Patent · US Expired

Control circuit for a stepping motor in battery-operated instruments

US4381481A · kind A · utility

10Cited by

4References

13Claims

0Family size

Assignee

Gebruder Junghans GmbH · DE

Inventors

Frieder Kuppers · Schramberg, DE
Bernhard Scherzinger · Graz, AT
Friedrich Assmus · Schramberg, DE
Hans Flaig · Schramberg, DE

Key dates

Filing date	Nov 6, 1980
Grant date	Apr 26, 1983
Priority date	—
Expiry date	Nov 6, 2000

Classification

Technology area (CPC G)Physics
CPC primaryG04C3/143
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

In a circuit for the actuation of a stepping motor for battery-operated instruments, in particular watches, the length of motor drive pulses is altered for the purpose of saving energy. In the process, different loads on the stepping motor and variable battery voltages are taken into consideration. This feature is accomplished by measuring a signal proportional to the current flowing through the field coil of the stepping motor and interrupting the drive pulse to the motor when a predetermined change occurs in the signal. The drive pulses are further limited as to both minimum and maximum length. Advantageously, the stepping motor is actuated and the signal processed by means of a digital circuit technology, in order to provide for complete integration of the circuit.

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