| 摘要 |
PURPOSE:To keep the decreasing property of the rate of flow constant and enhance high-speed stability, by altering and controlling the cross-sectional area of an orifice independently of the displacement of a flow rate regulating spool valve but depending on the increase in the rate of discharge flow of a pump which is caused by the rise in the rotational frequency of the pump. CONSTITUTION:A supply passage 14 and a bypass 15 are opened into a valve fitting hole 11 provided in a pump housing 10. The supply passage 14 is normally connected to the valve housing hole 11 through a restricting passage 16. A spool valve 17, which can disconnect the passages 14, 15 from each other and regulate the cross-sectional area of a communication passage for the passages 14, 15, is provided in the housing hole 11. Valve chambers 18, 19 are defined on both the sides of the spool valve 17. A restrictor 24 is fitted in a union 12 screw-engaged in one end of the housing hole 11. An orifice 25 is provided in the center of the restrictor 24 to connect the valve chamber 18 and an outlet port 23 to each other. The cross-sectional area of the orifice 25 is reduced by a control spool which is moved leftward by oil pressure applied from a pressure inlet port 36. |
