Patent · US Expired

Magnetic bearing device with a rotating magnetic field

US5237229A · kind A · utility

39Cited by
5References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 16, 1992
Grant dateAug 17, 1993
Priority date
Expiry dateApr 16, 2012

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16C32/0497
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The invention presents a novel magnetic bearing device of a simple design and construction, so that it can be attached to the ends of the driving shaft of a synchronous motor or a servomotor. The device consists of: a rotor having a number of permanent magnets, mounted on a central shaft where the central shaft is connected to a driving shaft of a rotating load of an external apparatus; and a stator surrounding the rotor with an airgap. The stator of the bearing device is provided with a number of electromagnets on the inner circumference which can be energized successively so as to create a rotating magnetic field constituted by opposing or attracting polarities to the field effect polarities created by the moving permanent magnets. An integration of the vertical force components over the inner circumference of the stator provides the total magnitude of the levitation force to support the external load. A theoretical analysis indicates that the levitation force is a constant when the number of poles of the rotating magnetic field is one more that of the PM magnetic field.

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