Forming arrangement for machines making receptacles out of thermoplastic material

Claim 1

An improved heat-forming molding machine for producing by deep drawing receptacles of thermoplastic material from plastic strips and sheets including means for feeding a plastic band into the mold cavity of the machine; the improvement comprising, a fixed mandrel; a mold having a mold cavity reciprocally movable relative to said fixed mandrel, said mandrel thereby moving into and out of said mold cavity, said mandrel and/or mold defining a forming chamber adapted to receive a plastic banderole, which forming chamber and mandrel have contours which substantially correspond to that of the mold cavity so that said mandrel has a substantially fixed transverse cross-sectional area with respect to the forming chamber and mold cavity to thereby define a narrow guide passage for the plastic banderole; said mandrel including a plurality of parts, a first number of these parts having transverse sections which remain fixed relative to said forming chamber and a second number of these parts have transverse sections which rotate relative to said forming chamber, the latter sections forming part of round or curved portions of the forming chamber, said rotatable transverse sections including suction channels for coacting and biasing the banderole against the rotatable parts of the mandrel to thereby impart an advancing motion to the banderole, said suction channels being in operative communication with a vacuum source.