Method and apparatus for delivering a coated glass stream for forming charges of glass

摘要

A method and apparatus for delivering a coated glass stream having a first inner layer and a second outer layer wherein the method comprises providing a vertical orifice (20;100,102), delivering molten glass from a first source (22) through the orifice, providing a gap (G) about the orifice intermediate its upper and lower ends, delivering glass from a second source (24) about the gap such that the glass from the second source flows through the gap to provide an outer layer about the glass from said first source as it flows through the orifice, and controlling the size (L) and shape of the gap parallel to the flow and the size (G) of the gap perpendicular to the flow such that the gap provides sufficient flow resistance and the gap is of sufficient size and shape to prevent clogging. The method includes the step of providing passages (65) for the flow of the glass from the second source (24) and controlling the size and shape of the passages such that the passages are sufficiently large to minimize flow resistance therein and to provide sufficient pressure to force the glass through the gap and provide less resistance than the metering gap. The method also includes providing a plurality of orifices (100,102), each having a gap, delivering glass from the first source (22) through each of the orifices, delivering glass from the second source (24) to the gaps and controlling the size and shapes of such gaps.