YOKE

A yoke is a pivoting component with one or more arms or levers, capable of locking into several precise positions throughout its range of motion. It is a common type of component in watch movements. The most widespread example is the yoke of the time-setting mechanism, which moves the sliding pinion (or clutch wheel) between the winding and time-setting positions. In chronographs, the yoke, actuated by the column wheel or cam, engages and disengages the chronograph mechanism.

Useful links:
– Time-setting mechanism
– Time-setting yoke
– Short-time interval measurement (chronographs)