JPH0342146B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of welding thin plate members, and more specifically, for example, when joining a roof and a front pillar or a roof and a rear pillar in an automobile body, The plate part is bulged into a predetermined shape by press working, the deformation of the part caused by welding heat during the welding process is kept within the desired range, and then, after welding, a slight The present invention relates to a welding method for thin plate members, which makes it possible to obtain a joint portion with excellent appearance and stable strength by performing finishing processing.

Generally, the appearance of the outer panels of an automobile body, such as the roof, side panels, bonnet, etc., is the most important part of the product, and therefore, they must be aesthetically pleasing. For this reason, extremely careful outer surface treatment is performed, particularly at the welding portions of the outer panels.

Conventionally, welding of outer panel parts such as a roof, a front pillar, and a rear pillar has been carried out by a welding process shown in FIG. 1. That is, a first plate 2 and a second plate 4 to be welded are prepared, and one end of the plate 2 is pressed to form a tip 6 having a bent cross-section. Next, after positioning the second plate 4 on the tip 6, a brazing material 8 is placed on the abutting area and brazing is performed. In this case, since the brazing filler metal 8 melts at a considerably high temperature, welding heat is applied from the outside, and the respective plates 2 and 4 are softened and deformed by the welding heat, and near both ends of the brazing filler metal 8, as shown in the figure. A concave stepped portion 10 is formed on the surface. Therefore, since the presence of the stepped portion 10 spoils the appearance, the stepped portion 10 is hammered out from its inner surface to form a protrusion 12 that protrudes upward from the respective plates 2 and 4 in the figure. Form. Next, the protrusion 12 and the brazing material 8 are ground to form a smooth outer surface.

By the way, in the above-mentioned conventional technique, the protrusion 12 is formed by hammering out the stepped portion 10 with a hammer or the like, which makes the work complicated and requires a skilled technique. That is, since the punching out work is performed manually, the shape after punching out may become non-uniform depending on the level of skill of the worker. As a result, depending on the uneven protrusion state of the protrusions 12, the recesses 13 corresponding to the protrusions 12 become extremely thin after grinding, which tends to cause problems such as a decrease in strength. Furthermore, it is practically extremely difficult to allocate a large number of skilled workers to the punching operation, and in particular, it is virtually impossible to carry out mass production by line production or the like. In addition, when the shape of the product to be welded is complex, for example, it is necessary to drill a hole in the product for inserting a tool for punching out, so the product may be excessively processed. Moreover, the disadvantage is that the work becomes even more complicated.

In addition to such a welding method, a welding method shown in FIG. 2 has been conventionally practiced.

That is, after performing a predetermined press work on one end of the first plate body 2a to form a tip 6a, the tip 6a is placed on the receiving jig 14. The second plate 4a is placed on the tip 6a, and the first plate 2a
A presser jig 16 is brought into contact with the second plate body 4a and the second plate body 4a, respectively. Next, a brazing material 8a is placed near the welded portion of each of the plates 2a and 4a, and brazing is performed.
In the receiving jig 14 and the holding jig 16, for example,
Supply cooling water.

In such a process, the influence of welding heat in the brazing process is reduced and deformation does not occur in each of the plates 2a and 4a. In addition, each plate 2
The brazing filler metal 8a protruding from a and 4a is removed by grinding.

However, although this type of conventional technology can be suitably used for welding flat plates, etc., when the shape of the workpiece to be welded is complex, it is difficult to hold the workpiece from both sides using a holding jig and a receiving jig. It will be extremely difficult. For example, the roof, front pillar, and rear pillar are no exception. Moreover, the work of positioning and fixing the workpiece using the receiving jig and the holding jig requires considerable time and effort, and is particularly disadvantageous in that it is not suitable for mass production.

The present invention has been made to overcome the above-mentioned disadvantages, and focuses on the fact that the welded part of the workpiece becomes soft due to welding heat and deforms vertically downward, and the welded part is press-formed in advance. By forming this welded part to protrude to cope with deformation caused by welding heat, and performing a slight finish grinding after welding, it is possible to obtain a product with excellent appearance and sufficient strength in an extremely simple and short time. It is an object of the present invention to provide a welding method for thin plate members that is not affected by the shape and type of workpieces.

In order to achieve the above object, the present invention applies press working to one end edge of each of two thin plate members to be polymerized, so that when the two thin plate members are polymerized, the respective thin plate members are The first bulge is bulged out so that one end edge has approximately the same height to form a welding part.
a second step of overlapping the respective welding parts and positioning one end of each at a predetermined distance; and a third step of welding the welding parts by introducing a welding material into the spaced apart part. and a fourth step of finishing the melt material so as to form the same plane as the plane of the thin plate member.

Next, preferred embodiments of the method for welding thin plate members according to the present invention will be described in detail with reference to the accompanying drawings.

First, the steps of the method for welding thin plate members according to the present invention will be schematically explained. That is, two predetermined plates are prepared, and the ends of each plate are pressed to form a protrusion of a predetermined shape that projects upward. Next, the protrusions of the respective plates are brought into contact and polymerized, a brazing material is placed on the protrusions, and the brazing material is heated to braze the plates. Furthermore, after this plate is cooled for a predetermined period of time, the brazing material protruding to the outside is removed using a grinder or the like to obtain a smooth outer surface.

