Improvements in or relating to vacuum-tight seals for electrical apparatus

摘要

578,580. Metal-to-glass seals. PATELHOLD PATENTVERWERTIUNGS- & ELEKTROHOLDING AKT.-GES. March 8, 1945, No. 5822. Convention date, April 4, 1944. [Class 36] [Also in Group XXIII] Porous glass, for use in the production of metal-to-glass seals for lamps, electron-tubes, highvoltage condensers, and other fluidtight devices, consists mainly of spheroidal glass grains the dimensional ratio of the largest to smallest of the individual grains being not greater than 2, and their absolute dimensions being not greater than 0.35 mm. and not less than 0.1 mm. ; and, the actual porosity being not greater than 5 per cent. of the mass. As illustrated, the granular glass 3 may be sintered under pressure in a two-part graphite mould 1, 2 having apertures 5 for the assembly. of conductors 4.