Brushless D.C. motor
US4365187A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1980 |
| Grant date | Dec 21, 1982 |
| Priority date | — |
| Expiry date | May 15, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A D.C. brushless motor with a permanent magnet rotor employs Hall switches to effect commutation. The rotor magnets are of a greater axial length than the stator stack and the Hall switches are mounted on a printed circuit panel within the motor frame so as to be actuated by the fringe flux from the portion of a rotor magnet extending beyond the stator stack. The pole faces of the stator stack are stepped to assure proper starting and direction of rotation. A voltage regulating circuit forming part of the commutating arrangement on the printed circuit panel enables the same circuit to be used for a range of stator energizing voltages.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.