| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the number of parts, to reduce manufacturing cost, and to facilitate/stabilize the circuit control by nullifying or simplifying a braking circuit. To drastically enhance the quality of a product by performing the braking control firmly and precisely. SOLUTION: A four port servo valve 4 for driving/controlling an injection cylinder 2 is prepared. A port A and a port B of this servo valve 4 are connected to a front oil chamber 2f and a rear oil chamber 2r of the injection cylinder 2, respectively, while a port P of the servo valve 4 is connected to a hydraulic driving source 5. A port T of the servo valve 4 is connected to an oil tank 3 via an opening/closing valve 6 for switching to an ordinary mode or a differential mode, while the port T is connected to the rear oil chamber 2r of the injection cylinder 2 via a logic valve 7.</p> |
