JP2015205332A - semi-automatic TIG welding torch and welding method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semi-automatic TIG welding torch excellent in welding workability in a narrow part capable of performing welding that exhibits a good appearance, and to provide a welding method using the same.SOLUTION: A semi-automatic TIG welding torch includes: a cylindrical torch body 1 in whose central part a TIG electrode 5 is arranged; a wire feeding guide 6 disposed close to the torch body 1 in parallel with the axis line of the torch body 1 for guiding a filler wire 7 to a welding part; a slide support 9 slidably fitted to the outer periphery of the torch body 1; and a rotatable support 8 rotatably provided to the slide support 9 for gripping the wire feeding guide 6 by a gripping part 8b that can expand and contract in a direction perpendicular to the axis line. The wire feeding guide 6 can rotate in a circumferential direction of the torch body 1, and move in the axis direction of the torch body 1 and in a direction perpendicular to the axis line.

Description

  The present invention relates to a semi-automatic TIG welding torch for gas shielded arc welding and a welding method using the welding torch.

Arc welding includes a consumable electrode type welding method that melts an electrode and a non-consumable electrode type welding method that does not melt an electrode. In the case of consumable electrode type welding, the welding efficiency is good, but spatter may be generated and it is necessary to remove it. TIG welding, which is non-consumable electrode type welding, has poor welding efficiency as compared with consumable electrode type welding, but can substantially suppress the occurrence of spatter.
Tig welding is sometimes applied to products that dislike foreign matters such as spatter and are subject to welding where multi-layer welding is required, although efficiency is low. In this case, in order to increase the welding efficiency as much as possible, a semi-automatic TIG torch equipped with a wire feed guide on the TIG torch has been developed instead of the conventional method of operating the filler rod with the hand opposite to the TIG torch. .
However, in a narrow part where there is not enough space to move the TIG torch freely, the TIG torch equipped with the wire feed guide is too large, and welding may not be possible or places that can be welded may be limited. .

  Therefore, as a semi-automatic TIG welding torch considering welding in a narrow part, for example, the base end of the wire feed support rod is detachably attached to the middle portion of the torch body by screwing, and at the tip of the support rod A welding torch having a configuration in which the wire feeding portion is detachably attached by screwing has been proposed. By separating the torch main body and the wire feeding part, welding work of the narrow part is made possible (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 02-118670 (page 4-5, Fig. 1)

  In the conventional semi-automatic TIG welding torch as shown in Patent Document 1, when welding a narrow part, the wire feeding part is separated from the torch body, and the torch body and the wire feeding part are operated by one hand each. We are going to weld while. Therefore, when skill level is required and the filler wire is energized and heated and fed, the feeding speed becomes faster, which makes the wire feeding operation more difficult, and the wire aiming position is shifted, When the wire touches the wire, spatter is generated and the appearance deteriorates. In addition, when performing upward welding, if the filler wire is in the wrong position and the arc is operated incorrectly, the wire touches the arc and the liquid drops fall under its own weight, which may exist as a large foreign object, which may adversely affect product performance. There was a problem that there was no.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a semi-automatic TIG welding torch and a welding method that have good welding workability in a narrow part and enable good welding. To do.

  The semi-automatic TIG welding torch according to the present invention is a semi-automatic TIG welding torch used in a semi-automatic TIG welding apparatus for welding while automatically feeding filler wires, and is a cylindrical torch main body having a TIG electrode mounted at the center. A wire feed guide that is arranged in the vicinity of the torch main body and parallel to the axis of the torch main body, guides the filler wire to the welding point, a slide support that is slidably fitted to the outer periphery of the torch main body, and a slide A rotation support that is provided on the support so as to be rotatable and grips the wire feed guide with a gripping portion that extends and contracts in a direction perpendicular to the axis, and the wire feed guide rotates in the circumferential direction of the torch body. In addition, it is configured to be movable in the direction of the axis of the torch body and the direction perpendicular to the axis.

