GB204774A - Improvements relating to electric incandescent lamps and to lamp-holders therefor - Google Patents

Abstract

204,774. Workman, H. July 5, 1922. Caps. - A lamp for motor-car headlights or other use requiring accurate location of the filament with regard to a reflector or optical system is provided with a fitting- piece secured to the lamp cap and having two or more outwardly-turned flat lugs which are held by spring pressure in contact with a recess in the rear surface of a flange in the lamp-holder so as to bring the filament to a standard position. The fitting-piece consists of a tube e with a lower end f of reduced diameter which fits the lamp cap b somewhat loosely so that during assembly in a temporary fixture the lamp may be adjusted axially and swung transversely until the filament occupies the standard position. The tube e is then secured to the cap by means of cement or solder f. Lugs h, k, l secure the lamp in a bayonet type of holder, and one of them, such as k, is larger than, or of different shape from, the others to ensure correct angular positioning of the lamp in the holder. In alternative forms, the lugs may be made by slitting the end oi the tube e and bending out the strips between the slits, or the tube may be mounted with its narrow part f adjacent to the lamp bulb and its wide part e directed towards the contacts on the lamp cap. Holes or openings may be provided in the tube for passage of the solder or cement. The device, which is applicable to single or double contact caps, is suitable for use with holders as described in Specification 204,464.