| 摘要 |
PURPOSE:To prevent a caterpillar vehicle from traveling with curving by providing a control force adding means, at one of left or right traveling direction control valves, for applying control force for supplying flow volume which is added half of the maximum discharge volume of a main hydraulic pump to a diversion compensation valve. CONSTITUTION:Diversion compensation valves 36, 37 are installed at a left traveling direction control valve 30 and a right traveling direction control valve 31 respectively. A control pressure adding means 52 having a differential pressure detecting means 53, controller 59 and control pressure generation means 60 is installed. Control force for supplying flow volume which is added 1/2 of the maximum discharge volume of a main hydraulic pump 22 to predetermined volume to one of the left and right traveling direction control valves is applied to the driving unit of diversion compensation valves 36, 37. Accordingly, curving travel due to the manufacturing error of the left and right traveling direction control valve can be prevented and also the labor of an operator is reduced when one of caterpillars runs on earth and sand, etc. |
