JP2000015440A - Arc loading device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously vary a pseudo-arc voltage by inputting a difference between output signals of a voltage detector in a power source and arc voltage setting signals obtained with an arithmetic circuit from current detecting signals of the power source, feed speed setting signals of a consumable electrode and tip distance setting signals and providing between output terminals of the power source with an analog element whose conducting quantity varies in proportion to the input. SOLUTION: In an arc voltage setting signal arithmetic circuit 16, arc voltage setting signals Vr is obtained as a function of current detecting signals If of a DC arc welding power source 1, feed speed setting signals S1 of a consumable electrode and tip distance setting signals S2 equivalent to a distance between a tip end sending the consumable electrode and a workpiece and outputted. A pseudo arc circuit 19 is composed of a comparator 21, a resistor 22 and a transistor 23 which output differential signals (ΔV=Vf-Vr) by comparing output signals Vf of a voltage detector 20 which is connected between terminals Tm7, Tm8 respectively connected to output terminals of the power source 1 with the arc voltage setting signals Vr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arc load device which is connected to an output terminal of a power supply device used for consumable electrode type arc welding to measure an output characteristic of the power supply device by simulating an arc voltage. It is about improvement.

[0002]

2. Description of the Related Art FIG. 12 is a view showing a state in which arc welding is performed using a general consumable electrode. A tip 10 and a work piece are connected to output terminals Tm1 and Tm2 of a power supply device 1 for DC arc welding. The objects 4 are connected to each other, pulled out from the wire reel 8, and fed by the feed roller 9 to the chip 10.
Consumable electrode (hereinafter referred to as wire) 3 fed through
An arc 5 is generated between the tip of the workpiece 4 and the workpiece 4. Reference numeral 2 denotes an output setting device connected to the input terminals Tm5 and Tm6, which sets an output current when the power supply device 1 has a constant current characteristic, and sets an output voltage when the power supply device 1 has a constant voltage characteristic. . Here, the tip 10, the wire 3, the arc 5, and the workpiece 4 constitute an arc load. When the characteristic test of the power supply device 1 is performed, for each of the cases where the output setting device 2 is changed, a voltage drop Va equivalent to the arc voltage is generated, and the voltage is changed to perform the characteristic test. ing. Since the voltage-current characteristics of the arc discharge used for arc welding are almost constant voltage characteristics, the load device shown in FIG. 13 or FIG. 14 is conventionally used. In FIG. 13, the diode 6
Utilizing the characteristic that the forward voltage-current characteristic is almost constant voltage, the number of diodes 6 is adjusted to generate a voltage drop equivalent to a pseudo arc voltage. In FIG. 14, a voltage drop equivalent to a pseudo arc voltage is generated by adjusting the number of batteries 7.

[0003]

In the conventional apparatus shown in FIGS. 13 and 14, the only way to adjust the simulated arc voltage is to change the number of diodes 6 or batteries 7. Cannot be changed continuously. Further, in order to change the arc voltage, it is necessary to change the number of connected diodes 6 or batteries 7 each time, and cannot be changed by an external signal. For this reason, there is a problem that it is difficult to adjust the arc voltage.

[0004]

An arc load device according to the present invention is connected to an output terminal of a power supply device used for consumable electrode type arc welding and used to measure an output characteristic of the power supply device. In the apparatus, a voltage detector connected between output terminals of the power supply, a current detection signal (If) of the power supply, and a supply speed setting signal (S1) of the consumable electrode.
An arc voltage setting signal calculation circuit for obtaining an arc voltage setting signal (Vr) as a function of a tip distance setting signal (S2) corresponding to a distance between the tip of the tip that sends out the consumable electrode and the workpiece; An output terminal of a power supply device in which a difference (ΔV = Vf−Vr) between an output signal (Vf) of a voltage detector and an output signal (Vr) of an arc voltage setting signal calculation circuit is input and a conduction amount changes in proportion to the input. An arc load device having an analog element connected between the two is proposed.

According to a second aspect of the present invention, there is provided an arc load device which is connected to an output terminal of a power supply device used for consumable electrode type arc welding and used for measuring output characteristics of the power supply device. A capacitor connected between the output terminals, a voltage detector connected to both terminals of the capacitor, a current detection signal (If) of the power supply, a feed rate setting signal (S1) for the consumable electrode, and a consumable electrode An arc voltage setting signal calculation circuit for obtaining an arc voltage setting signal (Vr) as a function of a tip distance setting signal (S2) corresponding to the distance between the tip of the tip sending out the workpiece and the workpiece; With a difference (ΔV = Vf−Vr) between the output signal (Vf) and the output signal (Vr) of the arc voltage setting signal calculation circuit as an input, a pulse having a conduction time ratio proportional to the input is generated at a predetermined frequency. A pulse generator, a switching element which is conducting controlled by the output pulse of the pulse generator, in which the power supplied from the capacitor proposed an arc load device provided with a resistor which is adjusted by conduction of the switching element.

According to a third aspect of the present invention, the arc load device includes a current detection signal (If) as an arc voltage setting signal calculation circuit.
And the feed speed setting signal (S1) and the chip distance setting signal (S1).
2), an arc length setting signal (S3) corresponding to the distance between the tip of the consumable electrode and the workpiece is given by S3 = S2-Lex (where dLex / dt = S1-Vm Vm = K1 × If + K2 × If ² × Lex addition, Vr and arc length calculation circuit for calculating by the K1 and K2 constants), the current detection signal (If) and arc voltage setting signal and the arc length setting signal (S3) as input (Vr) = A + B × If + (C + D × If) × S3 (where A, B, C, and D are constants), and an arc voltage calculation circuit is provided. Things.

