Quartz analog movement with lavet stepping motor and large energy cell
US4744066A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 6, 1987 |
| Grant date | May 10, 1988 |
| Priority date | — |
| Expiry date | Jul 6, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04C13/11
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A movement for a three hand quartz analog timepiece has an energy cell supplying power to a timekeeping circuit which periodically steps the rotor of a Lavet type stepping motor. The stepping motor rotor drives a "seconds" wheel assembly attached to the "seconds" hand spindle through one or more intermediate wheel assemblies of gear, pinion, and spindle. A first intermediate wheel spindle of non-magnetic material is journaled such that its axis extends through the circumferential gap carrying magnetic flux between the rotor and the stator of the stepping motor. Several alternative means of journaling the first intermediate wheel assembly within the active flux gap of the stepping motor are shown and described, as well as movements having two intermediate wheel assemblies. The arrangement allows a small diameter "seconds" wheel and a relatively large energy cell, which provides a long running time for the movement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.