INJECTION MOLDING DEVICE

PROBLEM TO BE SOLVED: To successfully finish the external appearance of a synthetic resin-molded article by preventing orientation lines formed behind an opening-forming body facing a gate with respect to the resin-injecting direction, from being observable from the outside of the molded article to the utmost, even in the synthetic resin-molded article containing filler and having an opening such as a hole.SOLUTION: After melted thermoplastic synthetic resin 30 containing the filler 29 is injected from a first gate 26A and the orientation lines 27A2, 27B2 are formed, simultaneously with stopping of the injection of the synthetic resin from the first gate 26A, the injection of the synthetic resin is started from second gates 26B, 26B before stopping or after stopping. After lifting pins 28A, 28B having upper end surfaces having been flush with a cavity forming surface of a movable metal mold are uplifted in a cavity 14 when the injection of the synthetic resin is started from the first gate 26A, the lifting pins are lowered so as to be returned to original positions.