CONTROL APPARATUS FOR HYDRAULIC SERVO UNITS

摘要

In a hydraulic servo unit comprising a cylinder and a piston slidably inserted therein, the cylinder chamber being divided by a piston portion into a rod-side cylinder chamber and a head-side cylinder chamber a control apparatus for the hydraulic servo unit comprises a first hydraulic line connecting the rod-side cylinder chamber with the hydraulic pressure source which supplies working fluid of predetermined pressure, a second hydraulic line connecting the head-side cylinder chamber with the first hydraulic line through a first solenoid valve of duty-ratio-control, a drain hydraulic line connecting the head-side cylinder chamber with drain through a second solenoid valve of duty-ratio-control.