The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 17, 2007
Filed:
Aug. 09, 2004
Joerg Schulz, Lustenau, AT;
Gerhard Heilig, Waldburg, DE;
Heidrun Richter, Wertingen, DE;
Bernd Steegmann, Heiligenhaus, DE;
Martin Witte, Ahaus, DE;
Gianni Uselli, Velbert, DE;
Joerg Schulz, Lustenau, AT;
Gerhard Heilig, Waldburg, DE;
Heidrun Richter, Wertingen, DE;
Bernd Steegmann, Heiligenhaus, DE;
Martin Witte, Ahaus, DE;
Gianni Uselli, Velbert, DE;
i f m electronic GmbH, Essen, DE;
Huf Huelsbeck & Fuerst GmbH & Co., KG, Veldbert, DE;
Abstract
A capacitive proximity switch for detecting the change in the capacitance relative to a setpoint capacitance by the approach or retreat of an object in the sensitive area of a proximity switch, especially for use in the door handle of a motor vehicle, provides reliable error detection and error suppression at a fundamentally high sensitivity of the capacitive proximity switch by utilizing an evaluation unit that evaluates a measured value of the change in capacitance over time and depending on the time behavior of the measured value activates changes the operating threshold from a first threshold (which can be caused by a false object coming into or out of the sensitive area of the proximity switch) to a higher second threshold which can be reached only at a relatively greater change in capacitance caused by a target object coming into or out of the sensitive area of the proximity switch.