First, an example of a molding device for forming one end edge of each plate body 20, 22 into a predetermined shape as described above will be explained with reference to FIGS. 3a and 3b.
In this case, the mold device 24a for bending the plate body 20 includes a lower mold 26a and an upper mold 28a that moves up and down under the driving action of a press machine (not shown). On the other hand, the mold device 24b used for processing the plate body 22 similarly includes a lower mold 26b and an upper mold 28b that moves up and down under the driving action of a press machine (not shown).

In such a configuration, the respective lower molds 26a,
After placing the plates 20 and 22 at predetermined positions on the upper mold 26b, the upper mold 28 is pressed under the driving action of a press machine (not shown).
By displacing a and 28b in the direction of arrow A, the respective plates 20 and 22 are formed into a predetermined shape by the respective mold devices 24a and 24b. That is, plate body 2
0, a protrusion 30b is formed via a slope with respect to a reference surface 30a that is not involved in the press working. An overlapping surface 30c that defines the same plane as the reference surface 30a is formed on the protrusion 30b through a step, and an overlapping slope 30d inclined at a predetermined angle is formed at the other end of the overlapping surface 30c. . On the other hand, in the plate body 22, one end of the reference bottom surface 32a has an overlapping slope 32b that slopes corresponding to the overlapping slope 30d.
is formed, and an overlapping surface 32c is formed at the other end of this overlapping slope 32b. In this case, the respective protrusion amounts are selected in advance so that when the plates 20 and 22 are positioned in contact with each other, the protrusion 30b and the protrusion 32d including the overlapping surface 32c are at the same height. Moreover, the width length of the overlapping surface 32c is the overlapping surface 30c.
The width is selected to be shorter than the length.

Next, the plates 20 and 22 bent as described above are
The process of polymerizing and brazing will be explained with reference to the fourth step.

Therefore, the overlapping surface 32c is placed on the overlapping surface 30c, and the overlapping slopes 32b and 30d are brought into contact with each other. At this time, the protrusions 30b and 32d are at the same height, and the brazing material 36 is placed in the welding area 34 including the protrusions 30b and 32d, respectively. In addition, in advance,
A gap with a predetermined interval is defined between the protrusion 32d and the protrusion 30b (see FIG. 4a). after that,
The brazing material 36 is heated in a conventional manner to braze and secure the plates 20 and 22 together. Note that during brazing, the welding heat for melting the brazing filler metal 36 softens the respective plates 20 and 22, and as a result, the welding area 34 is displaced vertically downward to the position shown in FIG. 4b. leading to. Therefore, by removing the brazing filler metal 36 that protrudes upward from the reference surface 30a using a grinder or the like, the outer surface 3 is smooth and has an excellent appearance.
8 (see Figure 4c). As can be easily understood from this process, the thin plates 20 and 22 are bent downward due to gravity due to the welding heat during brazing. Therefore, since such a situation is almost predicted, in the present invention, in order to reduce the area that will collapse more than necessary due to welding heat, the welding area 34 of each plate body 20, 22 is pressed upward in advance. A predetermined amount of protrusion is formed through the hole. Therefore, even if the wire is bent by the heat during welding, the range of bending is limited to a region where the brazing material has sufficiently spread. As a result, the original shape of the plate remains with a beautiful appearance even without any particular hammering, while the bending portion only extends over a very narrow range. In the end, if the brazing filler metal is finished within this narrow range, a machined surface with excellent appearance and strength can be obtained.

As described above, according to the present invention, the process of hammering out the welding area, which was conventionally extremely complicated and required skill, is omitted, so that the welding work can be performed extremely quickly and easily. Moreover, it is possible to always maintain a constant plate thickness at the welded portion and obtain a product with suitable strength. Therefore, it is an extremely effective means for mass-producing products, and has the effect of easily automating work.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to these embodiments; for example, other welding methods may be used instead of brazing. Of course, various improvements and changes in design are possible without departing from the gist of the present invention.

[Brief explanation of drawings]

Fig. 1 is a process diagram showing an example of a conventional welding method for thin plate members, Fig. 2 is an explanatory drawing showing another example of the conventional welding method, and Figs. 3a and 3b show the method of the present invention. An explanatory diagram of the press processing for
4c to 4c are process diagrams showing a method for welding thin plate members according to the present invention. 2, 2a, 4, 4a...plate body, 6...tip part,
8, 8a...brazing metal, 10...step, 12...protrusion, 14...receiving jig, 16...pressing jig, 2
0, 22... plate body, 24a, 24b... mold device,
30a...Reference surface, 30b...Protrusion, 30c...
...overlapping surface, 30d: overlapping slope, 32a: reference bottom surface, 32b: overlapping slope, 32c: overlapping surface,
32d... protrusion, 34... welding site, 36...
Brazing filler metal, 38...outer surface.

Claims (1)

[Claims] 1 Pressing is performed on one end edge of each of the two thin plate members to be superposed so that when the two thin plate members are superposed, the one end edges of the respective thin plate members have approximately the same height. a first step of forming a welding area by bulging the welding area; a second process of overlapping the respective welding areas and positioning one end edge of each at a predetermined distance; and applying weld metal to the spaced apart area. and a fourth step of finishing the welding material so that it forms the same plane as the plane of the thin plate member. Welding method.