Joined body, joined structure, and battery frame

Abstract

To provide a joined body in which an aluminum extension material and an aluminum cast are joined to each other with high strength, and a joined structure, and a battery frame.SOLUTION: A joined body 200 is formed by joining an aluminum extension material 19 and an aluminum cast 21. The aluminum extension material 19 has a joining surface 23 extending in an extrusion direction of the aluminum extension material 19 and a surface width direction perpendicular to the extrusion direction. Side wall surfaces 25 extending in a surface thickness direction perpendicular to both the extrusion direction and the surface width direction are connected to both ends in a surface width direction of the joining surface 23. A recessed groove 27 recessed in the surface width direction is formed along the extrusion direction, on the side wall surface 25. The aluminum cast 21 includes: a joint surface-facing part 31 that covers the joining surface 23 of the aluminum extension material 19 and has a diffusion bonding surface where the aluminum extension material 19 and the aluminum cast 21 are diffusion-bonded; and an engaging part 34 that extends from the joint surface-facing part 31, covers the side wall surface, and engages with the recessed groove 27.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a joined body, a joined structure, and a battery frame.

Background Art

[0002] Conventionally, there has been a demand for improving the safety of passengers in vehicles, and for this purpose, the strength of vehicle bodies has been improved. On the other hand, against the backdrop of the intensification of problems such as global warming, the movement to improve the fuel efficiency of automobiles has been accelerating. It is known that weight reduction of the vehicle body is effective for improving fuel efficiency. For example, as a manufacturing technique for aluminum casting products in which a metal material is inserted, a cylinder block in which a cast iron cylinder liner is cast in an aluminum casting is disclosed in Patent Document 1. According to this manufacturing method, by setting the cylinder liner in a mold and pouring a molten aluminum alloy into the cavity of the mold, a cylinder block in which the cylinder liner is cast in an aluminum alloy can be obtained.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, technological development is underway to manufacture large parts such as frames for automobiles using die-cast inserts. For example, even in battery frames that house batteries for motor driving mounted in EVs (Electric Vehicles), HEVs (Hybrid Electric Vehicles), etc., large die-cast insert parts are required. However, at the joint between an aluminum extruded material and an aluminum casting, the larger the die-cast insert part becomes, the greater the external force acting on it, and it is easier for looseness to occur at the joint between the two. Also, when incomplete parts such as air bubbles occur in the aluminum casting, there is a risk that the joint strength will decrease significantly, such as the joint interface peeling off due to an external force.

[0005] Therefore, an object of the present invention is to provide a joined body, a joining structure, and a battery frame in which an aluminum extruded material and an aluminum casting are joined with high strength.

Means for Solving the Problems

[0006] The present invention has the following configuration. (1) A joined body in which an aluminum extruded material and an aluminum casting are joined, The aluminum extruded material has a joining surface that extends along the extrusion direction of the aluminum extruded material and the surface width direction orthogonal to the extrusion direction, Side wall surfaces extending in the surface thickness direction orthogonal to the extrusion direction and the surface width direction are connected to both side ends of the joining surface in the surface width direction, Concave grooves recessed in the surface width direction are formed along the extrusion direction on the side wall surfaces, The aluminum casting has a joining surface facing portion that covers the joining surface of the aluminum extruded material and has a diffusion joining surface where the aluminum extruded material and the aluminum casting are diffusion-joined, and an engaging portion that extends from the joining surface facing portion, covers the side wall surface, and engages with the concave groove, including, joined body. (2) The bonded bodies described in (1) are arranged in a pair so that the aluminum extrusions face each other at positions separated in the surface thickness direction with the aluminum extrusions on the back side respectively. It further has a plurality of connecting aluminum castings that connect the pair of opposing aluminum castings. The aluminum casting and the plurality of connecting aluminum castings form at least a frame and are integrally cast. Bonded structure. (3) A battery frame formed using the bonded structure described in (2), in which a battery is housed inside the frame.

Advantages of the Invention

[0007] According to the present invention, an aluminum extrusion and an aluminum casting can be bonded with high strength.

Brief Description of the Drawings

[0008]

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DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, an example in which the joined body according to the present invention is applied to a battery frame mounted on an automobile and housing a battery will be described, but the application target is not limited to this.

