JP2008290091A - Arc welding torch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an arc welding torch in which no spatters stick to the blow-off port of a nozzle and in which sure oxidation prevention is made possible near a weld zone. <P>SOLUTION: The arc welding torch is composed of: a nozzle body 4 that is attached to a nozzle body 2, with a tip 3 enclosed, and that makes a supplied shield gas flow outside from a gas feeding port 4d installed at the tip end; a nozzle cover 5 that is attached to a nozzle body 4 and that jets outside through an annular gas blow-off port 5d the shield gas supplied from the gas feeding port 4d; and a spatter guard 6 that is installed in the tip end of the nozzle body 4 with a welding wire 7 put through and having a guide hole 6a allowing the shield gas pass inside and jett outside, and that makes the shield gas jetted from the gas blow-off port 5d run along the outer periphery of a pot-shaped tip end part 6c, covering the shield gas jetted from the guide hole 6a to form a gas curtain, and that shields before the gas blow-off port 5d the spatters which is generated in welding and running to the gas blow-off port 5d. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an arc welding torch used for continuously supplying a welding wire for arc welding.

  In arc welding, a welding wire protruded from the tip of the torch is brought close to the work piece, and an antioxidant gas for welding (hereinafter referred to as shield gas) made of carbon dioxide, argon gas, helium gas, etc. is blown out from the tip of the torch. Cover the periphery of the arc generated between the welded material and the welding wire with shielding gas, and prevent the atmospheric air from flowing into the welded part, while melting the work piece and the welding wire by the arc, Formed and welded.

  For example, in the arc welding torch described in Japanese Patent Application Laid-Open No. 2002-224837, a central hole that penetrates the shaft portion and through which a welding wire for consumable electrode arc welding is inserted is formed through the central hole. A conductive, rod-shaped torch tip member that guides the shielding gas to the tip portion, and a rear end portion that is conductively and rotatably supported on the tip side of the torch tip member, and the tip portion extends from the central hole An arc welding torch comprising a conductive tip biased in a direction in contact with the derived welding wire and a cylindrical nozzle covering the outside of the tip, and covering the tip inside the nozzle As described above, a through hole through which the welding wire is inserted is formed at the tip, and a cap formed of a curved surface having a high thermal conductivity and a smooth outer surface is provided at the tip of the torch tip member.

This arc welding torch blows shield gas from the gap between the insertion hole at the cap tip and the welding wire, blows it from the nozzle, and blows it to the welding wire at the tip of the cap. A gas curtain is formed so as to wrap the gas, and the arc generated from the welding wire is covered with the shielding gas and the surrounding gas curtain.
JP 2002-224837 A

  In the arc welding torch described in Patent Document 1, the entire nozzle is formed of a cylinder having the same diameter, and a shield gas is blown out from the nozzle outlet to form a gas curtain. Since this arc welding torch has a wide gas shield range, a large amount of shield gas is consumed. In addition, if a part of the spatter that is generated by welding during the welding is fused in the cap of the torch tip or the nozzle cylinder and the outlet is clogged, the amount of shielding gas blown out is limited and the shielding effect is reduced. Therefore, there is a problem that it is necessary to remove the spatter fused during welding.

  The present invention solves the above-described problem. Even if the diameter of the nozzle outlet is small, the gas curtain can be created by the shield gas injected from the nozzle, and it is scattered during welding and rushed to the tip of the nozzle. An object of the present invention is to provide an arc welding torch that shields the spatter coming before the nozzle outlet, prevents spatter from adhering to the nozzle outlet, and reliably prevents oxidation near the weld. .

In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a tip that passes through a welding wire through a welding wire and is energized is coaxially attached to the tip, and shield gas is passed through an internal gas flow path to A torch body that flows out from the gas discharge port, and a gas supply port that has one end attached to the torch body and encloses the gas discharge port and the chip, and a shield gas that flows into the inside from the gas discharge port is provided at the other end A nozzle body that flows out from the outside, and one end of which is attached to the nozzle body, covers a gas supply port of the nozzle body, and an annular gas outlet is formed between the nozzle body and the other end. A nozzle cover for injecting shield gas flowing into the inside from the supply port to the outside from the gas outlet, and a crucible tip end projecting from the gas outlet at the tip of the nozzle body. A guide hole that passes through the welding wire and injects the shield gas to the outside, and the shield gas injected from the gas outlet is arranged at the outer periphery of the crucible tip. A spatter guard that shields spatter generated in welding and rushing to the gas outlet before the gas outlet, while covering the shield gas injected from the guide hole while being along the surface ,
An arc welding torch characterized by comprising:

  According to a second aspect of the present invention, the sputter guard is attached to the tip of the nozzle body with a crucible tip having a diameter larger than the outer diameter of the tip protruding between the nozzle cover and the nozzle body. The arc welding torch according to claim 1, wherein the shield gas injected from the formed annular gas outlet is expanded along the outer peripheral surface to increase the inner diameter to form a cylindrical gas curtain.

