Apparatus for simultaneously advancing and working plastic material

Claim 1

APPARATUS FOR SIMULTANEOUSLY WORKING ADVANCING AND EXTRUDING ORGANIC PLASTIC COMPOUNDS, WHICH COMPRISES AN ELONGATED EXTRUDING CYLINDER PROVIDED WITH AN IMPERFORATE CYLINDRICAL BORE EXTENDING LONGITUDINALLY THERETHROUGH AND HAVING A COMPOUND WORKING ZONE INTERMEDIATE ITS ENDS, A SINGLE STOCK SCREW HAVING A HELICAL THREAD THEREON MOUNTED CONCENTRICALLY WITHIN THE BORE FOR ROTATION ABOUT THE LONGITUDINAL AXIS OF THE BORE, AND A SERIES OF UNRIBBED TUBULAR LINERS MOUNTED IN END TO END RELATIONSHIP IN THE COMPOUND WORKING PORTION OF THE BORE TO FORM A CONTINUOUS PASSAGE THERETHROUGH, AT LEAST ONE OF SAID LINERS HAVING AN INTERIOR BORE EXTENDING ECCENTRICALLY WITH RESPECT TO THE STOCK SCREW TO PROVIDE CLEARANCE BETWEEN SAID LINER BORE AND THE HELICAL THREAD ALONG A SUBSTANTIAL LENGTHWISE PORTION OF THE COMPOUND WORKING PASSAGE, AND THE OTHER LINERS HAVING INTERIOR BORES EXTENDING CONCENTRICALLY WITH RESPECT TO THE STOCK SCREW TO PROVIDE SUBSTANTIALLY NO CLEARANCE BETWEEN THEM AND THE HELICAL THREAD, WHEREBY A PLASTIC COMPOUND ADVANCING THROUGH THE COMPOUND WORKING ZONE IS SUBJECTED TO TURBULENT MIXING AND SHEARING ACTION TO BRING IT TO A HIGH DEGREE OF EXTRUDABILITY.