Ppg Industries, Inc.

Jeffrey L Marietti

Rudolph A Karlo

George R Claassen

David B Rayburn

Irvin A Wilson

John L McLaughlin

Robert G Frank

Samuel E Behanna

The present invention discloses a method and apparatus for shaping glass sheets to deeply sagged configurations using a lower outline mold and an upper shaping mold while minimizing marking of the sheets by shaping molds. The outline mold includes a support rail which generally corresponds to the desired curvature of a peripheral portion of the sheets to be shaped and supports the glass sheets as they are heated and sagged by gravity to a preliminary shape. The outline mold and the upper mold are then moved relative to each other to position the molds either in close proximity to each other or to press the upper mold against the glass sheets. Pressurized gas is then directed from the mold to at least the unsupported central portions of the preliminarily shaped sheets, to urge these unsupported portions downward and shape the sheets to a desired configuration.

Pressure forming of glass sheets

The present invention discloses a method for shaping glass sheets to deeply sagged configurations using a lower outline mold and an upper shaping mold while minimizing marking of the sheets by shaping molds. The outline mold includes a support rail which generally corresponding to the desired curvature of a peripheral portion of the sheets to be shaped and supports the glass sheets as they are heated and sagged by gravity to a preliminary shape. The outline mold and the upper mold are then moved relative to each other to position the molds either in close proximity to each other or to press the upper mold against the glass sheets. Pressurized gas is then directed from the mold to at least the unsupported central portions of the preliminarily shaped sheets, to urge these unsupported portions downward and shape the sheets to a desired configuration.

A flexible shaping ring for shaping heat softened glass sheets lifts a heat softened glass sheet and presses it against the shaping surface of an upper mold. As the shaping ring presses the marginal edge portion of the sheet against the upper mold, its shaping surface deforms to generally conform to a corresponding portion of the upper mold. A press ring subsequently contacts the shaping ring and presses it against the upper mold to further shape the marginal edge portion of the glass sheet and ensure the marginal edge completely conforms to the shape of the upper mold.

Growing community of inventors

Tarentum, PA, United States of America

Jeffrey L Marietti