Reduction gear for electronic timepiece
US4357695A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 1980 |
| Grant date | Nov 2, 1982 |
| Priority date | — |
| Expiry date | Jul 17, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/19949
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pinion of a reduction gear intended for use in electronic timepieces having a stepping motor, particularly wrist watches, takes the form of a cylindrical body having an axial blind hole and two teeth milled at one end of the body. The flancs of the teeth are plane parallel surfaces. The distance between the axis of rotation of the pinion and the axis of rotation of a toothed wheel of the reduction gear is slightly less than the radius of the tip-circle of the wheel, so that the two teeth of the pinion block the wheel during the resting period of the motor. If a wheel with 60 teeth is used, it may constitute the fourth wheel in an electronic watch having hands.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.