Abstract: The present invention discloses improved apparatuses for forming sheet glass. In one embodiment, the invention introduces a structural web that supports the forming structure in a manner such that the thermal creep which inevitably occurs has a minimum impact on the glass flow characteristics of the forming structure.

Abstract: The present invention discloses improved methods and apparatus for forming sheet glass. In one embodiment, the invention introduces a counteracting force to the stresses on the forming structure in a manner such that the thermal creep which inevitably occurs has a minimum impact on the glass flow characteristics of the forming structure.

Abstract: One embodiment of the present invention is an improved sheet glass forming apparatus. In another embodiment, a precise thermal control system redistributes the flow of molten glass at the weirs to counteract the degradation of the sheet forming apparatus which inevitably occurs during manufacturing. In yet another embodiment, the invention introduces a counteracting force to the stresses on the trough in a manner such that the thermal creep which inevitably occurs has a minimum impact on the glass flow characteristics of the forming trough. Another embodiment creates a variable external cross-section which provides hydraulic stresses that are in opposition to the surface tension and body force stresses and thus, reduces the influence of surface tension and body forces. In an alternative embodiment, the glass is preferentially cooled across its width to create forming stresses during solidification, which ensures that the glass sheet drawn is inherently flat.

Abstract: One embodiment of the present invention is an improved sheet glass forming apparatus. In another embodiment, a precise thermal control system redistributes the flow of molten glass at the weirs to counteract the degradation of the sheet forming apparatus which inevitably occurs during manufacturing. In yet another embodiment, the invention introduces a counteracting force to the stresses on the trough in a manner such that the thermal creep which inevitably occurs has a minimum impact on the glass flow characteristics of the forming trough. Another embodiment creates a variable external cross-section which provides hydraulic stresses that are in opposition to the surface tension and body force stresses and thus, reduces the influence of surface tension and body forces. In an alternative embodiment, the glass is preferentially cooled across its width to create forming stresses during solidification, which ensures that the glass sheet drawn is inherently flat.

Abstract: The present invention alters the flow path at the inlet of the sheet glass forming apparatus to improve quality. The bottom of the downcomer pipe is preferably shaped to alter the character of the vortex flow in the quiescent flow zone between the pipes. In another embodiment, a bead guide provides hydraulic stresses that are in opposition to the surface tension stress and thus reduces the influence of surface tension on the formation of thick beads on the edges of the sheet. The present invention also measures the temperature of the glass by immersing thermocouples in the glass, at locations where any defects caused by the immersion are in the glass that forms the unusable edges of the sheet. In another embodiment, the support structure for the trough is altered to substantially reduce the aging of the trough due to thermal creep.