JP2001105140A - Hot wire welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the possibility of the instability of an arc due to a magnetic blowing caused by a wire electric current. SOLUTION: The hot wire welding equipment (TIG welding torch) is provided with a hot wire TIG welding power supply where the energizing term of a heating electric current for one or more added wires 10 is controlled by being synchronized with an oscillation phase of a TIG arc which oscillates in a wide range where the amplitude is 10 mm or greater and the frequency is 10 Hz or greater. In this case, when two or more wires 10 are used, an energizing time is controlled so that each of the wires 10 is not energized simultaneously and a power supply transformer is so constructed as to supply one or more independent wire heating currents. The energizing term of each heating electric current supplied to plural added wires 10 is controlled to stabilize the magnetic blowing condition of the arc and multiple outputs are available from a single power supply by preventing the simultaneous energizing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot wire welding apparatus (TIG welding torch), and more particularly to a power supply for hot wire TIG welding suitable for broadly overlaying different materials on a base material.

[0002]

2. Description of the Related Art In the case of overlay welding using a TIG arc, conventionally, a TIG arc torch and a wire-added torch are integrally combined, or a TIG arc torch with a fixed wire torch is weaved at a frequency of 10 Hz or less. Moving).

[0003] In any case, TI with a width exceeding 10 mm
Conventionally, when moving a G arc, it is usual to mount the TIG torch on a slide base or a robot and move the entire TIG torch with a robot arm. Was a low weaving frequency of 10 Hz or less.

On the other hand, Japanese Patent Application No. Hei 11
-055563 device, ie, an arc current of 300
A TIG arc of A or more is generated, and an amplitude of 10 mm
An apparatus for overlay welding using a TIG arc while oscillating the tip of a tungsten electrode at a frequency of 30 mm and a frequency of 30 Hz has been put into practical use. In that device, one or two,
A plurality of hot wires, such as three, are fed so that overlay welding can be performed with high efficiency.

FIG. 6 is an explanatory view schematically showing the welding head 1 of the apparatus disclosed in Japanese Patent Application No. Hei 11-055623. FIG.
Is the T when the welding head portion 1 in FIG. 6 is viewed from the melting direction.
It is explanatory drawing which showed schematically the connection state of the IG arc torch part 2, the wire torch part 3, and the welding power supply, etc.

[0006] Inside the welding head 1 shown in FIG.
A mechanism for swinging the IG torch 2 in a pendulum shape is incorporated. That is, the torch portion 2 having the tungsten electrode 4 attached to the tip is mechanically directly connected to the electromagnetic actuator 5 via the insulating member 6, and the TIG torch portion 2 is restrained from both sides by springs (not shown). Actuator 5
And a self-oscillation at a frequency of 10 Hz or more by the action of the driving force and the spring. are doing. The TIG torch 2 is connected to two cooling water hoses (not shown), and a copper chip 7 holding the tungsten electrode 4 at the tip of the torch 2.
Is water cooled.

The electromagnetic actuator 5 is fixed to a housing 9 of the welding head 1 by a support 8. On the other hand, the addition wire 10 is supplied from a wire feeder (not shown) to the contact tube 1 via a conduit (not shown).
1. It is fed to the molten pool 14 on the base material 13 through the ceramic guide 12.

[0008] As shown in FIG.
a, 3b, and 3c, each of which is separately connected to the + terminal side of three wire heating power supplies 15a, 15b, and 15c. And each wire power supply 15a, 15b, 15c
Is connected to the base material 13. Also TIG
The torch part 2 is connected to the negative terminal side of the arc power supply 16, and the + terminal of the arc power supply 16 is connected to the base material 13.

Thus, an arc 17 (FIG. 6) is formed between the tungsten electrode 4 and the base material 13. The tip of the tungsten electrode 4 swings sinusoidally in a pendulum shape as shown by an arrow in FIG. 7 with the axis 18 of the electromagnetic actuator 5 as a fulcrum. The distance from the shaft core 18 to the tip of the tungsten electrode 4 is about 200 mm. When the TIG torch 2 swings ± 7.1 degrees, the total swing width of the tip is 50 mm.

A gas hose (not shown) is connected to the housing 9 so that a shield gas flows out from a shield nozzle 19 attached to the TIG torch 2 and the wire torch 3. In this way, the wire 10 is supplied to the arc 17 generating portion, and the overlay bead 20 is formed on the base material 13.

[0011]

In the above prior art, when a pulse current of, for example, 100 Hz is used for heating the wire,
Since the energizing frequency is different from the swing frequency of the arc, there has been a problem that the magnetic blowing phenomenon of the arc is severely generated or no longer occurs, and the state of the arc cannot be stabilized. Also, since the number of wire heating power supplies for the number of wires was used, the cost of power supply equipment became expensive,
There is also a problem that a large installation space is required.

