Patent ID: 7628945

Claim:
A method for forming radiused plastic articles from an extruded fluid plastic material, the method comprising the steps of: (a) Providing an extruding machine terminating in an extrusion die defining a path of travel for a fluid plastic material therethrough between an upstream end and a downstream end of the extrusion die, the extrusion die having an outlet opening extending longitudinally in the direction of the path of travel such that the extrusion die outlet opening is characterized by an upstream end and a downstream end, and the outlet opening further being oriented so that the fluid plastic material is extruded therefrom in a direction that is approximately perpendicular to the path of travel of the fluid plastic material through the extrusion die; (b) Providing at least a first pair of oppositely rotating rollers of tapered diameters disposed side by side to receive therebetween the fluid plastic material extruded from the extrusion die, the rollers arranged so that their longitudinal axes intersect and their smaller diameters are oriented towards the downstream end of the extrusion die; (c) Extruding a fluid plastic material through the extrusion die outlet opening, the extrudate being characterized by a higher flow rate proximate the upstream end of the extrusion die outlet opening and a lower flow rate proximate the downstream end of the extrusion die outlet opening to thus form a radiused extrusion; (d) Drawing the extrudate from the extrusion die outlet opening with the tapered rollers without significantly altering the radiused shape of the fluid plastic material received therebetween; (e) Cooling the extrudate; and (f) Sequentially cutting said cooled extrudate to form therefrom a plurality of radiused plastic articles.