JP5448060B2 - Consumable electrode gas shield arc welding torch - Google Patents

Description

  The present invention relates to an improved consumable electrode gas shielded arc welding torch.

  Today, in order to improve the work efficiency of welding, it is widely performed to automate welding using a welding robot. In this case, a consumable electrode gas shielded arc welding torch (hereinafter referred to as a welding torch) is attached to the wrist of the manipulator of the articulated robot, and a welding wire wound around a wire reel is fed to the welding torch for electric power and shielding. Gas is supplied to the welding torch for welding.

  Since the welding wire fed to the welding torch is usually wound around a wire reel, the welding wire is bent. Since the bending curve of the welding wire is not constant, it is difficult to match the tip position of the welding wire sent from the power feed tip attached to the tip of the welding torch to the desired welding target position.

  In addition, power is supplied to the welding wire when the welding wire comes into internal contact with the power supply tip attached to the tip of the welding torch. If the bending of the welding wire is not constant, the contact point between the welding wire and the power supply tip Is not constant. As a result, the length from the contact point between the welding wire and the power feed tip to the tip of the welding wire varies. Due to this variation, the resistance heat generation of the protruding length portion of the welding wire varies, and the amount of melting of the welding wire varies. As a result, the arc length varies and a uniform weld bead cannot be formed.

  Therefore, in order to solve the above-described problems, the following forced pressurizing power supply torch has been proposed. FIG. 4 is a cross-sectional view of a prior art welding torch. In the figure, the feeding direction of the welding wire is X1, and the opposite direction is X2. A tip body 3 including a first tip body 3a and a second tip body 3b is attached to a tip portion (X1 direction) of the torch body 2 of the welding torch 1, and a tip holder 4 is attached to the tip portion of the tip body 3. ing. A heat-resistant member 5 made of ceramic is provided at the tip of the chip holder 4. These torch body 2, tip body 3, tip holder 4, and heat-resistant member 5 have wire insertion holes formed in the shaft core portion. In addition, the heat-resistant member 5 described above prevents power supply to the welding wire when the welding wire comes into contact with the wire insertion hole of the chip holder 4.

  A spring 6 is provided inside the torch body 2. The pressure shaft 7 is provided inside the tip body 3, and the proximal end portion (X2 direction) of the pressure shaft 7 is in contact with the distal end portion of the spring 6. The spring 6 and the pressure shaft 7 have a wire insertion hole formed in the shaft core portion. A distal end portion of a wire guide liner 14 that guides a welding wire fed from a wire feeding device (not shown) is inserted through the spring 6 and inserted into a proximal end portion of the pressure shaft 7.

  The power feed tip 8 has a wire insertion hole formed in the shaft core portion, and the base end portion (X2 direction) of the power feed tip 8 is inserted into the tip end portion of the second tip body 3b to The tip portion (X1 direction) of the power feed tip 8 is inserted into the tip holder 4. That is, the power feed tip 8 is pressed by the pressure shaft 7 and the tip holder 4. Further, the power feed tip 8 is formed with a vertical slit 9 extending from the tip portion along the wire insertion hole, and the thickness of the vicinity of the base end portion of the vertical slit 9 is reduced on the side surface of the power feed tip 8. The feeding chip 8 is easy to bend.

  Further, a taper shape 10 is formed on the side surface of the power supply chip 8 so as to contact an inclined surface formed at the base end portion of the chip holder 4. For this reason, since the vertical slit 9 is formed as described above, when the tip of the power feed tip 8 is inserted into the chip holder 4 and the power feed tip 8 is pressed by the pressure shaft 7 and the chip holder 4. The tip of the wire insertion hole 9 of the power supply tip 8 is reduced in diameter, and the inner surface of the wire insertion hole pressurizes the welding wire to supply power.

  An orifice 11 is provided below the first tip body 3 a, and a nozzle 12 surrounds the tip holder 4 and the orifice 11. Shielding gas is ejected through the ejection hole of the orifice 11, and this shielding gas shields the arc, the molten pool and the surrounding area from nitrogen and oxygen in the atmosphere. An insulating bush 13 is provided around the first chip body 3a. (For example, refer to Patent Document 1).

