US Patent 10359114 Sealing device

A sealing device includes a seal ring 200 made of resin which is in close contact with a side wall surface on a low pressure side of an annular groove 410, and slides against an inner peripheral surface of a shaft hole in a housing 500 through which a shaft 400 is inserted. A metal spring 300 presses the seal ring 200 toward an outer peripheral surface side, wherein a concave portion 220 is formed on an outer peripheral surface of the seal ring 200 which extends from an end portion on a high pressure side of the outer peripheral surface to a position which does not reach an end portion on a low pressure side of the outer peripheral surface, and introduces a fluid from the high pressure side.