Patent GB-671492-A (GB)
Title: Improvements in automatic lead wire threading apparatus
IPC: H01J9/28
Filed: 1949-11-16
Abstract: 671,492. Apparatus for capping electric lamps, discharge devices &c. SYLVANIA ELECTRIC PRODUCTS, Inc. Nov. 16, 1949 [Nov. 17, 1948], No. 29369/49. Class 39(ii) Leading-in wires extending in a random direction from an electrical element, such as a lamp or electric discharge device are straightened and positioned by apparatus that operate in sequence and arrange them in readiness for threading into apertures of a co-acting element such as a base or end-cap, the apparatus comprising means for effecting a preliminary positioning of the wires, means for finally positioning them, and further means for clamping them near their outer ends and initiating the threading operation, whereupon the clamping means is withdrawn and the threading completed. In the example tubular lamps 1, Fig. 1, are placed in holding clips 3 upon members 5 which are movable along a straight guideway 6 of a conveyer 4 arranged to be halted at three successive stations A, B and C. The arrangement shown may be duplicated at opposite sides of the conveyer so that both ends of a tube may be operated on simultaneously, the tubes being disposed in a horizontal plane during the operations. Station A is provided with two pairs of wire-manipulating elements, one pair 7, Figs. 4 and 5, consisting of two blocks which are movable vertically towards one another and each formed with a semi-circular recess 8 having a radius slightly greater than that of the lamp. The other pair of manipulators consists of rollers 9 located closely behind the members 7 and arranged to roll the lead-in wires 2 into an approximately straight condition in a horizontal plane after they have been partly aligned by the members 7. The apparatus is supported on a horizontal table 11 on which is mounted a driving shaft 37 carrying operating cams 35, 42, and 70 for the stations A, B and C respectively. A rod 24 controlled by cam 35 extends axially through a slidable shaft 13 supported within a hub 12 and held against rotation by a spline 14. The end of the shaft 13 adjacent to the lamp has a flat-sided head 15, Fig. 5, to the two vertical faces of which are secured supporting plates 16 each provided with two parallel slots 17, 27, the former to receive a pair of laterally extending pins 18, 19 on each side of the manipulators 7, and the latter to receive the ends of shafts 26 supporting the rollers 9. Each manipulator 7 is actuated by a pair of bell-crank levers 20 pivoted at 21 upon the plates 16, the forwardly directed arms of the levers being connected to the pins 19 on the members 7, while the other arms extend inwardly and are provided with vertical slots 22 to receive the ends of a common transverse pin 23 which is secured at its central portion to the rod 24 within the shaft 13. To provide for movement of the rod 24 and pin 23 in order to swing the bell-cranks 20, the shaft 13 is formed with longitudinal slots 25. Movement of the rollers 9 towards one another is effected by two pairs of bellcranks 28 on pivots 29 on the side plates 16, the shaft 26 of each roller 9 being supported by an arm of a bell-crank at each end. The inner ends of the bell-cranks 28 carry rollers which engage the edges 30 of cam members 31 supported on rods 32 anchored rigidly to the stationary supoprt 10. In operation the cam 35 moves the shaft 13 inwardly as soon as a lamp is aligned with station A, and the manipulators 7 are then moved vertically inwardly towards the end of the lamp tube. The rod 24, Fig. 4, is next moved towards the left, and during the initial part of the motion a frictional device 38, Fig. 1, holds the shaft 13 against movement, so that the rod, through the pin 23 and levers 20, closes the manipulators 7 upon the lamp. When the pin 23 reaches the left-hand end of the slots 25 the shaft 13 begins to move with rod 24, and the members 7 engage and partly align the wires. In addition, the rollers 9 on the ends of the bell-cranks 28 are pulled towards one by tensioned springs 33 when those rollers arrive beyond the end of the lamp tube 1 and the rollers on the other ends of the bell-cranks ride off the cams 30. Further movement of the members 7 and rollers 9 causes the wires to be rolled approximately straight before the lamp is indexed to station B for further straightening and re-alignment of the wires. The mechanism at station B comprises a standard 39, Fig. 1, supporting a hollow slidable shaft 40 and an inner rod 41, the upper end of shaft 40 serving as support for a block or crosshead 47a, Figs. 8 and 9, on which top and bottom guide plates 47 and a pair of side guide plates 48 are mounted on studs 49 secured to the crosshead. The studs 49 are shaped to provide a clearance between the guide plates and crosshead, so that the parts of the studs within the space provide pivots