To provide a sealing device which effectively reduces the dragging torque without employing any special section even when a seal ring is formed of an inexpensive material.
A recessed part 23c which is constantly communicated with a recessed groove 23 is formed in a part of a side wall 23a of the recessed groove 23. A part 21d1 of a side surface 21d of the seal ring 21 of rectangular section formed of Teflon (registered trademark) is tightly fitted to the side wall 23a, a part 21d2 of the side surface 21d is not tightly fitted to the side wall 23a, and the contact area is reduced. A part of the hydraulic pressure applied to the side surface 21a of the seal ring 21 is canceled by the hydraulic of the recessed part 23c applied to the part 21d2 of the side surface 21d of the seal ring 21, and the pushing force of the seal ring 21 by the hydraulic pressure applied to the side surface 21a is reduced. The dragging torque between the seal ring 21 and the side wall 23a of the recessed groove 23 is reduced thereby.
YOSHIKAWA HIROSHI
KANEDA TOSHIKI
NOZAKI KAZUTOSHI
| JPH08219292A | 1996-08-27 | |||
| JPS61136062A | 1986-06-23 |