Apparatus for the production of thinwalled containers or receptacles from a thermoplastic film or sheet

Claim 1

APPARATUS FOR THE PRODUCTION OF THIN-WALLED CONTAINERS FROM THERMOPLASTIC HEAT-FORMABLE MATERIAL, SAID APPARATUS COMPRISING: A BEARING TABLE; AT LEAST ONE INSERT BEING MOUNTED IN SAID BEARING TABLE AND BEING VERTICALLY MOVABLE WITH RESPECT THERETO; SAID INSERT HAVING AN ANNULAR PORTION BEING SUBSTANTIALLY HORIZONTAL AND EXTENDING AROUND THE PERIPHERY OF SAID INSERT; SAID ANNULAR PORTION TERMINATING IN A VERTICAL SIDE PORTION OF SAID INSERT; A FIRST VERTICALLY DISPLACEABLE SHAPING PISTON EXTENDING THROUGH THE CENTER OF SAID INSERT; SAID FIRST PISTON BEING ADAPTED TO MOVE VERTICALLY WITH RESPECT TO SAID INSERT; AT LEAST ONE OPENING EXTENDING THROUGH THE TOP OF SAID INSERT AND PROVIDING A PASSAGEWAY FOR THE ADMISSION OF COMPRESSED AIR THERETHROUGH; A MOLD CAVITY LOCATED VERTICALLY ABOVE AND IN ALIGNMENT WITH SAID INSERT; SAID MOLD CAVITY BEING MOUNTED IN A VERTICALLY MOVABLE MOLD SUPPORT FOR VERTICAL MOVEMENT THEREWITH; SAID MOLD CAVITY BEING FURTHER SLIDABLY MOUNTED IN SAID MOLD SUPPORT FOR VERTICAL MOVEMENT RELATIVE THERETO; SAID MOLD CAVITY BEING NORMALLY BIASED INTO A LOWER POSITION WITH RESPECT TO SAID MOLD SUPPORT; A CUTTING RING EXTENDING AROUND THE CIRCUMFERENCE OF THE MOLD CAVITY AND BEING MOUNTED ON THE BOTTOM OF SAID MOLD SUPPORT; SAID CUTTING RING HAVING AN OPENING SUBSTANTIALLY CONFORMING TO, BUT BEING SLIGHTLY LARGER THAN THE CONFIGURATION OF THE VERTICAL SIDE PORTION OF THE INSERT; A SECOND VERTICALLY CAVITY FOR MOVEMENT WITH RESPECT TIONED IN SAID MOLD CAVITY FOR MOVEMENT WITH RESPECT THERETO AND BEING COAXIALLY ALIGNED WITH SAID FIRST PISTON; MEANS FOR MOVING SAID MOLD CAVITY, AND SAID SECOND PISTON DOWNWARDLY INTO ENGAGEMENT WITH A SHEET TO BE FORMED WHEREBY SAID SHEET IS FIRMLY CLAMPED BETWEEN SAID MOLD CAVITY AND SAID HORIZONTAL PORTION OF SAID INSERT; SAID SECOND PISTON BEING YIELDABLY BIASED INTO ENGAGEMENT WITH THE TOP OF SAID SHEET TO BE FORMED; MEANS FOR MOVING SAID FIRST PISTON UPWARDLY TO MOVE A PORTION OF SAID SHEET UPWARDLY AGAINST THE ACTION OF SAID SECOND PISTON TO MECHANICALLY PRE-STRETCH SAID SHEET AND PARTIALLY PREFORM SAID CONTAINER; SAID OPENING PROVIDING FOR THE ADMISSION OF COMPRESSED AIR INTO THE PARTIALLY PREFORMED CONTAINER TO EXPAND SAME COMPLETELY AGAINST THE SIDES OF THE MOLD CAVITY; MEANS FOR MOVING SAID INSERT AND SAID MOLD CAVITY UPWARDLY WITH RESPECT TO SAID MOLD CAVITY SUPPORT AND SAID CUTTING RING WHEREBY THE FORMED CONTAINER IS SHEARED FROM SAID SHEET; AND MEANS FOR MOVING SAID MOLD, SAID MOLD SUPPORT, AND SAID CUTTING RING UPWARDLY WITH RESPECT TO SAID MOLD INSERT SO AS TO ALLOW THE FORMED CONTAINER TO BE EJECTED FROM THE MOLD TABLE.