GB501376A - Improvements in or relating to sealed vessels for electric discharge devices - Google Patents

Abstract

501,376. Uniting metal to vitreous and ceramic material by heat. BERRY, R. J. (Lorenz Akt.-Ges., C.) Oct. 22, 1937, No. 28868. [Class 36] [Also in Group XL] A vacuum vessel comprises a glass envelope 3, Fig. 4, with a ceramic or metal cover 4 which is sealed by a melt 5 to an annular intermediate member 1 made of hard glass or ceramic material, or a mixture of glass and ceramic materials, this intermediate member being united with the glass envelope. In the example. the cover 4 serves as a receptacle for a glass melt 5. Radial lugs 14 within the intermediate member 1 provide a mounting for electrode supports 10 which are connected to leading-in wires 9 in the cap by wires 16 embedded in the melt 5. The glass envelope 3 overlaps and is sealed around the upper edge of the member 1. Fig. 6 shows a modification wherein a ceramic intermediate member 1 sealed to a glass envelope 3 is secured by a covering melt 5 to a metal cover consisting of an annular part 30 and stem 4. The melt consists of a glass material which is placed on the metal cover and heated by high-frequency currents induced therein. The melt also seals leading- in wires 16 passing through apertures 34 in the stem 4. In a further modification the intermediate member is located within the flared lower end of a glass discharge vessel and is flush with the opening thereof which is sealed within a glass melt in a dished cover. Radial arms within the intermediate member provide supports for leading-in wires which are fixed thereon by solder or hard glass. The coefficient of expansion of the intermediate member is preferably of a value intermediate those of the envelope and cover. The melt may consist of a glass containing molybdenum oxide or other molybdenum compound.