Support device of drive battery

Abstract

To reduce an assembly tolerance of a bracket of a drive battery and inhibit damage to the drive battery.SOLUTION: A support device of a drive battery includes: a pair of front and rear brackets 7 disposed in a vehicle length direction of an electric vehicle and respectively having substantially U-shaped cross sections; and a pair of left and right brackets 8 disposed in a vehicle width direction and each formed by an upper member 80 and a lower member 90. The front and rear brackets 7 and the left and right brackets 8 cover a drive battery 4. The upper member 80 comprises: an upper surface part 81 overlapping with upper surfaces of the front and rear brackets 7; and an upper side surface part 82 disposed on a side of the drive battery 4. The lower member 90 comprises: a lower surface part 91 overlapping with lower surfaces of the front and rear brackets 7; and a lower side surface part 92 overlapping with the upper side surface part 82. The upper side surface part 82 includes a protruding part 83 protruding to the outer side in the vehicle width direction. A first fastening hole is provided on a top surface of the protruding part 83. A second fastening hole is provided at a position overlapping with the first fastening hole at the lower side surface part 92. One of the first fastening hole and the second fastening hole has a substantially oval shape elongated in a vehicle height direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a support device for a drive battery mounted in a vehicle. [Background technology]

[0002] Conventionally, from the viewpoint of reducing the burden on the environment, there has been progress in the development of electric vehicles, hybrid vehicles, fuel cell vehicles, and other small vehicles such as passenger cars that run on power supplied from a drive battery to a motor. Furthermore, in recent years, electric vehicles have also been developed in the field of large vehicles such as trucks (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-113063 A Summary of the Invention [Problem to be solved by the invention]

[0004] A drive battery installed in a large vehicle is generally attached to the frame of the vehicle using a bracket. This bracket may be made up of multiple members, and each member is fastened to each other and assembled with fastening members such as bolts.

[0005] On the other hand, it is possible that gaps may occur between parts due to assembly tolerances that arise from the accumulation of tolerances of each component. Even if this gap is within the allowable range, it may affect the fastening force of the fastening members. For this reason, it is desirable to reduce gaps caused by assembly tolerances as much as possible. Furthermore, when fastening members are used on the bracket, there is a risk that the fastening members may come into contact with the drive battery and cause damage to the drive battery when another vehicle crashes into the vehicle from the side, and it is desirable to be able to reduce such risks as well.

[0006] The present invention was devised with an eye on such problems, and its purpose is to provide a support device for a driving battery that can reduce the assembly tolerance of the bracket for the driving battery while suppressing damage to the driving battery. [Means for solving the problem]

[0007] The present invention has been made to solve at least part of the above problems, and can be realized in the following aspects or application examples. The support device for a driving battery in this application example is a support device for a driving battery mounted on an electric vehicle, and comprises a pair of front and rear brackets having an approximately U-shaped cross section and arranged on the front and rear sides, respectively, in the vehicle length direction of the electric vehicle, and a pair of left and right brackets consisting of an upper member and a lower member and arranged on the left and right sides, respectively, in the vehicle width direction of the electric vehicle, and the pair of front and rear brackets and the pair of left and right brackets cover the driving battery. The upper member consists of an upper surface portion that is positioned to overlap the upper surface portions of the front and rear brackets and an upper side portion that is positioned to the side of the driving battery, and the lower member consists of a lower surface portion that is positioned to overlap the lower surface portions of the front and rear brackets and a lower side portion that is positioned to overlap the upper side portion. One of the upper side portion and the lower side portion has a convex portion protruding outward in the vehicle width direction, and a first fastening hole is provided on a top surface of the convex portion, the other of the upper side portion and the lower side portion has a second fastening hole at a position overlapping with the first fastening hole, and one of the first fastening hole and the second fastening hole is approximately elliptical and elongated in the vehicle height direction.

[0008] According to this application example, one of the upper side portion and the lower side portion has a convex portion protruding outward in the vehicle width direction, and a first fastening hole is provided on the top surface of the convex portion, and the other of the upper side portion and the lower side portion has a second fastening hole provided at a position overlapping with the first fastening hole, so that the upper side portion and the lower side portion can be fastened with a fastening member through each fastening hole in the upper side portion and the lower side portion. In this case, since one of the first fastening hole and the second fastening hole has a generally elliptical shape that is long in the vehicle height direction, the relative positions of the upper side portion and the lower side portion can be adjusted to fasten them to each other. Therefore, when assembling the pair of left and right brackets to the pair of front and rear brackets, the vertical lengths of the left and right brackets can be adjusted relative to the vertical length of the front and rear brackets so that the tolerance approaches 0. As a result, the assembly tolerance of the brackets for the drive battery can be reduced. In addition, one of the upper side portion and the lower side portion has a convex portion that protrudes outward in the vehicle width direction and a first fastening hole is provided at the top surface of the convex portion, and the other of the upper side portion and the lower side portion has a second fastening hole at a position overlapping with the first fastening hole, so that the fastening member that fastens the upper side portion and the lower side portion can be positioned outward in the vehicle width direction. This reduces the risk of the fastening member coming into contact with the drive battery and causing damage to the drive battery when another vehicle crashes into the host vehicle. Effect of the Invention

