JPH0224633B2 - - Google Patents

Description

TECHNICAL FIELD The present invention relates to a welding torch that uses a welding wire as a consumable electrode.

Prior Art Generally, when using a consumable electrode, power is supplied to the electrode through a contact member that comes into contact with the electrode, but since the contact member is subject to severe wear, a long-life electrode is desired. To deal with this, conventional
For example, those shown in FIGS. 1 to 3 have been proposed. That is, first and second wear-resistant guide members 3a and 3b are arranged in an electrode passage spaced apart from each other, and one of the electrode passages between the guide members 3a and 3b has a thickness equal to or less than the electrode width. A contact member 7' and guide block 3 are provided with a wear-resistant guide block 3c and have a thickness exceeding the electrode width.
Welding was performed by holding the electrode between the electrodes 25 and 25 and feeding the electrode while supplying power to the electrode 25 through the contact member 7'. For this reason, as shown in FIG. 2, even if the contact member 7' wears out, only a deep groove is created, and welding work can be carried out without any problem.

By the way, in arc welding work, a so-called stick phenomenon often occurs in which the tip of the electrode adheres to the workpiece at the time of starting the arc or during the welding work. In this case, the contact member 7' and the electrode 25
Resistive heat generation indicated by I ² R occurs between the contact position, that is, the power supply position and the welding position of the electrode tip, and the electrode becomes extremely soft. Note that, for example, although short-circuit current is detected and the feeding of the electrode is stopped as appropriate, it is unlikely that the feeding of the electrode is stopped immediately when the tip of the electrode is welded to the object to be welded. That is, even after the tip of the electrode is welded, the electrode is still being fed to the object to be welded to some extent in an extremely weakened state. In the above case, as shown in FIG. 1, since the second wear-resistant guide member 3b is disposed at the tip of the contact member 7' and the electrode 25, The extremely weakened electrode that is fed to the workpiece side from the position is connected to the second wear-resistant guide member 3b as shown by the two-dot chain line in FIG.
The electrode appears to be embedded in the hole, and feeding of the electrode is often stopped in this state. Normally, the electrode tip is automatically or manually cut off due to the occurrence of the stick phenomenon, and then restarted. However, as described above, since the electrode is embedded in the hole of the second wear-resistant guide member 3b, the electrode cannot be fed toward the object to be welded. For this reason, for example, it was necessary to pinch the tip of the electrode with pliers or the like and forcibly pull the electrode in the _X1 direction to push out the swaged electrode portion. Moreover, the distance between the tip of the passage welding torch and the workpiece is 10~
Since it is selected to be about 30mm, the torch must be sufficiently retracted in order to pull the above electrode in the _X1 direction.
Workability was also poor. Furthermore, sintered porcelain, which has good wear resistance and heat resistance, is commonly used as guide members, but the mechanical strength of this sintered porcelain is not very high, and for this reason, as mentioned above, the sintered porcelain is When removing the electrode portion, the guide member may be damaged, which is not only economically disadvantageous, but also requires replacing the guide member, which is troublesome. Furthermore, in arc welding operations using consumable electrodes, particles of high-temperature molten metal, so-called spatter, are generally scattered, but with a welding torch having the structure shown in Figs. Since spatter enters the path of the electrode wire and the sliding groove of the contact member through the opening, there is a risk that the feedability of the electrode wire and the movability of the contact member will be inhibited. In addition, in the above-mentioned conventional torch, it is possible to provide a cover to prevent spatter from entering the electrode wire passage and the sliding groove of the contact member, but in this case, a cover suitable for the narrow part may be manufactured. However, if a cover is provided, maintenance of the torch tip may be difficult and workability may be impaired. In addition, when performing shield gas arc welding using the conventional torch mentioned above, the tip of the torch becomes large, making it impossible to weld in narrow areas, and creating a passageway for supplying shield gas to the welding area. It was difficult to do so.

Purpose of the Invention The present invention has been made in view of the above problem, and is provided with a passageway for maintaining a stable shielding gas flow without impeding the feeding of the electrode wire due to sputtering. Therefore, it is an object of the present invention to provide a welding torch which has a compact structure and is easy to work with, and can restart welding by cutting off the electrode tip when the electrode tip is welded to a workpiece.

