Homogeneous field magnet having pole shoes with pole piece means which are spaced over a correction air gap
US5363078A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 1994 |
| Grant date | Nov 8, 1994 |
| Priority date | — |
| Expiry date | Mar 9, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/383
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The magnet contains a magnetic yoke and two pole shoes between which a magnetic field of high homogeneity is formed. The pole shoes are provided with special pole piece device. Each pole piece device is spaced from a base part facing the yoke by a narrow correction air gap. In accordance with the invention, each pole piece device contains two plate-like pole piece elements which are parallel to each other and spaced apart by a gap of predetermined width. In this connection, the plate element facing the base part has a relative permeability (.mu..sub.r 1) which is smaller by at least a factor of 5 than the plate element facing the useful volume, the relative permeability (.mu..sub.r 2) of which element is at least 10,000.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.