Patent · US Expired

Stepping motor drive system and method capable of stopping the rotor in a required angular position

US4697129A · kind A · utility

54Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 13, 1986
Grant dateSep 29, 1987
Priority date
Expiry dateFeb 13, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P8/32
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In a stepping motor of the type having one or more sets of four phase windings on respective stator poles, with the four phase windings being excited sequentially to cause the rotation of a rotor having magnetic poles, a drive method and system are disclosed for stopping the rotor in exact angular positions required. Since the stator can less magnetically control the rotor when the latter is positioned with its magnetic poles in axact alignment with the stator poles, the stator windings are sequentially excited in such a manner that upon termination of the sequential excitation, the rotor comes to a stop in a position angularly displaced to a predetermined degree in a predetermined direction from a position of exact alignment with the stator poles. Basically, for stopping the rotor in such angular positions, at least two of the four phase windings are excited at a time with currents of predetermined different magnitudes.

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