JP3186581B2 - Joint structure between metal 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
Although many metal members are joined together,
This 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,
The weld may have weld defects such as cracks and blowholes, and there has been a problem in terms of the quality of the joint. 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.

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 high-quality joint without defects. Another object of the present invention is to provide a joint structure between members having a structure excellent in productivity.

[0007]

SUMMARY OF THE INVENTION The above-mentioned object is achieved in a longitudinal direction.
Metal members to each other consisting of a hollow member or a solid member of the notches provided with aluminum fitting between part, the cut
To each other can so as to be opposed, the angle of the mutually 30
The metal members are joined together by a friction welding method in which the metal members are softened and joined by frictional heat using a rotary shaft while being joined together at a crossing angle of ~ 150 ° and without play. The problem is solved by a metal structure for joining metal members.

That is, in the present joining structure, since the metal members are joined and integrated at the fitting portion by a friction welding method without melting the joining portion, the arc welding in which the joining portion melts is performed. In addition to eliminating the problem of strength reduction due to thermal effects as in the case, it is also possible to join members made of a material difficult to arc welding, and the material range of the members is expanded,
The problem of stress concentration due to drilling in the case of mechanical fastening is also eliminated, so that a joint with excellent strength reliability can be obtained.

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 a joint having excellent strength and reliability and quality is realized from this aspect. You.

[0010] Further, since 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.

[0011] Then, the present invention provides a joint structure by friction welding method for joining soften using frictional heat, it length
Metal members to each other consisting of a hollow member or a solid member of the notches provided with aluminum fitting the direction intermediate portion, the
The notches each other so as to be opposed, the angle of the cross are combined in the fitting state without looseness in a cross state of 30 to 150 °, at its combination state, the metallic members to each other is their fitting Since the parts are joined and integrated, the positioning of the members at the time of joining is easy, and the joining area between the members is ensured to be wide, so that a joined part excellent in strength is formed.

[0012]

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.

The joint structure shown in FIG. 1A is a structure in which the members (1) and (2) are arranged in a cross shape and joined at the intersection. Each member (1)
(2) is made of a hollow aluminum extruded die, and after being subjected to a predetermined heat treatment, as shown in FIG. 1 (b), intermediate parts in the longitudinal direction of each member (1) (2). Are provided with U-shaped notches (1a) and (2a) for fitting, and these notched concave portions (1a) and (2a) are fitted so that they face each other. By this fitting, the members (1) and (2) mutually affect each other, and an appropriate temporary assembly state without rattling can be obtained. As the members (1) and (2), A6000 series, which is considered difficult to weld,
An aluminum alloy of A2000 series or the like may be used.

In the above structure, the joining portion (3) is formed by a friction welding method in which a fitting portion between the members (1) and (2) is 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 frictional heat is applied to a contact portion between members (1) and (2) in a fitting portion or a portion in the vicinity thereof so that necessary heat is applied. And pressurizing the portion in accordance with the above.

Since the members (1) and (2) cannot be made to rub each other structurally as in a normal friction welding method, for example, as shown in FIGS. Then, a friction heat applying member such as a high-speed rotating shaft (4) is brought into contact with a boundary portion between the members (1) and (2) or a region near the boundary portion in the fitting portion under a predetermined pressure. A method of heating and softening the contact portion between the members (1) and (2) or the vicinity thereof by the frictional heat generated thereby is adopted. This high-speed rotating shaft (4) is shown in FIG.
As shown in (b), the members may be moved along the boundary between the members (1) and (2), or they may be joined according to the location to be joined or the size of the high-speed rotating shaft (4). You may make it hold | maintain in a neutral position. By using such a frictional heat applying operation body, it is possible to easily join even a place where welding by TIG, MIG or the like is difficult.

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

The member (1) formed as described above
(2) In the joint structure between two members, the peripheral wall portion of the other member (2) is disposed in the shape of a partition wall in the fitting notch (1a) of the one member (1), and this is the member (1) ( 2) It also has the effect of strengthening the joints between the members, and the joint strength can be further increased.

FIG. 3A shows a joint structure according to a reference example , in which members (1) and (2) are arranged in a T-shape and joined to each other. Each of the members (1) and (2) is also made of a hollow aluminum extruded die, and is shown in FIG.
As shown in (b), one member (1) is provided with a U-shaped fitting notch (1a) at an intermediate portion in the longitudinal direction, and the other member (2) has the same length. An L-shaped fitting notch (2a) opened outward is provided at one end in the vertical direction, and these notches (1a) and (2a) are opposed to each other so as to be in a fitted state without play. Be combined.

