GB381655A - Improvements in or relating to methods of and devices for forming supporting wires for filaments of incandescent lamps and the like - Google Patents

Abstract

381,655. Making electric lamps. NAAMLOOZE VENNOOTSCHAP PHILIPS' GLOEILAMPENFABRIEKEN, 13D. Emmasingel, Eindhoven, Holland. Aug. 11, 1931, No. 22675. Convention date, Aug. 13, 1930. [Classes 83 (ii) and 83 (iv).] Angular bending; dies.-The mounting- wires for the filaments of an electric incandescent lamp are so arranged that the filament is solely supported intermediate its ends by means of eyelets formed by a single helical turn at the ends of a series of mounting-wires secured substantially in the same horizontal plane at the top of a supporting stem, the forms of the mounting-wires b, Fig. 3, being such that in any position of the lamp the filament a<1> is supported by one point only of each eyelet d<1> and has a tendency to bear on a point p<1> at the side of the eyelet adjacent to the support for the mounting-wires. As shown in Fig. 3 the result is obtained by giving the mounting- wires each a substantially right-angle bend. An apparatus for bending the end portions of the mounting-wires at right-angles to the main portions thereof comprises a receiving- head 1, Fig. 5, with a central aperture 2<B> to receive the central glass stem, and an upper portion 2 formed with an upwardly flanged edge 2<A> across which the straight wires radiating from the stem are laid. Mounted above the head 1 is a vertically movable plunger 6 which is arranged within a cylindrical casing 7 provided at its lower end with three jaws 3 mounted thereon on pivots 8 and held normally towards one another by an encircling spring 26. The casing 7 is slidably mounted within a guide 24, its movement being restrained by laterally disposed spring-pressed plungers 18 bearing upon its periphery. During the downward movement of the plunger 6 a collar 9 thereon engages an internal shoulder 25 on the casing 7, thereby depressing the latter and forcing the jaws 3 on to the filamentmounting wires, which are bent upwardly by the flanged edge 2<A> of the head 2. The lower end 16 of the plunger 6 is shaped conically so that when the plunger begins to rise the jaws 3 can be pulled inwardly away from the bends in the wires by the spring 26, the member 7 meanwhile being held stationary by the plungers 18 until a collar 10 on the plunger 6 strikes a cap 11 at the upper end of the casing 7, causing the latter to be raised to its highest position.