[0009] According to the present invention, it is possible to reduce the assembly tolerance of the bracket for the drive battery while suppressing damage to the drive battery. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is an exploded perspective view showing a bracket for explaining the structure of a support device for a driving battery according to the embodiment. [Diagram 2] 2 is a perspective view showing a process of assembling a bracket of the driving battery support device shown in FIG. 1. [Diagram 3] 2 is a perspective view showing a process of assembling a bracket of the driving battery support device shown in FIG. 1. [Figure 4] 2 is a perspective view of the driving battery shown in FIG. 1 in a state where it is installed in a vehicle body. [Diagram 5] 2 is a cross-sectional view of the front and rear brackets and the left and right brackets of the driving battery support device shown in FIG. 1 in an assembled state. [Figure 6]6 is an enlarged cross-sectional view of a main portion showing an assembled state of the front and rear brackets and the left and right brackets shown in FIG. 5 (an enlarged view of part A in FIG. 5). [Figure 7] 7 is a cross-sectional view showing an upper member and a lower member before the left and right brackets shown in FIG. 6 are fastened to each other. [Figure 8] 7 is a cross-sectional view showing an upper member and a lower member after the left and right brackets shown in FIG. 6 are fastened to each other. [Figure 9] 4 is a cross-sectional view of the front and rear brackets and the left and right brackets in an assembled state, illustrating the effect of the driving battery support device shown in FIG. 1. FIG. [Figure 10] 6(a) and 6(b) are cross-sectional views of the front and rear brackets and the left and right brackets in an assembled state, illustrating the effect of reducing intersections due to the assembly structure of the front and rear brackets and the left and right brackets shown in FIG. 5. [Figure 11] 13 is a cross-sectional view illustrating the structure of a driving battery support device according to a first modified example, showing the assembled state of front and rear brackets and left and right brackets. FIG. [Figure 12] FIG. 11 is a perspective view illustrating the structure of a driving battery support device according to a second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The embodiments of the present invention will be described with reference to the drawings. The following embodiments are merely examples, and are not intended to exclude the application of various modifications and techniques not specified in the embodiments. The configurations of the following embodiments can be modified in various ways without departing from the spirit of the embodiments. In addition, they can be selected or combined as necessary.

[0012] [1. Configuration] [1-1. Overall composition] As shown in FIG. 4, a support device 1 for a driving battery according to this embodiment (also simply referred to as the support device 1) is mounted on an electric truck 3 equipped with a ladder frame 2 that forms the skeleton of the vehicle body. The electric truck 3 is an electric vehicle that runs by supplying power from a driving battery pack (also simply referred to as a "driving battery" or "battery pack") 4 to an electric motor (not shown). Electric vehicles include not only pure electric vehicles that are not equipped with an internal combustion engine, but also hybrid vehicles that are equipped with an internal combustion engine for driving source or power generation. The electric truck 3 is also referred to as an "electric vehicle 3" or a "vehicle 3".

[0013] Hereinafter, the front-rear direction of the electric truck 3 is also referred to as the vehicle length direction D1, and the left-right direction of the electric truck 3 is also referred to as the vehicle width direction D2. In addition, the up-down direction perpendicular to both the front-rear direction and the left-right direction is also referred to as the vehicle height direction D3. In the drawings, the front is indicated by "FR", the rear is indicated by "RR", the left is indicated by "LH", the right is indicated by "RH", the up is indicated by "UP", and the down is indicated by "DW". Note that FIG. 4 shows the lower structure of the electric truck 3, and the upper structure (body) arranged above the ladder frame 2 is omitted.