According to a fourth aspect of the present invention, there is provided an arc load device which is connected to an output terminal of a power supply device used for consumable electrode type AC arc welding and is used for measuring output characteristics of the power supply device. A first phase-locked loop that takes in the positive half-wave of the output voltage of the input voltage and takes out the voltage after the re-ignition phase, a first voltage detector connected between the output terminals of the first phase-locked loop, A second phase-locked loop that takes in the negative half-wave of the output voltage as an input and extracts a voltage after the re-ignition phase, a second voltage detector connected between the output terminals of the second phase-locked loop, The first detection signal (Ifa) of the positive half-wave of the output current, the feed rate setting signal (S1) for the consumable electrode, and the distance between the tip of the tip for sending the consumable electrode and the workpiece. Chip distance setting signal (S
2) the first arc voltage setting signal (Vra) as a function of
, A second detection signal (Ifb) of the negative half-wave of the output current of the power supply device, a supply speed setting signal (S1) for the consumable electrode, and a chip distance setting signal (S2). ) As a function of the second arc voltage setting signal (V
rb), and the difference (ΔVa = Vfa−Vra) between the output signal (Vfa) of the first voltage detector and the first arc voltage setting signal (Vra) is input to the input. A first analog element connected between output terminals of a first phase-locked loop whose conduction amount changes proportionally,
The difference between the output signal (Vfb) of the second voltage detector and the second arc voltage setting signal (Vrb) (ΔVb = Vfb−Vrb)
And the second analog element connected between the output terminals of the second phase-locked loop whose conduction amount changes in proportion to the input.

According to a fifth aspect of the present invention, there is provided an arc load device which is connected to an output terminal of a power supply device used for consumable electrode type AC arc welding and is used for measuring output characteristics of the power supply device. A first phase-locked loop that takes in the positive half-wave of the output voltage as an input and extracts the voltage after the re-ignition phase, a first capacitor connected between the output terminals of the first phase-locked loop, A first voltage detector connected to both terminals, a second phase-locked loop that takes in a negative half-wave of the output voltage of the power supply as input and extracts a voltage after the re-ignition phase, and an output terminal of the second phase-locked loop , A second voltage detector connected to both terminals of the second capacitor, a first detection signal (Ifa) of a positive half-wave of an output current of the power supply, and a consumable electrode. Feed speed setting signal (S1) The first arc voltage setting signal as a function of the chip length setting signal corresponding to the distance between the tip and the workpiece chip delivering consumable electrode (S2) (Vr
a first arc voltage setting signal calculation circuit for obtaining a), a second detection signal (Ifb) of a negative half wave of the output current of the power supply device, a supply speed setting signal (S1) for the consumable electrode, and a chip distance setting signal A second arc voltage setting signal calculation circuit for obtaining a second arc voltage setting signal (Vrb) as a function of (S2), an output signal (Vfa) of the first voltage detector, and a first arc voltage setting signal (Vra). (ΔVa = Vfa−Vr)
a) a first pulse generator that generates a pulse having a conduction time ratio proportional to the input at a predetermined frequency with a) as an input, a first switching element controlled to be conductive by an output pulse of the first pulse generator, and a first switching element And the difference between the output signal (Vfb) of the second voltage detector and the second arc voltage setting signal (Vrb) (ΔVb = Vfb−Vrb). ), A second pulse generator that generates a pulse having a conduction time ratio proportional to the input at a predetermined frequency, a second switching element that is conduction controlled by an output pulse of the second pulse generator, and a second switching element. And a second resistor in which the power supplied from the second capacitor is adjusted by the conduction of the second capacitor.

[0009] The arc load device according to claim 6 is a first load device.
As an arc voltage setting signal calculation circuit, a first current detection signal (Ifa), a feed speed setting signal (S1), and a tip distance setting signal (S2) are input and a circuit is provided between the tip of the consumable electrode and the workpiece. The first arc length setting signal (S
3a) The S3a = S2-Lexa (however, dLexa / dt = S1-Vma Vma = K1a × Ifa + K2a × Ifa 2 × Lexa Further, K1a and K2a are a first arc length calculation circuit for calculating the constants), the first current The detection signal (Ifa) and the first arc length setting signal (S3a) are input and the first arc voltage setting signal (Vra) is converted into Vra = Aa + Ba × Ifa + (Ca + Da × Ifa).
.Times.S3a (where Aa, Ba, Ca, and Da are constants), and a second arc voltage setting signal calculation circuit as a second arc voltage setting signal calculation circuit.
fb), the feed speed setting signal (S1), and the tip distance setting signal (S2), the second arc length setting signal (S3) corresponding to the distance between the tip of the consumable electrode and the workpiece.
b) The S3b = S2-Lexb (however, dLexb / dt = S1-Vmb Vmb = K1b × Ifb + K2b × Ifb 2 × Lexb Further, K1b and K2b is a second arc length calculation circuit for calculating the constant), the second current The detection signal (Ifb) and the second arc length setting signal (S3b) are input, and the second arc voltage setting signal (Vrb) is obtained as follows: Vrb = Ab + Bb × Ifb + (Cb + Db × Ifb)
5. A second arc voltage calculation circuit that calculates a value based on .times.S3b (where Ab, Bb, Cb, and Db are constants).
Or an arc load device described in 5.

