Method of Applying Amalgam-forming Metal in Low-Pressure Mercury Discharge Lamps

摘要

1,192,999. Metal-vapour lamps. PATENTTREUHAND-GES. FUR ELEKTRISCHE GL HLAMPEN m.b.H. 8 May, 1968 [11 May, 1967], No. 21820/68. Heading H1D. Amalgam-forming metal 11, e.g. In, is sprayed in the liquid state in finely divided form on to at least one electrode base 3 of a L.P.M.V. fluorescent lamp. The lamp envelope 1 is bent to U-shape (Fig. 2, not shown) after sealing. The metal 11 may become molten during lamp operation, but does not drip owing to the small quantity used. The coiled electrode 8 is surrounded by an annular shield 9 of sheet iron carrying a strip 10 of amalgam-forming metal, e.g. Sn, In or Pb, to facilitate starting. The main amalgam 11 determines the mercury vapour pressure during operation of the lamp.