Electrically heated panel with anti-shock conductive strips
First Claim
1. In an anti-fogging, heated windowpane of the type including a sheet of transparent glass having a pair of generally opposing, planar surfaces, a peripheral edge having a plurality of edge portions, and an electrically conductive, transparent coating applied to a portion of one of said surfaces, the improvement comprising the combination of an uncoated, insulating space extending around the entirety of said one surface of said sheet between the edge of said coating and said peripheral edge;
- a first elongated strip of electrically conductive material applied to said sheet within said uncoated, insulating space, said first strip having a beginning end located adjacent one portion of saiD peripheral edge of said sheet and extending around and being insulated from substantially all of the total length of the edge of said coating after which said strip includes a contact portion which extends into electrical contact with a predetermined length of a first portion of said edge of said coating;
a second, elongated strip of electrically conductive material applied to said sheet in electric contact with a predetermined length of a second portion of said edge of said coating;
said second portion of said coating edge and said second, elongated strip of electrically conductive material being spaced across said coating a predetermined distance apart from and in general opposition to said first portion of said coating edge and said contact portion of said first strip;
electrical conduction means for conducting electricity to said first strip and for grounding said second strip, said conduction means engaging said first strip at said beginning end, whereby an electrical current transmitted from said first strip across said coating to said second strip for heating said coating and said sheet is automatically shut off upon fracture of said sheet anywhere along its length which causes a severance of said first strip along its length.
1 Assignment
0 Petitions
Accused Products
Abstract
An anti-fogging, electrically heated, frangible panel or windowpane especially adapted to prevent electrical shocks to persons who might come in contact therewith after fracture or breakage. The pane includes an uncoated, insulating, marginal band which extends completely around a transparent, electrically conductive coating. An electric current conductive strip is adhered in the marginal band and extends substantially completely around the coating before contacting an edge thereof. Fracture or breakage of any portion of the windowpane severs the conductive strip at some point around the periphery of the pane preventing current flow through the coating.
32 Citations
16 Claims
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1. In an anti-fogging, heated windowpane of the type including a sheet of transparent glass having a pair of generally opposing, planar surfaces, a peripheral edge having a plurality of edge portions, and an electrically conductive, transparent coating applied to a portion of one of said surfaces, the improvement comprising the combination of an uncoated, insulating space extending around the entirety of said one surface of said sheet between the edge of said coating and said peripheral edge;
- a first elongated strip of electrically conductive material applied to said sheet within said uncoated, insulating space, said first strip having a beginning end located adjacent one portion of saiD peripheral edge of said sheet and extending around and being insulated from substantially all of the total length of the edge of said coating after which said strip includes a contact portion which extends into electrical contact with a predetermined length of a first portion of said edge of said coating;
a second, elongated strip of electrically conductive material applied to said sheet in electric contact with a predetermined length of a second portion of said edge of said coating;
said second portion of said coating edge and said second, elongated strip of electrically conductive material being spaced across said coating a predetermined distance apart from and in general opposition to said first portion of said coating edge and said contact portion of said first strip;
electrical conduction means for conducting electricity to said first strip and for grounding said second strip, said conduction means engaging said first strip at said beginning end, whereby an electrical current transmitted from said first strip across said coating to said second strip for heating said coating and said sheet is automatically shut off upon fracture of said sheet anywhere along its length which causes a severance of said first strip along its length.
- a first elongated strip of electrically conductive material applied to said sheet within said uncoated, insulating space, said first strip having a beginning end located adjacent one portion of saiD peripheral edge of said sheet and extending around and being insulated from substantially all of the total length of the edge of said coating after which said strip includes a contact portion which extends into electrical contact with a predetermined length of a first portion of said edge of said coating;
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2. The improvement of claim 1 wherein said sheet is rectangular;
- said coating being rectangular with said coating edges extending parallel to said peripheral edges of said sheet and spaced back therefrom to define said insulated space, the edges of said coating including two sets of parallel, opposing edges, the edges in each of said sets being perpendicular to those of the other set;
said first strip extending around three entire edges of said coating and substantially all of the fourth edge from said beginning end location in said insulating space to a position immediately adjacent said beginning end location, said contact portion of said first strip extending into electrical contact with the entirety of one of said coating edges in one of said sets from said position immediately adjacent said beginning end location;
said second strip extending in electrical contact with the entirety of the remaining edge of said coating in said one set of edges.
