Magnetoresistive angular position sensor and rotation speed sensor

US5796249A · kind A · utility

Assignees

• Institut fuer Physikalische Hochtechnologie E.V. · DE
• HL-Planar Technik GmbH · DE

Inventors

• Wulf Andra · Wetzlar, DE
• Roland Mattheis · Jena, DE

Key dates

• Filing date: Oct 30, 1996
• Grant date: Aug 18, 1998
• Expiry date: Oct 30, 2016

Classification

• Technology area (CPC G): Physics
• CPC primary: G01P3/487
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A sensor for sensing at least one of angular position and rotation speed comprises a permanent magnet rotatable about an axis of rotation and at least three Wheatstone bridges each having four bridge resistors formed of magnetoresistive strip lines extending in planes parallel to a rotation plane of the permanent magnet. The bridge resistors of each of the at least three Wheatstone bridges are disposed on respective sides of quadrangles corresponding to respective ones of the at least three Wheatstone bridges. Each of the at least three Wheatstone bridges has two adjacently arranged ones of the bridge resistors connected to a half-bridge of respective ones of the at least three Wheatstone bridges. The quadrangles are disposed relative to one another rotated by a preselectable angle .alpha.. The at least three Wheatstone bridges each have an intersection point of virtual diagonals connecting corners of respective ones of the quadrangles, the intersection points being arranged substantially concentrically about the axis of rotation, and the at least three Wheatstone bridges are disposed so as to be equally and evenly swept by a field of the permanent magnet during rotation thereof to…