GB836918A - Gaseous-discharge tube - Google Patents

Abstract

836,918. Thermionic valves. EDGERTON GERMESHAUSEN & GRIER Inc. May 9, 1957 [July 24, 1956], No. 14796/57. Class 39(1). [Also in Group XI] A gas-filled discharge tube having an envelope composed in part of insulating material (e.g. ceramic) and in part by a re-entrant cupshaped first electrode sealed to said insulating material, has a further cup-shaped electrode, inverted with respect to the first electrode and of greater depth than same, and supported by a flanged lip sealed through the envelope ; the two electrodes have their base portions in close proximity. Fig. 1 shows a hydrogenfilled thyratron, in which the first electrode is a copper anode 9 having a lower suface 17 of molybdenum. The further electrode is the control electrode 37, centred in the envelope by dimples 24, and having one or more apertures 41 in its upper surface 39. Anode and control electrode are both sealed to the ceramic envelope by the seal described in Specification 836,919. Instead of passing directly through the envelope wall, as at 43, electrode 37 may have an interposed insulating member, Fig. 2 (not shown), The cathode 21 is supported on hollow pins 23 extending through the ceramic base of the tube, and a baffle may be provided in the discharge path between electrodes 21 and 39. Some typical dimensions and operational data are given. U.S.A. Specifications 2,518,879 and 2,592,556 also are referred to