Patent · US Expired

Driving device for a stepping motor

US4734632A · kind A · utility

13Cited by
2References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 1986
Grant dateMar 29, 1988
Priority date
Expiry dateSep 26, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P8/14
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A driving device for a stepping motor wherein detection of a position of the rotor of a stepping motor can be effected accurately without the necessity of adjustments of various elements. The device detects a current flow in a field winding of an energized phase and compares it with a simulated saturation curve to detect a back EMF induced in the winding to find a current position of the rotor of the motor. The simulated saturation curve is produced by energizing the winding with a low voltage, measuring current flows in the winding as voltage signals at three different points of time, and calculating several data indicating a saturation curve from the voltage signals. The data are stored in memory and recalled one after another to produce a corresponding voltage when the field winding is energized.

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