Battery case for automobile

Abstract

To reduce the number of assembling steps and to increase the efficiency of equipping a battery in a battery case for an automobile.SOLUTION: A battery case 10 for an automobile includes: a frame 100 in which a plurality of pressing materials 110, 120, 130, and 140 are arranged in a frame; and a resin material 200 integrally formed with the frame 100. The resin material 200 includes: a bottom wall 210 arranged below the frame 100, bottom surfaces 112, 122, and 132 of the frame 100 being buried in the bottom wall 210; and a surrounding wall 220 arranged outside the frame 100 in a horizontal direction, the outer side surface of the frame 100 in a horizontal direction being buried in the surrounding wall 220.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a battery case for an automobile. [Background technology]

[0002] Electric vehicles and other electrically powered vehicles need to be equipped with large-capacity batteries to ensure sufficient driving range, while at the same time requiring a spacious cabin. To meet both of these requirements, many electric vehicles house large-capacity batteries in a battery case that is mounted on the entire underfloor area of ​​the vehicle. Therefore, battery cases for electric vehicles require high sealing properties to prevent water from entering from the road surface and to prevent malfunctions of electronic components, as well as high crash strength to protect the battery inside.

[0003] For example, Patent Document 1 discloses a battery case for electric vehicles that includes a tray formed into a bathtub shape by pressing a metal plate and a frame made of an aluminum alloy extrusion material that is arranged around the tray. The tray provides high sealing properties while the frame provides high impact strength. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-41783 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the tray is formed by press molding, so it is not possible to completely eliminate the roundness of the inner surface of the tray in consideration of moldability. Therefore, when a battery is housed in the tray, a gap occurs between the tray and the battery due to the roundness. In other words, there is room for improvement in battery mounting efficiency. In addition, since it is necessary to join the frame and the tray, many assembly steps are required.

[0006] An object of the present invention is to improve the battery mounting efficiency and reduce the number of assembly steps in an automobile battery case. [Means for solving the problem]

[0007] The present invention relates to A frame in which a plurality of extrusion members are arranged in a frame shape; A resin material integrally molded with the frame; Equipped with The resin material is A bottom wall is disposed below the frame, and a bottom surface of the frame is embedded in the bottom wall; a peripheral wall disposed around the horizontal outside of the frame and having the horizontal outside side surface of the frame buried therein; The present invention provides a battery case for an automobile, comprising:

[0008] According to this configuration, the resin material and the frame are integrally molded to form the bottom wall and the surrounding wall, and at the same time, the multiple extrusions are fixed in a frame shape to form the frame, so that the number of assembly steps can be reduced. Specifically, the process of joining multiple extrusions in a frame shape to form the frame and the process of joining a separate member such as a bottom plate to the frame can be omitted or simplified. In addition, the flexible moldability of the resin material allows the battery storage space to be formed without roundness, and the battery mounting efficiency can be improved. In addition, the bottom wall and the surrounding wall that form the outer surface are integrally formed with the resin material without any seams, so that a high sealability that prevents water from entering from the outside can be ensured. Here, burying includes not only the case where the entirety is completely buried, but also the case where a part is buried (i.e., a part is exposed).

[0009] The plurality of extrusion materials include A pair of side members extending in the front-rear direction of the vehicle body; a cross member extending in the vehicle body width direction and connecting the pair of side members; may include:

[0010] According to this configuration, the pair of side members can support loads in the fore-and-aft direction of the vehicle body, and the cross member can support loads in the width direction of the vehicle body, thereby ensuring high strength.

[0011] At least one set of the plurality of extrusion members may be welded to one another. Also, at least one set of the plurality of extrusion members may be fastened to one another by a bracket.

[0012] According to these configurations, at least one set of the multiple extrusion materials is not only fixed with the resin material but also bonded to each other separately, so that the frame can be fixed more firmly than when it is simply fixed with the resin material. Also, since the shape of the frame can be fixed to some extent before integral molding with the resin material, the frame can be easily handled during integral molding.

[0013] The resin material may have a flange wall extending horizontally outward from the peripheral wall, A metal vehicle body joining member that enables joining to a vehicle body may be embedded in the flange wall.

