| 摘要 |
PROBLEM TO BE SOLVED: To avoid a decrease in seal performance of a pressure reduction valve due to a flaw in a seal member provided on a side wall of a piston.SOLUTION: An O ring 126 as a seal member is mounted in a slide region 119, coming into slide contact with a body 12, in a side wall of a piston 100. The O ring 126 is arranged between a first ring body 128 and a second ring body 130. The first ring body 128 and second ring body 130 are thereby located upstream or downstream from the O ring 126 in a displacing direction. The first ring body 128 and second ring body 130 are made of resin having a lower friction coefficient than the O ring 126, for example, polytetrafluoroethylene resin, polyether ether ketone resin, etc. Alternatively, the resin may be polyamide resin to which a solid lubricant such as molybdenum disulfide is added. |
