High intensity radial field magnetic array and actuator
US6828890B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2002 |
| Grant date | Dec 7, 2004 |
| Priority date | — |
| Expiry date | Nov 2, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F7/066
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A miniature actuator, e.g., for use in a Micro Air Vehicle, comprises at least one nested array of magnets, with an outer annular magnet with a magnetization pointing in an axial direction, a middle annular magnet with a radial magnetization, and an inner cylindrical magnet with a magnetization directed anti-parallel to the magnetization of the outer annular magnet. In one embodiment, a permanent magnet actuator comprises such an array, and a conductive coil having a current distributed over the volume of the conductive coil, wherein the magnetic field of the array is perpendicular to the current located in the coil. The coil may be located above or below the first magnetic array. In another embodiment, a conductive coil is disposed between two magnetic arrays. The coil may have a winding that is pancake-shaped, solenoidal, or toroidal and may comprise more than one winding. The magnetic arrays may be canted to permit the toroidal winding to expand, affording control over the spread of the magnetic field in the gap.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.