| 摘要 |
PROBLEM TO BE SOLVED: To provide a watch movement for a mechanical watch having an extremely extended operation power reserve and to increase the operation power reserve.SOLUTION: A watch movement and a mechanical watch include a device which reduces a vibration amplitude of a balance by reducing a torque given by a barrel with a result that a power reserve for the operation of a movement is extended, and in which an extension ratio is defined according to the characteristics of the watch in such a manner that a user recognize that, after the elapse of several days, one week, or over a time beyond that, a date display is updated without winding the watch during that time and his/her own watch is in an operation state. A torque change device is simple and easy to manufacture. This is because an access can be made outside of the watch. An operation state can be marked by a visible needle outside of the watch. |
