| 摘要 |
<p>A sealing device (1) in which a shaft insertion load is reduced and in which, even if a high-pressure fluid is applied to the device, a function of preventing a seal ring from being extruded to the low pressure side is secured. The sealing device (1) has a seal ring (20) and a backup ring (30). The seal ring (20) is positioned in an installation groove (10) formed in the shaft (2) and having a tapered groove bottom section (12). The backup ring (30) is positioned closer to the low-pressure side (L) than the seal ring and has a tapered section (35) corresponding to the tapered groove bottom section (12). A gap (g) is provided between a side wall surface (11) of the mounting groove (10) and a side end surface (32) of the backup ring (30), where the side wall surface (11) is on the low-pressure side (L) and the side end surface (32) is on the low-pressure side (L). Further, a tapered surface (36) is formed on the peripheral surface (34) of the backup ring (30), where the peripheral surface (34) is on the opposite side of the tapered section (35). When pressure from the high-pressure side (H) acts on the sealing device, the tapered surface (36) moves toward the low-pressure side (L) from a side end surface (31) on the high-pressure side (H) to approach a peripheral surface (3a) of a housing (3). The tapered section (35) is formed as a two-staged taper surface.</p> |
