Capacitive seat occupancy detection system operable at wet conditions

US10131249B2 · kind B2 · utility

Assignee

• IEE INTERNATIONAL ELECTRONICS & ENGINEERING S.A. · LU

Inventors

• Guenter Goedert · Trier, DE
• Oleg ZEILER · Igel, DE
• Edmund N. Marx, Jr. · Speicher, DE
• Ingrid Scheckenbach · Ferschweiler, DE

Key dates

• Filing date: Feb 1, 2016
• Grant date: Nov 20, 2018
• Expiry date: Feb 1, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03K2217/960765
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A vehicle seat occupancy detection system includes at least one capacitive sensor member having at least one sensing electrode, an impedance measurement circuit for determining a complex impedance or a complex admittance of the at least one sensing electrode, an evaluation unit for generating an output signal based on a determined complex admittance of the at least one sensing electrode and comparison of the determined complex admittance to at least one predetermined value, and at least one electrically conductive ground connecting member that is intentionally electrically connected to the reference electrode and that is arranged in close proximity to the at least one sensing electrode. The at least one ground connecting member and the at least one sensing electrode are galvanically separated such that, when the seat gets wet, the sensing electrode is directly electrically connected to the reference electrode by the at least one ground connecting member.