Abstract: A thermoforming apparatus for forming sheets of sheet plastic onto a substrate in which a retractable substrate heater is able to be positioned over a substrate loaded into the press and energized while a plastic sheet is being heated in an oven included in the thermoformer apparatus. The plastic sheets are cut from a strip pulled from a roll of sheet material, the roll supported for side to side movement and driven by a servomotor responsive to error signals generated by a strip edge sensor to compensate for wandering of a strip edge to thereby insure accurate location of plastic sheets cut from the unwound strip.

Abstract: A thermoforming apparatus for forming sheets of sheet plastic onto a substrate in which a retractable substrate heater is able to be positioned over a substrate loaded into the press and energized while a plastic sheet is being heated in an oven included in the thermoformer apparatus. The plastic sheets are cut from a strip pulled from a roll of sheet material, the roll supported for side to side movement and driven by a servomotor responsive to error signals generated by a strip edge sensor to compensate for wandering of a strip edge to thereby insure accurate location of plastic sheets cut from the unwound strip.

Abstract: Adjustable clamping frames for rotary thermoforming machine have movable sets of clamp supporting members which are driven by selectively engageable drive units to carry out a size adjustment at a station in the thermoforming machine.

Abstract: A twin sheet thermoformer apparatus using hydraulic cylinders to draw the upper and lower platens together for uniform seam forming of the part. A flow divider insures uniform travel of each hydraulic cylinder. An adjustment mechanism enables simultaneous adjustment of the position of four locking shafts on one platen coupled to form locking shafts on the other platen preparatory to operation of the hydraulic cylinders. The adjustment mechanism includes nut members each threaded onto a locking shaft with a recirculating chain engaged with a sprocket on each nut member. Driving the chain enables simultaneous adjustment of each shaft to allow the platen positions to be quickly and accurately adjusted. An encoder generates signals corresponding to the lower platen travel caused by operation of the hydraulic cylinders, which are transmitted to the lower platen drive servo motor to drive the lower platen correspondingly.

Abstract: Apparatus and method for severing and stacking articles which have been differentially pressure formed in a sheet of thermoplastic material from the sheet. Apparatus is provided for moving the sheet in a horizontal path and relatively vertically moving opposed upper and lower trim dies into engagement with vertically opposite sides of the sheet to trim the articles from the sheet at a trim station. The articles free fall through an opening in the lower die and free fall to an underlying accumulator. The accumulator includes mechanism which is moveable from a stack forming position in the path of freely falling articles to receive and accumulate freely falling severed articles in a stack, and a releasing position in which a formed the stack is released for vertical free fall.