  Further, a welding method according to the present invention is a welding method using the semi-automatic TIG welding torch, and the semi-automatic TIG welding torch has a function of controlling on / off of the arc current and feeding / stopping of the filler wire. The arc current and the wire feed amount are gradually decreased at the end of welding by the operation of the torch switch, and the wire feed is controlled to stop before the arc breaks.

  The welding method according to the present invention includes an arc torch switch for controlling on / off of the arc current and a wire feeding torch switch for controlling the feeding / stopping of the wire, and the wire feeding is performed at the end of welding. After the arc torch switch is stopped, the arc torch switch is turned off to decrease the arc current and the wire feed amount so that the wire feed is stopped before the arc breaks.

  According to the semi-automatic TIG welding torch of the present invention, the wire feeding guide is arranged in the vicinity of the torch body and parallel to the axis of the torch body, and is rotatable in the circumferential direction of the torch body. Since it is configured to be movable in the direction of the axis and in the direction perpendicular to the axis, stable welding is possible while confirming the welding location while firmly holding the torch body with both hands even when welding the welded part of the narrow part. Become. Accordingly, the main body of the torch does not greatly deviate from the weld line, the wire aiming position can be stably supplied to the molten pool, and a sound welded portion can be obtained.

  Further, according to the welding method of the present invention, a semi-automatic TIG welding torch is used to control one torch switch, or an arc torch switch for controlling on / off of the arc current, and wire feeding / stopping. Since the two torch switches of the wire feeding torch switch are controlled so that the arc current and the wire feeding amount are gradually decreased by the switch operation at the end of welding, and the wire feeding is stopped before the arc is cut. In addition, it is possible to improve the welding quality at the welding end portion.

It is a front view of the semiautomatic TIG welding torch by Embodiment 1 of this invention. It is sectional drawing seen from AA of FIG. It is a perspective view which shows the test piece which simulated the welding target object which has a narrow part. It is a schematic diagram in the case of welding a narrow part using the conventional TIG welding torch. It is a schematic diagram in the case of welding a narrow part using the semi-automatic TIG welding torch of FIG. It is a perspective view which shows the state in the middle of welding of FIG. It is a partial front view which shows the principal part of the semi-automatic TIG welding torch by Embodiment 2 of this invention. It is a perspective view which shows the state in the case of welding in the case of welding by a retraction method using the semiautomatic TIG welding torch of FIG. It is a time chart which showed transition with time passage of an arc current and wire feed speed explaining a welding method by Embodiment 3 of this invention. It is a front view of the semi-automatic TIG welding torch by Embodiment 4 of this invention.

Embodiment 1 FIG.
Hereinafter, a description will be given based on the drawings. FIG. 1 is a front view showing a semi-automatic TIG welding torch according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of FIG. 1 as seen from AA. In the figure, the direction of the axis of the welding torch will be described as the X axis, and the direction perpendicular to the axis will be described as the Y axis.

As shown in FIG. 1, a handle 2 having a variable angle is attached to a cylindrical torch body 1, and a torch switch 3 is provided on the handle 2. The tip of the torch body 1 has a nozzle 4 and a TIG electrode 5 is mounted at the center, and the tip of the TIG electrode 5 protrudes from the tip of the nozzle 4 by a predetermined dimension.
A wire feed guide 6 is disposed substantially parallel to the axis of the torch body 1. The distal end side of the wire feeding guide 6 is bent toward the central axis of the torch body 1. The filler wire 7 is inserted into the inside and becomes a path for automatically feeding the filler wire 7 to the welded portion. The wire feeding guide 6 is gripped by a rotation support tool 8, and the rotation support tool 8 is rotatably attached to a slide support tool 9. The slide support 9 is fitted on the outer periphery of the torch body 1 and is slidable in the X-axis direction.

