Patent attributes
A labyrinth seal suppresses leakage of fluid through a gap between a circumferential outer surface of a rotating body, having an axis of rotation, and a circumferential inner surface of a stationary body provided on an outer side of the rotating body, by increasing fluid energy loss caused by vortices. Said leakage occurs in an axial direction from a high pressure to a low pressure side. A step is formed on the outer surface such that the diameter of the low pressure side is smaller than that of the high pressure side. A fin extending radially inward from the inner surface is formed on at least the low pressure side of the step. An annular groove is formed to extend in a circumferential direction in the outer surface, in at least one portion of the area axially between the step and the fin.
