| 摘要 |
PURPOSE:To increase both a yield and working efficiency by controlling a servo valve by detecting an internal pressure of a molten metal using a load on a pushing pin, filling a cavity with the molten metal surely, and preventing formation of flashes in a stage in which a molten metal plunger moves forward at a final low speed in a diecasting process. CONSTITUTION:A molten metal A is poured 20 into an injection sleeve 12, a piston 13C of a small diameter and a plunger 13 are moved forward at a low speed by a servo valve 22, and the molten metal A is injected into the cavity rapidly by a booster piston 19 of a large diameter actuated by a molten metal A. The plunger 13 is moved again and forward at a low speed when a control circuit 17 is actuated by a signal from a limiter 26 touched by a nodal part 131. The plunger 13 is stopped by the control circuit 17 transmitted a load signal from a load converter 16 set on a product pushing-out pin 10 when the internal pressure of the molten metal A reaches the specified pressure value. In this way, the cavity 9 is filled with the molten metal A surely and the formation of flashes is prevented by the appropriate internal pressure of the molten metal A, so that a yield and working efficiency are increased. |
