JPS5837068B2 - Seam welding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a seam welding method for continuously joining plate-shaped materials to be welded.

FIG. 1 is a diagram showing a conventional seam welding method.

In the figure, 1 and 2 are axes 1a and 2a, respectively.
A disk-shaped welding electrode 3 and 4 rotates around , and 3 and 4 are plate-shaped materials to be welded, respectively.

In addition. 5a indicates a contact surface between the welding electrode 1 and the welded material 3, and 5b indicates a contact surface between the welding electrode 2 and the welded material 4.

Next, the operation of the seam welding method according to the above configuration will be explained.

First, when a welding current is applied to the disc-shaped welding electrodes 1 and 2 and the materials to be welded 3 and 4 are rotated while being pressurized, the materials to be welded 3 and 4 are fed out while being welded, so that they are continuously joined. An airtight joint can be obtained.

As this welding speed is increased, the energization time per unit length (the time during which welding current flows) becomes shorter, so the contact surfaces 5a and 5b become extremely hot before the joint surfaces melt. .

And finally it melts. For this reason, welding of the welding electrodes 1 and 2 and the welded materials 3 and 4 occurs, or surface dust occurs immediately after the contact surfaces 5a and 5b.

Generally, as the welding speed increases, a larger welding current is required.

That is, although the current density at the joint surfaces 5a and 5b must be increased, the time during which the welding electrodes 1 and 2 are in contact with the welded materials 3 and 4 is shortened.

Therefore, the welding electrodes 1 and 2 cannot sufficiently cool the materials to be welded 3 and 4.

As described above, in the conventional seam welding method, the welding electrodes 1 and 2 are welded to the surfaces of the materials 3 and 4 to be welded, or dust is generated from the surfaces of the materials 3 and 4 to be welded.

For this reason, the welding speed is restricted and high-speed seam welding cannot be performed.

Moreover, the welding speed must be lowered as the thickness of the plate increases, so it was not possible to increase the welding speed for thick plates.

For example, when the plate thickness is in the order of 3.2, there is a drawback that seam welding of 2 m/mitt or more is difficult.

Therefore, an object of the present invention is to provide a seam welding method that can increase the welding speed of seam welding.

In order to achieve such an object, the present invention provides a protrusion in the longitudinal direction of one of the welded materials on the joint surface of the welded material, and performs welding using a welding electrode wider than the width of this protrusion. will be described in detail below using examples.

FIGS. 2a and 2b are a side view and a front view showing an embodiment of the seam welding method according to the present invention.

In the figure, 6 and 7 are axes 6a and γa, respectively.
Wide disc-shaped welding electrodes 8 and 9 that rotate around the welding surface are welded materials, and in particular, the welding surface of the welded material 8 is provided with projections 8a in its longitudinal direction.

In addition, 10a shows the contact surface of the welding electrode 6 and the material to be welded 8, and 10b shows the contact surface of the welding electrode 7 and the material to be welded 9, respectively.

Next, the operation of the seam welding method according to the above configuration will be explained.

First, when a welding current is applied to the disc-shaped welding electrodes 6 and 7 and the materials to be welded 8 and 9 are rotated while being pressurized, the materials to be welded 8 and 9 are fed out while being welded and are continuously joined.

At this time, since the material to be welded 8 is provided with a continuous protrusion 8a in the longitudinal direction thereof, the welding current is throttled by the protrusion 8a.

Therefore, the current density at the junction surface becomes significantly large as shown in FIG. 2b.

Moreover, the current density at the contact surfaces 10a and 10b of the welding electrodes 6 and T and the materials to be welded 8 and 9, respectively, becomes small because the widths of the tips of the welding electrodes 6 and 7 are wide.

Therefore, the temperature rise on the surfaces of the welded materials 8 and 9 can be suppressed to a low level, so that dust is not generated from the surfaces of the welded materials, and the welding speed can be significantly improved.

Although the cross-sectional shape of the protrusion 8a of the material to be welded 8 is shown as triangular, it is not limited to this, and may be semi-circular as shown in FIG. 3, or extruded with a press as shown in FIG. It goes without saying that the same effect can be obtained with other shapes as well.

As explained in detail above, according to the seam welding method according to the present invention, the current density at the contact surface between the welding electrode and the material to be welded can be lowered, which has the effect of dramatically increasing the welding speed. .

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional seam welding method, FIGS. 2a and 2b are side and front views showing an embodiment of the seam welding method according to the present invention, and FIGS. 3 and 4 are FIG. 7 is a cross-sectional view showing other examples of the shapes of protrusions of the welded materials. 1 and 2... Welding electrode, 3 and 4...
... Material to be welded, 5a and 5b ... Contact surface, 6
and 7... welding electrode, 8 and 9...
- Material to be welded, 8a...Protrusion, 10a and 10
b...Contact surface.

Claims (1)

[Claims] 1. A seam welding method characterized in that a protrusion is provided on the joint surface of one of the welded materials in the longitudinal direction of the welded material, and welding is performed using a welding electrode wider than the width of this protrusion.