METHOD OF MANUFACTURING EXPANDABLE PLASTIC MOLDING, EXPANDABLE PLASTIC MOLDING, AND INJECTION MOLDING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing an expandable plastic molding using a resin raw material to which a foaming agent is added, the expandable plastic molding, and an injection molding machine used for the manufacturing method.;SOLUTION: The following processes are performed: a metering standby step in which the resin raw material to which a chemical foaming agent is added is supplied from a raw material supply part 21 of the injection molding machine 1 to the inside of a cylinder 2, the resin raw material pushes open a central part check valve 5 and a tip check valve 6 provided on a screw 3 ahead while melting to move to the tip side of the cylinder 2, a rotary action of the screw 3 finishes after a predetermined amount of the resin raw material melted and kneaded is filled between the tip check valve 6 and a nozzle 22 of the cylinder 2, and further, the resin raw material is pooled between the nozzle 22 and the tip check valve 6 while the tip check valve 6 and the central part check valve 5 are kept in a closed state; and following to the metering standby step, an injection step of injecting the resin raw material pooled between the tip check valve 6 and the nozzle 22 to a cavity 14 of a mold 10A.;COPYRIGHT: (C)2012,JPO&INPIT