[0014] The ladder frame 2 is a structural member of the electric truck 3 and has high rigidity and strength. The ladder frame 2 includes a pair of side rails 21 extending in a vehicle length direction D1 and a plurality of cross members 22 extending in a vehicle width direction D2 and connecting the side rails 21 to each other. The pair of side rails 21 are disposed spaced apart from each other in the vehicle width direction D2. Each side rail 21 is formed in a channel shape (U-shaped cross section) having a plate-shaped web portion 21a extending along the vehicle length direction D1 and the vehicle height direction D3, and a pair of plate-shaped flange portions 21b, 21c extending inward in the vehicle width direction D2 from upper and lower edges of the web portion 21a. The multiple cross members 22 are disposed spaced apart from each other in the vehicle length direction D1. Here, two cross members 22 are illustrated, each disposed at two locations: a location overlapping with the battery pack 4 in the vehicle height direction D3, and a location rearward of the battery pack 4.

[0015] The battery pack 4 may be, for example, a general-purpose high-voltage battery pack used in passenger cars. In the electric truck 3, the battery pack 4 is mounted below a pair of side rails 21 and protrudes outward in the vehicle width direction D2 beyond each side rail 21. Here, a box-shaped battery pack 4 whose dimension in the vehicle height direction D3 is smaller (thinner) than each dimension in the vehicle length direction D1 and the vehicle width direction D2 is exemplified. However, the shape of the battery pack 4 is not particularly limited.

[0016] The battery pack 4 has a pair of battery side surfaces 41, 42 (see FIG. 1 ) that each face outward in the vehicle width direction D2. The pair of battery side surfaces 41, 42 are each located outward in the vehicle width direction D2 from the pair of side rails 21. More specifically, the right battery side surface 41 is located to the right of the right side rail 21, and the left battery side surface 42 is located to the left of the left side rail 21.

[0017] As described above, the battery side surfaces 41, 42 of the battery pack 4 are disposed outside the side rails 21 in the vehicle width direction D2, so that the dimension in the vehicle width direction D2 is ensured to be larger than the distance between the web portions 21a of the side rails 21. This allows the battery pack 4 to have a large capacity. In addition, in order to ensure the cruising distance of the electric truck 3, it is preferable that the battery pack 4 is disposed over a wide range between the front and rear wheel axles. In a relatively small electric truck 3 (one with a relatively short wheelbase), one battery pack 4 can be disposed over almost the entire area of ​​the wheelbase. In this case, the front wheels are disposed in close proximity to the front of the battery pack 4, and the rear wheels are disposed in close proximity to the rear of the battery pack 4.

[0018] The size of the electric truck 3 and the number of battery packs 4 are not limited to the example of this embodiment. In a relatively large electric truck 3 (having a relatively long wheelbase), multiple battery packs 4 may be arranged side by side in the vehicle length direction D1. In this case, too, by arranging multiple battery packs 4 over a wide range of the wheelbase, the overall capacity of the battery packs 4 can be increased, and the cruising distance can be ensured.

[0019] The support device 1 connects the battery pack 4 to the side rails 21 and supports the battery pack 4. In other words, the battery pack 4 is supported by the side rails 21 via the support device 1. In this embodiment, a support device 1 that is configured to be symmetrical (plane symmetrical) with respect to a vertical plane that passes through the center in the vehicle width direction D2 and extends in the vehicle length direction D1 is shown as an example.

[0020] 4, the support device 1 includes a battery-side bracket 5 that houses the battery pack 4, and a frame-side bracket (connecting bracket) 6 that connects the battery-side bracket 5 and the side rail 21. The battery-side bracket 5 is an outer wall body that is disposed on the outer periphery of the battery pack 4, and has the function of protecting the battery pack 4 from impact loads. On the other hand, the frame-side bracket 6 extends outward and downward from the side rail 21 in the vehicle width direction D2, and has the function of suspending the battery pack 4 housed in the battery-side bracket 5 from the side rail 21.

[0021] As shown in FIG. 1, the battery side bracket 5 of this embodiment has a main bracket (front bracket) 7F, a main bracket (rear bracket) 7R, an end cross member (right bracket) 8R, and an end cross member (left bracket) 8L. The main bracket (front bracket) 7F is disposed on the front side of the electric truck 3 in the vehicle length direction D1 so as to cover the front edge portion 40FR of the battery pack 4. The main bracket (rear bracket) 7R is disposed on the rear side of the electric truck 3 in the vehicle length direction D1 so as to cover the rear edge portion 40RR of the battery pack 4. The end cross member (right bracket) 8R is disposed on the right side in the vehicle width direction D2 of the electric truck 3 so as to cover the right edge portion 40RH of the battery pack 4. The end cross member (left bracket) 8L is disposed on the left side in the vehicle width direction D2 of the electric truck 3 so as to cover the left edge portion 40LH of the battery pack 4.

