TRAVEL OPERATION CIRCUIT FOR WORKING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a travel operation circuit for working machine capable of driving a hydraulic motor in a state of suppressing a starting shock while having a counter balance valve. SOLUTION: The counter balance valve 20 is provided with an oil discharge port 20a which communicates with a supply side oil passage 28 when the counter balance valve 20 is switched to an opening position O. The oil discharge port 20a is connected to an operational oil passage 11 through a cushion oil passage 30 having an opening and closing valve 32 and a restricting part 31. A pilot operational oil passage 33 is connected to the opening and closing valve 32. The pilot operational oil passage 33 operates the opening and closing valve 32 to be in a state of closing by a pilot pressure from the operational oil passage 11 after the counter balance valve 20 is switched to the opening position O.