Next, the mechanism of each support tool will be described in more detail with reference to FIG.
The rotation support 8 can be rotated about the X axis as a center axis while holding the wire feeding guide 6. Further, as shown in FIG. 2, it is configured to be movable in the Y-axis direction connecting the center of the wire feed guide 6 and the center of the torch body 1. That is, the rotation support 8 is divided into a rotation portion 8 a that is rotatably attached to the slide support 9 and a gripping portion 8 b that grips the wire feed guide 6 and is fastened by a bolt. And it can be moved in the Y-axis direction by loosening the bolt.
The slide support 9 can be slid in the X-axis direction with the wire feed guide 6 and the rotation support 8 fixed.
The movement mechanism in the Y-axis direction is an example, and is not limited to the figure.

Since the present invention is characterized in that the welding workability in the narrow portion is improved, the case where the narrow portion is welded using the semi-automatic TIG welding torch of FIG. 1 will be described.
FIG. 3 shows a test piece simulating a narrow part as an example. For example, a hole 11 a having a width of 150 mm, a height of 80 mm, and a depth of 80 mm is formed in the holed member 11. The case where the horizontal fillet multi-layer welding of the prismatic member 10 and the perforated member 11 is performed in the hole 11a portion will be described.

Normally, in TIG welding, forward welding is performed in which the direction of the TIG torch is the same as the welding progress direction in order to make it easier to confirm the front weld line. Further, the filler wire 7 for TIG welding is fed so as to enter the molten pool.
4 and 5 are cross-sectional views of the test piece of FIG. Among these, FIG. 4 shows a case where a conventional semi-automatic TIG welding torch such as Patent Document 1 described in the section of the prior art is used, and is shown for reference. In order to make the explanation easy to understand, portions corresponding to the present invention are denoted by the same reference numerals. FIG. 5 shows a case where welding is performed using the semi-automatic TIG welding torch of FIG. FIG. 6 is a perspective view showing a state in the middle of welding in FIG.

  As shown in FIG. 4, in the conventional semi-automatic TIG welding torch, the wire feed guide 6 interferes with the perforated member 11 near the end of welding. In order to avoid this, if the wire feeding guide 6 and the torch body 1 are separated and are operated with one hand at a time, the wire feeding guide 6 is brought closer to the torch body 1, and the wire feeding guide 6 6 and the hand holding the torch body 1 are close to each other, making it difficult to see the weld. Moreover, even if it tries to peep from the upper part of the hole 11a, it is difficult to see by the depth of the perforated member 11. Therefore, it is difficult to obtain a sound weld. Furthermore, in the multi-layer welding, as the number of passes increases, the wire feed guide 6 becomes closer to the torch body 1 and the welding becomes more difficult.

On the other hand, in the case of the present invention, as shown in FIG. 5, the wire feeding guide 6 is attached in parallel close to the torch body 1. In contrast, the filler wire 7 can be stably fed to the molten pool 13 formed by the arc 12 from the TIG electrode 5.
As shown in FIG. 6, when performing forward welding, by adjusting the rotation support 8 and the slide support 9 to adjust the position of the tip of the filler wire 7, the upper part of the molten pool 13, that is, from the welding line. In addition, the filler wire 7 can be properly fed to the upper portion, stable welding can be performed up to the welding end portion, and a sound welded portion can be obtained.

Next, the difference between the prior art and the present invention will be described in the case of performing upward welding. Consider the upward fillet multi-layer welding of the prismatic member 10 and the perforated member 11 of the test piece shown in FIG. Like the horizontal fillet multi-layer, the TIG torch takes an advance angle, and the filler wire 7 is inserted into the molten pool from the front in the welding direction. In this case, although illustration is omitted, in the prior art, if the torch body 1 and the wire feed guide 6 are held and operated one by one, the workability is poor due to upward welding, so the filler wire 7 is connected to the arc 12. May touch. At this time, a spherical molten metal is formed at the tip of the filler wire 7, and a situation occurs in which the droplet is separated from the tip due to the arc pressure or its own weight and drops.
On the other hand, in the semi-automatic TIG welding torch of the present invention, since the torch body 1 to which the wire feeding guide 6 is attached can be firmly fixed with both hands, only the position adjustment that allows the filler wire 7 to be fed to the molten pool 13 should be considered. The filler wire 7 does not touch the arc 12 and the droplets do not fall.