[0022] The pair of main brackets 7F, 7R are symmetrical to each other and have the same shape, and when there is no need to distinguish between them, they are also referred to as main bracket 7 or bracket 7. In addition, the pair of main brackets 7F, 7R are also collectively referred to as front and rear brackets 7F, 7R. The pair of end cross members 8R, 8L are also symmetrical to each other and have the same shape, and when there is no need to distinguish between them, they are simply referred to as end cross members 8, side edge brackets 8, or brackets 8. In addition, the pair of end cross members 8R, 8L are collectively referred to as left and right brackets 8R, 8L. The pair of main brackets 7F, 7R and the pair of end cross members 8R, 8L cover the front, rear, left and right sides of the battery pack 4.

[0023] The pair of main brackets 7F, 7R are generally symmetrical with respect to a vertical plane that passes through the center in the vehicle width direction D2 and extends in the vehicle length direction D1. The main brackets 7F, 7R are also symmetrical with respect to each other. The schematic shapes of the pair of end cross members 8R, 8L are also formed to be symmetrical with respect to each other in the front-rear direction with respect to a vertical plane that passes through the center in the vehicle length direction D1 and extends in the vehicle width direction D2. The end cross members 8R, 8L are also formed to be plane-symmetrical with each other.

[0024] In this embodiment, each of the main brackets 7F, 7R and each of the end cross members 8R, 8L are formed of steel plates. The main brackets 7F, 7R are formed in a channel shape having a substantially U-shaped cross section. The end cross members 8R, 8L are formed by fastening two members, and are formed in a channel shape having a unique shape in one part, which will be described later. The battery side bracket 5 is disposed so as to surround the four sides of the battery pack 4 by the main brackets 7F, 7R and the end cross members 8R, 8L.

[0025] In this embodiment, high tensile steel is used as the material for each of the main brackets 7F, 7R and each of the end cross members 8R, 8L (i.e., the battery side bracket 5). High tensile steel plate is a steel material defined as having a tensile strength of, for example, 490 MPa or more and less than 980 MPa (or less than 1000 MPa), but has the advantages of being thin-walled and corrosion-resistant. By using this, the battery side bracket 5, and in turn the support device 1, can be made lighter while increasing the load-bearing strength. The load-bearing strength required for the support device 1 is a strength that does not deform to the extent that it damages the case of the battery pack 4, even if the support device 1 receives a certain collision load when the vehicle 3 is hit in a side collision, front collision, or rear collision.

[0026] However, the material of the battery side bracket 5 is not limited to this, and other steel materials or materials other than steel materials may be applied. If a steel material with higher tensile strength is used, for example ultra-high tensile steel defined as having a tensile strength of 980 MPa or more (or 1000 MPa or more), further weight reduction can be achieved, but currently, ultra-high tensile steel is more difficult to process than high tensile steel and also leads to increased costs, so in this embodiment, high tensile steel is used.

[0027] Each of the main brackets 7F, 7R and each of the end cross members 8R, 8L are channel shaped. Each of the main brackets 7 has a web portion 7a, an upper flange portion (upper surface portion) 7b, and a lower flange portion (lower surface portion) 7c. Each of the end cross members 8 has a web portion 8a, an upper flange portion (upper surface portion) 8b, and a lower flange portion (lower surface portion) 8c.

[0028] The main bracket 7F is disposed so as to cover the front edge portion 40FR of the battery pack 4. In other words, the main bracket 7F is disposed such that the web portion 7a is along the front surface 43 of the battery pack 4, the upper flange portion 7b is along the portion of the upper surface 45 of the battery pack 4 closer to the front surface, and the lower flange portion 7c is along the portion of the lower surface 46 of the battery pack 4 closer to the front surface.

[0029] The main bracket 7R is disposed so as to cover the rear edge portion 40RR of the battery pack 4. In other words, the main bracket 7R is disposed such that the web portion 7a is aligned along the rear surface 44 of the battery pack 4, the upper flange portion 7b is aligned along the portion of the upper surface 45 of the battery pack 4 closer to the rear, and the lower flange portion 7c is aligned along the portion of the lower surface 46 of the battery pack 4 closer to the rear.

[0030] The right end cross member 8R is disposed so as to cover the right edge portion 40RH of the battery pack 4. That is, the end cross member 8R is disposed such that the web portion 8a runs along the right side surface 41 of the battery pack 4, the upper flange portion 8b runs along the portion of the upper surface 45 of the battery pack 4 closer to the right side, and the lower flange portion 8c runs along the portion of the lower surface 46 of the battery pack 4 closer to the right side.

