Patent GB-472010-A (GB)
Title: Improvements in and relating to machines for welding metal vessels or containers
IPC: B23K9/028
Filed: 1936-10-19
Abstract: 472,010. Making hollow-ware. BRITISH THOMSON-HOUSTON CO., Ltd. Oct. 19, 1936, No. 28384. Convention date, Oct. 19, 1935. [Classes 83 (ii) and 83 (iv)] Uniting by fusion.-In an apparatus for welding substantially closed containers, such as stainless steel liners for beer barrels, the complementary parts are supported in assembled relation opposite the welding agency by rotatable means through which extends a shaft carrying an internal backing member, which is normally held out of contact with the work, but may be forced into engagement therewith by means acting on the shaft. The welding agency may consist of a gas torch, arc electrode, or a gas arc torch 13 such as is described in Specification 400,675, [Group XI]. The parts 10, 11 may be gripped in the vicinity of the seam 12 by the jaws 18 of a pair of chucks 14, 15 respectively carried by a headstock 16 and by a longitudinally movable tail stock 17. The jaws are closed by links and levers operated by fluid pressure cylinders 79, 80, and are rotated by a motor 26 through worm and spur gear and hand operated clutch. The joint is supported by a backing member consisting of a water cooled roller 54, Fig. 9, mounted in a yoke 55 on the curved end of a shaft 56, which passes through the part 11 of the container and through the tail stock and is longitudinally movable in a sleeve 63, Fig. 14, carried by a pedestal 66. The sleeve rests on a spring-pressed block 64 and carries a pair of arms 69, 70, of which the arm 70 is connected to the piston rod of a fluid pressure cylinder 72. When the parts are clamped in assembled position, the shaft 56 is first rotated by operation of the arm 70 to bring the backing member under the seam. When the arm 69 engages a stop 68, further movement of the arm 70 lowers the block 64 and tilts the shaft 56 so that the backing member presses against the seam. When welding is complete the welding head is removed to inoperative position, the chuck 14 is released, the shaft 56 returned to a position in which the member 54 points directly in front and after withdrawal of the tail stock the chuck 15 is released and the article removed over the end of the backing member. The shaft 56 is provided with a conduit for supplying gas to the underside of the seam, the gas being hydrogen when using a torch such as 13. The yoke is surrounded by a sleeve 60 to form a chamber enclosing the gas. In order to prevent explosions, a combustion supporting gas, such as air, is fed into the container through a valved passage 73 and work positioning device 74, secured to the chuck 14, Fig. 5, and having a perforated positioning pin 75 passing through the part 10 of the container. The part 11 is positioned by a pin 77 on a similar device 76 engaging a projection 78 on the part 11. The welding head is carried by a shaft 29, Fig. 4, which is mounted on a bracket 30, 31, pivotally mounted on a hollow shaft 32. In order to adjust the head transversely of the seam, the shaft 29 has an arm 33 projecting between a pair of blocks 34, 35 normally pressed by a spring 36 against a stop 44 and pushed inwards by a bell-crank 38, connected by a rod 39 to a spring-pressed lever 40 engaging a cam 41 on a hand-operated shaft 42. The head is raised to an inoperative position, to facilitate loading and unloading, by fluid pressure from a cylinder 47 through rods 46, 45 connected to the part 30 of the bracket. The operative position of the head is adjusted by a bifurcated bell-crank 48 engaging the pin connecting the rods 45, 46 and adjustable by a hand operate screw 50. A tiltable shield 103 protects the operator and has a screen 105. The tail stock is moved along guides 97 by a fluid pressure cylinder 98 and engages adjustable collars on the shaft so as to push it axially to facilitate the loading and unloading operations. All the fluid pressure mechanisms are controlled by hand or foot-operated valves, the fluid being supplied from a tank 91 by a rotary pump provided with a check valve 93.