Patent attributes
The seal ring is annular around an axis x and includes an annular outer peripheral surface facing an outer periphery side, and a plurality of recessed parts. The recessed parts are formed in such a way as to be spaced apart from each other in a circumferential direction and are recessed from the outer peripheral surface toward an inner periphery side. The recessed parts expand, in the axis x direction, from one side surface to a position which does not reach another side surface. The outer peripheral surface includes a annular contact surface between the another side surface and the position, and rib surfaces respectively between mutually neighboring recessed parts in the circumferential direction. Each of the rib surfaces extends between the one side surface and the position in the axis x direction.