JPH0731889Y2 - Bonding structure between pressed parts and steel pipes - Google Patents

Description

[Detailed Description of the Invention] a. Field of Industrial Application The present invention relates to a joint structure between a pressed part and a steel pipe.

b. Conventional Technology Conventionally, for example, when constructing a frame of an automobile, there is a case where a portion that cannot be formed by a steel pipe in terms of shape is a pressed part, and the frame is constructed by connecting the pressed part and the steel pipe.

The joint structure between the pressed part and the steel pipe in such a case is generally as shown in FIG.

That is, a press-molded product 101,102 consisting of two parts, an upper part and a lower part.
By spot welding flanges 103, 104 formed on both sides of each, to form an integral closed cross-section, the steel pipe 106 is inserted into the opening 105 formed at the end of the steel pipe 106 and the periphery thereof. It was done by arc welding the press part opening 105.

c. Problems to be Solved by the Invention However, in the above-described joining structure of the press part and the steel pipe, since the welding position is only the arc welding portion between the periphery of the steel pipe 106 and the press part opening 105, The joint strength is weak.

In addition, the flanges 103 and 104 existing on both sides of the pressed part
Plays a role of improving rigidity, but since the flanges 103 and 104 are suddenly interrupted in the vicinity of the opening 105, stress concentration occurs at the welding position.

The present invention has been made in view of the problems of the above-described conventional joint structure between a pressed part and a steel pipe.

d. Means for Solving the Problems In order to solve the above-mentioned problems, the present invention inserts a steel pipe into the opening of a press part formed by spot welding two or more press-formed products with their flanges. In the structure of joining by welding, the flange of the pressed part is gradually changed from the width required for spot welding in the vicinity of the opening to the width required for arc welding, and there is a gap between the flanges in the vicinity of the opening. The steel pipe is inserted through the flange-shaped press part opening, the periphery of the steel pipe and the press part opening are arc-welded, and the flanges having the above-mentioned gap and the steel pipe side wall are arc-welded.

e. Operation As described above, the joint structure between the pressed part and the steel pipe according to the present invention arc welds the periphery of the inserted steel pipe and the opening of the pressed part, and the flanges of the pressed parts having a gap and the side wall of the steel pipe are arced. Since they are welded, the joint strength is improved.

In addition, since the flange provided on the pressed part was gradually changed from the width required for spot welding to the width required for arc welding near the opening through which the steel pipe was inserted, there was no sudden change in the section modulus. , Stress concentration is less likely to occur.

f. Embodiment Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Here, FIG. 1 is a perspective view showing a vehicle body 1 of an integral structure having a partial frame 2 in a part thereof.

The partial frame 2 is made of a pressed part for a portion that cannot be formed by a steel pipe in terms of shape, the cross member 3 is made of a steel pipe, and the side member 4 is a pressed part in front of the side member 4, as shown in FIG. The rear part is made of steel pipe 6.

As shown in FIG. 3, the press part 5 has an integrally closed cross section formed by spot-welding press-formed products 5a and 5b consisting of two parts, an upper part and a lower part, with flanges 7 and 8 formed on both sides of each part. Is formed.

An opening 9 through which the steel pipe 6 can be inserted is formed at the rear end of the press part 5, and the flanges 7 and 8 near the opening 9 are used for arc welding from a width (about 15 mm) required for spot welding. The width is gradually changed to a required width (about 5 mm), and is bent so that a gap 10 is formed between the flanges 7 and 8 near the opening 9 as shown in FIG. ing.

In joining the steel pipe 6 to the press part 5 formed as described above, first, the press part 5 is attached to the flange 7,
Spot welding between 8 pieces, then insert the steel pipe 6 into the opening 9 of the press part 5, and as shown in FIG. 5, arc welding the periphery of the steel pipe 6 and the opening 9 of the press part 5,
The flanges 7 and 8 having the gap 10 and the side wall of the steel pipe 6 are arc-welded.

As described above, the joining structure between the pressed part 5 and the steel pipe 6 according to the present invention has a sufficient joining strength because the welding positions are in both the circumferential direction and the longitudinal direction of the steel pipe 6.

Further, since the flanges 7 and 8 provided on the pressed part 5 are gradually narrowed in the vicinity of the opening 9 which is the joint portion with the steel pipe 6, the section modulus abruptly changes even after the steel pipe 6 is joined. There is no stress, and stress concentration is less likely to occur at the joint.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications and changes can be made based on the technical idea of the present invention.

For example, in the above-mentioned embodiment, the joint structure of the press part 5 and the steel pipe 6 constituting the frame 2 of the vehicle body 1 has been described, but the present invention is not limited to this, and the present invention can be used for joining various press parts and steel pipes. It is possible.

Further, the press parts are not limited to the press-formed products 5a and 5b consisting of the upper and lower two parts, and the left and right two-parts or the press-formed parts composed of three or more parts are provided on both sides of each. The formed flanges may be spot-welded to each other to form an integral closed cross section.

Further, the steel pipes to be joined are not limited to square pipes, and can be used in various steel pipes such as circular pipes and elliptic pipes.

g. Effect of the Invention According to the joining structure of the press part and the steel pipe according to the present invention,
The structure has high bonding strength and stress concentration is less likely to occur at the bonding portion.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention. FIG. 1 is a perspective view showing a vehicle body structure, and FIG.
It is a principal part expansion perspective view of a figure. FIG. 3 is an exploded perspective view of the X portion of FIG. 2, and FIG. 4 is a perspective view of the X portion of FIG. 2 before welding. FIG. 5 is a perspective view of the portion X in FIG. 2 after welding. FIG. 6 is a perspective view of a portion corresponding to the portion X in FIG. 2 showing the conventional joint structure between a pressed part and a steel pipe. 5 ... Pressed parts, 6 ... Steel pipes, 7,8 ... Flanges, 9
…… Aperture, 10 …… Gap.

Claims (1)

[Scope of utility model registration request] Claim: What is claimed is: 1. In a structure in which two or more press-molded products are spot-welded together at their flanges, and a steel pipe is inserted into and joined to the opening of the press-formed product, the flange of the pressed product is provided near the opening. In gradual change from the width required for spot welding to the width required for arc welding, a gap is provided between the flanges near the opening, and a steel pipe is inserted into the flange-shaped press part opening, A joint structure between a pressed part and a steel pipe, characterized in that the periphery of the steel pipe and the opening of the pressed part are arc-welded, and the flanges having the above gap and the side wall of the steel pipe are arc-welded.