Extruder

Claim 1

AN EXTRUDER FOR APPLYING A HELICAL EXTRUSION ON A PREFORMED CORE COMPRISING AN EXTERNAL CYLINDRICAL CASING HAVING INTERNAL CYLINDRICAL WALLS, AN END PIECE RIGID WITH AND CLOSING ONE END OF SAID CASING, AN EXTRUSION ORIFICE FORMED ECCENTRICALLY IN SAID END PIECE, BEARING MEANS MOUNTING SAID CASING FOR ROTATION ABOUT ITS LONGITUDINAL AXIS, A FIRST HOLLOW EXTRUSION SCREW MOUNTED COAXIALLY WITHIN SAID CASING AND HAVING AN EXTRUSION THREAD OF A MAJOR DIAMETER COMPLEMENTARY TO THE DIAMETER OF THE INTERNAL CYLINDRICAL WALLS OF SAID CASING AND HAVING INTERNAL CYLINDRICAL WALLS, SAID FIRST SCREW AND SAID CASING DEFINING AN EXTRUSION MATERIAL PASSAGEWAY THEREBETWEEN, A SECOND HOLLOW SCREW PROVIDING A SEALING FUNCTION FOR SAID PASSAGEWAY MOUNTED COAXIALLY WITHIN SAID FIRST EXTRUSION SCREW HAVING A THREAD OF A MAJOR DIAMETER COMPLEMENTARY TO THE DIAMETER INTERNAL CYLINDRICAL WALLS OF SAID FIRST EXTRUSION SCREW AND FORMED IN THE DIRECTION OPPOSITE TO THE DIRECTION OF SAID EXTRUSION THREAD OF SAID FIRST EXTRUSION SCREW, SAID SECOND SCREW RIGIDLY SECURED TO SAID EXTERNAL CASING FOR ROTATION THEREWITH, SAID HOLLOW SECOND SCREW PROVIDING A CORE PASSAGEWAY THROUGH SAID EXTRUDER, A CORE OPENING FORMED IN SAID END PIECE, MANDREL MEANS AT SAID END PIECE ONTO WHICH EXTRUDED MATERIAL IS DEPOSITED, AN ENTRY PORT FORMED IN SAID CASING AT THE END OPPOSITE FROM SAID END PIECE AND DRIVE MEANS ENGAGED WITH SAID CASING FOR ROTATING SAID CASING AND SAID SECOND SCREW TO DEPOSIT, AN ENTRY PORT FORMED IN SAID PREFORMED CORE MOVING THROUGH SAID EXTRUDER.