JPH0768382A - Welding torch - Google Patents

Abstract

PURPOSE:To enhance cutting-off capacity of the outside air by shielding gas and simultaneously, to prevent the disturbance of an arc by the shielding gas. CONSTITUTION:The air is cut off by jetting the shielding gas 6 at high speed toward base metals 2 to be welded from a gas nozzle 14 for cutting-off the outside air fitted on the tip of a torch main body 1. Further, the disturbance of the arc 13 by the shielding gas 6 at high speed is prevented by introducing a part of the shielding gas 6 flowing at high speed in the gas nozzle 14 for cutting-off the air into a gas nozzle 17 for adjusting the welding environment via a gas introducing hole 18 and jetting the shielding gas 6 at low speed to the inside of the shielding gas 6 at high speed from the gas nozzle 17 for adjusting the welding environment.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a welding torch.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show a conventional welding torch.

A collet 4 for holding the welding electrode 3 toward the welding base metal 2 is provided at the position of the inner axis of the torch body 1, and the outer periphery of the collet 4 is covered with a hollow collet body 5 and the collet body 5 is covered. Collet body 5 from the rear end side
The shield gas 6 can be supplied to the inside of the collet body 5, and a gas outlet 7 for discharging the shield gas 6 from the collet body 5 to the outside is formed on the side surface of the tip portion of the collet body 5, so that the tip of the collet body 5 receives gas. A gas lens 8 covering the outlet 7 is provided, and a mesh portion 9 that allows the shield gas 6 to pass through is attached to an opening 10 formed in the gas lens 8.

Further, a gas nozzle 12 is attached to the tip of the torch body 1 so as to surround the welding electrode 3 and have a throttle 11 for injecting the shield gas 6 toward the welding base material 2.

Numeral 13 is an arc generated between the welding electrode 3 and the welding base material 2.

Then, with the collet 4 holding the welding electrode 3 toward the welding base metal 2, a welding voltage is applied between the welding electrode 3 and the welding base metal 2 from a welding power source (not shown), so that the welding electrode is welded. Arc 1 between 3 and welding base metal 2
3 is generated, the welding base material 2 is melted by the heat of the arc 13, and welding is performed.

In this state, when the shield gas 6 is supplied to the collet body 5 from the rear end side, the shield gas 6 passes through the inside of the collet body 5 and is taken out from the gas take-out port 7 formed on the side surface of the tip part. Next, the gas passes through the mesh portion 9 of the gas lens 8 and is jetted from the narrowed portion 11 at the tip of the gas nozzle 12 toward the welding base material 2.

Then, the shield gas 6 injected from the tip of the gas nozzle 12 shields the arc 13 and the groove of the welding base metal 2 from the outside air, thereby preventing the molten pool formed in the groove from being oxidized by the outside air. It

[0009]

However, the above-mentioned conventional welding torch has the following problems.

That is, conventionally, the arc 13 and the groove are shielded from the outside air by uniformly injecting the shield gas 6 from the narrowed portion 11 at the tip of the gas nozzle 12 toward the welding base metal 2. However, by doing so, the flow velocity of the shield gas 6 is increased so that the shield gas 6
However, since the arc 13 is disturbed by the high-speed shield gas 6, there is a limit to increase the flow velocity of the shield gas 6 and the outside air is sufficiently blocked. There was a problem that it was difficult to perform welding in the state.

In view of the above situation, it is an object of the present invention to provide a welding torch capable of improving the ability of the shield gas to shut off the outside air and at the same time preventing the arc from being disturbed by the shield gas. To do.

[0012]

According to the present invention, the welding electrode is surrounded by the tip of a torch body that holds the welding electrode toward the welding base metal, and the shield gas is injected at high speed toward the welding base metal. A gas nozzle for use is provided, and a gas nozzle for adjusting the welding environment that surrounds the welding electrode and injects the shielding gas at a low speed is provided inside the gas nozzle for shutting off the outside air. The welding torch is characterized in that a gas introduction hole for introducing a part of the shield gas flowing at a high speed through the gas nozzle for use is formed.

[0013]

The operation of the present invention is as follows.

The outside air is shut off by injecting a shielding gas at a high speed from the outside air shutoff gas nozzle attached to the tip of the torch body toward the welding base metal.

At the same time, a part of the shield gas flowing at high speed in the outside air shutoff gas nozzle is introduced into the welding environment adjusting gas nozzle through the gas introduction hole, and the welding environment adjusting gas nozzle is introduced to the inside of the high speed shield gas. By ejecting the low-speed shield gas, the turbulence of the arc due to the high-speed shield gas is prevented.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention.

A collet 4 for holding the welding electrode 3 toward the welding base metal 2 is provided at the position of the inner axis of the torch body 1, and the outer periphery of the collet 4 is covered with a hollow collet body 5 and the collet body 5 is covered. Collet body 5 from the rear end side
The shield gas 6 can be supplied to the inside of the collet body 5, and a gas outlet 7 for discharging the shield gas 6 from the collet body 5 to the outside is formed on the side surface of the tip portion of the collet body 5, so that the tip of the collet body 5 receives gas. A gas lens 8 covering the outlet 7 is provided, and a mesh portion 9 that allows the shield gas 6 to pass through is attached to an opening 10 formed in the gas lens 8.

Further, a torch main body 1 is provided with an outside air shutoff gas nozzle 14 surrounding the welding electrode 3 for injecting the shield gas 6 toward the welding base metal 2 at a high speed, and at the tip of the outside air shutoff gas nozzle 14, The narrowed portion 15 and the gradually expanded portion 16 are formed so that the shield gas 6 sprayed at high speed from the outside air blocking gas nozzle 14 spreads slightly as it approaches the welding base material 2.

