Improvements in or relating to electric discharge tubes and other hermetically sealed devices incorporating glass to metal seals

摘要

792,299. Glass-metal seals. ENGLISH ELECTRIC VALVE CO., Ltd. July 13, 1956 [Oct. 10, 1955], No. 28787/55. Class 36. The glass portion of a glass-metal seal consists of fragmentized glass, the fragments of which have been softened and coalesced into a vacuum-tight body. Glass tubing is initially heated to its softening point and then shattered by plunging into cold water. Fragments up to SP1/SP/ 4 inch maximum dimension are loaded into carbon moulds containing the metal parts and the moulds heated to about 900‹ C. to soften and coalesce the glass.