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:
May. 11, 1993
Filed:
Apr. 11, 1991
Ulrich Pingel, Marl, DE;
Hans-Henning Nolte, Gelsenkirchen, DE;
Flachglas Aktiengesellschaft, Gelsenkirchen, DE;
Abstract
Process for contactless measurement of the electrical resistance (or of the electrical conductivity) of a preferably flat material (test material) in which an alternating current is capacitively coupled into the test material with the help of two coupling electrodes. The total impedance is measured at at least three different frequencies, and from that measurement, the stray capacitance between the two coupling electrodes, the coupling capacitance between the two coupling electrodes and the test material, as well as the resistance of the test material are determined. In a preferred embodiment the process is used for controlling the windshield wipers of a motor vehicle.