GB807631A - Improvements relating to stud or pin welding or brazing tools - Google Patents

Abstract

807,631. Welding by pressure. CROMPTON PARKINSON Ltd. Nov. 9, 1956 [Nov. 21, 1955], No. 34343/56. Class 83 (4). In an electric arc stud welding or brazing gun an elongated stud carrier 24 is retracted against a spring 33 by means of a solenoid 37 controlling a slidable hollow armature 40 surrounding the carrier and clutched to it under the effect of the retractive force produced by the solenoid. In an embodiment an insulating body 10 encloses a casing 38, for the solenoid 37, having a flange 39 at one end providing an external path for magnetic flux and a bushing 42 at the other end. A fixed hollow core 41 secured to the bushing forms an inner path for the flux with the hollow slidable armature 40 which latter is pressed to the right by a spring 45 between a flange 46 on the armature and the end of a body cap 12 to form an air gap 47. The stud carrier 24 carrying a chuck 21 slides within the armature in bearings 31, 32 and studs fed from the rear end of the gun through a central bore in the carrier are in turn pushed past a spring-loaded dog 30 into the chuck. The spring 33 urges the carrier into engagement with a shoulder on the front bearing 31. A clutchring 50 encircling the carrier and pressed against the bearing 31 by a spring 51 is engaged on one side by a lip 53 on the arm 40. In operation with a stud 20 in the chuck pressed against the work the carrier slides within the armature against the spring 33 and when the solenoid is energized the armature is retracted to lock the ring 50 on the carrier to clutch and withdraw the carrier a distance equal to the width of the air gap. On de-energizing the solenoid the carrier is returned by the spring 33. Specification 580,702 is referred to.