Synchronous motor for timepiece
US4386287A · kind A · utility
12Cited by
3References
4Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Feb 23, 1981 |
| Grant date | May 31, 1983 |
| Priority date | — |
| Expiry date | Feb 23, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K21/185
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A synchronous motor for a timepiece capable of cancelling unbalance in self-starting driving power with regard to the oscillating direction at the time of self-starting, in which adjoining stator pole pitch angles are set at 0.5 times or 1.5 times the rotor pole pitch angle. Provision of specific directional performance is restricted to direction of self-starting rotation. The air gap between the stator supplementary poles and the rotor is set at a ratio between 1 and 1.4 against the air gap between the stator main poles and the rotor; width of the stator supplementary poles is wider than the stator main poles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.