| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent wear of a bore inner wall due to eccentric pressure distribution of a hydraulic control valve.SOLUTION: A hydraulic control valve 1 opens/closes a groove 13 formed on an inner wall of a bore 3 in communication with an output port 12 by sliding a second land 21 of a spool 20, so as to control a flow rate of hydraulic oil from an input port 10 to the output port 12. The second land 21 is divided into an adjustment land part 22 for changing an opening amount of the groove 13 in a ring-like notch space r, and a seal land part 24. The adjustment land part 22 has axial length smaller than axial width of the groove 13, and the notch space r forms a relaxation chamber R2 on a rear side of the adjustment land part 22 together with the groove 13. The hydraulic oil directed to the output port 12 through an opening between the groove 13 and the adjustment land part 22 moderately flow by the relaxation chamber R2, and therefore, it is difficult to cause pressure eccentric distribution. A spool is not pressed in a specific direction in the pressure eccentric distribution, and therefore, wear of the inner wall of the bore 3 is prevented.</p> |
