| 摘要 |
PURPOSE:To mold a high quality product, by providing a pressure change speed variable means capable of continuously changing injection pressure at a desired speed while providing a setting means for setting a pressure change speed and a pressure change period to plural stages and the control means for controlling the pressure change speed variable means. CONSTITUTION:When a screw 16 reaches a set position after a resin material was injected in a mold 22 and a pressure chamber 36 reaches pressure P1 after a period T1 was elapsed, the pressure control of a solenoid pressure control valve 38 is started on the basis of the signal of a process controlling CPU 48 and the pressure of the pressure chamber 36 is fallen at a constant falling speed so as to reach the objective pressure P2 set by an objective pressure setting device 54 after the pressure holding period T2 set by a holding period setting device 52. After the period T2 was elapsed, the pressure falling speed is altered so that the pressure in the pressure chamber 36 reaches second objective pressure P3 after the second holding period T3 set by the setting device 52 was elapsed and the pressure in the pressure chamber 36 is controlled. Because there is no abrupt change in injection pressure, a good quality product can be stably molded. |
