GB560500A - Improvements in or relating to the joining of wires, particularly fine wires used inthe manufacture of electric coils - Google Patents

Abstract

560,500. Uniting by fusion. STANDARD TELEPHONES & CABLES, Ltd., and GILLIVER, G. Oct. 2, 1942, No. 13849. Addition to 558,472. [Class 83 (iv)] Apparatus for joining .wires or thin metal strips .by electric fusion comprises a casing containing two spaced insulatingly mounted electrodes and slots to receive a pair of wires bridging the electrodes and provided with a lid carrying a member for clamping the wires in bridging position on the electrodes when the lid is closed. An apparatus particularly for joining fine wires such as are used for relay coils comprises an insulating casing 11 having a spring-opened hinged lid 10 and provided with slots 13 to receive the wires which are to be fusion welded and which are twisted together. The wires bridge carbon or tungsten electrodes 2, 1, of which 2 is in circuit with a resistance 8 and block 15 connected to one terminal of the supply and 1 is carried by a spring blade 6 having a contact 5 normally out of touch with a contact 4 carried by a blade 7 in circuit with a block 12 connected to the other terminal of the supply. When the lid is closed a carbon block 3 carried thereby clamps the wires against the electrode 1 and closes the contacts 4, 5 so as to fuse the wires producing a globule, uniting them together and cutting off the supply. The lid may have a separate press button for connecting the current supply. The casing may be fixed to a bench or may be formed as a pistol handle and the lid closed by a trigger. In another form a two-part insulating handle 39 contains contact blocks 42 connected to the terminals of the supply. One block carries a metal blade 19 with a press button 46 and a contact 44 normally out of touch with a contact 45 on a metal member 16 secured to an insulating block 18. The member 16 carries a spring blade 17 to which a carbon electrode 31 is secured the blade normally pressing the electrode forwards and being slotted to engage the head of a screw 20 so as to limit its forward position. On the block 18 are mounted a pair of members 47 provided with holes 43 and connected to the other terminal of the supply. Between the members 47 is mounted a spring-controlled slidable member 49 provided with a hole 48. The members 47 and 16 are surrounded by a shroud 41 carried by the handle. The member 49 is pushed forward by a trigger 50 so that the holes 43, 48 are in alignment and a pair of wires twisted together and' cut off level or placed parallel and close together are passed through the holes and push back the electrode 31 until it engages a stop 40 carried by the member 16, whereupon the trigger 50- is released and the wires clamped by the action of the spring 38. The button 46 is then depressed to connect the electric supply and the ends of the wires fuse together allowing the electrode 31 to move away from the member 16 until stopped by the screw 20, whereupon the circuit is broken by the wires being out of contact with the electrode 31. Trigger 50 is then again actuated and the welded wires removed. Such apparatus may be used for electric communication cables and may be modified to form a bench fitting..