Winding crown for e.g. wrist watch, has torque limitation device with ring including cavities which have friction units pushed, by its respective spring, against roller parallel to axis of crown

摘要

The crown has a torque limitation device with a driving ring (2) and a transversal roller (30) for controlling torsion of a mainspring of a clock piece. The ring has multiple cavities (20) with springs (22) and associated friction units (24). Each friction unit is pushed, by its respective spring, against the roller parallel to an axis (4) of the crown. The cavities are regularly distributed around the axis of the crown. An independent claim is also included for a mechanical clock piece with a winding crown.