GB658368A - Improvements in and relating to filament support wire forming apparatus - Google Patents

Abstract

658,368. Supports for electric lamp filaments. BRITISH THOMSON-HOUSTON CO., Ltd. July 22, 1949, No. 19355. Convention date, July 23, 1948. [Class 39(ii)] In apparatus for bending the filamentsupporting wires of lamps having a long helical filament mounted on closely arranged supports, as in train headlights or spotlights, a stem 1, Fig. 4, with exhausting tube 12, and wires 2, 3 radiating from a button 6 at the end of an arbor 7 is located horizontally with the button positioned in a die-block 9, Fig. 1, and a manually-operable knob 5 at the front of the apparatus is pushed inwardly to move a wire-bending or forming head 8 from an axially offset position near the front of the apparatus to a position in axial alignment with the stem 1, the movement being continued axially towards the die-block to bend the wires around the end and over the surface of the die-block. The front edge of the die-block is notched radially to receive the wires 2, 3 which, when the stem is inserted in the apparatus, are arranged as shown in Fig. 4. Movement of the forming-head 8 is effected by providing it with a,lower extension 18 which grips the operating rod 17 carrying the knob 5, the lateral component of the movement being derived from a pair of oblique cam faces 19, 19', Fig. 2, providing a guide channel through which the extension 18 passes. The wires 2 are the first to be bent, by pivoted fingers 20 located in radial planes which intersect at a common point on the axis of the forming-head 8, the number of fingers corresponding with the number of wires 2, there being three in the example. As the head 8 advances, the fingers 20 engage and wipe the outwardly' extending portions of the wires over the rim and outer face of the stationary dieblock 9. The wire-engaging edges of the fingers 20 have each a groove to receive a wire, which is given a right-angled bend, and with continuing advance of the head 8 the bends are maintained by hold-down fingers 28 which are clamped in the head radially inwardly of the respective fingers 20. The parts of the wires 2 held horizontal by the fingers 28 are disposed along the outside faces of a movable die-block 27 and given a further right-angled bend near their ends by bending them around the rear of the die-block. This latter bend is also effected by the fingers 20, each of which has an outwardly projecting pin 31 positioned to engage the face of a fixed cam 32. The bending of the shorter support wires 3 is effected midway in the movement of the bending-head 8 and just prior to the final bending of the wires 2, the wires being engaged by a pair of fixed bending fingers 46 which lie within grooves in the head 8, between the fingers 20. The wires 3 are thus bent at right-angles over the outer face of the die-block 9. Specification 390,807, is referred to.