초록 ▼

A temperature control device for a heatable windshield which includes a temperature sensitive resistance member that extends into critical areas of the windshield to monitor the windshield temperature and prevent overheating. The voltage drop across the member is compared to a set voltage drop value

A temperature control device for a heatable windshield which includes a temperature sensitive resistance member that extends into critical areas of the windshield to monitor the windshield temperature and prevent overheating. The voltage drop across the member is compared to a set voltage drop value as the windshield is powered and becomes heated. When the member\s voltage drop exceeds the set value, the power to the heatable windshield is automatically interrupted to prevent overheating.

대표청구항 ▼

In an electrically heatable transparent article including a dielectric substrate, an electroconductive coating on a surface of said substrate, and first and second spaced apart bus bars along opposing edge portions of said coating to pass a current from one of said bus bars through said coating to t

In an electrically heatable transparent article including a dielectric substrate, an electroconductive coating on a surface of said substrate, and first and second spaced apart bus bars along opposing edge portions of said coating to pass a current from one of said bus bars through said coating to the other said bus bars, wherein current flow from said one of said bus bars through said coating to said other of said bus bars results in a selected portion of said coating having a higher temperature than the remaining portions of said coating, the improvement comprising: an electrically conductive member for sensing temperature changes wherein resistance of said member varies as the temperature of said selected portion of said coating varies; said member positioned within said transparent article and electrically insulated from said coating and in close proximity to said selected portion of said coating to sense temperature variations in said selected portions wherein resistance output of said member indicates the temperature of said selected portions of said coating.