  According to the present invention, the diameter of the nozzle outlet is reduced so that a shield gas having a sufficient gas pressure is injected from the nozzle at a relatively low gas pressure, and the cylinder diameter of the gas curtain formed by the shield gas is reduced. By forming, a gas curtain is injected with a sufficient gas pressure with a small amount of shielding gas, so that the vicinity of the welded portion can be reliably prevented from being oxidized.

  In addition, by providing a spatter guard that protrudes from the nozzle outlet, spatter that scatters and rushes to the nozzle tip due to an arc flying between the welding wire and the work piece during manual welding. The spatter guard is shielded in front of the nozzle outlet so that it does not adhere to the nozzle outlet, so that the nozzle outlet is not clogged and the amount of shield gas injection is not limited. During the work, it is possible to avoid a situation where the welding work such as the replacement of the nozzle or the removal of the spatter in the spatter guard is interrupted, and an efficient welding work can be performed.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments.

  1 is a cross-sectional view showing a first embodiment of the present invention, FIG. 2 is a partially enlarged cross-sectional view for explaining the operation, FIG. 3 (a) is an exploded perspective view, and FIG. 3 (b) is a right half in cross section. FIG.

  1 to 3, an arc welding torch 1 includes a torch body 2, a conductive tip 3 that is coaxially attached to the tip of the torch body 2, one end attached to the torch body 2, and the vicinity of the tip and From the nozzle body 4 containing the chip 3, a nozzle cover 5 having one end attached to the nozzle body 4, and a metal (or ceramics) sputter guard 6 attached to the tip of the nozzle body 4. It is configured.

  The torch main body 2 allows the shield gas to flow out from a plurality of gas discharge ports 2b provided at equal angles around the axis in the vicinity of the tip through the internal gas flow path 2a. Further, the tip 3 that is coaxially mounted on the tip of the torch body 2 passes through the welding wire 7 through the shaft hole 3 a and is energized and is guided to the tip side of the torch body 2.

  The nozzle body 4 is attached to the torch body 2 by a female screw 4 s at one end, includes the gas discharge port 2 b and the tip 3, and a space portion 4 a is formed between the tip 3 and the nozzle body 4. The nozzle body 4 is formed with a male screw 4b having a diameter slightly smaller than that of the outer periphery of the nozzle body 4 in the vicinity of the other end, and at the tip of the male screw 4b is a cylindrical portion 4c having a diameter smaller than the outer diameter of the male screw 4b. Is provided. A plurality of gas supply ports 4d are provided at equal angles around the base axis of the cylindrical portion 4c, and a female screw 4e is formed inside the distal end of the cylindrical portion 4c.

  The space 4 a between the tip 3 and the nozzle body 4 has an upper portion communicating with the gas flow path 2 a via the gas discharge port 2 b and a lower portion communicating with a plurality of gas supply ports 4 d provided near the tip of the nozzle body 4. is doing. Therefore, a part of the shield gas supplied from the gas discharge port 2b passes through the shaft hole 3a of the chip 3, and the remaining shield gas is branched and ejected from each gas supply port 4d.

  The nozzle cover 5 has an outer periphery that is the same diameter as the nozzle body 4 at the mounting portion 5a at one end, and is attached to the nozzle body 4 by screwing a female screw 5b formed inside the male screw 4b. The nozzle cover 5 covers the outer periphery in the vicinity of the tip of the nozzle body 4 and forms a coaxial double cylinder having the nozzle body 4 as an inner cylinder. The space portion 5c formed between the nozzle cover 5 and the vicinity of the tip of the nozzle body 4 has an upper portion communicating with each gas supply port 4d, and a lower tip connected to an annular gas outlet 5d constituting a nozzle outlet. Communicate. Therefore, the shield gas supplied from each gas supply port 4d is injected from the gas outlet 5d.

  The sputter guard 6 has a guide hole 6a for injecting the shielding gas supplied from the gas flow path 2a to the outside, and the male screw 6b formed on the upper part is a female screw in the small diameter cylindrical portion 4c at the tip of the nozzle body 4. 4e is screwed and the crucible-shaped tip 6c protrudes from the gas outlet 5d at the tip of the nozzle body 4 and is fixed. The pot-shaped tip portion 6 c is formed to have a larger diameter than the outer periphery of the small-diameter cylindrical portion 4 c of the nozzle body 4. The guide hole 6a has a funnel shape that tapers into a conical shape from the upper end and has a tip formed in a hole 6d having a predetermined length. The guide hole 6a is guided through the welding wire 7 to the outside. The vase-shaped tip 6c is generally spherical and the outer surface is spherical.

