ELECTRIC LAMP WITH EXTERNAL METAL PLUG SEALING INLEAD TO PINCH SEAL

摘要

PHN. 9070. The invention relates to an electric lamp having a pinch seal in which a molybdenum foil is incorporated as a current leadthrough conductor. An external current conductor is connected to the foil. As a result of differences in coefficients of expansion, a capillary space is present around the external current conductor, through which space oxidizing gas can reach the molybdenum foil. Oxidation of the foil involves an increase of its volume and results in crack of the pinch seal. In lamps according to the invention a metal plug is provided around the external current conductor, said plug being sealed to said current conductor and to the glass of the pinch seal and sealing the capillary space in a vacuum-tight manner.