Watch hairspring and method for making same
US7077562B2 · kind B2 · utility
26Cited by
7References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2003 |
| Grant date | Jul 18, 2006 |
| Priority date | — |
| Expiry date | Oct 30, 2023 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16F2222/02
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The invention relates mainly to a hairspring intended to equip the balance wheel of a mechanical timepiece. It is in the form of a spiraled rod (10) cut from an {001} single-crystal silicon plate. Its structure and its dimensions are calculated so as to minimize the thermal drift of the hairspring/balance-wheel assembly by means of the first and second thermal coefficients of its spring constant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.