| 摘要 |
1,217,654. Electric incandescent lamp. PATENT-TREUHAND-GES. FUR ELEKTRISCHE GLUHLAMPEN m.b.H. 15 April, 1969 [26 April, 1968; 21 Nov., 1968], No. 19280/69. Heading H1F. In manufacturing an incandescent electric lamp, a halogenated hydrocarbon is added to the fill gas and the mixture thermally decomposed, prior to introduction into the lamp envelope, by local heating of the feed conduit of the lamp. A fill gas comprising argon or nitrogen with dibromoethane is introduced through exhaust tube 13 through a tungsten section 14 packed with tungsten chips or grit 15 and heated by an auxiliary filament 16 which is designed to glow and burn out below the operating voltage of the main filament. Decomposition of the dibromoethane gives a mixture of bromine or hydrogen bromide and the carbon produced may be deposited on a baffle within the envelope. In another embodiment (Fig. 3, not shown) the hydrocarbon is decomposed on a bare tungsten filament (16a) which receives the carbon produced. The auxiliary filament may be bifilar wound. In an alternative embodiment (Fig. 1, not shown), the mixture of inert gas and dibromoethane is introduced through an exhaust tube heated by gas burners, the tube collecting the deposited carbon. In this case the lamp is tipped off between the envelope and the deposited carbon. The mixture of fill gas and halogen or hydrogen halides may not necessarily be introduced straight into the envelope but by way of an intermediate tank. |
