JP3182654B2 - Spot welding structure of pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe spot welding structure applied to a seat frame of a railway vehicle or an automobile.

[0002]

2. Description of the Related Art Conventionally, in a vehicle seat frame, as shown in FIG. 4, a circular pipe 1 and a plate 2 are integrated by spot welding.

[0003]

However, in the prior art, as shown in FIG. 5, a strain 5 occurs in the pipe 1 due to the pressurization by the upper electrode 3 and the lower electrode 4, and the strain 5 causes the pressing force of the welding portion 6 to be increased. In addition, there is a problem that the welding state becomes unstable easily and the welding state becomes unstable.

Further, as shown in FIG. 6, there is a problem that a local deformation 7 occurs in the pipe 1 due to pressurization by the upper electrode 3 and the lower electrode 4, and the welding state becomes unstable due to a difference in contact resistance. is there.

[0005] That is, there is a problem of instability of the welding state caused by insufficient rigidity of the pipe 1, and the joint structure has low reliability of welding quality. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a spot welding structure for a pipe that stabilizes a welding state and improves reliability of welding quality.

[0006]

In order to achieve the above object, the present invention relates to a pipe which is spot-welded to a plate and has a difference in a pressing direction applied by an upper electrode and a lower electrode.
An integral beams as a reinforcing portion so as to pass to the pipe itself
It is characterized by being provided.

[0007]

With the above construction, a beam as a reinforcing portion is provided in a pressurizing direction on a pipe spot-welded to a plate, so that the rigidity of the pipe is increased and distortion and local deformation during spot welding are eliminated. The reliability of welding quality is improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1 showing the first embodiment, a circular pipe 11 spot-welded to the plate 2 is made of a light alloy extruded material in this embodiment.
A beam 11a is provided as a reinforcement in the pressing direction.

Therefore, in the first embodiment, at the time of spot welding, the rigidity is increased due to the presence of the beam 11a in the pipe 11, and distortion and local deformation do not occur, thereby improving the reliability of welding quality. Can be.

In addition, during spot welding, there is no distortion or local deformation due to pressurization, and since it is close to spot welding, the current value can be reduced and the energy saving effect can be achieved.

Further, since the second moment of area around the aa axis is increased by the beam 11a, the weight can be reduced by reducing the wall thickness at the equivalent second moment of area (see Table 1).

[0012]

[Table 1]

FIG. 2 shows an example of a square pipe 12 as a second embodiment. Also in this embodiment, the beam 12a as a reinforcing portion
However, the same effect as in the first embodiment can be obtained not only for a round pipe but also for a pipe having a rectangular cross section.

FIG. 3 shows a third embodiment.
If the nugget forming part at the time of spot welding is formed into a flat shape (flat part 11b) in the circular pipe 11,
More reliable welding can be performed in a state similar to lap welding.

[0015]

As described above, according to the present invention, in a pipe spot-welded to a plate, a beam as a reinforcing portion is provided in the pressing direction, so that the rigidity is improved and the reliability of welding quality is improved. Can be improved.

In addition, since it is close to spot welding, the current value can be reduced as compared with the prior art, and an energy saving effect can be achieved. In addition, since the secondary moment of area around the horizontal axis is increased by the beam,
Weight reduction can be achieved by reducing the thickness at the equivalent moment of inertia of area.

Further, on the joint surface, not only the number of assembling steps can be reduced but also the degree of freedom in design can be improved as an alternative to riveting.

[Brief description of the drawings]

FIG. 1 is an explanatory front view of a first embodiment according to the present invention.

FIG. 2 is an explanatory front view of a second embodiment according to the present invention.

FIG. 3 is an explanatory front view of a third embodiment according to the present invention.

FIG. 4 is an explanatory front view of a conventional technique.

FIG. 5 is another explanatory front view of the prior art.

FIG. 6 is another front explanatory view of the prior art.

[Explanation of symbols]

 11,12 pipe 11a, 12a beam

Claims (1)

(57) [Claims] In a pipe spot-welded to a plate, a difference in a pressing direction applied by an upper electrode and a lower electrode.
An integral beams as a reinforcing portion so as to pass to the pipe itself
Spot welded structure of the pipe, characterized by comprising Te.