Embodiments The present invention will be described in detail below with reference to illustrated embodiments. In FIGS. 4 to 7, 1 is a torch body with a through hole 101 bored in the axial center, and 2 is a wear-resistant guide tube detachably disposed in the through hole 101, for example, approximately at the axial center. A hole with a circular cross section is bored in the part. 3 has a through hole 30 approximately at the shaft center.
1 is a wear-resistant guide block with a hole, for example, this guide block 3 is attached to the torch body 1.
It is screwed onto the end in the _X1 direction. The torch body 1, guide tube 2 and guide block 3 constitute a fixed guide member 4 for guiding the electrode wire 25. 5 is a cylindrical support member; 6 is a power feeding member having a through hole 601 formed approximately in the axial center and a bottomed hole 602 opening in the _X2 direction; for example, this power feeding member 6 is It is screwed onto the end of the support member 5 in the _X1 direction.
The support member 5 and the power supply member 6 constitute a contact member 7, and the contact member 7 is made of a highly conductive material, such as copper or a copper-based alloy. The free end of the fixed guide member 4 is inserted inside this contact member 7 . Torch body 1
A flange portion 102 is disposed on the base side of the power supply connecting member 11 and an intermediate member 12, and the flange portion 102 is held between the power supply connecting member 11 and the intermediate member 12 via appropriately shaped insulating members 8 and 9. The support member 5 that supports the power supply member 6 and the intermediate member 12 are connected by a flexible connection member 13, for example, a cylindrical braided wire made of copper or a copper-based alloy. Further, the cylindrical body 14 consisting of 141 and 142 includes the intermediate member 12, the flexible connecting member 13, and the contact member 7.
The torch body 1 is supported on the base side of the torch body 1 so as to cover the base side of the torch body 1 . Further, the support member 5 is rotatably supported by the cylindrical body 14. For example, as shown in FIG. 5, the second cylindrical body 142 is formed of an electrically insulating member, and the second cylindrical body 142 and the support member 5 are rotationally supported by opposing support pins 15. ing. The support member 5 is positioned in the Z direction by contacting the opposing surfaces 151, 151 of the support pin 15. 16 is an elastic airtight member, for example an "O" ring. The torch body 1 is appropriately supported by a mounting member 18 via an electrically insulating member 17 disposed in the _X2 direction. Reference numeral 19 denotes a pressurizing means, for example, one end of a leaf spring 191 is supported by the torch body 1 by a supporter 192, and the other end of this leaf spring 191 is supported by the support member 5.
A pressurizing means 19 is configured so as to be in contact with an electrically insulating member 193 disposed in the . 21 is the support member 5
The gas nozzle 21 is detachably supported at the free end of the gas nozzle 21. For example, the gas nozzle 21 is composed of an electrically insulating nozzle 211 and a metal nozzle 212. The gas nozzle 21 and the contact member 7 are integrally urged by the pressure means 19 in the counterclockwise direction in FIG. 4 about the support pin. Reference numeral 22 indicates one or more drilling holes provided in the guide member 4; 23 indicates two or more, for example, four, drilling holes provided at approximately equal intervals in the radial direction around the support member 5; The passage of the electrode wire 25 and the internal space of the gas nozzle 21 are communicated through the perforated holes 22 and 23 and the cylindrical space 24. Reference numeral 110 denotes a hole drilled in the power supply connecting member 11, and the power supply connecting member 11 and a power supply tool (not shown) are connected through the drilled hole 110.

In the above configuration, after the electrode wire 25 is fed and reaches the perforation hole 601 of the power feeding member 6, the contact member 7 is fed through a power feeding tool (not shown).
and supplies shielding gas to the gas nozzle 21.
Welding is performed by feeding the electrode wire 25 while making it flow out more. In the illustrated case, the shielding gas is fed through the passage of the electrode wire 25 and flows out into the gas nozzle 21 through the perforation 22, the cylindrical space 24, and the perforation 23.

