JPH0819868A - Gas shielded metal-arc welding machine - Google Patents

Abstract

PURPOSE:To enable an operator to set a timing of jetting air to remove spatter corresponding to the condition in a gas shielded metal-arc welding machine. CONSTITUTION:This gas shielded metal-arc welding machine is an arc welding machine to execute arc welding in a shield gas atmosphere with a welding wire fed continuously, and it is provided with a torch, a shield gas supplying part, a gas supplying part and a controller 14. The torch has a supporting part which extends in one direction in order to support the welding wire, and a nozzle body arranged on the circumference of the supporting part in an interval. The shield gas supplying part supplies the shield gas between the supporting part and the nozzle part. The gas supplying part supplies the gas for removing spatter between the supporting part and the nozzle body. The controller 14 can be made to change a supplying timing of the gas supplying part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torch for a welding machine, and more particularly to a torch used in a gas shielded arc welding machine for performing arc welding in a shielding gas atmosphere by a continuously supplied filler metal.

[0002]

2. Description of the Related Art A torch used in a gas shielded arc welder for performing arc welding in a shield gas atmosphere such as an inert gas or carbon dioxide gas mainly extends in one direction to support a welding wire as a filler metal. And a cylindrical nozzle arranged so as to form an annular space around the supporting portion. The filler support is fixed to the tip of the coil liner, and has a support hole therein for supporting the welding wire supplied from the coil liner. A hole larger than the diameter of the welding wire is formed in the coil liner. Further, the filler material supporting portion has a hole that connects the hole of the coil liner to the annular space between the supporting portion and the nozzle.

Shielding gas or high-pressure air for removing spatter is supplied from the hole of the coil liner and is jetted from the tip of the torch through the annular space. Shielding gas is injected during welding to wrap the molten metal and prevent its oxidation and nitriding. The high-pressure air is jetted after the welding is completed, and blows off the spatter adhered to each member when passing through the annular space. As a result, it is possible to prevent a decrease in the amount of shield gas jetted due to the adhesion of spatter.

[0004]

In a gas-shield arc welding torch, it is possible that the effect of removing spatter changes depending on the timing at which high-pressure air for removing spatter is jetted. Examples of different timings are given below. Air is injected immediately after the completion of welding, or when the cooling of spatter progresses after a lapse of a certain time after the completion of welding. Further, air is jetted every welding one time, or air is jetted after welding is performed a plurality of times and spatter is accumulated to some extent.

In the conventional gas shielded arc welding torch, the timing for injecting the high pressure air for removing spatter is fixed. Therefore, the operator cannot set the optimum timing according to the conditions. An object of the present invention is to allow an operator to set the timing of injecting air for removing spatters according to conditions in a gas shielded arc welder.

[0006]

A gas shielded arc welder according to the present invention is an arc welder for performing arc welding in a shield gas atmosphere by a continuously supplied wire-shaped filler material, which comprises a torch and a torch. A shield gas supply unit, a gas supply unit, and a timing changing unit are provided. Torch
It has a filler material support portion that extends in one direction to support the filler material, and a cylindrical nozzle portion that is arranged around the filler material support portion at a distance. The shield gas supply unit supplies the shield gas between the filler material support unit and the nozzle unit. The gas supply unit supplies a gas for removing spatter between the filler material support unit and the nozzle unit. The timing changing means can change the supply timing of the gas supply unit.

The timing changing means is an input means for the operator to input the timing, a storage means for storing the timing input by the input means, and a control for supplying gas to the gas supply section at the timing stored by the storage means. And means.

[0008]

In the gas shielded arc welding machine according to the present invention,
During welding, the filler metal supported by the filler support is continuously supplied, and at the same time, the shield gas supply unit supplies the shield gas between the filler support and the nozzle. It As a result, the arc and molten metal in the welded portion are wrapped in the inert gas and welded. During this welding,
Molten metal spatters and scatters at the tip of the nozzle. The slaughter adheres to the filler material supporting portion and the cylindrical nozzle portion. After the welding is completed, gas is supplied from the gas supply section between the filler material support section and the nozzle section to blow off the spatter. The timing for supplying the spatter removing gas is changed by the timing changing means. Therefore, spatter can be sufficiently removed even if the conditions change.

