a curved arrow. This is sketched in FIG. 4 . In this instance, the inner diameter of filter body 12 may be specified by the diameter of a mandrel around which carrier body 20 is wound. The activated carbon is immobilized on carrier body 20 and, for this purpose, may, for example, be imbedded into an adhesive. Alternatively or additionally, layer 22 may be covered also with a further nonwoven fabric layer (not shown). In addition to activated carbon, further components may be added which specifically remove specific parts of the medium 60 to be filtered. Optionally, two coated carrier bodies 20 may be positioned on top of each other with their coated side (not shown) and be wound up.
[0073] FIGS. 5 through 7 show the sectional views of a filter element 10 according to the exemplary embodiment of the present invention according to FIG. 1 in the form of a candle filter having a wound activated carbon layer in which respectively one particulate filter 70 or, additionally or alternatively, one aerosol filter 80 is shown in different locations. Advantageously, filter element 10 is situated in a filter system 100 according to the present invention, in which medium 60 to be filtered, particularly ambient air, is supplied and filtered medium 60 is discharged, particularly pure air. Filter element 10 may be easily exchanged and may be coupled to a line system (not shown) in a simple manner by way of its socket element 42 , for example, by way of a quick connector.
[0074] In FIG. 5 , a particulate filter 72 is situated in socket element 42 . In FIG. 6 , a particulate filter 74 is situated at inner face 52 of filter body 12 . In FIG. 7 , a particulate filter 76 is situated at outer face 50 of filter body 12 . Embodiments in which such additional filters are simultaneously provided at a plurality of locations are, of course, also conceivable.
[0075] A further possibility for application is provided in that filter body 12 is inserted into a tube having a porous or a lattice-like shape and is fixedly installed directly into the intake system, for example, in an air intake system of stationary combustion system. In this instance, filter body 12 may be several meters long, which takes in air via the inner cross section. Through a porous or lattice-like center tube implemented in a rigid or flexible configuration (depending on the installation situation and length), the inner cross section may be kept stable and open for longer lengths. Such an embodiment may reduce the flow speed in the medium to be filtered and increase the capacity of the filter.
[0076] Advantageously, an exchangeable particulate filter 70 or coarse dust filter is coupled to filter element 10 .
[0077] In addition to a physical mixture of two or a plurality of adsorbents, the use of two adsorbent layers separated at a boundary surface is also conceivable within one wound layer. For this purpose, mixtures out of two or a plurality of adsorbents again may be used.
[0078] In order to further improve the adsorption performance, specific materials in the form of fibers or foam may be used as carrier bodies and/or particulate filter layers. Examples are as follows: active carbon nonwoven fabric or activated carbon mats and nonwovens or foams which are impregnated with adsorbents (for example, activated carbon, zeolites, silica gels, metal oxides such as aluminum oxide, copper oxide or manganese oxide, molecular sieves such as MOFs, phyllosilicates, and nanoclays).
[0079] The simple design and the simple construction of filter element 10 achieves an increased service life and a reduced flow speed so that the filtering effect is particularly high. Free space (for example, in a chimney) may be used.
[0080] Depending on the change interval, the user may either change activated carbon filter element 10 or the particulate filter and does not have to change complete filter system 100 . In addition, various filter element types (for example, filter elements having fine fibers or microfibers) may be adapted to the active carbon filter element depending on the requirement profile of the user.
[0081] The particle filtration may be taken over by a pleated filter element (not shown). Alternatively or additionally, a non-pleated coarse dust mat may be simply put over the activated carbon filter element as a round element or may be attached at the activated carbon filter element by a Velcro fastener or other gripping elements. For example, a nonwoven fabric or a semi-finished product made out of open-pored foam may be used as a coarse dust mat.
[0082] With regard to the different requirements related to volume flows and service life, the wound filter element 10 may be regarded as a modular kit which enables to react via the cylinder height and the diameter to the different requirements by using the same connector components as a result of which tool expenses may be advantageously reduced.
[0083] An extension of the service life of filter element 10 may be achieved under conditions of air containing large amounts of particulate matter and few chemical pollutants. Immobilized adsorbent systems or adsorbent layers demonstrate advantages regarding mechanical stability and homogeneity.
[0084] Significantly higher residence times may result in a higher efficiency and, for this reason, in a lower breakthrough in filter element 10 , and a higher filter capacity. Adapting the adsorption performance to the respective requirement profile and to the installation space by an appropriate selection of materials may be easily realized, for example, by varying the used material amount, that is, the used surface weight.
[0085] A combination of a plurality of adsorbents is possible through defined wound layers, and a placement on the inflow side or the outflow side enables an adaptation to a sorption kinetics of specific target gases. Since activated carbon has a certain selectivity during adsorption, not all relevant harmful gases are equally well received, in particular, complex gas mixtures as they occur in reality. Moreover, other substances for which the activated carbon has a greater affinity may supplant already adsorbed molecules. These effects may be compensated by using specialized adsorbents. Relevant material groups for this purpose are zeolites, silica gels, aluminum oxide and other porous metal oxides (for example, copper oxide and manganese oxide) and molecular sieves (for example, MOFs, phyllosilicates and nanoclays). The individual adaptation of the adsorption performance to the requirements for specific gases are further advantages when using different adsorbents. When using adsorbents which chemically bind harmful gases, a later desorption of the harmful gases may be prevented. A specific spatial arrangement of the materials in the wound layers enables to exploit further advantageous effects. For example, the first wound layer of filter element 10 may function as a protective layer in that a specialized material having a high affinity and capacity for a gas A is used. Hence, the underlying wound layers (for example, activated carbon having a good broad effect) are protected from gas A improving the adsorption efficiency for a gas B (similar to gas A) because pores are not blocked by gas A and, for this reason, two molecule types are not competing for equally large pores in the activated carbon.
[0086] A respective mixture theoretically enables that any number of materials is accommodated in one single wound layer. In this way, the adsorption performance may be adapted to the requirements when the installation space is optimally used.
[0087] Pleated particulate filters optionally possible increase, as pre-filters, the service life of filter element 10 or, as a downstream connected safety element (“police filter”), minimize the contamination of the system to be protected (for example, the discharge of adsorption particles such as activated carbon dust).
[0088] FIG. 8 shows an advantageous arrangement 90 in the form of a series connection of a plurality of filter elements 10 , the example here showing three filter elements 10 a , 10 b , and 10 c . Such an arrangement is particularly advantageous for filter system 100 , which has long filter sections and/or high media flow.
[0089] Such a series connection of short filter elements 10 enables the use of the installation space more effectively; a plurality n, however, at least two individual filter elements 10 , are connected by connecting pieces 92 , and connecting pieces 92 are advantageously flexibly designed, for example, as a bellow. In doing so, the complete filter arrangement 90 adapts to the installation space.
[0090] The flexible connection piece 92 may also be a fixed component of socket element 32 ( FIGS. 1, 5, 6, 7 ) or represent said component. The flexibility may be achieved by the used material for connection piece 92 itself or by a defined geometric form, for example, a bellow. Dividing the entire air stream into n-segments or filter elements 10 results in the possibility to reduce the line cross section with increasing distance from the outlet of arrangement 90 .
