| 摘要 |
PURPOSE:To enable continuous extrusion molding without closing a vent hole, by providing a specific cylinder mechanism for pushing in a molten material, when said material is about to flow out, to the vent hole for sucking and removing a volatile component from the molten material. CONSTITUTION:A cylindrical body 6 having a vent hole 7 is provided to the cylinder 2C of a degassing part C and a push-in member 9 protruding up to the vicinity of the screw C is further provided in the cylindrical body 6 in a freely reciprocating manner so as to close the vent hole 7. If a molten material is flooded into the cylindrical body 6, by falling the push-in member 9, the molten material can be pushed back into the cylinder 2C to be prevented from stagnating in the cylindrical body 6. The surface of the molten material is always renewed to enable the promotion of degassing and, because the vent hole 7 is opened after the molten material was pushed back by the reciprocating movement of the push-in member 9, venting action is subjected to no trouble. |