[0010]

FIG. 1 is a connection diagram showing an example of an embodiment of the present invention. In the figure, reference numeral 1 denotes a power supply for DC arc welding, which is supplied with electric power from a commercial AC power supply (not shown) or the like, and is supplied to output terminals Tm1 and Tm2 by closing a start command switch TS connected to terminals Tm3 and Tm4. DC output. 2 is the input terminal T
Output setting devices connected to m5 and Tm6, 13 is a current detector, 14 is a wire feed speed setting device, and 15 is a voltage corresponding to the distance between the tip of the tip 10 and the workpiece 4. It is a chip distance setting device. 16 is an output signal S1 of the wire feed speed setting device 14 and a tip distance setting device 15
Is an arc voltage setting signal calculation circuit that outputs an arc voltage setting signal Vr by using the output signal S2 of the current detector 13 and the output signal If of the current detector 13 as inputs, and includes an arc length calculation circuit 17 and an arc voltage calculation circuit 18. The arc length calculation circuit 17 is connected to the wire feed speed setting device 1 from the input terminal Tm15.
4 and the output signal S2 of the chip distance setting device 15 from the input terminal Tm16.
The output signal If of the current detector 13 is input from m14,
The distance between the tip of the wire 3 and the workpiece 4 is calculated, and a signal S3 is output from the output terminal Tm13. The arc voltage calculation circuit 18 receives the output signal If of the current detector 13 from the input terminal Tm11, receives the output signal S3 of the arc length calculation circuit 17 from the input terminal Tm12, calculates the arc voltage, and calculates the output voltage. Arc voltage setting signal V from Tm10
Output r. Reference numeral 19 denotes a simulated arc circuit, in which input terminals Tm7 and Tm8 are connected to output terminals Tm1 and Tm2 of the power supply device 1 for DC arc welding, respectively, and a voltage detector 20 connected between the input terminals Tm7 and Tm8.
The output signal Vr of the arc voltage setting signal calculation circuit 16 and the output signal V of the voltage detector 20 input from the input terminal Tm9
The comparator 21 outputs a difference signal ΔV = Vf−Vr by comparing the signal f with the signal f, a resistor 22, and a transistor 23. Wire feed speed setting device 14 and tip distance setting device 1
5, the arc voltage setting signal operation circuit 16 and the pseudo arc circuit 19 constitute the arc load device of the present invention.

In FIG. 1, the output signal Vr of the arc voltage setting signal calculation circuit 16 and the output signal Vf of the voltage detector 20 are shown.
The amount of conduction of the transistor 23 changes until the values become equal. Therefore, when the output signal of the arc voltage setting signal calculation circuit 16 increases, the base current of the transistor 23 decreases, the conduction amount of the transistor 23 decreases, and the output current of the power supply device 1 for DC arc welding is reduced. Thus, the voltage between the output terminals Tm1 and Tm2 increases, and the arc voltage increases. Conversely, when the output signal of the arc voltage setting signal calculation circuit 16 drops, the base current of the transistor 23 increases, and the conduction amount of the transistor 23 increases. As a result, the voltage between the output terminals Tm1 and Tm2 of the power supply device 1 for DC arc welding decreases,
The arc voltage will drop.

Here, the operation contents of the arc voltage operation circuit 16 will be examined. Change in protrusion length dL of wire 3
ex / dt is the difference between the feed speed S1 of the wire 3 and the melting speed Vm of the wire 3, and can be expressed as dLex / dt = S1-Vm (1). Also, the melting speed Vm of the wire 3
Is the sum of the melting amount in the arc 5 proportional to the first power of the arc current If and the melting amount in the protrusion length Lex of the wire 3 proportional to the square of the arc current If. if, can be expressed by Vm = K1 × if + K2 × if 2 × Lex ... (2). Further, the distance S3 between the tip of the wire 3 and the workpiece 4, that is, the arc length, is the difference between the distance S2 between the tip of the tip 10 and the workpiece 4 and the protrusion length Lex of the wire 3. , S3 = S2-Lex (3).

Next, the relationship between the arc voltage Va and the current Ia will be described with reference to FIG. FIG. 2 is a diagram showing a relationship between the arc voltage Va and the current Ia using a distance (wire distance) L between the wire 3 and the workpiece 4 as a parameter. In the figure, the wire distance L is L1 <L2 <L3
This relationship is expressed by the following equation (4), where A, B, C, and D are constants. Va = A + B × Ia + (C + D × Ia) × L (4) Therefore, the arc length calculation circuit 17 of the arc voltage setting signal calculation circuit 16 determines the set value S1 of the wire feed speed setting device 14.
And the set value S2 of the tip distance setting device 15 are input, the above equations (1) to (3) are operated to obtain a signal S3. The arc voltage operation circuit 18 is an arc length operation circuit 1
7 and the detected value If of the current detector 13 as inputs, Va = Vr and Ia = I in the above equation (4).
f, L = S3, Vr = A + B × If + (C + D ×
A circuit for obtaining If) × S3 may be used.

