To provide a seal member that can reduce sliding resistance, can suppress an intrusion phenomenon of an elastic member and can maintain versatility of the elastic member.SOLUTION: The present invention resides in a sealing member, which is disposed in an annular groove 8 and comprises an annular elastic member 91 that has a pressure receiving surface 911 for receiving hydraulic pressure of a hydraulic chamber 132 and a back surface 912 opposite to the pressure receiving surface 911, and an annular backup ring 92 disposed to face the back surface 912. The backup ring 92 has a body portion 921 and a protrusion portion 922 that protrudes from the body portion 921 to the hydraulic chamber 132 side and abuts on the elastic member 91 at least in a high pressure state. The protrusion portion 922 has a sliding surface 922a that abuts on a non-grooving surface at least in a high pressure state, and a tapered surface 922b that is on a radially-opposite side to the sliding surface 922a. The tapered surface 922b is inclined to approach the non-grooving surface as separating from the body portion 921.SELECTED DRAWING: Figure 2
【課題】摺動抵抗を低減可能なシール部材において、弾性部材の入り込み現象を抑制でき且つ弾性部材の汎用性を維持できるシール部材を提供する。【解決手段】本発明は、環状溝8に配置されるシール部材であって、液圧室132の液圧を受ける受圧面911と、受圧面911とは反対側の面である背面912と、を有する環状の弾性部材91と、背面912に面するように配置される環状のバックアップリング92と、を備え、バックアップリング92は、本体部921と、本体部921から液圧室132側に突出し且つ少なくとも高圧状態で弾性部材91に当接する突出部922と、を有し、突出部922は、少なくとも高圧状態で非溝形成面に当接する摺動面922aと、摺動面922aに対して径方向の反対側の面であるテーパ面922bと、を有し、テーパ面922bは、本体部921から遠ざかるほど非溝形成面に近づくように傾斜している。【選択図】図2
SEAL MEMBER
シール部材
2021-08-26
Patent
Elektronische Ressource
Japanisch