Patent ID: 8659177

Claim:
A motive power regeneration system for a working machine comprising: an operating apparatus that outputs an operation signal according to an operation amount; a hydraulic cylinder that performs a telescopic operation in accordance with the operation signal output from the operating apparatus; a hydraulic pump that is driven by an engine to supply a hydraulic fluid to the hydraulic cylinder; regeneration means that converts to an electrical energy the energy of the returning fluid from a bottom side hydraulic chamber of the hydraulic cylinder; a regeneration circuit that is connected to the hydraulic chamber to introduce the returning fluid from the hydraulic chamber to a tank through the regeneration means; a flow regulating circuit that is connected to the hydraulic chamber to introduce the returning fluid from the hydraulic chamber to the tank; a detector that detects the operation amount of the operating apparatus; first flow control means that controls the flow rate on the regeneration circuit in accordance with the operation amount detected by the detector and with a first flow rate setting which varies with the operation amount of the operating apparatus; and second flow control means that controls the flow rate on the flow regulating circuit in accordance with the operation amount detected by the detector and with a second flow rate setting which varies with the operation amount of the operating apparatus.