This invention relates, generally, to innovations and improvements in package-forming machines known in the packaging art as Chub machines which form tubular packages which are gathered and clipped at opposite ends.
An early form of the Chub machine is disclosed in U.S. Pat. No. 2,831,302 issued Apr. 22, 1958. Improvements and innovations on the original Chub machine have been made over the years, a number of which have formed the subject matter of additional U.S. patents, including: U.S. Pat. Nos. 3,324,621 dated Jun. 13, 1967; 3,795,083 dated Mar. 5, 1974; 3,380,226 dated Apr. 30, 1968; 4,085,778 dated Apr. 25, 1978; 4,223,508 dated Sep. 23, 1980 and 4,939,885 dated July 10, 1990. These additional patents have been assigned to the assignee of the present invention. In addition to disclosures in the foregoing patents, Chub package forming machines are in wide use in this country and described in printed service manuals, and have been commercially available from The Kartridg Pak Co. of Davenport, Iowa for a number of years. Chub machines can be used for packaging many flowable or extrudable materials. For example, various edible products such as ground meat, cheese, liver sausage, butter, ice cream and cookie dough have been packaged utilizing the Chub machines. Inedible products have also been packaged utilizing the Chub machines including explosives.
In operation, a Chub machine continuously unwinds and forms a tube from a roll of film, fills the tube with a flowable material, gathers or constricts at regular intervals short lengths of the filled tubing, applies a pair of closure clips to each gathered length of tubing, and severs the gathered or constricted material between the individual clips in a pair thereof.
In operation, the Chub machines also unwind two strands of wire from coils or reels and cut off predetermined lengths from the ends of the wire so as to provide the clips which are then suitably formed and constricted in pairs to each gathered length of tubing.
The primary operating components or elements of a Chub machine are: the tube-forming mechanism whereby a web of film is withdrawn from a supply roll, folded over around a hollow mandrel into a tube and heat or otherwise sealed; a product metering pump which injects flowable product through the mandrel out into the tube; a tube or film feed mechanism which continuously feeds the tube over and away-from the mandrel; a voider which flattens or collapses short lengths of the filled tube at predetermined intervals; and a clipping head which applies a pair of spaced clips to the voided and gathered tube and severs the tube intermediate the clips. Heretofore, these operating components or sub-assemblies have been manually pre-set by the operator so that their combined operation is properly coordinated. Settings will vary depending on various factors including type of product, seal-forming characteristics of the film and package size. During a particular run it may become necessary to make adjustments in the various settings. Some adjustments can be made during a run while others require either slowing or shutting down the Chub machine. When a Chub machine has been running on one product it is usually necessary to reset the machine during down-time in order for it to package a different product.
It will be apparent that pre-setting, adjusting and re-setting a Chub machine are time-consuming and require skill on the part of the operator. Heretofore, Chub machines offered independent controls of operating components without linkage. If one component or element of a machine was changed, all the remaining components (motors, timers, etc.) normally had to be changed manually with trial and error techniques requiring considerable operator skill. The present invention links the elements together and places the various rates and set points in memory for immediate recall as needed.
In accordance with the present invention, Chub machines have been provided with automatic control and monitoring systems which by means of microprocessors or computers are operatively interconnected with servo actuators which are in turn operatively connected with the various machine operating components, allow the machines to be automatically pre-set, fine-tune adjusted and re-set using data stored in the memory systems of the microprocessors.
Accordingly, the object of the invention, generally stated is the provision of the Chub packaging machines which are automatically controlled and monitored so as to minimize manual setting or adjustment of the various operating components either on start-up of a run, during the course of a run, or on change-over for packaging a different product.
An important object of the invention is the provision of Chub machines with automatic controls and monitoring systems which are readily set and adjusted, which have stored data memory capabilities and which include an operator interface membrane panel with video display which allows the operator to monitor, set, observe and adjust the various functions of the machine either while idle or running.