[0091] The acoustic of the air intake section may be positively influenced by acoustic measures integrated into connection pieces 92 which are known per se, for example, lambda quarter-wave tubes, resonators or other noise-reducing measures. Moreover, sensors (not shown) may be provided at least in part in and/or between filter elements 10 , for example, temperature sensors, flow speed sensors, gas sensors, humidity sensors, pressure sensors, etc.
[0092] Depending on the load conditions and the thereto related need for a filtered medium, for example, air, it is also possible to integrate control elements which ensure that a part of the filter section is disconnected. This deactivation may be carried out by an electronic control element 94 or an element which is controlled by pressure or reacts to pressure changes (for example, a vacuum box, a prestressed flap or the like).
[0093] In the shown example of three filter elements 10 a , 10 b , 10 c forming the filter section, filter element 10 c , which has the greatest distance from outlet 43 of the filter section, may be configured having less storage capacity (chemical and/or physical) because this filter element 10 c is only required at load peak and peak load is not the rule regarding operating requirements.
[0094] If the pressure loss of first two filter elements 10 a , 10 b is too high, third filter element 10 c may be connected to carry out the filter element change. Connecting or disconnecting is also advantageous in the case of a temporary, heavy harmful gas burden because the disconnected filter area of filter element 10 c may be connected in this instance and, thus, reduce the flow speed in the individual filter elements 10 a , 10 b , 10 c under the same load. In doing so, the residence time and, thus, the contact probability of the harmful gases is increased in the filter element leading to an increased separation of the harmful gases.
[0095] Of course, more than one filter element 10 may be connected as needed, particularly then when more than three filter elements 10 are connected in series. Appropriately, filter elements 10 at the end of the series connection, which are at a distance from the outlet of the series connection, may be connected and/or disconnected.
[0096] Particularly advantageous is the use of a filter system 100 or filter element 10 according to the present invention as an air filter, in particular, as a cabin air filter of a motor vehicle 300 as indicated in a simplified manner in FIG. 9 . Ambient air is taken in, guided through filter system 100 , in doing so, cleaned by filter element 10 and emitted in the interior of vehicle 300 . In this instance, filter element 10 may be easily exchanged. If applicable, the filter element may be coupled to one or a plurality of separate particle filters and/or aerosol filters which, for example, may be exchanged separately if needed.
[0097] FIG. 10 shows schematically a fuel cell system 200 having a filter system 100 in an air supply 212 , 214 to a fuel cell stack 220 . Fuel cell system 200 is only outlined schematically; typical components known to the skilled person are not embodied. Fuel cell system 200 is shown having a housing 210 into which the air enters via air supply 212 and is supplied as cathode air via filter system 100 and thereto connected air supply 214 to fuel cell stack 220 .
[0098] A separate housing is not necessary for filter element 10 . In this instance, filter element 10 serves as a cathode air filter and may, for example, have a coarse dust mat for filtering particles instead of a folded (pleated) particulate filter or in addition to a particulate filter. The coarse dust mat may be designed as a foam or a nonwoven fabric mat.
[0099] The particulate filter element may be connected upstream of filter element 10 and functions as a pre-filter. The particulate filter element may also be connected downstream of filter element 10 and then functions as a so-called “police filter.” If the particulate filter element is only partially suitable for filtering aerosols, it is also possible to attach, preferably behind the particulate filter element, a second filter element specifically suitable for the filtration of aerosols. A combination of pre-filter, filter element 10 and downstream safety element (“police filter”) is conceivable.
[0100] The upstream particulate filter keeps away dust particles and aerosols from filter element 10 so that a premature increased pressure loss in filter element 10 , caused by imbedded dust particles, is prevented. In doing so, the service life (life span) of filter element 10 is increased. The downstream particulate filter may, in addition to the dust particles and aerosols captured from the air flow, also retain activated carbon particles possibly discharging from the wound layers of filter element 10 . In doing so, for example, an additional protective function for the fuel cell system is realized and any damage by particulate pollutants is prevented.
[0101] Fuel cell vehicles need an air filter on the cathode side of fuel cell stack 220 , which also separates harmful gases. This is realized by a physical and chemical filter. Advantageous in this instant are activated carbon filters, filter body 10 of which is designed as a circular element having a wound layer, as it has been described previously. Owing to the large mass flow in high-capacity fuel cells (for example, 80 kW), such circular elements require very long filter bodies, which may become problematic regarding the installation space, to offer the required filtration surface and contact time, particularly in regard to filter element 10 which includes the adsorbent.
[0102] For this reason, particularly advantageous is a geometric sequencing of a plurality of filter elements 10 , as described in the arrangement in FIG. 9 . The geometric sequencing corresponds in terms of flow with a parallel connection of filter elements 10 . Particularly advantageous for illustrating a sufficient dynamic for the cathode air supply of the fuel cell stack 220 is the possibility of activating or deactivating as needed one or a plurality of filter elements 10 at the end of the series of filter elements 10 at a distance from fuel cell stack 220 or the clean air outlet from the series of filter elements 10 . If filter element 10 were illustrated as an individual filter body having wound layers for completely flowing through, for example, an 80 kW fuel cell system, it would, as a function of the service life, be very high regarding the installation space which, in turn, typically complicates the installation space situation. Furthermore, a filter system may be designed in this manner from individual filter elements 10 as a modular system, which is cost effective.
[0103] FIG. 11 illustrates a basic structure of a semi-finished product having a layer 300 having a fixed bed of adsorbent particles including a carrier plate 302 , a cover layer 303 , an adsorbent layer 304 , for example, in form of a fill layer, having immobilized adsorbent particles. Such a semi-finished product may be used to manufacture a winding body of a filter element.
[0104] Further possible constructions of an adsorption filter layer for a filter element according to the present invention may be concluded from FIGS. 11 a -11 e . FIG. 11 a shows a layer 300 of a fixed bed of activated carbon particles, including a carrier layer 301 and a fill layer 302 having activated carbon particles.
[0105] Two of these layers may be connected in different ways with semi-finished products which may form an adsorption filter layer as a single layer or as multiple layers. In the embodiment according to FIG. 11 b , two such layers 300 are superimposed in such a manner that fill layers 302 are lying on top of each other, and a semi-finished product is formed which on both sides is bordered by carrier elements 301 . A plurality of semi-finished products may be stacked on top of each other to form a comprehensive adsorption filter layer.
[0106] In the embodiments according to FIG. 11 c , two such layers 300 are superimposed in the same orientation; however, a greater number of such layers 300 may also be superimposed in such a manner. In order to form a finished adsorption filter layer, a cover layer 303 may be applied onto fill layer 302 .
[0107] FIG. 11 d shows an embodiment of a semi-fished product having a layer 302 of a fixed bed of activated carbon particles applied on a carrier layer 301 and covered by a cover layer 303 . Semi-finished product 310 may form a comprehensive adsorption filter layer either as a single layer arrangement or, as shown in FIG. 11 e , as a two or multiple-layer arrangement of superimposed semi-finished products 310 .
