Self-compensating spiral for a spiral balance-wheel in watchwork and process for treating this spiral
US6329066A · kind A · utility
7Cited by
3References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 24, 2000 |
| Grant date | Dec 11, 2001 |
| Priority date | — |
| Expiry date | Mar 24, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This self-compensating spiral for a mechanical spiral balance-wheel oscillator in watchwork or other precision instrument, made of a paramagnetic alloy, contains at least one of the elements Nb, V, Ta, Ti, zr, Hf and is covered with a substantially uniform oxide layer having a thickness greater than or equal to 20 nm, formed by subjecting the said spiral to an anodizing treatment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.