Improvements in or relating to multiple glass-to-metal seals for electron discharge devices

摘要

696,987. Glass-to-metal seals. SHEPHERD, G. R. (Westinghouse Electric International Co.). Oct. 5, 1951, No. 23231/51. Class 36. A multi-seal envelope 11 for an electron discharge device is made by preparing a plurality of annular metal discs 13 for the application of vitreous material thereto, assembling a plurality of hollow vitreous envelope sections 12 alternately with the discs 13, vitreous material 15, having a lower softening temperature than the sections 12 and a coefficient of expansion matching that of the discs 13, being placed therebetween, then heating the assembly to soften the vitreous material 15 but not the sections 12, cooling to cause the vitreous material to seal the parts together simultaneously, and finally annealing the completed envelope. The members 13 may be prepared by pre-oxidization, sand-blasting or etching, and may be enamelled by firing on a layer 14 of powder glass, after which the welding glass 15 is applied and the coated discs assembled for sealing with the sections 12. The welding glass may be applied directly to the metal discs, and may be fired to form an enamel coating before the sealing process.