JPH11277242A - Welding torch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the fluctuations in the position of a wire front end and to enable the inexpensive and easy exchange of consumable members by providing a welding tip of which one end side or the part near this side comes into contact with a torch front end member and functions as a turning fulcrum of the welding tip and the other end side energizes a wire, by which sure contact welding is executed. SOLUTION: The wire 3f is introduced from a torch body part to a torch front end member 16a by passing the wire guide hole 20a of a screw 17a and is passed through the guide hole 2f of a ceramic sleeve 21a. The wire arrives at a weld zone while coming into light contact with the power feeding part 25a of the welding tip 18a pressed by a leaf spring 19a at the point where the wire emerges from the ceramic sleeve 21a. Arc current is supplied to the torch front end member 16a coupled by a screw 17a from the torch body and enters the welding tip 18a by passing the contact welding part between a U-shaped groove 22a of the torch front end member 16a and the welding tip 18a fitted at one end therein. The arc current flows to an arc forming part through the wire 3f in contact with the power feeding part 25a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic arc welding apparatus, and more particularly to an arc welding torch suitable for feeding a wire to a welding portion while supplying a stable current to the welding wire.

[0002]

2. Description of the Related Art In most cases, the cross section of a wire used as an electrode in conventional consumable electrode arc (hereinafter, abbreviated as GMA) welding is circular, and a welding tip of a welding tip for conducting electricity to the wire and guiding it to a welded portion. The guide holes were mostly circular. FIG. 24 is a central cross-sectional view showing a typical current-carrying tip 1a attached to a conventional GMA welding torch and its guide hole 2a.

Usually, the length of the tip 1a is about 45 mm, and the diameter of the guide hole 2a is
For example, a wire having a diameter of 1.2 mm has a hole having a diameter of 1.3 to 1.4 mm. The material of the chip 1a is usually chromium copper or the like from the viewpoint of wear resistance and conductivity. The wire 3a is fed in a slightly bent state so as to conduct electricity at the tip outlet 4a.

[0004] In the case of mild steel or the like, the wire is copper-plated to prevent rust, improve lubrication of feed, and improve contact conductivity. However, the inner surface of the conduit (not shown) that guides the wire from the wire feeding device to the welding torch, the inner surface of the welding torch or the contact between the tip and the wire surface, or when passing through the feeding roller of the wire feeding device, the copper is damaged. The plating may come off, or the wire may be shaved to generate chips. Such chips, plating debris, and dust and rust attached to the wire are collectively referred to as foreign matter. The foreign matter is conveyed by the side of the wire during wire feeding and passes through the gap between the guide hole and the wire. Some are discharged outside the chip.

However, when the gap between the guide hole and the surface of the wire is not so large, foreign matter is accumulated before entering the guide hole and in the chip, and the wire is caught by the foreign matter and the feeding resistance is increased by the wire. It prevents passage of the wire or pinching between the wire and the chip, thereby preventing contact current to the wire. This uneven supply and the instability of the contact current directly cause an arc break in the case of GMA welding, causing problems such as frequent spatters and arc instability. Further, at the start of energization, sparks may be generated between the wire and the chip, and the chip and the wire may be fused to be unusable.

FIG. 25 shows a cross section 4b of an outlet of a current-carrying chip 1b for GMA described in Japanese Patent Application Laid-Open No. 6-304761 by the same applicant as the present application. Since the guide hole 2b is a regular triangle, the wire 3b contacts the inner surface of the current-carrying chip 1b at two points 5b-1, 5b-2. Even if the inscribed circle of the triangle is a value very close to the diameter of the wire, foreign matter is discharged at the corner of the triangle having a sufficient space, so that chip clogging by the foreign matter does not occur. Although the current-carrying properties were considerably improved by these, the smaller the gap between the triangular inscribed circle and the wire 3b, the larger the wire diameter due to the manufacturing tolerance of the wire diameter, or the feeding roll of the wire feeding device. If the cross section of the wire 3b is slightly mechanically deformed due to, for example, a problem arises that the wire 3b is immediately caught by the guide hole 2b and clogged.

Therefore, in practical use, the diameter of the triangular inscribed circle needs to be about 0.04 mm larger than the nominal wire diameter in order to secure a gap with the wire 3b. That is, even in the current-carrying tip of the present invention, there is "play" between the wire 3b and the current-carrying tip 1b, and there is essentially no difference in that the wire 3b needs to be bent for current supply.

