Permanent magnet arrangement
US5320103A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1991 |
| Grant date | Jun 14, 1994 |
| Priority date | — |
| Expiry date | Oct 15, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F7/0278
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A permanent magnet assembly used for creating a uniform magnetic field across a portion of an air gap has a permanent magnet grouping, including a first, principal magnet, a pole piece contacting said principal magnet, and a set of auxiliary magnets extending about the periphery of the pole piece. Two such magnet groupings are positioned within a test chamber, separated a spacer, with the magnet groupings and the chamber defining the air gap across which the magnetic field extends. The strength and uniformity of the magnetic field is adjusted by including a second set of auxiliary permanent magnets or a set of electromagnetic shim coils positioned within the air gap surrounding and overtapping a portion of the air gap. Further adjustment of the magnetic field is accomplished shaping the front surfaces of the pole pieces, thus affecting the shape and direction of the resulting magnetic field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.