JPS6317584Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an improvement of a wire guide for a hot wire arc welding torch, particularly a wire guide through which a wire is fed.

The so-called hot-wire non-consumable electrode arc welding method, in which a current is passed through the wire and the wire is heated by the I ² R heat generated while feeding it to the arc section, has already been published in Japanese Patent Publication No. 19731/1973. Disclosed. With this method, the amount of welding can be greatly increased compared to the case where the wire is fed without heating, but it requires two relatively large torches: an arc generating torch and a wire heating torch. Therefore, it was not suitable for manual welding. That is, in order to enable manual welding, it was necessary to integrate the two torches and to reduce the size to a practical extent. In order to achieve this miniaturization, it is best to fix the wire heating torch section parallel to the TIG torch, with only its tip inclined toward the TIG torch side, and a conventional device as shown in Fig. 1 has been provided. Ta.

In the figure, 1 is a TIG torch, which holds a tungsten electrode 2 aligned with its axis. A shield nozzle 3 shields the arc 6 and the molten pool 23 with a shielding gas 7. 4 is a holder that holds the wire heating torch part.
It is fixed to the TIG torch 1. Reference numeral 9 denotes a cylindrical slide base in which the slide piece 8 moves up and down, and is fixed to the holder 4. 12 is an adjustment nut, slide base 9
It is located in the notch part and is screwed into a male screw cut in the upper part of the slide piece 8. Therefore, when the adjusting nut 12 is rotated, the adjusting nut 12 does not move up and down, but only the slide piece 8 moves up and down. Further, at this time, a guide groove for preventing rotation is cut in the slide piece 8, and a knob 11 attached to the slide base 9 is engaged with this guide groove. A guide cover 16 is screwed onto the lower part of the slide piece 8 so that its extension line is directed toward the electrode 2. An insulating guide 15 is inserted into the guide cover 16, and an insulating spacer 10 is similarly inserted into the slide piece 8. These insulating guides 15 and insulating spacers 10 include
A hole with a small diameter commensurate with the diameter of the wire for electrically insulatingly feeding the wire 5 to the arc 6 section is provided. 18 is a power supply fitting, in the center of which is a conduit cable 20.
is installed. 17 is a copper wire, one end of which is brazed to a power supply fitting 18 and the other end connected to a wire heating power source 21. In addition, the power supply fitting 18 includes
The power supply chip 13 is screwed together via the insulating cap nut 14. This cap nut 14 can be screwed onto the slide piece 8 to connect the power supply chip 13.
And the power supply fitting 18 is installed in an electrically insulating manner.
Note that 19 is an insulating tube of the power supply fitting 18.
In the figure, 22 is the base material for welding, 6 is the arc generated between the base material 22 and the electrode 2, and 23
is a molten pool 23 formed by the arc heat.

Next, the operation and operation of this conventional device will be explained. First, the adjustment nut 12 screwed onto the slide piece 8 is rotated to move the slide piece 8 up and down.
The positional relationship between the tip of the wire 5 and the tip of the electrode 2 is adjusted to an appropriate value. Thereafter, the wire 5 fed from the wire feeding device (not shown) to the conduit cable 20 passes through the power feeding chip 13, is guided by the insulating spacer 10 and the insulating guide 15, and is introduced into the molten pool 2.
Sent to 3. On the other hand, the wire heating current is supplied from the wire heating power supply 21 to the power supply chip 13 via the copper wire 17 and the power supply fitting 18, and is supplied to the wire 5 by this power supply chip 13. Since the wire 5 is insulated by the insulating spacer 10 and the insulating guide 15, all the wire heating current is applied to the wire 5.
It flows through the molten pool 23, the base material 22, and the wire heating power source 21. At this time, wire 5
is resistively heated to near its melting point by the resistance from the lower end of the power supply chip 13 to the molten pool 23 and the current flowing between them, and is easily melted by the heating by the arc 6 and the heat retained in the molten pool 23, and the Material 2
It will be welded to 2. Since the tip of the wire 5 is heated to near the melting point in this manner, the insulating spacer 10 and the insulating guide 15 are made of a material having heat resistance and insulating properties, such as ceramic. However, since ceramic is made into a product by sintering its raw materials, products like the insulating guide 15, which are hollow, thin, and long, are marked with "A" as shown in Figure 2. There are many things that are deformed. When this deformed insulating guide 15 is installed in the guide cover 16 as shown in FIG. 3, the insulating guide 15 is broken due to the resistance etc. when the wire 5 passes through the insulating guide 15, and the broken part 15a is a molten pool. It falls on part 23.

Furthermore, during welding, the guide cover 16 and the lower end of the insulating guide 15 become red hot, and the insulating guide 15 may crack due to the heat shock.

