Rotary machine for the combined automatic vacuum- and pressure-forming of continuous thermoplastic bands

Claim 1

IN A ROTARY MACHINE FOR THE COMBINED AUTOMATIC VACUUM AND PRESSURE FORMING A CONTINUOUS THERMOPLASTIC BANDS OR SHEETS INCLUDING A ROTATABLE DRUM, A PLURALITY OF PERFORATED MOLDS AROUND THE PERIPHERY OF SAID DRUM, HEATING MEANS NEAR THE PERIPHERY OF SAID DRUM, MEANS FOR FEEDING A CONTINUOUS STRIP OF THERMOPLASTIC SHEET MATERIAL ONTO THE PERIPHERY OF SAID DRUM AND IN THE VICINITY OF SAID HEATING MEANS, SUCTION MEANS IN COMMUNICATION WITH THE PERFORATIONS OF SAID MOLDS FOR DRAWING THE SHEET MATERIAL INTO ENGAGEMENT WITH THE MOLD SURFACES, VALVE MEANS CONTROLLING SAID SUCTION MEANS AND OPERATIVE UPON ROTATION OF SAID DRUM TO PLACE SAID SUCTION MEANS IN COMMUNICATION WITH SAID MOLDS SUCCESSIVELY AS THE RESPONSIVE MOLDS ARE REVOLVED AND SEALING MEANS ENGAGEABLE WITH THE SHEET MATERIAL TO FORM AN AIRTIGHT SEAL WITH SAID DRUM AROUND EACH OF SAID MOLDS, THE IMPROVEMENTS COMPRISING FIRST COUPLING MEANS PROJECTING FROM SAID DRUM IN SPACED POSITIONS ALONG ITS PERIPHERY IN CORRESPONDENCE OF EACH OF SAID MOLDS, A PUNCH HAVING AN INITIAL POSITION SPACED RADIALLY FROM THE PERIPHERY OF SAID DRUM, FLUID OPERATED MEANS FOR SUCCESSIVELY SHIFTING SAID PUNCH INTO ENGAGEMENT WITH THE STRIP OF THERMOPLASTIC SHEET MATERIAL UPON EACH MOLD AND PRESSING THE SHEET INTO THE MOLD RADIALLY, SECOND COUPLING MEANS EXTENDING RADIALLY ON SAID PUNCH COACTING WITH SAID FIRST COUPLING MEANS ON SAID DRUM WHENEVER SAID PUNCH IS BEING SHIFTED INTO ENGAGEMENT WITH A STRIP OF THERMOPLASTIC SHEET MATERIAL UPON A MOLD AND GUIDING THE RADIAL MOVEMENT OF THE PUNCH INTO THE MOLD, SAID PUNCH WHILE INSERTED IN A MOLD BEING ENTRAINED BY SAID DRUM FOR A FRACTION OF ITS REVOLUTION, MEANS ASSOCIATED WITH SAID FLUID OPERATED MEANS FOR WITHDRAWING SAID PUNCH CLEAR OF SAID PUNCHED SHEET AND THE CORRESPONDING MOLD, AND SPRING MEANS PIVOTALLY CONNECTED TO SAID PUNCH FOR RETURNING THE PUNCH TO ITS INITIAL POSITION.