[0108] In the embodiments, fill layers 302 are connect to the respective carrier and cover layers by way of fine nets of adhesive threads; however, other connection types may also be chosen.
[0109] The activation or deactivation is also advantageous in the case of high harmful gas burden, for example, in tunnels having a high degree of air impurities, because the deactivated filter area may the activated in this instance and, thus, reduce the flow speed in the individual filter elements 10 under the same load. In doing so, the residence time and, thus, the contact probability of the harmful gases increases in filter element 10 leading to an increased separation of the harmful gases.
[0110] In contrast to conventional filter elements used thus far, for example, pleated filter elements, filter elements 10 having wound layers according to the present invention offer relatively slow flow speeds and enable an advantageous, increased contact time of the medium to be filtered with the filter medium ensuring a reliable adsorption or absorption of the pollutants in filter element 10 . In doing so, the functionality of filter element 10 or the filtration efficiency and also the adsorption efficiency is improved. | 4y
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application of application Ser. No. 09/917,763, filed Jul. 31, 2001, now U.S. Pat. No. 6,912,533, which is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to allocating data mining processing tasks using data mining agents that provide efficient hardware utilization of the data mining system.
BACKGROUND OF THE INVENTION
Data mining is a technique by which hidden patterns may be found in a group of data. True data mining doesn't just change the presentation of data, but actually discovers previously unknown relationships among the data. Data mining is typically implemented as software in or in association with database systems. Data mining includes several major steps. First, data mining models are generated based on one or more data analysis algorithms. Initially, the models are “untrained”, but are “trained” by processing training data and generating information that defines the model. The generated information is then deployed for use in data mining, for example, by providing predictions of future behavior based on specific past behavior.
Data mining typically involves the processing of large amounts of data, which consumes significant hardware resources. As a result, it is desirable to configure the data mining software system for efficient utilization of the hardware resources. This may present a problem. For example, if a data mining software system is configured to use all of the processors of a given hardware system, the data mining software system must either perform complex internal allocation of tasks to multiple threads/processes, or the data mining software system must allow the operating system to perform the allocation. If internal allocation is used, significant complexity is added to the data mining software system. This can cause difficulties in generating, debugging, and maintaining the data mining software system. If the operating system is used to perform allocation, the operating system will typically use a general-purpose allocation scheme. This general purpose allocation scheme cannot produce optimal usage of resources since data mining demands and behavior are significantly different than those that the typical general purpose allocation scheme has been designed to handle.
An additional problem may arise if, once a data mining processing task has started execution, the hardware system servicing the task becomes overloaded due to other tasks being executed. This may cause degradation in the performance of the data mining processing task, or, in some cases, cause the data mining processing task to become unexecutable. For example, if a data mining processing task requires a certain minimum number of processors to execute and the number of available processors is always fewer than that minimum, due to other tasks, the data mining processing task will never execute. This is unacceptable from a performance standpoint, since the typical data mining system expects a data mining processing task to run to completion in its current environment, without interruption.
A need arises for a technique by which data mining processing tasks may be allocated without complex internal schemes, yet resulting in better performance than is possible with general-purpose operating system based schemes.
SUMMARY OF THE INVENTION
The present invention is a method, system, and computer program product for allocating data mining processing tasks that does not use complex internal schemes, yet results in better performance than is possible with general-purpose operating system based schemes. The present invention uses a data mining agent that operates autonomously, proactively, reactively, deliberatively and cooperatively to allocate and reallocate data mining processing tasks among computer systems, and/or among processors.
In one embodiment, the present invention is a method of data mining performed in a data mining agent executing in a computer system, the method comprising the steps of examining a request queue comprising at least one request for data mining processing, determining if the at least one request for data mining processing can be processed, accepting the at least one request for data mining processing if it is determined that the at least one request for data mining processing can be processed, and processing the accepted request for data mining processing in the computer system.
In one aspect of this embodiment of the present invention, the determining step comprises the steps of determining if an algorithm required to process the at least one request for data mining processing is supported by the computer system, if the algorithm required to process the at least one request for data mining processing is supported, determining whether the computer system is available for additional processing, if the computer system is not available for additional processing, determining whether the computer system will become available for additional processing before other computer systems that might process the at least one request, if the computer system is available for additional processing, or if the computer system will become available for additional processing before other computer systems that might process the at least one request, determining whether the computer system will be able to complete requested processing in an allotted time, and if the computer system will be able to complete the requested processing in the allotted time, determining that the computer system can process the at least one request for data mining processing. The at least one request for data mining processing comprises data defining at least one algorithm that must be performed in order to perform the requested data mining processing. There is data defining algorithms that are supported by the computer system. The step of determining if an algorithm required to process the at least one request for data mining processing is supported comprises comparing the data defining at least one algorithm that must be performed in order to perform the requested data mining processing with data defining algorithms that are supported by the computer system. The data defining at least one algorithm that must be performed in order to perform the requested data mining processing and the data defining algorithms that are supported by the computer system are in extensible markup language format.
In one aspect of this embodiment of the present invention, the step of determining whether the computer system is available for additional processing comprises the step of determining whether available idle time of the computer system is greater than a predefined or a dynamically calculated threshold.
In one aspect of this embodiment of the present invention, the computer system comprises a plurality of processors and the step of determining whether the computer system is available for additional processing comprises the step of determining whether any of the plurality of processors is available for additional processing. The step of determining whether any of the plurality of processors is available for additional processing comprises the step of determining, for each of the plurality of processors, whether available idle time of the processor is greater than a predefined or a dynamically calculated threshold.
In one aspect of this embodiment of the present invention, the step of determining whether the computer system is available for additional processing comprises the step of determining availability of the computer system for additional processing relative to at least one other computer system.
In one aspect of the present invention, the step of determining whether the computer system will become available for additional processing before other computer systems that might process the at least one request comprises the steps of estimating a time to availability of the computer system, exchanging an estimate of a time to availability of the at least one other computer system, and comparing the time to availability of the computer system with the time to availability of the at least one other computer system. The step of determining whether the computer system will be able to complete requested processing in an allotted time comprises the steps of estimating a time to completion for the requested processing on the computer system, comparing the time to completion for the requested processing on the computer system with time allocation information included in the request for data mining processing.
In one embodiment, the present invention is a method of data mining performed in a data mining agent executing in a computer system, the method comprising the steps of determining that the computer system is overloaded, querying at least one other computer system to determine whether the at least one other computer system can complete a data mining processing task being performed on the computer system faster than the computer system, determining whether the at least one other computer system can complete the data mining processing task being performed on the computer system faster than the computer system, and if the at least one other computer system can complete the data mining processing task faster than the computer system, migrating the processing from the computer system to the at least one other computer system.
In one aspect of this embodiment of the present invention, the migrating step comprises the steps of reserving the at least one other computer system for migration, interrupting and checkpointing the data mining processing task on the computer system, and enqueueing a request to the at least one other computer system for continued processing of the data mining processing task.
