GB861361A - Improvements relating to the capping of electric lamps - Google Patents

Abstract

861,361. Incandescent electric lamps. A.E.I. LAMP & LIGHTING CO. Ltd. Oct. 5, 1959 [Oct. 16, 1958], No. 33079/58. Class 39 (2). In order to ensure that the filament of an incandescent lamp or the electrodes of a discharge lamp are accurately located with respect to the cap, the lamp has a glass base member forming part of the lamp envelope through which the leading-in conductors extend so as at least partly to support the filament or electrodes, at least one further member unconnected internally of the envelope to the filament or electrodes but accurately positioned relatively thereto being provided which frictionally engages and secures the cap to the envelope so that the filament or electrode is accurately positioned with respect to the cap. In the form shown, the envelope 1 of a projection lamp is sealed to a glass base 4 through which pass leading-in conductors 7 and one or more stub leads 13 which engage eyelets 14 in the cap 3. The filament 2 is of flat form consisting of a series of flat sections supported by arms 8 sealed into glass, beads 9, the beads being mounted on frame members 5 connected to the leading-in conductors 7 and to the ends 6 of the filament. The stub leads 13 may be secured in the eyelets by soldering. The invention may be applied to lamps in which the cap forms one of the supply conductors, any member other than the further member, which is sealed into the base and assists in securing the envelope to the cap being connected to the filament or electrode.