| 摘要 |
PURPOSE:To enable both handling operation and lift control under optimum conditions, by operating a lift control valve during the stop time of a handling control valve in the operation of a lift control valve when a handling control means is in a state to drive a handling control valve. CONSTITUTION:A lift control means 100 drives control valves 10A, 10B for lifting and a handling control means intermittently drives a handling control valve 11 according to the operation command to keep the working vehicle at a target height. When a handling control valve 1 is in a working position in the lifting operation of a hydraulic cylinder 3 for lifting and when the handling control valve 11 is manually operated in the working position over a prescribed period, a lift controlling means 100 repeatedly operates a main control valve 10A between a state to introduce a hydraulic oil to a hydraulic cylinder 3 for lifting and a state to introduce the oil to a handling control valve 11. When the handling controlling valve 11 is operated for a time shorter than the preset time by a control means 101 for handling, the main control valve 10A is operated during the stop period of the handling control valve 11 to a state to introduce the hydraulic oil to the hydraulic cylinder for lifting.
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