JPS6320172A - Power source of pulse arc welding - Google Patents

Abstract

PURPOSE:To perform the stable welding by comparing an average voltage signal from an average voltage circuit with a set signal from an output voltage setter to adjust a base time setting signal according to a difference between both the signals and preventing an arc from running out and instability of the arc. CONSTITUTION:AC input 1 is converted into a DC by a rectifier circuit 31 and afterward, converted into the pulse electric power for arc-welding with a pulse output part 32 and supplied to between a welding electrode 13 and base metal 10. A pulse wave-form is determined by a peak voltage signal VP, a base voltage signal VB, a peak time signal TP and a base time signal TB with a wave-form control circuit 33 and its output is inputted to the pulse output part 32. The average voltage circuit 34 produces the average voltage signal corresponding to the average voltage which is supplied to between the welding electrode 13 and the base metal 10 by a signal from the wave-form control circuit 33 and inputs it to a base time setting circuit 27. The average voltage signal is compared to the signal from the output voltage setter 20 with the base time setting circuit 27 to adjust the base time setting signal TB according to a differential signal between both the signals.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a power supply for a pulse arc welding machine, and more specifically, it converts AC input into DC and further converts it into a switching output control element such as a transistor. Yo Shisui.

The present invention relates to a long-term welding power source that alternately supplies high-voltage pulse output and low-voltage output between a welding electrode and a base metal by controlling the pitch. 1゜ [Prior art] □ In pulse arc welding, high voltage pulse output (referred to as peak voltage vP) and low voltage output (hereinafter referred to as peak voltage VB) are used.
) is alternately supplied between the welding electrode and the base metal to carry out welding.・3. .

Traditional pulsed arc welding uses a high-capacity switching control to switch the rectified direct current.

direct pulsed arc melting.

When obtaining contact force, the lid is relatively small and operates at high speed.

The rectified direct current is converted into a plurality of continuous and alternating pulse trains whose pulse width is controlled by 5 high-speed switching using switching elements, and furthermore, the

When obtaining pulse arc power output from the pulse train through a transformer and rectifier circuit (inverter type power supply).

I'm happy to be hired. The voltage waveform of pulsed arc welding output is shown in Figure 5, with peak voltage VP, base voltage V
B, peak time TP, and base time Ta1c. (% Kaisho 60 = Publication No. 234773).

[Problems to be solved by the invention] 1. The conventional pulsed arc welding power source described above does not perform welding.

Before starting the work, the worker should operate the adjustment knobs etc. and beep.

The values of the welding voltage vP, peak time Tl+, and base voltage Vasbase time TB, which can be determined from welding conditions such as the materials of the base metal and welding electrode and the feed speed of the welding electrode, are determined from data tables and experimental results. I had made up my mind. Peak voltage VP and base voltage VB.

Suitable for controlling to a predetermined constant voltage.

In addition, the average voltage VA of the pulsed arc power supply output is specified.

It is necessary to set the voltage to a constant voltage. Average voltage 1VA
This is due to fluctuations in AC input power and camera shake during welding.

This compensates for the fluctuation caused by the pulse arc and generates a stable pulse arc.

It is effective to achieve this. Therefore, the amount of welding work.

First, welding current, or welding electrode (hereinafter simply Wa).

The feeding speed and average voltage (referred to as "I") are set in advance. After setting the welding current and average voltage, peak voltage Vp, peak time TP% base voltage/voltage V
p, newly set or change the base time TB.

, and the average voltage Vm will also change accordingly,
It is difficult to adjust the pulse voltage. That is, by changing the Norls voltage waveform, the size of the droplet.

Adjust the number of droplets, etc. (change the transfer form of droplets).

However, if the average voltage changes at this time, the half-average arc length changes, resulting in arc breakage or arcing.

This could cause instability. 2゜The present invention eliminates the above-mentioned conventional drawbacks, makes it easy to adjust pulse arc welding conditions, and eliminates arc breakage.

Pulsed arc welding electrode that eliminates arc instability.

The purpose is to provide

[Means to solve the problem] 5.1
The figure shows the pulsed arc welding power source of the present invention.

This is a lock diagram. In the figure, l is AC power, 31' is a rectifier circuit, and 32 is a pulse output section, and its output end is.

A welding electrode 13 is connected to the base material 10. 33° is a waveform control circuit, which includes a peak voltage setter 17, a peak voltage setter 16, and a base voltage setter 18. and page.

is connected to the time setting device 27. Base time setting.

An average voltage circuit 34 is connected to the circuit 27 so as to provide negative feedback with respect to the waveform control circuit 3.3.゛[Function] 1゜AC human power l was converted into DC by the rectifier circuit 31.

Pulse power for arc welding is provided at the rear pulse output portion 32.

and is supplied between the welding electrode 13 and the base material 10.

be provided. The pulse waveform is pulsed by the waveform control circuit 33.

voltage signal VP, base voltage signal VB, peak time signal.

TP, determined by the base time signal TB and its output.

The force is input to the pulse output section 32. Average voltage circuit 34
Now, the signal from the waveform control circuit 33 is the welding electrode 1.
3 and the base material 10.

An average voltage signal corresponding to the voltage is created and input to the base time 5 setting circuit 27. The average voltage signal is B.

from the output voltage setting device 2o at the time setting circuit 27.

signal. In the base time setting circuit 27.

adjusts the base time correlation setting signal Ta according to the difference signal obtained as a result of the comparison. 0 [Embodiment] FIG. 2 is a diagram showing an embodiment of the present invention, in which the same reference numerals as in FIG. 1 indicate the same parts. 3 is a smoothing capacitor connected in parallel to the output end of the rectifier circuit 2.

