| 摘要 |
PURPOSE:To intend the shortening of a molding cycle at an injection molding, by shutting a runner after filling a cavity part to which a specified well part is linked with a molten resin via the runner. CONSTITUTION:An ejector pin 14 for ejecting a molded article molded in a cavity 11 is energized by a spring 15 at its back end side and when a molten resin is forced in, the pin 14 descends so as a well part 16 is formed on its upper part. When the molten resin is forced into the cavity 11 shaped between the cavity plates 3, 5 via a runner 12 and a gate 13, the pin 14 descends against the energizing force of the spring 15 and the resin is filled in the shaped well part 16 too. After a lifting plate 9 is raised and the flow passage of the runner 12 is shut by a slide pin 17, the mold 1 is cooled, then the molten resin solidifies shrinking and at that time the pin 14 is raised by the restoring force of the spring 15 and the shrinkage by solidification of the molded article is compensated by the supply of the resin from the well part 16. |
