Brushless motor with center leads for preventing signal distortion
US4737675A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 4, 1986 |
| Grant date | Apr 12, 1988 |
| Priority date | — |
| Expiry date | Aug 4, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a brushless motor, a rotor magnet comprises a main magnetizing member with alternate N-poles and S-poles and a subsidiary magnetizing member for detecting rotational speed disposed at an inner side and having N-poles and S-poles arranged at a smaller pitch in comparison to the main magnetizing member. A stationary plate is provided with stator coils opposed to the main magnetizing member and a detecting substrate has a pattern in opposition to the subsidiary magnetizing member for detecting rotational speed. The detecting substrate is installed on the stator coils, and leads from the detecting substrate extend through the center of the stationary plate towards the rear side thereof, to avoid the signal distortion of prior art designs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.