Magnet assembly and a voice coil motor using such magnet assembly
US5329267A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 1993 |
| Grant date | Jul 12, 1994 |
| Priority date | — |
| Expiry date | Mar 11, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K41/0358
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Magnet assemblies for installation into a voice coil motor is described. A pair of magnetic pieces are molded into circular arc shapes of different radii and positioned concentrically across a gap. The ends of such the pair of magnet pieces, are joined to a similarly-molded other pair of magnet pieces. The direction of magnetization of the former pair of magnet pieces is reverse that of latter pair of a magnet pieces. On the upper curved surface of each of the two units of lower magnet pieces of smaller radius, a cut plane, for example, is formed in order to provide unbalanced cubic volume between one half and the other half from the center plane of a magnet piece, thus increasing the gap magnetic flux density being generated inside the gap at the sections of larger cubic volume, thereby improving overall evenness of the gap magnetic flux density distribution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.