JP3148125B2 - Joint structure between members - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure between metallic members such as aluminum which can be employed in various structures such as a frame structure of a space frame of an automobile and a frame structure of a building structure.

[0002] In this specification, the term "aluminum" is used to include its alloys.

[0003]

2. Description of the Related Art For example, a space frame of an automobile is
A large number of metal wrought materials are joined together, and joining has been performed by arc welding such as MIG or TIG, or mechanical fastening such as bolting.

[0004]

However, in the above-described joining structure by arc welding, the strength of the weld heat affected zone is reduced, so that the strength of the entire joining structure material is determined and the degree of freedom in design is reduced. There was a drawback of lowering. In addition, when the member is made of, for example, aluminum, there is a limit to the range of alloys that can be arc welded,
It is difficult to adopt aluminum alloys such as A6000 series and A2000 series, and there is a drawback that the degree of freedom of design is limited from this aspect as well. Further, there is also a disadvantage that stress concentration tends to occur at the toe, and therefore, it is weak against fatigue. Also,
Welds may have weld defects such as cracks and blowholes, and there has been a complication in the quality of the joints. Particularly, in the case of an aluminum alloy containing the elements of Mg and Zn, there is also a disadvantage that these elements evaporate in the welded portion during welding. Further, in the case of arc welding, a weld bead is generated, and when it is necessary to remove the bead,
There is also a drawback that finishing work for the removal is troublesome. Furthermore, in the case of arc welding, a large distortion occurs,
There was also a problem that much labor was required for straightening after welding, and it was not possible to manufacture a joined product with high productivity.

[0005] In a joining structure by mechanical fastening,
In the case of bolting, it is necessary to make a bolt hole, stress concentration tends to occur there, and there is a troublesome problem in that design considerations are required.

Further, since the wrought materials are joined to each other, there is a limit in the degree of freedom in the joining direction of the other member to one member, and the members are joined in a desired direction in design. There was also the disadvantage of having limitations.

The present invention has been made in view of the above-mentioned conventional problems, and can realize a joint having excellent strength and reliability, and can form a joint having good quality without defects. , And can be manufactured with good productivity.
An object of the present invention is to provide a joint structure between members that can increase the degree of freedom in the joining direction between members.

[0008]

The object of the present invention is to provide a wrought aluminum member having one member and an aluminum member having the other member.
And a fitting portion for fitting the other member to at least one of these members,
The two members are combined in a fitting state in the fitting portion, and the members are connected to each other outside the outer member in the fitting portion.
The friction welding method of softening and joining by the frictional heat given by the probe arranged on the side is solved by the joining structure of members characterized by being integrally joined in the circumferential direction at the fitting portion. You.

That is, in the present joining structure, the aluminum members are joined and integrated at the fitting portion by a friction welding method without melting the joining portion.
In addition to eliminating the problem of strength reduction due to thermal effects such as in the case of arc welding where the joint is melted, members of materials that are difficult to arc weld can be joined, and the material range of the members is expanded,
Further, the problem of stress concentration due to drilling in the case of mechanical fastening is also eliminated, so that a joint having excellent strength and reliability can be obtained while increasing the degree of freedom in designing the base material of the member.

In addition, problems such as the occurrence of welding defects and the problem of stress concentration at the toe at the time of arc welding are eliminated, and from this aspect, a joint having excellent strength, reliability and quality can be realized. You.

Further, no bead is generated as in the case of arc welding, troublesome finishing work for removing the bead is eliminated, and troublesome straightening correction as in the case of arc welding is not required. Thereby, a joined structure can be obtained with high productivity.

Further, according to the present invention, the members are connected to each other at the fitting portion.
Probe located outside the outer member
In the joining structure by the friction welding method that softens and joins with the applied frictional heat, one of the members is made of a wrought material and the other is made of a cast material with a large degree of freedom in shape design. One member made of the drawn material is joined to the other member made of the cast material with a high degree of freedom in the direction, and has a directionality that was difficult or impossible to achieve with the conventional joining of the wrought materials. Joining is very easily achieved.

[0013]

Next, an embodiment of the present invention will be described.

The joint structure between metal members according to the present embodiment is employed in a space frame structure of an automobile. However, the joint structure according to the present invention is not limited to this. Needless to say, it can be widely used in various structures.

In the joint structure of the members shown in FIG. 1A, (1) is an extruded aluminum material as a wrought material, and (2) is an aluminum die-cast material as a casting material. The members (1) and (2) may be made of an A6000-based or A2000-based aluminum alloy, which is considered difficult to weld. Fig. 1 (a)
As shown in (b), the die casting material (2) is provided with a plurality of protrusions (2b)... In a body direction (2a) thereof in predetermined directions, and each of the protrusions (2b). Is provided with a fitting insertion hole (2c) having a predetermined depth to fit the end of the extruded mold (1)... The end of each extruded die (1) is inserted and fitted in the insertion hole (2c)... Of the die cast material (2). And are combined in a fit without play.

The joining portion (3) between the extruded mold members (1) and the die casting material (2) is formed by a friction welding method in which the fitting portions are heated and softened by frictional heat and joined. . This friction welding method is a kind of solid-phase joining method in which joining is performed without melting a joining portion, and softening is performed by giving frictional heat to a contact portion between members (1) and (2) in a fitting portion or a portion in the vicinity thereof. Then, if necessary, the portions are joined by pressing.

[0017] In Thus, it is on the occasion on the application of friction welding method, the following
Such a method is practical. That is, FIG.
As shown in (1), a friction heat applying member such as a shaft (4) rotated at a high speed is connected to a member (1) in a fitting portion.
(2) The contact portion between the members (1) and (2) or the vicinity thereof is softened by the frictional heat generated by bringing the member into contact with the boundary portion or the region near the boundary portion under a predetermined pressure. It is a joining method. When the high-speed rotating shaft (4) is used in this way, for example, as shown in the drawing, the high-speed rotating shaft (4) is brought into contact with the outer peripheral portion of the projection (2a) of the die-cast material (2) while rotating at high speed. This can be performed by moving the shaft (4) around the entire circumference of the protrusion (2a).

