Compagnie Des Montres Longines, Francillon S.a.

Michel Groothuis

Michel Thomi

Serge Meylan

Analog display calendar watch having a window or windows and an hour spindle changing device in which the movements of the hour hand and the disc or discs of the calendar are synchronized. The calendar disc is driven once every 24 hours by a rocker lever which supports a plate having a catch engaging the calendar disc, the plate being rotated by a 24-hour wheel and effecting a whole number, greater than one, of turns in 24 hours. The width of the catch is slightly less than the space between two teeth of the calendar disc, so that any forward or backward movement of the hour hand, controlled by the hour setting spindle, permits an immediate forward or backward movement of the calendar disc.

Growing community of inventors

St.-Imier, Switzerland

Michel Groothuis