GB281400A - Improvements in or relating to vacuum electric tube devices - Google Patents

Abstract

281,400. Robinson, E. Y., Hubbard, E. J. E., and Metropolitan-Vickers Electrical Co., Ltd. Sept. 3, 1926. Vacuum tubes. - An electrode structure in which all the electrodes are supported by wires secured in a foot, has an anode surrounding a rectilinear cathode except for an opening which is equidistant from the cathode throughout its length, and a tubular grid supported by a wire or rod mounted in the opening in the anode and extending along its length. The arrangement facilitates the escape of heat, from the cathode. As shown, a U-shaped anode 18 is formed by two plates fitting around a rod 2 which is sealed into the foot 3 and has heatradiating fins 4, 5. The fins 5 are tied by wires 6. The loop of a hairpin filament is supported by a plate spring 16 welded to a wire 17, which is secured to a glass bead 18 supported from the rod 2. The grid consists of a flattened helix of wire welded around a support wire 8 as described in Specification 231,225. The wire 8 is mounted in the opening of the anode and is spaced from the rod 2 by a glass bead 12 and wires; it may act as a space current confining shield in the manner described in Specification 195,691. In a modification an equipotential cathode of the kind described in Specification 278,787 may be used, the grid being of circular section. According to the Provisional Specification the electrodes may be duplicated, and the cathodes connected in series or parallel or independently. Specification 273,394 also is referred to.