[0014] With this configuration, the battery case and the vehicle body can be firmly fixed together via the vehicle body joining member.

[0015] The bottom wall may have a metallic battery connection member embedded therein to enable connection with a battery.

[0016] According to this configuration, the battery case and the battery can be firmly fixed together via the battery joint member.

[0017] A metal bottom plate may be embedded in the bottom wall.

[0018] According to this configuration, the bottom plate can protect the battery from impacts from the road surface, ensuring high battery protection performance. Effect of the Invention

[0019] According to the present invention, in an automobile battery case, it is possible to improve the battery mounting efficiency and reduce the number of assembly steps. [Brief description of the drawings]

[0020] [Figure 1] Side view of an electric car. [Diagram 2] FIG. 1 is a perspective view of an automobile battery case according to a first embodiment. [Diagram 3] 3 is a perspective view of the automobile battery case taken along line III-III in FIG. 2. [Figure 4] 4 is a cross-sectional view of an automobile battery case as viewed from the direction of arrow IV in FIG. 3. [Diagram 5] 4 is a cross-sectional view of an automobile battery case as viewed from the direction of arrow V in FIG. 3. [Figure 6] FIG. 4 is a perspective view of a modified example of a battery case for an automobile shown in FIG. 3. [Figure 7] FIG. 6 is a perspective view of an automobile battery case according to a second embodiment. [Figure 8] 8 is a perspective view of the automobile battery case taken along line VIII-VIII in FIG. 7. [Figure 9] 9 is a cross-sectional view of an automobile battery case as viewed in the direction of an arrow IX in FIG. 8 . [Figure 10] 9 is a cross-sectional view of the automobile battery case as viewed in the direction of the arrow X in FIG. 8 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0022] (First embodiment) With reference to FIG. 1, automobile 1 is an electric vehicle that runs by driving a motor with electric power supplied from a battery 2. Automobile 1 is a vehicle that runs on electric power, and may be, for example, an electric vehicle or a plug-in hybrid vehicle. The type of vehicle is not particularly limited, and may be a passenger car, a truck, a work vehicle, or other mobility. In the following, a case where automobile 1 is a passenger car type electric vehicle will be described as an example.

[0023] The automobile 1 is equipped with a driving motor and high-voltage equipment in the front part 3 of the vehicle body. The automobile 1 also has an automobile battery case 10 (hereinafter also simply referred to as the battery case 10) that stores a battery 2 over almost the entire surface under the floor of the passenger compartment R in the center part 4 of the vehicle body. In Fig. 1, the front-rear direction of the automobile 1 (front-rear direction of the vehicle body) is indicated as the X direction, and the up-down direction (up-down direction of the vehicle body) is indicated as the Z direction. The same notation is used in the subsequent figures, and in Fig. 2 and onwards, the width direction of the automobile 1 (vehicle width direction) is indicated as the Y direction.

[0024] Referring to FIG. 2, the battery case 10 has a frame 100 in which a plurality of extrusion materials 110, 120, 130, 140 are arranged in a frame shape, and a resin material 200 molded integrally with the frame 100. The plurality of extrusion materials 110, 120, 130, 140 are made of metal, for example, aluminum alloy. The plurality of extrusion materials 110, 120, 130, 140 are obtained by heating and compressing a billet-shaped metal material in the main body of an extrusion molding machine and extruding it from a die attached to the main body. After extrusion from the die, required processes such as cooling, taking out, and cutting are performed. In addition, the resin material 200 is realized by, for example, fiber reinforced plastic (FRP) in which fibers are impregnated into a matrix resin.

[0025] 2 shows one battery 2 as a schematic rectangular parallelepiped removed from the battery case 10. However, in reality, a plurality of batteries 2 of the same shape are stored in the battery case 10. Note that FIG. 2 shows a state in which the lid of the battery case 10 has been removed so that the inside of the battery case 10 can be seen.

[0026] The frame 100 constitutes the skeleton of the battery case 10. The frame 100 has a rectangular outer shape in a plan view (viewed in the Z direction). However, the outer shape of the frame 100 is not limited to a rectangle and may be any polygonal shape. The frame 100 plays a role in protecting the battery 2 placed inside.