Normally, the current-carrying tip as shown in FIG. 24 is attached to a welding torch (not shown), and the torch is used for semi-automatic welding or mounted on a welding robot.
When mounted on a welding robot, usually, the wire 3a is taken out of the tip 1a assuming a state at the time of welding prior to welding, and the path is taught by following the welding groove at the tip of the wire.
Thereafter, playback is performed to execute welding. However, at the time of playback, the gap between the guide hole 2a and the wire 3a or the direction of bending of the wire 3a as shown in FIG. 24 changes from the case of the initial setting, so that the tip of the wire 3a may deviate from the target position. In some cases, the beads meander during welding to cause poor welding.

Therefore, during use of the tip, the tip is selectively formed due to mechanical abrasion caused by the wire being pressurized at the tip due to bending of the wire, and sparking caused by energizing while feeding the wire. However, since the wear of about 5 mm from the tip of the tip significantly affects the displacement of the tip of the wire due to the bending tendency of the wire,
Even if there is no problem with the contact current, the chip is determined to have reached the end of its life and has been replaced.

[0010] Therefore, it is desirable that the wire exits from the guide hole with as small a gap as possible, and a wire with a large radius of curvature is used. However, when a straight wire is passed through a straight guide hole, there arises a problem that a contact energizing position in the guide hole becomes unstable.

In order to adopt a straight wire, there is a known example in which a technique of pressing a wire from the side against a surface of a current-carrying guide hole by a spring (Japanese Patent Laid-Open No. 64-18582) is used. FIG. 26 is a view for explaining a known example of the wire 3c.
Is pressed against the inner surface of the guide hole 2c of the chip 1c. Metallic carbon, leaf spring 6
When a conductive material is used, the wire 3 can be
Although it is described that power is supplied to c, in practice, it is presumed that power is supplied mainly by contact on the surface of the guide hole 2c. This structure has a problem that when the wear of the chip progresses or when a foreign substance is clogged, the entire complicated and expensive chip 1c must be replaced.

On the other hand, in the case of hot wire TIG welding, the distance from the wire current-carrying point in the current-carrying tip to the base metal is usually kept at a constant value in the range of about 30 mm to 70 mm for wire heating. In order to keep the state constant, the distance between the tungsten electrode and the tip of the hot wire needs to be kept constant so that the influence of arc heat is kept constant. Therefore, a non-conductive ceramic guide is often arranged at the tip of the current-carrying tip so that the occurrence of wire tip displacement due to the bending tendency of the wire is reduced as much as possible.

In this case, if the ceramic guide and the wire guide hole of the current-carrying chip are arranged in a straight line, the wire is restrained by the ceramic guide and it is difficult to always contact the current-carrying chip. And the guide hole axis of the current-carrying tip are slightly inclined, or the ceramic guide 8d is attached to the tip of the current-carrying chip 1d which is bent as shown in FIG. In this case, the current is reliably supplied, but the wire feeding resistance is remarkably increased to cause uneven wire feeding.

FIG. 28 is a view showing the structure of the tip of the torch described in Japanese Patent Application Laid-Open No. Hei 7-236974 filed by the same applicant as the present application. A ceramic guide member 10e provided with a V groove for guiding the wire 3e is attached with a screw 11e-1. Numeral 12 denotes an energizing tip for energizing the wire, and the wire 3e is sandwiched between the ceramic guide member 10e using a screw 11e-2 and a spring 6e-2. A flexible energizing cable 13 is screwed to the energizing tip 12 and the torch main body member 9 with screws 11e-3 and 11e-4, and these are electrically connected.

Reference numeral 14 denotes a ceramic holding plate.
Screws 11e-5, 11e-6 and springs 6e-5, 6e-6
Between the ceramic guide member 10e and the wire 3
e. With the use of such a pressure contact structure and the use of the ceramic guide 10e, even if the ceramic guide is attached to the tip, the wire feed resistance is kept low.
Stable electrical conductivity can be maintained.

However, this torch has a problem such as a complicated overall structure. Above all, a thick flexible current-carrying cable 13 is required in order to allow a high current to flow through the wire. The rigidity tends to be higher than the strength of the holding spring 11e-2 for maintaining an appropriate pressing force, and after all, a stronger spring is used to keep the force for holding the wire stable. And the chip life becomes relatively short.

[0017]

SUMMARY OF THE INVENTION It is a first object of the present invention to provide a means for solving the above-mentioned problems in the consumable electrode arc with a simple torch structure. That is, even if a wire having a bending habit is used, even if a wire having a small bending habit and a large radius of curvature is used, contact energization is reliably performed and no arc break occurs, and an arc is generated. Less variation in wire tip position,
Another object of the present invention is to provide a torch for consumable electrode arc welding in which a consumable member is inexpensive and easily replaceable.

