Perpetual calender for analogue watch - includes index wheels controlling advance of calendar at month end according to month length

摘要

The watch mechanism includes a perpetual calendar, with a calendar display wheel (6) controlled by a 24-hour wheel (2a,2b) operating in two stages. This is itself controlled by the hour wheel (1). The calendar wheel includes a further gear complex including three wheels (19,20,23). According to the angular position of the three wheels, steps of zero, one, two, three or four days may be imposed. These steps are effected at the end of the month according to the month length varying between 28 and 31 days. ADVANTAGE - Automatic accommodation of varying month lengths in analogue mechanical watch.