  The operation will be described below. A welding wire fed from a wire feeding device (not shown) is guided by the wire guide liner 14 and is inserted through the spring 6, the pressure shaft 7, the power feed tip 8 and the tip holder 4. The spring 6 presses the pressure shaft 7, and the power supply tip 8 is pressed by the pressure shaft 7 and the tip holder 4. At this time, since the vertical slit 9 is formed in the power supply tip 8, the inner surface of the wire insertion hole of the power supply tip 8 pressurizes the welding wire to supply power.

  Further, the electric power supplied to the torch body 2 flows through the chip body 3, flows into the chip holder 4, is supplied to the power feeding chip 8, and is supplied to the welding wire. Shielding gas is ejected through the ejection hole of the orifice 11, and this shielding gas shields the arc, the molten pool and the surrounding area from nitrogen and oxygen in the atmosphere.

International Publication No. WO2008 / 018594A1 Pamphlet

  In the conventional welding torch 1 described above, when the welding wire comes into contact with the wire insertion hole of the tip holder 4, a heat-resistant member 5 made of ceramic is provided at the tip portion of the tip holder 4 in order to prevent power supply to the welding wire. Is provided. As a result, since the welding wire is fed only by the feeding tip 8, the feeding point is stabilized and an appropriate welding bead can be formed. However, when the arc comes into contact with the heat-resistant member 5 made of ceramic or the wire burns up, the ceramic is easily welded and cracks due to heat. In addition, ceramic fragments that are cracked during welding may be mixed into the work piece, resulting in poor welding.

  An object of the present invention is to provide a welding torch that supplies power to a welding wire with a chip holder without providing a heat-resistant member made of ceramic at the tip of the chip holder.

The first invention is
Torch body,
A tip body attached to the tip of the torch body;
Attached to the tip of the chip body, without providing a heat-resistant member made of ceramic at the tip, all is made of metal, a hollow part is formed inside from the base end side, and a wire is formed at the tip A chip holder in which an insertion hole is formed and a welding wire comes into contact with the wire insertion hole and is fed;
Provided between the tip portion of the tip body and the tip holder, the tip portion is inserted into the hollow portion of the tip holder, a tapered shape is formed on the side surface of the tip portion, and a wire insertion hole in the shaft core portion Is formed, a vertical slit extending from the distal end portion along the wire insertion hole is formed, and a correction tip having a reduced thickness on the side surface of the base end portion of the vertical slit, and
A spring provided inside the torch body,
When the taper shape of the correction tip is pressed against the proximal end portion of the tip holder by the spring force of the spring, the wire insertion hole of the correction tip is reduced in diameter and pressurizes the welding wire. The taper shape is formed so that a distance is formed between the tip of the correction tip and the inner surface of the tip of the tip holder where the wire insertion hole is formed,
The welding wire comes into contact with the wire insertion hole of the correction tip and the wire insertion hole of the tip holder, the welding wire is corrected with the wire insertion hole of the correction tip, and the wire insertion hole of the tip holder A consumable electrode gas shielded arc welding torch that is supplied with power.

The second invention is
In the tip holder according to the first invention, a concave portion is formed at the tip,
A consumable electrode gas shielded arc welding torch characterized in that a conductive member made of copper tungsten or silver tungsten and having a wire insertion hole formed in an axial core portion is inserted into the concave portion and crimped.

  The welding torch according to the present invention corrects the bending wrinkles of the welding wire with a straightening tip and supplies power to the welding wire through the wire insertion hole of the tip holder. Since the heat-resistant member is not provided, the arc does not contact the ceramic, the wire burns up, the ceramic is welded, and the heat does not break. Also, there is no possibility of welding failure due to ceramic fragments cracked during welding mixed into the workpiece.

It is sectional drawing of the welding torch of Embodiment 1 of this invention. It is an exploded sectional view of the welding torch of Embodiment 1 of the present invention. It is sectional drawing of the chip holder of the welding torch of Embodiment 2 of this invention. It is sectional drawing of the welding torch of a prior art.

[Embodiment 1]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the invention will be described based on examples with reference to the drawings. FIG. 1 is a sectional view of a welding torch according to Embodiment 1 of the present invention, and FIG. 2 is an exploded sectional view of the welding torch according to Embodiment 1 of the present invention. 1 and 2, the tip holder 21 of the welding torch 20 is attached to the tip of the second tip body 3b, and all of them are formed of a metal having conductivity and good thermal conductivity such as a copper alloy. A hollow portion into which a distal end portion of a correction chip 23 to be described later is inserted is formed from the base end portion side (X2 direction), and a wire insertion hole is formed at the distal end portion. The welding wire comes into contact with the insertion hole to supply power. An inclined surface 22 is formed at the base end portion of the chip holder 21 so that a taper shape 24 of a correction chip 23 to be described later contacts.

