POWER REGENERATION DEVICE FOR OPERATING MACHINE

摘要

A power regeneration device for an operating machine has a hydraulic cylinder and a return line through which fluid returning to a tank flows when the hydraulic cylinder contracts. The return line branches into a plurality of hydraulic lines through a branching part and includes a regeneration line that which leads returning fluid to the tank via a hydraulic motor to which a generator is connected. A control valve line is connected to the branching part and leads the returning fluid to the tank via a control valve. An electricity storage device stores electric power generated by the generator, and an electric amount detector detects the electric amount of the electricity storage device. A flow rate calculator calculates the flow rate of the returning fluid flowing through the regeneration line and the flow rate of the returning fluid flowing through the control valve line depending on an electric amount signal.