PURPOSE: To finely control injection by giving a flow rate control valve opening command earlier by the quantity corresponding to delay of time or injection stroke caused by inertia, etc., of working oil and controlling in the case of changing over the flow rate control valve from low speed shifting to high speed shifting.
CONSTITUTION: At the time of executing the speed control in a cylinder 1, liquid supplying rate and liquid discharging rate into the cylinder 1 are regulated. The delay quantity of the time or the injection stroke based on the inertia, compressibility, etc., of the working oil from output of the high speed shifting command during the low speed shifting until the high speed rise starts is obtd. as a function in inverse proportion to the speed or the flow rate at the low speed. At the time of controlling the flow rate earlier by the quantity corresponding to the delay quantity obtd. with a speed computing element 30 and the other computing elements 32, 34, etc., the valve opening command and high speed injection speed as the valve opening condition or the valve opening degree and the high speed rise time corresponding to this are transmitted from a control command transmitter 37 to pulse motor 20 in the flow rate control valve 2 to control the flow rate control valve 2. By this method, the desired high speed rise starting is executed and the good quality injection product is easily obtd. with the fine injection control.
UENO TOYOAKI
HIGUCHI TADAAKI
| JPS60234760A | 1985-11-21 |
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