Process for bending glass to a relatively sharp angle

Claim 2

A process for bending a glass sheet as claimed in claim 2, wherein said sheet is heated to a temperature in the range of from 900* to 1,150* F. prior to passing said electrical current along said path, and said area immediately adjacent said path is heated to from 1,200* to 1,350* F. when said current is passed along said path.

Claim 3

A process for bending a glass sheet to a relatively sharp angle, comprising applying a layer of electrically conducting material to at least one surface of a flat sheet of glass to be bent, which layer extends continuously along a substantially straight line from one edge of the sheet to the opposite edge thereof, supporting the flat sheet along its marginal edge portions only above a shaping surface of a bending mold, heating the sheet to a temperature above the strain point of the glass but below the bending temperature thereof, applying an electrical potential across said line of a sufficient magnitude and for a time adequate to raise the temperature of the glass in the area immediately adjacent said line to its bending temperature, and bending said sheet by gravity along said line into conformity with the shaping surface of the mold.

Claim 4

A process for bending a glass sheet as claimed in claim 4, wherein said electrically conducting layer is produced by stenciling an electrically conducting metal and frit containing paste on the glass surface and thereafter firing said paste to fuse the metal to the glass.

Claim 5

A process for bending a pair of glass sheets to a relatively sharp angle, comprising applying a layer of electrically conducting material to at least one surface of each of two similarlY sized and shaped flat glass sheets to be bent to form paths which extend continuously along substantially straight lines from one edge of each sheet to the opposite edge thereof, superimposing one of said sheets upon the other such that said electrically conducting paths lie in the same vertical plane, heating the assembled sheets to an elevated temperature but below the bending temperature of the glass, applying an electrical potential across each of said paths of sufficient magnitude and for a time adequate to heat each sheet in the area immediately adjacent said paths to a temperature above the bending temperature of the glass, and bending said sheets along said paths to form said relatively sharp angle therein.

Claim 6

A process for bending a pair of glass sheets to a relatively sharp angle, comprising applying a layer of electrically conducting material to one surface of each of two similarly sized and shaped flat glass sheets to be bent to form paths which extend continuously along a substantially straight line from one edge of each sheet to the opposite edge thereof, superimposing one of said sheets upon the other such that said electrically conducting paths lie in the same vertical plane with said one surface of each being the outwardly disposed surfaces of the assembly, supporting the assembly along its marginal edge portions only above a shaping surface of a generally horizontally disposed bending mold, heating the assembled sheets to a temperature above the strain point of the glass but below the bending temperature thereof, passing an electrical current through both of said electrically conducting paths of a sufficient magnitude and for a time adequate to raise the temperature of the area immediately adjacent thereto on both sheets to the bending temperature of the glass, and bending said sheets along said paths into conformity with said shaping surface of the mold to form a generally V-shaped structure.

Claim 7

A process as defined in claim 7, wherein said electrically conducting paths are produced by stenciling an electrically conducting metal and frit containing paste on the glass surface and thereafter firing said paste to fuse the metal to the glass.

Claim 8

A process for bending a glass sheet to a relatively sharp angle, comprising applying an electrically conducting metal containing glass frit suspension in a thin path to at least one surface of a flat glass sheet to be bent, which path extends continuously along a substantially straight line from one edge of the sheet to the opposite edge thereof, supporting the flat sheet along a portion of its marginal edge only above a shaping surface of a bending mold, heating the sheet to a temperature above the strain point of the glass but below the bending temperature thereof to fuse the metal glass frit suspension to the glass, applying an electrical potential across the fused path of a sufficient magnitude and for a time adequate to raise the temperature of the glass sheet in the area immediately adjacent said path to its bending temperature, and bending said sheet along said path into conformity with the shaping surface of the mold.

Claim 9

A process for bending a glass sheet as defined in claim 9, wherein said suspension is applied to said sheet by a silk screen process and said sheet is heated to a temperature in the range of from 900* F. to 1,150* F. to fuse said metal glass frit suspension to the sheet.