[0027] In this embodiment, the multiple extrusion members 110, 120, 130, 140 of the frame 100 include a pair of side members 110, a front member 120, a rear member 130, and a cross member 140. Note that in this embodiment, the pair of side members 110, the front member 120, the rear member 130, and the cross member 140 are not welded to each other.

[0028] The pair of side members 110 are disposed apart in the vehicle body width direction and extend in the vehicle body front-rear direction. The front member 120 extends in the vehicle body width direction and connects the front ends of the pair of side members 110. The rear member 130 extends in the vehicle body width direction and connects the rear ends of the pair of side members 110. The cross member 140 extends in the vehicle body width direction and connects the center portions of the pair of side members 110 in the vehicle body front-rear direction.

[0029] 3 and 4, the rear member 130 has a generally J-shape in a cross section perpendicular to the vehicle body width direction. The rear member 130 has a closed cross-sectional shape that defines a plurality of chambers r1 to r3. In the illustrated example, the plurality of chambers r1 to r3 are arranged side by side in the vehicle body up-down direction.

[0030] A horizontally outer side surface 131 of the rear member 130 is inclined horizontally inward and downward with respect to the vertical direction. Here, the horizontally inner side refers to the center side of the frame 100 in a plan view, and the horizontally outer side refers to the opposite side. A bottom surface 132 of the rear member 130 is inclined horizontally inward and downward with respect to the horizontal direction. A horizontally inner side surface 133 of the rear member 130 extends along the vertical direction, and a top surface 134 extends along the horizontal direction.

[0031] The rear member 130 has a groove-shaped rear engagement portion 135 at an upper corner on the horizontal outer side. The rear engagement portion 135 engages with the resin material 200. The rear member 130 also has a hook-shaped rear hook portion 136 that protrudes horizontally inward at a lower corner on the horizontal inner side. The rear hook portion 136 does not engage with the resin material 200, and is hooked on a mold during the manufacturing process to fix the position of the rear member 130 relative to the mold. The rear member 130 also has a rear protrusion portion 137 that protrudes horizontally outward at a lower corner on the horizontal outer side. The rear protrusion portion 137 is embedded in the resin material 200, and plays a role in fixing the position of the rear member 130. The rear engagement portion 135, the rear hook portion 136, and the rear protrusion portion 137 may be omitted as necessary.

[0032] The front member 120 has the same shape as the rear member 130. That is, the front member 120 has a side surface 121, a bottom surface 122, a side surface 123, and a top surface 124 (see the symbols in parentheses in FIG. 4). Similarly, the front member 120 has a front engagement portion 125, a front hook portion 126, and a front protrusion portion 127 (see the symbols in parentheses in FIG. 4). Note that the front engagement portion 125, the front hook portion 126, and the front protrusion portion 127 may be omitted as necessary.

[0033] 3 and 5, each of the pair of side members 110 has a substantially I-shape in a cross section perpendicular to the vehicle body longitudinal direction. Each of the pair of side members 110 has a closed cross-sectional shape having a plurality of chambers r4 to r6 in a cross section perpendicular to the vehicle body longitudinal direction. In the illustrated example, the plurality of chambers r4 to r6 are arranged side by side in the vehicle body vertical direction.

[0034] A horizontally outer side surface 111 of each of the pair of side members 110 is inclined horizontally inward and downward with respect to the vertical direction. A bottom surface 112 of each of the pair of side members 110 is inclined horizontally inward and downward with respect to the horizontal direction. A horizontally inner side surface 113 of each of the pair of side members 110 extends along the vertical direction, and a top surface 114 extends along the horizontal direction.

[0035] Each of the pair of side members 110 has a groove-shaped side engagement portion 115 at an upper corner on the horizontal outside. Each of the pair of side members 110 also has a side protrusion portion 116 that protrudes horizontally outward at a lower corner on the horizontal outside. The side protrusion portion 116 is embedded in the resin material 200, and serves to fix the position of each of the pair of side members 110. Each of the pair of side members 110 does not have a portion that protrudes horizontally inward, such as the rear hook portion 136 (see FIG. 4). The side engagement portion 115 and the side protrusion portion 116 may be omitted as necessary.

