Method for molding resin product

Abstract

Abstract PURPOSE:To shorten the cycle time required for molding and at the same time facilitate the control of temperature, metering and the like of resin material by a method wherein molten resin is injected under low pressure in a cavity in the middle of a course to advance a movable mold to a fixed mold for mold clamping and further the advancement of the movable mold is continued at low speed to the mold clamping completion position. CONSTITUTION:Mold clamping is started by advancing a movable mold 4 to a fixed mold 2 at high speed or at medium speed. After that, when the ingress of the movable mold 4 into the fixed mold 2 by the predetermined amount such as to the position about 5-10mm ahead the mold clamping completion position is detected with a limit switch 15, the forward speed of the movable mold 4 is changed-over to low speed. After that, a cavity 6 is evacuated and at the same time molten resin 7 is injected by the amount of material necessary for product from an injection unit 5 in the cavity 6 under low pressure (15-40kg/cm<2>). In succession, the mold clamping is continued at low speed. As a result, the molten resin 7 injected in the cavity 6 is compression- molded so as to copy the shape of the cavity. Next, when the molten resin 7 in the cavity 6 cools down and cures, the movable mold 4 is retreated and the resin in the form of a product is cleared out of the mold by being ejected with an ejector pin 13.

Inventors

• 👤 Setsuji Yamamoto
• 👤 山本　節二
• 👤 Tsuneo Kurihara
• 👤 栗原　恒夫

Bibliographic Details