Patent ID: 6997596
Filing Date: 2006-02-14
Classification: B29C

Abstract:
1. A plastics extruder screw tip comprising: (a) an inwardly and forwardly tapered melt converging surface; and, (b) at least a first dasher, the dasher having a proximal and a distal end, the proximal end being fixedly attached to or formed wholly with the inwardly and forwardly tapered melt converging surface; the inwardly and forwardly tapered melt converging surface forming a shape selected from the group consisting of conic shapes, conical shapes, spheric shapes, spheroidal shapes, and ellipsoidal shapes; the inwardly and forwardly tapered melt converging surface having an axis of rotation, the distal end of the at least first dasher comprising a curved surface having radii of curvature extending toward the axis of rotation; the proximal and distal ends of the at least first dasher extending helically about the axis of rotation; the curved surface of the distal end of the at least first dasher having a rearward end and a forward end, the curved surface's radii of curvature progressively lengthening; and further comprising a second dasher, the at least first dasher and the second dasher being arranged opposingly about the axis of rotation; the inwardly and forwardly tapered melt converging surface having a rearward end, and further comprising screw root attaching means comprising a helically threaded circular cylinder fixedly attached to or formed wholly with said rearward end; the helically threaded circular cylinder comprising an interior oil return conduit.