Patent ID: 6254266
Filing Date: 2001-07-03
Classification: B29B,B29C

Abstract:
A polymer melt mixer for an extruder assembly having a barrel including a cylindrical bore defining a cylindrical chamber in which a driven extruder screw is positioned for rotation about its axis to move polymer melt in a downstream direction through said chamber, said mixer comprising:a driven shaft adapted to be attached to a downstream end of and driven in rotation by the extruder screw;a least one driven rotor ring coaxial with said driven shaft and mounted on said driven shaft for rotation therewith about a longitudinal axis of said driven shaft, said one driven rotor ring having a pair of axially spaced, radially extending faces;a least one floating ring coaxial with said driven shaft and mounted on said driven shaft for rotation relative thereto, said one floating ring having a pair of axially spaced, radially extending faces, said one floating ring being positioned adjacent to said one driven rotor ring with adjacent ones of said faces being spaced apart; andsaid one driven rotor ring and said one floating ring each having a plurality of polymer flow passageways extending therethrough between said axially spaced faces whereby when said driven shaft is attached to a downstream end of the extruder screw in the cylindrical chamber and the extruder screw is driven in rotation causing polymer melt to flow through said flow passageways, said driven shaft and said one driven rotor ring are drivingly rotated by the extruder screw and said one floating ring is free to rotate at a speed less than a speed of rotation of said one driven rotor ring while said polymer melt is being further mixed due to different speeds of rotation between said one driven rotor ring and said one floating ring.