Screw extruder for processing rubber or plastics material

Abstract

A screw extruder for processing rubber or plastics material, comprising a cylinder jacket with a feed hopper, a central geared shaft and geared planet shafts disposed between the central shaft and the cylinder jacket and drivably engaged with the central shaft and the cylinder jacket, wherein parts of at least some of the planet shafts are bare of gearing. Advantageously each alternate planet shaft is only partly geared, the gearing extending for only approximately half the length of the shaft, at one end or the other end or in two quarter length portions at the opposite ends. Alternatively each third planet shaft is only partly geared. Preferably each geared part of a planet shaft which is only partly geared overlaps with a geared part of the planet shaft which follows it in the direction of rotation.

Dependencies are inferred from the claim text.