Oil seal

Abstract

An oil seal or fluid seal for providing a seal between a cylinder and a piston rod is provided. The oil seal has an annular seal lip which has on a conical inner circumferential surface thereof a plurality of annular projections which are arranged axially of the seal lip. One of the annular projections which is located more axially outside of the cylinder is larger in the height above the inner circumferential surface than one of the annular projections which is located more axially inside of the cylinder. By this, under a condition where the annular projections which are located more axially inside of the cylinder are subjected to a high pressure within the cylinder, the annular projections which are located more axially inside of the cylinder and the annular projections which are located more axially outside of the cylinder are nearly equal in the contact pressure against the piston rod, thus causing all of the annular projections to deform nearly equally. The annular projections are all brought into contact with the piston rod at nearly equal contact areas.

Dependencies are inferred from the claim text.