  Next, the operation during welding of the arc welding torch 1 will be described. The arc welding torch 1 blows an arc between the workpiece 8 and the welding wire 7, and forms and welds a weld bead 9 with this heat. During welding, the tip of the welding wire 7 protruding from the spatter guard 6 can be visually observed from the outside. Therefore, it is possible to perform welding while confirming the true core portion of the welded portion, and core blurring can be prevented.

  Further, spatter is generated during welding and scatters violently, and a part of the spout rushes toward the gas outlet 5d at the tip of the nozzle body 4. In this case, since the pot-shaped tip portion 6c of the sputter guard 6 protrudes from the gas outlet 5d, the sputter guard 6 is shielded by the sputter guard 6 before the gas outlet 5d. It does not adhere to 5d. Further, some spatters collide with the tip 6c of the sputter guard 6, but the surface is spherical so that it is difficult to adhere, and even if it is primarily attached, it is peeled off by the spattering that collides later. Spatter does not adhere to 6c.

  At the time of welding, the spatter guard 6 injects a shielding gas from the gap between the guide hole 6a and the welding wire 7 to cool the welded portion. When the shield gas passes through the space 5c between the double cylinders of the nozzle body 4 and the nozzle cover 5, the gas outlet 5d is formed in a narrow annular shape, so that the gas pressure is increased, and the gas outlet 5d. The shield gas having a sufficient gas pressure is injected in a cylindrical shape.

  The sputter guard 6 acts to maintain the cylindrical shape without blocking the shield gas cylinder along the outer peripheral surface of the crucible tip 6c with the shield gas injected from the gas outlet 5d. To do. Therefore, the shield gas injected from the gas outlet 5d concentrates in a cylindrical shape on the welded portion, covers the shield gas injected from the guide hole 6a, and forms a cylindrical gas curtain.

  As described above, the arc welding torch according to the present invention injects the shielding gas from the double cylinder gas outlet 5d formed by the nozzle body 4 and the nozzle cover 5, and the sputter guard 6 injects the cylinder from the gas outlet 5d. A cylindrical gas curtain can be formed by covering the shield gas sprayed from the guide hole 6a along the outer peripheral surface of the shield gas, so that a small amount of shield gas can reliably prevent oxidation near the weld. it can.

  Further, since the arc welding torch of the present invention is provided with the spatter guard 6 so as to protrude from the gas outlet 5d, even if spatter scattered at the tip of the nozzle body 4 rushes to the gas outlet 5d. Since it was shielded by the spatter guard 6 before 5d and prevented from adhering to the gas outlet 5d, the gas outlet 5d is not clogged by sputtering and the amount of shield gas injection is not limited, and welding work is being performed. In addition, it is possible to avoid a situation where the welding work such as replacement of the nozzle or removal of the spatter in the spatter guard is interrupted, and an efficient welding work can be performed.

It is sectional drawing which shows Example 1 of this invention. FIG. 2 is a partially enlarged cross-sectional view for explaining the operation of the first embodiment. 1A is an exploded perspective view of FIG. 1, and FIG. 1B is an exploded front view of the right half of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Arc welding torch 2 Torch main body 2a Gas flow path 2b Gas discharge port 3 Tip 3a Shaft hole 4 Nozzle main body 4a, 5c Space part 4b, 6b Male screw 4c Small diameter cylindrical part 4d Gas supply port 4e, 5b Female screw 5 Nozzle Cover 5a Mounting portion 5d Gas outlet 6 Spatter guard 6a Guide hole 6c Vase-shaped tip 6d Pore 7 Welding wire 8 Workpiece 9 Weld bead

Claims (2)

A torch body that has a tip that is energized through the welding wire through the shaft hole and is coaxially attached to the tip, allows the shield gas to pass through the internal gas flow path and outflow from the gas outlet at the tip,
A nozzle main body having one end attached to the torch body and enclosing the gas discharge port and the chip, and a shield gas flowing into the inside from the gas discharge port and flowing out from a gas supply port provided at the other end;
One end is attached to the nozzle body, covers the gas supply port of the nozzle body, and an annular gas outlet is formed between the other end and the nozzle body, and flows into the interior from the gas supply port A nozzle cover for injecting the gas from the gas outlet to the outside,
A crucible tip is projected from the gas outlet at the tip of the nozzle body and is coaxially mounted on the nozzle body, and has a guide hole that penetrates the welding wire and passes the inside to inject shield gas to the outside. A gas curtain is formed to cover the shield gas injected from the guide hole while keeping the shield gas injected from the gas outlet along the outer peripheral surface of the crucible tip, and the gas generated during welding A sputter guard that shields the spatter that rushes to the air outlet in front of the gas outlet;
Arc welding torch characterized by comprising   The sputter guard is attached to the tip of the nozzle body with a crucible-shaped tip protruding larger than the outer diameter of the tip, and is injected from an annular gas outlet formed between the nozzle cover and the nozzle body. The arc welding torch according to claim 1, wherein the shield gas to be formed is formed in a cylindrical gas curtain by extending the inner diameter along the outer peripheral surface.

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