As described above, according to the semi-automatic TIG welding torch of the first embodiment, the cylindrical torch body with the TIG electrode attached to the center part, and the parallel to the axis of the torch body close to the torch body, A wire feed guide that guides the filler wire to the welding point, a slide support that is slidably fitted to the outer periphery of the torch body, and a grip that is provided on the slide support so as to be rotatable and expands and contracts in a direction perpendicular to the axis. The wire feed guide is rotatable in the circumferential direction of the torch body and movable in the direction of the axis of the torch body and in the direction perpendicular to the axis. In particular, when welding a welded portion of a narrow portion, stable welding is possible while confirming the welding location while firmly holding the torch body with both hands. Accordingly, the main body of the torch does not greatly deviate from the weld line, the wire aiming position can be stably supplied to the molten pool, and a sound weld can be obtained.
Also in the upward welding, the torch body can be easily operated without the wire touching the arc.

Embodiment 2. FIG.
FIG. 7 is a partial front view showing the tip of the semi-automatic TIG welding torch according to the second embodiment, and FIG. 8 shows a state in the middle of welding when welding is performed using the semi-automatic TIG welding torch of FIG. It is a perspective view shown. The semi-automatic TIG welding torch according to the present embodiment is basically the same as that shown in FIG. 1 described in the first embodiment, except that an energizing tip 14 for energizing the filler wire 7 with a heating current is provided. It is a point. The same parts as those in FIG.
As shown in FIG. 7, a current-carrying tip 14 is disposed inside the wire feed guide 6 on the front end side so that power is supplied from a heating power supply line (not shown).
By heating the filler wire 7, the amount of deposited metal per unit time can be increased and the welding speed can be increased, so that highly efficient welding is possible even with TIG welding.

  In the welding diagram of FIG. 8, the welding method is when the direction of the torch body 1 is tilted opposite to the welding beat to take a receding angle. If this welding is performed using a welding torch such as that disclosed in Patent Document 1 and the torch body 1 and the wire feed guide 6 are operated with one hand at a time, the wire feed speed is high, so In some cases, the filler wire 7 may hit the base material, and the reaction is transmitted through the wire feeding guide 6. For this reason, it is difficult to set the wire feeding place at a fixed position of the molten pool 13, and a situation occurs in which the wire is brought into contact with the arc 12 or goes out of the molten pool 13. When contacted with the arc 12, a short circuit occurs between the filler wire 7 and the arc 12, and sputtering occurs when the short circuit is released. Further, when the filler wire 7 goes out of the molten pool 13, the filler wire 7 comes into contact with the base material other than the welded portion and is short-circuited, and the filler wire 7 and the base material adhere to each other by resistance heating, so that the welding itself cannot be performed.

When the receding angle is taken, the size of the molten pool 13 is also smaller than when the advancing angle is taken, so that the target position tolerance is further narrowed. In addition, since the operability is also deteriorated in the welding of the narrow portion, the above-described problems occur more remarkably.
On the other hand, according to the semi-automatic TIG welding torch according to the present embodiment, the target position of the filler wire 7 can be finely adjusted even in a posture with a receding angle as shown in FIG. Since the wire aiming position can be suppressed, the wire feeding position can be fed to the molten pool 13 without touching the arc 12, and good welding can be obtained.

  Accordingly, the position of the filler wire 7 is finely adjusted using the automatic TIG welding torch shown in FIG. 7, and the filler wire 7 energized from the energizing tip 14 is melted by the arc 12 without touching the arc 12. By feeding to the pond 13, it is possible to perform welding with a high welding speed and high efficiency while suppressing the generation of spatter.

