Abstract: Welding arc stabilizing and igniting is effected with at least one pulse-forming condenser switched by spark gap or semiconductor switch to deliver a sharp discharge pulse through the winding of a pulse transformer, the magnetic energy thus built up in the transformer being then dissipated by a unidirectional diode bypass of the winding through the switch. The pulses are delivered by the transformer to the welding electrodes, and can be combined with pulses of lower voltage and longer duration by an appropriate series condenser-resistor combination in the transformer output. The pulse-forming condenser can be charged by simple resistor connection to the input of a step-down welding current transformer, or by transformer coupling to any source of AC welding current.

Abstract: A compact, flexible, lightweight welding gun is provided, including a single outer tubular casing substantially containing all the weld gun components. Concentric disposition of annular fume evacuating passageways between the outer tubular casing and component electrical transmitter elements insulates the external surfaces of the casing from the electrical heat sources within the gun, while cooling gases circulating in the gas passageways promote dissipation of accumulating heat. The improved cooling properties of the gun permit relatively higher levels of current and therefore increased speed of weld bead deposition, while the single conduit structure of the welding apparatus renders it more compact, flexible and lightweight, as well as more maneuverable due to the relatively clean exterior of the gun.

Abstract: An arrangement for actuating welding guns to weld weldment components in a predetermined welding pattern wherein the weldment components are movable relative to the welding guns. Movable means are movable in synchronism at a predetermined reduced speed in relation to the speed of the movable weldment components with means on the movable means corresponding with the desired welding pattern to be formed on the weldment components. Scanner means are electrically connected to the welding guns and are responsive to the indicating means to sequentially activate and deactivate the welding guns to weld the weldment components and form the predetermined welding patterns thereon. Limit switch means are electrically connected to the welding guns and means are provided on the movable means to actuate the limit switch means when the weldment components have completed their movement relative to welding guns to deactivate the welding guns.

Abstract: A small-sized gas ignition device comprising a self-oscillation circuit, a piezo-electric transformer which steps up the output of the self-oscillation circuit, a capacitor which accumulates the output voltage of the piezo-electric transformer, and a discharging gap which is connected in parallel with the capacitor and is adapted to discharge the accumulated voltage for performing gas ignition. With this device gas ignition is obtained with certainty by single operation requiring only a light touch.

Abstract: The invention relates to a welding torch for welding underwater and to a method of underwater welding using the welding torch. A high speed stream of water is directed from a nozzle on the welding torch obliquely onto a member or members to be welded to form a flared-out curtain of water. Gas is injected into the volume enclosed by the curtain of water to create a gaseous atmosphere and welding is carried out in the gaseous atmosphere.

Abstract: The control unit comprises an elongated body having a forward torch mounting portion. Rearwards of the torch the body houses a linear potentiometer which includes an upstanding control arm for its movable contact. An off-on switch is located within said body, in a position to be contacted and operated by the control arm. A thumb button controlled sliding control member is attached to the control arm. In use, the user grips the mid portion of the body and places his thumb on the thumb button. He uses a simple linear movement of his thumb to both control the linear potentiometer, for varying the welding current, and to operate the off-on switch, for turning the arc welding machine on and off.

Abstract: An arc welding power supply of the type which employs a saturable reactor circuit to control the supply power from an alternating current source to the welding electrode. A control circuit varies the current through the control winding of the saturable reactor to provide the desired welding current. An additional circuit monitors the welding current and disables the saturable reactor control circuit when the welding current drops below a low threshold value, thus reducing the open circuit voltage between the welding electrode and workpiece and minimizing the danger of electric shock to the welder while changing electrodes. The saturable reactor is connected in series with the primary winding of a transformer which also serves as the output winding of the saturable reactor.

Abstract: An electron-beam apparatus for evaporating material is disclosed. The apparatus comprises a rotatable hearth on which the evaporant material can be placed and an electron-beam source which can be energized to evaporate the material. The apparatus is compact and durable because the electron beam source occupies a protected location which is closer to the rotational axis than is the hearth.

Abstract: A D.C. arc welder with solid state components which is provided with means for converting A.C. to D.C. and with controlled diodes serially connected in the D.C. line between the converting bridge and a transformer providing electric insulation between the D.C. line and the terminals of a welding head. A further controlled diode is also connected to the D.C. line downstream of the control diodes and in parallel with the transformer and in series with a capacitor. Between the transformer and the welding head a rectifying assembly is arranged. The serially connected controlled diodes are simultaneously triggered by a pulse amplifier and transformer. A further pulse amplifier and a further pulse transformer subsequently trigger the further controlled diode, whereby the serially connected controlled diodes are turned off.

Abstract: A method of and means for cutting hose of the type designed for use in high pressure hydraulic systems is disclosed in which the impingement of a high power laser beam is moved about the periphery of the hose in a plurality of passes. An embodiment is described in which the hose remains stationary with the beam being moved thereabout and a further embodiment is disclosed in which the beam remains stationary and the hose is rotated about its own axis. The provision of inert gas to prevent combustion both inside and outside the hose during cutting thereof is disclosed.

