GB430915A - Improvements in or relating to electric discharge rectifiers and the like - Google Patents

Abstract

430,915. Discharge devices. AKT.- GES. BROWN, BOVERI, & CIE, Baden, Switzerland. Dec. 27, 1933, No. 36342. Convention date, Dec. 24, 1932. [Class 39 (i)] In a gas- or vapourfilled discharge device such as a rectifier or an inverter, provided with a thermionic cathode or a cathode upon which an incandescent spot is formed, the discharge is extinguished by means of a negative potential applied to a grid which is located from the anode at a distance equal to the mean free path of an electron, and is so constructed that the sum of the areas of all the apertures, uniformly distributed over the grid, is equal to less than one-third of the area of those surfaces of the grid on the side thereof remote from the cathode. An anode A is secured to an insulator J which supports a grid G through a cap K. The grid is provided with apertures o and with supplementary deionizing members S which consist of round or angular pins or flat bars. In a modification, the anode is provided with ribs R located between the members S, which need not be mechanically secured to the grid, and may be connected thereto directly or through a resistance, or may be connected permanently or periodically by means of a contact maker, to a negative potential at which the current reaches saturation value. An exciter grid may be located between the control grid and the cathode and is permanently connected to the corresponding anode through a resistance.