TWINSHEET THERMOFORMING APPARATUS AND METHOD

摘要

A simultaneous twinsheet thermoforming system having a carousel rack (102) to simultaneously move two sheets (104, 106) of thermoplastic together through a heating station (202) and a forming station (204). The two thermoplastic sheets are vertically disposed on upper and lower tiers of the rack. The single heating station includes vertically disposed upper and lower ovens (120, 122), which both sheets pass through simultaneously. The ovens each include upper (124a-b) and lower heating platens (126a-b), the lower platens being movable to accommodate for sagging thermoplastic. The forming station includes upper and lower vacuum molds (108, 110) that are movable from an open position to a dlosed position. In the open position, the two sheets 10 are moved in between the mold faces. The molds are driven together to contact the sheets and simultaneously form the two sheets to the two molds. At least one of the two molds is further moved to establish contact betwween at least portions of the two sheets, thus fusing them together.