[0031] The left end cross member 8L is disposed so as to cover the left edge portion 40LH of the battery pack 4. That is, the end cross member 8L is disposed such that the web portion 8a runs along the left side surface 42 of the battery pack 4, the upper flange portion 8b runs along the portion of the upper surface 45 of the battery pack 4 closer to the left side, and the lower flange portion 8c runs along the portion of the lower surface 46 of the battery pack 4 closer to the left side.

[0032] 2, the main bracket 7 is placed in advance at the front edge portion 40FR and the rear edge portion 40RR of the battery pack 4, and then the end cross member 8 is placed at the right edge portion 40RH and the left edge portion 40LH of the battery pack 4, and the main bracket 7 and the end cross member 8 are connected to the battery pack 4. Therefore, the flange portions 7b, 7c of the bracket 7 are placed closer to the battery pack 4 (inside in the vehicle height direction D3) than the flange portions 8b, 8c of the end cross member 8.

[0033] As a result, both ends of the flanges 7b, 7c of the main bracket 7 overlap with both ends of the flanges 8b, 8c of the end cross member 8. The main bracket 7 and the end cross member 8 are joined to each other at this overlapping portion (overlapped portion) 51 (see FIG. 3). In this embodiment, the main bracket 7 and the end cross member 8 are joined to each other using fastening members such as bolts (not shown) by utilizing the multiple fastening holes 70 shown in FIG. 1. Here, the fastening holes 70 are arranged in a triangular shape in a set of three, but this number is not limited. Furthermore, the joining means is not limited thereto, and the joining may be performed using any fixing device or any joining means (welding, adhesive, etc.).

[0034] Further, the end cross member 8 is disposed such that its web portion 8a is spaced (with a gap) from the side surfaces 41, 42 of the battery pack 4 (see FIG. 5), thereby ensuring a deformation allowance (an allowance for absorbing an impact load) during a collision. This deformation allowance is ensured according to the expected amount of deformation, but if no deformation allowance is required, the web portion 8a of the end cross member 8 may be disposed so as to come into contact with the side surfaces 41, 42 of the battery pack 4.

[0035] As shown in FIG. 3, the lower part of the frame side bracket 6 is fixed to the upper part of the overlapping part 51 where the upper flange parts 7b, 8b of the main bracket 7 and the end cross member 8 are overlapped and joined. Also, as shown in FIG. 4, the frame side bracket 6 is fixed to the web part 21a of the side rail 21. Therefore, two frame side brackets 6 are provided on each side of the electric truck 3 (outside the vehicle width direction D2 of each side rail 21) (four in total). Note that the part where the upper flange part 7b of the main bracket 7, the upper flange part 8b of the end cross member 8, and the lower part of the frame side bracket 6 are connected is called a connecting part (not shown). Note that the connecting part is an abutting surface between the lower part of the frame side bracket 6 and the upper flange part 8b of the end cross member 8, and is the entire lower surface of the frame side bracket 6 or a main part of the lower surface, and is an area located inside the overlapping part 51.

[0036] [1-2. Bracket structure] As shown in FIG. 1, in the present supporting device 1, the end cross members 8 are formed in a specific shape. That is, as shown in Figs. 5 and 6, the end cross members 8 each include an upper member 80 disposed above and a lower member 90 disposed below. In the following description, attention will be focused on the end cross member 8L on the left side in the vehicle width direction, but the end cross member 8R on the right side in the vehicle width direction is configured in the same manner.

[0037] 6, the upper member 80 is composed of an upper surface portion 81 arranged so as to overlap with the upper flange portion 7b forming the upper surface of the main bracket 7, and an upper side surface portion 82 arranged on the side of the battery pack 4. The upper side surface portion 82 has a protrusion 83 that protrudes outward in the vehicle width direction D2. The protrusion 83 protrudes outward in the vehicle width direction D2 in a ridge shape that extends continuously in the vehicle length direction D1.

[0038] The lower member 90 is composed of a lower surface portion 91 arranged to overlap the lower flange portion 7c forming the lower surface of the main bracket 7, and a lower side surface portion 92 arranged on the side of the battery pack 4. The lower side surface portion 92 has a protrusion 93 that protrudes outward in the vehicle width direction D2. The protrusion 93 also protrudes outward in the vehicle width direction D2 in a ridge shape that extends continuously in the vehicle length direction D1.

[0039] In addition, the upper surface portion 81 of the upper member 80 constitutes the upper flange portion 8b (see Figure 1) of the end cross member 8, the lower surface portion 91 of the lower member 90 constitutes the lower flange portion 8c (see Figure 1) of the end cross member 8, and the upper side portion 82 of the upper member 80 and the lower side portion 92 of the lower member 90 constitute the web portion 8a (see Figure 1) of the end cross member 8.

