Csongor; D. G. U.S. Pat. 4,749,279 (1988)

In a copending application Ser. No. 298,065 filed Aug. 31, 1981 modular mixing apparatus has been disclosed combined with a barrel and main power driven extruder screw and the mixing apparatus is necessarily required to be at the same speed as the main power driven extruder screw and operates through a common barrel member. In the present invention improved modular mixing apparatus has been constructed and arranged to operate with independent drive means for rotation in a separate stationary sleeve member and extruded material leaving the main extruder screw and barrel is introduced into the mixing module. The mixing apparatus may, in this form, be driven at variable speeds which are independent of the speed of the main extruder screw. The improved modular mixing apparatus of this invention also includes a newly devised shearing lug module. The shearing lug module produces greatly attenuated subdivision of material obtained by the use of shearing lugs operating in combination with annular shearing channels formed in the stationary sleeve member. The shearing lug module combined with a basic component assembly of the invention may find application, in dealing with some materials, as a single processing module only especially when driven at suitably increased speeds of rotation. It should also be understood that the shearing lug module may be driven by a conventional extruder screw in some desired instances.

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