| 摘要 |
PURPOSE:To prevent the generation of a large amount of burrs and voids due to resin properties and die shape by a method wherein the pressing speed and dwell pressure of resin are each controlled in steps. CONSTITUTION:When a plunger reaches a position A of abutment with the synthetic resin, it comes to the first speed and starts pressing. Next, when the plunger reaches a fixed position B, it comes to the second speed. Then, the plunger is detected in pressure and comes into the step of dwell pressure at a point C. After coming into dwell pressure, it switches to the second pressure (point D) by using the signal of the time measured by a timer. Finally, the pressure is extracted at a point E after a time initially set by the timer, and the plunger 7 starts ascending (point F), resulting in molding finish. Since the pressing speed and dwell pressure can be controlled in steps by considering resin properties or die cavity shape, the state of cast filling of resin improves, and the generation of voids and burrs is inhibited to the minimum; accordingly, products of good quality can be obtained. |
