Patent · US Expired

Electric motor having frequency generator

US4109170A · kind A · utility

38Cited by
7References
13Claims
0Family size

Assignees

Inventors

Key dates

Filing dateOct 19, 1976
Grant dateAug 22, 1978
Priority date
Expiry dateOct 19, 1996

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P3/465
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electric motor having a rotor consisting of a disk-shaped multi-polar magnet circumferentially sectioned to have a plurality of magnetic poles, a stator consisting of a pair of superimposed star-shaped flat driving coils, said driving coils being disposed facing said magnet, said driving coils being arranged to be supplied with respective alternating currents having a phase differential of 90.degree. thereby to drive the disk-shaped magnet, said motor further comprising a speed detecting coil having a plurality of radially disposed generating wire elements, said generating wire elements being disposed within a magnetic field of said magnet and being connected in series, whereby a signal having a frequency corresponding to the revolution speed of said disk-shaped magnet is induced in said speed detecting coil.

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