Ppg Industries, Inc.

James J. Finley

Amy M. Roginski

Charles Richard Coleman

Terry L. Wolfe

Frank Howard Gillery

Pamela L. Martino

Thomas M. Carter

Russell C. Criss

John A. Winter

Terry L Wolfe

Charles R Coleman

John A Winter

Stephen J Schultz

James J Finley

Russell C Criss

Frank H Gillery

Thomas M Carter

Richard E Wilhelm

Amy M Roginski

Pamela L Martino

Randall S Johnson

Elizabeth A Fiano

William D Reader

An electrically heatable windshield with a hidden bus bar configuration. A border of opaque ceramic material, preferably a lead borosilicate enamel, is bonded to an interior surface of the transparency about its periphery. Opposing electroconductive bus bars, preferably a low frit content silver-containing ceramic material, are bonded to the ceramic material so that the entire inner edge of the bus bar overlays a portion of the ceramic material and is spaced from the inner edge of the border, providing an intermediate portion of the border between the bus bars and transparency surface that is not covered by the bus bars. An electro-conductive coating is applied to the transparency to interconnect the bus bars and covers to the inner surface of the transparency, the bus bars and the intermediate portion of the ceramic material border so that electric current flowing between the bus bars must flow through the portion of the coating that covers the intermediate portion of the border.

Electrically heatable transparency

Thermal energy from quartz lamp heaters are used to fire ceramic enamel material onto a glass substrate while minimizing any increase in the temperature of the glass.

Processing glass sheets with ceramic enamel bands

A heat softened glass sheet is conveyed directly from a heating furnace onto an advancing conveyor belt which is supported on a scissor table. The glass sheet is advanced on the belt to a position below an upper press face. The scissor table increases the sag of the belt and the corresponding curved configuration of the supported glass sheet as it lifts the glass sheet into pressing engagement with the upper press face. During pressing, the glass sheet and belt generally conform to the shaping surface of the press face.

Belt assisted press bending

This invention relates to shaping glass sheets by roll forming to either simple or complex curvatures about a single axis of bending or to compound curvatures comprising components of curvature about mutually perpendicular axes of bending by a controlled, repeatable program of roll forming without causing the glass sheets to stop their forward movement during their shaping. The apparatus used to perform this process has a minimum of moving parts, thus minimizing maintenance problems and reducing downtime for maintenance and repair.

Method and apparatus for shaping moving glass sheets by sagging followed

A conveyor roll for conveying glass sheets and a conveyor comprising a plurality of said conveyor rolls is described. Each conveyor roll comprises a curved shaft conforming to the shape of said glass sheets transverse to their path of movement, a plurality of hubs of essentially cylindrical configuration mounted around said curved shaft and having loosely interfitting tongues and grooves and a cylindrically shaped collar of a material that does not mar glass in tightly fitting relation about each of said hubs. When torque is applied to one of the end hubs of said conveyor rolls, the glass engaging surfaces of said collars rotate in unison at a uniform peripheral speed to convey the curved glass sheets through a cooling area included in glass sheet tempering apparatus with minimum scuff marks because the different collar surfaces rotate at the same rotational speed against the engaged surfaces of said curved glass sheets.

Apparatus for conveying glass sheets

Applying a boron nitride composition to a flexible fiber glass fabric cover for a press bending mold for shaping heat-softened glass sheets having a portion painted with a composition consisting essentially of a finely divided frit-pigment mixture by impregnating at least the portion of the cover that engages the painted portion of the glass sheet reduces the likelihood of marking the press bent glass sheet in unwanted regions. In addition, such impregnation facilitates removing the press bending molds from the press bent glass sheet when the press bending molds are separated after engaging the heat-softened glass sheet.

Treating covers for press bending molds, and method of press bending

Heat-softened glass sheets are shaped to either simple or compound bends while being continuously conveyed by means of forming rolls having transverse curvature, wherein, in at least the first portion of the bending station, the force of gravity alone causes the glass sheets to sag into substantial conformity with the transverse curvature of the forming rolls. Support for each glass sheet is gradually transferred from straight conveyor rolls to curved forming rolls without vertically reciprocating the rolls. Optionally, at the exit end of the forming station, a set of upper forming rolls having transverse curvature complementary to that of the lower forming rolls may be provided to assure close conformance to the desired curvature. Compound bends may be formed by providing the path defined by the lower forming rolls with a concave curvature in the direction of glass travel.

Method and apparatus for shaping glass sheets by roll forming

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Allison Park, PA, United States of America

Terry L Wolfe