Inside the gas nozzle 14 for shutting off the outside air,
A welding environment adjusting gas nozzle 17 which surrounds the welding electrode 3 and injects the shield gas 6 at a low speed is arranged, and the welding environment adjusting gas nozzle 17 is penetrated through the opening 10 of the gas lens 8 to support the collet body 5 by the support member 21. Fixed to
In the middle of the welding environment adjusting gas nozzle 17, a gas introduction hole 18 for introducing a part of the shield gas 6 flowing at high speed in the outside air blocking gas nozzle 14 arranged on the outer periphery is formed.
A gradually expanding portion 19 is formed at the tip of the welding environment adjusting gas nozzle 17 so that the shield gas 6 sprayed at a low speed from the welding environment adjusting gas nozzle 17 spreads slightly as it approaches the welding base material 2.

Reference numeral 13 is an arc generated between the welding electrode 3 and the welding base metal 2, and 20 is a layer thickness of the shield gas 6 on the high speed side.

Next, the operation will be described.

The welding electrode 3 is attached to the welding base metal 2 by the collet 4.
While holding it toward, by applying a welding voltage from the welding power source (not shown) between the welding electrode 3 and the welding base metal 2, an arc 13 is generated between the welding electrode 3 and the welding base metal 2. The welding base material 2 is melted by the heat of the arc 13 and welding is performed.

In this state, when the shield gas 6 is supplied from the rear end side to the collet body 5 at high speed, the high-speed shield gas 6 passes through the inside of the collet body 5 and the gas outlet 7 formed on the side surface of the front end. From the gas nozzle 1 and then passed through the net portion 9 of the gas lens 8 to block the outside air.
It is jetted vigorously from the narrowed portion 15 and the gradually expanded portion 16 of No. 4 toward the welding base material 2.

At this time, the gradually expanding portion 16 formed at the tip of the outside air shutoff gas nozzle 14 causes the shield gas 6 injected at high speed to be slightly spread as it approaches the welding base metal 2.

Then, by injecting the high-speed shield gas 6 from the tip of the outside air shutoff gas nozzle 14, the arc 13 and the groove of the welding base material 2 are shut off from the outside air by the high-speed shield gas 6.

On the other hand, a part of the shield gas 6 flowing at a high speed in the outside air shutoff gas nozzle 14 is introduced into the welding environment adjusting gas nozzle 17 from the gas introduction hole 18 by the residual pressure in the outside air shutoff gas nozzle 14. It is jetted at a low speed from the welding environment adjusting gas nozzle 17 toward the welding base material 2.

At this time, the gradually expanding portion 19 formed at the tip of the welding environment adjusting gas nozzle 17 causes the shield gas 6 injected at low speed to be slightly spread as it approaches the welding base material 2.

Then, by injecting the low-speed shield gas 6 from the welding environment adjusting gas nozzle 17 into the inside of the high-speed shield gas 6 from the outside air shutoff gas nozzle 14, the arc 1 is generated by the flow of the high-speed shield gas 6.
3 is prevented from being disturbed, and the welding environment of the groove portion is kept in an optimum state.

In this way, the shield gas 6 injected toward the groove is divided into two flows, high speed and low speed, the outside is made high speed to shut off the atmosphere, and the inside is made low speed to prevent the disturbance of the arc 13. As a result, oxidation of the molten pool is more completely prevented, and the arc 13 is more stabilized, so that it is possible to perform higher quality welding as compared with conventional welding.

Further, since it is possible to increase the layer thickness 20 of the outer high-speed shield gas 6 without disturbing the arc 13 and to further increase the flow velocity of the shield gas 6, a higher welding current is applied. It becomes possible to perform excellent welding, and it is possible to widen the width of welding.

The present invention is not limited to the above-mentioned embodiment, and the injection angle and layer thickness of the outer high-speed shield gas are arbitrary depending on the kind of welding and the kind of shield gas used. That the inner shield gas ejection speed can be arbitrarily set according to the size of the gas introduction hole, that it can be widely applied to welding torches using consumable electrodes and non-consumable electrodes, and the like. Needless to say, various changes can be made without departing from the scope of the invention.

[0033]

As described above, according to the welding torch of the present invention, it is possible to enhance the ability of the shielding gas to shield the outside air and at the same time prevent the arc from being disturbed by the shielding gas. It can be effective.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

FIG. 2 is a cross-sectional view of FIG.

FIG. 3 is a side view of a conventional example.

4 is a cross-sectional view of FIG.

[Explanation of symbols]

 1 Torch body 2 Welding base metal 3 Welding electrode 6 Shield gas 14 Gas nozzle for shutting off outside air 17 Gas nozzle for adjusting welding environment 18 Gas introduction hole

Claims (1)

[Claims] 1. A torch main body for holding a welding electrode toward a welding base material is provided with a gas nozzle for surrounding the welding electrode, and an outside air shutoff gas nozzle for injecting a shield gas at a high speed toward the welding base metal is provided at the tip of the torch body. A gas nozzle for adjusting the welding environment, which surrounds the welding electrode and injects the shield gas at a low speed, is provided inside the gas nozzle for adjustment, and the gas nozzle for adjusting the welding environment flows at high speed inside the gas nozzle for shutting off the outside air. A welding torch having a gas introduction hole for introducing a part of gas.