| 摘要 |
433,437. Discharge apparatus. GENERAL ELECTRIC CO., Ltd., Magnet House, Kingsway, London.-(Assignees of Patent-Treuhand- Ges. f³r Elektrische Gl³hlampen; 11, Ehrenbergstrasse, Berlin) April 1, 1935, No. 10087. Convention date, April 7, 1934. [Class 39 (i)] In a discharge tube having thermionic main electrodes, the heating element 2 of each electrode is connected at one end to the supply and at the other end to a surrounding metal sheath 8. An auxiliary electrode 17 formed as a second sheath surrounding the first is connected through an insulated helical conductor 13 within the tube to an electrode similarly arranged at the other end (not shown), neither electrode being connected to the main electrodes. Initially, a discharge starts between the members 8, 17, and the auxiliary discharge current passing through the heaters 2 raises them to electron emitting temperature and initiates the main discharge. Springs 16 engaging the wall of the tube support the insulated conductor 13. The sheaths 8, 17 act as heat shields for the thermionic electrodes which may comprise heaters coated with emissive material, or enclosed in metal cylinders, or enclosing rods 3 of alkaline carths. Specification 410,558 is referred to. |
