Method for producing electrically conductive heated glass panels

#The present invention generally relates to electrically conductive heated glass panel assemblies and control systems, for warming objects and for the removal of moisture on such glass panel assemblies. More particularly, the present invention relates to regulating the flow of current in low emissivity (low E) conductive metal oxide coatings on insulated glass (IG) panels and laminated structures. Most particularly, the present invention deals with the electrical connectivity to insulated glass panels, laminated structures, and combinations thereof.

#At the present time, heating, cooking, moisture control, and the electrical control of such processes and activities do not take full advantage of the potential of the use of coated glass. In general, utilizing thin-film coatings to produce heat in a glass panel is an established concept. However, in the past, the film deposition techniques, such as those used in spray coating, were not precise, which resulted in non-uniform coatings and consequently imprecise heating. Recently, the depositing of the coatings has improved, for example, through the use of chemical vapor deposition (CVD), but the electrical control of and connectivity to the coatings has not.

#An application of heated glass that has seen these changes over the last thirty years is, for example, the commercial refrigerator and freezer doors in supermarkets, where a tin oxide coating is disposed on one of the interior surfaces of an IG panel and where an electric current is dissipated in the tin oxide to provide heat to raise the glass temperature above the dew point. On such doors, the heat eliminates the formation of condensation, so that employees and customers can view the refrigerator/freezer contents after individuals have opened and closed the doors.

#FIG. 1a is a schematic of an overview of an integrated connection circuit in accordance with the present invention;

#FIG. 1b is a schematic of an interconnection of an electrically conductive heated glass panel and a first glazing channel in accordance with the present invention;

#FIG. 1c is a schematic of an interconnection of an electrically conductive heated glass panel and a second glazing channel in accordance with the present invention;

#The present invention employs an integrated connection circuit 18, as shown in FIG. 1a, where electrical current (I) passes through a coating that is disposed on a sheet of a dielectric material, for example, an electrically conductive heated glass panel 20, to generate heat that can be used for warming, cooking, moisture control, and the like. The panel 20 may be realized within the present invention as a laminated panel 40, an insulated glass panel 30, or a combination thereof. The present invention has been found to apply to sheets that are dielectric substrate materials other than glass, for example, ceramic and glass-ceramic materials.

#In order to control the electrical current (I) flowing through the electrically conductive heated glass panel 20, a solid-state controller 16, for example, a programmable application-specific integrated circuit. (ASIC) chip, would monitor inputs like a signal (S) from a condition-sensing means, for example, a condition sensor 21. Examples of conditions that could be sensed by the condition sensor 21 include, but are not limited to, temperature, moisture, voltage, and current. Also, the signal (S) may be obtained from voltages taken across the bus bars 22. If those voltage signals (S) are taken rapidly by way of the controller 16 the voltages can be converted into an indication of the temperature of the panel 20.

#Another way the present invention may obtain a signal (S) is through the placement of a thermostatic switch (not shown) on a major surface 33 of the panel 20, wherein if the temperature of the surface 33 reaches a first setpoint, the thermostatic switch is electrically conductive and if the surface temperature reaches a second setpoint the thermostatic switch is electrically nonconductive.