JP4685080B2 - Arc welding torch - Google Patents

Description

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

  In arc welding, a tip is coaxially attached to the tip of the torch body, a welding wire that is inserted through the tip hole of the tip and protrudes from the tip of the torch approaches the work piece, and carbon dioxide gas, argon gas, helium gas, etc. An anti-oxidation gas for welding (hereinafter referred to as “shield gas”) is blown from the tip of the torch, the arc generated between the work piece and the welding wire is covered with the shield gas, and air in the atmosphere flows into the weld. The welding object and the welding wire are melted by arc to form a weld bead and welded.

For example, in a welding torch for gas-encapsulated arc welding described in Japanese Patent Application Laid-Open No. 2007-54872, a small-diameter passage having a small diameter and a shield gas ejection hole is provided in a hollow region where a torch body and a tip are joined and formed in communication. As a result, the flow of the shield gas is restricted when it passes through the small-diameter passage having a small diameter. Thereby, the ejection flow rate of the shield gas can be reduced.
JP 2007-54872 A

  In this type of arc welding torch, a tip for inserting a welding wire into a shaft hole is attached to the tip of the torch body at the root portion, and a welding nozzle is attached to the torch body so as to contain the tip. A space as a shield gas flow path is provided between the chips, and the tip of the chip protrudes from the torch body to become a free end. Further, since the welding wire inserted through the shaft hole of the tip is melted and consumed by the arc, it is wound around a reel (not shown) and supplied in a fixed amount from the reel. For this reason, there is a problem that the tip end portion of the tip fluctuates due to the bending flaw of the welding wire, the tip of the welding wire comes off the target position during welding, and the bead meanders.

  SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and in an arc welding torch in which a tip for inserting a welding wire into a shaft hole protrudes from the torch main body and is arranged at a free end, it is wound around a reel and has a bending wrinkle. Even if the welding wire is supplied from a reel and biased by the bending of the welding wire, the center position of the tip shaft hole is stable, and the arc welding torch maintains a stable state without wobbling the tip of the welding wire Is to provide.

  The present invention also provides an arc welding torch that shields the spatter scattered during the welding and rushing to the tip of the nozzle cover in front of the air outlet of the nozzle cover.

  The present invention also provides an arc welding torch in which shield gas is jetted to the outside at a uniform pressure from a gas outlet at the tip of a nozzle cover.

  In order to solve the above-mentioned problem, the invention according to claim 1 has a first shaft hole through which the shield gas and the welding wire pass and communicates with the first shaft hole around an axis in the vicinity of the tip so that the shield gas flows out. A torch body having a gas discharge port provided with a plurality of horizontal holes, a shield gas supplied from the torch body and a welding wire passing through the end of the torch body coaxially mounted on the tip of the torch body, and the tip passing through the tip A gas discharge port having a second shaft hole formed in the chip receiving port for mounting and provided with a plurality of horizontal holes that communicate with the second shaft hole and flow out of the shield gas around a central shaft. A sub-torch having an end that is insulated and attached to the outer periphery of the torch main body, encloses the torch main body and the sub-torch, and the shield gas supplied from the gas discharge port flows out from the tip opening A nozzle body, a third shaft hole through which the welding wire is inserted, a tip attached to the tip receiving port of the sub torch, a center hole into which the sub torch is fitted, and an axial ventilation hole Is provided around the center hole, and is disposed between the tip of the nozzle body and the gas discharge port of the sub-torch. The shield gas supplied from the nozzle body is caused to flow out of the vent hole, and A ring whose position is guided so that the shield gas flowing out from the pores is located in a gap between the shield gases flowing out from the side holes by the action of the shield gas flowing out from the side holes of the gas discharge port; A wire guide that is attached to the tip of a sub torch and encloses the tip, the welding wire is inserted into a hole in the tip, a terminal is attached to the nozzle body, and the ring is The nozzle main body includes a sub-torch that is loosely fitted into the nozzle body, and the wire guide is coaxially projected from the tip opening by a predetermined length to form an annular gas outlet between the tip opening and the wire guide. A nozzle cover that injects the shield gas supplied from the outside along the outer periphery of the wire guide, and the ring has a shield gas that flows out from each of the vent holes out of each side hole of the gas discharge port. The position is guided so as to be in the gap between the shield gases to be urged so that the sub torch inserted into the center hole is maintained at the center position of the nozzle cover. It is a torch.

