Patent ID: 6187241
Filing Date: 2001-02-13
Classification: B29C

Abstract:
A method of co-extruding multiple plastic material outer and interior flowing streams as for injecting through a gate region into a mold cavity to produce a molded product, that comprises, flowing the plastic materials from stream sources along a longitudinally extending hollow extruder; receiving the outer and interior streams from the extruder and combining the streams of such flowing plastic materials with at least one inner stream that is to serve as an interior core of a resulting molded plastic product within outer and interior streams of plastic material to serve as covering plastic material layers; restricting the combined streams within and along the longitudinally extending tubular extruder to force the combined streams to flow along concentric annular flow paths within and along the longitudinally extending extruder to the cavity gate region, with the annular core stream encased by interior and outer annular covering plastic material stream layers; and, at the gate region, splitting the concentric annular streams along opposite transverse directions to inject into corresponding opposite transverse sections of the cavity.