An object of the present invention is to further reduce the problem of arc instability due to magnetic blowing by a wire current in a hot wire welding apparatus. Another object of the present invention is to provide a power supply for heating a wire that is more economical and has a smaller installation space in a hot wire welding apparatus.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned first problem, the present invention provides a control apparatus for a wire heating power supply for controlling a current supply period of a wire heating current so as to synchronize with a swing phase of a TIG arc. Was provided. In order to solve the second problem, the power supply timing is controlled so that the wires are not supplied simultaneously, and one power supply transformer outputs one or more independent wire heating currents.

That is, the present invention has the following configuration. It has a wide swinging TIG arc electrode connected to an arc power supply (minus output terminal) and one or more additional wires connected to a wire power supply (plus output terminal). In a hot wire welding apparatus for welding a base material connected to a wire power source (a minus output terminal thereof), a wire power source controls a current supply period of a heating current of an additional wire in synchronization with a swing phase of a swinging TIG arc electrode. A hot wire welding apparatus (TIG welding torch) characterized by comprising a control device to be used.

At this time, the control device of the wire power supply is configured to control the energization timing so that each of the two or more additional wires is not energized simultaneously. For example,
When the arc electrode oscillates and the arc is at the R (right) side end, a current flows through the wire torch on the opposite side, and L
When the current is supplied to the wire torch on the opposite side when it is at the left end, the distance between the wire current and the arc is long, and no magnetic blowing occurs.

When an electric current is applied to the wire torch at the center when the arc passes through the center of the swing, the arc passes near the conducting wire at this time.
This produces magnetic blowing. However, since the magnetic blowing in the same state is always generated, the molten state of the base material is stable compared to the case where the magnetic blowing is not generated or stopped.

Further, the control device of the wire power supply switches so that the current supply to the plurality of wires does not overlap. Therefore, even when the current is supplied to the plurality of wires, the circuit on the primary side of the power supply and the transformer are one set. The power supply can be manufactured at a lower cost and can be made smaller as compared with the case where three individual power supplies 15a to 15c are provided as shown in FIG.

Thus, the TIG arc electrode has an amplitude of 10 m.
The molten state of the base material 13 is stable even in a configuration in which the base material 13 swings widely at m or more and at a frequency of 10 Hz or more.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The swing mechanism of the TIG torch 2 of the hot wire TIG welding device according to the present embodiment is as follows.
Since it is the same as that shown in FIG. 6, its illustration and description are omitted.

FIG. 1 shows a hot wire T according to this embodiment.
FIG. 1 is a configuration diagram of an IG welding apparatus, and shows an electrical connection relationship between a wide swing TIG welding head 1, an arc power supply 16, and a wire power supply 21. The welding head 1 has three wire torches 3a, 3b, 3c, which are connected to the +1, +2, +3 output terminals of the wire power source 21, respectively.
The − (minus) output of the wire power supply is connected to the base material 13. The-(minus) output of the arc power supply 16 is connected to the welding torch 2, the + (plus) output is connected to the base material 13, and the tungsten electrode 4 has the R direction and the L direction as shown by arrows in FIG. The base material surface is melted by an arc (not shown) generated between the base material 13 and the base material 13 while swinging widely in a pendulum shape.

FIG. 2 shows a main circuit configuration of the wire power supply 21 of FIG. 3 phase 2 from u, v, w input terminals
Input 00V, convert to DC by rectifier circuit RC, 20KHz by H bridge circuit HB consisting of large capacity transistor
And connected to the primary side of the transformer T. The secondary side of the transformer T is rectified by the diodes D1 and D2.
Each output on + (plus) side via R1, TR2, TR3 +
1, +2, +3, and the-(minus) side is connected to one-(minus) output terminal.

The controller CTLR has input signals s, n, i
1, i2, i3 and i come in and output signals t, t
1, t2 and t3 are output. The input signal s is an output signal of a torch position detection sensor that outputs high H when the TIG torch 4 stays on the R side from the center of swing when the TIG torch 4 swings like a pendulum, and outputs low L when it stays on the L side. . The signals of the number of terminals actually output, i1, i2, and i3, are current setting signals for setting the peak values of the output currents from the output terminals +1, +2, and +3 of the wire power supply, respectively. i is a current signal from the Hall sensor H that detects a secondary current.
t is a switching signal to the power transistor constituting the H bridge, and t1, t2, and t3 are signals for turning on and off the output side, respectively.

FIG. 3 is a diagram for explaining the relationship between the wire heating currents I1, I2, I3 output from the wire power supply 21 of FIG. 2 and the tip position of the tungsten electrode 4 when three wires are added.

Since the wire power supply 21 has the configuration shown in FIG. 2, it operates as follows to form the output shown in FIG.
The controller CTLR knows the number of terminals to be output from the input signal n, obtains the swing phase from the signal s, and outputs the output currents I1, I2,
The output period of I3 is set. As shown in the I1 current waveform of FIG. 3, the period of the phase of the swing from 0 to 2π / 3 is defined as the I1 output period, and during that period, a switching signal based on the current setting signal i1 of I1 is formed to generate H1. To the bridge HB, and at the same time, the controller CTLR controls the control signals t1, t2, t
3 to output the switching transistor TR1 on the secondary side.
Is turned on, and TR2 and TR3 are turned off.