In this case, the contact member 7 is pressed by the pressure means 19.
Since it is biased in the _Y2 direction, the tip of the contact member 7 rotates counterclockwise in FIG. 4 about the support pin 15 and comes into contact with the electrode wire 25. That is, by a feeding device (not shown)
The electrode wire 25 fed in the _X1 direction is restrained by the guide block 3 and fed to the welding position while making sliding contact with the tip end member of the contact member 7, that is, the power feeding member 6. By the way, as welding progresses, the portion of the power feeding member 6 corresponding to the power feeding position gradually wears out.
Since the power supply member 6 supported by the support member 5 is urged in the _Y2 direction by the pressure means 19, the power supply member 6 and the electrode wire 25 are always in contact with each other regardless of wear of the power supply member 6. This ensures that power is supplied in a steady state. Moreover, the gas nozzle 21 is supported by the free end of the contact member 7, and the gas nozzle 21 and the contact member 7 rotate integrally around the support pin 15, so that regardless of the wear of the power supply member 6, The cylindrical space 26 defined by the gas nozzle 21 and the contact member 7 is always maintained in a constant shape. If the cylindrical space 26 within the gas nozzle 21 is maintained in a constant state in this manner, the ejection flow of the shielding gas is also maintained constant, and uniform welding can be performed. Note that since the electrode wire 25 is restrained by a fixed guide member, especially the guide block 3, it is fed to a fixed position in the Y direction regardless of whether the power feeding member 6 is worn out. As the member 6 wears, the gas nozzle 21 and the contact member 7 become _Y2 centering around the support pin 15.
There is a concern that the axis of the electrode wire 25 and the axis of the jet flow of the shielding gas flowing out from the gas nozzle 21 may not coincide with each other. However, generally the distance between the power supply member 6 and the workpiece to be welded is 10
The shielding gas, which is selected to be approximately 30 mm and is ejected from the gas nozzle 21, is an annular laminar flow,
Since it is sprayed over a relatively wide area including the welding point,
Even if the axis of the ejected flow of the shielding gas does not match the axis of the electrode wire, the gas shielding effect does not substantially change. Furthermore, as the welding progresses, the through hole 601 of the power supply member 6 gradually becomes Y ₁
Since the wear occurs in the direction, a space is created above the through hole 601, that is, in the _Y2 direction, corresponding to the amount of wear.
As this space becomes larger, spatter generated during arc welding may fly in the _X2 direction, but since the electrode wire 25 is always fed in the _X1 direction during welding work, the spatter is
5 is carried outward from the upper space of the through hole 601. Furthermore, since power is supplied while the approximately semicircular portion of the through hole 601 in the _Y1 direction is constantly in sliding contact with the electrode wire 25, spatter cannot enter this power supply portion. It should be noted that it is advantageous if at least the tip of the power feeding member 6 is formed into a spherical convex shape, since it is difficult for spatter to adhere to the spherical convex shape, and even if it does, it is easily removed. It can also be

In this way, there is no possibility that the spatters will adversely affect the power supply state, and since the guide member 4 is covered with the contact member 6, the cylindrical body 14, etc., the spatters will enter the feeding path of the electrode wire 25. There's nothing to do.

In this way, spatter does not impede the feedability of the electrode wire or deteriorate the power supply condition, and even if the contact members are slightly worn, welding can be performed in the same state as the initial state, so welding can be continued for a long time. Uniform welding can be performed over the entire area,
Therefore, it is particularly effective for automatic welding.

Note that when the tip of the electrode wire is welded to the workpiece at arc start or during welding work, the electrode wire is fed to the workpiece to some extent as described above. In this case, in the torch according to the present invention, no problem occurs because the contact member 6 can be rotated as appropriate about the support pin 15 as described above. In addition, since a conventional wear-resistant guide member is not disposed closer to the object to be welded than the power supply position, the melting electrode does not swamp as in conventional torches.
Therefore, when the electrode wire is welded to the object to be welded, the welding operation can be resumed immediately by simply cutting the tip of the electrode wire appropriately, resulting in good workability. Furthermore, since the support member 5 is positioned in the Z direction by contacting the opposing surfaces 151, 151 of the support pin 15, power is supplied in a steady state in conjunction with the arrangement of the guide block 3.

8 to 11 are diagrams showing other embodiments of the present invention, in which the power supply connecting member 11 and the cylindrical body 1
4 and 4 are positioned relative to each other by a rotational positioning tool 271 such as a key material, and are integrally supported by a fastening tool 281 such as a nut. Further, the intermediate member 12 and the cylindrical body 14 are positioned relative to each other by a rotational direction positioning device 272, such as a key material, and are integrally supported by a fastening device 282, such as a cap nut. The torch body 1 is inserted through the approximate axis of the intermediate member 12 and is supported integrally with the intermediate member 12 by a fastener 283, for example, an adapter screwed onto the end of the intermediate member 12 in the X ₂ direction. . Reference numeral 29 denotes a groove provided on the outer periphery of the base side of the torch body 1, and this groove 29 communicates with grooves 291, 291 extending in the axial direction provided on the outer periphery of the torch body 1.
and a cylindrical space 24 formed by the support member 5. 31 is, for example, the power supply connecting member 1
This connection port 31 and the groove 29 provided on the outer periphery of the torch body 1 are connected to a perforation hole 32 that passes through an appropriate member.
It is communicated by. Further, the support member 5 is rotatably supported by a support pin 15 at the free end of the cylindrical body 14, that is, the end in the _X1 direction. In the illustrated case, the support pin 15 is preferably formed of an electrically insulating member. 192 is an electrically insulating bush screwed onto the cylindrical body 14; 193 is the bush 192;
A compression spring 191 is disposed between the adjustment screw 193 and the support member 5. In this case, after rotating the adjustment screw 193 to appropriately select the rotation force of the contact member 7 with respect to the support pin 15, the adjustment screw 19 is rotated by the nut 194.
3 is locked. Note that, as shown in the figure, since the airtight members 161, 162, 163 are appropriately arranged, the shielding gas supplied from the connection port 31 passes through the perforated hole 32, the grooves 29, 291, the cylindrical space 24,
After passing through the perforated holes 23, 231 and the annular space 26 of the gas nozzle 21, it flows out to the welding position. Of course, the groove 29 can also be provided on the inner circumference of the intermediate member 12.

