Abstract: Thermoforming equipment includes a solid state sensor adapted to determine when a sheet of thermoplastic material has been clamped between a forming mold and a heating platen. Clamping force is provided by a cutter blade carried by said mold around the periphery thereof. Electronic control circuitry responsive to the sensor maintains the thermoplastic sheet in clamped relation without being severed by the blade. After the thermoplastic sheet has been formed into an article defined by the mold, the mold and platen are permitted to continue to close beyond the point sensed by the sensor, permitting the blade to penetrate the sheet and sever the formed article therefrom.

Abstract: Plastic web advancing apparatus for thermoforming equipment wherein the plastic web is indexed by being pulled between a three-roller arrangement located on the downstream side of a forming press. The rollers are driven by a stepping motor for intermittent indexing of the web through the press. Upstream of the forming press, the web is threadedly received between a pair of relatively movable clamping rollers which upon cyclical opening of the forming press are used to tension and feed the web in conjunction with the three-roller arrangement on the downstream end of the press. Upon closing of the press, the upstream clamping rollers are moved away from each other to release the web, enabling the web to shift and diagonally position its edges in alignment with the forming dies in the press.