To prevent protrusion of a waist part of a main lip toward an inner peripheral side by a large pressure load to be applied to the main lip by the inner pressure on a sealing side.
This sealing device is structured by swelling a part formed from a connection part of a sealing device for reciprocating shaft, in which a main lip on a sealing side to be brought in slide-contact with a reciprocating shaft by an elastic body fitted in a metal reinforcing ring and a dust lip on an air side are integrally formed with each other through the connection part along the inner periphery of the reinforcing ring, toward the reciprocating shaft. Even if a large pressure load is applied to the main lip from the sealing side by the swelled part, it is hard to generate deformation with high tensile force near a waist part of the main lip. The length of the main lip is formed shorter than that of a conventional one, and an area receiving the pressure on the sealing side can be thereby reduced, and contact force of the lip to the reciprocating shaft can be restricted.
SATO YUTAKA
SEKI SHINYA
UMEZAWA ATSUHIRO
