GB191501694A - Improvements in Ionization Devices for Amplifying Electric Currents. - Google Patents

Abstract

1694. Western Electric Co., [Western Electric Co.]. Feb. 3. Vacuum tubes.-In a tube of the " audion " type for use as a relay, the hot cathode and primary electrode are separated by a space only just sufficient to insulate them. A large amplifying ratio is thus obtained. As shown in Fig. 1, the hot cathode may be a #-shaped filament 2, and the primary electrode a grid 1. For high-pressure secondary currents, the grid is of small mesh and is at a considerable distance from the secondary electrode plate 3; but when the secondary pressure is less than the primary pressure, the grid is of larger mesh and all the electrodes are close together. The cathode and primary electrode may be in one plane between parallel secondary plates. In this case the primary may consist either of two oblong plates, between the edges of which the cathode fllament is placed, or of parallel wires with interposed cathode filaments. The cathode filament may be wound on to the primary electrode, which is coated with nickelous oxide or other insulating-material, and may consist of a # or #-shaped wire, a plate notched at its edges, or a helically grooved cylinder within a co-axial cylinder forming the secondary electrode. This last form may be adapted for cooling by placing the cylindrical electrodes in contact with inner and outer tubes 9, 8, Fig. 12, fused together at their ends with the inner tube open. The container thus formed may be immersed at an inclination in water or may be cooled internally by water circulation and externally by air. The conductor 13 to one end of the hot cathode traverses a glass tube fitted in an external groove in the secondary electrode.