A second object of the present invention is to provide a hot wire TI
It is an object of the present invention to provide a means for solving the above-mentioned problems when a ceramic guide is used in G welding with a small and simple torch structure. That is, an object of the present invention is to provide a torch for hot wire welding in which contact energization is reliably performed, a feeding resistance is small, and consumable members are inexpensive and easily replaceable.

[0019]

In order to solve the above problems, the present invention mainly employs the following configuration.

A welding torch comprising: a torch tip member through which a wire is inserted; an energizing tip that contacts the wire to energize the wire; and an elastic member that presses the energizing tip toward the wire. The current-carrying tip is pressed by the elastic member, one end side or one end side vicinity thereof abuts on the torch tip member and functions as a rotation fulcrum of the current-carrying tip, and the other end side is substantially connected to the wire in the wire length direction. A welding torch that comes into contact with the wire in a vertical direction and that energizes the wire from the torch tip member via the energizing tip.

In the welding torch, a ceramic guide for guiding the wire is provided inside the tip member of the torch, and immediately after the wire passes through the ceramic guide, the other end of the current-carrying tip is connected to the wire. Torch for contact with

In the welding torch, a ceramic guide for guiding the wire is attached to an end of the torch tip member, and one end of the current-carrying tip is inserted immediately before the wire is inserted from the torch tip member into the ceramic guide. A welding torch whose side abuts on the torch tip member.

In the welding torch, a ceramic guide for guiding the wire is attached to an end of the torch tip member, and immediately before the wire enters the ceramic guide, the other end of the current-carrying tip is connected to the wire. Contact torch for welding.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment of an arc welding torch according to the present invention will be described with reference to the drawings. FIG. 1 is a plan view around a torch tip 15 of an arc welding torch according to an embodiment of the present invention.
Functionally, it is equivalent to the conductive chip 1a of FIG. FIG. 2 is a sectional view taken along the center line of FIG. 1, and FIG. 3 is a sectional view taken along line AA of FIG. 1, showing a state of a contact conducting portion 24a between the torch tip member 16a and the conducting tip 18a. FIG. 4 is a sectional view taken along the line BB of FIG.
This indicates that there is a gap a between "a" and "a". FIG. 5 is a cross-sectional view taken along the line CC of FIG. 1, and shows a state of contact with the wire 3f when the current-carrying tip 18a is new. FIG. 6 shows a state of contact with the wire 3f when the wear progresses by using the current-carrying tip 18a.

In FIG. 1, reference numeral 16a denotes a torch tip member made of chrome copper for a wire having a diameter of 1.2 mm, and its approximate dimensions are 14 mm long × 12 mm wide × 40 mm long. The torch tip member 16a is connected to a torch main body (not shown) via a screw 17a, serves as a conductor for supplying an arc current from the torch main body, and has a torch tip connected to a water-cooled torch main body. In addition to the member 16a itself, it also serves as a heat conductor for cooling the current-carrying tip 18a and the leaf spring 19a so as not to be overheated by heat from an arc or the like.

The screw 17a has a wire guide hole 20a which is considerably thicker than the wire diameter at the center axis thereof. A ceramic sleeve 21a having an outer diameter of 5 mm and having an equilateral triangular guide hole 2f made of silicon nitride excellent in heat resistance and wear resistance and having an inscribed circle having a diameter of 1.24 mm is provided on the tip side of the torch tip member 16a. Embedded as a member.

FIGS. 7 to 9 show the torch tip member 16a of FIG.
7 is a plan view, and FIG. 8 is a side view thereof. In FIG. 7, "M" represents the diameter of the female screw into which the screw 17a of FIG. 1 is inserted, and the prepared hole of the female screw is slightly larger than the "d2" hole into which the ceramic sleeve 21a is inserted.
The ceramic sleeve 21a can pass through. In order to prevent the ceramic sleeve 21a from being pulled out by the wire 3f, the torch tip member 16a is provided with a tapered tapered hole having a tip end side with a diameter "d1" smaller than "d2". Thus, the torch tip member 16
a surrounds the ceramic sleeve 21a, and the torch tip member 16a also serves to position the ceramic sleeve 21a and protect the ceramic sleeve 21a from being broken by an external force.

As shown in FIGS. 7 and 8, a U-shaped groove 22a is provided at the center of the torch tip member 16a, and one end of the current-carrying tip 18a is inserted into the groove and hooked. I have. 9, 10, and 11
9 is a view for explaining the shape of the conducting chip 18a in FIG. 1, FIG. 9 is a plan view, FIG. 10 is a side view thereof, and FIG.
FIG. The energizing tip 18a has a general external dimension 1
It is made of 2mm x 7mm x 26mm chromium copper.

