Sensor arrangement for detecting changes in angle

US6205866A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Thomas Ullmann · Arnstadt, DE
• Anton Dukart · Gerlingen, DE
• Klaus Marx · Stuttgart, DE
• Franz Jost · Stuttgart, DE
• Hans-Juergen Herderich · Weingarten, DE

Key dates

• Filing date: Jul 22, 1999
• Grant date: Mar 27, 2001
• Expiry date: Jul 22, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B7/24
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The sensor device accurately measures small angle changes of mechanical parts that rotate relative to each other. The sensor device includes only one cylindrical magnet (3) extending axially from a first part; two magnetoresistive sensors (5',5") mounted on a second part and located in the magnetic field of the sole magnet (3), the two magnetoresistive sensors having respective magnetic field sensitive layers (MS) facing a magnetic pole of the magnet (3), extending tangentially to a rotation direction in which the parts rotate relative to each other and generating respective output signals according to magnetic field line direction; and a device (PT) for combining the respective output signals of the two magnetoresistive sensors (5',5") to produce a combined output signal characteristic of the relative rotation angle of the parts. The combined output signal is set to zero when the parts are at a predetermined relative rotation angle.