JPS5985372A - Wire fusing method at end of pulse arc welding - Google Patents

Abstract

PURPOSE:To generate easily an arc at the time of rewelding by supplying a fusing current exceeding the fusing energy, to a wire whose tip part is deposited once to a base metal, separating this wire from the base material, and also making its tip sharp. CONSTITUTION:When welding is ended, fusing currents 102, 104 or 106 having energy exceeding the fusing energy are supplied to a wire whose tip part is deposited once to a base metal, the wire is overheated and cut in an adjacent position of a boundary to the base metal, and also the cut tip is made sharp. In this state, a fusing current 102 sets a peak value of a pulse current higher than a peak value at the time of arc welding, also a current 104 sets pulse width of the pulse current more widely than pulse width at the time of arc welding, and a current 106 sets pulse frequency of the pulse current higher than pulse frequency at the time of arc welding. As a result, the wire is separated easily, and the welding work efficiency is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wire fusing method at the end of pulsed arc welding, and more particularly to a wire fusing method at the end of pulsed arc welding for cutting off the wire welded to the base metal at the end of welding.

In pulsed arc welding, a pulsed arc current is supplied to the arc welding wire or tip, arc discharge is generated between the arc welding wire or tip and the base material, and the arc heat melts the shear arc welding wire onto the base material, causing the base metal to melt. Pulsed arc welding is widely used in various manufacturing departments because it connects and fixes a desired member to a material, is easy to work with, and has excellent mechanical properties at the joint.

This type of pulsed arc welding usually involves supplying a pulsed arc current formed by a pulsed current 100 and a pace electric current m, 200 to an arc wire V as shown in FIG. Arc 30 between and base metal 12
Generating 0 is done as well.

On the other hand, welding is stopped by turning off the base current 200. That is, during the welding end period T in which the base current is turned off, only the pulse current 100 is supplied to the wire 10, so that the arc 300 is interrupted during the base period. and pulse current 1
00 alone does not have enough energy to generate the arc 300, and stopping the welding is achieved by turning off the M mJ pace current 200.

Generally, the on/off switch of the base current 200 is linked to the switch of the wire feeder.

Therefore, due to the OFF action of the base current 200, the feeding device for the wire wire 10 is also turned off, and the wire feeding motor is stopped. However, it is difficult for this motor to suddenly stop feeding the shear wire 10 due to the rotational inertia of the wire feed drum (i), and for this reason, the wire 10 continues to be fed even though the base current 200 is turned off. As a result, as shown in FIG. 2, the tip of the wire 10 comes into contact with the surface of the base material, and the tip of the wire is welded and fixed to the base material 12.

If the wire 10 is welded and fixed to the base metal surface in this way, it will be difficult to melt and separate the wire 1° from the base metal 12 because the energy of this current is small depending on the pulse current 100 at the end of welding. Therefore, as shown in FIG. 4, the wire 1o has to be cut off using a tool such as a bench, which is a troublesome task.

In addition, when such pulse arc welding is automatically performed by a robot or the like, as described above, the wire 10 and the base if
As a result of A12 being welded and fixed, there were problems such as damage to the welding torch when the welding torch was moved to another welding location.

In order to eliminate such problems, even if the wire feeding motor can be forcibly stopped suddenly at the end of welding, in this case the wire tip will not come into contact with the base metal 12 and a certain gap will be maintained. In order to stop the arc wire, the tip of the arc wire is made into a spherical shape, and as a result of the sludge At l (: + fringe) accumulating on this spherical surface, an arc 300 is generated from the wee V tip during rewelding. After a long time, 1 ton of waste becomes 0, and for this reason, it is necessary to remove the sludge from the previous method.
I had a weak point, such as being angry.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to easily cut the wire welded to the motherboard H, and to sharpen the tip of the wire. An object of the present invention is to provide a method for arc wire welding at the end of pulsed arc welding, which can facilitate the generation of arc at the time of remelting.

In order to achieve the above-mentioned object, the present invention applies a welding flow of more than the welding energy of the wire to the wire whose tip is once melted to the base metal at the completion of cutless arc welding. 0
1. It is characterized by supplying the wire to cut the wire from the fJ edge and sharpening the tip of the wire V.

Below ■! A preferred embodiment of the present invention will now be described with reference to J1.

The characteristics of the present invention are as described above (at the end of pulse arc welding, that is, at the end of welding 11).
The pulse peak current value is increased in (1), and a fusing current having an energy greater than the cutting energy of the wire Km is supplied by the tl to cut the wire welded to the R1 material.

