Abstract: A differential pressure thermoforming machine has a female mold with a female mold cavity, and an opposing mold, with a mold closing portion cooperable therewith. A foam injection head is perimetrally separated from the mold closing portion and is provided on the opposing mold. When the molds are initially closed, a differential pressure is created in the molds to cause the heated plastic sheet to move into contact with the mold cavity and form a configured pocket in the sheet. Mechanism is provided for releasing the plastic sheet from the carriage in which it has been moved between the molds, after the molding operation, to the cavity in the female mold, after which the molds are restored to spread-apart position.

Abstract: Contact heater station mechanism for use in a thermoforming machine for particularly forming thermoplastic synthetic plastic and superplastic metal alloy sheets into shapes, such machines having a sheet transfer station, a heating station, and a forming station with relatively movable mold parts, and providing a circuit for sheet carrying carriages which index individually clamped sheets from one station to another cyclically in a path of travel. The mechanism includes platens mounted on the machine frame at the heating station to move toward and away from the path of travel of the carriages and sheets. A heater carrrier for elongate electrical resistance heaters carries a contactor plate, and is rigidly mounted to each platen in a manner to permit universal thermal expansion of the carrier and plate with respect to the platen.