Brushless motor
US6700279B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2002 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Mar 25, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention has a stator 3 around which an armature coil 11 is wound, a rotor 5 rotatably arranged inside or outside the stator 3, ring magnets 24 and a sensor unit 25 for detecting positions of the rotor, a motor driver 31 for controlling current flowing into the armature coil 11 such that a rotating magnetic field is formed in accordance with rotating positions of the rotator. The rotator 5 has a field magnet on including a plurality of permanent magnets 9 magnetized at the same pole, and a plurality of control poles 10 made of a magnetic material and arranged between the permanent magnets 9. Further, a field coil 13 forming a closed magnetic path passing through the control poles 10 is provided in a side of the stator 3. By controlling directions and amounts of current flowing into the field coil 13, motor characteristics are controlled without reducing motor efficiency thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.