Magnetic sensor system with initialization mechanism
US12235135B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 2022 |
| Grant date | Feb 25, 2025 |
| Priority date | — |
| Expiry date | Mar 9, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D2205/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present disclosure provides magnetic sensor system that includes a magnet mounted on the end of a rotating shaft, a magnetic sensing device comprising a magnetic multi-turn sensor, and a mechanism for initializing the magnetic multi-turn sensor into a known state ready for use. Whilst the magnetic sensing device is being used to monitor the rotation of the shaft, the magnet is located in a starting position a first distance from the magnet sensing device such that the magnet field strength experienced by the magnet sensing device is within the operating window of the magnet multi-turn sensor, the operating window being defined by a minimum magnetic flux density, Bmin, and a maximum magnetic flux density, Bmax. The mechanism comprises a means for moving the magnet and the shaft in an axial direction towards the magnet sensing device such that the magnetic field experienced by the magnet sensing device exceeds the upper limit, Bmax, of the operating window. This causes domain wall nucleation, whereby the sensor spiral is filled with domain walls that magnetise all of the magnetoresistive elements into the same state. Once the initialization has taken place, the mechanism is confi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.