Sensing device for detecting the angular displacement and relative position of a member of magnetic material
US5982171A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 1996 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | Nov 1, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/147
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensing device capable of outputting a correct signal precisely corresponding to a particular position (angle) of, for example a protruding or recessed portion of a rotating member made of a magnetic material as soon as the electric power of the sensing device is turned on. The sensing device includes: a magnet for generating a magnetic field; a rotary member of magnetic material for changing the magnetic field generated by the magnet, the rotary member being disposed at a predetermined distance apart from the magnet; a giant magnetoresistance device which changes in resistance in response to the magnetic field whose magnitude is changed by the rotary member of magnetic material; and a differential amplifier for detecting the displacement of said rotary member of magnetic material and also the relative position of said rotary member of magnetic material with respect to said giant magnetoresistance device when said rotary member of magnetic material is at rest, on the basis of the output signal of said giant magnetoresistance device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.