Patent ID: 6682213
Filing Date: 2004-01-27
Classification: B29B,B29C,B29K

Abstract:
A twin-screw continuous kneading apparatus comprising:a barrel having a pair of kneading chambers formed therein in communication with each other; a pair of kneading screws rotatably inserted in said kneading chambers; first supply means for supplying a material to be kneaded into said kneading chambers, said first supply means being connected to an upstream end portion of said barrel; second supply means for supplying an additive into said kneading chambers, said second supply means being connected to the upstream end portion or a midstream portion of said barrel; an additive feed zone provided by a part of each of said kneading screws corresponding to said second supply means, said additive feed zone being made up of screw segments; a downstream feed zone provided by a part of each of said kneading screws downstream of said additive feed zone, said downstream feed zone being made up of screw segments; and an additive mixing zone provided by a part of each of said kneading screws downstream of said additive feed zone and between said additive feed zone and said downstream feed zone, said additive mixing zone being made up of rotor segments arranged successively in an axial direction of said kneading screw, wherein a segment group constituting said additive mixing zone satisfies conditions (a) and (b) given below: (a) the segment group comprises only feed segments having flights twisted in a direction to feed the kneaded material downstream with rotation of said kneading screw, or comprises said feed segments and neutral segments having flights parallel to the axial direction of said kneading screw, and (b) each of said rotor segments making up the segment group has flights formed by arranging a high-height tip portion providing a comparatively small tip clearance relative to an inner wall surface of said kneading chamber and a low-height tip portion providing a comparatively large tip clearance alternately in the axial direction in succession.