Apparatus for removing volatile constituents contained in liquid synthetic plastic melts

Claim 1

AN APPARTUS FOR REMOVING VOLATILE COMPONENTS FROM LIQUID PLASTIC MELTS BY VACUUM TREATMENT, WHICH COMPRISES: (A) AN EVACUATION CHAMBER HAVING AN INLET FOR THE INTRODUCTION OF LIQUID PLASTIC MELT, AN OUTLET FOR THE REMOVAL OF DEVOLATIZED PLASTIC PRODUCT, AND AN EVACUATION APERTURE, SAID EVCUATION APERTURE BEING DEFINED BY THE ADJACENT PERIPHERAL EDGES OF A CUT-OFF PORTION OF SAID EVACUTION CHAMBER, AID EVACUATION CHAMBER BEING SUBSTANTIALLY CYLINDRICAL AND VERTICALLY DISPOSED, AND AT LEAST ONE OF THE EDGES OF SAID EVACUATION APERTURE BEING SHARPLY BEVELED TO PREVENT THE ADHESION OF PLASTIC MELT THERETO TO THE FLOW OF SAID MELT BEING DOWNWARD, AND ONE EDGE OF SAID EVACUATION APERTURE BEING A LOWER EDGE WHICH IS FLARED OUTWARD TO CAPTURE SAID DOWNWARD FLOWING MELT; (B) A ROTATABLE WORM FOR TRANSFERING THE PLASTIC MELT DOWNWARDLY FROM THE INLET OF THE EVACUATION CHAMBER, PAST THE EVACUATION APERTURE THEREOF, AND TO THE OUTLET OF SAID CHAMBER, SAID WORM BEING DISPOSED WITHIN SAID CHAMBER AND HAVING EDGES WHICH ARE IN WIPING CONTACT WITH THE WALLS THEREOF; (C) AN EVACUABLE ENCLOSURE SURROUNDING THE EVACUATION APERTURE IN SAID EVACUATION CHAMBER AND IN COMMUNICATION THEREWITH, SAID ENCLOSURE HAVING MEANS FOR CONNECTION TO A VACUUM SOURCE FOR THE REMOVAL OF SAID VOLATILE COMPONENTS; (D) MEANS FOR ROTATING SAID WORN WHEREBY WHEN SAID ENCLOSURE AND EVACUATION CHAMBER ARE EVACUATED, AND THE PLASTIC MELT IS TRANSFERRED DOWNWARD WITHIN SAID CHAMBER FROM THE INLET THEREOF, PAST THE EVACUATION APERTURE AND TO THE OUTLET, THE VOLATILE PRODUCTS IN SAID MELT ARE REMOVED AND A DEVOLATIZED PLASTIC PRODUCT IS DISCHARGED AT THE OUTLET OF SAID CHAMBER.