PURPOSE: To obtain a high seal performance by composing a seal device, sealing a space between a cylinder and a rod-shaped piston inserted in the cylinder, of a backup ring and two seals including an O-ring disposed on inside and outside a flange in an axial direction thereof.
CONSTITUTION: A pup device discharges a high pressure fluid from a chamber 18 formed in a cylinder 18 through a valve assembly (not shown) provided on a front end of the cylinder 14, when a piston 16 is compression-stroked by a suitable drive element. A space between the cylinder 14 and the piston 16 is sealed by a seal assembly 12, in this case, the seal assembly 12 is composed of a backup ring 30 comprising a locating flange 32 extending in an axial direction, a first seal 34 consisting of a seal sleeve 36 and an O-ring 38, and a second seal 40 consisting of an O-ring 42 and a face seal member 44. On a front part of the flange 32, a groove 88 forming a pressure relief passage for the O-ring 38 is formed.
ORIBUIA ERU TOREMOORETSUTO JIY
SHIGAADO SHII MOODORU
| JPS5088452A | 1975-07-16 |
| US4674754A | 1987-06-23 | |||
| GB966561A | 1964-08-12 |