Low profile ring-shaped motor
US4731554A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1985 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Nov 14, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K21/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A low profile ring-shaped motor has a housing, a bearing support attached to the housing and supporting a rotating shaft carrying a ring-shaped rotor. A ring-shaped stator is secured to the housing and is concentric and between the legs of the U-shaped rotor. The stator is formed by a continuous strip of magnetic material wound and laminated in a toroid and having helical windings therearound. On the inside of the legs of the rotor are mounted a plurality of permanent magnets forming the poles of the motor. Radially opposite magnets are of the same polarity. Control of the switching of the current through the windings is by means of Hall Effect devices sensing the change in polarity of a ring shaped magnet means having the same number of poles as does the permanent magnets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.