  According to a second aspect of the present invention, the ring has a shape in which each corner of the polygonal cylinder is a curved surface that matches the inner surface of the nozzle cover cylinder, and is loosely fitted in the cylinder of the nozzle cover. The arc welding according to claim 1, wherein a gap portion capable of venting in an axial direction is formed between an inner surface of a tube of the nozzle cover and an outer peripheral surface of the ring, and an axial vent is provided in each corner portion. It is a torch.

  According to a third aspect of the present invention, the ring has a cylindrical shape, and the number of axial ventilation holes around the center hole is equal to or equal to the number of lateral holes of the gas discharge port. An arc welding torch according to claim 1.

  According to a fourth aspect of the present invention, the nozzle cover and the wire guide are made of ceramics, and the nozzle cover and the wire guide are attached to the end of the sub torch, and the position where the end of the sub torch is attached to the tip of the torch body is set. The arc welding torch according to any one of claims 1 to 3, further comprising means for setting a length of a wire guide protruding from the gas outlet of the nozzle cover.

  According to a fifth aspect of the present invention, the nozzle cover has an empty portion for collecting shield gas supplied from the other end opening of the nozzle body between the ring and the gas outlet, The arc welding torch according to any one of claims 1 to 4, wherein the arc welding torch is stored in the empty portion and injected from the gas outlet on the other end side with an increased pressure.

  The arc welding torch according to the present invention stabilizes the center position of the tip shaft hole and does not fluctuate the tip of the welding wire even if it is biased by the bending wire from the welding wire inserted through the tip shaft hole. The state is maintained.

  In the arc welding torch according to the present invention, the nozzle cover and the wire guide are made of ceramics, and the wire guide shields the spatter scattered during the welding and rushing to the tip of the nozzle cover before the nozzle cover outlet. Like to do. Therefore, spatter does not adhere to the air outlet of the nozzle cover, and reliable oxidation prevention in the vicinity of the welded portion can be achieved. Also, ceramic nozzle covers and wire guides are made of ceramics with a spherical surface, so they are difficult to adhere, and even if they are primarily attached, they are peeled off by sputtering that collides later. Spatter does not adhere to the tip.

  Further, the arc welding torch according to the present invention is provided with an empty portion for storing the shield gas in the nozzle cover, and the shield gas supplied from the nozzle body is stored in the empty portion to increase the pressure from the gas outlet at the tip. It is made to inject.

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

  1 is a longitudinal sectional view showing a first embodiment of the present invention, FIGS. 2A and 2B are partially enlarged transverse sectional views for explaining the operation of the ring, and FIG. 3A is an exploded perspective view. FIG. 3B is an exploded front view with the left half sectioned.

  1 to 3, an arc welding torch 1 includes a torch body 2, a sub-torch 3 that is coaxially attached to the tip of the torch body 2, a flange cylinder 4 that is insulated and attached to the outer periphery of the torch body 2, A nozzle body 5 having an end attached to the flange cylinder 4 and including the vicinity of the tip of the torch body 2 and the sub-torch 3, a tip 6 attached to the tip of the sub-torch 3, and the sub-torch 3 is fitted into the nozzle body 5. A ring guide 7, a wire guide 8 that is attached to the tip of the sub torch 3 and encloses the tip 6, and a nozzle cover 9 that has one end attached to the tip of the nozzle body 5.

  The torch body 2 has a first shaft hole 21 through which shield gas passes, and communicates with the first shaft hole 21 at an equal angle around an axis in the vicinity of the tip so that the shield gas flows out. .. Have a gas discharge port 23 provided with. The welding wire W is supplied through the first shaft hole 21. A female screw 2 a is formed at the tip of the torch body 2.

