| 摘要 |
PROBLEM TO BE SOLVED: To effectively regenerate energy possessed by a return fluid discharged from a hydraulic pressure actuator even in an open circuit. SOLUTION: A hydraulic pressure actuator control circuit 25 is arranged for controlling a working fluid supplied to a boom cylinder 8bmc, a stick cylinder 8stc and a bucket cylinder 8bkc from main pumps 17A and 17B of a hybrid type driving device 10. This hydraulic pressure actuator control circuit 25 has a boom assist pump 84as for assisting a flow rate of the working fluid supplied to the boom cylinder 8bmc from the main pumps 17A and 17B of the hybrid type driving device 10, an energy regenerative motor 26 arranged in a return fluid passage 55 for passing a return fluid discharged from the boom cylinder 8bmc, and a motor-driven generator 87 for a boom driven by the energy regenerative motor 26. This motor-driven generator 87 for the boom drives the boom assist pump 84as via a clutch 88. COPYRIGHT: (C)2007,JPO&INPIT |
