Patent attributes
A seal ring includes a center axis, an outer peripheral surface, an inner peripheral surface, a side surface, and a groove. The center axis is a rotation center. The outer peripheral surface is an outward cylindrical surface whose center is positioned at the central axis. The inner peripheral surface is an inward cylindrical surface disposed between the center axis and the outer peripheral surface whose center is positioned at the central axis. The side surface connects the outer peripheral surface and the inner peripheral surface. The groove is formed in a dented groove from the side surface, extends along a radial direction spaced from the outer peripheral surface, has a first end connected to the inner peripheral surface and a second end at an opposite side of the first end, and returns oil entered from the first end to an inner peripheral surface side via the second end.