[0010] <First Configuration Example> FIG. 1 is an overall perspective view of a joined structure 100. FIG. 2 is a plan view of the joined structure 100. The joined structure 100 shown in FIGS. 1 and 2 includes a pair of side members 11A and 11B arranged in parallel to each other, and cross members 13A and 13B connecting the pair of side members 11A and 11B. The cross member 13A is connected to one end portion of the side members 11A and 11B, and the cross member 13B is connected to an intermediate portion in the longitudinal direction of the side members 11A and 11B. The side members 11A and 11B and the cross members 13A and 13B are arranged perpendicular to each other. Thereby, a rectangular frame body 15 surrounded by a pair of side members 11A and 11B and a pair of cross members 13A and 13B is formed in the joined structure 100. Further, the pair of side members 11A and 11B extend from the frame body 15 to the outside of the frame body 15 to form protruding bars 17A and 17B, respectively.

[0011] Here, the longitudinal direction of the side members 11A and 11B is defined as the X direction, the longitudinal direction of the cross members 13A and 13B is defined as the Y direction, and the direction orthogonal to both the X direction and the Y direction is defined as the Z direction. Also, in the drawings shown hereinafter, the same reference numerals are given to the same members and parts to simplify or omit their descriptions.

[0012] FIG. 3 is a schematic arrow view of the corner portion of the joining structure 100 shown in FIG. 1 as viewed from the V1 direction. The side member 11A (similarly for 11B) is formed by an aluminum extrusion material 19 which is an insert material and an aluminum casting 21 which surrounds the aluminum extrusion material 19. The cross members 13A and 13B are formed by connecting aluminum castings 22 and are cast integrally with the aluminum casting 21. That is, the aluminum casting 21 forms the side members 11A and 11B together with the aluminum extrusion material 19, and the connecting aluminum casting 22 forms the cross members 13A and 13B. Then, the aluminum casting 21, the aluminum extrusion material 19, and the connecting aluminum casting 22 are integrated to form the joining structure 100.

[0013] FIG. 4 is a perspective view showing the aluminum extrusion material 19 constituting the side member 11A (similarly for 11B) shown in FIG. 3. The aluminum extrusion material 19 is an extrusion material made of aluminum or an aluminum alloy with the above-described Y direction as the extrusion direction. The aluminum extrusion material 19 has a joining surface 23 that extends along the extrusion direction (Y direction) of the aluminum extrusion material 19, the extrusion direction, and the surface width direction (Z direction) orthogonal to the extrusion direction. Side wall surfaces 25 that extend in the surface thickness direction (X direction) orthogonal to both the extrusion direction (Y direction) and the surface width direction (Z direction) are connected to both end sides in the surface width direction (Z direction) of the joining surface 23.

[0014] FIG. 5 is a side view showing an enlarged view of the P1 portion in FIG. 3. The side wall surface 25 is recessed toward the inside in the surface width direction (Z direction) and has a concave groove 27 that extends along the extrusion direction (Y direction). Of the pair of groove end portions 27a of the concave groove 27, the groove end portion 27a on the joining surface 23 side forms a protruding portion 29 that protrudes in the surface width direction (Z direction).

[0015] FIG. 6 is an explanatory diagram showing a state in which the aluminum extruded material 19 is cast into the aluminum casting 21. The aluminum casting 21 includes a joint surface facing portion 31 that covers the joint surface 23 of the aluminum extruded material 19 and has a diffusion joint surface where the aluminum extruded material 19 and the aluminum casting 21 are diffusion joined, and an engaging portion 34 that extends from the joint surface facing portion 31 to cover the side wall surface 25 and engages with the concave groove 27. That is, the joining structure 100 includes a plurality (two in this configuration) of joined bodies 200 in which the engaging portion 34 of the aluminum casting 21 engages with the concave groove 27 of the aluminum extruded material 19. Further, the diffusion joining portion included in the joint surface facing portion 31 is preferably formed over the entire joint interface between the aluminum extruded material 19 and the aluminum casting 21, but may be formed in the vicinity of the engaging portion 34 or over the entire joint surface 23 depending on the joining conditions.

