| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hydraulic drive system capable of preventing insufficient supply of a hydraulic fluid to a hydraulic pump and also capable of preventing enlargement of a charge pump. <P>SOLUTION: In the hydraulic drive system 1, a hydraulic fluid passage 15 constitutes a closed circuit between a main pump 10 and a hydraulic cylinder 14. The charge pump 28 replenishes the hydraulic fluid passage 15 with the hydraulic fluid. A pump control unit 24a performs flow rate reduction control. Under the flow rate reduction control, the pump control unit 24a reduces an inlet flow rate so that an inlet flow rate of the main pump 10 is not larger than the maximum discharge flow rate of the charge pump 28 when a stroke position comes closer to the stroke end of a cylinder rod 14a than a predetermined reference position. <P>COPYRIGHT: (C)2013,JPO&INPIT |
