Screw-type extruding machine having a screw element defining a groove with an expansion region at each end thereof

Abstract

A screw-type extruding machine includes a housing; a driveable shaft disposed inside the housing and including a rotational moment transfer element; and at least one screw element. The screw element has two ends and defines a longitudinal groove therein for receiving the rotational moment transfer element of the shaft, the shaft thereby transferring its rotational moment to the screw element. The groove is configured such that it defines two expansion regions, each expansion region having an axial extent, the groove having side surfaces which diverge with respect to a longitudinal axis of the groove along the axial extent of each expansion region in a direction toward a corresponding one of the two ends of the screw elements, a width of the groove thereby increasing in a direction toward its two ends along each expansion region.

Dependencies are inferred from the claim text.