In one aspect of this embodiment of the present invention, the step of determining that the computer system is overloaded comprises the step of determining that the computer system is overloaded if a utilization of a processor of the computer system is greater than a predefined threshold for a predefined time.
In one aspect of this embodiment of the present invention, the querying step comprises the step of generating an estimate of a time to complete the data mining processing task. The generating step comprises the steps of estimating an amount of processing that must be performed to complete the data mining processing task, estimating a processor utilization that will be available to process the data mining processing task, and estimating a time to complete the data mining processing task based on the estimate of the amount of processing that must be performed, the estimate of available processor utilization, and a speed of the processor. The querying step further comprises the step of requesting information from the at least one other computer system, the information including a speed of the at least one other computer system and an estimate of processor utilization of the at least one other computer system.
In one aspect of this embodiment of the present invention, the step of determining whether the at least one other computer system can complete a data mining processing task being performed on the computer system faster than the computer system comprises the step of estimating a time to complete the data mining processing task for the at least one other computer system based on the estimate of the amount of processing that must be performed to complete the data mining processing task, the speed of the at least one other computer system and the estimate of processor utilization of the at least one other computer system. The step of determining whether the at least one other computer system can complete a data mining processing task being performed on the computer system faster than the computer system further comprises the steps of adding an estimate of a time to migrate the data mining processing task to the at least one other computer system and the estimate of the time to complete the data mining processing task for the at least one other computer system, comparing the estimate of the time to complete the data mining processing task for the computer system with the estimate of the time to complete the data mining processing task for the at least one other computer system, and determining whether the at least one other computer system can complete the data mining processing task being performed on the computer system faster than the computer system.
In one aspect of this embodiment of the present invention, the querying step further comprises the step of transmitting to the at least one other computer system the estimate of the amount of processing that must be performed to complete the data mining processing task, and receiving from the at least one other computer system an estimate of a time to complete the data mining processing task for the at least one other computer system
In one aspect of this embodiment of the present invention, the step of determining whether the at least one other computer system can complete a data mining processing task being performed on the computer system faster than the computer system further comprises the steps of adding an estimate of a time to migrate the data mining processing task to the at least one other computer system and the estimate of the time to complete the data mining processing task for the at least one other computer system, comparing the estimate of the time to complete the data mining processing task for the computer system with the estimate of the time to complete the data mining processing task for the at least one other computer system, and determining whether the at least one other computer system can complete the data mining processing task being performed on the computer system faster than the computer system.
In one embodiment, the present invention is a method of data mining performed in a data mining agent executing in a computer system, the method comprising the steps of determining that a processing load in the computer system is high relative to at least one other computer system, determining a remaining cost of completing processing of a data mining processing task being processed by the computer system, determining whether the at least one other computer system can complete processing of the data mining processing task at a lower cost than the computer system, and if the at least one other computer system can complete processing of the data mining processing task at a lower cost than the computer system, migrating processing of the data mining processing task to the at least one computer system.
In one aspect of this embodiment of the present invention, the step of determining that a processing load in the computer system is high relative to at least one other computer system comprises the steps of determining a processor utilization of the computer system, determining a processor utilization of the at least one other computer system, and determining that the processor utilization of the computer system is greater than a predefined amount higher than the processor utilization of the at least one other computer system.
In one aspect of this embodiment of the present invention, the remaining cost of completing processing of a data mining processing task may be determined based on a time to complete processing of the data mining processing task. The remaining cost of completing processing of a data mining processing task may be determined based on a time to complete processing of the data mining processing task and on additional factors, including actual costs of use of the computer system. The step of determining a remaining cost of completing processing of a data mining processing task being processed by the computer system may comprise the steps of estimating an amount of processing that must be performed to complete the data mining processing task, estimating a processor utilization that will be available to process the data mining processing task, and estimating a time to complete the data mining processing task based on the estimate of the amount of processing that must be performed, the estimate of available processor utilization, and a speed of the processor. The method may further comprise the step of estimating additional factors, including actual costs of use of the computer system.
In one aspect of this embodiment of the present invention, the step of determining whether the at least one other computer system can complete processing of the data mining processing task at a lower cost than the computer system comprises the step of soliciting a bid for completing processing of the data mining processing task from the at least one other computer system.
In one aspect of this embodiment of the present invention, the soliciting step comprises the steps of transmitting a request for a bid to the at least one other computer system, the request for the bid including information relating to the amount of processing that must be performed to complete the data mining processing task, and receiving a bid from the at least one other computer system, the bid including an estimate of a cost of completing processing of the data mining processing task on the at least one other computer system.
BRIEF DESCRIPTION OF THE DRAWINGS
The details of the present invention, both as to its structure and operation, can best be understood by referring to the accompanying drawings, in which like reference numbers and designations refer to like elements.
FIG. 1 is an exemplary block diagram of a data mining system, in which the present invention may be implemented.
FIG. 2 is an exemplary block diagram of a database/data mining system shown in FIG. 1 .
FIG. 3 is an exemplary data flow diagram of a data mining process, which may be implemented in the system shown in FIG. 1 .
FIG. 4 a is an exemplary block diagram of one embodiment of a data mining system shown in FIG. 1 .
FIG. 4 b is an exemplary block diagram of one embodiment of a data mining system shown in FIG. 1 .
FIG. 5 is an exemplary data flow diagram of processing performed by a data mining agent, according to the present invention.
FIG. 6 is an exemplary data flow diagram of data mining agents shown in FIG. 5 selecting tasks to process.
FIG. 7 is an exemplary flow diagram of a data mining processing task request selection process, according to the present invention.
FIG. 8 is an exemplary flow diagram of a process performed by a step of the data mining processing task request selection process shown in FIG. 7 .
FIG. 9 is an exemplary flow diagram of one embodiment of a data mining processing task migration process, according to the present invention.
FIG. 10 is an exemplary flow diagram of one embodiment of a data mining processing task migration process, according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
An exemplary data mining system 100 , in which the present invention may be implemented, is shown in FIG. 1 . System 100 includes a data mining system 102 that is connected to a variety of sources of data. For example, system 102 may be connected to a plurality of internal or proprietary data sources, such as systems 104 A- 104 N. Systems 104 A- 104 N may be any type of data source, warehouse, or repository, including those that are not publicly accessible. Examples of such systems include inventory control systems, accounting systems, scheduling systems, etc. System 102 may also be connected to a plurality of proprietary data sources that are accessible in some way over the Internet 108 . Such systems include systems 106 A- 106 N, shown in FIG. 1 . Systems 106 A- 106 N may be publicly accessible over the Internet 108 , they may be privately accessible using a secure connection technology, or they may be both publicly and privately accessible. System 102 may also be connected to other systems over the Internet 108 . For example, system 110 may be privately accessible to system 102 over the Internet 108 using a secure connection, while system 112 may be publicly accessible over the Internet 108 .
The common thread to the systems connected to system 102 is that the connected systems all are potential sources of data for system 102 . The data involved may be of any type, from any original source, and in any format. System 102 has the capability to utilize and all such data that is available to it.
