Heatable vehicle window with different voltages in different heatable zones

• US 20030116551A1
• Filed: 09/07/2001
• Published: 06/26/2003
• Est. Priority Date: 09/07/2001
• Status: Active Grant

• Current Assignee: Guardian Europe S.A.R.L.. (Interguard Holding Corp.), Pharmexa A/S (Viktor Vladimirovich Kharitonin)
• Original Assignee: Centre Luxembourgeois de Recherches pour le Verre et la Ceramique SA
• Inventors: Sol, Jean-Marc, Lagrue, Herve
• Granted Patent: US 6,734,396 B2
• Time in Patent Office: Days
• US Class Current: 219/203
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10192 patterned in the form of columns or grids
• CPC Class Codes: B32B 17/10229 Metallic layers sandwiched by dielectric layers
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B60S 1/0848 Cleaning devices for cameras on vehicle
• CPC Class Codes: C03C 17/3639 Multilayers containing at least two functional metal layers
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: H05B 2203/008 with layout including a portion free of resistive material, e.g. communication window
• CPC Class Codes: H05B 2203/013 Heaters using resistive films or coatings
• CPC Class Codes: H05B 2203/016 Heaters using particular connecting means
• CPC Class Codes: H05B 3/84 Heating arrangements specially adapted for transparent or reflecting areas, e.g. for demisting or de-icing windows, mirrors or vehicle windshields
• CPC Class Codes: H05B 3/86 the heating conductors being embedded in the transparent or reflecting material H05B3/845 takes precedence

Abstract

A heatable vehicle window includes a bottom bus bar and a plurality of top bus bars. Voltages or electric potentials applied to the top bus bars are different, so that a first one of the top bus bars is at a given electric potential and another one of the top bus bars is at another electric potential (i.e., the voltages/potentials are offset from one another). The degree to which the top bus bar voltages/potentials are offset relative to one another is a function of the distance each respective bus bar is from the bottom bus bar across the heatable layer(s). Given a substantially continuous heatable layer(s), this can in certain example embodiments enable approximately uniform heating of the window (e.g., laminated vehicle windshield, laminated vehicle backlite, or laminated vehicle sidelite).

Claims

1. A heatable vehicle window comprising:

first and second substrates laminated to one another via at least one polymer inclusive interlayer;

a coating including at least one heatable conductive layer supported by said first substrate and extending across at least a portion of a viewing area of the window;

a bottom bus bar and first and second different top bus bars, each of said bottom and top bus bars being in electrical communication with said at least one heatable conductive layer; and

wherein first and second different voltages are applied to said heatable conductive layer via said first and second top bus bars, respectively, in order to heat said heatable conductive layer.

2. The heatable vehicle window of claim 1, wherein a distance d1 across said at least one heatable conductive layer between said bottom bus bar and said first top bus bar is greater than a distance d2 across said at least one heatable conductive layer between said bottom bus bar and said second top bus bar (i.e., d1>

d2), and wherein the first voltage applied via said first top bus bar is greater than the second voltage applied via the second top bus bar.

3. The heatable vehicle window of claim 2, wherein the first and second voltages are different in value as a function of a difference between distances d1 and d2.

4. The heatable vehicle window of claim 1, further comprising a third top bus bar in electrical communication with said at least one heatable conductive layer, and wherein a voltage is applied to the conductive layer via the third top bus bar that is different than the second voltage applied via the second top bus bar.

5. The heatable vehicle window of claim 4, wherein as viewed from a central portion of the bottom bus bar, the second top bus bar is at least partially between but vertically offset from the first and third top bus bars, and wherein the second bus bar is closer to the bottom bus bar across the heatable conductive layer than are the first and third top bus bars.

6. The heatable vehicle window of claim 4, wherein said coating is deleted to provide a toll device or rain sensor deletion area at an area behind the second top bus bar relative to the bottom bus bar, so that the second top bus bar is located between the deletion area and the bottom bus bar.

7. A heatable vehicle window comprising:

first and second substrates laminated to one another via at least one interlayer;

a coating including at least one heatable conductive layer supported by said first substrate,

a first bus bar located across said coating from a plurality of bus bars so that at least part of a viewing area of the window to be heated is located between at least part of the first bus bar and respective portions of the plurality of bus bars, each of said bus bars being in electrical communication with said at least one conductive layer of the coating; and

wherein first and second ones of said plurality of bus bars are used to simultaneously apply different voltages, respectively, across the at least one conductive layer in order to heat said at least one conductive layer.

8. The heatable vehicle window of claim 7, wherein said first bus bar comprises a bottom bus bar, and said first and second ones of said plurality of bus bars comprise top bus bars.

9. The heatable vehicle window of claim 7, wherein said first bus bar comprises a top bus bar, and said plurality of bus bars comprise bottom bus bars.

10. The heatable vehicle window of claim 7, wherein a distance d1 across said at least one conductive layer between said first bus bar and said first one of said plurality of bus bars is greater than a distance d2 across said at least one conductive layer between said first bus bar and said second one of said plurality of bus bars, and wherein the voltage applied to the conductive layer via said first one of said plurality of bus bars is greater than the voltage applied via the second one of the plurality of bus bars.

11. The heatable vehicle window of claim 10, wherein the different voltages applied via the different ones of the plurality of bus bars are different in value as a function of a difference between distances d1 and d2.

12. The heatable vehicle window of claim 7, wherein a first heating zone is defined by said conductive layer between said first bus bar and said first one of said plurality of bus bars, and a second heating zone is defined by said conductive layer between said first bus bar and said second one of said plurality of bus bars, and wherein said first and second heating zones have approximately the same specific power when said first and second voltages are being applied across the conductive layer.

13. The heatable vehicle window of claim 12, wherein said conductive layer is continuous across said first and second heating zones.

14. A method of heating a vehicle window including first and second substrates laminated to one another via at least one interlayer, with at least one heatable conductive layer supported by said first substrate, the method comprising:

applying different voltages across said conductive layer via first and second different bus bars in order to heat at least part of the vehicle window.

15. The method claim 14, wherein said first and second bus bars are both top bus bars, and wherein said first and second different voltages are applied across a viewing area of the window simultaneously.

16. A vehicle window comprising:

a conductive layer supported by a substrate;

wherein a first voltage V1 is applied across the conductive layer via first and second bus bars, and a second voltage V2 is applied across the conductive layer via said first bus bar and a third bus bar; and

wherein the second bus bar is spaced further across said conductive layer from said first bus bar than is said third bus bar, and wherein V1>

V2.

17. The vehicle window of claim 16, wherein the first and second voltages V1 and V2 are selected in accordance with equation of d2/d1=V2/V1, where d1 is a distance across the conductive layer between the first and second bus bars, and d2 is a distance across the conductive layer between the first and third bus bars.