PRESSURE ADJUSTING DEVICE IN TWIN-SCREW EXTRUDER

摘要

PURPOSE:To correspond to the melt extrusion of all of a resin raw material only by changing the outer diameters of flights by providing disc-shaped flights to the center shafts in the spaces of respective screws and providing an adjusting pin inserted in the gap between both center shafts through the gap between both flights to adjust the passage area of the resin material to a barrel. CONSTITUTION:Each of screws 2 is constituted by providing a screw part 5 and a kneading disc part to a center shaft 2a and the spaces 3 only of the center shafts 2a having no screw part 5 are provided to both screws 2 at the same positions in the axial direction of them. Flight members 6 are respectively provided to the center shafts 2a in the spaces 3 of the screws 2 and opposed mutually at a predetermined interval in the axial direction. A pair of adjusting pins 4 inserted in the gap between both shaft parts 6a through the gap between both flights 6b are arranged to a barrel 1. As mentioned above, a pressure adjusting device is constituted of two flight members 6 and two adjusting pins 4 and a resin passage can be almost perfectly closed.