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:
Aug. 21, 2001
Filed:
Sep. 20, 1999
Hans Latarius, Essen, DE;
Tekmar GmbH, Essen, DE;
Abstract
A device for detecting snow and ice which has a humidity sensor and an ambient temperature sensor. An evaluator switch is controlled according to a humidity sensor-measured variable, producing a control signal at set humidity values for defrosting a surface which is being monitored for snow and ice. The ambient temperature sensor activates the humidity sensor within a temperature range of between +2° C. and −12° C. The humidity sensor itself has a PTC (positive temperature coefficient) heating element. The current consumption of the heating element is used as a measure of humidity. Both the ambient temperature sensor and the humidity sensor are positioned at a mutual distance in a longitudinally extended sensor cartridge made of plastic. The temperature sensor is thermally decoupled from the PTC heating element. The PTC heating element is built into a metal sleeve in such a way that it is corrosion and humidity proof.