Patent ID: 8123229

Claim:
A sealing device comprising: a monolithic resin seal main body installed in an annular gap between an operation member and a fixed member, said resin seal main body including: an approximately cylindrical concave portion which is open to face to a first sealed fluid side; a first inner peripheral seal lip and a first outer peripheral seal lip which are integrally provided at inner and outer peripheries of said cylindrical concave portion and slidably contact with said operation member and said fixed member, respectively; and a plate-shaped second inner peripheral seal lip which is positioned at a second sealed fluid side opposite in an axial direction to the first sealed fluid side and extends diagonally in an inner peripheral direction toward the second sealed fluid side, an inner peripheral side end portion of said second inner peripheral seal lip slidably contacting with said operation member; an elastic body installed to said cylindrical concave portion of the resin seal main body; and a tapered surface extending diagonally relative to said fixed member, wherein said second inner peripheral seal lip and said tapered surface are configured such that an outer peripheral side end portion of said second inner peripheral seal lip directly contacts said tapered surface at a time when a pressure is applied from the first sealed fluid side, and resultant contact surface pressure in the inner peripheral direction is applied to the inner peripheral side end portion of said second inner peripheral seal lip.