Calendar display for mechanical watch has window in dial allowing viewing of figures on first figure ring with window to allow viewing of figures on second figure ring

摘要

The watch has a motion similar to normal practice with the addition of two numbered (10) date rings (12) behind the dial. The first date ring is engraved with the numbers 1-15 and has a window (14) which may be lined up with the window in the dial. Numbers 16-31 on the second date ring are then visible in the window in the dial. The rings have drive teeth (17,17a) on their inner edges. The motion includes a switching wheel (18) with teeth (18a) which may turn the first date ring. An extra short month indicating hand is provided on the dial, coaxial with the hour and minute hands, and is driven by a Maltese cross (34) engaging a pin (36) on the first date ring.