Timepiece driven by a source of mechanical energy and regulated by an electric circuit
USRE36733E · kind E · reissue
Assignee
Inventor
Key dates
| Filing date | May 12, 1998 |
| Grant date | Jun 13, 2000 |
| Priority date | — |
| Expiry date | May 12, 2018 |
Classification
- Technology area (CPC —)General
Abstract
The hands of the timepiece are connected to a barrel spring which also drives the rotor of a generator at a speed greater than a desired speed Vc. The electric energy supplied by the generator energizes a slaving circuit that includes a transistor which short-circuits the coil of the generator and thus brakes the rotor down to a speed less than the desired speed Vc when a comparator indicates that this rotor is ahead with respect to its theoretical angular position. A limiting circuit limits the duration of the braking action of the rotor to a fraction of the period of the a.c. voltage supplied by the generator. This arrangement ensures that the slaving circuit is adequately energized even if the rotor is substantially ahead.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.