Home >> Patent Categories

Patents

Patent Search

United States Patent 5628560
Douris , ê et al.

Double-screw extruder

Eigruber May 13, 1997

Abstract

A screw for a double-screw extruder has its flight defining an outer cone and an inner cone of different convergencies with the inner cone converging more steeply than the outer cone from the feed end to the exit end of the extruder. Where A is the outer diameter at the feed end, B is the outer diameter at the exit end, C is the flight height at the feed end and D is the flight height at the exit end, the screw is defined by the relationship m.times.(A-B)/B=(C-D)/D where m is less than zero and greater than -0.75, the screw having a length L.gtoreq.15B.