Patent · US Expired

Stepper motor

US5448117A · kind A · utility

29Cited by
13References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 25, 1993
Grant dateSep 5, 1995
Priority date
Expiry dateFeb 25, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K41/06
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A stepper motor includes a stator with magnetic poles extending radially outward from a central core to form segments of an outer stator surface, an armature ring fitting loosely over the stator, and a rotor with a drive plate rotationally driven by rollers extending from the armature ring into apertures in the drive plate. Current is supplied, according to a sequence, through coils surrounding each magnetic pole, so that the armature ring, being sequentially attracted to adjacent magnetic poles, moves around the stator with a modified orbital motion including an orbital motion, in which the ring is translated around a circular path, and a rotational motion. The stepper motor may also include a stationary cam plate with a number of peripheral notches, into which the rollers are moved individually by the orbital motion.

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