Patent GB-610404-A (GB)
Title: Improved lattice forming and welding machine
IPC: B23K11/00
Filed: 1946-04-03
Abstract: 610,404. Making lattice girders. BRITISH FEDERAL WELDER & MACHINE CO., Ltd., and TRIBE, T. F. April 3, 1946, No. 10250. [Classes 83 (ii) and 83 (iv)] Straightening; corrugating; welding.-A machine for making lattice girders by bending and welding comprises a spinner to straighten and descale the bar stock, a feed table for feeding the bar stock continuously in predetermined lengths, an adjustable bending machine to create the zig-zag formation of the stock, means to feed bar stock to form the flanges of the girder and resistance welding machines for welding the lattice to the flanges, the spinner having a rotatable body supporting a number of transversely adjustable dies. The stock 50 passes through the straightener S and is fed by a table T<SP>1</SP> reciprocated on guides 11 by an adjustable arm 12 actuated from the driven shaft 13 which is driven through reduction gear 14 from a shaft 15 driven by belt gear from a motor 16. The table is clamped to the stock during its forward movement by pneumatic clamp 18 operated by an electrically-controlled valve 19 actuated by a contact cam 20 on the shaft 13. The stock passes through a bend follower F reciprocable on guides and held normally in its initial position by a counterweight or spring and provided with a pneumatic clamp 22 which is actuated by an electrically-controlled valve 23 from a contact cam 24 on a shaft 28 coupled to the main shaft 15 through reduction gear 29 so as to grip the stock during the rearward motion of the feed table T<SP>1</SP>. The follower is set in a predetermined start position to suit the depth and pitch of the lattice. The stock passes over a die 35 on a bending arm 54 to a clamp table C having a pair of clamps 55, 56 operated by an air cylinder controlled by an electrically-operated air valve 26 actuated initially on setting by a push-button control and subsequently by a contact cam 27 on the shaft 13. Clamping is effected when bending is to be performed. The bending arm 54 is pivoted at 36 and connected by a lever 33 and links 34 to a piston-rod 30 operated by opposed air cylinders 31, 32, controlled by an electricallyoperated air valve 37 actuated when being set initially from a second push-button control and thereafter a contact cam 38 on the shaft 28. The die 35, which is adjustable along the arm to suit the pitch and depth of the lattice, bends the wire to the desired angle, the follower gripping the wire and being drawn forward so as to pull a further length of wire through the feed table and spinner. The clamping dies which may clamp the wire at 45 degrees to the direction of feed may be removable and replaced by dies to clamp the wire at 60 degrees. One of the dies carries an adjustable extension 49a to accommodate lattices of different depths and pitches. After bending a length of stock, the clamps and bending apparatus return to initial position and the formed lattice is fed forwards on the next stroke of the feed table. At the same time the flange wires 41, 42 are fed manually from a hopper to a feed table T2 on which they are gripped by pneumatic clamps 43, 44 controlled by air valve 57 from contact cam 58. The table is reciprocated on guides 45 by an adjustable arm 46 in synchronism with the table T<SP>1</SP>. The lattice and flange wires are moved over guides to the welding machines W<SP>1</SP>, W<SP>2</SP>, W, W 4 , arranged in staggered relation. The machines are adjustable laterally and longitudinally by hand wheels and the welding heads 51, 52 are shaped to weld the flange wires to the crests of the lattice. All four machines may weld simultaneously in alternate cycles of operations, or two welds may be made at a time, the other two machines being used to press the lattice and flanges firmly together. The machines are controlled by -electrically-operated air valves 59. If desired, four lattice girders may be welded together to form a box girder. The spinner S for straightening and descaling the wire, which is rotated at high speed by a belt from a motor 65, is formed with transverse headed slots 67 and inspection openings 74 and central aperture 68. The slots carry dies 70 having central apertures 71 and adjustable transversely by bolts 72, 73. The apertures may be arranged in staggered fashion with that at the point remote from the entry point central, or the trailing die may have a central aperture and the others arranged at progressively greater distances all on one side of the longitudinal axis. Thus, either a sinusoidal movement or a cork-screw movement may be imparted to the wire. A combination of such movements may be given. Specifications 610,405 and 610,406 are referred to.