JPH0211276A - Welding torch - Google Patents

Abstract

PURPOSE:To prevent spatters from sticking and depositing on nozzles by providing a vibrator to vibrate the nozzles. CONSTITUTION:When electromagnets 37 and 38 are excited alternately, an armature part 35a is attracted to the electromagnets 37 and 38 alternately and vibrating pieces 35 turn reciprocatively clockwise and counterclockwise in the prescribed angular range with a wire 13 as a center. Nozzle bases 36 are fixed on the vibrating pieces 35 and when the vibrating pieces 35 turn reciprocatively, the nozzle bases 36 and the nozzles 11 also turn reciprocatively. By this method, the spatters can be prevented from sticking and depositing on the nozzles by simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas-shielded arc welding torch that prevents spatter adhesion and deposition.

In gas-shielded arc welding, especially CQ2 welding, spatter occurs frequently, and this spatter adheres and accumulates on the inner and outer surfaces of the gas nozzle tip. Figure 4 is a diagram explaining this adhesion and deposition situation.
ta) is the early stage, fb) is the middle stage, and (C) is the late stage. In this figure, 10 is a torch, 11 is its nozzle, 12 is a contact tip, 13 is a welding wire, 14 is a welding bead, 1
5 is a material to be welded.

Shielding gas is supplied to the weld through the gap between the contact tip and the nozzle. Part of the spatter generated during welding collides with the nozzle tip, and adheres to and accumulates on the nozzle tip. Reference numerals 16a, 16b, and 16c show the sputters that are gradually attached and deposited. When spatter adheres and accumulates on the inside of the nozzle, it narrows the nozzle opening and causes turbulent flow of the shielding gas, and the outside air shielding effect becomes insufficient, resulting in the formation of pores in the weld, and nitrogen infiltrates, causing damage to the weld metal. Physical properties, especially toughness, may deteriorate. Furthermore, as the deposition of spatter at the nozzle tip progresses, the deposited spatter fuses together to form a ring, which detaches from the nozzle tip due to some kind of vibration, thermal expansion/contraction, etc. during welding, and falls onto the welding part. This will disturb the bead shape. Therefore, this type of torch requires measures against adhesion and deposition of spatter.

(Conventional technology) Various countermeasures against torch sputter adhesion have been proposed.

One of them is changing the type of gas. CO2 gas A
By changing to r-Co 2 mixed gas, the arc becomes stable and the amount of spatter generated is significantly reduced compared to the case of CO 2 gas. However, Ar-Co2 mixed gas welding is weak against wind.
Shielding properties are inferior to CO2 welding.

In addition, arc light and radiant heat are stronger than in CO2 welding, and there are problems such as the welder being easily fatigued.

The other method is to scrape off the attached spatter, and a tool for scraping off the attached spatter is provided on the inner wall of the nozzle, and this is operated by an air cylinder. Figure 5 also shows this system, with a guide plate 171 and an elastic scraping rod 1 in a part of the welding workshop.
8. A motor part 19 for rotating this is prepared, and when the welding work has elapsed for a predetermined period of time (as in al), the torch 10
is moved onto the hole 17a of the guide plate 17, and then pressed down. As a result, the torch and the guide plate 17 descend as shown in (b), and at this time, the scraping rod 18 protrudes from the hole 17a.
enters the inside of the torch. In this state, when the motor is started and the scraping rod 18 is rotated, the rod 18 scrapes off the spatter that has adhered and accumulated on the inner surface of the torch.

This method of scraping off adhering spatter requires welding to be interrupted at regular intervals, which lowers the operating rate. In addition, there is a risk of scratching the inner surface of the nozzle during scraping, and if scratches occur, spatter adhesion is promoted, and if the nozzle is made of graphite or ceramic, cracks are likely to occur. The spatter is firmly attached to the nozzle, and the attached spatter cannot be easily scraped off.

[Problem to be solved by the invention]

As described above, various measures have been taken to prevent spatter adhesion from torches, but none have been fully satisfactory.

SUMMARY OF THE INVENTION An object of the present invention is to provide a welding torch that makes it difficult for spatter to adhere and does not cause problems such as nozzle constriction or sputtering falling off during a predetermined welding work time of, for example, 30 minutes. be.

[Means to solve the problem]

As shown in FIG. 1, in the present invention, a gas-shielded arc welding torch 10 is provided with a nozzle vibrating device 20.

As in all the figures, the same parts as in other figures are given the same reference numerals, 13 is a welding wire, and 15 is a material to be welded. Further, 21 is a welding power source, 22 is a control device, and 23
2 is a gas cylinder that supplies shielding gas, 24 is a reel that is a supply source of welding wire, and 25 is a wire feeding roller.

