The present invention relates to tools used for industrial, public utility, and heavy duty applications. More precisely, the present invention relates to a large, self-forming socket tool for heavy duty use for the construction industry, steam, water and sewage piping, large conduits, earth moving equipment, and the like.
Many of today's machines are assembled using bolts, nuts, wing-nuts, screws, and similar fasteners. In order to work with such fasteners, wrenches and socket sets are common required tools. Unfortunately, there are a large variety of such fasteners. Even for a standard hex-head bolt, there are numerous English and metric sizes. For a craftsman to be fully prepared to work with such a myriad of bolts, he must maintain a large assortment of socket sizes, and sometimes that assortment must include different socket shapes. Having to locate the correct size socket-head and switching between different sized socket-heads to use in conjunction with a wrench or power tool are cumbersome and inconvenient tasks.
As a result, there have been developments into sockets that self-adjust to the particular size and shape of the bolt head or nut. For example, U.S. Pat. No. 3,858,468 to Pasbrig, et al. discloses a clamping tool having a housing with a chamber therein and an opening at one end. A plurality of bundled, square shape bars are disposed in the chamber, wherein the bars are individually displaceable inward of the housing against the spring action of a pad. As the tool is pushed over the head of a bolt or a nut, the bars in contact retract into the pad and surrounding the nut or bolt head thereby gripping the part. The bolt head or nut can then be torqued as necessary.
U.S. Pat. No. 3,698,267 to Denney discloses a fastener actuator having a plurality of fastener engaging elements, wherein the elements are bundled and slide independently and longitudinally into and out of the actuator to accommodate a bolt head, nut, or slotted screw-head. Each element has a rectangular cross-section in order to grip the flat sides of a standard bolt head, or to fit into the flat walls of a slotted screw-head.
U.S. Pat. No. 4,887,498 to Zayat discloses a tool for form engaging and turning components such as nuts, bolts, and screws. In its basic form, the Zayat device includes a chamber which in turn supports a bundle of pins each of which is adapted to slide farther upwardly into the chamber when the lower pin end contacts the component at the lower end of the housing. Each of the pins has flat sides and sharp corners in order to engage a nut either by the flat sides or the sharp corners. U.S. Pat. No. 5,460,064 to Zayat shows in one embodiment headless dowels 52 to hold a frame, as seen in FIG. 6.
U.S. Pat. Nos. 5,791,209 and 5,622,090 to Marks show a universal socket tool. U.S. Pat. No. 5,937,715 to Lin teaches a socket tool with a two-piece threaded pin assembly. U.S. Pat. No. 5,806,385 to Schupp discloses a universal socket with a two-piece pin including a “pin retaining means 44.” Based on the disclosure, the means are shown as rivet heads or pressed on collars. There is no provision for disassembly of the pins from the device. U.S. Pat. No. 6,023,999 to Cho shows a universal socket with pins press fitted into a block shaped frame.
U.S. Pat. No. 3,349,655 to Locke discloses an adjustable tool for installing or removing fasteners of various sizes, comprising of a bundle of rods surrounded by a girdle and resiliently mounted in a chuck. The rods may be pressed into conformity with the head of a fastener, and upon the application of torque to the chuck, the girdle constricts and accordingly torque is applied to the fastener through the rods. Each of the rods has flat sides and the bundle of rods are tightly packed.
U.S. Pat. No. 1,529,605 to Muncey discloses a wrench having closely packed and individually extendable rods that engage a bolt head or nut. Each of the extendable pins has a rectangular shaped cross-section.
The foregoing art teach of a method and structures for gripping a three dimensional object by using polygonal shaped pins closely packed in parallel in a bundle and independently displaceable longitudinally to accommodate the height dimension and contours of the device to be gripped. This construction has been used in a vise as well, as disclosed, for example, in U.S. Pat. No. 2,754,708 to Peterson. In Peterson '708, groove 60 is shown with a slip ring 62 fitted. The end of portion 58 is not tapered; therefore the split ring must only be installed from the side.
There have been other attempts at self-adjusting sockets. For instance, U.S. Pat. No. 5,157,995 to Nogues discloses a multiple socket wrench comprised of several coaxially disposed socket members housed within each other. The sockets are spring loaded and each has a reduced diameter towards the outer end that prevents the abutting sockets contained therein from falling off as a result of gravity or the spring force of the different spring members associated with each one of the sockets. Each spring urges each socket outwardly, and the springs of the sockets that are smaller than the head of the bolt or screw being matched are overcome and retracted, thereby automatically matching the correct size socket to the head of the bolt or nut. U.S. Pat. No. 2,711,112 to Durand discloses another multiple socket wrench having coaxially aligned sockets of varying sizes organized on the ratchet in a concentric arrangement.
For some applications it is required to have a very large size socket tool. One such application is for municipal water valves. These valves are actuated through a sometimes irregularly shaped square valve head that is 2 inches on each side. This use requires a socket that is about 3 inches between flats for a hexagonal interior socket. Another such application is for fire hydrants, which use an odd shaped valve head. Other chemical and industrial applications are also suited for a large universal socket tool. Such a large universal socket size leads to special needs that the forgoing devices cannot provide.
One such attempt at addressing such a need is disclosed in U.S. Pat. Nos. 5,746,416 and 5,794,644 to Paylor. The device is a slotted adapter at one end to register with a water main valve for turning the valve. A torquing handle may be attached to the adapter for applying torque from a location remote from the adapter. However, there is still a need for a socket tool that has sufficient strength and bulk to address the needs of such industrial applications unsuited for the conventional socket tool.