An exemplary embodiment of data mining system 102 is shown in FIG. 2 . Data mining system 102 utilizes data, such as externally stored data 204 and internally stored data 206 , which is obtained from data sources such as the proprietary and public data sources shown in FIG. 1 . Data mining system 102 also includes data mining engine 208 . Externally stored data 204 is typically stored in a database management system and is accessed by data mining system 102 . The database management system typically includes software that receives and processes queries of the database, such as those received from data mining system 102 , obtains data satisfying the queries, and generates and transmits responses to the queries, such as to data mining system 102 . Internally stored data 206 contemplates an embodiment in which data mining engine 208 is combined with, or implemented on, a database management system. In either case, data 204 or 206 includes data, typically arranged as a plurality of data tables, such as relational data tables, as well as indexes and other structures that facilitate access to the data. Data mining engine 208 performs data mining processes, such as processing data to generate data mining models and responding to requests for data mining results from one or more users, such as user 212 .
An exemplary data flow diagram of a data mining process, which may be performed by data mining engine 208 , including building and scoring of models and generation of predictions/recommendations, is shown in FIG. 3 . The training/model building step 302 involves generating the models that are used to perform data mining recommendation/prediction, clustering, association rule generation, etc. The inputs to training/model building step 302 include training parameters 304 , training data 306 , and untrained models 308 . For some types of models, such as neural network or self-organizing map models, untrained models 308 may include initialized or untrained representations of the models in addition to algorithms that process the training data 306 in order to actually build the models. Such a representation includes a structural representation of the model that either does not actually contain data that makes up the model, or contains only default data or parameters. The actual data or parameters are generated and entered into the representation during training/model building step 302 by the model building algorithms. For other types of models, such as tree models or association rule models, untrained models 308 do not include untrained representations of the models, but only include the algorithms that process the training data 306 in order to actually build the models. Training parameters 304 are parameters that are input to the data-mining model building algorithms to control how the algorithms build the models. Training data 306 is data that is input to the algorithms and which is used to actually build the models. Model building can also partition “build data” into training, evaluation, and test datasets. The evaluation dataset can be used by the model building algorithm to avoid overtraining, while the test dataset can be used to provide error estimates of the model.
Training/model building step 302 invokes the data mining model building algorithms included in untrained models 308 , initializes the algorithms using the training parameters 304 , processes training data 306 using the algorithms to build the model, and generates trained model 310 . Trained model 310 may include rules that implement the conditions and decisions that make up the operational model, for those types of models that use rules. As part of the process of building trained model 310 , trained model 310 is evaluated and, for example, in the case of decision tree models, those rules that decrease or do not contribute to the quality, i.e. prediction accuracy, of the model are eliminated from the model. The remaining rules of trained model 310 are encoded in an appropriate format and are deployed for use in making predictions or recommendations. For those types of models that do not use rules, such as neural networks, the trained model 310 includes an appropriate representation of the model encoded in an appropriate format and deployed for use in making predictions or recommendations
Scoring step 312 involves using the deployed trained model 310 to make predictions or recommendations based on new data that is received. Trained model 310 , prediction parameters 314 , and prediction data 316 are input to scoring step 312 . Trained models 310 include one or more sets of deployed rules that were generated by model building step 302 . Prediction parameters 314 are parameters that are input to the scoring step 318 to control the scoring of trained model 310 against prediction data 316 and are input to the selection and prediction/recommendation step 320 to control the selection of the scored rules and the generation of predictions and recommendations
Prediction data 316 is processed according to deployed rules or other representation of the model included in trained model 310 , as controlled by prediction parameters 314 . In the case of a rule based model, scores are generated for prediction data 316 based upon each rule in the set of deployed rules included in trained model 310 . Typically, a trained model 310 can be defined in terms of a function of input variables producing a prediction/recommendation based on the input variables. The function is evaluated using the input prediction data 316 and scores are generated. The scores indicate how closely the function defined by the model matches the prediction data, how much confidence may be placed in the prediction, how likely the output prediction/recommendation from the model is to be true, and other statistical indicators. Scored data 318 is output from scoring step 312 and includes predictions or recommendations for each scored record in prediction data 316 , along with corresponding probabilities for each scored record. Scored data 318 is input to selection and prediction/recommendation generation step, which evaluates the probabilities associated with each record of scored data 318 and generates predictions/recommendations based on the scored data. Records may be selected based on prediction parameters 314 provided by the user, for example, to filter records that do not meet some probability threshold. The generated predictions/recommendations are output 322 from step 320 for use in any post data mining processing.
An exemplary block diagram of one embodiment of a database/data mining system 102 , shown in FIG. 1 , is shown in FIG. 4 a . Database/data mining system 102 is typically a programmed general-purpose computer system, such as a personal computer, workstation, server system, and minicomputer or mainframe computer. Database/data mining system 102 includes one or more processors (CPUs) 402 A- 402 N, input/output circuitry 404 , network adapter 406 , and memory 408 . CPUs 402 A- 402 N executes program instructions in order to carry out the functions of the present invention. Typically, CPUs 402 A- 402 N are one or more microprocessors, such as an INTEL PENTIUM® processor. FIG. 4 illustrates an embodiment in which data mining system 102 is implemented as a single multi-processor computer system, in which multiple processors 402 A- 402 N share system resources, such as memory 408 , input/output circuitry 404 , and network adapter 406 . However, the present invention also contemplates embodiments in which data mining system 102 is implemented as a plurality of networked computer systems, which may be single-processor computer systems, multi-processor computer systems, or a mix thereof.
Input/output circuitry 404 provides the capability to input data to, or output data from, database/data mining system 102 . For example, input/output circuitry may include input devices, such as keyboards, mice, touchpads, trackballs, scanners, etc., output devices, such as video adapters, monitors, printers, etc., and input/output devices, such as, modems, etc. Network adapter 406 interfaces database/data mining system 102 with network 410 . Network 410 may be any standard local area network (LAN) or wide area network (WAN), such as Ethernet, Token Ring, the Internet, or a private or proprietary LAN/WAN.
Memory 408 stores program instructions that are executed by, and data that are used and processed by, CPU 402 to perform the functions of the database/data mining system 102 . Memory 408 may include electronic memory devices, such as random-access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), electrically erasable programmable read-only memory (EEPROM), flash memory, etc., and electromechanical memory, such as magnetic disk drives, tape drives, optical disk drives, etc., which may use an integrated drive electronics (IDE) interface, or a variation or enhancement thereof, such as enhanced IDE (EIDE) or ultra direct memory access (UDMA), or a small computer system interface (SCSI) based interface, or a variation or enhancement thereof, such as fast-SCSI, wide-SCSI, fast and wide-SCSI, etc, or a fiber channel-arbitrated loop (FC-AL) interface.
Memory 408 includes data 206 , database management processing routines 412 , data mining processing routines 414 A- 414 Z, data mining agents 416 A- 416 Z, and operating system 418 . Data 206 includes data, typically arranged as a plurality of data tables, such as relational database tables, as well as indexes and other structures that facilitate access to the data. Database management processing routines 412 are software routines that provide database management functionality, such as database query processing.