[0016] As described above, the joining structure 100 shown in FIG. 1 includes a pair of aluminum extruded materials 19 arranged to face each other at positions separated in the surface thickness direction (Y direction) with the aluminum extruded materials 19 on the back side, and further includes a plurality (two in this configuration) of connecting aluminum castings 22 that connect the pair of opposing aluminum castings 21. The aluminum casting 21 and the plurality of connecting aluminum castings 22 are integrally cast to form at least one frame body 15.

[0017] According to the joined body 200 and the joining structure 100 having the above-described configuration, the engaging portion 34 of the aluminum casting 21 engages with the pair of concave grooves 27 of the aluminum extruded material 19, respectively, to exhibit an anchor effect. As a result, the aluminum casting 21 and the aluminum extruded material 19 are firmly fixed, and peeling at the interface between the two is less likely to occur. As a result, the aluminum casting 21 and the aluminum extruded material 19 can be maintained with high joining strength.

[0018] Moreover, by providing the protruding portion 29 extending from the concave groove 27, the engagement between the protruding portion 29 and the aluminum casting 21 can be made stronger. For example, even if thermal shrinkage occurs in the aluminum casting 21 as indicated by the arrow S during casting, the protruding portions 29 at both ends in the surface width direction (Z direction) of the aluminum extrusion 19 securely lock the aluminum casting 21. Therefore, it is possible to prevent the interface between the aluminum casting 21 and the aluminum extrusion 19 from peeling off and the mutual bonding from loosening.

[0019] Particularly, when the joined body 200 and the joining structure 100 become larger in size, the external forces acting on each part increase, and large shear forces, tensile forces, etc. are likely to act on the above-described interface. Even in such a case, the aluminum extrusion 19 and the aluminum casting 21 are securely joined to each other by the concave groove 27 and the engaging portion 34. Further, the rigidity of the joining structure 100 can be improved and deformation can be suppressed by the engagement between the concave groove 27 and the engaging portion 34.

[0020] Also, it is preferable to provide the reinforcing ribs 33 at appropriate intervals on the aluminum casting 21 as shown in FIGS. 1 to 3. By providing the ribs 33, the rigidity of the joining structure 100 can be further improved.

[0021] FIG. 7 is a side view showing a configuration example of a joining structure 100A using an aluminum extrusion 19A having a hollow portion 37. One or a plurality of hollow portions 37 may be formed in the joining structure 100A along the extrusion direction (Y direction). By providing the hollow portion 37, weight reduction and reduction of material costs can be achieved.

[0022] Figs. 8 and 9 are schematic perspective views showing a configuration in which an accessory member 39 is provided in the joining structure 100 shown in Fig. 1. In the joining structure 100A shown in Fig. 8, the accessory member 39 is fixed to the surface outside the frame of the aluminum extrusion 19 that constitutes the side members 11A and 11B, that is, the surface not cast by the aluminum casting 21. The accessory member 39 may be, for example, an extrusion made of aluminum or an aluminum alloy, or a metal other than aluminum, or may be a resin material. When the accessory member 39 is an extrusion, generally the surface properties of the extrusion are uniform and the dimensional accuracy is relatively high, so positioning and joining with the mating member are facilitated. Further, by providing a hollow portion 40 in the accessory member 39, the overall rigidity can be increased.

[0023] The accessory member 39 shown here is a hollow extrusion made of aluminum and is a reinforcing member provided along the longitudinal direction (X direction) of the side members 11A and 11B. The accessory member 39 can be joined to the aluminum extrusion 19 that constitutes the side members 11A and 11B by spot welding, arc welding, laser welding, or the like.

[0024] In the joining structure 100A of this configuration, the protruding bars 17A and 17B protruding from the frame 15 can be reinforced by joining the accessory member 39 along their longitudinal direction (the extrusion direction X of the aluminum extrusion 19).

