GB482318A - Improvements in or relating to the sealing of electric conductors through quartz or hard glass - Google Patents

Abstract

482,318. Sealing leading-in conductors into quartz envelopes. GENERAL ELECTRIC CO., Ltd. (Patent-Treuhand-Ges. f³r Elektrische. Gl³hlampen) Nov. 6, 1936, No. 30274. [Class 36] [Also in Group XL] In making a seal between an envelope 1 of quartz, or other very hard glass, and one or more electric conductors of oxidizable metal which attain a high temperature during the operation of the device and are introduced into the envelope through an elongated vitreous sealing tube 7, the central portion of the tube 7 is expanded to form a chamber the walls of which are spaced from the part 9 of the leading- in.conductor, and the chamber is filled with neutral gas or evacuated. The parts 6, 10 of the leading-in conductor in contact with the vitreous material consist of thin molybdenum strips which are sealed therein in known manner, their inner ends being connected by the part 9 which lies within the chamber 8 and consists of thicker strip. The inner ends of the strips 6 are connected to tungsten electrode-supporting wires, and the outer ends of the strips 10 to tungsten or molybdenum leads 11. The upper electrode is surrounded by a quartz hood 12 to prevent the deposition of sputtered material upon the envelope wall. In order to conserve heat a silvered coating 14 provided on the upper part of the envelope. Two leading- in conductors may be carried side by side through the same sealing tube 7 and chamber 8 and either connected to the same electrode or different electrodes. Specifications 207,590 and 211,862, [both in Class 39 (ii)], are referred to.