Patent ID: 7575108

Claim:
A damper comprising: a cylindrical housing; a rotor rotatably disposed in the housing, and having a cylindrical shaft portion and a wing portion radially outwardly extending from the shaft portion; a control valve member disposed between the housing and the shaft portion to cover the wing portion; and a viscous fluid filled inside the housing; wherein the wing portion has an asymmetric shape with respect to a rotational direction of the rotor relative to a straight line extending radially from the shaft portion; the wing portion includes a tip side surface located on a tip side in the rotational direction when the rotor rotates in a damping torque generating direction, said tip side surface forming a sloping surface sloping rearwardly in the rotational direction from an inside to an outside radially of the rotor; and a back end side surface located on a back end side in the rotational direction when the rotor rotates in the damping torque generating direction, said back end side surface forming a flat surface which runs parallel to the straight line extending radially of the rotor; and the control valve member includes a first inner surface facing the sloping surface parallel thereto, and a second inner surface facing the flat surface parallel thereto.