| 摘要 |
PURPOSE:To prevent delay of function by functioning a pressure control valve with correspondence to the clearance of steering wheel and feeding pressurized oil to one of left/right sides of a compensation chambers formed at the opposite sides of slide sleeve thereby correcting the clearance. CONSTITUTION:Upon occurrence of large clearance on a steering wheel, a control unit 24 will perform operation on the basis of output signals from a steering sensor 25 and pressure sensor 28 to drive a motor 88 on the basis of operation results thus to slide a spool 87 of a compensation pressure control valve 23. Pressurized oil in the upstream of a restrictor 19 is fed to any one of compensation pressure chambers 17, 18 to slide a slide sleeve 42 to the left or right. Consequently, pressure port 45 and pressure intermediate communication port 65 will communicate with any one of the cylinder ports 46, 47 to feed pressurized oil into any one of left/right chambers 78, 77 of power cylinder thus to extend or contract the cylinder 14 and to correct the clearance. |