As shown in FIG. 2, one end of the leaf spring 19a is brought into close contact with the torch tip member 16a by holding screws 23a-1 and 23a-2, and is used for fixing the leaf spring 19a and cooling the leaf spring 19a. Has also helped. By pressing down the energizing tip 18a with the other end of the leaf spring 19a, the energizing tip 18a is
It is configured to be pressed against the V-shaped groove 22a and the wire 3f protruding from the triangular guide hole 2f of the ceramic sleeve 21a.

The arc welding torch according to the embodiment of the present invention is composed of the elements described above, and is assembled as shown in FIGS. 1 and 2 and operates as follows.

The wire 3f is introduced from the torch main body (not shown) into the torch tip member 16a through the wire guide hole 20a of the screw 17a, passes through the guide hole 2f of the ceramic sleeve 21a, and is moved by the leaf spring 19a. The pressed power supply tip 18a reaches the welded portion while making light contact with the power supply portion 25a of the pressed out portion of the ceramic sleeve 21a.

In this case, since the current-carrying tip 18a is arranged so as to lightly press the wire 3f as close as possible to the outlet of the ceramic sleeve 21a, the wire 3f is not deformed and bent by the current-carrying tip 18a. Due to the sufficiently high rigidity of the wire 3f, the displacement of the distal end of the wire 3f caused by pressing the wire 3f with the energizing tip 18a is larger than the displacement caused by the lateral movement of the wire 3f in the guide hole 2f of the ceramic sleeve. Does not grow.

The arc current is applied to a torch tip member 16 connected to a torch body (not shown) by a screw 17a.
a, the U-shaped groove 22a of the torch tip member 16a
Then, the current enters the current-carrying chip 18a through the contact current-carrying portion 24a between the current-carrying chip 18a and the current-carrying chip 18a having one end thereof, and flows to the arc forming portion through the wire 3f contacted by the power supply portion 25a.

The current-carrying tip 18a is lightly pressed against the wire 3f by the leaf spring 19a and is in contact therewith. There is no gap between the wire 3a and the guide hole 2a of the tip shown in the conventional tip 1a in FIG. Even if 3f is straight, the power supply tip 18a is always connected to the wire 3 by the force of the spring 19a.
Since the contact current is applied by pressing against f, arc breakage due to poor energization does not occur.

At the tip of the current-carrying tip 18a shown in FIG.
If the length b of the portion in contact with the wire is too long, the contact current-carrying point of the wire 3f varies therein. Then, the length of the wire from the current-carrying point to the arc generating point, that is, the effective wire extension changes, which causes a change in the arc length and the arc current, and changes the welding state, which is inconvenient. In order to avoid such inconvenience, it is necessary to set the length b to 5 mm or less. Conversely, if the length b is too short, wear progresses quickly and the chip life is shortened. In this embodiment, it is 3 mm.

FIG. 5 shows the shape of the conductive tip 18a at the beginning of use and the state of contact with the wire 3f. FIG. 6 shows the state of contact between the current-carrying tip 18a and the wire 3f after use for a long time. The current-carrying tip 18a is rubbed by the wire 3f and is worn and dug. Even if the wear progresses in this way, as long as the energizing tip 18a is pressed against the wire 3f by the leaf spring 19a, that is, as long as the gap a in FIG. 4 exists, the contact energization is performed stably. Life is significantly extended. When the service life has expired, the current-carrying tip 18a can be easily attached and detached because it is only held down by the spring 19a, and automatic replacement can be easily performed using a dedicated jig.

When the wire guide hole 2f of the ceramic sleeve 21a is a round hole, for example, for the wire 3f having a diameter of 1.2 mm, unless the inner diameter is set to about 1.4 mm or more,
Foreign matters such as copper plating wire scraps, wire cuttings, and dust conveyed to the wire 3f accumulate at the entrance side of the ceramic sleeve 21a, and the ceramic sleeve 2
1a, the wire 3f is sandwiched between the wires 3f, which causes clogging and makes the expensive ceramic sleeve 21a unusable. Therefore, the diameter of the round hole is set so that the wire 3f has a freedom of moving in the horizontal direction by 0.2 mm or more.