Data mining processing routines 414 A- 414 Z are software routines that implement the data mining processing performed by the present invention. Data mining processing routines 414 A- 414 Z interact with and are used by data mining agents 418 A- 418 Z. Data mining agents 418 A- 418 Z are software components that perform data mining processing, but which have been enhanced to be capable of flexible, autonomous action in the environment. That is, each data mining agent can operate autonomously, proactively, reactively, deliberatively and cooperatively. Autonomous operation means that the data mining agent has control over its own behavior and internal states. Proactive operation means that the data mining agent can act in anticipation of future goals or tasks. Reactive operation means that the data mining agent can respond in a timely fashion to changes in its environment, including changes in available processing tasks, etc. Deliberative operation means that the data mining agent can reflect on or process received information before acting on that information. Cooperative operation means that the data mining agent can communicate with other data mining agents to coordinate their actions. Operating system 418 provides overall system functionality.
An exemplary block diagram of another embodiment of a data mining system 102 is shown in FIG. 4 b . This embodiment includes a plurality of computer systems, such as computer systems 420 A-X, which communicate with each other over network 410 . Each computer system 420 A- 420 X includes components similar to those shown in FIG. 4 a , but not all of these components are shown in FIG. 4 b . Some of the computer systems, such as computer systems 420 A and 420 X include one or more active, running data mining agents. For example, computer system 420 A includes active, running data mining agent 422 , while computer system 420 X includes a plurality of active, running data mining agents 424 A- 424 Z. Computer system 420 N includes machine agent 426 . Machine agent 426 is a software component that provides monitoring and coordination capabilities to computer system 420 N even in the absence of any active, running data mining agents.
Machine agent 426 is a process that runs in the background and performs a specified operation at predefined times or in response to certain events. In particular, machine agent 426 receives and responds to coordination requests from data mining agents, which allows coordination of the local computer system upon which the machine agent resides (computer system 420 N in this case) with other computer systems. Machine agent 426 monitors the configuration, utilization, processing load, and other parameters of the local computer system and can respond to requests requiring such information. Machine agent 426 can also launch data mining agents, such as data mining agents 428 A- 428 Z, if necessary to respond to requests for migration of data mining processing tasks to the local computer system.
An exemplary data flow diagram of processing performed by a data mining agent 500 is shown in FIG. 5 . Data mining agent 500 includes real time processing 502 , tuning and/or adaptation processing 504 , and user/system goal assessment 506 . Data mining agent 500 accepts input data 508 and performs real time processing 502 on the data to generate output data 510 . Input data 508 typically includes data such as data mining model training data, data mining model training parameters, data mining prediction data, and data mining prediction parameters, which is obtained from data sources such as proprietary and public data sources, users of the data mining system, and predefined parameters. Input data 508 may also include system observation data, such as machine CPU usage/load data. Real time processing 502 typically includes processing such as data mining model building, data mining model scoring, and data mining prediction/recommendation generation. Output data 510 typically includes data such as trained data mining models, scored data mining models, and data mining predictions and recommendations. Input data 508 is received from, and output data 510 is transmitted to, environment 512 . Environment 512 includes users of data mining processing services, sources of data mining data, other data mining systems with other data mining agents, etc.
User/system goal assessment processing 506 involves monitoring input data 508 to determine goals that users of data mining processing are attempting to achieve and how well those goals are being achieved by, in particular, other data mining systems with other data mining agents that are included in environment 512 . In addition, User/system goal assessment processing 506 monitor how well data mining agent 500 is achieving the goal of the data mining processing being performed by data mining agent 500 . By monitoring these factors, user/system goal assessment processing 506 allows data mining agent 500 to recognize goals that are not being achieved, whether by other data mining systems with other data mining agents or by data mining agent 500 itself. Tuning and/or adaptation processing 504 provides data mining agent 500 with the capability to respond when it determines that goals are not being achieved by other data mining agents or by data mining agent 500 itself. If the goals are not being achieved by other data mining systems, tuning and/or adaptation processing 504 can coordinate with the other data mining systems to migrate processing of data mining processing tasks from those systems to data mining agent 500 for processing. Likewise, if the goals are not being achieved by data mining agent 500 , tuning and/or adaptation processing 504 can coordinate with other data mining systems to migrate processing of data mining processing tasks from data mining agent 500 to the other data mining systems.
A data flow diagram of data mining agents selecting tasks to process is shown in FIG. 6 . As shown in FIG. 6 , there are a plurality of data mining agents, such as data mining agents 602 A- 602 N. These data mining agents are software components that are present on one or more computer systems, such as servers. Data mining agents 602 A-N are typically distributed among the computer systems. One form of communication among data mining agents 602 A- 602 N is provided by mining object repository (MOR) 604 , which serves as a central repository for data mining objects that is accessible by all data mining agents. In particular, MOR 604 includes one or more request queues, such as request queue 606 A- 606 X. Each request queue contains requests for data mining processing received directly or indirectly from data mining users. Request queues 606 A- 606 X may be organized in any way desired. For example, request queues 606 A- 606 X may be organized according to data mining users, types of data mining processing requested, priority levels of the requests, etc. The received requests for data mining processing are typically queued in a first-in-first-out (FIFO) arrangement. However, any request queue organization and any queueing arrangement is contemplated by the present invention. In addition, the MOR 604 is a logical entity and may itself be distributed to provide reliability and fault tolerance. Again, the present invention contemplates any arrangement or distribution of the MOR.
Each data mining agent, such as data mining agent 602 A, includes a plurality of processes/threads, such as peek at queue process 608 A and operation thread 610 A. The peek at queue processes 608 A- 608 N of data mining agents 602 A- 602 N communicate with request queues 606 A- 606 X and examine the queued requests for data mining processing contained therein. The peek at queue processes 608 A- 608 N select requests for data mining processing that are to be processed by each associated data mining agent as shown in FIG. 7 .
A data flow diagram of a data mining processing task request selection process 700 of a data mining agent is shown in FIG. 7 . FIG. 7 is best viewed in conjunction with FIG. 6 . Process 700 begins with requests for data mining processing being submitted to request queues 606 A- 606 X, as described above. In step 704 , a peek at queue process, such as peek at queue process 608 A of data mining agents 602 A, examines the queued requests for data mining processing contained therein. Typically, peek at queue processes 608 A is proactive, that is, the process actively examines request queues 606 A- 606 X looking for suitable requests to handle. In step 706 , peek at queue process 608 A determines if its associated data mining agent, data mining agent 602 A, is capable of processing each particular request. In step 708 , if peek at queue process 608 A determines that its associated data mining agent, data mining agent 602 A, is capable of processing a particular request, then peek at queue process 608 A accepts the request for processing and dequeues that request from the request queue in which it is contained. Steps 706 and 708 are performed repeatedly, with peek at queue process 608 A examining any accepted requests until it determines that data mining agent 602 A cannot handle any more requests. In step 710 , data mining agent 602 A processes the accepted requests.