for pairs of bell-crank levers 50 at the sides of the crosshead. The outer ends of levers 50 support the shafts of a pair of horizontal rollers 51, and the shafts are extended to engage within slots 52 in the side plates 48, thereby maintaining the rollers in a vertical plane. The other ends of the adjacent levers 50 overlap and have short vertical registering slots into which horizontal actuating rods 53, Fig. 10 (not shown), extend from a head 54 at the end of rod 41. A pair of vertical rollers 55 are mounted between the arms of two pairs of bell-cranks 56 in a manner similar to the mounting of horizontal rollers'51, and the overlapping ends of the bell-cranks are slotted to receive vertical actuating rods 57 extending from the head 54. On the arrival of the lamp at station B the rod 41 is operated to move the sleeve shaft 40 and crosshead 47a inwardly, and the rollers 51 and 55 are opened out. The rod 41 is next retracted while the shaft 40 is held by a friction plunger in a device 63, the movement of the rod alone causing rollers 55 to clamp the lead-in wires against the flat sides of a vertical anvil member 60 which is secured at its ends in the plates 47, and at the same time rollers 51 come together to clamp'the wires at another point. After a short independent travel the rod 41 moves the shaft 40 and the associated crosshead rearwardly, causing both pairs of rollers to position the wires in a predetermined relationship. The lamp is now transferred to station C. Station C comprises operating gear associated with a bracket 65, Figs. 1 and 2, and including actuating-cams on a shaft 67 supported by brackets 66 and driven from the main shaft 37 by bevel gears 85, 86 and pinions 88, 89. At this station three pairs of L-shaped members 92, 101, 120 are pivoted side by side upon a pair of parallel shafts or rods 93 which extend through holes within their angular bends, and each pair has between its longer arms a compressed spring which tends to separate them. A flat-sided anvil 90 located between the arms 92 is arranged to be elevated to engage between the lead-in wires and hold them in spaced relation on either side of it so that they are flattened when the arms 92 are pressed inwardly by upward movement of an actuator plate 96 mounted on a cam-operated rod 123, the ends of the shorter limbs of the L-shaped members being provided with headed bolts to form adjustable abutments to engage plate 96. The.arms 101 are each provided with a vertical aperture to receive a vertically movable actuating rod carrying a head 109 supporting a relatively thin wire-positioning blade 110, the edges of the blades having angularly inclined and horizontal guiding portions. The actuating rods are operated by being pulled downwardly against the action of helical springs at the bottoms of the apertures in the arms 101, this action being effected by the downward movement of a headed member 116, Fig. 13 (not shown) which engages lateral studs 107 screwed into the actuating rods 105 and extending towards one another through longitudinal slots in the arms 101. The arms 101 are swung inwardly simultaneously with the arms 92 by the actuator plate 96, which extends beneath both pairs of arms. The third pair of arms 120, Fig. 14, are swung inwardly by the vertical movement of an actuator plate 122 by the cam-rod 123, and have a longitudinal aperture each to receive a slidable rod 130 with upper and lower wire-positioning members 131 provided with V-shaped slots 132. The members 131 are brought together by movement of rods 130 in opposite directions, this being effected by a rotary hub member 138, Fig. 13 (not shown), pivoted between the arms 120 and provided with oppositely extending non-radial arms one of which engages above an abutment screw 134 projecting from one rod 130 and through a longitudinal slot in arm 120, while the other engages below a similar screw 133 in the other rod 130. Rotation of the intermediate hub moves the rods 130 in opposite directions and in opposition to springs within the arms 120, one spring 135 being compressed and the other, 136, being tensioned. Rotation of the rotary hub is effected through a parallel link system operated by an offset vertical cam rod 143, Fig. 11 (not shown). Capping. A lamp base 74 with pins 75, Fig. 3, is placed in a holder 73, Fig. 2, at the end of a shaft 68, the pins being received in slots 148 in the holder, and the holder is moved forwardly by the cam 70, Fig. 1, until the lead-in wires enter the holes in the pins, whereupon the whole straightening &c. unit 76 and associated elements are moved downwardly out of the way by their respective cams. Further inward movement of shaft 68 presses the base against the lamp tube and the projecting ends of the lead-in wires are cut off and soldered. Preferably the base contains cement to effect permanent adhesion to the lamp. Specification 342,895 is referred to.