Thermomagnetic encoding method and articles
US5492571A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1993 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Oct 25, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49007
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An article comprising first and second bodies of permanent magnet material, each of said first and second bodies consisting substantially of a substrate of permanent magnet material being magnetized substantially uniformly to a predetermined flux density in a range from zero flux to 100% flux saturation of the permanent magnet material; each of the first and second bodies also comprising a pattern of at least one affected volume in a surface of the body, wherein each affected volume has a magnetic flux density that varies from the substantially uniform predetermined flux density and wherein the first and second bodies are stacked and fixedly attached so that the pattern on each body aligns with the pattern on the other body, wherein at least one affected volume on the first body is aligned with at least one affected volume on the second body and wherein the aligned affected volumes comprise a pole detectable by a magnetic sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.