HYDRAULIC DRIVING DEVICE OF WORKING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic driving device of a working machine, which is capable of ensuring good operability during a normal operation and during a minor operation and reducing energy loss during the minor operation.

SOLUTION: The present invention has a configuration in which a controller 31 includes: a pump discharge amount control unit 40 which performs control processing in which when the operation mode of a working element operation device is an operation mode regarded as a minor operation, a control signal for making the displacement of a variable capacity hydraulic pump 10 smaller than a displacement corresponding to a normal operation is output to a control unit of an electromagnetic proportional pressure reducing valve 21; and a center bypass valve control unit 50 which performs control processing in which when the operation mode is an operation mode regarded as the minor operation and the load pressure of a working element actuator is low, a control signal for making the amount of opening relatively larger while a center bypass valve 22 is in a state of switching between a fully open position and a fully closed position is output to a control unit of a proportional electromagnetic valve 23.

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