Patent · US Expired

Direct current brushless motor

US5179307A · kind A · utility

84Cited by
17References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 24, 1992
Grant dateJan 12, 1993
Priority date
Expiry dateFeb 24, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P6/30
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The variable speed, reversible, brushless, direct current motor comprises a rotor, electromagnets a switching transistor module and electronic controller module. The rotor is mounted on a shaft with bearings at each end, with a plurality of permanent magnets symmetrically placed thereon in an alternating field pattern. Each electromagnet invokes a magnetic field at two permanent magnet positions to cause rotation of the rotor. The switching transistor module receives power from two power sources to conduct current and energize the electromagnets. The electronic control module supplies alternating voltage to points on the transistor module. The switching waveform is triggered by infra-red pick-ups mounted next to the rotor. In operation, each time an electromagnet is switched in polarity, the rotor rotates thirty-six degrees until the permanent magnets are aligned with the electromagnet. Each time the polarity is switched, the permanent magnet that is aligned is repelled, while the permanent magnet approaching is attracted. The infra-red pick-ups switch at such a time to continue the rotation.

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