| 摘要 |
<p>PROBLEM TO BE SOLVED: To keep a fluid from decreasing by making the fluid leaking from between the sliding surfaces of a seat ring and a driven ring unlikely to leak outside. SOLUTION: A microclearance 28 is provided between the outer peripheral surface of a rotating shaft 3 and the inner peripheral surface of the guide cylinder part 16 of a support cylinder 14 secured to a housing 1. Grooves 27, 27 for producing dynamic pressure are formed in the portions of the outer peripheral surface of the rotating shaft 3 which are opposite to the microclearance 28. While the rotating shaft 3 is rotating, pressure in the middle of the microclearance 28 builds up due to the action of the grooves 27, 27. As a result, a fluid becomes unlikely to leak outside through the microclearance 28.</p> |
