GB588942A - Improvements in electric discharge tubes - Google Patents

Abstract

588,942. Discharge lamps. LUMALAMPAN AKTIEBOLAG. Jan. 29, 1945, No. 2235. Convention date, Feb. 18, 1944. [Class 39 (i)] [Also in Group XXXVI] The base of a discharge lamp comprises a cup-shaped member 7, Fig. 2, having a slot 8 in the bottom wall thereof which is closed by a detachable disc or plug 11 carrying a relay, e.g. a glow switch 17, the relay being connected to the contact member 14, Fig. 3, of the base and also to the electrode 2. The profile of the disc 11 and slot 8 is preferably a circle cut off by two parallel chords of equal length, as shown in Fig. 3, and part of the thickness of the edge portions 22, 25 of the disc 11 is cut away so that the disc can be locked in the slot by turning engagement. The leading-in wires 12 of the glow switch 17, the lead-in wire 19 to the electrode 2 and a connecting wire 15 to the contact member 14 are clamped in the disc 11 by radial screws 9, and the other lead-in wire 18 of the electrode 2 is connected to the contact member 21, as shown. Alternatively, the glow switch may be welded to the disc 11 or the disc may be shaped as a container for the glow switch. In a modification, Figs. 5, 6 (not shown), the disc 11 is provided with metallic contacts to which the lead-in wires of the glow-lamp are soldered, and which co-operate with contact plates attached to the bottom wall of the base so that the circuit is automatically completed when the disc 11 is inserted within the base.