A flow diagram of a process performed by step 706 , shown in FIG. 7 , in which peek at queue process 608 A determines if its associated data mining agent, data mining agent 602 A, is capable of processing each particular request, is shown in FIG. 8 . The process of step 706 begins with step 706 - 1 , in which it is determined whether the data mining agent supports the algorithm or algorithms that are required to process the particular request for data mining process being examined. For example, there may be data defined in, or associated with, the data mining agent, which defines the algorithms that are supported by the data mining agent. Likewise, the request for data mining processing may include data that defines, explicitly or implicitly, one or more algorithms that must be performed in order to perform the requested processing. An example may include XML data stored in the data mining agent that defines the algorithms supported by the data mining agent and XML data in the request for data mining processing that defines the algorithms that are required to process the request. In this case, a simple comparison of the XML definitions should suffice to determine whether the data mining agent supports the algorithm or algorithms that are required to process the particular request for data mining process being examined. If the request for data mining processing includes data that implicitly defines the algorithms that must be performed in order to perform the requested processing, a more complex process must be performed in order to determine whether the data mining agent supports the algorithm or algorithms that are required to process the particular request for data mining process being examined.
If, in step 706 - 1 , it is determined that the data mining agent does not support the algorithm or algorithms that are required to process the particular request for data mining process being examined, then the process of step 706 continues with step 706 - 2 , in which it is determined that the local computer system cannot process the particular request being examined. If, in step 706 - 1 , it is determined that the data mining agent does support the algorithm or algorithms that are required to process the particular request for data mining process being examined, then the process of step 706 continues with step 706 - 3 , in which it is determined whether the computer system upon which the associated data mining agent resides is currently busy and thus unavailable to accept additional processing. The definition of busy may be adjusted as desired. For example, a computer system may be defined as busy if it is performing any processing at all. On the other hand, a computer system may be defined as busy only if the available idle time of the computer system is less than some predefined or some dynamically calculated threshold. Likewise, in an embodiment in which one or more computer systems have more than one processor, the busy condition of each processor may be used instead.
An enhancement to step 706 - 3 is to determine the busy condition of the local computer system relative to other computer systems that may be utilized, rather than absolutely. For example, it may be determined whether the local computer system is more or less busy than other computer systems that might process the request. If other computer systems are more busy, then it may be determined, in step 706 - 3 , that the local computer system is relatively not busy. Conversely, if other computer systems are less busy, then it may be determined, in step 706 - 3 , that the local computer system is relatively busy. The relative busy conditions of the involved computer systems may be determined based on a variety of factors. For example, the processing load on each computer system may be considered, along with the processing speed of each computer system. The involved computer systems may exchange messages indicating these and other parameters, which may be compared by the data mining agents on each computer system. For example, each involved computer system may transmit a message in XML format, which may then be compared by the data mining agents on each computer system to determine the relative busy conditions of the involved computer system. The determinations may be made based on different algorithms, parameters, or thresholds by the various data mining agents. Thus, different data mining agents may generate different determinations of relative busy conditions.
However the determination of the busy condition of the local computer system is made, if, in step 706 - 3 , it is determined that the local computer system is busy, then the process of step 706 continues with step 706 - 4 , in which it is determined whether the local computer system is the first computer system that will become available for additional processing. The data mining agent first estimates the time to availability of the computer system upon which it resides. This estimate is performed based on factors such as estimated completion times of the processing jobs currently running on the computer system upon which the data mining agent resides. Each processing algorithm, such as data mining algorithms and others, provides estimates of completion times and also provides regular updates to those estimates. After the data mining agent has produced an estimate of the availability of the computer system upon which it resides, the data mining agent then exchanges estimates with other data mining agents and determines its availability relative to other data mining agents. If, in step 706 - 4 , it is determined that the data mining agent is not the first, or is not among the first number, of data mining agents that will become available, then the process of step 700 continues with step 706 - 2 , in which it is determined that the local computer system cannot process the particular request being examined.
If, in step 706 - 4 , it is determined that the data mining agent is the first, or is among the first number, of data mining agents that will become available, then the process of step 700 continues with step 706 - 5 . Likewise, if in step 706 - 3 , it is determined that the local computer system is not busy, then the process of step 706 continues with step 706 - 5 . In step 706 - 5 , it is determined whether the local computer system will be able to complete the requested processing in the allotted time. The request for data mining processing that is being examined may include time allocation information indicating a time that the processing must be completed or a total amount of processing time to be allocated to the task. The data mining agent generates an estimate of the time to completion of the task if the processing were performed on the computer system upon which the data mining agent resides. This estimate is then compared with the time allocation information included in the request for data mining processing. If it is determined that the local computer system will be able to complete the requested processing in the allotted time, then process 700 continues with step 706 - 6 , in which it is determined that the local computer system can process the particular request being examined. If it is determined that the local computer system will not be able to complete the requested processing in the allotted time, then process 700 continues with step 706 - 2 , in which it is determined that the local computer system cannot process the particular request being examined.
If no data mining agent accepts a request for data mining processing within a defined time limit, a timeout response may be transmitted to the entity that issued the request, the requestor. The time limit may be defined in the processing request itself, or it may be defined by a default value for the system MOR, or the particular request queue in which the processing request is queued. The timeout response allows the requester to perform alternate or error processing in the event the processing request is not accepted for processing.
An important feature of the present invention is the mobility of data mining processing from data mining agent to other agents and from one computer system to another. In particular, one or more data mining processing tasks that are being processed may be migrated to other computer systems under certain circumstances. For example, a computer system upon which a data mining agent resides may become overloaded, which would result in some or all of the tasks being processed by that computer system to be completed late or not completed at all. In this situation, the data mining agent, which is monitoring its environment, will detect the overload condition and may transfer the data mining processing task that it is processing to another computer system.
A flow diagram of one embodiment of a data mining processing task migration process 900 is shown in FIG. 9 . The process begins with step 902 , in which a local data mining agent determines that the local computer system, upon which the local data mining agent resides, and which is processing the current task of the local data mining agent, is overloaded. The local data mining agent may determine overloading in a number of ways, but typically, processor (CPU) utilization is the preferred measure. For example, a threshold CPU utilization may be set, such as if the CPU utilization is greater than a predefined percentage for a predefined number of seconds, then an overload condition exists.
In step 904 , the local data mining agent queries other computer systems to determine if any other computer systems can complete the current task of the local data mining agent more quickly than the local computer system. To do this, the local data mining agent generates an estimate of the time the task would take to complete if the processing were performed on the local computer system. This estimate involves estimating the amount of processing that must be performed to complete the data mining processing task and an estimate of the CPU utilization available to process the data mining processing task. The time to complete processing of the data mining processing task may then be estimated based on the estimate of the amount of processing that must be performed, the estimate of available CPU utilization, and the speed of the CPU. The data mining agent also transmits queries to other computer systems. Typically, the queries request from other data mining agents information such as the speeds of the computer systems upon which the other data mining agents reside and estimates of CPU utilization that the computer systems upon which the other data mining agents reside could provide to process the data mining processing task. In some cases, there may not be any data mining agents running on a computer system that receives a query, even though the computer system is available for performing data mining processing. In this situation, other software on the computer system can respond to the query.
