Ironless, brushless DC motor with wave-winding
US4618806A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 11, 1985 |
| Grant date | Oct 21, 1986 |
| Priority date | — |
| Expiry date | Feb 11, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A simplified fan and brushless DC motor has a rotor with an annular permanent magnet that is magnetized in segments about its circumference and is associated with a wave-wound stator coil. Alternate circumferential segments of the magnet are oppositely polarized. Fan blades are located within the annular magnet. The wave-winding varies in position to present alternate magnetic fields opposite in direction to the rotor magnet outer surface to cause rotation thereof. The stator is ironless. The coil can have two bifilar windings alternately energized. A Hall device is, typically, employed for commutation along with suitable switching circuitry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.