- said coating being rectangular with said coating edges extending parallel to said peripheral edges of said sheet and spaced back therefrom to define said insulated space, the edges of said coating including two sets of parallel, opposing edges, the edges in each of said sets being perpendicular to those of the other set;
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3. The improvement of claim 2 wherein said contact portion of said first strip is parallel to, spaced from, and substantially coextensive with the portion of said first strip extending along said fourth edge of said coating.
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4. The improvement of claim 1 wherein said first strip is positioned generally midway between said coating edges and said sheet peripheral edges in said insulated space except for said contact portion thereof which extends out of said insulated space into electrical contact with said first portion of said edge of said coating.
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5. The improvement of claim 1 wherein said first and second strips comprise silver paste applied to said sheet in the desired locations, said sheet with said paste being heated to bond the paste to the sheet.
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6. The improvement of claim 5 wherein said sheet of glass is annealed glass prior to deposition of said silver paste thereon, the heating of said sheet and paste causing said annealed glass to become partially tempered and strengthened.
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7. The improvement of claim 1 wherein said windowpane further comprises partially tempered and strengthened glass.
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8. An anti-fogging, electrically heated, panel comprising the combination of a sheet of frangible material and electric current conduction means for preventing the occurrence of electrical shocks upon breakage of the panel;
- said current conduction means including a layer of electrically conductive material applied to a portion of at least one surface of said sheet and defining a marginal, uncoated, insulating, electrically nonconductive band extending around the entirety of said sheet between the edge of said layer and the peripheral edges of said sheet, at least one elongated strip of electric current conducting material applied to said sheet within said marginal band and extending alOng said band substantially completely around said layer from a first portion to a second position immediately adjacent said first position, said one strip including a contact portion extending from said second position into electrical contact with a predetermined length of one portion of said edge of said layer, another elongated strip or electric current conducting material applied to said sheet in electrical contact with a predetermined length of another portion of said edge of said layer, said other elongated strip and other portion of said layer edge spaced a predetermined distance across said layer and generally opposing said one portion of said layer edge and said contact portion of said one strip, and electrical contact means for supplying electric current to said one strip at said first position and for grounding said other strip whereby current flow from said contact portion of said one strip across said layer to said other strip for heating said panel is automatically stopped upon fracture of said sheet causing severance of at least one portion of said one strip along its length between said first and second positions.
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9. The panel of claim 8 wherein said one strip has a predetermined uniform width dimension along its length;
- said second position being spaced from said first position a distance no greater than said width dimension.
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10. The panel of claim 9 wherein the portions of said one strip except for said contact portion are spaced from the edge of said layer a distance at least as great as said width dimension of said strip.
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11. The panel of claim 9 wherein said electric current conducting strips are silver paste applied to said uncoated, marginal band of said sheet, said sheet and strips being heated to bond said strips to said sheet.
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12. The panel of claim 11 wherein said sheet is a sheet of annealed glass prior to deposition of said silver paste thereon, the heating of said sheet and paste causing said annealed glass to become partially tempered and strengthened.
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13. The panel of claim 8 wherein said panel further comprises partially tempered and strengthened glass.
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14. The panel of claim 8 wherein said contact portion of said one strip is parallel to but spaced from another portion of said one strip.
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15. The panel of claim 8 wherein said layer is rectangular, said generally opposing portions of said layer edge contacted by said contact portion of said one strip and said other strip including a pair of the edges of said rectangle which are parallel to and opposite one another.
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16. The panel of claim 15 wherein said one strip extends around three entire edges and substantially all of the fourth edge of said layer rectangle, said contact portion of said one strip extending generally coextensively with, parallel to but spaced from a second portion of said one strip, said second portion of said one strip extending along said fourth edge of said layer rectangle within said marginal band adjacent said fourth edge.
Specification