On the other hand, in the case of a regular triangular hole having an inscribed circle of 1.24 mm, the maximum value at which the wire 3f can freely move in the lateral direction is 0.07 mm, but the diameter 0 is formed at the three corners of the triangle. A large space through which a .44 mm spherical foreign matter can pass is formed, and foreign matter such as plating dust is removed from the wire 3f.
When the wire guide hole 2f of the ceramic sleeve 21a is formed into a triangular hole, no clogging occurs.

Further, since the ceramic sleeve 21a is made of a non-conductive ceramic having excellent wear resistance, it does not spark and wear as in the case of the conventional copper chip for GMA. Even when used for a long time, the ceramic sleeve 21a is hardly damaged by wear and has a very long life. When the sleeve is conductive, current flows through the wire 3f from both the sleeve and the conductive tip 18a, and the ratio of the current entering the wire 3f from each becomes unstable. The effective extension becomes unstable, and the arc length and the welding current change, so that the welding state becomes unstable. Therefore, when the nonconductive ceramic sleeve 21a is used, the wire current is supplied only from the current-carrying tip 18a side, and there is an effect that the effective extension is stabilized.

In this embodiment, a ceramic sleeve having a length of 30 mm is used.
Before entering, even if the wire 3f comes into contact with the torch tip member 16a or the screw 17a and conducts electricity therefrom, due to the electric resistance of the wire between the conducting point and the conducting point by the conducting tip, the conducting Because the percentage of current flowing from the chip is high, the variation in effective extension is not large enough to be problematic. Further, since the triangular hole 2f is used to reduce the lateral movement distance of the wire without causing clogging, the position variation of the wire sending point can be reduced, and the wire 3f having a bending habit is sent from the ceramic sleeve 21a. Since the inclination at the time of the arc is smaller, the fluctuation of the position of the tip of the wire, which is the arc generating point as a result thereof, is further reduced.

A characteristic feature is that even if the tip 18a is worn, the variation of the tip of the wire 3f is determined mainly by the state of the guide hole 2f of the ceramic sleeve 21a, and therefore may vary with time. And always remain at the initial small value.

Second Embodiment Next, a second embodiment of the torch for arc welding according to the present invention will be described with reference to the drawings. FIG. 12 is a plan view of the periphery 15b of the torch tip according to the embodiment of the present invention, and FIG. 13 is a central sectional view of FIG. 12, in which the schematic dimensions are almost the same as in the first embodiment. FIGS. 14 and 15 show details of the torch tip member 16b. The U-shaped groove 22a shown in FIGS.
I have to.

FIG. 16 is a plan view and FIG.
As shown in the side view of FIG. 10, the current-carrying tip 18b has one projection in FIG. 10 showing the current-carrying chip of the first embodiment,
The groove 27 has a concave shape. In addition, in the energizing tip 18b, the pin portion 28 is provided, and the pin groove 29 corresponding to the torch tip member 16b side is provided and inserted into the form.
This prevents the conductive tip 18b from shifting in the lateral direction.

As compared with the first embodiment, the contact area between the current-carrying tip and the tip member is increased in the lateral direction, so that the contact area is increased, so that the electrical conductivity and thermal conductivity there are improved. .

Third Embodiment A third embodiment of the torch for arc welding according to the present invention will be described with reference to the drawings. FIG. 18 is a plan view of a torch tip portion 15c around the tip of the torch according to the present invention, and FIG. 19 is a central sectional view of FIG.
mm (from the screw 17c to the tip of the current-carrying tip 18c).

In FIGS. 18 and 19, reference numeral 16c denotes a torch tip member of approximately 10 mm × 15 mm × 30 mm made of chromium copper.
7c, it is a conductor that conducts an arc current from the torch body, and also a heat conductor that transmits heat to the water-cooled torch body.

In the torch tip member 16c, an insulating Teflon liner 31 for guiding the wire 3h to the ceramic chip 30 as a ceramic guide member from the torch main body (not shown) is inserted. Is reduced, and it is also useful to specify the energized position so that the wire 3h is energized only from the energizing tip 18c.

A triangular hole 2h made of silicon nitride having an outer diameter of 10 mm and a length of about 45 mm is provided on the wire exit side of the torch tip member 16c.
Are screwed. As in the first embodiment, the torch tip member 16c is provided with a U-shaped groove 22c in the lateral direction, into which the current-carrying tip 18c is inserted and hooked. The current-carrying tip 18c has a wire 3h coming out of a ceramic chip 30 having a triangular hole at the tip of the torch tip member 16c.
Is pressed by a leaf spring 19c.

