Patent GB-118138-A (GB)
Title: Improvements relating to Electric Welding.
Inventor: CARY SPENCER CONE
IPC: B23K11/06
Filed: 1917-08-10
Abstract: 118,138. Cary, S. C. Aug. 10, 1917. Tubes.-In the electric-welding of sheets of metal to form tubular articles, the surface oxidization is removed from the marginal portions of the sheets by a sand-blast, the sheets are then secured in holders and adjusted to engage a gauge, are then trimmed by shears preferably associated with the gauge, and are then welded and rolled to the original thickness of the sheets by a reciprocated rolling electrode and a stationary electrode, or between a pair of reciprocated roller electrodes. In the construction shown, the stationary electrode comprises a bar A bevelled at the top and seated in a pillar C attached to the arms C', Fig. 5. The electrode B comprises a solid roller bevelled at the edge b and mounted in a swing arm D on a reciprocated carriage E running in the arm F. The arm D is normally held up by a spring G, and pressed down by plungers g<1> arranged in the side of the carriage E, Fig. 10. A reciprocated frame J operated by.a screw connected to a motor L through reversing toothed gearing is connected to the carriage E by a link J<1>. The direction of rotation of the screw I is controlled by a clutch actuated by a lever on the shaft n which carries also a lever O having cams o which engage a roller 21 on a spring-controlled lever 32. The lever O is shown holding the clutch in the middle position and is manually controlied by tappets on a lever 10 provided with a toe-piece engaging a. catch 14 controlled by a pedal 19. On depressing the pedal, the reversing mechanism is actuated to enable the motor to actuate the screw. A pin 31 on a head j<1> of the carriage J engages tappets 29, 31 on a rod 22 to actuate the reversing mechanism automatically. After each reciprocation, the clutch controlling the reversing mechanism is brought to its middle position to disconnect the motor by the lever 0 which then engages the latch 14. On either side of the stationary electrode A, Fig. 2. are two brackets 33, 34 carrying sheet-metal work-holders P, Q respectively comprising pivoted clamps p<1>, p<1> depressed by cam levers p<2>, q<2> on to bases p, q. The holder Q is stationary, and P is transversely adjusted to position the marginal portions of metal by means of an eccentric 36 controlled by a lever 39, Fig. 2. The edges of the sheets are positioned by a gauging-device subsequent to their introduction into the work-holders. Such a device comprises a bar 43, which is suspended on a bar 40 and can be swung up and locked in the position shown in Fig. 5. The bar 43 is recessed beneath to engage the bar A and has two surfaces in different planes separated by a projection 47 against which the edges of the plates are brought, Fig. 6, after being cleaned by the sand-blast. The plates are then clamped cown, the bar 43 is removed, and the edges trimmed and overlapped. In the construction shown in Fig. 7, the bar 43 of the gauge is provided with pivots for a cutter head 52 carrying two blades which, on actuating a treadle lever 68 against the resistance of a spring, trims the sheets and enters slots 51 in the bar 43, Fig. 9. The head 52 is connected to a crank 60 with a lug 62 mounted on a shaft 40, and is actuated by a lug 63 on a crank 64 connected to the lever 68. The cutting-mechanism and the gauge 43 are moved over the electrode by a handle 45. The transformer is housed in the body of the machine away from the carriage carrying the roller electrode. The electric equipment includes a primary coil 70, a regulator 71, a secondary coil 80, a controlling solenoid 72, and switches 73, 74 and contacts 75, 76 connected by conductors 90, 91 to the solenoid and switches. The cut-out S comprises a stationary contact 75 and a movable contact 76 on a vibratorv arm 77 under the control of a spring 78. The switch 76 is controlled to make and break the current at the beginning and end of the movement to the left of the roller electrode by tappets 86, 87 connected to a bar 88 carried by the carriage E. The sheet is initially cleansed by a sand-blast provided by nozzles 93, 94 flexibly connected to links 95 which move them across the margins of the sheets'. In the modification shown in Figs. 23 and 24, both electrodes comprise rollers connected to a reciprocated frame 101 containing the transformer 102. The frame 101 is reciprocated by screw and nut gearing actuated through toothed reversing- mechanism 122 actuated by an electric motor. The feed-nut has variable lost-motion with respect to its bearing 116. Reversing means comprises a bar 123 with stops 124, 125 adapted to operate a lever 126 associated with a reversing clutch. The stop 125 operates a releasing-lever 127 controlling a detent 128<a> which engages a catch on the lever. A reverse movement of the lever 126 is secured by pedal mechanism. 130 - - 133. The rollers A<1> are cooled by circulating water, and are positively driven, the motion being dependent upon that of the housing and the speed of rotation being varied by the mechanism shown in Fig. 24. The wheels 136, Fig. 23, are connected up to wheels 137, 138 which register with a wheel 139 engaging a rack 140 which slides in a box 141 and engages a wheel 142 in engagement with a rack 145 moved by a lever 147 having one end working in a slotted bar the inclination of which determines the speed of the rollers. In this construction, the movement of the housing actuates a bar 180, carrying spring- controlled tappets 177, 178, which actuates switches which control a switch for making and breaking the primary circuit of the transformer supplying the welding-current.