Magnetic rotational position sensor with improved output linearity
US5444369A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 18, 1993 |
| Grant date | Aug 22, 1995 |
| Priority date | — |
| Expiry date | Feb 18, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P3/487
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rotary shaft position sensor includes a stator and a rotor and produces a linear output signal in accordance with the rotational position of a shaft coupled to the rotor. The rotor rotates about an axis of rotation. The stator includes stationary pole pieces having stationary pole faces situated perpendicular to the axis of rotation and spaced a predetermined distance apart to define an air gap therebetween. A Hall effect device is situated-in the air gap. The Hall device produces an output signal corresponding to the level of magnetic flux in the air gap. One or more magnets are attached to the rotating pole piece. The magnetic poles of the magnets are situated parallel with and spaced a predetermined distance from the stationary pole faces. Lines of magnetic flux originating from the magnets are situated in a direction perpendicular to the stationary pole face. The rotating pole piece rotates in close proximity to the stationary pole pieces. As the rotor rotates about the axis of rotation, a portion of the magnet is aligned with the stationary pole faces. Magnetic flux corresponding to the aligned portion of the magnet and the stator pole faces appears in the air gap. A tempera…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.