Abstract: Apparatus for generating and regulating welding currents, having primary and secondary circuits connected through a transformer, an anti-parallel connection of two thyristors in the primary circuit, a choke in parallel with this anti-parallel connection and means which shift the phase of the turn-on pulses in the case of a short-circuit on the secondary side and in switching on.

Abstract: A DC arc welding apparatus using a high-frequency pulse current is disclosed and includes a rectifier bridge for commutating AC voltage and for applying DC voltage having a substantially smooth waveform to a circuit including an electrode and a workpiece for welding. A first switch is connected between an arc load formed between the electrode and the workpiece and a positive output side of the rectifier bridge. A second switch is connected between the arc load and a negative output side of the rectifier bridge. A capacitor has one end connected to a contact of the rectifier bridge and the first switch and another end connected to a contact of the rectifier bridge and the second switch.

Abstract: A method for controlling flashing speed during resistance butt welding comprises measuring values of current density for at least two joints between parts being welded, converting them into d-c. voltages, detecting a maximum voltage value, comparing it to a preset d-c. voltage, the resultant difference value being used as flashing speed control parameter. An apparatus for carrying out the method comprises electric circuits whose number is equal to the number of joints being welded. Each circuit comprises a welding transformer and a circuit for conversion of flashing current density into d-c. voltage. A maximum signal detector comprises circuits for conversion of current density into d-c. voltages, whose number is equal to the number of joints being welded. The detector output is connected to the circuit for comparing a current voltage value to the preset one.

Abstract: The proposed apparatus comprises an arc-welding source, including a current pulse generator with a control circuit and a rectifier.A choke at the output of the rectifier is connected to the electrode-article gap, in series with the rectifier of the pulse generator. The rectifier is a fullwave rectifier and comprises two controlled thyristors and two uncontrolled diodes. As the apparatus is in operation, one of the thyristors becomes conducting during each alternating current half-cycle. Current pulses pass through the arc and choke and are added to the pedestal of the current that continuously flows from the rectifier through the welding circuit.

Abstract: Apparatus for indicating the time and welding current of a welding cycle is provided, along with means for monitoring the welding current and for preventing further welding cycles if the current is outside certain preset limits. The invention is used with stud welding apparatus in which a stud is placed against a workpiece, then withdrawn, and at the same time a pilot arc is formed; subsequently, a main welding arc is established which forms pools of molten metal on the stud and on the workpiece, the metal solidifying when the stud is subsequently plunged against the workpiece, thereby completing the weld. The length of time of the welding cycle and the welding current flowing during the existence of the main welding arc have, of course, heretofore been measured under laboratory conditions. However, such has not been accomplished under field conditions with commercial stud welding apparatus and particularly where such is accomplished by measuring both the welding time and welding current on a single meter.

Abstract: Resistance welding apparatus having a power driven welding head carrying a first welding electrode for co-operation with a second welding electrode, wherein the head is switched from a low-force approach operating mode to a high-force squeeze operating mode only when the welding electrodes electrically contact one another, either directly or through a workpiece therebetween, so that no gap exists in which an operator's hand or finger can be crushed between the electrodes upon transition from low-force to high-force operation.

Abstract: The invention relates to an improved method of automatic or semi-automatic welding with gas, or brazing, effected by using a coil of fillet wire brought to the welding point by continuously passing through the center of a gas flame, (oxy-acetylene, oxygen-propane for example) which melts the wire and heats the work part, said improvement comprising the application of an electrical voltage between a member mounted on the forward-movement path of the fillet wire and the work part under treatment, so as to cause the passage therein of a heating current.The electrical voltage is preferably applied either between the welding torch nozzle or the forward-movement rollers and the part treated.

Abstract: A constant potential single phase A.C. power welding source is connected to a thyristor network and an energy storing inductor to create a square wave welding current that is adjustable in height, and is further adjustable to allow either half-cycle to be wider than the other, the sum of two adjacent half-cycles always equaling 360.degree.. The welding current is forced to reverse rapidly by a substantial voltage to insure conduction when the welding load is an arc to an aluminum work piece, and the aluminum tends to rectify. The heights of the positive and negative half-cycles are simultaneously adjustable in response to manual control and feedback signals.

Abstract: A direct current power supply for manual arc welding comprising a polyphase transformer, a polyphase rectifier system including triggered rectifier valves, and a control system therefor which comprises means for setting the output current level by adjustment of a reference signal, means providing negative feed-back of the output voltage and the output current, and means for adjusting the slope of the characteristic by adjustment of the proportion between the amounts of feed-back of the voltage and the current. The current level setting means and the slope adjustment means are linked with each other to provide automatically a desired correlation between the slope and the current setting.

Abstract: A direct current power supply for manual arc welding having a steeply drooping, adjustable characteristic, comprising a polyphase transformer and a polyphase rectifier system including triggered rectifier means and a control system therefor providing both welding current and welding voltage feed-back. The welding current feed-back is substantially fixed. The welding voltage feed-back is adjustable for adjustment of the slope of the characteristic.