| 摘要 |
PURPOSE:To obtain a highly kneading screw exceedingly improved in kneading properties and reduced in resin temperature difference in the stroke direction by providing a mixing part composed of a melting and a shearing section with special shape at the end of the screw. CONSTITUTION:The mixing part (b) and the flow-back preventive mechanism (c) are provided at the end of the metering part (a) of the screw 1. The mixing part (b) is made up of a polyhedron of which the section is polygonal, the flow-back preventive mechanism c is composed of the seat 4, the check ring 5, the retainer seat 6 and the ring 7. The inner wall surface 13 of a cylinder and the notched slopes 14, 15 of the polyhedron 2 make up voids having curved line of small curvature. The notch slope 14 makes up the melting section 16 and the notch slope 15 due to the curved line of large curvature makes up the shearing section 17. The melting section 16 is connected in a constant depth with metering part and the flow-back preventive mechanism (b) while the shearing section 17 is opened for the side of the metering part (a) but closed by the weir 18 for the side of the flow-back preventive part. |