[0025] Further, the accessory member 39 may be provided in a direction intersecting the longitudinal direction (X direction) of the side members 11A and 11B as shown in Fig. 9. In this joining structure 100B, one end of the accessory member 39 is joined to the middle portion in the longitudinal direction of the aluminum extrusion 19, and the accessory member 39 extends along the Z direction from the middle portion in the longitudinal direction. The position where the accessory member 39 is joined to the aluminum extrusion 19 and the direction in which it extends from the aluminum extrusion 19 can be arbitrarily set according to the usage conditions of the joining structure 100B and the like. Thus, since the accessory member 39 can be arranged parallel or intersecting the longitudinal direction of the aluminum extrusion 19, the joining direction with the mating member to be connected can be freely selected, and the installation freedom degree of the joining structure 100B can be improved.

[0026] In the joint structure 100B of this configuration, an accessory member 39 is provided upward from the frame body 15, and the joint structure 100B can be arranged below the mating member connected to the accessory member 39.

[0027] FIG. 10 is an overall perspective view of a joint structure 100C using an aluminum extruded material 19B having a hollow portion 35. The aluminum extruded materials 19B constituting the side members 12A and 12B of this configuration have a plurality of hollow portions 35, and the surfaces on the side where the cross members 13A and 13B are formed are cast by an aluminum casting 21. Further, the cross members 13A and 13B are formed by a connecting aluminum casting 22 and are cast integrally with the aluminum casting 21.

[0028] FIG. 11 is a schematic arrow view of the corner of the joint structure 100C shown in FIG. 10 as viewed from the V2 direction. FIG. 12 is a side view of the aluminum extruded material 19B shown in FIG. 10. The aluminum extruded material 19B shown here has two hollow portions 35 and its rigidity is enhanced. At the corners of the hollow portion 35 on the aluminum casting 21 side of the aluminum extruded material 19B, concave grooves 27A having a substantially circular cross-sectional shape are formed along the extrusion direction (Y direction). In the aluminum extruded material 19B of this configuration, a combination of the joint surface 23 and a pair of concave grooves 27A at both ends in the surface width direction (Z direction) of the joint surface 23 is repeatedly arranged along the surface width direction (Z direction). One (corner) or two (flat portion) groove end portions 27a arranged on the joint surface 23 side of the concave groove 27A form a protruding portion 29A protruding in the surface width direction (Z direction).

[0029] FIG. 13 is a partially enlarged side view showing an enlarged view of the concave groove 27A of the aluminum extruded material 19B. In a cross section orthogonal to the extrusion direction (Y direction), the concave groove 27A having a circular inner wall surface preferably has an inner peripheral surface diameter φd of 5 mm or more. Further, the wall thickness around the concave groove 27A of the aluminum extruded material 19B is preferably 2 mm or more. The opening between the pair of groove ends 27a preferably has a central angle θ from the center O of the concave groove 27A of 35° or more and 90° or less. By setting the concave groove 27A to the shape within the above range, the engagement with the aluminum casting 21 filled in the concave groove 27A becomes good, and the joining strength between the concave groove 27A and the aluminum casting 21 can be improved.

[0030] FIG. 14 is a partial side view of a joined structure showing a state in which the aluminum casting 21 is cast around the aluminum extruded material 19B. In the side member 12A (similarly for 12B) of this configuration, the joining surface 23 of the aluminum extruded material 19B is covered by the joining surface facing portion 31 of the aluminum casting 21, and the engaging portion 34 of the aluminum casting 21 is formed in the concave groove 27A of the aluminum extruded material 19B. Thereby, the interface between the aluminum extruded material 19B and the aluminum casting 21 is less likely to be peeled off by a plurality of engaging portions 34 provided along the surface width direction (Z direction) of the aluminum extruded material 19B. That is, even when the shrinkage shown by the arrow S acts due to thermal contraction during the casting of the aluminum casting 21, the engagement between the concave groove 27A and the engaging portion 34 and the protruding portion 29 can prevent the occurrence of peeling and damage. As a result, the aluminum extruded material 19B and the aluminum casting 21 are joined with high joining strength, and the rigidity of the joined structure 100C can be improved.

[0031] Thus, even if the joining surface 23 of the aluminum extruded material 19B has a large area, a plurality of engaging portions 34 are provided by repeatedly arranging the combination of the joining surface 23 and the concave grooves 27A at both ends of the joining surface 23 along the surface width direction (Z direction). Thereby, a high joining strength between the aluminum extruded material 19B and the aluminum casting 21 can be surely maintained.