[Effect]

In this configuration, since the nozzle of the welding torch 10 is vibrated during welding by the imaging device 20, spatter is prevented from adhering, and rapid spatter deposition can be avoided.

Welding work is carried out as usual, connecting the power supply line from the welding power source 21 to the base metal 15 and the welding wire (contact tip),
Welding is performed by supplying shielding gas from the gas cylinder 23 and welding wire from the reel 24 to the torch.

〔Example〕

Embodiments of the present invention are shown in FIGS. 2 and 3. Figure 2 shows a type in which the nozzle 11 is reciprocally rotated within a predetermined angle range.
is its vibrating (reciprocating rotation) piece, 35a is its armature part,
It protrudes between a pair of electromagnets 37 and 38. When these electromagnets 37 and 38 are alternately excited, the armature portion 35a is alternately attracted to the electromagnet 37 and the electromagnet 38, and as a result, the vibrating piece 35 moves clockwise and counterclockwise within a predetermined angular range around the wire 13. It rotates back and forth. 31 is a torch base, electromagnets 37 and 38 are attached to the torch base 3I by arms 39, and the vibrating piece 35 is fitted into an arcuate groove provided in the torch base 31. A nozzle base 36 is fixed to the vibrating piece 35, so when the vibrating piece 35 rotates back and forth, the nozzle base 36 and the nozzle 11 also rotate back and forth. 33 is a shielding gas supply port provided in the wire guide 32.

FIG. 3 shows a type in which the nozzle 11 is vibrated left and right. The protrusions of the vibrating pieces 45 fit into the radial grooves of the torch base 31, and when the electromagnets 41 and 42 are alternately excited, the vibrating pieces 45 are alternately attracted to the electromagnets 41 and 42, and the radial direction It moves back and forth. The vibrating piece 45 has a nozzle base 3
6 is fixed and the nozzle 11 is screwed into the nozzle base 36, so that the nozzle 11 eventually vibrates due to the above-mentioned reciprocating movement. 43
44 is an arm for attaching the electromagnets 41 and 42 to the torch base 31.

In both Figures 2 and 3, the vibration width of the nozzle 11 is 2 to 12 dragons,
A suitable frequency is 1 to 60 Hz. The material of the nozzle may be conventionally copper, ceramic, copper or steel coated with fluororesin or ceramic. Further, the nozzle may be either a water-cooled type or a non-water-cooled type.

There are two types of gas-shielded arc welding: one that uses solid wire and one that uses wire that is flanked.The latter uses wire that generates a lot of spatter, and spatter adhesion to the nozzle becomes a problem. Especially when welding primer-resistant flux-cored wire, spatter occurs at 6 to 8 g/1I.
It also becomes Iin. Under normal welding conditions, approximately 1/3 of the generated spatter adheres to the nozzle. Therefore, 60g of spatter adheres to the nozzle in 30 minutes of welding time, and the nozzle hole is almost completely eliminated. The amount of spatter deposited by a standard torch with a nozzle tip inner diameter of 19 m is at most 20 g, and under normal conditions it is best to maintain it at 6 g or less.

The rotating type shown in Figure 2 has a vibration width of 6. On+, frequency 60H
z, The nozzle is copper with ceramic coating,
The diameter is 19mm, the height from the non-welded material to the nozzle is 20mm,
Welded with. Welding conditions are Franks wire 1.6
*Using mφ, CO2 gas shield, welding current is 320
A. The welding voltage was 28V, and the welding position was horizontal fillet robot welding. The welding results showed that after 30 minutes of welding, there was almost no progress in spatter deposition on the nozzle, and the amount of spatter deposited after welding was 2.4g, so there was no problem with gas shielding.
There was no falling of spatter lumps.

〔Effect of the invention〕

As explained above, in the present invention, spatter adhesion and deposition on the nozzle can be suppressed by the simple means of vibrating the nozzle, and the present invention is effective when used in gas shielded arc welding. For vibration generation, simple and robust structures such as electromagnets, motors, and pistons powered by air or other gases can be used, and there are no problems with durability.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the basic configuration of the present invention, FIGS. 2 and 3 are schematic vertical and cross-sectional views showing embodiments of the present invention, and FIG. 4 is an explanatory diagram of sputter attachment to a nozzle. FIG. 5 is an explanatory diagram of a conventional example. In Figure 1, 10 is a welding torch, 20 is a nozzle vibrator, 1
5 is a material to be welded.

Claims (1)

[Claims] 1. A welding torch equipped with a contact tip in the center for guiding a welding wire (13), and a nozzle (11) surrounding the contact tip for supplying shielding gas to the welding area, comprising: A torch for gas shielded arc welding, characterized in that it is provided with a vibrating device (20) that vibrates a nozzle to prevent spatter adhesion and deposition.