Since the wire guide of the conventional hot wire type arc welding torch is constructed as described above, the insulated guide 15 is easily broken due to the feeding resistance of the wire 5, heat shock, etc., and if it falls into the molten pool 23, the arc will break. 6 not only disappears, but also causes welding defects. Further, when manufacturing the insulated guide 15, many defective products were produced due to the large strain "A" and could not be installed in the guide cover 16, and the cost of the insulated guide increased.

This idea was made in order to eliminate the drawbacks of the conventional ones as mentioned above. By dividing the insulating guide inside the guide cover into multiple parts, the length of each insulating guide can be shortened, and the distortion during baking molding can be reduced. An object of the present invention is to provide a wire guide for a hot wire type arc welding torch equipped with an insulated guide that hardly generates.

An embodiment of this invention will be described below with reference to the drawings.

a base member 24 of the insulated guide and its tip member 25;
Since the components other than the guide cover 26 and the guide cover 26 are the same as the conventional one, the explanation thereof will be omitted.

Reference numeral 26 denotes a guide cover, which is screwed onto the slide piece 8 and arranged so that its extension line faces the electrode 2.
Inside the guide cover 26, an insulating guide base member 24 is provided on the inlet side of the wire 5, and a separately molded insulating guide tip member 25 is provided on the outlet side. Further, a stepped portion is provided at the lower end of the guide cover 26 to prevent the tip member 25 from falling into the molten pool 23 portion.

FIG. 5 shows the relationship between the outer diameter "D" and the overall length "L" of the insulating guide base member 24 and the tip member 25.
Thin-walled cylindrical ceramic parts generally undergo greater deformation as their length increases. The guide parts used in the hot wire arc welding torch according to this invention are easily deformed by the heat of the arc 6 and the resistance heating of the wire 5, and are also affected by heat shock, so the base part of the insulated guide 24 and the tip member 25, each total length “L” is
It is desirable to make it 7D or less. Guide cover 2
When the total length of the guide cover 6 is long and the relationship between the total length and the outer diameter of the base member 24 and tip member 25 of the insulating guide is L>7D, the insulating guide inside the guide cover 26 is further divided into a plurality of parts.

Note that the reason for providing a portion with a large outer diameter on the outer periphery of the base member 24 of the insulating guide is to provide a tapered portion on the entrance side of the inner diameter to facilitate guiding of the wire 5. This is to prevent the base member 24 and tip member 25 of the insulating guide from being inserted incorrectly.

As described above, according to this invention, by dividing the insulated guide arranged inside the guide cover into multiple parts, it is possible to prevent damage to the insulated guide due to wire feeding resistance, heat shock, etc. The defect rate during manufacturing can be reduced. In addition, by making the inner diameter of the lower end of the guide cover smaller than the outer diameter of the insulating guide, even if the insulating member breaks, it will not fall into the molten pool, extinguishing the arc, or causing welding defects. There is an effect.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view showing a conventional hot wire type arc welding torch, Fig. 2 is a detailed sectional view showing a conventional insulated guide, and Fig. 3 is a detailed view of the wire guide section of a conventional hot wire type arc welding torch. FIG. 4 is a front sectional view showing a hot wire type arc welding torch according to an embodiment of this invention, and FIG. 5 is a detailed sectional view of a wire guide according to this invention. 1... TIG torch, 2... Electrode, 3... Nozzle, 4... Holder, 5... Wire, 6... Arc, 7... Shield gas, 8... Slide piece, 9
...Slide base, 10 ...Insulating spacer, 1
1...Knob screw, 12...Adjusting nut, 13...
... Power supply chip, 14 ... Cap nut, 15 ... Insulated guide, 16 ... Guide cover, 17 ... Copper wire,
18...Power supply fitting, 19...Insulation tube, 20
. . . Conduit cable, 21 . . . Wire heating power source, 22 .

Claims (1)

[Claims for Utility Model Registration] (1) A wire heating device that includes a TIG torch and a wire guide fixed to the TIG torch that guides the wire toward a molten pool created on the base material by an arc at the tip. In the hot wire arc welding torch, the wire guide is configured by arranging a cylindrical insulating guide made of a heat-resistant insulating material such as ceramic and having a wire guide hole inside a cylindrical guide cover, A hot wire type arc welding torch, characterized in that the insulated guide is formed by dividing into a plurality of parts in the longitudinal direction. (2) The hot wire type arc welding torch according to claim 1, which is characterized in that the lower end of the guide cover is provided with a stepped part for preventing the insulated guide from falling. (3) Total length “L” of each member of the divided insulation guide
The hot wire arc welding torch according to claim 1, wherein the relationship between L and outer diameter "D" is L≦7D.