  The sub torch 3 is made of brass and has male screws 3a and 3b formed at both ends, and a second shaft hole 31 is provided through the center. The sub torch 3 is screwed to the female screw 2 a at the tip of the torch body 2 in a state where the nut 10 is screwed to the male screw 3 b at the end, and is fixed to the tip of the torch body 2. In the sub torch 3, the second shaft hole 31 communicates with the first shaft hole 21 and the welding wire W supplied from the first shaft hole 21 passes through the second shaft hole 31. In this case, the length at which the tip of the sub torch 3 protrudes from the tip of the torch body 2 is set at a position where the nut 10 is screwed into the male screw 3 b at the end of the sub torch 3. Further, the inside of the hole in the vicinity of the tip of the second shaft hole 31 is formed with a diameter larger than that of the other part, and serves as a chip receiving port 30 into which the chip 6 can be mounted. Further, the sub torch 3 has a gas discharge port 33 in which a plurality of lateral holes 32 communicating with the second shaft hole 31 are provided at equiangular intervals around an axis near the center.

  The flange cylinder 4 is made of metal and is fixed to the outer periphery of the torch body 2 via an insulating member 41, and a male screw 4a is formed at the tip.

  The nozzle body 5 is made of aluminum and has a female screw 5b formed at the end thereof screwed into a male screw 4a at the tip of the flange cylinder 4 and is insulated and attached to the outer periphery of the torch main body 2 via the flange cylinder 4. The shield gas supplied from the gas discharge port 23 is caused to flow out from the other end opening 51. A male screw 5 a is formed at the tip of the nozzle body 5.

  The tip 6 is made of chrome copper and has a third shaft hole 61 extending through the center thereof. The welding wire W is inserted into the third shaft hole 61 and attached to the tip receiving port 30 of the sub torch 3.

  The ring 7 is made of a ceramic and is a polygonal cylindrical shape (a square cylinder in FIG. 2A) shown in FIG. 2A and a cylindrical ring 7b shown in FIG. 2B. In any case of the rings 7a and 7b, a center hole 71 having a circular cross section is provided, and a plurality of axial ventilation holes 72, 72,... The sub torch 3 is inserted into the. The ring 7 is loosely fitted to the nozzle cover 9 and is arranged at the tip of the nozzle body 5, so that the number of the axial air holes 72 differs depending on the shape. This will be described later.

  The wire guide 8 is made of ceramic and has a cylindrical shape having a bottom 8a. A female screw 8b is formed in the cylinder, and a hole 81 is provided in the center of the bottom 8a at the tip in the axial direction. The wire guide 8 is attached to the sub torch 3 by inserting the welding wire W through the hole 81 at the tip, screwing the female screw 8b with the male screw 3a at the tip of the sub torch 3, and enclosing and supporting the tip of the tip 6. .

  The nozzle cover 9 has a cylindrical shape made of ceramics, has a female screw 9b formed at the end, and an opening 92 provided at the tip. Then, with the ring 7 loosely fitted in the cylinder 91 in the vicinity of the end, the end female screw 9 b is screwed into the male screw 5 a provided at the tip of the nozzle body 5 and attached to the nozzle body 5. Accordingly, the nozzle cover 9 includes the sub torch 3 by causing the wire guide 8 attached to the tip of the sub torch 3 to protrude from the opening 92. Therefore, the opening 92 becomes an annular air outlet 92a in which the wire guide 8 is disposed at the center.

  Further, the ring 7 is installed at the tip of the nozzle body 2 and directly above the gas discharge port 33 of the sub-torch 3, and the shield gas supplied from the nozzle body is disposed below the plurality of vent holes 72, 72,. Although it flows out, the shield gas flowing out from the horizontal holes 32 and 32 of the gas discharge port 33 of the sub torch 3 acts to prevent the flow of the shield gas flowing out from the vent hole 72. Therefore, the ring 7 guides the position so that the shield gas flowing out from the vent hole 72 passes through the gap between the shield gases, avoiding the shield gas flowing out from the lateral holes 32, 32 of the gas discharge port 33. Is done. Since the number of gaps between the shield gases is the same as the number of the horizontal holes 32, 32,... Of the gas discharge port 33, the number of the vent holes 72 is equal to the number of horizontal holes of the gas discharge port. Alternatively, when a multiple thereof is provided, in the ring 7, the shield gas flowing out from the vent hole 72 and the shield gas flowing out from the horizontal holes 32, 32 of the gas discharge port 33 are converted into the horizontal holes 32, 32 of the gas discharge port 33. The sub torch 3 fitted in the center hole 71 is biased so as to be maintained at the center position of the nozzle cover 9 by the action of the position being guided so as to pass through the gap between the shield gases flowing out from the nozzle.

