Rotary damper, in particular for an actuating member in motor vehicles, comprising a housing having a cylindrical damper chamber, a liquid viscous medium within the chamber, a rotatably supported shaft within the chamber having at least one substantially radially extending vane such that upon rotation of the shaft, displaced medium flows between a narrow passage between the cylindrical wall of the chamber and the free end of the vane, at least a radially outer portion of the vane being inclined with respect to a diameter extending through the base of the vane and in the circumferential direction and being bendable such that upon a rotation of the shaft in the inclination direction the vane is bent towards the cylindrical wall and upon an opposite rotation the vane is bent towards the shaft, wherein at least one locking cam is provided at the cylindrical wall of the chamber which extends radially inwards and is adapted to be engaged by the free end of the vane if it is bent towards the cylindrical wall a predetermined extent.