GB720179A - Improvements in or relating to gaseous electric discharge tubes - Google Patents

Abstract

720,179. Multi-gap cold-cathode tubes. INTERNATIONAL BUSINESS MACHINES CORPORATION. Oct. 11, 1951 [Oct. 26, 1950]. No. 23688/51. Class 39 (1). [Also in Group XIX]. In a gaseous discharge tube of the glow transfer type, the position of the glow discharge on a given electrode, which may be an anode or a cathode, is determined solely by the surface materials of that electrode. Thus, if a number of plane cathodes each having one part made of nickel and another part made of carbon are arranged opposite a common anode, a discharge between any cathode and the anode will concentrate at the nickel part of the cathode since this part has the lower work function. In the tube shown the cathodes are in the form of hollow cylinders coated on the inside with nickel and on the outside with carbon so that the glow discharge is confined to the inside of each cathode. Ten storage position cathodes CP-0 to CP-9 and ten glow transfer cathodes CO-0 to CO-9 are separated by insulating plates I and arranged in a circle equi-distant from a common ring anode A which is formed in two sections to prevent overheating when processing and may be arranged in line with the longitudinal axes of the cathodes or offset therefrom. Glow transfer wires TP-0 to TP-9 and TO-0 to TO-9 are each attached to a cathode and extend either around the edge of an insulating plate I or through a perforation in the plate to the region of intense ionization adjacent the open end of a neighbouring cathode, to determine the direction of transfer of the glow discharge along the array of cathodes. The tube is connected in a circuit (see Group XIX) whereby starting cathode CP-0 is connected individually and storage cathodes CP-1 to CP-9 are connected in common to a source of positive voltage while transfer cathodes CO-0 to CO-9 are connected in common to the anode of a triode tube which is biased to cut-off so that when positive pulses are applied to the grid of this tube the voltage applied to the transfer cathodes is varied alternately above and below that applied to the storage cathodes and the glow discharge is stepped along the array of cathodes to the storage cathode corresponding in number to the number of pulses applied to the grid of the valve. The tenth pulse returns the glow discharge to the starting cathode CP-0 and an output is obtained. Alternatively, by providing an individual connection to each position cathode CP-1 to CP-9 an output can be obtained for each pulse applied to the tube. Specifications 708,114 and 708,119 are referred to.