GB1450454A - Method and apparatus for connecting two or more wires - Google Patents

Abstract

1450454 Making electrical connections; welding by pressure; shearing S WARNER 19 Sept 1973 [19 Sept 1972] 44058/73 Headings B3A B3R and B3W In connecting two or more wires, terminal material is shaped about the wires to produce a profile elongate in one direction, current is applied to the assembly to soften the material and wires, the material and wires are compressed and the pressure is controlled to cause the profile to elongate in a direction generally perpendicular to the said one direction. An embodiment of a machine for performing the connecting comprises a frame 10, Fig. 1, mounting an upper, terminal forming assembly 18 and a lower, terminal guide and electrode assembly 16. A mechanical drive 20, electrode power circuits 22 and timing control circuits 24 are also carried on the frame, the circuits 24 including means for automatically testing the weld quality and generating a reject alarm. A reel 26 of copper, brass, steel or nickel ally strip 28 is mounted on the frame 10 and wheels 34, 36 are arranged to be driven through one complete revolution to advance strip from the reel 26 only when the arc 37 on wheel 36 opposes wheel 34. The strip is serrated by rollers 52, 54 and is fed through a guide channel 84, Fig. 6A, in assembly 18. The assembly 18 includes a casting 62, Fig. 7, comprising an upper cavity 64 housing an eccentric drive assembly 66 and a lower cavity 68 housing an anvil assembly 70. A block 72 co-operates with the housing front cover 74 to form a slide way for a carried assembly 76 and ram assembly 78. The guide channel 86 is formed in a cutting block 80 secured to the casting 62 at the bottom of the slide way. The eccentric drive assembly 66 is driven from the drive 20 to rotate 180 degrees in one direction and then 180 degrees in the other and through a pin 92, link 94 and pin 99 drives the ram assembly 78. The eccentric drive 66 also drives the guide carrier 76 by the pin 92, link 97 and pin 91, the carrier 76 carrying at its lower end left and right guides 15 and 17 which receive between them the ram 25 carried at the bottom of ram assembly 78. The guide 17 co-operates with the cutting block 80 to form a cutting surface. An anvil 31 of the assembly 70 is spring urged into the slide way opposite the ram 25 and has a cam surface 33 which can be engaged by the guide 15 to rotate the anvil away from the slide way. The assembly 16 comprises a die assembly 41, Fig. 12, mounted for vertical reciprocation in alignment with the ram 25 and having a die plate 43. A cutter blade may be mounted for independent vertical reciprocation behind the die plate carrier 45. A cam plate 55 having slots 57, 59 is horizontally reciprocated to vertically reciprocate the die plate carrier and cutter plate, rollers 65, 67 being engaged in the slots. A pair of electrodes 75, 77, each having four electrode surfaces, made available by rotating the electrodes through 90 degrees, are reciprocable horizontally on the frame 10 by means of an eccentric drive 89 coupled to slide blocks carrying the electrodes. The electrodes may be of low resistance metal, e.g. copper or high resistance material. In operation a length of strip is fed from the guide 84, the ram 25 and guides 15 and 17 are lowered so that the guide 17 severs the projecting strip and the guides and ram are further lowered to form the severed end into U-shape about the anvil 31. Further movement of the guides causes withdrawal of the anvil 31 from the slide way and finally the guides nearly abut the die plate 43 in which are located two lead wires. The ram movement continues forcing the U-shape about the lead wires and if a cutter plate has been fitted it moves relative to the die plate and severs the wires. Then the ram and guides are raised and the die plate is lowered leaving the terminal strip end leads free. The electrodes are advanced to engage the strip end and supply current and pressure to burn off insulation, weld the leads and terminal strip and squeeze the assembly to an elongated shape as shown in Fig. 20. The lead wires may be led from opposite sides into the die cavity when the cutter plate is not used. The wires may be of aluminium or steel copper alloy, insulated or uninsulated. Reference has been directed by the Comptroller to Specification 1,123,464.