GB191224571A - Improvements in or relating to Incandescent Electric Lamps. - Google Patents

Abstract

24,571. Harrison, F., and Harrison, F. L. Oct. 26. Filaments, supports for; filaments, attaching; repairing; leading-in wires; reflectors within bulbs.-A number of radial spring supports on a central insulating stem are adapted to grip a metal filament and the leading-in wires and allow the filament or any section thereof to be undamped for renewal. In the example shown. radial supports having helical outer ends e<2>, preferably provided with arms e<1> for opening the helices, are attached to a tubular glass stem a adjacent to the tip of the bulb, a number of hairpin filaments suspended from upper hooked supports d being clamped in the helices and connected in series as shown. The leading-in wires b pass down the stem and are similarly clamped. In repairing, the damaged filament is withdrawn through a hole g at the tip or elsewhere, the bulb cleaned if necessary, for example by heating its exterior, and the ends of a new filament secured after opening the helices by means of a rod or blade adapted to move the arms e<1> towards or away from the main supports; or the helices may terminate in hooks for the reception of the opening device. The ends of the filament are preferably dipped into sealing wax or other coloured material to enable them to be easily located, the coated parts being broken off after clamping.' In other forms, the stem may be of clear, white, or coloured glass of any cross-section optionally silvered to act as a reflector, or a solid stem of glass, kaolin or the like may have grooves for the reception of the leading-in wires, or the wires may be embedded in, or pass down the outside of, the stem. One or more lengths of flexible metal filament may be used instead of hairpin sections and thick filaments for heavy currents may be secured to wires adapted to engage the gripping supports. According to the Provisional Specification, the filaments and leading-in wires may be clamped by means of tubes, optionally split, or pasted joints may be used.