Spring-driven watch movement - operates with rotating crank acting as hammer and crank pin fitting into slotted disc

摘要

The watch movement has a mechanical hammer for the balance system provided by a rotating crank. The crank pin (12) fits into a slot (13) in a rotatable disc (14). The opening (13) has almost the same width as the radius of the disc (14) and the crank lies in a plane parallel to that of the disc (14). One side (19) of the slot (13) lies along a radial line while the other side (20) is concave. The disc (14) may have a similar slot (18) diametrically opposite the first into which a spring tongue fits. The spring tongue attached at an adjustable point to the movement mounting plate.