WORKING ARM CONTROL DEVICE OF A WORKING MACHINE

摘要

A device for controlling a working arm of a working machine, which is capable of releasing the pressure of the actuation fluid confined in the actuation cylinder of the working arm device at a predetermined pressure lower than the set pressure and of controlling the opening/closing of the cylinder relief valve. The device comprises releasing means for a releasing a pressurized fluid feed/drain circuit of an actuation cylinder of a working arm device at a predetermined pressure lower than a set pressure of a cylinder relief valve provided for said feed/drain circuit and a control means for controlling the opening/closing of the releasing means. <IMAGE>