Blow molding apparatus with blowmold exhaust means

Claim 1

APPARATUS FOR BLOW MOLDING A THERMOPLASTIC OBJECT COMPRISING IN COMBINATION SECTIONAL MOLD MEANS WHICH FORM, WHEN CLOSED, A CAVITY FOR FORMING A MOLDED THERMOPLASTIC OBJECT, DIE MEANS HAVING A MANDREL MEANS DISPOSED THEREIN IN COMMUNICATION AT A FIRST END THEREOF WITH A SUPPLY OF MOLTEN THERMOPLASTIC MATERIAL SO AS TO EXTRUDE FROM THE SECOND END THEREOF AN OPEN-ENDED TUBE OF THERMOPLASTIC MATERIAL INTO THE SPACE BETWEEN THE OPEN MOLD SECTIONS, SAID MANDREL AND DIE MEANS COMPRISING FIRST, SECOND AND THIRD CONCENTRIC ELONGATED CYLINDERS, SAID FIRST ELONGATED CYLINDER FORMING A FIRST ANNULUS IN COMMUNICATION WITH SAID CAVITY AT A FIRST END THEREOF AND SO EXTENDED AT THE SECOND END THEREOF TO FORM A FIRST CONDUIT OPERATIVELY CONNECTED TO A SOURCE OF A GASEOUS PRESSURE MEDIUM, SAID SECOND ELONGATED CYLINDER DISPOSED AROUND SAID FIRST ENLONGATED CYLINER AND SPACED APART THEREFROM SO AS TO FORM A SECOND ANNULUS AREA, SAID FIRST AND SECOND ELONGATED CYLINDERS BEING SO ADAPTED AS TO CLOSE EACH END OF SAID SECOND ANNULUS THEREBY FORMING A CLOSED EACH END BETWEEN SAID FIRST AND SECOND CYLINDERS, THEREBY INSULATING SAID FIRST ANNULUS, SAID THIRD ELONGATED CYLINDER DISPOSED AROUND SAID FIRST AND SECOND ELONGATED CYLINDERS AND SPACED APART THEREFROM SO AS TO FORM A THIRD ANNULUS, SAID THIRD ANNULUS BEING OPERATIVELY CONNECTED TO SAID SUPPLY OF THERMOPLASTIC MATERIAL AT A FIRST END THEREOF AND ADAPTED AT THE SECOND END THEREOF TO FORM SAID TUBE OF THERMOPLASTIC MATERIAL, SAID MOLD HALVES BEING PROVIDED WITH MEANS, WHEN CLOSED TO PINCH OFF SAID TUBE AT A POINT REMOTE FROM SAID DIE AND MANDREL MEANS AND TO CLOSE AROUND SAID MANDREL MEANS AT A POINT ADJACENT THEREOF AND FURTHER ADAPTED TO CARRY IN THE AREA THEREOF ADJACENT SAID MANDREL UNOBSTRUCTED CONDUIT-LIKE EXHAUST MEANS FOR THE REMOVAL OF GASEOUS FROM THE MOLD WHEN CLOSED.