FIG. 3 is a diagram showing an embodiment of an arc length calculating circuit 17 corresponding to the distance between the tip of the wire 3 and the workpiece 4 by calculating the above equations in the embodiment of FIG. In the figure, 66 and 69 are multipliers, 67 and 6
8 is a proportional calculator, 70 and 72 are adders, and 71 is an integrator. Multiplier 66 outputs the If ^2, proportional calculator 67 is multiplied by a coefficient K2 to, and outputs the K2 × the If ^2. The proportional calculator 68 multiplies the input signal If by the coefficient K1 to output K1 × If, and the adder 70 outputs S1− (K1
× If + K2 × If ² × Lex) and outputs the result to the integrator 71.
Integrates this to obtain ∫ (S1−K1 × If−K2 × If
² × Lex) dt = Lex is output. The adder 72
A difference signal S3 = S2-Lex is output from the tip distance setting signal S2 and the output Lex of the integrator 71 as an arc length setting signal S3.

FIG. 4 is a diagram showing an embodiment of the arc voltage calculation circuit 18 used in the embodiment of FIG. In the figure,
48, 51 and 53 are multipliers, 49, 50 and 5
Reference numeral 2 denotes an adder, and reference numerals 54 to 57 denote voltage setting units, which set voltages corresponding to the constants A to D in the above-described equation (4) and output constants a to d corresponding to these voltages, respectively. In the figure, the output signal Vr is as follows. Vr = a + b × If + (c + d × If) × S3 (5) where, Vr: arc voltage setting signal (corresponding to arc voltage Va in FIG. 2) If: output signal of current detector 13 (current Ia in FIG. 2) S3: output signal of arc length calculation circuit 17 (corresponding to wire distance L in FIG. 2) a, b, c, d: constants corresponding to constants A to D in equation (4), respectively

FIG. 5 is a diagram showing another embodiment of the pseudo arc circuit 19 of the present invention. In the figure, C1 is a capacitor connected between the input terminals Tm7 and Tm8 of the pseudo arc circuit 19, 20 is a voltage detector, and 21 is an input terminal T.
A comparator that compares the output signal Vr of the arc voltage setting signal operation circuit 16 input from m9 and the output signal Vf of the voltage detector 20 and outputs a difference signal ΔV = Vf−Vr, and 24 is an output from the comparator 21 A pulse width control (PWM) circuit that outputs a pulse signal of a constant frequency at a conduction time ratio (ON duty) proportional to the difference signal ΔV, a switching transistor 25, a switching transistor DR1,
5 is a diode connected in parallel with the opposite polarity to the switching transistor 5, and is provided to prevent a reverse voltage from being applied to the switching transistor 25. Reference numeral 26 denotes a resistor from which the value stored in the capacitor C1 is discharged.

In FIG. 5, the output signal Vr of the arc voltage setting signal calculation circuit 16 and the output signal Vf of the voltage detector 20 are shown.
The ON duty of the pulse signal output from the PWM circuit 24 is changed so that Therefore, when the output signal of the arc voltage setting signal calculation circuit 16 rises, the ON duty of the pulse signal output from the PWM circuit 24 decreases, and the switching transistor 25
Becomes smaller. As a result, the discharge amount of the capacitor C1 decreases, the average voltage of the capacitor C1 increases, and the arc voltage increases. Conversely, when the output signal of the arc voltage setting signal calculation circuit 16 decreases, PW
The ON duty of the pulse signal output from the M circuit 24 increases, and the ON duty of the switching transistor 25 increases. As a result, the discharge amount of the capacitor C1 increases, the average voltage of the capacitor C1 decreases, and the arc voltage decreases.

FIG. 6 is a diagram showing still another embodiment of the pseudo arc circuit 19 of the present invention. In the figure, C1 is a capacitor connected between the input terminals Tm7 and Tm8 of the pseudo arc circuit 19, 20 is a voltage detector, 21 is an output signal of the arc voltage setting signal calculation circuit 16 input from the input terminal Tm9. A comparator that compares Vr with the output signal Vf of the voltage detector 20 and outputs a difference signal ΔV = Vf−Vr;
27 is an ON duty proportional to the difference signal ΔV output from the comparator 21, and pulse signals P1 and P having a constant frequency with an ON duty.
Pulse width control (PWM) circuit for alternately outputting 2; 28
And 31 are bridge-connected switching elements, 3
Diodes 2 to 35 are connected in parallel with the opposite polarities of the switching elements 28 to 31, respectively, and are provided in order to prevent application of a reverse voltage to the switching elements 28 to 31. Switching element 28
To 31 and diodes 32 to 35 constitute an inverter circuit 36. 37 is an output transformer,
The output voltage of the inverter circuit 36 is converted. 38 is a resistor.

In FIG. 6, the output signal Vr of the arc voltage setting signal calculation circuit 16 and the output signal Vf of the voltage detector 20 are shown.
The ON duties of the pulse signals P1 and P2 output from the PWM circuit 27 are changed such that are equal. Therefore, when the output signal of the arc voltage setting signal calculation circuit 16 increases, the ON duty of the pulse signals P1 and P2 output from the PWM circuit 27 decreases, and the ON duty of the inverter circuit 36 decreases. As a result, the discharge amount of the capacitor C1 decreases, the average voltage of the capacitor C1 increases, and the arc voltage increases. Conversely, when the output signal of the arc voltage setting signal calculation circuit 16 decreases, the ON duty of the pulse signals P1 and P2 output from the PWM circuit 27 increases, and the ON duty of the inverter circuit 36 increases. As a result, the discharge amount of the capacitor C1 increases and the capacitor C1
And the arc voltage decreases.

