| 摘要 |
1398324 Drawing sheet glass GLAVERBEL 5 July 1972 [13 Aug 1971 29 Aug 1971] 31482/72 Heading C1M In a process for drawing sheet glass by upward drawing through a drawing chamber, which is supplied by causing a continuous flow of molten glass into the drawing chamber, a mixing action is imposed on the gases above the molten glass outside the drawing chamber by exerting gas displacement forces in a direction across the flow of molten glass. The mixing action preferably takes place at a position between the drawing chamber and a shut off which isolates the drawing apparatus from an associated glass melting furnace. The mixing action may take place in a region between the drawing chamber and an end wall of the kiln containing the molten glass. The mixing action may be achieved by directing gas from one or more Gifford or Venturi type ejectors located in the side walls of the kiln in which the molten glass is held. In one arrangement (Figs. 1 and 2) two pairs of ejectors 19, 20 and 21, 22 are provided on each side wall, one ejector of each pair being horizontally displaced from the other. Gas is supplied first two diagonally opposite ejectors such as 19, 27 and then the other two diagonally opposite ejectors 20, 22 while gas supply to the ejectors 19, 21 is shut off and so on altenately, thus encouraging circulation of gases. Alternatively gas may be supplied alternately to the pairs of ejectors on each side wall. In a further arrangement (Fig. 7) the pair of ejectors 89, 87 are displaced horizontally from an opposite pair of ejectors 86, 88. Also shown on Fig. 7 are ejectors 84, 85 mounted on angled conduits so that by rotating the conduits about their axes the position of the ejectors 84, 85 may be adjusted independently. Gas may also be directed into the kiln from conduits 106-109 (Fig. 8) the outlets of which are closable by means of vanes 110-113 and through screens of flames provided by burners 101-104. The mixing action may further be achieved by using mechanical means such as propellers (Fig. 8, not shown). |
