| 摘要 |
PROBLEM TO BE SOLVED: To provide a pump device capable of controlling a flow rate while reducing driving torque of a pump.SOLUTION: A pump device 100 includes a pump 1, a flow control valve 2 having a spool 21 operated in accordance with a differential pressure acting to both ends and circulating a part of working fluid delivered from the pump 1 to an intake side, and a differential pressure adjusting device 3 for adjusting a differential pressure Pd acting to both ends of the spool 21 to be a target differential pressure Pt. The differential pressure adjusting device 3 includes a pressure adjusting chamber 34 facing one end of a spool 31 and communicated with a second fluid pressure chamber 24, and a pilot chamber 35 facing the other end of the spool 31 and to which a pressure in a delivery flow passage 82 is guided, and a pressure P4 in the pressure adjusting chamber 34 is adjusted so that a differential pressure Pe between the pressure P4 in the pressure adjusting chamber 34 and a pressure P3 in the pilot chamber 35 becomes the target differential pressure Pt.SELECTED DRAWING: Figure 1 |
