Csongor; D. G. U.S. Pat. 3,836,127 (1974)

An improved apparatus for extruding plastic materials provides for processing a mixture of plastic particles, additives, dyes, and the like by means of an extruder screw to form a melted mass which is moved in a helically-directed stream in a confined space. At a predetermined point, flow-diverting means in said confined space abruptly changes the flow pattern. Portions of the helically-melted mixture advanced by the extruder screw and coming into contact with the flow-diverting means, undergo a continuous shearing action and sheared-away portions of the melted material are constantly turned over upon themselves and forced through restricted passageways of short axial length in a highly turbulent flow pattern. After leaving the restricted passageways, the melted material again moves in a helical path of flow. Turbulency thus induced at one or more points in the flow line brings together melted and unmelted particles more effectively and rapidly, and there is further accomplished an improved mixing together of the melted mixture and the additives and other components.

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