[0040] In other words, the upper side portion 82 comprises a first base surface portion 84 extending vertically downward from the outer edge of the top surface portion 81 in the vehicle width direction D2, and a second base surface portion 85 spaced downward from the first base surface portion 84 and extending vertically downward at the same vehicle width position as the first base surface portion 84, and a convex portion 83 is formed between the first base surface portion 84 and the second base surface portion 85 in the vertical direction, protruding outward in the vehicle width direction D2.

[0041] The convex portion 83 is composed of a first inclined surface portion 86 bent obliquely downward from the lower end edge of the first base surface portion 84 toward the outside in the vehicle width direction D2, a top surface portion (top surface) 88 bent vertically downward from the lower end edge of the first inclined surface portion 86, and a second inclined surface portion 87 bent obliquely downward from the lower end edge of the top surface portion 88 toward the inside in the vehicle width direction D2. The second base surface portion 85 is bent vertically downward from the lower end edge of the second inclined surface portion 87. The top surface portion 88 has a plurality of fastening holes (first fastening holes) 89 (see FIG. 7) arranged side by side in the vehicle length direction D1.

[0042] The lower side portion 92 has a base surface portion 95 extending vertically upward from the outer edge of the lower surface portion 91 in the vehicle width direction D2, and a convex portion 93 is formed by protruding outward from the upper edge of the base surface portion 95 in the vehicle width direction D2. The convex portion 93 is composed of an inclined surface portion 97 corresponding to the second inclined surface portion 87 of the convex portion 83 , and a top surface portion (top surface) 98 corresponding to the top surface portion 88 of the convex portion 83 .

[0043] In addition, in this embodiment, the inner surface (the inner surface in the vehicle width direction D2) of the lower side portion 92 is formed so as to overlap with the outer surface (the outer surface in the vehicle width direction D2) of the upper side portion 82 from the outside (the outside in the vehicle width direction D2). Furthermore, in this embodiment, the upper surface portion 81 of the upper member 80 is positioned so as to overlap the upper flange portion 7b of the main bracket 7 from above, and the lower surface portion 91 of the lower member 90 is also positioned so as to overlap the lower flange portion 7c of the main bracket 7 from above.

[0044] In other words, the inclined surface portion 97 is bent obliquely upward from the upper edge of the base surface portion 95 toward the outside in the vehicle width direction D2, and the top surface portion 98 is bent vertically upward from the upper edge of the inclined surface portion 97. A plurality of fastening holes (second fastening holes) 99 (see FIG. 7) are also provided in the top surface portion 98 aligned in the vehicle length direction D1. The fastening holes 99 in the top surface portion 98 are arranged at positions overlapping with the fastening holes 89 in the top surface portion 88.

[0045] At least one of the first fastening hole 89 and the second fastening hole 99 is a generally elliptical shape that is long in the vehicle height direction D3. The generally elliptical shape includes an elliptical shape and an oval shape. In this embodiment, as shown in Fig. 7, only one of the first fastening hole 89 and the second fastening hole 99 (here, the second fastening hole 99) is generally elliptical, and the other (the first fastening hole 89) is circular, which is relatively easy to process. Of course, both the first fastening hole 89 and the second fastening hole 99 may be generally elliptical.

[0046] 7, the upper member 80 and the lower member 90 are fastened to each other by overlapping the lower member 90 from the outside of the upper member 80 (outside in the vehicle width direction D2), aligning the fastening holes 89, 99, and then inserting fastening members 100 such as bolts. As a result, the upper member 80 and the lower member 90 are integrated to form the end cross member 8, as shown in FIG.

[0047] In this embodiment, the fastening holes 89, 99 are arranged in only one row in the vehicle length direction D1, but may be arranged in two or more rows in the vehicle length direction D1. In addition, in this embodiment, the fastening holes 89, 99 are spaced apart from each other by a predetermined constant distance, but this space may be set appropriately. In addition, in this embodiment, high-tensile steel similar to that used for the main bracket 7, etc. is used for both the upper member 80 and the lower member 90 of each end cross member 8, but the materials used for the upper member 80 and the lower member 90 are not limited to this.

[0048] [2. Actions and Effects] Since the support device 1 for the driving battery 4 according to this embodiment is configured as described above, the following actions and effects are obtained.

[0049] One of the first fastening hole 89 and the second fastening hole 99 is approximately elliptical and elongated in the vehicle height direction D3, so that when fastening the upper member 80 and the lower member 90 with a fastening member 100 such as a bolt, the approximately elliptical first fastening hole 89 or second fastening hole 99 can be used to adjust the distance between the upper surface portion 81 of the upper member 80 and the lower surface portion 91 of the lower member 90 to correspond to the distance between the upper flange portion 7b and the lower flange portion 7c of the main bracket 7.

