Detection device of electronic timepiece
US4321521A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1979 |
| Grant date | Mar 23, 1982 |
| Priority date | — |
| Expiry date | Dec 4, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P8/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electronic timepiece has a stepping motor comprised of a stator, rotor and driving coil. A wave shaping circuit produces normal driving pulses and correction driving pulses having a longer pulse width than the normal driving pulses. A rotor rotation detection device detects rotation and non-rotation of the rotor after normal driving pulses are applied to the driving coil and in response to detection of a non-rotation condition, a correction driving pulse is applied to the driving coil. A magnetic field detection device detects the presence and absence of an external alternating magnetic field and in response to detection of a magnetic field, a driving pulse of longer pulse width than the correction driving pulses is applied to the driving coil to effect rotor rotation. The magnetic field detection device operates before the normal driving pulses are applied to the driving coil so that in the event of detection of a magnetic field, a driving pulse of sufficiently long pulse width will be applied to the driving coil to effect rotor rotation. In response to detection of an external alternating magnetic field by the magnetic field detection device, operation of the rotor rotation de…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.