If the timing changing means includes input means, storage means and control means, the change is ready,
Simpler configuration.

[0010]

EXAMPLES In the first embodiment FIG. 1, inert gas shielded arc welding machine 1 in which one embodiment of the present invention is employed mainly from the welding power source 2 and the gas supply device 3 and the wire feeder 4 and the torch 5 which It is configured.

The welding power source 2 is for generating a DC welding current from a three-phase 200-volt AC power source. The welding power source 2 includes a control unit 14 (described later). A ground electrode 16 is connected to the welding power source 2. The gas supply device 3 includes an argon gas cylinder 6 filled with high-pressure argon gas, a carbon dioxide gas cylinder 7 filled with high-pressure carbon dioxide gas, and a mixing chamber 8 for mixing argon gas and carbon dioxide gas to form a shield gas. It has and. An argon gas flow rate controller 9 is arranged between the argon gas cylinder 6 and the mixing chamber 8. Further, a carbon dioxide gas flow rate adjuster 10 is arranged between the carbon dioxide gas cylinder 7 and the mixing chamber 8. A mixing prevention circuit 35 is connected to the mixing chamber 8 via a pipe and a rubber hose. To the mixing prevention circuit 35, for example, an air source (not shown) including a high-pressure compressor that generates compressed air of 1 MPa is also connected. The mixing prevention circuit 35 is provided to control the air supplied from the air source and the shield gas supplied from the gas supply device 3 and prevent the air from mixing with the shield gas. The mixing prevention circuit 35 has a rubber hose 17
It is connected to the torch 5 via.

The wire supply device 4 includes a wire reel mounting portion 12 for mounting the wire reel 11 on which the welding wire 26 is wound, and a feed roller for supplying the welding wire 26 wound on the wire reel 11 into the torch 5. 13 and 13. The feed roller 13 supplies the welding wire 26 to the torch 5 at a constant speed with respect to the welding speed.

The torch 5 is provided with a coil liner 20 for inserting the welding wire 26 and a torch nozzle 21 attached to the tip of the coil liner 20. At the base end of the coil liner 20, the mixing prevention circuit 3 described above is provided.
A rubber hose 17 from 5 is connected. As shown in FIG. 2, the torch nozzle 21 includes a nozzle body 22 made of a cylindrical oxygen-free copper, a wire support portion 23 screwed to the tip of the coil liner 20 and concentrically arranged inside the nozzle body 22, The nozzle main body 22 is mainly configured by an air blow adapter 24 made of aluminum, which is arranged at two places on the bottom side outer periphery of the nozzle body 22 so as to face each other.

A cylindrical carbon covering portion 25 with a flange is screwed to the tip end side opening of the nozzle body 22. The covering portion 25 is arranged so as to cover the inner peripheral surface from the tip of the nozzle body 22 to the inner side of the predetermined portion. Since the covering portion 25 is screwed, the nozzle body 22
It is removable with respect to. The wire support portion 23 is arranged on the inner peripheral side of the nozzle body 22, and forms an annular passage 34 with the nozzle body 22. Wire support 23
Is composed of a tip body 23a screwed to the coil liner 20 and a contact tip 23b screwed to the tip of the tip body 23a. The tip of the contact tip 23b extends further than the tip of the nozzle body 22. A wire hole 27, which has a diameter substantially the same as the diameter of the wire and extends in the longitudinal direction of the torch, is formed in the wire supporting portion 23 so that the welding wire 26 is inserted therethrough. The wire hole 27 supports the welding wire 26 movably in the axial direction. This wire support 23 is used for the welding power source 2
Is electrically connected to and has a function as a welding electrode. Further, the tip body 23a of the wire support portion 23
A hole 28 having a diameter larger than that of the wire hole 27 is formed therein. This hole 28 is a hole 29 in the coil liner 20.
Is in communication with. At the tip of the hole 28, the wire support 23
Eight communication holes 30 communicating with a space 34 formed by the outer peripheral surface of the nozzle body 22 and the inner peripheral surface of the nozzle body 22 are formed.

