JPH03184685A - Manufacture of closed cross sectional structural body - Google Patents

Abstract

PURPOSE:To reduce manufacturing cost by arranging cut-off parts and cut and stand-up parts at the end parts for weld.joining in both members to be welded and matching them in manufacturing closed cross sectional structural body. CONSTITUTION:In manufacturing the closed cross sectional structural body 5 by weld.joining while corresponding at least two members of side sill outer 6 and side sill inner 9, the cut-off parts 8 are arranged at weld.joining part in one side of member 6 and the cut and stand-up parts 11 are arranged in the other side of the member 9. Under the condition that these cut-off parts 8 are matched with cut and stand-up parts 11, edge parts 7, 10 for weld.joining of both members are superposed and stuck and both members are welded and after welding the cut and stand-up parts are removed. By this method, positioning work becomes unnecessary, and automatization and labor saving can be promoted and the cost down can be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing a closed cross-section structure in which at least two members are welded and joined in correspondence.

<Prior Art> As for a method of manufacturing a closed cross-section structure, a method as shown in FIG. 7 is well known (Japanese Utility Model Publication No. 11109/1983).

In FIG. 7, a side sill l of an automobile is shown as a closed cross-section structure, and both members, one member, the side sill inner 2, and the other member, the side sill outer 3, each have an end portion for welding and joining. Flanges 2a, 3a and 2b, 3b are provided, both flanges 2 a N 3
The side sill l is constructed by welding a, 2b, and 3b while positioning them, and welding and joining them by means such as spot welding using a spot welding gun 4 or seam welding (not shown).

<Problems to be Solved by the Invention> However, in manufacturing the above-mentioned closed cross-section structure, careful consideration is required to accurately align the welding/joining ends of one and the other members. necessary, and in some cases it may be necessary to use a positioning jig,
Furthermore, it is necessary to maintain the position after alignment, which requires a lot of effort before welding and joining. Also,
In the case where the closed section structure is a "side sill" like the one shown in the figure, the flange, which serves as the end for welding and joining, is left standing up on the completed side sill, causing an obstacle when getting on and off the vehicle. Moreover, its thin and protruding shape tends to cause interference with other parts, and in some cases can easily cause damage or deformation.

Means for Solving the Problems> In order to solve the above-mentioned problems, in the method for manufacturing a closed cross-section structure according to the present invention, first, a notch is formed in the welding/joining end of one member, and A cut-out corresponding to this notch is provided in advance on the welding/joining end of the other member, and by matching the notch and the cut-out, the welding/joining end of both members can be overlapped. , and decided to make it close together. Then weld it in that state.
The joining ends are welded together, and after welding, the cut and raised portions are removed to form a closed cross-section structure.

Function> If the notches and raised notches match, accurate positioning of the welding/joining ends of one member and the other member can be easily performed, and at the same time, the welding/joining ends They can be easily overlapped and brought into close contact with each other. and,
If the ends for welding/joining in this state are welded together using, for example, a laser beam or other welding means, good welding is possible.After that, by removing unnecessary cuts and raised parts as necessary, This closed cross-section structure does not cause interference with other parts.

<Embodiments> Hereinafter, preferred embodiments of the present invention will be described based on FIGS. 1 to 6. It should be noted that common parts in each embodiment are indicated by the same reference numerals in the drawings, and redundant explanation will be omitted as much as possible.

First embodiment (see FIGS. 1 to 3) A notch 8 is provided in the welding/joining end 7 of the side sill outer 6, which is one member constituting the side sill 5 as a closed cross-section structure, and The welding/joining end lO of the side sill inner 9, which is a member, is provided with a cut-and-raised part 11 having a position and width corresponding to the above-mentioned notch 8. The depth D of the notch 8, the height Hl of the raised cut 11, and the overhang width W of the front portion 12 of the raised cut 11 are appropriately set according to the design conditions and structural conditions of the side sill 5.

Next, as shown in FIG. 2, the notch 8 and the raised notch 11 are aligned, the welding/joining ends 7 and IO of the side sill outer 6 and side sill inner 9 are overlapped, and the ends protrude from the notch 8. By pulling up the cut and raised parts 11, the parts are brought into close contact with each other. Furthermore, the welding/joining end portion 7 and the IOs are welded together using a laser beam welding machine 13. Finally, the cut and raised portion 11 is removed to form the side sill 5 shown in FIG. 3.

In the figure, 14 indicates a welded portion. Note that the means for bringing the side sill outer 6 and side sill inner 9 into close contact using the cutting and raising 11 is not limited to the method described above, and any method may be used as long as external force is applied in a direction to bring the side sill outer 6 and side sill inner 9 into close contact. . Further, in this embodiment, the lower parts 6b and 9b of the side sill outer 6 and the side sill inner 9, which are both members, are the same as in the conventional case, but of course, the lower parts 6b and 9b are cut and raised 11 as described above. A notch 8 may be provided and welding/joining may be performed as described above.

