| 摘要 |
523,923. Discharge lamps. GENERAL ELECTRIC CO., Ltd. (Patent - Treuhand - Ges. fur Elektrische Gluhlampen). Jan. 17, 1939, No. 1638. [Class 39 (i)] In high pressure metal vapour lamps having an envelope 2 of quartz, or other material having a thermal expansion co-efficient not greater than 1.5 x 10<SP>-6</SP> per ‹C., the main electrode 13 is surrounded by a sleeve 9 of quartz, and the lead to the auxiliary electrode 8 is on the outside of the sleeve. Preferably the auxiliary electrode is formed by turning the end of the lead over the edge of the sleeve. The main electrode consists of a coil of tungsten &c. on a core 12 of activating material, supported axially in the sleeve 9 and connected to the external lead 15 by an embedded strip 14. The lead 8 is connected to the external lead 17 by a strip 16, and the whole is sealed into the end 10 of the envelope. The envelope is supported in an outer bulb by leads passing through the foot tube and the auxiliary electrode is connected to one of the leads through a high resistance. |
