| 摘要 |
PURPOSE:To improve operational efficiency by making it possible to switch a oil chamber consisting of the ends of a spring receiver and a receiver body to a pipe line led to the oil pressure source and to a pipe line led to a tank and reducing the inflow of oil to an actuator. CONSTITUTION:The discharge pressure oil of a pilot pump 2 to be the operation system oil pressure source is led to a selector valve 22 through a pipe line 10, at E position of the valve 22 the pipe line 10 is led to a pipe line 11 leading to a receiving section (e) of a flow regulator valve 5, and at F position the pipe line 11 is led to a tank 13. And, an oil chamber 27 is constituted of a spring receiving surface 26 of the regulator valve 5 and the internal circumferential surface of a receiving section body 14. In a fine control system, the pipe line 10 is cut off when the valve 22 is the F position, and since the oil chamber 27 is led to the tank 13, the spring receiver 26 moves in the right direction, the setting load of a negative control spring 18 is reduced, and the discharge oil quantity of a main pump 1 is reduced. Accordingly, the inflow to an actuator is reduced, and the fine operational efficiency is improved. |