In step 906 , the local data mining agent determines whether another computer system could complete the data mining processing task faster than the local computer system. To do this, the local data mining agent computes estimates of times to complete the data mining processing task based on the amount of processing that must be performed to complete the data mining processing task, the speed of the other computer systems, and estimates of CPU utilization of the other computer systems.
Alternatively, the queries transmitted to the other data mining agents may include information relating to the amount of processing that must be performed to complete the data mining processing task. The other data mining agents would then compute estimates of times to complete the data mining processing task based on the amount of processing that must be performed to complete the data mining processing task, the speed of the other computer systems, and estimates of CPU utilization of the other computer systems. The responses to the queries would include these completion time estimates.
In either case, the local data mining agent then adds estimates of the time it would take to migrate the data mining processing task to another computer system to the estimated completion times for the other computer systems. The local data mining agent then compares the estimated completion time for the local computer system with the estimated completion times for the other computer systems to determine whether another computer system could complete the data mining processing task faster than the local computer system. If, in step 906 , the local data mining agent determines that the computer system upon which it resides could complete the data mining processing task faster than any other computer system, then process 900 ends and the data mining processing task is not migrated.
If in step 906 , the local data mining agent determines that another computer system could complete the data mining processing task faster than the local computer system, then process 900 continues with step 908 , in which the local data mining agent selects the computer system with the fastest completion time and reserves that computer system for migration of the data mining processing task. If there are one or more data mining agents running on the selected computer system, one of those data mining agents may receive and accept the reservation. Alternatively, other software on the selected computer system may receive and accept the reservation, whether data mining agents are running on the selected computer system or not. If there are no data mining agents running on the selected computer system, then the software that receives and accepts the reservation is responsible for launching a data mining agent to handle the data mining processing.
In step 910 , the local data mining agent interrupts the processing of the data mining processing task that is being performed on the local computer system. The data mining processing task is checkpointed, that is, all input data, processing state information, and output data that is required to resume processing of the data mining processing task is saved. In step 912 , the local data mining agent enqueues a “continueBuild” request in a request queue that serves the selected computer system, to which the data mining processing task is migrating. The continueBuild request typically references the checkpointed data that is needed to resume processing of the data mining processing task. When a data mining agent on the computer system to which the data mining processing task is migrating dequeues the continueBuild request, the reference to the checkpointed information is used to actually transfer the checkpointed information to the computer system to which the data mining processing task is migrating. Alternatively, the checkpointed information may be included with the continueBuild request.
A flow diagram of one embodiment of a data mining processing task migration process 1000 is shown in FIG. 10 . In this embodiment, the data mining agents communicate with each other on a regular basis, so that computer system utilization can be easily coordinated among the data mining agents. Process 1000 begins with step 1002 , in which a local data mining agent determines that the local computer system, upon which the local data mining agent resides, and which is processing the current task of the local data mining agent, has a high load relative to other computer systems. The local data mining agent may determine load in a number of ways, but typically, processor (CPU) utilization is the preferred measure. Data mining agents communicate loading information with each other on a regular basis. In particular, it may determined that the processing load of the local computer system is high relative to the processing loads of other computer systems by determining a processor utilization of the local computer system, determining processor utilizations of the other computer systems, and determining that the processor utilization of the local computer system is greater than a predefined amount higher than the processor utilization of the other computer systems.
In step 1004 , the local data mining agent determines the remaining cost of completing processing of the data mining processing task on the local computer system. The cost of completing processing may be based solely on the time it would take to complete processing, or it may be based on additional factors, such as actual costs that must be paid for use of computing equipment, etc. In order to determine the time it would take to complete processing, the local data mining agent generates an estimate of the time the task would take to complete if the processing were performed on the local computer system. This estimate involves estimating the amount of processing that must be performed to complete the data mining processing task and an estimate of the CPU utilization that will be used to process the data mining processing task. In addition, the local data mining agent may estimate other factors, such as actual costs that must be paid for use of computing equipment, etc.
In step 1006 , the local data mining agent solicits bids for completing processing of the data mining processing task from other computer systems. Typically, the requests for bids transmitted to the other data mining agents include information relating to the amount of processing that must be performed to complete the data mining processing task. The other data mining agents would then submit bids to the local data mining agent. The bids would include estimates of the costs of completing the data mining processing task on each of the other computer systems. In order to generate a bid, a data mining agent would compute estimates of costs to complete the data mining processing task that are based on the amount of time that is needed to complete the migrated task and may also be based on other factors, such as the cost of processing on the computer system. The time to complete the migrated task includes both the time needed to complete the processing and the time needed to migrate the task from one computer system to another. The time needed to complete the processing is based on the amount of processing that must be performed to complete the data mining processing task, the speed of the other computer systems, and estimates of CPU utilization of the other computer systems.
In some cases, there may not be any data mining agents running on a computer system that receives a request for a bid, even though the computer system is available for performing data mining processing. In this situation, other software on the computer system can generate and transmit the bid.
In step 1008 , the local data mining agent determines whether another computer system has a bid that is lower than the cost to complete the data mining processing task on the local computer system. To do this, the local data mining agent compares the determination of the cost of completing processing of the data mining processing task on the local computer system with the bids received from the other computer systems. If any of the received bids are significantly lower than the cost of completing processing of the data mining processing task on the local computer system, the local data mining agent migrates the remaining processing of the data mining processing task to the lowest bidder among the other computer systems. In order to carry out the migration, the local data mining agent interrupts the processing of the data mining processing task that is being performed on the local computer system. The data mining processing task is checkpointed, that is, all input data, processing state information, and output data that is required to resume processing of the data mining processing task is saved. The data mining agent enqueues a “continueBuild” request in a request queue that serves the computer system to which the data mining processing task is migrating. The continueBuild request typically references the checkpointed data that is needed to resume processing of the data mining processing task. When a data mining agent on the computer system to which the data mining processing task is migrating dequeues the continueBuild request, the reference to the checkpointed information is used to actually transfer the checkpointed information to the computer system to which the data mining processing task is migrating. Alternatively, the checkpointed information may be included with the continueBuild request.
It is important to note that while the present invention has been described in the context of a fully functioning data processing system, those of ordinary skill in the art will appreciate that the processes of the present invention are capable of being distributed in the form of a computer readable medium of instructions and a variety of forms and that the present invention applies equally regardless of the particular type of signal bearing media actually used to carry out the distribution. Examples of computer readable media include recordable-type media such as floppy disc, a hard disk drive, RAM, and CD-ROM's, as well as transmission-type media, such as digital and analog communications links.
Although specific embodiments of the present invention have been described, it will be understood by those of skill in the art that there are other embodiments that are equivalent to the described embodiments. Accordingly, it is to be understood that the invention is not to be limited by the specific illustrated embodiments, but only by the scope of the appended claims. | 4y
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