[0036] 3 and 4, the cross member 140 has a generally I-shape in a cross section perpendicular to the vehicle body width direction. The cross member 140 has a closed cross-sectional shape having a plurality of chambers r7-r8 in a cross section perpendicular to the vehicle body width direction. In the illustrated example, the plurality of chambers r7-r8 are arranged side by side in the vehicle body up-down direction.

[0037] The side surfaces 141, 142 of the cross member 140 extend vertically, and the top surface 143 and the bottom surface 144 extend horizontally. The bottom surface 144 is provided at a position slightly higher than the lower ends of the side surfaces 141, 142. That is, the side surfaces 141, 142 of the cross member 140 extend downward beyond the bottom surface 144, and an opening 145 that opens downward is formed. At the end of the opening 145, a cross protrusion 146 is provided that protrudes to the front and rear sides in the longitudinal direction of the vehicle body. A resin material 200 is inserted into the opening 145 to fix the cross member 140. The cross protrusion 146 may be omitted as necessary.

[0038] 2 to 5, resin material 200 has a container shape disposed so as to enclose frame 100 from below and from the horizontal outside. Specifically, resin material 200 has bottom wall 210 disposed below frame 100, in which bottom surfaces 112, 122, 132 of frame 100 are embedded, and peripheral wall 220 disposed circumferentially on the horizontal outside of frame 100, in which side surfaces 111, 121, 131 on the horizontal outside of frame 100 are embedded.

[0039] The bottom wall 210 forms the lower surface of the battery accommodating space S in which the battery 2 is accommodated. The side surfaces of the battery accommodating space S are formed by the side surfaces 113 of the pair of side members 110, the side surface 123 of the front member 120, and the side surface 133 of the rear member 130. The upper surface of the battery accommodating space S is formed by the lower surface of the lid of the battery case 10.

[0040] The bottom wall 210 is provided with a first protruding portion 211 that extends in a bulging manner in the vehicle width direction. The first protruding portion 211 is disposed between the cross members 140 adjacent to each other in the vehicle front-rear direction, between the cross member 140 and the rear member, and between the cross member 140 and the front member 120. In the illustrated example, the first protruding portion 211 does not abut against any of the cross member 140, the front member 120, or the rear member 130. A metal battery connection member 20 that enables connection to the battery 2 is embedded in the first protruding portion 211. In the illustrated example, a collar member for inserting a bolt is embedded in the resin material 200 as the battery connection member 20. The upper and lower surfaces of the battery connection member 20 are exposed from the resin material 200. The battery 2 is fixed in position by being fastened to the battery case 10 via the battery connection member 20 with a bolt and nut.

[0041] Further, the bottom wall 210 is provided with a second protruding portion 212 that protrudes and extends in the vehicle body width direction in order to fix the front member 120 and the rear member 130. The second protruding portion 212 abuts against the front hook portion 126 and the rear hook portion 136.

[0042] In addition, the bottom wall 210 is provided with a protrusion 213 that protrudes upward so as to enter the inside of the cross member 140 from the opening 145. The protrusion 213 fits into the cross protrusion 146 to fix the position of the cross member 140.

[0043] The surrounding wall 220 rises vertically upward from the bottom wall 210 and constitutes a horizontal outer side surface of the battery case 10. In the illustrated example, the surrounding wall 220 has a rectangular outer shape in a plan view.

[0044] The surrounding wall 220 is provided with resin engagement portions 221 that engage with the side engagement portions 115 of the pair of side members 110, the front engagement portion 125 of the front member 120, and the rear engagement portion 135 of the rear member 130. The resin engagement portions 221 have a hook shape that can be hooked onto the concave shapes of the side engagement portions 115, the front engagement portion 125, and the rear engagement portion 135. The resin engagement portions 221 are arranged circumferentially in a plan view.

[0045] In this embodiment, the resin material 200 has a flange wall 230 that extends horizontally outward from the peripheral wall 220. In the illustrated example, the thickness of the flange wall 230 is greater than the thickness of the bottom wall 210.