  When a ring 7a having a polygonal cylinder shape (a square cylinder in FIG. 2A) is applied as the ring 7, when loosely fitted in the cylinder of the nozzle cover 9, the inner surface of the cylinder of the nozzle cover 9 and the ring 7a Clear portions 73, 73,... That can be ventilated in the axial direction are formed between the outer peripheral surface 7b and the outer peripheral surface 7b. These gap portions 73, 73,... Are positions between the corner portions, and an intermediate position 73a of the gap portion 73 shown by X in the figure is an intermediate position between the corner portions. When the air holes 72, 72,... Are provided at the respective corners of the ring 7a, the axial air holes 72, 72,... Including the number of the transparent portions 73 are provided around the center hole of the ring 7a. The angle is equal to the number of the horizontal holes of the gas discharge port.

  When the cylindrical ring 7b is used as the ring 7, the number of the axial vent holes 72, 72,... Around the center hole of the ring 7a is equal to the number of the lateral holes of the gas discharge port. Alternatively, a multiple thereof may be provided.

  An empty portion 93 is provided at the lower portion of the ring 7, and the shield gas that has passed through the ring 7 and the shield gas that flows out from the gas discharge port 33 of the sub-torch 3 are collected and blown out from a narrow annular outlet 92 a. Then, the shielding gas is blown out in a cylindrical shape with a substantially uniform pressure with the gas pressure being increased.

  Next, the operation during welding of the arc welding torch 1 will be described. At the time of welding, a welding wire W is supplied to the torch body 2 from a reel (not shown), the welding wire W projected from the wire guide 8 at the tip of the torch is brought close to the workpiece 100, and an arc is blown out while blowing shield gas from the blowout port 92a. As a result, the workpiece 100 and the welding wire W are melted to form a weld bead 101 and welded.

  At the time of welding, the tip 6 receives bending wrinkles from the welding wire W, but the shield gas supplied from the nozzle body 5 flows out from the plurality of vent holes 72, 72,. Then, the position of the ring 7 is guided so as to pass through the gap between the shield gases while avoiding the shield gas flowing out from the gas discharge port 33 of the sub torch 3. The ring 7 urges the sub torch 3 fitted in the center hole 71 to be maintained at the center position of the nozzle cover 9 by the action of inducing the position described above. As a result, even if the tip 6 is biased by the bending wire W from the welding wire W, the sub torch 3 is biased so as to maintain the center position of the nozzle cover 9, so that the position of the tip 6 is stabilized, and the welding wire The tip of no longer fluctuates.

  Further, the wire guard 6 cools the welded portion by injecting a shielding gas from a gap between the hole 81 at the tip and the welding wire W. At this time, the shield gas is stored in the hollow portion 93 provided in the lower portion of the ring 7 loosely fitted in the cylinder of the nozzle cover 9 and blown out from the narrow annular outlet 92a, so that the gas pressure is increased and the annular blowing is performed. A shield gas having a sufficient gas pressure is blown out in a cylindrical shape from the outlet 92a at a substantially uniform pressure. Therefore, the shield gas injected from the air outlet 92a is concentrated in a cylindrical shape at the welded portion and covers the shield gas injected from the hole 81 at the tip of the wire guard 6 to form a cylindrical gas curtain.

  In this case, the position of the nut 10 to be screwed into the male screw 3b at the end of the sub torch 3 is adjusted in advance, and the protruding length of the wire guide 8 attached to the tip of the sub torch 3 from the tip of the torch main body 2 is set during welding. The spatter that scatters and rushes to the tip of the nozzle cover 9 may be set at a position where the wire guide 8 can be shielded before the air outlet 92. By doing so, spatter does not adhere to the air outlet 92 of the nozzle cover 9, and reliable oxidation prevention in the vicinity of the welded portion can be achieved.

  Since the nozzle cover 9 and the wire guide 8 are made of ceramics and have a spherical surface, the nozzle cover 9 and the wire guide 8 are difficult to adhere to the spatter. The spatter does not adhere to the tip of the wire guide 8.