In this friction welding, the member (1)
(2) The pressure is applied when the contact portions of the members are pressed against each other by pressing the high-speed rotating shaft (4) against the member (2) as described above, or by pressing the member (1).
It may be performed by separately applying an external force to (2).

In the joint structure of the members according to the above embodiment, the main body (2a) is provided with the projection (2b) oriented in a predetermined direction, and the projection (2b) is fitted to the projection (2b) at a predetermined depth. A die-casting material (2) provided with an insertion hole (2c) is provided as a constituent member, and a protrusion (2b) of the die-casting material (2) is inserted into a fitting insertion hole (2c). The ends are properly inserted and fitted into an appropriate state, and the die casting material (2) and the extruded mold material (1) are joined and integrated by a friction welding method in which they are softened and joined by frictional heat at their fitting portions. Because of the degree of freedom in designing the die casting material, one member (1) has a large degree of freedom in the direction with respect to the other member (2), and is appropriately joined in a desired direction. can do.

In particular, as described above, the die casting material (2)
Is used as an intermediate joint member for connecting a plurality of extruded members (1), a plurality of protrusions (2b) are projected in a desired direction, and each protrusion (2b) )
The intermediate joint member (2) having a complicated shape in which a fitting insertion hole (2c) is provided can be easily formed by die-casting, and each extruded material (1) is formed into a die-cast material (2). On the other hand, it is possible to extremely easily realize appropriate joint portions joined in various desired directions.

Although one embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications are possible. For example, the number of extruded members (1) joined to the die-cast member (2) is not limited, and may be one. The extruded member (1) to the die-cast member (2) may be used.
Can be designed in various directions by adopting various shapes that can be die-casted into the die-casting material (2), and there is no particular limitation. Extruded material (1)
In addition to the circular cross-sectional shape, the cross-sectional shape may be a modified cross-section other than a circular shape, and the cross-sectional shape of the insertion hole portion (2c) of the die-cast material (2) may be a cross-sectional shape corresponding thereto. In the above embodiment, the die casting material (2) is provided with a fitting insertion hole (2c) for inserting the end of the extruded material (1). So that
A die casting material (2) having an insertion projection (2d) formed by die casting is prepared, and the insertion projection (2d) is inserted and fitted to the end of the hollow extruded material (1) in a suitable state. A joining structure in which the two members (1) and (2) are joined and integrated (3) by a friction welding method based on frictional heat softening may be used. In the above embodiment, one member (1) is an extruded material and the other member (2) is a die-cast material. The extruded material is an example of a wrought material, and the die-cast material is an example of a casting material. However, other wrought materials and other cast materials may be employed. In the above embodiment, the members (1) and (2) are made of an aluminum material.
(2) may be made of various metal materials including other iron-based materials.

[0022]

As described above, according to the joint structure of the members of the present invention, the aluminum members are connected to each other at the outside of the fitting portion.
Granted by a probe located outside of the side member
The structure is integrated by joining in the circumferential direction by the friction welding method of softening and joining by the frictional heat, so the problem of strength reduction due to heat influence as in the case of arc welding of MIG, TIG etc. Is resolved, and the range of material for the members is expanded,
Furthermore, the problem of stress concentration due to drilling in the case of mechanical fastening is also eliminated, and therefore, a joint having excellent strength and reliability can be realized, and the degree of freedom in design of the structure and the applicable range are expanded. be able to. In addition, problems such as the occurrence of welding defects and the problem of stress concentration at the toe portion in the case of arc welding are eliminated, and from this aspect, it is possible to realize a joint having excellent strength reliability and quality. . Furthermore, a bead that is not generated as in the case of arc welding is eliminated, troublesome finishing work for removing the bead is eliminated, and troublesome straightening is not required. Can be.

According to the present invention, in the joining structure by the friction welding method, one of the members is made of a wrought material and the other is made of a cast material having a large degree of freedom in shape design. One member can be joined to the other member of the cast material in a free direction with high degree of freedom in the direction, and it has been difficult or impossible to achieve with the conventional joint structure between wrought materials. Directional bonding can be realized very easily.

[Brief description of the drawings]

FIGS. 1A and 1B show a joint structure between members according to an embodiment. FIG. 1A is a perspective view, and FIG. 1B is a perspective view showing members in a separated state.

FIGS. 2A and 2B show a joining method of the joining portion. FIG. 2A is a sectional view, and FIG. 2B is a sectional view taken along line II-II in FIG.

FIGS. 3A and 3B show a joining portion of a joining structure according to another embodiment, in which FIG. 3A is a cross-sectional view, and FIG.
FIG. 3 is a sectional view taken along line III.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Extruded material (extended material) 2 ... Die-cast material (cast material) 2c ... Insertion hole part for fitting 3 ... Joint part

Continuation of the front page (56) References JP-A-5-23874 (JP, A) JP-A-9-122936 (JP, A) Tables JP-A-7-505090 (JP, A) (58) Fields studied (Int .Cl. ⁷ , DB name) B23K 20/12

Claims (1)

(57) [Claims] 1. One of the members is made of an aluminum wrought material and the other is made of an aluminum casting material, and a fitting portion is provided for fitting at least one of the members to the other member. , together with the two members are combined in a fitting state at the fitting portion, the member with each other, the fitting
Probe located outside the outer member of the
And a friction welding method of softening and joining by the applied frictional heat, and is joined and integrated in a circumferential direction at the fitting portion.