Patent ID: 6382826
Filing Date: 2002-05-07
Classification: B29C

Abstract:
A compact extruder with multiple parallel screws having a variable pitch arrangement, comprising:an outer casing which includes at least two chambers that contain at least two screws which allow material to flow from one chamber to the other chamber through a passage, and that have a feed inlet for the material to be treated and an outlet for the material; wherein each chamber includes at least one pair of housings for the corresponding at least one pair of screws which engage with one another, each screw having a long-pitch portion and a short-pitch portion; and wherein at least one of the screws in each set of screws is attached at one end to a pair of differentials which, via cogwheels that are fitted to shafts of the screws and exit from the differentials, continuously vary speed of the screws.