Patent ID: 8550800
Filing Date: 2013-10-08
Classification: B29C

Abstract:
1. An injection molding machine for two-material molding comprising: a first die plate attached with a first die; a second die plate attached with a second die and opposed to the first die plate; a reversal pedestal provided between the second die plate and the first die plate; a rotary die plate provided on the reversal pedestal to be rotatable 180 degrees, on both surfaces of the rotary die plate being respectively attached with rotary dies alternately opposed to the second die and the first die; first die opening and closing means for enabling the first die plate and the second die plate to relatively open and close in a direction in which the first die plate and the second die plate approach and separate from each other; second die opening and closing means for enabling the first die plate and the rotary die plate to relatively open and close in the same direction as the direction of the second die plate; die tightening means for tightening the first die plate, the second die plate, and the rotary die plate; a first injecting unit that plasticizes a resin material and injects and fills the resin material in a first cavity formed between the first die and the rotary die opposed to the first die; a second injecting unit that plasticizes a resin material and injects and fills the resin material in a second cavity formed between the second die and the rotary die opposed to the second die; a heating device that heats at least one of the first die, the second die, and the rotary dies; a cooling device that cools at least one of the first die, the second die, and the rotary dies; and a control unit that controls the heating device and the cooling device, wherein after completion of injection molding in the first injecting unit or the second injecting unit, prior to rotating the reversal pedestal 180 degrees in order to inject and fill the resin material in the first injecting unit or the second injecting unit, the control unit issues a heating start command to the heating device, starts heating of the first cavity and/or the second cavity, maintains, before completion of the rotation of the reversal pedestal, temperatures of the dies within a temperature range higher than a die temperature during heating start and lower than the die temperature during injection, and, after the completion of the rotation of the reversal pedestal, resumes the heating of the first cavity and/or the second cavity.