Inductive linear position sensor including exciting and receiving coils and a movable induction coupling element

US6483295B2 · kind B2 · utility

Assignee

• Hella KGaA Hueck & Co. · DE

Inventors

• Henning Irle · Lippstadt, DE
• Norbert Kost · Geseke, DE
• Franz Schmidt · Mannheim, DE

Key dates

• Filing date: May 25, 2001
• Grant date: Nov 19, 2002
• Expiry date: May 25, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/204
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An inductive linear position sensor, particularly for use with motor vehicles has an oscillator circuit for creating a periodic alternating voltage signal, an exciting coil coupled to the oscillator circuit, a plurality of receiving coils with the exciting and receiving coils being structured as leads on a circuit board, evaluation circuitry for evaluating signals induced in the receiving coils and a movable inductive coupling element for influencing the strength of inductive coupling between the exciting coil and the receiving coils. The evaluation circuitry is arranged within the geometry of at least one of the sending (exciting) and receiving coils. Effective surface areas of the receiving coils are structured at beginning and end areas of the sensor such that, when there is no movable element present, a zero voltage results at the output taps of the receiving coils. The structure of the sensor compensates for offset voltages, which are created by asymmetrical positions of the receiving coils to the exciting coil as well as for components of the evaluation circuitry.