Single-phase brushless motor with cogging features
US4739203A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1986 |
| Grant date | Apr 19, 1988 |
| Priority date | — |
| Expiry date | Oct 24, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A single-phase brushless motor which can rotate smoothly by a uniform torque over an entire range of rotation with reduced torque ripples, without generating a high cogging torque for allowing self-starting of the motor. The motor comprises a field magnet as a rotor having 2P north and south magnetic poles, either the north or the south poles having a width equal to an electrical angle of about 120 degrees while the other poles have a width equal to an electrical of about 240 degrees. The field magnet is mounted for rotation in an opposing relationship to a stator armature core which has a plurality of radially extending stator poles formed in a circumferentially equidistantly spaced relationship thereon. A plurality of stator coils for two phases are wound selectively on the stator poles. An electric circuit detects the position of the field magnet to energize the armature coils for the two phases alternately for an electric angle of about 180 degrees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.