As described above, according to the semi-automatic TIG welding torch of the second embodiment, the wire feeding guide is provided with an energization tip for energizing the heating current to the filler wire. Since it is provided, the wire feeding amount can be increased, and the welding speed can be increased by increasing the amount of deposited metal per unit time, so that highly efficient welding is possible.
In addition, even when welding is performed with a receding angle and a high welding speed, it is easy to hold the torch body with both hands and feed the wire feeding position to the molten pool without touching the arc. Welding can be obtained.

  In addition, according to the welding method using the semi-automatic TIG welding torch of the second embodiment, the filler wire energized from the energizing tip is fed to the molten pool formed by the arc without touching the arc. High efficiency and low spatter welding is possible.

Embodiment 3 FIG.
The third embodiment relates to a welding method that effectively performs TIG welding using a semi-automatic TIG welding torch as in the first or second embodiment.
The semi-automatic TIG welding torch is a case where one torch switch 3 is provided as shown in FIG. The torch switch 3 has a function of controlling on / off of the arc current and feeding / stopping of the filler wire.
FIG. 9 is a diagram for explaining the welding method according to the third embodiment, and shows the time-dependent transition of the operation of the torch switch 3, the arc current, and the feeding speed of the filler wire 7 (hereinafter abbreviated as wire speed). It is a chart.

The operation will be described with reference to FIG.
First, when a torch switch 3 provided on the handle 2 of the torch body 1 is pressed once, a start current smaller than this current flows to the welded portion via the TIG electrode 5, thereby generating an arc. As soon as the start current starts to flow, the filler wire 7 starts feeding at a low speed. While the torch switch 3 is being pressed, a start current flows and the filler wire 7 is at a low speed, but the arc current shifts to this current immediately after being released. At the same time, the wire speed of the filler wire 7 is increased.

  Subsequently, when the torch switch 3 is pressed once again at the welding end portion, the current gradually decreases from this current, and the arc is cut after a certain time. The wire speed also starts to decrease immediately after the torch switch 3 is pressed, and the feeding stops after a certain time. Here, the wire speed is controlled by a control unit (not shown) so that the wire feeding is stopped before the arc is cut. This is to prevent the bead shape from deteriorating when the filler wire 7 is fed even after the arc is cut, because the wire is deposited at the location where the molten pool disappears. In addition, after the wire feeding is stopped, since the molten pool is leveled by the arc, a beautiful bead shape without unevenness can be obtained by taking an arc current and time for holding the arc to some extent.

Also, at the start of welding, if the filler wire is fed at a high speed before shifting to the main current, the filler wire is fed to a small molten pool. However, since the wire speed was lowered at the start current, there is no worry about that.
Further, since the single torch switch 3 is provided with functions for arcing and wire feeding, in particular, as in the case of the embodiment 2 in which the wire feeding guide 6 is provided with the energizing tip 14, the wire feeding is performed. Even when the feeding speed is fast, the switch operation is easy.

  As described above, according to the welding method according to the third embodiment, the semi-automatic TIG welding torch using the semi-automatic TIG welding torch according to the first or second embodiment is used. One torch switch with the function of controlling on / off of the filler wire and feeding / stopping of the filler wire, and by operating the torch switch, the arc current and the wire feed amount of the filler wire are gradually reduced at the end of welding. Since the wire feed is controlled to stop before the wire breaks, in addition to the effects of the first or second embodiment, it is possible to improve the welding quality of the welding end portion by a simple switch operation.

Embodiment 4 FIG.
FIG. 10 is a front view of a semi-automatic TIG welding torch according to the fourth embodiment. Basically the same as FIG. 1 of the first embodiment, but the difference is that two torch switches are provided. Since other than that is the same as FIG. 1, an equivalent part is shown with the same code | symbol and description is abbreviate | omitted.
As shown in FIG. 9, an arc torch switch 3 a and a wire feeding torch switch 3 b are individually provided on the handle 2.

