A method and apparatus for welding include initiating a pulse welding process includes initiating a welding arc by providing CC type welding power, maintaining the arc by providing CV type power. Then, pulse type welding power is provided. The method and system can be used to start short circuit, or other welding processes by providing short circuit power, or welding power of a given mode, instead of providing pulse power. Also, in one alternative, a method and system of initiating a pulse, short circuit, or given welding process includes initiating a welding arc by providing CC type welding power at least until a pseudo-equilibrium for the arc is established. Then, providing welding power in a pulse, short circuit, or the given mode.

Method and apparatus for welding

An electric arc welder including a high speed switching power supply with a controller for creating high frequency current pulses through the gap between a workpiece and a welding wire advancing toward the workpiece, where the pulses and a background current defining a series of weld cycles. A wave shape generator defines the shape of the pulses and the background current including a controlled ramp up and/or ramp down in each of said cycles and a circuit to change the shapes of the pulses and/or background current in a repeating pattern in each of the weld cycles. The shape change in a cycle can be between first and second shapes or by a rhythmic AC modulation.

Electric arc welder using high frequency pulses

In a method for controlling pulse arc welding where an arc is created between a wire and a base material, a pulse waveform different from the pulse waveform for steady-state welding is outputted when a predetermined time has passed since short-circuit welding control was started at arc start, and after a sufficiently large melt pool is formed, the pulse waveform for the steady-state welding is outputted This reduces the generation of spatters after an arc is created and until the arc is stabilized

Arc welding control method

A welding machine includes a power source having a high frequency, zero-voltage switching converter. The preferred power source includes an input rectifier bridge, a zero-voltage switched inverter, a high frequency transformer and an output rectifier. The inverter switches at zero voltage without adding extra inductive or capacitive components, and without increasing voltage or current stresses on the welding machine architecture. A controller operates converter switching devices to turn on at zero voltage. This system avoids switching losses and drastically increases the switching frequency to avoid audible switching noise levels. Advantageously, passive components are reduced in size to yield a more compact welding machine, which is capable of more uniform welding than earlier designs.

Welding machine with a high frequency converter

An arc welding method comprising the steps of accelerating a feeding speed of a welding wire to cause shorting between the welding wire and a base metal when a welding end signal is input during a period of arcing, retracting the welding wire backward thereafter until a wire retracting speed reaches a predetermined rate, controlling the wire retracting speed constant at this speed for a predetermined duration of time, then stopping the backward retraction of the welding wire, and then terminating a welding power output after supplying a predetermined amount of welding current for a predetermined duration of time starting from a time when opening of the shorting occurs during the backward retraction of the welding wire.

Arc-welding method and arc-welding apparatus

In a pulse arc welding machine which is adapted to feed at a constant speed a welding wire as a waste electrode to turn the molten lump of the wire tip end into a spray state with a pulse current so as to effect a welding operation, the risetime and falltime of the pulse current influence the bead outer appearance, the gas shielding property and welding function and are varied independently of the other parameters controlled by the machine in accordance with the material quality of the welding wire, the wire diameter, and the wire feeding speed.

Pulsed arc welding machine

PURPOSE: To suppress spatters generated due to arc running-out at the time of starting welding by instructing an output current waveform of short circuiting transfer welding in a specified time limit from the welding start and instructing a pulsative output current waveform after a specified time limit. CONSTITUTION: A signal ST of a timer 4 is outputted at a low level in a specified time limit from the welding start. A changeover element part 3 selects a first signal S1 outputted from a short circuit transfer welding instruction part 1 to instruct the current waveform of short circuiting transfer welding and outputs a third signal S3 to a driving circuit part 5 so that a welding wire coming into contact and short-circuiting with base metals or arc generation is carried out repeatedly alternately. When a specified time elapses after welding is started, the timer 4 is operated and the timer signal ST is converted into a high level. The changeover element part 3 selects a second signal S2 outputted from a pulse welding instruction part 2 to instruct the pulsative current waveform to perform spray transfer welding and outputs the third signal S3 to the driving circuit part 5. COPYRIGHT: (C)1991,JPO&Japio

Pulse arc welding machine

PURPOSE: To prevent infiltration of electromagnetic noise and to improve workability by receiving a signal from a remote controller to set a welding output condition by a wireless and transmitting a welding output set value to a welding power source. CONSTITUTION: The welding output condition is converted into a first electric transmission signal ESI by an output condition signal setting part 6 of the remote controller 3 and ESI is converted into an infrared light signal IFRs and outputted by an infrared output part 7. An infrared photodetection part 5 of a signal receiving part 2 converts the infrared light signal IFRS received into a second electric transmission signal ES2 which is converted into a welding output setting signal DS by a welding output setting signal conversion part 4 and outputted to the welding power source 1 and the welding output condition is set. Since the signal transmission between the remote controller 3 and the signal receiving part 2 is carried out without using an electric signal line cable, the problem caused by using the cable, namely, the cable being caught during work and the problem of electromagnetic noise are prevented. COPYRIGHT: (C)1991,JPO&Japio

Masahiro Minooka

Papers

Pulsed arc welding machine

Pulse arc welding machine

Remote control type welding power unit