A feedback control is performed by returning a value detected by the Hall sensor H to the controller to determine whether the current I1 has a value corresponding to the setting signal i1. Similarly, during the period of the swing from 2π / 3 to 4π / 3, I2 is output,
I3 is output during the period of the swing from 4π / 3 to 0.

FIG. 4 shows a case where two wires are fed using the torch 10a and the torch 10c. FIG. 5 shows a case where one wire is fed using the torch 10b. As shown in FIGS. 3 to 5, since the wire is energized in synchronization with the swing phase, the state in which the arc is magnetically blown by the wire current is always constant and stable. In the case of FIG.
Swings to supply an I1 current to the wire torch 10a on the opposite side when the arc is at the R end, and to supply an I3 current to the wire torch 10c on the opposite side when the arc is at the L end. Therefore, the distance between the wire current and the arc is long, and no magnetic blowing occurs.

When the arc passes through the center of the swing, an I2 current is supplied to the wire torch 10b at the center. At this time, the arc passes near the current-carrying wire. Occurs. However, since the magnetic blowing in the same state is always generated, the molten state of the base material 13 is stable compared to the case where the magnetic blowing is not generated or stopped.

In the case where the number of wires in FIG. 4 is two, the wire torches 10a and 10c are used to control so that current is always supplied to the wire on the side opposite to the direction in which the arc stays. In the case of the book, the wire is controlled by using the wire torch 10b so that the wire is energized when the arc is at both ends on the L side and the R side. Thus, magnetic blowing of the arc by the wire current is prevented.

The wire power supply 21 has a circuit principle as shown in FIG. 2, and the power supply to the wires 10a to 10c is switched so as not to overlap.
Even when power is supplied to the power supplies 0a to 10c, only one set of the circuit on the primary side of the power supply and the transformer T need be provided, so that compared with the case of providing three individual power supplies 15a to 15c as shown in FIG. The power supply can be manufactured inexpensively and is small.

In the above embodiment, the wire 10
The case where the number of a to c is three at the maximum has been described.
Even if the number of wires, such as five or five wires, further increases, the wire power supply 21 can be configured in the same way.

[0031]

According to the present invention, the energization period of each of a large number of wires can be controlled in association with the staying position of a wide swinging arc, so that the occurrence of magnetic blowing of the arc can be reduced. Even when the magnetic blowing of the arc occurs, the arc is generated in a constant state, so that the generation of the arc and the molten state of the base material are stabilized.

Further, according to the present invention, only one set of the primary circuit of the inverter power supply needs to be provided, and the secondary side has multiple outputs, but mutual control is performed by the control device inside the power supply device. Therefore, the overall configuration can be inexpensively configured as compared with an independent multi-unit power supply, and can be manufactured compactly as a whole, so that the installation space is more reduced.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a welding device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a circuit principle of a wire power supply according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a wire energizing period according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram of a wire energizing period according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram of a wire energizing period according to the embodiment of the present invention.

FIG. 6 is an explanatory view of a welding head portion of a welding device proposed by the present inventors previously.

FIG. 7 is an explanatory diagram of a configuration including a power source of a welding device proposed by the present inventors previously.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Welding head 2 TIG torch 3 Wire torch 4 Tungsten electrode 5 Electromagnetic actuator 6 Insulation material 7 Copper chip 8 Support stand 9 Housing 10 Wire 11 Contact tube 12 Ceramic guide 13 Base material 14 Melt pool 15 Wire power supply 16 Arc power supply 17 Arc 18 axis Core shaft 19 Shield nozzle 20 Overlay bead 21 Wire power supply

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshiharu Nagashima 5-3 Takaracho, Kure-shi, Hiroshima Fab term in Bab Hitachi Industrial Co., Ltd. (reference) 4E001 AA03 BB07 DB01 DC02 DF04 EA01

Claims (4)

[Claims] 1. A wide swinging T connected to an arc power supply
In a hot wire welding apparatus having an IG arc electrode and one or more additive wires connected to a wire power source and welding a base material connected to the arc power source and the wire power source, the wire power source swings the oscillating TIG arc electrode. A hot wire welding apparatus, comprising: a control device that controls a current supply period of a heating current of an additive wire in synchronization with a phase. 2. The hot wire welding apparatus according to claim 1, wherein the control device for the wire power supply is configured to control the energization timing so that each of the two or more additional wires is not energized simultaneously. apparatus. 3. The hot wire welding apparatus according to claim 2, wherein the wire power control device is configured to output two or more independent wire heating currents from one power transformer. 4. The hot wire welding apparatus according to claim 1, wherein the TIG arc electrode has a configuration in which the TIG arc electrode swings widely at an amplitude of 10 mm or more and a frequency of 10 Hz or more.