In the joining structure shown in FIG. 3, as shown in FIG. 4, a friction heat applying member such as a shaft (4) rotated at a high speed is connected to the boundary between the members (1) and (2) at the fitting portion. Or by contacting the area near the boundary area under a predetermined pressure, and softening the contact area between the members (1) and (2) or the area near the area by the frictional heat generated thereby.
The joint (3) has been formed.

FIGS. 5A and 5B show still another embodiment . FIG. 5 (a) as another embodiment is one in which members (1) and (2) are notched and fitted in a fitted state without play so that they are in a non-orthogonal crossing state, FIG. 5 (b) as a reference example shows that the end of one member (2) is notched at a predetermined angle in a non-orthogonal state to the middle part in the longitudinal direction of the other member (1). It has been joined. Here, the angle a between the members (1) and (2) is
Can be freely designed in a wide range of 30 to 150 °, and in any case, an appropriate joining state can be realized by a friction welding method.

Although the embodiment of the present invention has been described above, the present invention is not limited to this, and various modifications can be made. For example, the members (1) and (2) may be solid materials in addition to the hollow materials as in the above embodiment. The cross-sectional shape is not limited to the rectangular shape as in the above-described embodiment, but may be various shapes including an irregular shape. Further, both members (1) and (2) may be different from each other in size and shape . Also,
The members (1) and (2) are not limited to extruded materials,
Other various wrought materials may be used. Further, it may be configured as a joining structure when joining the ends of the members.

[0023]

As described above, the joining structure of the members according to the present invention is a structure in which aluminum metallic members are joined and integrated by a friction welding method of softening and joining by using frictional heat. As a result, the problem of strength reduction due to thermal effects as in the case of arc welding is eliminated, the range of material of the members is expanded, and the problem of stress concentration due to drilling in the case of mechanical fastening is also eliminated. Therefore, it is possible to realize a joint having excellent strength reliability, and it is possible to expand the degree of freedom of design of the structure and the applicable range. 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 a joining structure by a friction welding method , a notch for fitting is provided at an intermediate portion in a longitudinal direction.
Are metallic members to each other consisting of aluminum hollow member or a solid material, so as to face with each other said notch
Te, the angle of the cross are combined in the fitting state without looseness in a cross state of 30 to 150 °, at its combination state, the metallic members to each other is integrally joined at their fitting portion structure Therefore, a large joint area between the members can be ensured, and a very strong joint can be formed. In addition, positioning of the members at the time of joining can be easily realized, and a joint structure excellent in accuracy can be easily realized.

[Brief description of the drawings]

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

FIGS. 2A and 2B show a joining method in the joining structure of FIG. 1; FIG. 2A is a plan view of a joining portion, and FIG.
FIG. 2 is a sectional view taken along line II-II.

FIGS. 3A and 3B show a joint structure between members according to a reference example , wherein FIG. 3A is a perspective view, and FIG. 3B is a perspective view showing the members in a separated state.

4A and 4B show a joining method in the joining structure of FIG. 3 ; FIG. 4A is a front view as viewed from the front in the butting direction of FIG. 3A; FIG. It is a line sectional view.

FIG. 5 (a) shows another embodiment, and (b) shows another embodiment .
It is a top view which shows the joining structure of the members which concerns on a reference example, respectively .

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... One member 1a ... Notch for fitting 2 ... The other member 2a ... Notch for fitting 3 ... Joining part 4 ... High-speed rotation shaft

Continuation of the front page (56) References JP-A-1-284442 (JP, A) JP-A-52-123358 (JP, A) WO 93/10935 (WO, A1) WO 95/26254 (WO, A1) J.). F. Hinrichs and 3 others, "Challenges of Welding Aluminum Alloys for Automatic Structures", Svetsa ren, 1995, No. 3, p7-9. J. Dawes, "An Induction to Friction Ion Stir Welding a Developments", Welding & Metal Fabrication, TWI, February 13, 1995, Vol. 63, No. 1, p. 13-14 (58) Field surveyed (Int. Cl. ⁷ , DB name) B23K 20/12

Claims (1)

(57) [Claims] 1. A notch for fitting is provided at an intermediate portion in a longitudinal direction.
Are metallic members to each other consisting of aluminum hollow member or a solid material, so as to face with each other said notch
Te, along with the angle of the cross are combined in the fitting state without looseness in a cross state of 30 to 150 °, the metal member to each other by friction welding method for joining soften at the frictional heat using a rotating shaft And a joining structure of metal members, which are joined and integrated at their fitting portions.