Watch indicating time in more than one time zone - uses supplementary 12-hour wheel on manually operable ring which drives day-and-night indicator disc

摘要

The hour hand (2) co-operates with fexed and movable 12-hour wheels carried on a manually operable ring (9) which can be set to show the time in any selected zone. A day-and-night indicator is constituted by a disc (19) carrying symbols which are visible through a window (20) in the dial. The disc forms the cage of a differential gear and carries three satellite pinions (21) in mesh with a planetary wheel (22) integral with the hour wheel (23). The pinions also engage the interior teeth (24a) of a planetary ring (24) geared to the ring, which drives the disc while the planetary wheel can be considered as stationary. The day-and-night indication is corrected simultaneously. ADVANTAGE - Watch is practical, reliable and easy to mfr.