| 摘要 |
<p>A hydraulic cylinder (9) actuates a control valve (8) to control pressure of control pressure pipes (22,23). A control valve (6) is arranged between control pressure pipes (20,21) and is actuated by a hydraulic motor (7) to control pressure of control pressure pipes (20,21) based on control pressure of control pressure pipes (22,23). A pressure limiting device (35) is arranged in branch line (26) connected with control pressure lines (20,21), for maintaining control pressure of control pressure lines (20,21) by valve device (27).</p> |
