| 摘要 |
472,194. Discharge apparatus. GENERAL ELECTRIC CO., Ltd. (Patent- Treuhand-Ges. f³r Elektrische Gl³hlampen) July 27, 1936, No. 20745. [Class 39 (i)] For starting purposes a discharge device, in which one or both main electrodes are thermionic and are heated by the discharge only, comprises an auxiliary electrode 11 in the neighbourhood of one main electrode 5 and connected to the other main electrode 6 through a resistance 13 so small that-the auxiliary discharge heats the main electrode, and another electrode 14 which is located half-way along the discharge path, is connected to a main electrode 6 through a resistance 18 greater than the resistance 13 and is adapted to co-operate with another conductor 19 to initiate an auxiliary discharge. The resistances 13, 18 may be constituted wholly or partly by discharge gaps, or they may be arranged within the discharge envelope and suitably shielded, or they may consist of conducting layers on any of the glass surfaces. Supplementary high-frequency starting means may be used. The U-shaped envelope 1 is filled with rare gas and sodium and is housed within an envelope 2 fitted with a mantle 4 and a cap 3. The main electrodes consist of tungsten spirals which enclose rods of alkaline earth compound and are each provided with two leads so that they may be heated during manufacture. The electrodes 14, 19 are housed in glass tubes which are supported by the envelope through springs 21 and have resistances which prevent short-circuiting of the discharge. |
