| 摘要 |
PURPOSE:To enable to fulfil high precision flow rate regulating function without making the valve larger all over or using higher compensating pressure by a method wherein an influence exerted upon the accuracy of flow rate regulation is eliminated by reducing the fluid force applied to the spool of a pressure compensation part. CONSTITUTION:At least one row of through holes 16a are bored on the peripheral wall of a hollow chamber 16 normal to said wall and the through holes in each row are disposed in the longitudinal direction of the spool 12. The amount, which is predetermined in proportion to the opening area of a variable throttling part 8, of fluid sent by a constant delivery pump 1 is past through the through holes 16a, the hollow chamber 16 and through holes 16b and, after that, past through the variable throttling part 8 and then extracted to a reservoir tank 10. At this case, the total opening area of the through holes 16a is adjusted by shifting the spool 12 longitudinally. Accordingly, the flow rate regulating function, which consists in determining the extraction amount of fluid under the condition that the difference between the pressures before and after the variable throttling parts 8 is kept at the set value by the opening area of the variable throttling part 8, can be done highly accurately. |