FIG. 7 is a diagram showing still another embodiment of the pseudo arc circuit 19 of the present invention. In the figure, C1 is a capacitor connected between the input terminals Tm7 and Tm8 of the pseudo arc circuit 19, 20 is a voltage detector, 21 is an output signal of the arc voltage setting signal calculation circuit 16 input from the input terminal Tm9. A comparator that compares Vr with the output signal Vf of the voltage detector 20 and outputs a difference signal ΔV = Vf−Vr;
45 is a pulse width control (PWM) circuit that outputs a pulse signal of a constant frequency with an ON duty proportional to the difference signal ΔV output from the comparator 21; 40 is a switching transistor; These are connected diodes and are provided to prevent a reverse voltage from being applied to the switching transistor 40. 39 is a reactor, 42 is a diode, and 43 is a resistor. Transistor 40 is O
The electromagnetic energy stored in the reactor 39 during N is released through the resistor 43 while the transistor 40 is off.

In FIG. 7, the output signal Vr of the arc voltage setting signal calculation circuit 16 and the output signal Vf of the voltage detector 20 are shown.
The ON duty of the pulse signal output from the PWM circuit 45 is changed so that Therefore, when the output signal of the arc voltage setting signal calculation circuit 16 rises, the ON duty of the pulse signal output from the PWM circuit 45 decreases, and the switching transistor 40
Becomes smaller. As a result, the discharge amount of the capacitor C1 decreases, the average voltage of the capacitor C1 increases, and the arc voltage increases. Conversely, when the output signal of the arc voltage setting signal calculation circuit 16 decreases, PW
The ON duty of the pulse signal output from the M circuit 45 increases, and the ON duty of the switching transistor 40 increases. As a result, the discharge amount of the capacitor C1 increases, the average voltage of the capacitor C1 decreases, and the arc voltage decreases.

FIG. 8 is a diagram showing still another embodiment of the pseudo arc circuit 19 of the present invention. 7, reference numeral 44 denotes an output transformer, which is provided in place of the reactor 39 shown in FIG. 7, and the other components having the same functions as those in FIG. The operation is described in FIG.
The description of the operation of the embodiment shown in FIG.

In the embodiment shown in FIGS. 1 to 8,
The arc length calculation circuit 17 outputs the output signal I of the current detector 13.
f, the output signal S1 of the wire feed speed setting device 14 and the output signal S2 of the tip distance setting device 15 are inputted, and the above-described equations (1) to (3) are operated to calculate the tip of the wire 3. A distance setting signal S3 between the workpiece and the workpiece 4 is output.
The arc voltage operation circuit 18 receives the output signal If of the current detector 13 and the output signal S3 of the arc length operation circuit 17 and performs the operation of the above-described equation (5) to obtain an arc voltage directly proportional to the arc current. The setting signal Vr is output. As a result, when the output signal S1 of the wire feed speed setting device 14 is increased, the arc voltage setting signal Vr is decreased, and when the signal S1 is decreased, the signal Vr is increased. When the output signal S2 of the chip distance setting device 15 is increased, the arc voltage setting signal Vr is increased, and when the signal S2 is decreased, the signal Vr is decreased. The pseudo arc load circuit 19 receives the arc voltage setting signal Vr and controls the same so as to be equal to the output signal Vr of the voltage detector 20. As a result, the dynamic characteristics of the welding power source 1 can be known.

In the embodiment shown in FIG. 1, an example is shown in which a power supply device for DC arc welding is used. However, when the present invention is applied to a power supply device for AC arc welding, its output is rectified. After that, if the device shown in FIG. 1 is applied, the operation is the same.

The arc length calculating circuit 17 of the present invention shown in FIG. 3 and the arc voltage calculating circuit 18 of the present invention shown in FIG. 4 may be constituted by using a microprocessor or a digital signal processor.

In AC MIG arc welding and the like, the melting speed of the wire differs depending on the polarity of the wire. Even if the wire feeding speed is set to the same value when the wire is a positive electrode and when the wire is a negative electrode, the arc voltage is not changed. Since a difference occurs, the load voltage Vr differs depending on the polarity. For this reason, the single arc voltage setting signal operation circuit 16 as shown in FIG. 1 may not be sufficient.