  The straightening tip 23 has the same structure as that of the power feed tip 8 of the conventional welding torch 1 shown in FIG. For this reason, the straightening tip 23 can supply power to the welding wire in the same manner as the power supply tip 8, but normally a current flows from the side closer to the workpiece to be welded. Power is supplied by the holder 21. This straightening tip 23 is used to straighten the bending wrinkles of the welding wire. A distance is formed between the tip of the correction tip 23 and the inner surface of the tip holder 2 where the wire insertion hole of the tip holder 2 is formed. The taper shape 24 of the correction tip 23 is formed by the spring force of the spring 6. When pressed by the inclined surface 22 formed at the proximal end portion of the holder 21 and the wire insertion hole of the correction tip 23 is reduced in diameter to pressurize the welding wire, the taper is formed so that the above distance is formed. A shape 24 is formed. For other functions, the same functions as those in the conventional welding torch 1 shown in FIG.

  The operation will be described below. 1 and 2, a welding wire fed from a wire feeding device (not shown) is guided by a wire guide liner 14 and inserted through a spring 6, a pressure shaft 7, a correction tip 23 and a tip holder 21. To do. Then, when the pressing shaft 7 presses the correction tip 23 by the spring force of the spring 6, the taper shape 24 of the correction tip 23 is pressed against the inclined surface 22 of the tip holder 21. At this time, since the straight chip 25 is formed in the straightening tip 23, the inner surface of the wire insertion hole of the straightening tip 23 pressurizes the welding wire to correct the bending wrinkles.

  Further, the electric power supplied to the torch body 2 flows through the chip body 3 and flows into the chip holder 21, and the welding wire comes into contact with the wire insertion hole and is supplied with power. At this time, electric power is also supplied from the tip holder 21 to the correction tip 23 to be supplied to the welding wire, but usually a current flows from the side closer to the workpiece. Therefore, since the power supply to the welding wire is supplied by the tip holder 21, the power supply point to the welding wire is stable. Shielding gas is ejected through the ejection hole of the orifice 11, and this shielding gas shields the arc, the molten pool and the surrounding area from nitrogen and oxygen in the atmosphere.

  As a result, as described above, the welding torch according to the first embodiment of the present invention corrects the bending wrinkles of the welding wire with the correction tip 23 and supplies power to the welding wire through the wire insertion hole of the tip holder 21. Since the heat-resistant member 5 made of ceramic is not provided at the tip portion of the chip holder 21 as in the prior art, the arc may contact the ceramic, the wire may burn up and the ceramic may be welded, or may be broken by heat. Absent. Also, there is no possibility of welding failure due to ceramic fragments cracked during welding mixed into the workpiece.

  Moreover, since the ceramic manufacturing process provided in the tip holder 4 of the conventional welding torch 1 generally remains unprocessed after sintering, the dimensional error of the heat-resistant member is large, and the wire insertion hole The dimensional accuracy could not be increased. Further, since the heat-resistant member 5 made of ceramic is embedded in the tip end portion of the tip holder 4 of the conventional welding torch 1 for performing crimping, the wire insertion hole of the heat-resistant member 5 may be displaced from the axis of the chip holder 4. It has been difficult to improve the accuracy of the aim of the tip position of the welding wire with respect to the workpiece.

  On the other hand, the welding torch 20 according to the first embodiment of the present invention can improve the processing accuracy of the wire insertion hole by forming the tip holder 21 from the same material, so that the welding wire for the workpiece is welded. It is possible to reduce the deviation of the target position of the tip. In particular, when a pack wire housed in a pail pack is used as a welding wire, the spiral bend is greatly attached and the bend is not constant. Therefore, the welding torch 20 according to the first embodiment of the present invention is used. By this, the shift | offset | difference of the aim position of the front-end | tip of a welding wire can be reduced, and a high quality weld bead can be formed. Further, since the welding wire is straightened with the straightening tip 23, the contact of the wire insertion hole with the tip holder 21 becomes gentle, so that wear of the wire insertion hole is suppressed, and the life of the tip holder 21 is further increased. Can be stretched. Further, when discarding the used chip holder 21, it is not necessary to separate the heat-resistant member 5 as in the prior art.