An insulating bush 45 made of an insulating resin is screwed to the outer periphery of the wire supporting portion 23 on the base side. The base of the nozzle body 22 is screwed to the outer circumference of the insulating bush 45. In the nozzle body 22, two air introduction ports 31 are formed around the shoulder portion of the insulating bush 45 so as to penetrate in the radial direction and face the insulating bush 45.

Each air blow adapter 24 has a bolt 46.
Is fixed to the outer circumference of the nozzle body 22. Since the air blow adapter 24 is provided at two places, the flow rate supplied from the air blow adapter 24 is increased. An air supply port 32 is provided at the end of the air blow adapter 24.
Is formed, and an air introduction hole 33 that connects the air introduction port 31 and the air supply port 32 is formed inside.
The air introduction hole 33 has a larger diameter than the hole 28 of the chip body 23a. The air supply port 32 is a rubber hose (not shown).
It is connected to the mixing prevention circuit 35 via. Here, since the air blow adapter 24 is attachable / detachable to / from the nozzle body 22, the air blow adapter 24 can be removed when the nozzle body 22, which is a consumable item, is replaced. Therefore, the air supply unit from the outside, which was conventionally wasted, is not wasted.

The mixing prevention circuit 35 is a circuit for preventing air from being mixed in the shield gas during welding. As shown in FIG. 3, the mixing prevention circuit 35 includes a shield gas opening / closing valve 3 for opening / closing the shield gas supplied from the gas supply source 3.
9 and 40, air on-off valves 41 and 42 for opening and closing high pressure air from the air source, and mixing prevention valves 43 and 44 connected to the air on-off valves 41 and 42, respectively.
The shield gas on-off valves 39 and 40 are, for example, direct-acting type 2
The air on-off valves 41 and 42 are port valves, and are, for example, pilot type two-port piston drive valves. The mixing prevention valves 43 and 44 are, for example, 3-port poppet type valves. The shield gas on-off valve 39 and the mixing prevention valve 44 are connected to the air connection port (not shown) of the coil liner 20 via the rubber hose 17. The shield gas on-off valve 40 and the mixing prevention valve 43 are connected to the air supply port 32 of the air blow adapter 24 via a rubber hose.

The control unit 14 includes a microcomputer including a CPU, ROM, RAM and the like. As shown in FIG. 4, a remote controller 15, a feed roller 13, shield gas on-off valves 39 and 40, air on-off valves 41 and 42, mixing prevention valves 43 and 44, and other input / output devices are connected to the control unit 14. Has been done. With the above structure, the operator can easily change various operation settings via the remote controller 15. For example, the welding time per time, the timing and time for injecting the spatter blowing air after welding,
The injection timing and time of the preflow gas can be set to optimum values according to the conditions.

Next, the operation of the above embodiment will be described. In this embodiment, spatter is removed every time welding is completed. Specifically, 1 cycle is welding (shield gas injection) → spatter removal (high pressure air injection)
→ The residual air is expelled (shield gas injection). At the time of welding, the air on-off valves 41 and 42 are shut off and the mixing prevention valves 43 and 44 are exhausted. Then, the shield gas on-off valve 40 is opened and the air blow adapter 2
The shielding gas is supplied to the air supply port 32 of No. 4. The shield gas enters the nozzle body 22 through the air inlet 31 and further moves to the tip side through the annular passage 34. As a result, the shield gas supplied from the gas supply device 3 is ejected from the tip of the torch nozzle 21. This interrupts the melt and the air during the welding operation.

