GB795589A - Electric welding and soldering gun - Google Patents

Abstract

795,589. Welding by pressure; soldering. SVENSKA AKTIEBOLAGET GASACCUMULATOR. April 4, 1956 [April 5, 1955], No. 10303/56. Class 83 (4). In an electric arc stud welding or soldering gun having a chuck for a stud provided with a fuse-wire extension, a current supply member is arranged in the gun inwardly of the chuck to contact the wire extension, electrical insulation being provided between the chuck and the supply member. In an embodiment an iron core 5 is disposed between insulating rings 3, 4 in a gun body 1 and about a slidable shaft 6 of non-magnetic metallic material having a flange 7 of magnetizable material. A copper alloy spring 9 wound with double turns rests against the flange 7 at one end and against a metal ring 11 at the other end insulated from the core 5. The ring 11 is connected with a conductor 15 of a contact arm 16 which may be pressed by a knob against a contact 18 connected to a supply cable. Screwed into the outermost end of the shaft 6 is a current supply member 20 having a central hole 21 and an apertured asbestos cap 22 is provided adjacent the member 20. Also attached to the end of the shaft 6 is an insulating sleeve 29 having a metal insert 30 to which is screwed the base 31 of a chuck 32, the base holding an insulating cap 34. A support 36 holding a porcelain ring 38 is threaded to the body 1. In operation a stud 39 having solder at its outer end and a fuse wire 40 at its inner end is inserted in the chuck so that the wire 40 enters the hole 21 in the member 20. A stop 61 on the inner end of the shaft 6 prevents the swinging of the contact 16 until the stud is pressed on to the work sufficient to rest the ring 38 on the work. The knob is pressed and current passes via the contact 16, spring 9, shaft 6, member 20, fuse wire 40 and stud 39 to the work. Current passing through the spring 9 energizes the core 5 to pull the flange 7 inwardly to lift the stud and start an arc. When the wire 40 fuses current is interrupted and the spring 9 thrusts the stud on to the work. After removing the gun a rod 25 in the shaft 6 is pressed by a knob 26 on the rod to push a needle 24 through the hole in the supply member to clean the hole. In a modification the supply member has an arcuate channel for the fuse wire, a cleaning needle on a pivoted arm being provided in the channel. In a further modification the supply member 50, Fig. 3, has a clamp member 51 on the end of a spring 56 to press against the fuse wire 40. An arm 58 on the clamp 51 engages a stop 59 when the stud is thrust downwardly to swing the clamp and allow a member 57 to clear away the remaining fuse wire. Specifications 710,722 and 758,473 are referred to.