[0032] FIG. 15 is a perspective view showing a rectangular joint structure 100D. The joint structure can be arbitrarily changed according to the shape and part of the structure on which the joint structure is mounted. The joint structure 100D shown here is rectangular and does not include the protruding bars 17A and 17B described above, but it can be in various other forms.

[0033] The joint structures of the above-described respective configurations can be applied to, for example, an automotive battery frame. In that case, a battery pack is accommodated in the inner space of the frame body 15 in the joint structure of each configuration. According to this configuration, since the battery frame can be integrally formed by die-cast insert molding, the process of combining and joining a plurality of side members and cross members during assembly to the vehicle can be simplified. Thereby, the work of assembling the battery frame to the vehicle can be reduced, and the tact time of assembly can be shortened. Further, since the side members and cross members of the joint structure are joined with high joint strength, even if the external force applied increases with the increase in the size of the member, the occurrence of peeling and damage can be suppressed. Therefore, a highly reliable battery frame can be provided with improved assembly workability. Note that the battery frame is an example, and it may be a frame for assembling other parts. In addition to automobiles, the above-described joint structure can also be applied to frames in other fields such as building frames, frames for mechanical devices, and frames for plant facilities.

[0034] In addition, the above-described aluminum extruded material preferably uses aluminum alloys such as 5000 series, 6000 series, and 7000 series according to JIS or AA standards in terms of having excellent strength and being able to be made thinner. These hollow extruded shapes of aluminum alloy can preferably use those manufactured by appropriately combining heat treatment processes such as casting (DC casting method or continuous casting method), homogenization heat treatment, hot extrusion, solution treatment and quenching treatment, and, if necessary, artificial aging treatment. Further, examples of the above-described aluminum castings include Al-Si-based, Al-Mg-based alloys, Al-Cu-Mg-based alloys, Al-Si-Cu-based alloys, Al-Si-Mg-based alloys, Al-Si-Cu-Mg-Ni-based alloys, hypereutectic Al-Si-based alloys, and the like.

[0035] As described above, the following matters are disclosed in this specification. (1) A joined body in which an aluminum extruded material and an aluminum casting are joined, wherein the aluminum extruded material has a joining surface extending along the extrusion direction of the aluminum extruded material and the surface width direction orthogonal to the extrusion direction, side wall surfaces extending in the surface thickness direction orthogonal to the extrusion direction and the surface width direction are connected to both side ends of the joining surface in the surface width direction, concave grooves recessed in the surface width direction are formed along the extrusion direction on the side wall surfaces, the aluminum casting has a joining surface facing portion that covers the joining surface of the aluminum extruded material and has a diffusion joining surface where the aluminum extruded material and the aluminum casting are diffusion joined, and an engaging portion that extends from the joining surface facing portion, covers the side wall surface, and engages with the concave groove, including a joined body. According to this joined body, by engaging the engaging portions of the aluminum casting with the pair of concave grooves of the aluminum extruded material, an anchor effect can be exerted to firmly fix the aluminum casting and the aluminum extruded material. As a result, it becomes difficult for the aluminum extruded material and the aluminum casting to separate, and high joining strength of both can be maintained.

[0036] (2) The joined body according to (1), having a protruding portion protruding in the surface width direction at the groove end portion on the joining surface side in the surface thickness direction of the concave groove. According to this joined body, the engagement with the aluminum casting can be made stronger by the protruding portion of the aluminum extruded material.

[0037] (3) The joined body according to (1), wherein the set of the joining surface and the concave grooves at both side ends of the joining surface are repeatedly arranged along the surface width direction. According to this joined body, since a plurality of sets of joining surfaces and concave grooves are integrally formed, even with a large joining area, high joining strength between the aluminum extruded material and the aluminum casting can be maintained.

[0038] (4) The joining bodies according to any one of (1) to (3) are arranged in a pair so that the aluminum extruded materials face each other at positions separated in the surface thickness direction with the aluminum extruded materials on the back side respectively, further comprising a plurality of connecting aluminum castings for connecting the pair of opposing aluminum castings, the aluminum casting and the plurality of connecting aluminum castings are integrally cast at least forming a frame body, Joining structure. According to this joining structure, since the aluminum casting is integrally formed with the connecting aluminum casting, the shape of the joining structure having a frame body can be easily obtained.