FIG. 9 is a diagram showing an example of still another embodiment of the present invention which has solved this point. In FIG.
Reference numeral 6 denotes a power supply for AC arc welding having a drooping characteristic or a constant voltage characteristic. The output setter 2 is connected to input terminals Tm25 and Tm26, supplied with power from a commercial AC power supply (not shown), and connected to terminals Tm23 and Tm24. By closing the connected start command switch TS, the output terminal T
A predetermined AC output of m21 and Tm22 is generated. 5
Reference numeral 8a denotes a first phase locked loop circuit shown in the embodiment of FIG. 10 to be described later, which receives a positive half-wave of the AC arc welding power supply 46 as an input and extracts a voltage after the re-ignition phase. Reference numeral 19a denotes a first pseudo arc circuit, which is shown in FIGS.
The circuit of the embodiment of the pseudo arc circuit 19 shown in FIG. 13a is a first current detector for detecting a positive half-wave current of the AC arc welding power supply 46 and outputting a signal Ifa; 14 is a wire feed speed setting device; It is a chip distance setting device for setting a voltage corresponding to a distance from the object 4. Reference numeral 17a denotes a first arc length calculation circuit, which is connected to an input terminal Tm14a and a first current detector 1
3a, and the output signal S1 of the wire feed speed setting device 14 from the input terminal Tm15a.
The output signal S2 of the tip distance setting device 15 is input from the input terminal Tm16a, the distance between the tip of the wire 3 and the workpiece 4 is calculated, and the signal S3a is output from the output terminal Tm13a. As the first arc length calculation circuit 17a, the circuit of the embodiment shown in FIG. 3 can be used. Reference numeral 18a denotes a first arc voltage calculation circuit, which receives an output signal Ifa of the first current detector 13a from an input terminal Tm11a,
2a to the output signal S3a of the first arc length calculation circuit 17a
Is input, the arc voltage is calculated, and the output terminal Tm10a
Output the signal Vra to the first pseudo arc circuit 19a. As the first arc voltage calculation circuit 18a, the circuit of the embodiment shown in FIG. 4 can be used. First arc length calculation circuit 17
a and the first arc voltage calculation circuit 18a constitute a first arc voltage setting signal calculation circuit 16a.

Reference numeral 58b denotes a second phase-locked loop, 19b
Is a second pseudo arc load circuit, 13b is a second current detector,
17b is a second arc length calculation circuit, 18b is a second arc voltage calculation circuit, and 16b is a second arc voltage setting signal calculation circuit, which receives the negative half-wave of the AC arc welding power supply 46 as an input. A first phase locked loop 58a, a first pseudo arc load circuit 19a, a first current detector 13a, a first arc length calculation circuit 17a, a first arc voltage calculation circuit 18a, and a first arc voltage setting signal. The function is the same as that of the arithmetic circuit 16a, and the description is omitted.

FIG. 10 shows first and second phase synchronization circuits 58a and 58b (58 in FIG. 9) used in the embodiment of FIG.
FIG. 9 is a diagram showing an embodiment of the present invention. In the figure, reference numeral 59 denotes a diode, which inputs the output of the AC arc welding power supply 46 from the input terminals Tm17 and Tm18 and outputs a positive or negative half wave. Reference numeral 60 denotes a thyristor, and 61 denotes a voltage setting device. When a preset voltage corresponding to the voltage of the arc re-ignition phase when the polarity of the AC arc is inverted is detected, a signal is output to the thyristor 60 to make it conductive.

FIGS. 11A and 11B are diagrams showing waveforms in the embodiments of FIGS. 9 and 10, wherein FIG. 11A shows the input voltage of the AC arc welding power supply 46, FIG. 11B shows the output voltage of the power supply 46, and FIG. C) shows the arc current.

In FIGS. 9 to 11, the polarity of the output of the AC arc welding power supply 46 is inverted every half cycle, but the first and second phase-locked circuits 58a and 58
b, the positive and negative output voltages of the AC arc welding power supply 46 are changed to the first and second pseudo arc circuits 19a.
And 19b respectively. The first and second arc length calculation circuits 17a and 17b are connected to the output signal S1 of the wire feed speed setting device 14 and the tip distance setting device 1
5, a voltage signal S2 corresponding to the distance between the tip end of the chip 10 and the workpiece 4 is inputted, and the first and second voltage signals are inputted.
The current detectors 13a and 13b input the positive and negative output currents of the AC arc welding power supply device 46, respectively, and calculate the voltage corresponding to the distance between the tip of the wire 3 and the workpiece 4 in each half-wave. , Signals S3a and S3b, respectively. First and second arc voltage calculation circuits 18a and 18b receive signals S3a and S3b output from first and second arc length calculation circuits 17a and 17b, respectively, and output current detectors 13a and 13b.
b, the positive and negative output currents of the AC arc welding power supply device 46 are respectively input to calculate the arc voltage setting signals in each half-wave, and the arc voltage setting signals Vra and Vrb are converted into the first and second pseudo arcs. The signals are output to the circuits 19a and 19b, respectively, and are controlled such that the terminal voltages of the first and second pseudo arc load circuits coincide with the respective output signals.

As shown in FIG. 11B, the arc voltage pseudo-generated by these operations is delayed in phase by the reactor of the AC arc welding power supply 46, and the arc current shown in FIG. When becomes zero, the polarity is inverted. As a result, like the AC MIG arc welding method,
Dynamic characteristics of the power supply 46 which responds quickly to changes in arc current, wire feed speed and distance between the tip 10 of the tip 10 and the workpiece 4 even when the melting speed of the wire varies depending on the polarity of the wire. You can know.

[0033]

The arc load device of the present invention can continuously change the simulated arc voltage in the characteristic test of the power supply device for arc welding, and sets the arc voltage as in the conventional device. Therefore, the number of connected diodes or batteries does not need to be changed each time, and the power of the welding power supply is immediately changed in response to changes in arc current, wire feed speed, and the distance between the tip of the tip and the workpiece. Characteristics can be known.

Further, in the characteristic test of the power supply device for AC arc welding, in the AC MIG arc welding method, etc.
Even if the melting speed of the wire varies depending on the polarity of the wire, the dynamic characteristics of the welding power source are immediately responded to changes in the arc current, the wire feeding speed, and the distance between the tip of the tip 10 and the workpiece 4. You can know.