[0046] A metallic vehicle body joining member 30 that enables joining to the vehicle body central part (vehicle body) 4 is embedded in the flange wall 230. In the illustrated example, a collar member for inserting a bolt is embedded in the resin material 200 as the vehicle body joining member 30. The upper and lower surfaces of the vehicle body joining member 30 are exposed from the resin material 200. The battery case 10 is fixed in position by fastening with bolts and nuts to the vehicle body central part (vehicle body) 4 via the vehicle body joining member 30.

[0047] The battery case 10 of the present embodiment provides the following advantages.

[0048] By integrally molding the resin material 200 and the frame 100, the bottom wall 210 and the surrounding wall 220 are formed, and at the same time, the multiple extrusion members 110, 120, 130, 140 are fixed in a frame shape to form the frame 100, so that the number of assembly steps can be reduced. Specifically, the process of joining the multiple extrusion members 110, 120, 130, 140 in a frame shape to form the frame 100 and the process of joining a separate member such as a bottom plate to the frame 100 can be omitted or simplified. In addition, the flexible moldability of the resin material 200 allows the battery storage space S to be formed without roundness, and the mounting efficiency of the battery 2 can be improved. In addition, the bottom wall 210 and the surrounding wall 220 that constitute the outer surface are integrally formed by the resin material 200 without any seams, so that high sealing properties that prevent water from entering from the outside can be ensured.

[0049] Furthermore, since the pair of side members 110 can support loads in the longitudinal direction of the vehicle body, and the cross member 140 can support loads in the width direction of the vehicle body, high strength can be ensured.

[0050] In addition, the battery case 10 and the vehicle center section (vehicle body) 4 can be firmly fixed together via the vehicle body joint member 30.

[0051] In addition, the battery case 10 and the battery 2 can be firmly fixed together via the battery joint member 20.

[0052] 6, the multiple extrusion members 110, 120, 130, 140 may be joined by another joining means in addition to the resin material 200. For example, at least one set of the multiple extrusion members 110, 120, 130, 140 may be welded to each other. Preferably, at least one set of the multiple extrusion members 110, 120, 130 constituting the outer periphery of the frame 100 is welded to each other. In the illustrated example, the pair of side member 110 and rear member 130 are welded to each other at the top surfaces 114, 134 (see welded points WP). However, the welded points WP may be provided at any point, not limited to the top surface.

[0053] At least one set of the multiple extrusion members 110, 120, 130, 140 may be fastened to each other by a bracket 40. In the illustrated example, a pair of side members 110 and cross members 140 are fastened to each other by a bracket 40. The bracket 40 is an L-shaped metal plate and configured to be capable of being fastened with bolts and nuts. Note that both welding and bracket fastening may be performed in a superimposed manner at the same location.

[0054] At least one set of the multiple extrusion materials 110, 120, 130, 140 is not only fixed by the resin material 200 but also bonded to each other separately, so that the frame 100 can be fixed more firmly than when it is simply fixed by the resin material 200. Also, since the shape of the frame 100 can be fixed to some extent before integral molding with the resin material 200, the frame 100 can be easily handled during integral molding.

[0055] Second embodiment 7 to 10, the second embodiment of the automotive battery case 10 is obtained by adding a bottom plate 50 to the first embodiment and omitting the battery connecting member 20. Other than these parts, the second embodiment is substantially the same as the first embodiment. Therefore, the description of the parts shown in the first embodiment may be omitted.

[0056] In this embodiment, a metal bottom plate 50 is embedded in the bottom wall 210 of the resin material 200. In the illustrated example, the lower surface of the bottom plate 50 is exposed from the resin material 200. In the illustrated example, the bottom plate 50 has a rectangular shape in a plan view and has approximately the same size as the outer shape of the peripheral wall 220. However, the arrangement, shape, or size of the bottom plate 50 is not particularly limited.

[0057] In this embodiment, the battery connecting member 20 in the first embodiment is not disposed on the bottom wall 210, and no holes are provided on the bottom wall 210. However, holes may be provided on the bottom plate 50 and the resin material 200, and the bottom plate 50 can thereby function as the battery connecting member 20.