[0039] (5) The joining structure according to (4), wherein an auxiliary member extending in one direction is provided on the outer surface of the frame body of the aluminum extruded material. According to this joining structure, the degree of freedom in the shape of the joining structure can be improved.

[0040] (6) The joining structure according to (5), wherein the auxiliary member is an extruded material. According to this joining structure, since the surface of the extruded material is uniform and the dimensional accuracy is relatively high, positioning and joining with a mating member are facilitated, and connection to the aluminum extruded material can be achieved with high strength.

[0041] (7) The joining structure according to (6), wherein the auxiliary member is arranged parallel or intersecting with the extrusion direction. According to this joining structure, by arranging the auxiliary member in the longitudinal direction of the aluminum extruded material, the aluminum extruded material can be reinforced. Also, by arranging it intersecting the longitudinal direction of the aluminum extruded material, the joining direction with the mating member of the joining structure can be freely selected, and the degree of freedom in installing the joining structure can be improved.

[0042] (8) The joining structure according to (6), wherein the auxiliary member has a hollow portion. According to this joining structure, by providing the hollow portion, weight reduction can be achieved while increasing the rigidity of the auxiliary member.

[0043] A battery frame formed by using the joining structure described in (4) and having a battery accommodated inside the frame body.

[0044] According to this battery frame, a structure with high strength and excellent workability in installation can be achieved.

Explanation of Signs

[0045] 11A, 11B, 12A, 12B Side members 13A, 13B Cross members 15 Frame body 17A, 17B Protruding bars 19, 19A, 19B Aluminum extrusions 21 Aluminum castings 22 Connecting aluminum castings 23 Joining surface 25 Side wall surface 27, 27A Concave grooves 27a Groove end 29, 29A Protrusions 31 Joining surface facing part 33 Ribs 34 Engaging part 35, 37, 40 Hollow parts 39 Auxiliary members 100, 100A, 100B, 100C, 100D Joining structures 200 Joined body

Claims

1. A joined body in which an aluminum extruded material and an aluminum casting are joined, wherein the aluminum extruded material has a joining surface extending along the extrusion direction of the aluminum extruded material and a surface width direction orthogonal to the extrusion direction, side wall surfaces extending in a surface thickness direction orthogonal to the extrusion direction and the surface width direction are connected to both side ends of the joining surface in the surface width direction, a concave groove recessed in the surface width direction is formed along the extrusion direction on the side wall surface, the aluminum casting has a joining surface facing portion that covers the joining surface of the aluminum extruded material and has a diffusion joining surface where the aluminum extruded material and the aluminum casting are diffusion joined, and an engaging portion that extends from the joining surface facing portion, covers the side wall surface, and engages with the concave groove, including, a joined body.

2. The joined body according to claim 1, wherein a protruding portion protruding in the surface width direction is provided at a groove end portion on the joining surface side in the surface thickness direction of the concave groove. The joined body according to claim 1.

3. The joined body according to claim 1, wherein a set of the joining surface and the concave grooves at both side ends of the joining surface is repeatedly arranged along the surface width direction. The joined body according to claim 1.

4. A pair of the joined bodies according to any one of claims 1 to 3 are arranged to face each other at positions separated in the surface thickness direction with the aluminum extruded materials on their respective back sides, and further include a plurality of connecting aluminum castings that connect the pair of opposing aluminum castings, wherein the aluminum casting and the plurality of connecting aluminum castings are integrally cast at least forming a frame body. A joined structure.

5. An additional member extending in one direction is provided on an outer surface of the frame body of the aluminum extruded material. The joined structure according to claim 4.

6. The additional member is an extruded material. The joined structure according to claim 5.

7. The additional member is arranged parallel or intersecting with the extrusion direction. The joined structure according to claim 6.

8. The additional member has a hollow portion. The joined structure according to claim 6.

9. A battery frame formed using the joined structure according to claim 4, in which a battery is housed inside the frame body.

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