| 摘要 |
In a solenoid valve 10 , an annular oil groove 66 is formed at a portion corresponding to a spring chamber 56 on the external surface of a sleeve 19 , a drain passage 68 is formed to make an upper part of the annular oil groove 66 communicate with the outside of an insertion bore 61 , and a throttle hole 67 is provided at a lower part of the annular oil groove 66 for making the annular oil groove 66 communicate with the spring chamber 56 . Since the annular oil groove 66 communicates with the outside of the insertion bore 61 at its upper part through the drain passage 68 , it can be realized to store the operating oil to the height of the upper part of the annular oil groove 66 , so that the operating oil can be reserved in the spring chamber 56 which communicates with the annular oil groove through the throttle hole 67 . Further, the operating oil is supplied from a feedback port 48 next to the spring chamber 56 through a clearance between the spool valve 19 and a valve hole 18 . Thus, the solenoid valve 10 is able to secure the damping effect of the working oil on the spool valve 19 and a plunger 17 and to suppress the self oscillation even while being operated in the atmosphere for a long time.
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