An exterior rearview mirror assembly comprising:
- a pedestal mounted to a vehicle and having an axial joint part, the axial joint part having a plurality of first convex portions facing downwardly, a plurality of first concave portions facing downwardly, and a plurality of an inclined guide surfaces each located between every adjacent said first convex and concave portions, the first convex and concave portions being arranged alternately around an axis annularly;
- a mirror holder having at least one mirror;
- a coupling member having two ends, one of which is connected with the mirror holder and the other is a pivotal portion rotatably mounted to the pedestal around said axis, the pivotal portion having an axial hole and a spacer located inside the axial hole, the spacer having a central hole and at least one perforation;
- a sleeve located below the spacer and movably mounted inside the axial hole for movement between an engagement position and a disengagement position, the sleeve having a top end, a bottom end and a plurality of first teeth, the first teeth being arranged annularly on the top end around the axis and being inserted through the perforations;
- an engagement member mounted between the spacer and the axial joint part and at a top side thereof having a plurality of second convex portions, a plurality of second concave portions, and a plurality of inclined guide surfaces located between every adjacent said second convex and concave portions, the second convex and concave portions being arranged alternately around said axis annularly for engagement with the first convex and concave portions, the engagement member further having a plurality of second teeth formed at a bottom side thereof and arranged annularly around said axis;
- a first screwed fastener having a head end and threaded end and passing through the central hole of the spacer and making the threaded end be threaded with the axial joint part;
- a limiting member mounted to the first screwed fastener;
- and
- a springy member held between the limiting member and the pivotal portion for providing the spacer with elastic prestress facing upwardly;
- wherein, when the sleeve is moved to the engagement position, the first teeth are engaged with the second teeth;
- when the sleeve is moved to the disengagement position, the first teeth are disengaged from the second teeth.