| 摘要 |
PROBLEM TO BE SOLVED: To realize energy saving by making difference in absorption torque (pump flow rate) of a hydraulic pump between a shrinkage side and an elongation side of the hydraulic cylinder to reduce loss. SOLUTION: In a return piping 17 through which return oil from an actuator to a tank passes, pressure becomes higher as return flow rate increases, and a condition of operation in the elongation side and the shrinkage side of the hydraulic cylinder can be comprehensively determined by the pressure of the return piping, so that the pressure of the return piping is detected by a return piping pressure sensor 26, and a necessary absorption torque is determined from the pressure of the return piping in a controller 23, and thus the pump flow rate based on the necessary absorption torque is commanded to pump regulators 21 and 22. COPYRIGHT: (C)2011,JPO&INPIT |
