| 摘要 |
<p>PROBLEM TO BE SOLVED: To regulate setting pressure of a pair of relief valves setting the working pressure of a hydraulic motor reversibly operating an inertia body simply and appropriately corresponding to acceleration and deceleration of the inertia body. SOLUTION: This hydraulic drive device is constituted so that pressure oil from a pump 10 is fed to a hydraulic motor 16 through a changeover valve 12 and a feed/discharge line 14a, the return oil is discharged to a tank 20 through a charge/discharge line 14b and a low pressure line 18, hence a turning body 22 is operated normally and reversely, and working pressure at acceleration and deceleration at this operation are set through relief valves 24a, 24b provided on the respective ports of the hydraulic motor 16. In this case, a variable restriction valve 44 of which the opening is regulated by an external signal 42 is provided on the discharge port side 38 of the relief valves, and the discharged oil from the relief valves 24a, 24b is discharged to the low pressure line 18.</p> |
