| 摘要 |
1,131,205. Date indicators. ETA A.G. EBAUCHES-FABRIK. Feb.4, 1966 [April 20, 1965], No.4965/66. Heading G3T. A calendar watch possessing an instantaneous date changing motion comprises a date indicating ring 7, capable of being driven by the watch movement and an entrainment member 9 carried by a driving spring 8 and operatively engaging the date indicating ring, the driving spring being mounted on a control wheel 5. The control wheel 5 is continuously driven by an hour wheel 2 via a reduction gear 6. The entrainment member 9 engages a tooth 10 of the date ring 7 so that as the wheel 5 rotates, the spring 8 tensions until the entrainment member reaches a rigid portion 20 of a hub 17 which is an integral part of the wheel 5. The force exerted by the spring on the tooth 10 then causes a detent 12, biased by a spring 15, to move out of engagement with another tooth and thereby allow the entrainment member 9 to advance the date ring 7. Reverse indexing of the date ring 7 during backward setting of the ravels is prevented by a cam surface 21 which pulls the entrainment member 9 out of engagement with the teeth 10. |
