Patent GB-555360-A (GB)
Title: Improvements in the manufacture of cartridge fuses
IPC: H01H69/02
Filed: 1942-04-14
Abstract: 555,360. Making fuses. BELLING & LEE, Ltd., HODBY, A. L., and STYLES, G. A. April 14, 1942, No. 4921. [Classes 83 (ii) and 83 (iv)] Soldering.-In making a cartridge fuse of the kind embodying a glass or porcelain tube through which passes a fuse wire or element soldered at its ends to metal end caps by melting solder pellets in the ends of each tube by a flame or by electrically or otherwise heated hot plates, the assembled cartridge is spun about an axis transverse to the tube axis while the solder is molten so as to ensure centre-forging of the solder into the end caps. The ends of the fuse wire may be wrapped back on the ends of the tube before inserting the solder pellets which may be formed from solder of half-round section folded back on itself with the curved surface outermost and the bifurcated end enlarged slightly so as to prevent it being inserted too far into the tube. On a base 10 is fixed a post 13 mounting a freely rotatable boss 19 from which radiate two sets of arms, one set 20, 21, 22 for supporting the spindles of jigs 35 in which the assembled parts are carried and the others 26, 27, 28 supporting solder pans 29, 30, 31 for the reception of solder splashed out during operation. Also freely rotated on the post 13 is a sleeve 15 which is driven by worm gear from a variable-speed electric motor 16 and which carries a bevelled disc 14 for rotating the jig spindles by engaging rubber tyred pulleys 32, 33, 34 thereon. The jig spindles contain spring- pressed plungers 36 carrying at their upper ends ejectors 37 and claws 38 between which the assembled parts of the fuse 39, 40 are placed when the jig is at the setting station 12. When the jig reaches this station the spindle runs up a chamfered surface 51 on the pedestal to raise the pulley out of contact with the disc. The spindle is locked in the pedestal by a spring-loaded pivoted catch 47 which must be released before the spindle carrier can be moved clockwise to bring the spindle to the solder-melting station. The plunger 36 is raised so as to remove a finished fuse and insert a new assembly by a spring-returned lever 42 through a tappet 44. When the lever 42 is returned the spring 41 pushes down the plunger and causes the assembled parts to be forced between spring clips 45 on the jig plate. The catch 47 is then released and the jig arm pushed by the operator away from the pedestal towards the solder melting station the spindle dropping so that the pulley 33 again engages the disc 14. When the jig reaches the solder melting station the next succeeding jig is held at the pedestal. The jig is rotated by the disc 14 at the solder melting station, which has a gas jet 49 normally operating on a byepass and fed with gas through a pipe 52 and air through pipe 53. The pipes are led off to a control valve connected to a lever 54 which is operated so as to knock off the gas and air at the desired time by an adjustable projection 58, set by a clock 59 and driven from a pinion 37 engaging a pinion 56 on the sleeve 15. At the third station the solder may be cooled by an air nozzle 50 supplied with air from the same source as the air supply to the pipe 53 such as by a fan unit on the back of the motor 16. The cooling station and the solder pans may be dispensed with.