Patent ID: 8439172

Claim:
An oil damper for preventing a seat and a cover from rapidly rotating, comprising: a shaft unit having a coupling part coupled to the seat and the cover, and a rotating depression coupled to a rotating protrusion of a housing, the shaft unit rotating to move a cam; the cam rotatably coupled to a rotating shaft of the shaft unit so that when the shaft unit rotates in a direction, the cam moves along a cam part of the shaft unit and compresses an elastic member; a valve provided around the rotating shaft of the shaft unit, the valve opening or closing a coupling hole depending on movement of the cam to allow fluid to flow through the coupling hole or prevent the fluid from flowing through the coupling hole; the elastic member provided around the rotating protrusion in the housing, the elastic member being compressed by the cam, thus generating a repulsive force; the housing coupled to the shaft unit, the housing having the rotating protrusion around which the elastic member is provided, with a flow rate control groove formed in the housing, the flow rate control groove configured to control a flow rate of fluid in response to the movement of the cam; and a fastening member fitted over the shaft unit and fastened to the housing.