Accordingly, the wire 3h is connected to the torch tip member 1 by the screw 17c connected to the not-shown torch main body.
After passing through the liner 31 in 6c and beyond the tip of the ceramic chip 30, it comes into contact with the current-carrying tip 18c pressed by the leaf spring 19c and reaches the welded portion. The arc current passes through the current-carrying tip 18c fitted into the U-shaped groove 22c of the torch tip member 16c connected to the torch main body (not shown) by the screw 17c and flows into the welding portion by contacting the wire 3h at the power supply portion 25c. .

The current-carrying tip 18c is lightly pressed against the wire 3h by the leaf spring 19c. Even if there is no bend in the wire, the current-carrying tip 18c is always in contact with the current, so that arc breakage due to poor current-carrying does not occur. Since the wire 3h comes out of the ceramic chip 30 having the triangular hole 2h with a small amount of lateral movement, the displacement of the tip of the wire becomes smaller.

In a conventional ordinary torch, since there is electrical contact with the wire even in a portion other than the current-carrying tip, arc breakage is less likely to occur when a momentary contact failure occurs in the current-carrying tip. Was helpful in becoming. Therefore, if the wire is guided to the vicinity of the chip with an insulating Teflon liner in order to reduce the wire feeding resistance, there is a problem that arc breakage is likely to occur.

In the present embodiment, however, the wire 3h is brought close to the torch tip member 16c by the insulating Teflon liner 31.
Even if the wire feed resistance is reduced by guiding the contact, the contact energization by the energizing tip 18c is always performed, so there is no problem that instantaneous arc breakage occurs. In this way, a part of the wire current does not flow into the wire 3h from the point where the wire 3h comes into contact with a charged portion such as the torch main body or the guide hole of the screw 17c, so that the effective extension is kept constant. This has the effect of stabilizing the melting state, eliminating damage due to energization inside the torch, and prolonging the service life of the torch body and the torch tip member 16c.

When this embodiment is compared with the case of the first embodiment, the ceramic member becomes thicker and more expensive to secure the strength, but the structure is simpler and smaller, and the ceramic is exposed, There is an advantage that spatter is less likely to adhere.

Fourth Embodiment An example of application to a torch for hot wire TIG welding as a fourth embodiment according to the present invention will be described with reference to the drawings. FIG.
0 is a plan view of the torch part according to the present invention, and FIG. 21 is a side view thereof. 20 and 21, the torch tip member 16d is fixed to the tip of the copper tube 32 for guiding the wire 3i and conducting the wire current with a screw (not shown). A leaf spring 19d for holding down the energizing tip 18d-1 is fixed to the torch tip member 16d with a screw 23d-1.
A screw 23 for fixing a ceramic chip 30d as a ceramic guide member is provided on the tip side of the torch tip member 16d.
It is fixed at d-2.

With such a structure, the hot wire TI
During the G welding, the wire 3i passes through the copper tube 32, the torch tip member 16d, and the ceramic chip 30d and reaches a base material (not shown), but a wire current supplied from a wire heating power source (not shown). Flows through the path of the copper tube 32, the torch tip member 16d, the conducting tip 18d-1, the wire 3i, and the base material (not shown). Ceramic chip 30
Immediately before entering d, the current-carrying tip 18d-1 is pressed against the wire 3i by the spring 19d.

In this embodiment, the ceramic chip 30d
A ceramic chip having a triangular hole having an inscribed circle close to the wire diameter was used. The wire gradually rises in temperature due to resistance heating and is heated to the ceramic sleeve outlet, for example, to around 900 ° C for mild steel wire, but the straightening of a thin straight hole is passed through the softened wire to correct the wire bending habit. doing. FIG. 2 for the same effect
Compared with the torch structure of No. 8, the structure is simplified and extremely small.

FIG. 22 shows a current-carrying chip 18d according to the fourth embodiment.
FIG. 13 is a perspective view showing a structure of a current-carrying tip 18d-2 having a different structure instead of -1 and a thin copper tube 33-1 through which cooling water flows to one end side (a side in contact with the torch tip member 16d) of the current-carrying tip 18d-2. , 33-2 to allow the cooling water to pass through the current-carrying tip 18d-2. The current-carrying chip 18d-2 has a complicated structure and is expensive, and is inferior in that it takes time to replace the chip. However, it is possible to prevent the temperature of the current-carrying chip from increasing when a large current is supplied, and to extend the chip life. .

