Process and apparatus for capacitive seat occupant sensing for motor vehicles

US9494629B2 · kind B2 · utility

Assignee

• I.G. BAUERHIN GMBH · DE

Inventors

• Axel Farr · Wächtersbach, DE
• Jochen Michelmann · Gelnhausen, DE

Key dates

• Filing date: Dec 18, 2013
• Grant date: Nov 15, 2016
• Expiry date: Jun 16, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03K2217/960745
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a method and an apparatus for capacitive seat-occupancy recognition for vehicle seats. The apparatus which is based on the method comprises a reference capacitor that possesses a capacitance with respect to a first reference potential of a vehicle, an electrode integrated into a seat sensor that possess a capacitance with respect to a first reference potential, an at least parasitically-present capacitance of the sensor electrode with respect to a second reference potential or the vehicle ground, a first switch that connects the reference capacitor and a reference-voltage source of known voltage connected with the reference potential, a second switch that connects the sensor electrode with reference capacitor, and a third switch that connects the sensor electrode with the reference potential and the at least parasitically-present capacitance with the vehicle ground.