Patent · US Expired

Efficient permanent magnet electric motor

US5258697A · kind A · utility

62Cited by
23References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 1991
Grant dateNov 2, 1993
Priority date
Expiry dateOct 23, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/70
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An electric motor, of the type that includes a rotor with permanent magnets and a stator with electromagnets, which operates at high efficiency to produce a high ratio of mechanical power output to electrical power input. During rotor rotation in a first direction (74, FIG. 5), a first magnet (44A') moves away from a position of alignment with the core of a "last" electromagnet (46A), while a second permanent magnet (44B') moves toward a position of alignment with the core of a "next" electromagnet (46C) which it is approaching. The last electromagnet (46A) is energized in a direction to negate attraction of its core (50) for the first permanent magnet (44A'). The next electromagnet (46C) is not substantially energized, so the attraction of the second magnet for the next electromagnet (46C) is due primarily to attraction of their cores in the absence of energization of the next electromagnet. Thus, most electrical power supplied to the electromagnets are to negate attraction between a permanent magnet and the last electromagnet which the permanent magnet is moving away from. This allows most motor output torque to arise from the attraction of permanent magnets for the cores of unen…

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