JP2002178189A - Weld joint structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To freely adopt laser welding by narrowing a gap in fitting parts between both extruded shapes to be welded. SOLUTION: Both extruded shapes 1, 2 can be jointed by welding the two fitting parts 10, 11 of the extruded shapes 1, 2 that are made of aluminum or the like as separate bodies. When the part 10 of the two fitting parts is welded, the welding distortion of welded part serves to narrow the gap between both extruded shapes at the recessed/projected engaged part 11 of the other fitting part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welded joint structure, and more particularly to a welded joint structure capable of suitably welding extruded members of aluminum and aluminum alloy by high energy beam welding.

[0002]

2. Description of the Related Art High energy beam welding, particularly laser welding, enables the welding of relatively thick aluminum parts due to the development of a high energy output device and its control device, and an automatic welding technology utilizing a welding robot or the like. In conjunction with the use of, it has begun to be incorporated into the mass production process of components in the construction and automotive industries. Aluminum and aluminum alloys have obtained great advantages by using laser welding, such as improving the working environment and greatly reducing welding distortion.

[0003]

On the other hand, in order to obtain a high quality laser welded joint, conventional arc welding (MI
G, TIG, etc.), assembling accuracy of the joint before welding,
It is necessary to keep the position accuracy at a high level. This is a factor that hinders widespread use of laser welding, for example, by limiting the shape of the material to be welded or increasing the cost of preparing joints.

For example, a 2 mm thick aluminum plate 2
When lap welding or lap fillet welding is performed by partially overlapping the sheets, the latest arc welding technology can weld even if the gap between the two sheets is about 2 mm, which is comparable to the thickness of the sheet itself. . On the other hand, in the lap laser welding of the same material to be welded, the gap between the plates is required to be within 0.1 mm, and at most 0.3 mm. In lap fillet welding, of course, unless the plate surface at the lap position is assembled with high precision, it is not possible to irradiate the laser beam to the accurate fillet position in automatic welding by a robot etc. .

The present invention has been made in view of the above circumstances, and has as its object to narrow the gap between the fitting portions between both members to be welded and to freely employ laser welding. It is an object of the present invention to provide a welded joint structure.

[0006]

To explain the background of the invention, an extruded member made of aluminum or the like has a relatively free and inexpensive thickness distribution fluctuating due to a complicated cross-sectional shape or cross-sectional portion. It can be realized and widely used in various industries. When extruded sections made of aluminum or the like are used in combination, one extruded section is provided with a fillet projecting outward, and the other section is provided with a groove for receiving the fillet. In some cases, so-called fitting, which makes it easy to determine the combination position of extruded members, is often used by devising such a combination portion at two or more places.

When the fillet and the groove are combined, it is possible to make use of a slight elastic deformation to make it difficult for the combined shape to come off. If the fitting portion including the fillet and the groove is used in the welded joint structure, the positional relationship between the materials to be welded is defined, and the assembly before welding is facilitated. The fitting portion here is not limited to a mere fitting portion, but is used in a broad sense defined as, for example, a cross-sectional portion provided to assist positioning between the two members. here,
The inventors of the present application have conducted intensive studies, and as a result, when there are a plurality of fitting portions of both extruded profiles made of aluminum or the like which is a welding portion, by devising the shape and position of these fitting portions, Also, by using the uneven fitting part,
The welding strain of the previously welded fitting portion can be set so as to narrow the gap between both extruded members of the next fitting portion to be welded, and a high quality welded joint structure can be obtained. This led to the present invention.

That is, in the invention according to the first aspect, in the welded joint structure connecting the two members by welding at least two fitting portions of the two members separated from each other, When one fitting portion of the fitting portions is welded, the welding strain of the welded portion reduces the space between the two members of the other fitting portion so that It is characterized in that the shapes and positions of at least two fitting portions are set respectively.

In the present invention, one of the at least two fitting portions is welded, and the welding strain reduces the distance between the two members of the other fitting portion. Since the narrow fitting portion is to be welded, for the other fitting portion, even if the gap between the fitting portions of the two members is too large before welding and the laser welding cannot be performed, the one fitting portion is used. Is welded, the gap between the two members of the other fitting portion can be reduced by welding strain at this time, so that the possibility of introducing laser welding increases.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention.
Is shown. Aluminum alloy JIS
An extruded profile 1 made of A6NO1 alloy and an extruded profile 2 made of the same aluminum alloy JIS A6NO1 alloy are welded at their two fitting portions 10 and 11 to form the two extruded profiles 1 and 2 respectively. It is an example of the welded joint structure connected.