With the configuration shown in FIGS. 8 to 11, the contact state between the electrode wire 25 and the contact member 7 can be finely adjusted even during welding.

In the above, the guide tube 2 may be formed into a substantially cylindrical body by a wire rod having an appropriate shape such as a round or rectangular cross section. Further, the cross-sectional shape of the electrode can be non-circular, for example, rectangular.

Furthermore, it is preferable to coat or cover the outer periphery of the guide tube 2 with an electrically insulating member to electrically insulate the consumable electrode wire 25 from the torch body 1. Furthermore, if a guide tube is provided, the electrode wire can be guided smoothly by replacing the guide tube with a new one as the guide tube wears out, and the guide tube, the guide member, and the power supply member can be attached and detached. If so, by replacing these with ones having suitable through holes for electrode wires, it is possible to realize welding torches that are compatible with electrode wires of various shapes. Despite this, the guide tube can be omitted as shown in FIG.

Note that if the torch body, support member, contact member, cylindrical body, etc. are appropriately forcibly cooled, each part of the torch will not become hot, making it easy to handle the torch and allowing the torch to be used for a long time.

Further, since the fixed guide member 4, contact member 7, and gas nozzle 21 are supported substantially coaxially, the tip of the welding torch can be made compact, and it can be applied to a narrow welded part.

Effects of the Invention As described above, according to the present invention, the contact member that rotates about the support pin with respect to the fixed guide member and the gas nozzle are integrally supported, so that power is supplied during welding work. Even if the welding member wears out, the ejected flow of shielding gas against the welding area provides the same gas shielding effect as in the initial state, and therefore uniform welding can be performed. Further, since the fixed guide member, the contact member, and the gas nozzle are arranged substantially coaxially, the welding torch, especially the tip end, can be made compact, and therefore it can be applied to narrow welded parts. Furthermore, since spatter does not enter the feeding of the electrode wire, there is no risk of impeding the feedability of the electrode wire, and power is fed while the electrode wire and the contact member are constantly in sliding contact with each other due to the pressurizing means. In addition, since the contact member is positioned in the Z direction by the support pin, power is supplied in a steady state, and the target position of the electrode is approximately constant, so welding can be performed reliably.
Furthermore, since the contact member can be rotated as appropriate and the contact member with the through hole 601 is made of a conductive material, when the tip of the electrode is welded to the object to be welded, There is no situation where the melting electrode becomes swamped like this, and therefore, during welding, welding can be restarted while feeding the electrode by simply cutting off the tip of the electrode, resulting in good work efficiency.

[Brief explanation of drawings]

Fig. 1 is a front sectional view of a main part showing a conventional example, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a state explanatory diagram of Fig. 1, and Fig. 4 shows an embodiment of the present invention. The front sectional views and FIGS. 5 to 7 are respectively shown at - in FIG.
8 is a front sectional view showing another embodiment of the present invention, and FIGS. 9 to 11 are sectional views taken along lines -, -, and XI-XI of FIG. 8, respectively. FIG. 1...Torch body, 4...Guide member, 5...
... Support member, 6 ... Power supply member, 7 ... Contact member, 13 ... Flexible connection member, 14 ... Cylindrical body, 15 ... Support pin, 19 ... Pressure means, 21
...Gas nozzle, 25...Electrode wire.

Claims (1)

[Scope of Claims] 1. A contact member is constituted by a power supply member having a through hole for a consumable electrode wire and a cylindrical support member that supports the power supply member, and a fixed guide member that guides the electrode wire. The free end of the contact member is inserted into the contact member, and the power supply connecting member disposed on the base side of the welding torch and the support member of the contact member are connected by a flexible connecting member, and welding is performed. A cylindrical body is provided that covers the flexible connecting member and the base side of the contact member from the base side of the torch, and opposing support pins arranged on the cylindrical body are used to form a plane including the axis of the electrode wire. The contact member is tiltably supported at the top, and the contact member is restrained and supported in a direction substantially perpendicular to the plane, a gas nozzle is removably supported at the free end of the support member of the contact member, and the base of the welding torch is A welding torch comprising a shielding gas passage extending from the side to the inside of the gas nozzle, and a pressurizing means for integrally urging the contact member and the gas nozzle toward the electrode wire side. 2. The welding torch according to claim 1, wherein the contact member is supported by coming into contact with opposing surfaces of the support pin. 3. The welding torch according to claim 1 or 2, wherein the power feeding member of the contact member has at least a tip portion formed in a spherical convex shape.