Other Embodiments The current-carrying chips 18a to 18d of the first to fourth embodiments are
Although the entire current-carrying chip is made of inexpensive chromium copper, a material such as copper tungsten or silver tungsten which is less worn by contact current may be used. However, in that case, the material cost increases. FIG. 23 shows an embodiment of an energizing tip 18e in which a copper tungsten member 34 is embedded and fixed as a contact energizing member at a position corresponding to the CC section of the energizing tip 18a in FIG. 1 of the first embodiment. The contact energizing member 34 may be a member in which a copper tungsten rod is inserted from the side and fixed. This makes it possible to construct a current-carrying chip having a longer life at a relatively low cost.

In the first and second embodiments, the ceramic sleeve 21 is used. In the third and fourth embodiments, the ceramic chip 30 is used.
Although silicon nitride was used for these, they are not limited to silicon nitride, and any other non-conductive ceramics, such as alumina, which has excellent wear resistance and can be substituted.

The holes through which the wires of the ceramic sleeve 21 and the ceramic chip 20 pass are most effective in the case of an equilateral triangle. However, the shape is not limited to an equilateral triangle. There may be. Further, as a shape resembling a triangle, a combination of a V-shaped groove and a flat plate can be used. In this case, although the torch structure is somewhat complicated, special equipment is required for manufacturing the triangular hole ceramic chip, but there is an effect that the manufacturing of the ceramic member becomes easier.

As described above, a feature of the embodiment of the present invention is that one end of the current-carrying tip in the welding torch is pushed by a spring against the current-carrying member, and the other end moves with the point as a fulcrum. The other end of the current-carrying tip is configured to be pressed by a spring and contact the wire from the side, and the current is supplied from the current-carrying member to the wire via the current-carrying tip.

In particular, in the case of a consumable electrode arc, a wire guide made of a heat-resistant, wear-resistant and electrically insulating ceramic is arranged in the torch, and immediately after the wire comes out of the ceramic guide, it comes into contact with the current-carrying chip. It is configured as follows.

When a ceramic guide is used in hot wire TIG welding, a heat-resistant, wear-resistant and electrically-insulating ceramic wire guide is arranged in a torch, and the wire guide is formed immediately before the wire enters the ceramic guide. It is configured to be in contact with the conducting chip.

If these ceramic guides are provided with a triangular hole or a triangular hole formed by a V-shaped groove and a flat plate member, the effect is more remarkably achieved.

[0065]

According to the present invention, the current-carrying tip has a structure that can be used even if it is considerably worn, so that its life is extended. The use of copper tungsten or the like for the power supply portion of the current-carrying chip could further extend the life.

The ceramic sleeve and the ceramic chip are somewhat expensive because they use ceramics having excellent wear resistance such as silicon nitride, but they are quasi-consumables that hardly wear and do not require daily replacement. Since the wire is guided by the triangular hole, no clogging occurs in the ceramic sleeve.

Also, the current-carrying tip as a consumable is about 1/5 or less the weight of the conventional current-carrying chip, so that the material cost is low, and the shape is simple and can be easily manufactured by forging. Manufacturing costs are halved.

The current-carrying chip can be easily taken out by sandwiching the chip from both sides even when the wire is left from the torch, and can be mounted, so that an automatic exchange device can be easily constructed.

In the conventional tip in GMA welding, instantaneous arc breaks often occur, and a large amount of spatter occurs when subsequently re-igniting. However, according to the torch of the present invention, the current-carrying tip is always used. Since the current is kept in contact with the wire, the generation of spatter due to such a cause is eliminated, and as a result, the spatter generation amount is greatly reduced.
Further, since the contact current is extremely good, the occurrence of arc start mistake, which has been a problem particularly in unmanned welding lines, has almost disappeared.

In the case of GMA welding, since a ceramic member having a narrow triangular hole is used to more restrict the lateral movement of the wire, the displacement of the tip of the wire has no relation to the abrasion state of the current-carrying tip and changes with time. I no longer have to. And since the position fluctuation at the wire delivery point from the welding torch is smaller, and the inclination of the wire having a bending habit at the wire delivery point is restrained to be smaller, the positional deviation of the wire tip is the same as the conventional one. It has decreased to about 1/2. At the same time, it is no longer necessary to impart a bending habit to the wire in order to secure electrical conductivity, so that the wire can be straightened and fed. By these,
In most cases, the problems of the occurrence of meandering beads during welding and the misalignment of the arc aiming position, which have been problems in the past, can be solved in most cases.

With these effects, and because the current-carrying tip has a structure that can be easily exchanged automatically, the occurrence of wire misalignment due to wear of the tip, which has been a problem with welding robots, and unexpected welding due to clogging of the tip. Since the occurrence of line stoppage due to stoppage and the like is extremely reduced, the use of the welding torch according to the present invention can provide a great effect particularly in the operation of an unmanned welding line.

