| 摘要 |
PURPOSE:To make the increasing time of casting force uniform and to control flow rate to a prescribed time irrespectively of the injection speed just prior to completion of filling a molten material into a cavity by providing separately an opening degree for filling and pressurizing to a flow rate control valve and controlling the flow rate. CONSTITUTION:A magnetic detector 27 detects the scale of a magnetic scale 21 and forms the same as an impulsive signal. A stroke detector 28 counts the signal and provides the stroke position St of a plunger 4. A speed detector 29 converts the stroke position St to the speed signal (v) of the plunger 4 and an acceleration detector 30 converts the speed signal to an acceleration signal alpha. A judger 31 receives the signal alpha when the signal (v) attains a specified speed threshold v0 and judges whether said signal attains a negative value or not. A stroke setter 25 outputs a coincidence signal when the stroke signal from the detector 28 coincides with the set stroke position. An opening degree controller 24 regulates a flow rate control valve 33 by means of a pulse motor 32 until the valve opening degree set in an opening degree setter 26 upon receiving of said signal. |