[Brief description of the drawings]

FIG. 1 is a connection diagram illustrating an example of an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between an arc voltage Va and a current Ia using a wire distance L as a parameter.

FIG. 3 is a diagram showing an embodiment of an arc length calculation circuit 17 of the present invention.

FIG. 4 is a diagram showing an embodiment of an arc voltage calculation circuit 18 of the present invention.

FIG. 5 is a diagram showing another embodiment of the pseudo arc circuit 19 of the present invention.

FIG. 6 is a diagram showing still another embodiment of the pseudo arc circuit 19 of the present invention.

FIG. 7 is a diagram showing still another embodiment of the pseudo arc circuit 19 of the present invention.

FIG. 8 is a diagram showing still another embodiment of the pseudo arc circuit 19 of the present invention.

FIG. 9 is a connection diagram showing an example of still another embodiment of the present invention.

FIG. 10 is a diagram illustrating an embodiment of a phase synchronization circuit 58 used in the embodiment of FIG. 9;

FIG. 11 is a diagram showing each waveform in the embodiment of FIGS. 9 and 10;

FIG. 12 is a diagram showing a state in which arc welding is performed using a general consumable electrode.

FIG. 13 is a diagram showing a connection diagram of an example of a conventional arc load device.

FIG. 14 is a diagram showing a connection diagram of another example of a conventional arc load device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply device for DC arc welding 2 Output setting device 3 Consumable electrode (wire) 4 Workpiece 5 Arc 6 Diode 7 Battery 8 Wire reel 9 Feeding roller 10 Chip 13 Current detector 13a First current detector 13b Second Current detector 14 Wire feed speed setting device 15 Tip distance setting device 16 Arc voltage setting signal calculation circuit 16a First arc voltage setting signal calculation circuit 16b Second arc voltage setting signal calculation circuit 17 Arc length calculation circuit 17a First arc length Operation circuit 17b Second arc length operation circuit 18 Arc voltage operation circuit 18a First arc voltage operation circuit 18b Second arc voltage operation circuit 19 Pseudo arc circuit 19a First pseudo arc circuit 19b Second pseudo arc circuit 20 Voltage detector 21 Comparison 22 resistor 23 transistor 24 pulse width control (PW ) Circuit 25 switching transistor 26 resistor 27 pulse width control (PWM) circuit 28, 29, 30, 31 switching element 32, 33, 34, 35 diode 36 inverter circuit 37 output transformer 38 resistor 39 reactor 40 switching transistor 41 42 Diode 43 Resistor 44 Output Transformer 46 AC Arc Welding Power Supply Device 48 Multiplier 49, 50 Adder 51 Multiplier 52 Adder 53 Multiplier 54, 55, 56, 57 Voltage Setter 58 Phase Synchronization Circuit 58a First Phase synchronization circuit 58b Second phase synchronization circuit 59 Diode 60 Thyristor 61 Voltage setting device 66 Multiplier 67, 68 Proportional calculator 69 Multiplier 70 Adder 71 Integrator 72 Adder

Claims (6)