In the case of hot wire TIG welding, the guide hole of the ceramic chip can be used in a state where the wire feed resistance is low and the electric conductivity is good, and a wire that requires the use of a narrower guide hole is required. Bending correction has also become easier.

As described above, the torch according to the present invention fundamentally solves the basic problem of the current-carrying tip in conventional GMA welding and the basic problem of using a ceramic guide in hot wire TIG welding. It has a great industrial effect.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of an arc welding torch according to the present invention.

FIG. 2 is a central sectional view of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a sectional view taken along the line CC of FIG. 1;

FIG. 6 is another example of a cross-sectional view taken along the line CC of FIG. 1;

FIG. 7 is a plan view of the torch tip member of FIG. 1;

FIG. 8 is a side view of the torch tip member of FIG. 1;

FIG. 9 is a plan view of the conductive chip of FIG. 1;

FIG. 10 is a side view of the conducting chip of FIG. 1;

FIG. 11 is a rear view of the current-carrying chip of FIG. 1;

FIG. 12 is a plan view showing a second embodiment of the arc welding torch according to the present invention.

FIG. 13 is a central sectional view showing a second embodiment of the torch for arc welding according to the present invention.

FIG. 14 is a plan view of the torch tip member of FIG.

FIG. 15 is a side view of the torch tip member of FIG.

FIG. 16 is a plan view of the conducting chip of FIG. 12;

FIG. 17 is a side view of the conducting chip of FIG. 12;

FIG. 18 is a plan view of an arc welding torch according to a third embodiment of the present invention.

FIG. 19 is a central sectional view of a third embodiment of the torch for arc welding according to the present invention.

FIG. 20 is a plan view of a fourth embodiment of the welding torch according to the present invention.

FIG. 21 is a side view of a fourth embodiment of the welding torch according to the present invention.

FIG. 22 is a diagram illustrating another embodiment of the current-carrying chip according to the present invention.

FIG. 23 is a diagram illustrating another embodiment of the current-carrying chip according to the present invention.

FIG. 24 is a sectional view of a conventional welding tip.

FIG. 25 is a view for explaining the shape of a guide hole of a current-carrying chip according to Japanese Patent Application Laid-Open No. 6-304761.

FIG. 26 is an explanatory view of a current-carrying chip according to Japanese Patent Application Laid-Open No. 64-18582, which is a prior art.

FIG. 27 is an explanatory view of a conventional welding torch.

FIG. 28 is an explanatory diagram of a welding torch according to Japanese Patent Application Laid-Open No. 7-236974, which is a prior art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Current-carrying tip 2 Guide hole 3 Wire 4 Tip outlet 5 Contact current-carrying point 6 Spring 7 Press-contact slider 8 Ceramic guide 9 Torch body member 10 V-groove wire guide 11 Screw 12 Current-carrying tip 13 Current-carrying cable 14 Ceramic holder 15 Torch tip Around the part 16 Torch tip member 17 Screw 18 Current-carrying tip 19 Leaf spring 20 Guide hole 21 Ceramic sleeve 22 Groove 23 Holding screw 24 Current-carrying part 25 Power feeding part 26 Projection 27 Groove 28 Pin 29 Pin groove 30 Ceramic chip 31 Teflon liner 32 Copper tube 33 Copper tube 34

Claims (6)

[Claims] 1. A torch tip member through which a wire is inserted, an energizing tip which contacts the wire and energizes the wire,
An elastic member that presses the current-carrying tip toward the wire side, wherein the current-carrying tip is pressed by the elastic member, and one end side or near one end side of the contact tip contacts the torch tip member. And the other end side contacts the wire from a substantially vertical direction in the wire length direction, and the wire is energized from the torch tip member via the energizing tip. And welding torch. 2. The welding torch according to claim 1, wherein a ceramic guide for guiding the wire is provided inside the torch tip member. A welding torch wherein the other end contacts the wire. 3. The welding torch according to claim 1, wherein a ceramic guide for guiding the wire is attached to an end of the torch tip member, and immediately before the wire is inserted from the torch tip member into the ceramic guide. A welding torch characterized in that the one end side of the current-carrying tip abuts on the torch tip member. 4. The welding torch according to claim 1, wherein a ceramic guide for guiding the wire is attached to an end of the torch tip member. A welding torch, wherein an end side contacts the wire. 5. The welding torch according to claim 2, wherein the ceramic guide has a triangular hole through which the wire is inserted. 6. The welding torch according to claim 2, wherein the ceramic guide comprises a V-shaped groove and a flat plate member through which the wire is inserted.