Second Embodiment (See Figures 4 and 5) In this embodiment,
The cut and raised portion 15 is bent and a bent portion 17 is provided thereto for use as an insertion guide for assembly with a pinching portion 16. The existence of this pinching part 16 naturally enables vertical positioning, and if the notch 8 and the raised cut 15 match, the side sill outer 6 and the side sill inner 18 will naturally come into close contact, and the side sill outer 6 and the side sill inner Without applying any external force to 18, both ends 7 and 19 for welding and joining, which are in a good condition with no gaps, can be welded suitably with the laser beam welder 13. Due to the presence of the warped portion 16, the side sill outer 6 and the side sill inner 18 are directly welded and joined at the end 7.
．． 19 can be easily assembled and inserted into each other, and accordingly, the notch 8 and the raised cut 15 can be easily matched.

Third Embodiment (See Figure 6) In this embodiment, a sloped part 22 for an insertion guide is provided at the tip of the notch 21 of the side sill outer 20, which is one member, so that it can be used for both welding and joining. Assembling and inserting the end portions 23 and 19 and matching the notch 21 and the raised cut L5 are even easier.

Note that this method of manufacturing a closed cross-section structure can be applied as long as there are at least two corresponding members, and both members are each provided with an end for welding/joining, and one member and the other member are It does not necessarily have to be an independent member. The present invention can be fully applied if a single component has two parts similar to the two members described above.

<Effects of the Invention> As described above, according to the method for manufacturing a closed cross-section structure according to the present invention, the notch provided at the welding/joining ends of both members to be welded and the notch can be made to match. This makes positioning possible, eliminating the need for special jigs or positioning work. This is important for automation and labor saving in manufacturing.
This is extremely convenient, makes it possible to shorten manufacturing time, and dramatically promotes dropless cost reduction.

In addition, it is possible to make good welds by bringing the welding/joining ends of both parts into close contact with each other and eliminating gaps, and it is possible to weld only from one side without using a flange as in the past. Instead of spot welding or seam welding, it is possible to perform better welding using laser beam welding or other high-density energy, and it is possible to improve the quality of the closed cross-section structure itself. In addition, this greatly increases the degree of freedom in welding postures and angles, leading to improvements in manufacturing equipment, which of course also promotes manufacturing automation, labor saving, and cost reduction. This dramatically increases the degree of freedom in designing and manufacturing the shape of the closed cross-section structure itself.

Furthermore, since the conventional flange is not required, the welded area is approximately flat, and when using a closed cross-section structure, interference with other parts and equipment is reduced, and the appearance is improved. In particular, when used in the interior of a vehicle, on or near the door, it improves the comfort and ease of getting in and out of the vehicle, and when used on the exterior of the vehicle,
Being substantially flat without a thin protruding flange significantly improves durability against damage and deformation due to interference with other objects.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing one embodiment of a method for manufacturing a side sill, which is a closed cross-section structure according to the present invention, and FIG.
Figure 3 is a perspective view showing the completed state of the side sill with the cut and raised parts removed after welding, and the welded part; Figure 4 is a perspective view of the present invention. Fig. 5 is a perspective view equivalent to Fig. 1 showing another embodiment, Fig. 5 is a perspective view equivalent to Fig. 2 showing welding of both members of the embodiment shown in Fig. 4 combined; 7 is a perspective view of a main part showing still another embodiment of the present invention, and FIG. 7 is a perspective view showing a method of manufacturing a side sill as a conventional closed cross-section structure. 6.20 ・・−・−・・・・Side sill outer (
one member) 9.18 ...-Side sill inner (
other member) 7.10.19.23--...
... End for welding/joining 8.21 ---...---
-----------Notch 11.15--
−−−・・−・−・・−・ Cut and raise 13−・−−
−−−・−−−−−−−1・−・−・・・・・
Laser beam welding machine 16 ・−・・−・・・・・−
・・−・−・・−・ Sandwiched part 7 22 Warped part inclined part

Claims (4)

[Claims] (1) In a method for manufacturing a closed cross-section structure in which at least two members are welded and joined in correspondence, a notch provided at the welding and joining end of one member, and a notch corresponding to this notch, The ends for welding and joining of both members are overlapped and brought into close contact with the cut and raised parts provided at the end for welding and joining of the other member, and the ends for welding and joining of both members are aligned. A method for manufacturing a closed cross-section structure, characterized by welding the two together and removing the cut and raised portion after welding. (2) The closed cross-section structure according to claim (1), wherein the cut-and-raised portion is provided with a pinching portion, and when the notch and the cut-and-raised portion are aligned, both the one and the other members are relatively restrained. Production method. (3) The method for manufacturing a closed cross-section structure according to claim (2), wherein a curved part for an assembly insertion guide is provided at the tip of the pinching part provided in the cut and raised part. (4) The method for manufacturing a closed cross-section structure according to any one of claims (1) to (3), wherein an inclined part for an assembly insertion guide is provided at the tip of the notch.