| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hydraulic drive system capable of reducing loss in consumption power in a charge pump and also capable of preventing an increase in cost. <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 actuator 14. A charge circuit 16 replenishes the hydraulic fluid passage 15 with a hydraulic fluid when a hydraulic pressure in the hydraulic fluid passage 15 is lower than a hydraulic pressure in a charge passage 35. When the hydraulic actuator 14 is not working, charge hydraulic pressure reducing parts 24d and 37 reduce the hydraulic pressure in the charge passage 35 to be lower than the hydraulic pressure in the charge passage 35 when the hydraulic actuator 14 is working. <P>COPYRIGHT: (C)2013,JPO&INPIT |
