Magnetically coded device
US5631093A · kind A · utility
145Cited by
6References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 8, 1991 |
| Grant date | May 20, 1997 |
| Priority date | — |
| Expiry date | Nov 8, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12465
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Nonmagnetized permanent magnet material is heated in a pattern by a laser beam to a localized temperature above the Curie point or a temperature sufficient to reduce the coercivity sufficiently for an external field to magnetize the pattern in the direction of the field. Magnets so produced can have very high pole density, digital encoding and analog patterns having gradually varying local field strength. Alternating pole magnets of this type can be used for stepper motor magnets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.