| 摘要 |
PROBLEM TO BE SOLVED: To consuming energy accumulated in an accumulator only by a quantity related to steering assist force so as to reduce a pump operating time and so as to reduce an energy loss by operating a variable means of a hydraulic motor by means of a movable member and operating a switching valve at the same time. SOLUTION: A check valve 8 and an accumulator 13 are arranged in the middle of a working fluid pressure passage 11 through which working fluid discharged from a hydraulic pump 9 is introduced to a hydraulic motor 2. A selector valve 14 controlling connection and disconnection between an intake port 5 of the hydraulic motor 2 and the working fluid pressure passage 11 is arranged in the working fluid pressure passage 11 on the downstream side beyond the accumulator 13. A movable member 41 moving in the axial direction because of relative rotation between an input shaft 1 and an output shaft 4 is arranged, and by means of the movable member 41, a cam ring 17 serving as a variable means of the hydraulic motor 2 and the selector valve 14 are operated. In this way, energy accumulated in the accumulator 13 is consumed only by a quantity related to steering assist force, so that an energy loss can be reduced. |
