CAM

Retrograde display cam

The cam is a rotating mechanical part whose eccentric or irregular profile transmits a movement controlled to a follower (roller, feeler, tip, lever) in contact with it. It generally converts continuous rotary motion into reciprocating or intermittent motion, whose displacement law is entirely defined by the shape of the profile. In watchmaking, cams are ubiquitous: in striking mechanisms, they control the number of strikes; in retrograde displays, the jumper cam defines the abrupt reset of the Hand; in chronographs, the shuttle (cam) directs the start, stop, and reset levers. They are also used to program the action of many machines such as automatic lathes or Lathe for To guilloché. The precision of a cam’s profile — generally machined by Electrical discharge machining (EDM) or Milling high resolution — directly determines the reliability and smoothness of the complication it drives.