GB410352A - Improvements in and relating to electric discharge apparatus - Google Patents

Abstract

410,352. Discharge apparatus. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London.-(Assignees of White, W. C. ; 1053, Parkwood Boulevard, Schenectady, New York, U.S.A.) July 24, 1933, No. 20823. Convention date, July 23, 1932. [Class 39 (i).] In a tube having an electrode forming a part of the container, a casing is arranged to surround the glass base of the envelope including the seals and at least a part of the metal envelope to which it is secured in spaced relation, and is provided with a closed end except for an aperture through which cool air flows, past the glass to metal seal and out through the space between the envelope and the casing. In one form, Fig. 1, a copper or iron envelope 1 is provided with a handle 2 having holes 22 by means of which it may be bolted to a support, and is sealed to a glass base 3 having downwardly-extending tubes 11 to which are sealed metal thimbles 12. The electrode leads 10 are connected to the thimbles 12 and external connection is made by cables 13. A casing 16 surrounds the glass portion 3 and is spaced from the metal portion 1 by insulators 18. The casing 16 is closed at its lower end by a plate 19 of fibre with an aperture in which is mounted a fibre cylinder 21. The glass portion 3 has a central tube 15 in which mercury for the tube filling is placed. The cooling air entering at the cylinder 21 maintains the mercury vapour constant and flows as indicated by arrows, thereby cooling the seals. A forced draught may be produced if desired. When not in use the tube may stand upon the casing 16.