[0050] Therefore, it is possible to eliminate or reduce the gap between the upper surface portion 81 of the upper member 80 and the upper flange portion 7b of the main bracket 7, and the gap between the lower surface portion 91 of the lower member 90 and the lower flange portion 7c of the main bracket 7, which are overlapped with each other, making it easier to maintain the fastening force of the fastening member 100. As a result, it is possible to improve the supporting rigidity and supporting strength of the battery pack 4 by this supporting device 1.

[0051] Further, the fastening holes 89, 99 into which the fastening members 100 are inserted to join the upper member 80 and the lower member 90 of the end cross member 8 are provided in the top surface portions 88, 98 of the convex portions 83, 93 protruding outward in the vehicle width direction D2, so that the fastening members 100 after fastening can be disposed outward in the vehicle width direction D2. As a result, the fastening members 100 can be separated outward from the battery pack 4 in the vehicle width direction D2, and when another vehicle collides with the host vehicle from the side, the fastening members 100 deform within the gap as shown by the two-dot chain line in Fig. 9, reducing the risk of the fastening members 100 coming into contact with the battery pack 4 and causing damage to the battery pack 4.

[0052] Furthermore, in this embodiment, as shown in a simplified manner in FIG. 10(a), the upper surface portion 81 of the upper member 80 overlaps from above with the upper flange portion 7b of the main bracket 7, and the lower surface portion 91 of the lower member 90 also overlaps from above with the lower flange portion 7c of the main bracket 7, thereby suppressing the accumulation of component tolerances and contributing to reducing the assembly tolerance of the battery side bracket 5 of the battery pack 4. In other words, there are various ways in which the upper surface portion 81 of the upper member 80 overlaps with the upper flange portion 7b of the main bracket 7, and the lower surface portion 91 of the lower member 90 overlaps with the lower flange portion 7c of the main bracket 7.

[0053] For example, when the end cross member 8 is placed over the ends of the front and rear main brackets 7F, 7R in the vehicle width direction D2 and fastened and fixed using fastening members such as bolts, a possible configuration is to overlap the upper surface portion 81 of the upper member 80 with the upper flange portion 7b of the main bracket 7 from above, and to overlap the lower surface portion 91 of the lower member 90 with the lower flange portion 7c of the main bracket 7 from below, as shown in a simplified manner in Fig. 10(b). In this case, the tolerance d1 of the distance between the upper flange portion 7b and the lower flange portion 7c of the main brackets 7F, 7R and the tolerance d2 of the distance between the upper surface portion 81 and the lower surface portion 91 of the end cross member 8 are accumulated, and the assembly tolerance is d1 + d2.

[0054] In this embodiment, the upper surface portion 81 of the upper member 80 overlaps from above with the upper flange portion 7b of the main bracket 7, and the lower surface portion 91 of the lower member 90 overlaps from above with the lower flange portion 7c of the main bracket 7, so that the tolerances d1, d2 are not cumulative, and the assembly tolerance is the larger of d1, d2. Therefore, this structure contributes to reducing the assembly tolerance of the battery-side bracket 5 of the battery pack 4.

[0055] In this embodiment, both the upper member 80 and the lower member 90 of the end cross member 8 are made of high tensile steel, but the material of the end cross member 8 is not limited to this. For example, an iron-based material or other steel material such as ultra-high tensile steel may be used, an aluminum-based material, a carbon material, a resin material, or a fiber-reinforced material (fiber-reinforced resin, fiber-reinforced metal, etc.) may be used.

[0056] For example, as shown in Fig. 11, an end cross member 8A may be constructed by forming parts 80P, 90P of an upper member 80A and a lower member 90A from a non-metallic material such as resin, and forming the other parts from a metallic material, and joining them together. In this case, the impact absorbing properties of the resin or the like can be utilized, and the protection performance of the battery pack 4 in the event of a side collision can be improved.

[0057] In addition, in this embodiment, the convex portions 83, 93 protrude outward in the vehicle width direction D2 in a ridge shape that extends continuously in the vehicle length direction D1, but the convex portions are not limited to this as long as they protrude outward in the vehicle width direction D2. For example, as in the end cross member 8B shown in Fig. 12, a plurality of convex portions 83B, 93B protruding outward in the vehicle width direction D2 in a cone shape may be intermittently formed in the upper member 80A and the lower member 90A in the vehicle length direction D1, and fastening holes (not shown) may be formed in each of the convex portions 83B, 93B.