At the time of welding, the mixing prevention valves 43 and 44 are both in the exhaust state. Even if air leaks from the air opening / closing valves 41 and 42, the leaked air is exhausted by the leak prevention valves 43 and 44. As a result, air is not supplied to the torch 5 during welding. If spatter occurs during this welding,
A part of it tends to adhere to the tip of the nozzle body 22, but since the carbon covering portion 25 is arranged at the tip of the inner peripheral side of the nozzle body 22, the generated spatter is less likely to adhere.

After the welding is completed, for example, after waiting for the work to move away from the torch 5 for a predetermined time, the air opening / closing valve 41 is opened and the mixing prevention valve 43 is opened. Further, the shield gas on-off valve 40 is turned off. As a result, the high pressure air from the air source is supplied to the air supply port 32 of the air blow adapter 24. The air supplied to the air supply port 32 passes from the air introduction port 31 on the side surface of the nozzle body 22 to the annular passage 34 on the inner peripheral side of the nozzle body 22.
Is supplied to. Then, the air supplied to the annular passage 34 blows off the spatter attached to the covering portion 25. Also,
Since air cools each part of the torch 5, spatters generated during the next welding are less likely to adhere to each part. The temperature of each component is preferably about 100 ° C. or lower. If it is 60 ° C, the amount of spatter adhered is greatly reduced.

The air blow adapter 24 is used for the nozzle body 2
2 is attached from the outside, the hole diameter is increased and the flow rate is increased. Therefore, the spatter attached to each part can be reliably removed in a short time. In addition, since the flow rate of air is large, cooling of each component progresses, and spatter is less likely to adhere. Furthermore, since the air introduction port 31 faces the shoulder portion of the insulating bush 45, air is directly jetted to the shoulder portion of the insulating bush 45. Insulation bush 45
Is a portion to which spatter easily adheres, and blowing the spatter by directly applying air to this portion has excellent effects in terms of improving the durability of the insulating bush 45 and preventing deposition of spatter.

By using this torch 5, it is possible to prevent the adhesion of spatter with a simple structure in which the carbon coating portion 25 is arranged at the tip and high-pressure air is supplied.
Therefore, the weight of the torch nozzle 5 can be reduced, and the capacity of the automation device when automated can be reduced. Further, since the carbon covering portion 25 is detachably attached by screwing, when the sputter adhesion performance deteriorates, it is possible to obtain a long-term spatter removing effect by replacing it. Further, since the air is prevented from being mixed with the shield gas during welding, it is possible to prevent the generation of blow holes due to the mixing of air.

When the blowing out of the sputter is completed after a lapse of a predetermined time, the shield gas on-off valve 40 is opened, the air on-off valve 41 is shut off, and the mixing prevention valve 43 is shut off. As a result, the shield gas is supplied to the air supply port 32. This shield gas expels the air remaining in the air introduction hole 33 and the annular passage 34 toward the tip side of the torch 5, and creates a shield gas atmosphere in the annular passage 34. As a result, residual air is not jetted from the tip of the torch 5 at the next welding. Since the shield gas for preflow is supplied from the air blow adapter 24 attached from the outside of the nozzle body 22, the flow rate is high. Therefore, the residual air can be reliably expelled in a short time.

In this embodiment, since the spatter can be sufficiently removed by various structures, it is not necessary to stop the welding machine every predetermined time and manually remove the spatter as in the conventional case. As a result, the operating rate of the welding machine is improved. It is also possible to operate the welding machine automatically without stopping for 24 hours. Second Embodiment Each of the air blow adapters 24 of the torch 5 for arc welding machine shown in FIG. 5 has a protrusion 47 extending toward the tip side of the torch 5. The protruding portion 47 has a passage 47a therein which communicates with the air supply port 32. The tip of the protruding portion 47 is formed obliquely toward the nozzle body 22 side.
It is fixed to the tip side of 2. The nozzle body 22 is formed with a hole 22a passing through the inside and the outside of a portion of the nozzle body 47 corresponding to the passage 47a. The hole 22a extends obliquely and faces the contact tip 23b of the wire supporting portion 23.

