Electronic watch with means for detecting the movement of a hand through a reference position
US4420263A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 1982 |
| Grant date | Dec 13, 1983 |
| Priority date | — |
| Expiry date | Dec 15, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G7/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
For performing a very precise detection of the position of at least one hand, the watch is provided with an electro-optical detection device. The detection device comprises a wheel 8 carrying a mirror 26. The wheel 8 is intermittently driven by the driving member 6 for defining n angular positions of the mirror 26. The member 6 is meshing with the gear train 12 of the watch. It further comprises a light emitter 30 and a light receiver 32 which receives a light beam when the mirror 26 is in an angular position corresponding to the reference position of the hand. The number n is inferior to the number of steps performed by the hand during a complete revolution of said hand.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.