System and method for detecting an axial position of a shaft
US7280937B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 2006 |
| Grant date | Oct 9, 2007 |
| Priority date | — |
| Expiry date | Apr 18, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D2205/77
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A shaft comprises a hardened outer metallic layer having a first hardness level with a generally uniform radial depth. A first strip extends in a generally longitudinal direction in the outer metallic layer. The first strip has a second hardness level different from the first hardness level. A second strip in the outer metallic layer has the second hardness level. The first strip and the second strip are spaced apart from each other over at least a longitudinal region. A sensor senses an angular difference between a first magnetic field associated with the first strip and a second magnetic field associated with the second strip. A data processor references an established relationship between a position of the shaft and the angular difference between magnetic fields associated with the first strip and the second strip to detect a position of the shaft with respect to a reference point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.