GB426092A - Improvements in electric discharge lamps - Google Patents

Abstract

426,092. Discharge lamps. GENERAL ELECTRIC CO., Ltd., Magnet House, Kingsway, London, JENKINS, H. G., and RYDE, J. W., c /o General Electric Co., Wembley, Middlesex. Feb. 23, 1934, No. 5997. Addition to 349,261. [Class 39 (i)] In a discharge lamp provided with means for introducing a continuous stream of impurity to vary the form, position or intensity of the discharge as described in the parent Specification, the said means consists of a solid so placed in the main body of the lamp that its vapour has substantially free access to the discharge space. Anthracene 6, Fig. 1, is distilled into a space in the lamp, bounded by a cylindrical iron electrode 2 and mica discs 8, 9, from a side tube 5 and a constriction 7 is then sealed. Leading-in wires 4 pass through the disc 8, and strips 11 of the electrode are bent to form supports for the disc 9 which is notched at its edges for the passage of the vapour. The temperature of the anthracene, during operation, may be adjusted by suitably positioning it within the lamps, e.g. in ripple tubes filled with neon, the constriction 7 is nearer the disc 9, and the disc 8 is replaced by an annular disc which is nearer the disc 9, and in ripple tubes filled with mercury and argon the disc 9 and the constriction 7 are near the pinch or the screen 9 may be abolished and the constrcition placed between the pinch and the disc 8. In another form, the material is located between the wall of the lamp and a tube which is provided with a constriction 16, is sealed to the wall at 14, and is shaped to provide an annular passage 15 for the vapour. The temperature of the material may be further adjusted by means of lagging on the tube. The filling may consist of neon at 10 to 40 mm. or of argon at 5 mm., and mercury. In a further form, the anthracene may be housed within an open glass container arranged loosely in the lamp and retained near an electrode by a constriction in the lamp.