JPS63123572A - Gas shield arc welding torch - Google Patents

Abstract

PURPOSE:To prevent the occurrence of blowholes by performing the welding while supplying shielding gas led through a shielding gas hose from one or plural small holes bored in an electrode wire feed guide to an electrode wire feed path, too. CONSTITUTION:One or plural small holes 11 are bored in the electrode feed guide 3 and the shielding gas is supplied thereto. In this way, the stationary air in the feed guide 3 is prevented from stagnating and the blowholes of weld metal which have been so far caused by being involved in said stationary air can be prevented. The quality of the weld metal can be improved by a device with this constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a torch for gas-shielded arc welding, and particularly to a torch suitable for semi-automatic gas-shielded arc welding.

[Conventional technology]

In a conventional semi-automatic gas-shielded arc welding torch, when the shielding gas supplied from the shielding gas hose is introduced into the welding torch, it passes through the shielding gas flow path located on the outer periphery of the electrode wire feeding guide located at the center of the torch. It reaches the nozzle at the tip of the torch, where it is emitted and covers the arc, preventing atmospheric air from entering the welding area and, in turn, preventing blowholes from occurring in the weld metal.

[Problem that the invention seeks to solve]

The above conventional technology focuses only on the shield gas flow path, although there are two paths leading to the nozzle at the tip of the torch: the shield gas flow path and the electrode wire feeding path.
No consideration was given to gas shielding of the electrode wire feed path, and air may get mixed in from the electrode wire feed path.
There was a problem that it was mixed into the shielding gas discharged from the nozzle tip.

An object of the present invention is to prevent air from being mixed into the shielding gas emitted from the torch.

[Means for solving problems]

The above object is achieved by flowing shielding gas also into the electrode wire feed path.

[Effect]

A hole is drilled in the electrode wire feed guide to allow shielding gas to flow through the electrode wire feed path. Thereby, the shielding gas supplied from the shielding gas hose flows into the electrode feeding path as well as the shielding gas flow path, and air is prevented from being mixed in the shielding gas discharged from the tip of the welding torch.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1, 2, and 3. Fig. 1 shows a cross-sectional view of a semi-automatic gas-shielded arc welding torch, and Fig. 2 shows a cross-sectional view of a semi-automatic gas-shielded arc welding torch.

1 of the nozzle part in Fig. 1, that is, the shield gas discharge port.
3 shows a detailed view of the holder part of FIG. 1, that is, the shielding gas supply part.

The torch has a nozzle 1 and inside thereof a tip 2 and an electrode wire feeding guide 3 protected by an electrode wire feeding guide cover 6, which are fed by a guide head 4.

Electrode wire supercharging guide.

It serves as a conduit for the electrode wire and continues to the holder.

A holder portion held by a welder during welding is connected to an electrode feeding guide 3, its cover 6, a shield gas hose 5, and a conduit 8, and covers these with a holder 7.

In a conventional torch, the shielding gas is supplied into the torch from the shielding gas supply hole 12 of the cover of the electrode feeding guide,
The shielding gas passes through the gap between the electrode feeding guide cover 6 and the electrode feeding guide 3, that is, the shielding gas flow path, and is emitted from the nozzle tip as shown in the flow 9 of FIG. 2, protecting the welding arc and preventing air from entering. However, as the welding torch is used more and more, 1.1 tip 2, electrode feeding guide 3. There is an increased possibility that the guide head 4 and the like will be worn and deformed, and a gap g that should not be created in the first place will occur between the tip 2 and the electrode wire feeding guide 3, as shown in FIG. Once the gap g is created, the shielding gas passes through this gap, passes through the electrode feeding guide 3 and the tip 2, and is emitted from the tip of the nozzle 18. At this time, the still air in the feeding guide Attracted by the flow of shielding gas, it becomes a flow of air 10.

Mixed into shielding gas. This trapped air is the main cause of blowholes in the weld metal.

In order to prevent such trapped air, either the generation of the gap g can be prevented, or the air in the electrode feeding guide 3 can be replaced with a shielding gas.

In order to achieve the latter purpose, which is difficult to prevent considering the current holder structure and the heavy labor involved in welding work, it is necessary to provide a sealing gas supply hole 11 in the electrode feeding guide as shown in Fig. 3. That's fine.

That is, according to this embodiment, in a gas-shielded arc welding torch, shielding gas is provided in both the shielding gas flow path leading to the nozzle tip, which is the outlet of the electrode wire and shielding gas, and the electrode wire feeding path. This has the effect of preventing air from getting mixed in.

〔Effect of the invention〕

According to the present invention, it is possible to prevent air from entering the gas-shielded arc welding torch, and the welding arc can be protected by the shielding gas having the desired composition. It is possible to prevent blowholes from occurring.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a semi-automatic gas shielded arc welding torch according to an embodiment of the present invention, Fig. 2 is a detailed view of the nozzle part of Fig. 1, and Fig. 3 is a detailed view of the holder part of Fig. 1. It is. DESCRIPTION OF SYMBOLS 1... Nozzle, 2... Chip, 3... Electrode feeding guide, 4... Guide head, 5... Shield gas hose, 6... Electrode feeding guide cover, 7... Holder,
8... Conduit 1, 9... Shield gas flow,
DESCRIPTION OF SYMBOLS 10... Flow of trapped air, 11... Hole for shielding gas supply of electrode feeding guide, 12... Hole for supplying shielding gas of electrode feeding guide cover.

Claims (1)

[Claims] 1. In a gas-shielded arc welding torch, one or more small holes are made in the electrode wire feeding guide, and the shielding gas guided from the shielding gas hose connects to the electrode wire feeding path and the shielding gas located on the outer periphery thereof. A gas-shielded arc welding torch characterized by being configured so that flow flows in both sides of the flow path.