Abstract: An oscillating canopy is employed in the feeding of an elongate sheet of synthetic plastic material having articles, such as cups, for example, formed in the sheet, to a die which trims the articles from the sheet. The canopy has a downwardly concave curved upper portion upon which the sheet is supported by a series of rollers. The canopy is driven in forward and return strokes in pivotal movement about an axis located at a radial distance from the curved upper portion which is a greater distance from the discharge end of the curved upper portion than from the sheet receiving end so that tension is maintained on the sheet during the feeding stroke. The sheet-supporting rollers are mounted for rotation in one direction only, this direction being that in which the rollers can roll relative to the sheet on the return stroke of the canopy.

Abstract: In differential pressure synthetic plastics thermoforming machinery, mold support assemblies mounted on a frame have relative movement between a mold open and a mold closed position. Power operated mechanism is provided for axially moving at least the female mold support assembly, and the female mold on the assembly which carries a stripper element mounted for relative movement with the mold. Mechanism is provided for automatically latching the stripper element to the frame as the female mold moves toward mold closed position, and abutments are provided on the mold support assembly and latch for automatically unlatching it only after the female mold has withdrawn a predetermined distance in its movement toward mold open position.

Abstract: An indexing system for synthetic plastics molding machinery, wherein plastic web gripping drive elements are employed to feed a plastic web in planar indexing movements to the molds of the machine, utilizes a conventional pump driven hydraulic motor connected with the web gripping drive elements by drive transmission mechanism incorporating a brake for positively halting the web gripping elements in predetermined position. A stroke measuring control device driven by the drive transmission mechanism in a path of movement corresponding with the indexing moving of the web gripping elements first decelerates the movement of the web gripping elements and then positively halts them in a predetermined position. Alternatively, a photoelectric eye sensitive to the position of the web can stop the web.

Abstract: A trim press for severing cup-shaped articles from a sheet of thermoplastic material in which the articles have been integrally formed as by a vacuum forming operation. A horizontally reciprocable punch is driven to sever articles positioned in a stationary die by a linkage arranged to drive the punch at a relatively slow speed during the severing operation to achieve a smooth shearing separation of the relatively soft thermoplastic material. The sheet is fed into the die in step-by-step movement through vertical sheet guides fixedly mounted in a treadle which is reciprocated with the punch at a proportionate speed. A flexible sheet guide connected between the guides in the treadle and a fixed point on the machine frame flexes to accommodate reciprocation of the treadle while continuously guiding the sheet to the guides on the treadle. Feed fingers mounted on the treadle advance the sheet to the die in step-by-step movement synchronized with the stroke of the punch.

Abstract: A thermoforming machine having opposed mold platens includes a linkage system driven in cyclic movement by a single rotary cam to cyclically shift the platens between their open and closed position. The cam is driven by a variable speed motor which is controlled in a manner such that the rotary speed of the cam during different portions of a cam revolution may be set to a speed which is different than the rotary speed of the cam during other portions of each revolution. By adjusting the speed differential or by adjusting the angular extent of that portion of a revolution of the cam over which the different speed is maintained the time duration of any chosen portion of the cycle may be adjusted independently of the time duration of other portions of the cycle. The platens are mounted for reciprocatory movement upon a three-post frame.