Vehicle mirror power fold mechanism

A power fold mechanism for an external rear view mirror assembly to be fitted to a motor vehicle, the mirror assembly having:

• a mirror base mountable to a vehicle;
• a mirror head frame rotatably mounted to the mirror base for rotation about a mirror head axis;
• a detent operably interposed between the mirror base and the frame, the detent having a drive position and a park position;
• a spring acting between the frame and the base in a direction parallel to the mirror head axis, the spring for holding the detent engaged in the detent positions,
• the power fold mechanism comprising:
• a housing engagable by the spring so as to bias the mechanism towards the base along the head axis;
• a drive train;
• and a clutch mechanism comprising a pair of opposed clutching faces and an axial displacement means for re-engaging the clutching faces, the axial displacement means translating rotational movement of the drive train to an axial displacement of one of the pair of clutching faces, the axial displacement means comprising:
• a drive disc having a plurality of circumferentially spaced apart axially extending protrusions;
• a ramp disc having a plurality of ramped recesses for receiving respective protrusions;
• and
• a drag spring operably interposed between the ramp disc and the housing,
• wherein rotation of the drive disc creates relative axial movement between the drive disc and the ramp disc as the protrusions follow the ramped recesses while the drag spring resists relative rotation between the ramp disc and the housing.

An external rear view mirror assembly for a vehicle, the assembly comprising:

• a mirror base mountable to a vehicle;
• a mirror head frame rotatably mounted to the mirror base for rotation about a mirror head axis;
• a detent operably interposed between the mirror base and the frame, the detent having a drive position, the detent arranged to breakaway by relative movement between the frame and the base in a direction parallel to the mirror head axis;
• a spring acting between the frame and the base in a direction parallel to the mirror head axis, the spring for holding the detent engaged in the detent positions;
• and
• a power fold mechanism operably interposed between the mirror base and the frame,
• characterised in that the mirror head frame is a unitary component having a mirror base engaging proximal end and a mirror mount supporting distal end, the proximal end and the mirror base mutually shaped to provide the detent, whereby aerodynamic forces from the mirror head are transmitted directly from the mirror head frame to the mirror base, their being only a single interface, between the mirror head frame and the mirror base.