Patent · US Expired

Electronic watch

US4241433A · kind A · utility

9Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 24, 1978
Grant dateDec 23, 1980
Priority date
Expiry dateJul 24, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG04C3/143
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In an electronic watch a non-operation detecting circuit detects the non-operative condition of the stepping motor of the watch and produces a non-operation signal each time the stepping motor fails to operate in response to the standard pulse which drives the same. A counter counts the number of non-operation signals and stores the count for later use. A rotation detecting circuit detects the resumption of operation of the stepping motor in response to the standard pulse from the non-operative condition and a quick feed control circuit quickly advances the stepping motor in response to an input from the rotation detection circuit by thereafter supplying, instead of the standard pulses, the quick feed pulses to the drive circuit for the motor equal in number to the number of the non-operation signals counted in the counter. In this way the corrected time will be displayed by the watch even after being rendered inoperative as a result of an external condition such as low temperature or a high strength DC magnetic field.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.