GB352440A - Improvement in electron tube - Google Patents

Abstract

352,440. Thermionic valves. FEDERAL TELEGRAPH CO., Hobart Building, San Francisco, U.S.A.-(Assignees of Litton, C. V. ; Redwood City, California, U.S.A.) Jan. 6, 1930. No. 501. Convention date, Jan. 5, 1929. Void [Published under Sect. 91 of the Acts]. [Class 39 (i).] In a valve having an anode disposed so as not to intercept all the electrons from the cathode, means are provided for preventing bombardment of the envelope by stray electrons. As shown in Figs. 1 and 3, a hollow, liquid-cooled, semi-cylindrical anode 12 is arranged on one side of a hairpin cathode 11, and electrons passing by the vertical edges 41 of the anode are intercepted by members 42 of metal which conduct away heat due to bombardment, or of insulating material such as glass or quartz which assume a negative potential and serve also to repel electrons. A grid, curved to the shape of the anode, consists of vertical rods 24 secured by horizontal bars 26 and supported from collars 28. The members 42 may consist of tubes through which cooling air or water is circulated or of a U-shaped tube, the arms of which may be between the cathode and the edges of the anode. The grid may extend beyond the edges of the anode, the bars in the extensions being closer together than elsewhere so as to assist the interception of electrons. In other arrangements the intercepting members act as cooling supports for the grid. For example, the grid may consist of curved, horizontal rods, connected with a U-shaped intercepting member, or of horizontal tubes connected with vertical interceptor tubes whereby cooling air may be circulated through the grid. In another arrangement, Fig. 13, (not shown) intercepting members of insulating material are secured to the edges of the anodes. As shown in Fig 19, the anode 812 and grid 23 are flat, the edges of the anode being curved so as to make the intercepting members 842 more effective. A curved plate interceptor of metal or quartz may be interposed between the cathode and the envelope. In the arrangement shown in Fig. 24, an interceptor plate 62, mounted on the support 14 for the cathode 11, extends beyond the side edges and also beyond the upper and lower edges of a semi-cylindrical anode 12, and is slotted to form grid bars 64.