GB1236187A - Filament lamp - Google Patents

Abstract

1,236,187. Halogen lamp. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 20 Feb., 1970 [24 Feb., 1969], No. 8293/70. Heading H1F. An electric filament halogen lamp comprising a tubular quartz envelope 1 with a pinch seal 3 at one end, has two series-connected filaments 31, 35, stretched in the longitudinal direction of the envelope, these filaments being connected together at their ends remote from the pinch seal by a brace 37 whose end portions are formed as mandrils screwed into the filament ends and whose centre portion is constituted by a coil 39 of at least three turns 47, 49, 51, looped around a supporting wire 19 which is rooted in the pinch seal. The coil 39 is welded to the supporting wire 19 by all but its end turns. The supporting wire 19 over that part of its length where it runs adjacent the active parts of the filaments is farther away from the longitudinal axis of symmetry of the lamp envelope than elsewhere to prevent it having a cooling effect on the filament, the end supporting coil 39 being bent to lie in the axis of symmetry thus forming a hook, Fig. 2, not shown. A quartz block 21 supports the filaments in position at their ends near the pinch seal.