In the method of the present invention, even when the motor is turned off at the end of welding, the shear arc wire is fed in a small amount by its rotational inertia, and the tip of the arc wire contacts the base metal, and both are welded and fixed. .

When these two are welded and fixed, a fusing current having an energy higher than the fusing energy is supplied to the wire, and by this, the shear wire is overheated and fused at a position r~ near the boundary with the base metal, and the cutting of both +"iiCt is achieved. do.

The above melt 1t'fr? U, dissolve the energy of flow if: I? For K, which increases more than energy, various methods can be considered, and 51
If the welding conditions are met, an appropriate method will be adopted.

Fusing in the first embodiment? 11. Flow 102 is #rg
As shown in Fig. 5, the pulse current consists of a pulse 71 + f, and the peak value of this pulse current is higher than the peak 114 during normal welding, thereby causing the wire to have an IF;
A fusing current 102 greater than the IJT energy can be supplied.

Further, in the second embodiment, the molten II 1041r
, f, ≧゛The pulse current shown in Figure B6 is made, and while the pulse peak value of this fusing current 104 is made almost the same as the pulse peak value during normal welding, the fusing current 104
The pulse width is made wider than the pulse width during normal welding,
This makes the energy of the fusing current 104 greater than the fusing energy.

Furthermore, the fusing current 106 in this third embodiment is made of a pulsed current shown in FIG. It is possible to make the energy higher than the fusing energy.

The separation of the wire from the base metal at the end of welding in each of the above-mentioned rows is caused by a fusing electric current or current having an energy greater than the fusing energy of the wire.
6. This makes it possible to easily separate the shear wire and improve welding work efficiency, and it can also be effectively applied to automatic welding by robots, etc. can.

In addition, by cutting the wire that has once melted into the base material by cutting it, it is possible to remove the tip of the wire. It is possible to sharpen the W fracture surface, and no green matter such as sludge adheres to the sharpened fracture surface.As a result, it is possible to reduce the occurrence of Boo 23000 during rewelding. can be carried out extremely easily.

As explained above, according to the present invention, it is possible to very easily transfer the base metal (blackened wire) at the end of welding.
] Therefore, even in automatic welding operations such as robots, it is possible to eliminate the damage caused by conventional torches (M, etc.) by 1'1.
It becomes possible to leave the room.

Furthermore, as mentioned above, since the wire is cut by fusing, it is possible to sharpen the tip of the wire, which greatly facilitates arc generation during rewelding. becomes possible.

[Brief explanation of the drawing]

Figure 1 shows the pace current waveform at the end of conventional pulsed arc welding, Figure 2 shows the normal welding state of pulsed arc welding, and Figure 3 shows the wire and base metal at the end of welding. A schematic explanatory diagram showing the welded state of FIG. 4 shows a state where the wire is separated from the base material (t7.
FIG. 5 is a waveform diagram of a first embodiment of the fusing current supplied at the end of welding according to the present invention, FIG. 6 is a waveform diagram of a second embodiment of the fusing current supplied at the end of welding according to the present invention, and FIG. FIG. 7 is a waveform diagram of a third embodiment of a fusing current supplied at the end of pulsed arc welding according to the present invention. In each figure, the same members VC are given the same symbols, 1o/m wire, 12 scales 4°4, ioo is pulse current, 102.10
4.106 is the fusing current, and T is the welding end JIJJ interval. Agent Patent attorney Shin Kuzuno - (#1 or 1 person)

Claims (1)

[Scope of Claims] (1) At the end of welding in consumable electrode type pulsed arc welding, the tip of the consumable electrode (wire) is once welded to the base metal, and a fusing current equal to or greater than the energy of the fusing wire 9 is supplied to the wire. A wire fusing method at the end of pulse arc welding, characterized by cutting the wire from the base metal and sharpening the tip of the wire. (2. A wire fusing method at the end of pulsed arc welding, characterized in that the wire fusing current consists of a pulsed current with a pulse peak value increased compared to that during normal welding. (3) In the method according to claim (1), the wire fusing current d: a wire fusing current at the end of pulsed arc welding, characterized in that the wire fusing current d is a pulsed current with increased pulse width. (4) In the method described in claim (1), wire fusing at the end of pulsed arc welding is characterized in that the wire fusing current consists of a pulsed current with a pulse frequency higher than that during normal welding. Method.