The extruded profile 1 is substantially a square tube,
A fillet 3 protruding outward is provided at the lower side of a so that the bottom portion 1b extends. The extruded profile 2 is also a substantially square tube larger than the extruded profile 1 and has an upper surface 2
A fillet 4 protruding upward is provided on one side 2b side of a so that the one side 2b extends. Although the fillet 4 is formed to be slightly inclined outward in FIG. 1, the fillet 4 does not necessarily need to be inclined and may be kept straight. On the other side 2c side of the upper surface portion 2a of the extruded profile 2, a hook-shaped fillet 5 having an L-shaped cross section and a tip bent at a right angle is formed. A groove 6 into which the fillet 3 of the extruded profile 1 is inserted is formed between the hook-shaped fillet 5 and the upper surface 2a of the extruded profile 2.

The fillet 4 of the extruded profile 2 and the side face 1c of the extruded profile 1 facing the fillet 4 constitute a fitting portion 10.
Further, the hook-shaped fillet 5 of the extruded profile 2 and the fillet 3 of the extruded profile 1 together form a fitting portion 11 which fits in a concave and convex manner.

Here, the relationship between the two fitting portions 10 and 11 is such that one of the two fitting portions has a fitting portion 1.
When 0 is welded, the gap between the two extruded sections of the other fitting portion 11, that is, the gap L between the hook-shaped fillet 5 and the fillet 3 is reduced by the welding strain of the welded portion. The shapes and positions of the two fitting portions 10 and 11 are set respectively.

Next, a description will be given of a method of welding the two extruded sections having the above-described welded joint structure. First, the extruded profile 1 is placed on the upper side of the extruded profile 2, and the corner formed by the bottom surface 1 b and the side surface 1 c of the extruded profile 1 is aligned with the root of the fillet 4 of the extruded profile 2. To the hook-shaped fillet 5 of the extruded profile 2, and in this state,
The extruded profiles are shifted in the axial direction, and both extruded profiles 1 and 2 are set as shown in FIG.

Next, when the fitting portion 10 is overlap-welded by laser welding, the extruded profile 1
Is rotationally displaced relative to the extruded profile 2 in the direction of the arrow (a) in the figure. Therefore, in the fitting portion 11 which is a fitting portion between the fillet 3 and the hook-shaped fillet 5, the fillet 3 of the extruded profile 1 is provided on the extruded profile 2 so as to move away from the upper surface 2 a of the extruded profile 2. It is pressed against the lower surface of the hook-shaped fillet 5. That is, the distance L between the fillet 3 and the hook-shaped fillet 5 is reduced and approaches zero. As a result,
High quality of the next lap welding portion using the laser of the fitting portion 11 can be achieved.

In the above-described embodiment, the fillet 4 is inclined outward, but the fillet 4 may be erected in the vertical direction, and the side surface 1c of the extruded profile 1 may be inclined inward instead. . Further, the lower surface of the hook-shaped fillet 5 provided on the extruded section 2 may be inclined.

<Second Embodiment> FIG. 2 shows a second embodiment of the present invention. In this embodiment, a substantially cylindrical extruded shape member 20 made of an aluminum alloy JIS A6NO1 alloy is used.
A bracket 21 obtained by cutting out an extruded shape member made of NO1 into a short length is welded to the two fitting portions 22 and 23 so that the two extruded portions 20 and 2 are welded.
1 is an example of a welded joint structure where 1 is connected.

The extruded section 20 has a substantially circular cross section,
A hook-shaped fillet 24 having an L-shaped cross section is provided on the outer periphery. A groove 27 into which a second leg 26 described later is inserted is formed between the hook-shaped fillet 24 and the arc-shaped outer peripheral portion of the extruded profile body. The bracket 21
Is formed in a substantially A-shaped cross section attached to the outer periphery of the extruded profile 20 having a circular cross section, and is formed as a cross section of an extruded profile of an aluminum alloy. At the base end of the bracket 21, first and second legs 25 and 26 are formed, each of which extends outwardly and is curved at a curvature substantially equal to the curvature of the extruded profile 20. .

The first leg portion 25 of the bracket 21 and the corresponding predetermined portion 20a of the outer peripheral portion of the extruded profile 20 constitute a fitting portion 22. Also, the second leg 26 of the bracket and the hook-shaped fillet 24 of the extruded profile 20 together form a fitting portion 23 that fits in a concave and convex manner.