[0058] [3.Other] The configuration of the above embodiment is merely an example, and can be modified appropriately without departing from the spirit and scope of the present invention. For example, in the above embodiment, an example has been described in which the drive battery support device 1 is applied to the electric truck 3, but the drive battery support device of the present invention may be applied to electric vehicles other than trucks. Furthermore, in the above embodiment, the support device for the driving battery is connected to the side rail 21 and supported by the side rail 21, but it may also be connected to a structural element of the vehicle other than the side rail 21 and supported thereon.

[0059] In addition, in the above embodiment, each end cross member 8 is formed symmetrically with respect to each other in the front-to-rear direction with respect to a vertical plane that passes through the center of the vehicle length direction D1 and extends in the vehicle width direction D2 as the plane of symmetry, but is not limited to a front-to-rear symmetric shape. In addition, in the above embodiment, the first base surface portion 84 and the second base surface portion 85 of the upper side portion 82 are positioned at the same vehicle width direction position, but these do not necessarily have to be positioned at the same vehicle width direction position.

[0060] Furthermore, in the above embodiment, the upper surface portion 81 of the upper member 80 overlaps from above with the upper flange portion 7b of the main bracket 7, and the lower surface portion 91 of the lower member 90 also overlaps from above with the lower flange portion 7c of the main bracket 7, which contributes to reducing assembly tolerances, but the overlapping pattern is not limited to this. For example, even if the upper surface 81 of the upper member 80 overlaps the upper flange portion 7b of the main bracket 7 from below, and the lower surface 91 of the lower member 90 overlaps the lower flange portion 7c of the main bracket 7 from below, this contributes to reducing assembly tolerances. Further, other overlapping patterns are also applicable, although they do not contribute to reducing assembly tolerances. [Explanation of symbols]

[0061] 1. Drive battery support device (support device) 2 Ladder frame 3 Electric truck (electric vehicle, vehicle) 4 Drive battery pack (drive battery, battery pack) 5 Battery side bracket 6 Frame side bracket (connecting bracket) 7F,7 Main bracket (front bracket) 7R,7 Main bracket (rear bracket) 7a Web part of main bracket 7 7b Upper flange portion (upper surface portion) of main bracket 7 7c Lower flange part (lower surface part) of main bracket 7 8R,8 End cross member (right bracket) 8L,8 End cross member (left bracket) 8a Web part of end cross member 8 8b Upper flange part (top surface) 8c Lower flange part (lower surface part) 21 Side rail 21a Web portion of side rail 21 21b, 21c Flange portion of side rail 21 22 Cross member 40FR Battery pack 4 front edge 40RR Battery pack 4 rear edge 40RH Right edge of battery pack 4 40LH Left edge of battery pack 4 41 Right side of battery 4 42 Left side of battery 4 43 Front of battery pack 4 44 Rear of battery pack 4 45 Top of battery pack 4 46 Underside of battery pack 4 50 Connection part 51 Polymerization section 70 Fastening hole 80 Upper member 81 Top part 82 Upper side part 83 Convex 84 First base part 85 Second base part 86 First slope section 87 Second slope section 88 Top part (Top surface) 89 Fastening hole (first fastening hole) 90 Lower member 91 Bottom surface 92 Lower side surface 93 Protrusion 94 Base surface 97 Inclined surface 98 Top surface 99 Fastening hole (second fastening hole) 100 Fastening member D1 Vehicle length direction D2 Vehicle width direction D3 Vehicle height direction FR Front RR Rear LH Left RH Right UP Upward DW Downward

Claims

[Claim 1] A support device for a drive battery mounted on an electric vehicle, comprising: A pair of front and rear brackets each having a substantially U-shaped cross section and disposed at a front side and a rear side in a vehicle length direction of the electric vehicle, a pair of left and right brackets each composed of an upper member and a lower member, the left and right brackets being disposed on the left and right sides, respectively, in a vehicle width direction of the electric vehicle; the pair of front and rear brackets and the pair of left and right brackets cover the driving battery, the upper member includes an upper surface portion disposed to overlap the upper surface portions of the front and rear brackets and an upper side surface portion disposed to the side of the driving battery, the lower member includes a lower surface portion disposed to overlap the lower surface portion of the front and rear brackets, and a lower side surface portion disposed to overlap the upper side surface portion, One of the upper side portion and the lower side portion has a convex portion protruding outward in the vehicle width direction, and a first fastening hole is provided on a top surface of the convex portion, A second fastening hole is provided in the other of the upper side portion and the lower side portion at a position overlapping with the first fastening hole, One of the first fastening hole and the second fastening hole is substantially elliptical in the vehicle height direction. A support device for a driving battery comprising:

Images