  In addition, the welding torch 20 of Embodiment 1 of this invention may form all the chip holders 21 with carbon instead of forming the above-mentioned chip holder 21 with a copper alloy. In this case, it is possible to reduce the adhesion of spatter during welding to the chip holder 21.

[Embodiment 2]
FIG. 3 is a sectional view of the tip holder of the welding torch according to the second embodiment of the present invention. In the figure, a recess 32 is formed at the tip of the tip holder 31 of the welding torch 30, and the recess 32 is made of a material having heat resistance such as copper tungsten or silver tungsten and having wear resistance. The member 33 is inserted and crimped. The conductive member 33 has a wire insertion hole formed in the shaft core portion. The welding torch 30 according to the second embodiment of the present invention has the same function as that of the first embodiment shown in FIG. 1 except that the tip holder 21 of the welding torch 20 according to the first embodiment of the present invention is replaced with the chip holder 31 shown in FIG. Therefore, description of functions other than the chip holder 31 is omitted. Further, the operation of the welding torch 30 according to the second embodiment of the present invention is the same as the operation of the welding torch 20 according to the first embodiment of the present invention, and thus the description thereof is omitted.

  As a result, the welding torch 30 according to the second embodiment of the present invention is not provided with the heat-resistant member 5 made of ceramic at the tip portion of the tip holder 31 like the welding torch 20 according to the first embodiment of the present invention. The arc does not come into contact with the ceramic, the wire does not burn up and the ceramic is welded, and it does not break with heat. Also, there is no possibility of welding failure due to ceramic fragments cracked during welding mixed into the workpiece.

  Further, since the welding wire is straightened by the straightening tip 23, the contact of the wire insertion hole with the tip holder 31 becomes gentle, so that wear is suppressed and the life of the tip holder 31 can be further extended. Moreover, since the conductive member 33 formed of a heat-resistant and wear-resistant material is inserted into and crimped to the tip portion of the chip holder 31, the welding torch 20 according to the first embodiment of the present invention. Furthermore, the lifetime of the chip holder 31 can be further extended.

DESCRIPTION OF SYMBOLS 1 Welding torch 2 Torch body 3 Tip body 3a 1st tip body 3b 2nd tip body 4 Tip holder 5 Heat-resistant member 6 Spring 7 Pressurizing shaft 8 Feeding tip 9 Wire insertion hole 10 Taper shape 11 Orifice 12 Nozzle 13 Insulating bush 14 Wire Guide liner 20 Welding torch 21 Tip holder 22 Inclined surface 23 Straightening tip 24 Tapered shape 25 Vertical slit 30 Welding torch 31 Tip holder 32 Recess 33 Conductive member

Claims (2)

Torch body,
A tip body attached to the tip of the torch body;
Attached to the tip of the chip body, without providing a heat-resistant member made of ceramic at the tip, all is made of metal, a hollow part is formed inside from the base end side, and a wire is formed at the tip A chip holder in which an insertion hole is formed and a welding wire comes into contact with the wire insertion hole and is fed;
Provided between the tip portion of the tip body and the tip holder, the tip portion is inserted into the hollow portion of the tip holder, a tapered shape is formed on the side surface of the tip portion, and a wire insertion hole in the shaft core portion Is formed, a vertical slit extending from the distal end portion along the wire insertion hole is formed, and a correction tip having a reduced thickness on the side surface of the base end portion of the vertical slit, and
A spring provided inside the torch body,
When the taper shape of the correction tip is pressed against the proximal end portion of the tip holder by the spring force of the spring, the wire insertion hole of the correction tip is reduced in diameter and pressurizes the welding wire. The taper shape is formed so that a distance is formed between the tip of the correction tip and the inner surface of the tip of the tip holder where the wire insertion hole is formed,
The welding wire comes into contact with the wire insertion hole of the correction tip and the wire insertion hole of the tip holder, the welding wire is corrected with the wire insertion hole of the correction tip, and the wire insertion hole of the tip holder A consumable electrode gas shielded arc welding torch characterized by being fed. The chip holder according to claim 1, wherein a concave portion is formed at a tip portion thereof,
A consumable electrode gas shield arc welding torch characterized in that a conductive member made of copper tungsten or silver tungsten and having a wire insertion hole formed in an axial core portion is inserted into the concave portion and crimped.

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