GB462788A - Electron discharge devices - Google Patents

Abstract

462,788. Thermionic valves. STANDARD TELEPHONES & CABLES, Ltd. April 9, 1936, No. 10549. Convention date, April 27, 1935. [Class 39 (i)] A long anode 15 consists of two parallel plates with flanges 17 at their ends welded together and with stiffening flanges 16 along the edges of the plates; housed within this anode are a number of grids 25 arranged side by side and within each grid is a filamentary cathode 31. Surrounding the anode are insulating side plates 22, 23 fixed in end mica discs 20, 21, which are supported on the anode ends, the upper disc having a serrated circumference to bear on the envelope interior. The grids are supported on rods 26 fixed in the side plates and are connected together electrically, by short pieces 27. The filaments are supported (i) by hooks 32 from the plate 23 (ii) by hooks 33 connected to upright rods 34, 35 outside the plate 22 and to the filament ends and (iii) by spring fingers 40, 41, Fig. 5, engaging bights in the filaments and fixed to clips 42 crimped on to the edge of the plate 22. The filaments are in parallel, the rods 34, 35 forming connectors to the base terminals 14. The whole of the electrode structure is supported from the pinch by a stiff rod 18 welded to the lower flanges 17 on the anode, the rod 18 also acting as anode lead. Indirectly heated cathodes may be used instead of filamentary.