GB154991A - Improvements in and relating to incandescent lamps and similar articles - Google Patents

Abstract

154,991. British Thomson - Houston Co., (General Electric Co.). Sept. 4, 1919. Forming electric-lamp bulbs and the like.-In making miniature lamps or other electrical apparatus, the leading-in wires are allowed to rest on the bulb neck, to which an exhaust tube is then sealed; a cool refractory rod is then introduced to maintain or form a passage through the tube and the joint is compressed. Fig. 1 is an elevation and Fig. 2 a side elevation of a machine for carrying out the operation. The bulb 7 is held by suction in an exhausted cup 6 on the tube 5 passing through a pulley 4. The exhaust tube 19 is supported in a spring clamp 18 secured to a standard 17 on the pulley. The refractory rod 31 is supported by a spring 33 resting on an arm 30 secured to a cap 24 which slides on the standard 17 and is supported by a spring 23. The cap 24 is connected by links 25, 26 with pressure jaws 27, 28. After fusion, the cap 24 is depressed until the screw 34 engages the top of the standard 17, thereby effecting introduction of the rod 31 and partial closure of the jaws 27, 28. The .tube 5 may be adjusted in height by a link 8 and rack 10 operated by a hand-wheel 13. The rod 31 is preferably of tungsten, but may be of other metal or of carbon or other non-metal. The bulb may be sealed just above the compressed portion of the neck, no special contraction in the exhaust tube being necessary.