[Claims] An arc load device connected to an output terminal of a power supply device used for consumable electrode type arc welding and used for measuring output characteristics of the power supply device, wherein the arc load device is connected between output terminals of the power supply device. A voltage detector, a current detection signal (If) of the power supply device, a feed speed setting signal (S1) of the consumable electrode, and a distance between a tip of a tip for sending the consumable electrode and the workpiece. The arc voltage setting signal (V) as a function of the tip distance setting signal (S2) corresponding to
r), a difference (ΔV = Vf−Vr) between an output signal (Vf) of the voltage detector and an output signal (Vr) of the arc voltage setting signal calculation circuit.
And an analog element connected between output terminals of the power supply device, the amount of conduction varying in proportion to the input. 2. An arc load device connected to an output terminal of a power supply device used for consumable electrode arc welding and used for measuring output characteristics of the power supply device, wherein the arc load device is connected between output terminals of the power supply device. And a voltage detector connected to both terminals of the capacitor, a current detection signal (If) of the power supply device, a feed speed setting signal (S1) for the consumable electrode, and the consumable electrode. The arc voltage setting signal (V) as a function of the tip distance setting signal (S2) corresponding to the distance between the tip of the tip and the workpiece.
r), a difference (ΔV = Vf−Vr) between an output signal (Vf) of the voltage detector and an output signal (Vr) of the arc voltage setting signal calculation circuit.
A pulse generator that generates a pulse having a conduction time ratio proportional to the input at a predetermined frequency as an input, a switching element whose conduction is controlled by an output pulse of the pulse generator, and a capacitor from the capacitor by conduction of the switching element. An arc load device comprising: a resistor whose supply power is adjusted. 3. The tip of the consumable electrode, wherein the arc voltage setting signal calculation circuit receives the current detection signal (If), the feed speed setting signal (S1), and the tip distance setting signal (S2) as inputs. the workpiece corresponds to the distance between the arc length setting signal (S3) to S3 = S2-Lex (however, dLex / dt = S1-Vm Vm = K1 × If + K2 × If 2 × Lex addition, K1 and K2 , An arc length calculation circuit calculated by the following formula, and the current detection signal (If) and the arc length setting signal (S3) as inputs. The arc voltage setting signal (Vr) is converted to Vr = A + B × If + (C + D × If). 3. The arc load device according to claim 1, further comprising: an arc voltage calculation circuit that calculates the voltage based on × S3 (where A, B, C, and D are constants). 4. 4. An arc load device connected to an output terminal of a power supply device used for consumable electrode type AC arc welding and used for measuring output characteristics of the power supply device, wherein a positive half of an output voltage of the power supply device is provided. A first phase-locked loop for taking out a voltage after a re-ignition phase by using a wave as an input, a first voltage detector connected between output terminals of the first phase-locked loop, and a negative output voltage of the power supply device; A second phase-locked loop for taking out the voltage after the re-ignition phase by using the half-wave as an input, a second voltage detector connected between output terminals of the second phase-locked loop, and an output current of the power supply device. Of the positive half-wave of
A detection signal (Ifa), a feed rate setting signal for the consumable electrode (S1), and a tip distance setting signal (S2) corresponding to a distance between the tip of the tip for sending the consumable electrode and the workpiece. Arc voltage setting signal (Vr) as a function of
a) a first arc voltage setting signal calculation circuit for obtaining a) and a second half-wave detection signal (If) of the output current of the power supply device.
b) a second arc voltage setting signal calculation circuit for obtaining a second arc voltage setting signal (Vrb) as a function of the feed rate setting signal (S1) of the consumable electrode and the tip distance setting signal (S2); The output signal of the first voltage detector (Vf
a) and the difference between the first arc voltage setting signal (Vra) (ΔVa = Vfa−Vra) is input, and is connected between the output terminals of the first phase locked loop circuit whose conduction amount changes in proportion to the input. And the difference (ΔVb = Vfb−Vrb) between the output signal (Vfb) of the second voltage detector and the second arc voltage setting signal (Vrb), and the amount of conduction in proportion to the input. And a second analog element connected between the output terminals of the second phase-locked loop. 5. An arc load device connected to an output terminal of a power supply device used for consumable electrode type AC arc welding and used for measuring output characteristics of the power supply device, wherein a positive half of an output voltage of the power supply device is provided. A first phase-locked loop for taking out a voltage after a re-ignition phase by using a wave as an input, a first capacitor connected between output terminals of the first phase-locked loop, and both terminals of the first capacitor; A first voltage detector, a second phase-locked loop that takes in the negative half-wave of the output voltage of the power supply as an input and extracts a voltage after the re-ignition phase, and an output terminal of the second phase-locked loop. A second capacitor connected thereto, a second voltage detector connected to both terminals of the second capacitor, a first detection signal (Ifa) of a positive half-wave of an output current of the power supply device, and the consumable electrode Feed speed setting signal (S1 ) And a first arc voltage setting signal (Vra) for obtaining a first arc voltage setting signal (Vra) as a function of a tip distance setting signal (S2) corresponding to the distance between the tip of the tip that sends out the consumable electrode and the workpiece. A setting signal calculation circuit, a second detection signal (Ifb) of a negative half wave of the output current of the power supply device, and a supply speed setting signal (S
1) and a second arc voltage setting signal calculation circuit for obtaining a second arc voltage setting signal (Vrb) as a function of the chip distance setting signal (S2); an output signal (Vfa) of the first voltage detector; First arc voltage setting signal (Vra)
A first pulse generator that generates a pulse having a conduction time ratio proportional to the input at a predetermined frequency with a difference (ΔVa = Vfa−Vra) as an input, and a second pulse generator that is controlled to be conductive by an output pulse of the first pulse generator. A first switching element, a first resistor whose supply power from the first capacitor is adjusted by conduction of the first switching element, an output signal (Vfb) of the second voltage detector, and a setting of the second arc voltage A second pulse generator that receives a difference (ΔVb = Vfb−Vrb) from the signal (Vrb) and generates a pulse having a conduction time ratio proportional to the input at a predetermined frequency; and an output pulse of the second pulse generator. An arc load comprising: a second switching element whose conduction is controlled; and a second resistor whose power supplied from the second capacitor is adjusted by conduction of the second switching element. Loading equipment. 6. The first arc voltage setting signal operation circuit receives the first current detection signal (Ifa), the feed speed setting signal (S1), and the tip distance setting signal (S2) and receives the consumption. S3a = S2-Lexa (where dLexa / dt = S1-Vma Vma = K1a × Ifa + K2a × Ifa ² ×) Lexa Further, a first arc length calculation circuit that calculates by K1a and K2a are constants, the first current detection signal (Ifa) and the first arc length setting signal (Sfa).
3a) and the first arc voltage setting signal (Vr)
a) Vra = Aa + Ba × Ifa + (Ca + Da × Ifa)
.Times.S3a (where Aa, Ba, Ca and Da are constants) and a first arc voltage calculating circuit,
An arc voltage setting signal calculation circuit receives the second current detection signal (Ifb), the feed speed setting signal (S1), and the tip distance setting signal (S2) as inputs, and the tip of the consumable electrode and the workpiece. S3b = S2-Lexb (where dLexb / dt = S1-Vmb Vmb = K1b × Ifb + K2b × Ifb ² × Lexb, where K1b and K2b are constants) ), The second current detection signal (Ifb) and the second arc length setting signal (S
3b) and the second arc voltage setting signal (Vr
b) Vrb = Ab + Bb × Ifb + (Cb + Db × Ifb)
5. A second arc voltage calculation circuit that calculates a value based on .times.S3b (where Ab, Bb, Cb, and Db are constants).
Or an arc loading device according to 5.