| 摘要 |
PURPOSE:To secure the retention of mold closing by a method wherein the mold clamping force applied to a mold after injection molding is properly hed by the elastic force of spring members, which are installed between a mold clamping plate and a mold mounting plate, until a shutter plate, which receives the reactions of the spring members by restricting a pressure receiving rod, is removed from the tip end of the pressure receiving rod. CONSTITUTION:Every mold clamping unit 31 is rotated by 90 deg. together with a rotary table 28. At each mold clamping position, molds 51 are clamped together by pressing a mold clamping plate 35 through a mold opening and closing rod 39 with the ram 23a of a mold clamping cylinder 23. When an injection cylinder 52 is retreated so as to part from the mold 51 after the completion of injection, the ram 23a is raised to its initial position for rotation, resulting in removing the pressing force of the ram 23a. However, the mold clamping force of the mold 51 is properly retained by means of the elastic force of the spring members 36. Said elastic force is maintained until the mold clamping unit 31 reaches a mold opening and closing position and relieved when a shutter plate 41, which receives the reactions of the spring members 36 by restricting a pressure receiving rod 40, is removed from the tip end of the pressure receiving rod by means of a releasing cylinder 49 at the mold opening and closing position and consequently the pressure receiving rod 40 is set free. Accordingly, the time up to mold opening can be properly held by means of the pressures of the springs. |