Here, the relationship between the two fitting portions 22 and 23 is such that one of the two fitting portions has a fitting portion 2.
2 are welded, the distance between the two extruded sections of the other fitting portion 23, that is, the distance M between the second leg 26 and the hook-shaped fillet 24 is caused by the welding strain of the welded portion. So that the positions and shapes of the two fitting portions 22 and 23 (particularly, the brackets 21 forming the fitting portions,
Of the first leg 25 and the outer peripheral portion 20 of the extruded profile 20
a are both formed to have substantially the same curvature).

The method of welding the two extruded members having the above-described welded joint structure will be described.
1 to the hook-shaped fillet 2 of the extruded profile 20.
4 (fitting portion 23), and the first leg 25 of the bracket is attached to a predetermined portion 20 of the outer peripheral portion of the extruded profile 20.
(a fitting part 22).

Next, when the fitting portion 22 is overlap-welded by laser welding, the heat-shrinkage of the welding bead B causes the arc-shaped convex curved portion outside the first leg portion 25 to be distorted so as to have a large radius of curvature. Accordingly, the entire bracket 21 is deformed so as to have a curvature as shown by an arrow (b) with respect to the extruded profile 20. As a result, in the fitting portion 23, the second leg 26 of the bracket 21 is 21 is pressed against the inner surface of a hook-shaped fillet 24 provided on the same. That is, the interval M between the second leg 26 and the hook-shaped fillet 24 is reduced and approaches zero. As a result, high quality of the next lap welding portion using the laser of the fitting portion 23 can be achieved.

In each of the above-described embodiments, the extruded shape of the aluminum alloy is exemplified by a round shape or a square shape. However, the present invention is not limited to this. The present invention can be applied to a T-shaped or chevron-shaped extruded member. In addition, in order to obtain the joint structure for welding of the present invention, it is industrially inexpensive to use a cross section of an extruded shape and suitable for mass production, but one or both of the joints is formed by casting, die casting, casting, or the like. It is also possible to use molded extruded profiles. The present invention is also applicable to a case where an extruded member made of magnesium and its alloy is used in addition to aluminum. Furthermore, in each of the above-described embodiments, laser welding of two fitting portions has been described. However, the present invention is not limited thereto, and the present invention is applicable to a case where three or more fitting portions are laser-welded. It goes without saying that is applicable.

[0025]

According to the present invention, at least one of the two fitting portions is welded, and the welding strain at this time reduces the distance between the two members of the other fitting portion. Then, because the gap is to weld the narrowed fitting portion, for the other fitting portion, even if the gap between the fitting portions of the two members is too wide before welding, laser welding,
After welding the one fitting portion, the gap between the two members of the other fitting portion can be narrowed by welding strain at this time, so that the possibility of introducing laser welding increases.
As a result, when laser welding is employed, it is not necessary to maintain the assembly accuracy and positional accuracy before welding at a very high level, and a significant cost reduction can be achieved. In addition, welding joints suitable for high-energy beam welding such as laser welding are provided, contributing to the improvement in productivity and quality of extruded profiles used in the automobile and construction industries, especially extruded profiles such as aluminum. However, it is big. In addition, even if one fitting portion is arranged in such a manner that the fitting surfaces of both members are each curved in an arc-shaped cross section, and the other fitting portion is fitted with unevenness, the introduction of laser welding is further improved. This has the effect of facilitating the operation.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a welded joint structure according to the present invention.

FIG. 2 is a perspective view showing a second embodiment of the welded joint structure according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 extruded section 2 extruded section 3 fillet 4 fillet 5 hook-shaped fillet 10 fitting section 11 fitting section 20 extruded section 21 bracket (extruded section) 22 fitting section 23 fitting section 24 hook-shaped fillet 25 first Leg 26 second leg

Continuation of the front page (72) Inventor Shoji Takeuchi 194 Chifuku, Susono-shi, Shizuoka Prefecture F-term in the Mitsubishi Aluminum Co., Ltd. Chifuku factory (reference) 4E068 BA00 CA14 DB04

Claims (1)

[Claims] 1. A welded joint structure for connecting at least two fitting portions of two separate members by welding the two members, wherein one of the at least two fitting portions is provided. When the fitting portion is welded, the welding strain of the welded portion reduces the distance between the two members of the other fitting portion so that the distance between the at least two fitting portions of the two members is reduced. A welded joint structure wherein the shape and the position are set respectively.