GB1388957A - Process and apparatus for use in manufacturing sheet glass - Google Patents

Abstract

1388957 Drawing sheet glass GLAVERBEL 5 July 1972 [20 Aug 1971 (2)] 31483/72 Heading C1M In a process of manufacturing sheet glass by upward drawing through a drawing chamber, gas displacing forces are exerted in the drawing chamber to cause gas circulation therein. The gas displacing forces may be provided by ejectors which eject preheated gas into the drawing chamber. In one arrangement (Figs. 1 and 2), an ejector 25 is mounted on one side of the ribbon adjacent the edge thereof while a second ejector 26 is mounted opposite the ejector 25 but downwardly displaced therefrom. In a second arrangement (Figs. 3 and 4), two pairs of vertically spaced ejectors 48, 50 are mounted adjacent one edge of the ribbon 27 on one side thereof while a second pair of ejectors 47, 49 is mounted adjacent the other ribbon edge directly opposite the first pair. The upper two ejectors 47, 48 point in one direction while the lower two ejectors 49, 50 point in the other direction across the ribbon 27. In a third arrangement (Figs. 6 and 7), a series of ejectors 81, 83, 85, 87 is provided adjacent one edge of the ribbon and a corresponding series of ejectors 82, 84, 86 provided adjacent the other ribbon edge directly opposite the first series. A control device 89 operates so that gas is ejected from diagonally opposite pairs of ejectors, e.g. 82, 83, while adjacent ejectors 81, 84 are inoperative and vice versa. In a further arrangement (Fig. 5), two opposite pairs of vertically spaced ejectors 48, 50 and 47, 49 are provided inclined to the horizontal and are operated in a similar fashion to the ejectors illustrated in Fig. 7. The gas displacing forces may also be provided by mechanical means, e.g. propellers. The drawing chamber may be associated with a vertical annealing shaft 10 (Fig. 1), or a horizontal annealing shaft 76 (Fig. 6), in which case a bending roller 74 is utilized. The drawing chamber is provided with a pair of main coolers 20, 21 and a pair of secondary coolers 23, 24. The gas displacing devices may be arranged so that one such device is adjacent each cooler. The molten glass may be conveyed to the drawing chamber on a body of molten material. Specifications 1,388,956 and 1,388,958 are referred to.