It is a longitudinal cross-sectional view which shows Example 1 of this invention. (A), (b) is a partial expanded cross-sectional view for demonstrating the effect | action of a ring. 1A is an exploded perspective view of FIG. 1, and FIG. 1B is an exploded front view of the left half of FIG.

Explanation of symbols

1 Arc welding torch 2 Torch body 2a, 4a, 5b, 8b Female thread 3a, 3b, 5a, 9b Male thread 3 Sub torch 4 Flange cylinder 5 Nozzle body 6 Tip 7, 7a, 7b Ring 8 Wire guide 9 Nozzle cover 10 Nut 21 First 1 shaft hole 22, 32 Horizontal hole 23 Gas discharge port 30 Chip receiving port 31 2nd shaft hole 33 Gas discharge port 41 Insulating member 51 Opening 61 3rd shaft hole 71 Center hole 72 Vent hole 73 Clearance part 81 Insertion hole 91 In-cylinder 92 Opening 92a Air outlet 93 Empty part 100 Workpiece 101 Weld bead W Welding wire

Claims (5)

A torch body having a first shaft hole through which a shield gas and a welding wire pass and a gas discharge port provided with a plurality of lateral holes through which the shield gas flows out around the shaft near the tip When,
A second shaft hole is formed in a tip receiving hole through which the distal end is coaxially attached to the tip of the torch body and the shield gas supplied from the torch body and the welding wire pass and the tip is attached to the tip. A sub-torch having a gas discharge port provided with a plurality of lateral holes through which a shielding gas flows out in communication with the second shaft hole around a central axis;
A nozzle body that is insulated and attached to the outer periphery of the torch body, encloses the torch body and the sub-torch, and causes a shield gas supplied from the gas discharge port to flow out from the tip opening;
A tip having a third shaft hole through which the welding wire is inserted and attached to the tip receiving opening of the sub torch;
The nozzle body has a center hole into which the sub torch is inserted, and a plurality of axial ventilation holes are provided around the center hole, and is disposed between a tip of the nozzle body and a gas discharge port of the sub torch. Shield gas supplied from the vent hole is caused to flow out from the vent hole, and the shield gas flowing out from the vent hole is caused to flow out from the horizontal hole by the action of the shield gas flowing out from the horizontal hole of the gas discharge port. A ring guided in the gap between the gases;
A wire guide that is attached to the tip of the sub-torch, encloses the tip, and the welding wire is inserted through a hole in the tip;
A distal end is attached to the nozzle body, the ring is loosely fitted in a cylinder to enclose the sub torch, and the wire guide is protruded coaxially from the tip opening by a predetermined length so as to be between the tip opening and the wire guide. An annular gas outlet, and a nozzle cover for injecting the shield gas supplied from the nozzle body to the outside along the outer periphery of the wire guide,
The ring is inserted into the center hole by being guided in a position so that the shield gas flowing out from each of the vent holes comes to a gap between the shield gases flowing out from the side holes of the gas discharge port. An arc welding torch characterized in that the sub torch is biased so as to be maintained at the center position of the nozzle cover.   The ring has a shape in which each corner portion of the polygonal cylinder is curved to match the inner surface of the nozzle cover cylinder, and is loosely fitted in the nozzle cover cylinder so that the inner surface of the nozzle cover cylinder and the ring The arc welding torch according to claim 1, wherein a transparent gap portion capable of venting in the axial direction is formed between the outer peripheral surface and an axial vent hole is provided at each corner portion.   2. The arc welding torch according to claim 1, wherein the ring has a cylindrical shape, and the number of axial ventilation holes around the central hole is equal to or a multiple of the number of lateral holes of the gas discharge port. The nozzle cover and the wire guide are made of ceramics,
Means for setting a length at which the wire guide protrudes from the gas outlet of the nozzle cover by setting the position where the end of the sub torch is attached to the end of the sub torch and the end of the sub torch is attached to the tip of the torch body; The arc welding torch according to any one of claims 1 to 3.   The nozzle cover has an empty portion for storing a shield gas supplied from the other end opening of the nozzle body between the ring and the gas outlet, and the shield gas is stored in the empty portion to be disposed on the other end side. The arc welding torch according to any one of claims 1 to 4, wherein the pressure is increased from the gas outlet and injected.

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