With the above structure, a part of the air supplied from the air supply port 32 at the time of blowing out the spatter after welding passes through the passage 47a and the hole 22a and the contact tip 2 is formed.
Spray directly on 3b. Therefore, the contact tip 2
The spatter attached to 3b is sufficiently removed. Further, since the air is directly blown onto the contact tip 23b, the contact tip 23b is cooled significantly. In the past, when the diameter of the wire hole 27 widened due to the increase in temperature of the contact tip, the wear due to sliding with the wire 26 was likely to proceed. When the diameter of the wire hole 27 was increased, the wire support portion 23 had to be replaced. However, in this embodiment, since the contact tip 23b is sufficiently cooled, the life of the wire supporting portion 23 is extended. [Modifications] (a) Although high-pressure air is not supplied to the holes 29 of the coil liner 20 in the above-described embodiments, the high-pressure air may be supplied to the holes 29 at the same time as being supplied to the air supply port 32. Then, the hole 29
The high-pressure air supplied to the air passes through the communication hole 30 and further moves in the annular space 34 toward the tip side of the torch. In this way, the high-pressure air supplied to the holes 29 serves to send out the sputters in the annular space 34 in the longitudinal direction of the torch 5. On the other hand,
The high-pressure air supplied to the air supply hole 32 of the air blow adapter 24 is directly jetted to a portion where a large amount of spatter adheres to separate the spatter from each portion. In this way, both the separation of the sputters and the delivery of the separated sputters are performed, and since the flow rate in the traveling direction of the annular space 34 is increased, the sputters in the annular space 34 are efficiently removed. (B) In the above embodiment, the air blow adapter 24 is detachably fixed to the nozzle body 22, but it may be detachably fixed to the coil liner 20. In that case, it becomes easy to remove and replace the air blow adapter 24. (C) In the above-described embodiment, the spatter is removed every time welding is performed, but the spatter may be removed after performing the welding a plurality of times. Even in that case, if the present invention is used, spatter can be sufficiently removed. (D) Although high-pressure air is used as the gas for removing spatter, other gas such as nitrogen gas may be used. (E) In the above-mentioned embodiment, the tip of the covering portion 25 may be rounded to be chamfered. This can further reduce spatter adhesion.

[0027]

In the gas shielded arc welding machine according to the present invention, the timing for supplying the gas for removing spatter is changed by the timing changing means. Therefore, spatter can be sufficiently removed even if the conditions change. When the timing changing means includes the input means, the storage means, and the control means, the change is ready and the configuration is simplified.

[Brief description of drawings]

FIG. 1 is a side view of an inert gas shielded arc welder adopting a first embodiment of the present invention.

FIG. 2 is a partial sectional view of a torch.

FIG. 3 is a circuit diagram of a mixed gas prevention circuit.

FIG. 4 is a block diagram showing a control configuration of the present invention.

FIG. 5 is a diagram corresponding to FIG. 1 in the second embodiment.

[Explanation of symbols]

 1 Inert Gas Shield Arc Welder 3 Gas Supply Device 5 Torch 14 Control Unit 15 Remote Control 21 Torch Nozzle 22 Nozzle Body 23 Wire Support 24 Air Blow Adapter

Claims (2)

[Claims] 1. A gas shielded arc welder for performing arc welding in a shield gas atmosphere by a continuously supplied wire-shaped filler material, the filler material extending in one direction and supporting the filler material. A torch having a filler material supporting portion and a cylindrical nozzle portion arranged around the filler material supporting portion with a space, and a shield gas is supplied between the filler material supporting portion and the nozzle portion. A shield gas supply unit for supplying the gas, a gas supply unit for supplying a gas for spatter removal between the filler material support unit and the nozzle unit, and a timing at which the supply timing of the gas supply unit can be changed A gas shielded arc welder equipped with a changing means. 2. The timing changing means includes an input means for an operator to input the timing, a storage means for storing the timing input by the input means, and the gas supply section according to the timing stored by the storage means. The gas shielded arc welder according to claim 1, further comprising a control means for supplying gas to the.