The transformer 4 is an inverter main circuit which performs switching control and is controlled by the circuit 14, and further applies a high circumferential alternating voltage to the transformer 5. 6 is a rectifier and is a DC reactor.

Welding power is applied between the wire 13 and the base material 10 via the luer. During welding, the welding current is determined in relation to the feeding speed of the wire 13, so it is recommended to use the following method.

The feed setting device 12 feeds the wire 13 at a constant speed.

It has become. The welding voltage is passed through a comparator 27 (base time setting device 27) by an output voltage setting device 20°.

and input it to the pattern generator 15 to generate a peak.

Signals from each pulse waveform setter shown as time setter 16, peak voltage setter 17, and base voltage setter 18.

Together, the pulse waveform shown in FIG. 5 is generated.

By outputting a signal for p to the switching control circuit 14, a desired pulse voltage is generated. The details of the pulse generator 15 are shown in FIG. 3, including an adder and an inverting amplifier circuit 56,57 including 10 analog switches 51, 52, an oscillator 53, an in-bark 54, and a resistor 54,55.
It consists of In this pattern generator 15,
If the output (signal) 19 of the base time setter 27 becomes high, the base time TB becomes short, that is, the average value of the output voltage becomes high.

Become. Conversely, if the output 19 becomes low, the base time Tnf)p
In other words, the average value of the output voltage becomes low. The base time setting device 27 is supplied with a voltage obtained by integrating the output voltage of the voltage detection circuit 23 that detects the voltage fluctuation of the AC human power 1 via the analog switch 25 with the integrator 26 .

Pressure is applied. The voltage detection circuit 23 is shown in FIG.

As shown, transformer 61. Rectifier circuit 62, integrator.

It will be done. The switching control circuit 14 has a sawtooth waveform.

oscillator (not shown) known in the art.

Pattern generator with inverter drive circuit.

15 and a sawtooth signal having a predetermined frequency.

Switching is performed based on the result of determining whether the signal is large or small.

Drive the element. (Refer to Japanese Unexamined Patent Publication No. 60-234773.) Since the driving signal of the switching element corresponds to the pulse voltage waveform shown in Fig. 5 (the frequency is sufficiently high to 1-), the average value of this pulse voltage versus.

respond.

Note that the oscillator 53 is activated at the peak time TP and at the base time.

A square wave signal generator that alternates between TB and TB, a combination of two one-shot multis, or a combination of two shift registers, or a clock oscillator and power.

Adjustable with counter combination or sawtooth oscillator.

Depending on the combination of the DC voltage source and comparison circuit, etc., the time TP'
This allows the TB to be controlled appropriately.

In this embodiment using an inverter type power source, the average value of the output voltage is proportional to the pulse time ratio (duty) of the output of the inverter main circuit 4, so it is a product.

The output voltage of the divider 26 has a proportional relationship to the average value of the welding voltage. Therefore, the output voltage of the integrator 26 is expressed as

The output voltage is input to the time setting device 27 and compared with the output from the output voltage setting device 2010, and the result is set as the base time signal TB. Furthermore, since voltage fluctuations in the power source 1 directly cause fluctuations in the average value of the output voltage, the voltage detection circuit is also required.

Although line 23 was used, power supply voltage fluctuations are allowed.

In this case, the voltage detection circuit 23 is simply a stabilized power supply, etc. I71!
−.

It can also be a voltage source.

In the above embodiments, the arc voltage is directly fed back negatively.

Since there is no magnetic blow, it is possible to provide a stable power supply that is not affected by welding (phenomena) such as unstable wire feeding, etc. During welding work, the peak time TP% 2 (1 peak voltage Vp, base voltage Arc welding machine because the appropriate base time TB is set even if Va is reset.

This has the advantage that it is easy to operate.

〔effect〕

As described above, according to the present invention, arc breakage and arc instability are eliminated in pulsed arc welding, and stable welding can be performed.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the present invention, and FIG. 2 is a more detailed circuit diagram of the present invention. 3 is a partial circuit configuration diagram of FIG. 2, and FIG. 4 is a specific circuit diagram of the voltage detection circuit in FIG. 2. FIG. 5 is a voltage waveform diagram used in pulsed arc welding. 1... AC input, 31... Rectifier circuit, 32.
... Pa. pulse output section, 33... waveform control circuit, 34...
! Average voltage circuit, 10... Base material, 13...
Welding electrode, 20... Output voltage setting device, 27
...Base time setting device.ゝ・Deno Procedures Amendment (Method) Showa 6k 1
October 24th

Claims (1)

[Claims] A rectifier circuit converts AC input into DC output, and the DC output of this rectifier circuit is controlled by switching using a switching output control element such as a transistor, and high voltage output and low voltage output are alternately output between the welding electrode and the base material. A pulsed arc welding power source consisting of a pulse output section, an output voltage setting device for setting the average voltage supplied between the welding electrode and the base metal, and a peak voltage V_ when outputting the high voltage.
A peak voltage setting signal for setting P, a peak time setting signal for setting the peak time T_P at the time of this high voltage output,
The base voltage setting signal that sets the base voltage V_B at the time of the above low voltage output and the base time T_B at the time of this low voltage output
a waveform control circuit that controls the switching output control element by a base time setting signal that sets a peak and base voltage setting signal and a peak and base time setting signal that is supplied between the welding electrode and the base metal. An average voltage circuit generates a signal corresponding to the average voltage to be output, and the average voltage signal from this average voltage circuit is compared with the setting signal from the output voltage setting device, and the base time is set according to the difference between the two signals. A pulsed arc welding power source comprising a base time setting circuit for adjusting a signal.