Brushless DC motors/generators
US5751089A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1994 |
| Grant date | May 12, 1998 |
| Priority date | — |
| Expiry date | Sep 28, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K2201/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a rotational/linear brushless DC motor/generator the rotor/slide has many equally spaced permanent magnet poles of alternating polarity and it has no or few magnetically permeable iron parts. These magnets cover typically slightly more than half the pole pitch in trapezoidal embodiments. The stator consists of one or several pairs of two stator parts facing each other. Each stator part has a plurality of poles with the same pitch as the rotor/slide poles. The stator parts in a pair are arranged on each side of the rotor/slide and are displaced 180 electrical degrees from each other. Each one of the two stator parts in a pair has windings for one phase in order to polarize the poles in the stator part in alternating polarity. The gaps between the stator poles facing the rotor/slide in the same stator part are small compared to the pole pitch. In this way high torque/force DC motors/generators with low weight and high efficiency are provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.