[0058] According to the battery case 10 of this embodiment, the bottom plate 50 can protect the battery 2 against impacts from the road surface, ensuring high battery protection performance.

[0059] Although the specific embodiment of the present invention and its modified examples have been described above, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made within the scope of the present invention. For example, an appropriate combination of the contents of each embodiment may be one embodiment of the present invention.

[0060] The present disclosure may include the following aspects. (Aspect 1) A frame in which a plurality of extrusion members are arranged in a frame shape; A resin material integrally molded with the frame; Equipped with The resin material is A bottom wall is disposed below the frame, and a bottom surface of the frame is embedded in the bottom wall; a peripheral wall disposed around the horizontal outside of the frame and having the horizontal outside side surface of the frame buried therein; The battery case for an automobile has the following features: (Aspect 2) The plurality of extrusion materials include A pair of side members extending in the front-rear direction of the vehicle body; a cross member extending in the vehicle body width direction and connecting the pair of side members; 2. The automotive battery case of embodiment 1, comprising: (Aspect 3) 3. The automotive battery case according to claim 1 or 2, wherein at least one set of the plurality of extrusions are welded to each other. (Aspect 4) The automotive battery case according to any one of aspects 1 to 3, wherein at least one set of the multiple extrusions are fastened to each other with brackets. (Aspect 5) The resin material has a flange wall extending horizontally outward from the peripheral wall, 5. An automobile battery case according to any one of aspects 1 to 4, wherein a metal vehicle body joining member is embedded in the flange wall to enable joining to a vehicle body. (Aspect 6) 6. An automobile battery case according to any one of aspects 1 to 5, wherein a metal battery connection member is embedded in the bottom wall to enable connection to a battery. (Aspect 7) 7. An automobile battery case according to any one of aspects 1 to 6, wherein a metal bottom plate is embedded in the bottom wall. [Explanation of symbols]

[0061] 1. Automobiles 2 Battery 3 Front of the vehicle 4. Center of the vehicle 10. Automotive battery cases 20 Battery joint parts 30 Body joint parts 40 Bracket 50 Bottom plate 100 frames 110 Side member (extrusion material) 111 Side 112 Bottom 113 Side 114 Top 115 Side engagement part 116 Side protrusion 120 Front member (extrusion material) 121 Side 122 Bottom 123 Side 124 Top 125 Front engagement part 126 Front hook 127 Front protrusion 130 Rear member (extrusion material) 131 Side 132 Bottom 133 Side 134 Top 135 Rear engagement part 136 Rear hook 137 Rear protrusion 140 Cross member (extrusion material) 141 Side 142 Side 143 Top 144 Bottom 145 Opening 146 Cross protrusion 200 Resin material 210 Bottom wall 211 1st convex part 212 Second convex part 213 Protrusion 220 Perimeter Wall 221 Resin material engagement part 230 Flange wall

Claims

1. A frame in which a plurality of extrusion members are arranged in a frame shape; A resin material integrally molded with the frame; Equipped with The resin material is A bottom wall is disposed below the frame, and a bottom surface of the frame is embedded in the bottom wall; a peripheral wall disposed around the horizontal outside of the frame and having the horizontal outside side surface of the frame buried therein; The battery case for an automobile has the following features:

2. The plurality of extrusion materials include A pair of side members extending in the front-rear direction of the vehicle body; a cross member extending in the vehicle body width direction and connecting the pair of side members; The automotive battery case according to claim 1 ,

3. The automotive battery case according to claim 1 or 2, wherein at least one set of the plurality of extrusion members are welded to each other.

4. The automobile battery case according to claim 1 or 2, wherein at least one set of the plurality of extrusion members are fastened to each other by a bracket.

5. The resin material has a flange wall extending horizontally outward from the peripheral wall, 3. The automotive battery case according to claim 1, wherein a metal vehicle body joining member is embedded in the flange wall, enabling joining to the vehicle body.

6. 3. The automotive battery case according to claim 1, wherein a metal battery connecting member is embedded in the bottom wall to enable connection with a battery.

7. 3. The automobile battery case according to claim 1, wherein a metal bottom plate is embedded in the bottom wall.

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