As in the case of the third embodiment, the operability increases if the arc and wire feeding torch switches are integrated into one, but in reality, the crater treatment method and processing time at the welding end part are actually determined by the welding operator. Since they are different, it becomes necessary to individually set the arc current and the wire feed control.
In the welding method of the present embodiment, an arc is first generated by the arc torch switch 3a, and after the transition to the main current, wire feeding is started by the wire feeding torch switch 3b. At the welding end portion, the wire feeding torch switch 3b is pushed again to stop the wire feeding. Thereafter, the arc torch switch 3a is pressed to cut the arc and complete the welding. Thereby, it becomes possible to obtain substantially the same weld bead regardless of the welding ability of the welding operator.

  As described above, according to the welding method according to the fourth embodiment, the semi-automatic TIG welding torch includes an arc torch switch that controls on / off of the arc current and a wire feed that controls the feeding / stopping of the filler wire. It has a feeding torch switch, and after the wire feeding torch switch is stopped at the end of welding, the arc torch switch is turned off, the arc current and the wire feeding amount of the filler wire are reduced, and the arc is cut. Since the wire feeding is controlled to be stopped before, the welding quality of the welding end portion can be improved without being greatly affected by the welding ability of the welding operator.

  In the present invention, it is possible to freely combine the respective embodiments within the scope of the invention, and to appropriately change or omit the respective embodiments.

  1 Torch body, 2 handle, 3 torch switch, 3a arc torch switch, 3b torch switch for wire feeding, 4 nozzle, 5 TIG electrode, 6 wire feeding guide, 7 filler wire, 8 rotating support, 8a Rotating part, 8b gripping part, 9 slide support, 10 prism member, 11 perforated member, 11a hole, 12 arc, 13 molten pool, 14 energizing tip.

Claims (5)

A semi-automatic TIG welding torch used in a semi-automatic TIG welding apparatus for welding while automatically feeding filler wire,
A cylindrical torch body with a TIG electrode attached to the center,
A wire feed guide that is disposed in parallel to the axis of the torch body in the vicinity of the torch body and guides the filler wire to a welding point;
A slide support slidably fitted to the outer periphery of the torch body;
A rotation support provided on the slide support so as to be rotatable, and holding the wire feeding guide by a holding portion extending and contracting in a direction perpendicular to the axis.
The wire feeding guide is configured to be rotatable in the circumferential direction of the torch body and to be movable in the direction of the axis of the torch body and in the direction perpendicular to the axis. Welding torch. The semi-automatic TIG welding torch according to claim 1,
The semi-automatic TIG welding torch, wherein the wire feeding guide includes an energization tip for energizing a heating current to the filler wire.   A welding method for performing semi-automatic TIG welding using the semi-automatic TIG welding torch according to claim 2, wherein the filler wire energized from the energizing tip is applied to the molten pool formed by the arc without touching the arc. A welding method characterized by being fed. A welding method for performing semi-automatic TIG welding using the semi-automatic TIG welding torch according to claim 1 or 2,
The semi-automatic TIG welding torch has one torch switch having a function of controlling on / off of the arc current and feeding / stopping of the filler wire, and the arc current and the above-mentioned at the end of welding by operating the torch switch A welding method characterized in that the wire feed amount of the filler wire is gradually decreased so that the wire feed is stopped before the arc is cut. A welding method for performing semi-automatic TIG welding using the semi-automatic TIG welding torch according to claim 1 or 2,
The semi-automatic TIG welding torch has an arc torch switch for controlling on / off of the arc current and a wire feeding torch switch for controlling feeding / stopping of the filler wire, and the wire feeding at the end of welding. After the arc torch switch is stopped, the arc torch switch is turned off to decrease the arc current and the wire feed amount of the filler wire, and control to stop the wire feed before the arc breaks. The welding method characterized by performing.

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