Side structure of electric vehicle

Abstract

This protects the battery pack, which is installed on the lower side of the floor, from impact loads. [Solution] The side structure of the electric vehicle is located outside the battery pack 10 and includes a body frame 20, 30 extending in the front-rear direction, a side sill 40 positioned at a distance from the body frame 20, 30 and extending in the front-rear direction, and a reinforcement 60 connecting the lower part of the side sill 40 to the body frame 20, 30. The rigidity of the reinforcement 60 in the width direction is set lower than the rigidity of the body frame 20, 30 in the width direction.

Description

Technical Field

[0001] The present invention relates to a side structure of an electric vehicle.

Background Art

[0002] An electric vehicle has a battery pack disposed below a floor panel that constitutes a floor portion of the vehicle, as disclosed in, for example, Patent Document 1. Also, in this example, a driving electric motor is disposed on the vehicle front side of the battery pack.

[0003] In addition, in order to extend the cruising range of an electric vehicle, the battery pack is required to have a larger capacity. As a result, the battery pack tends to become larger. Along with the increase in the size of the battery pack, the proportion of the space below the floor portion occupied by the battery pack increases.

[0004] Also, in an electric vehicle, it is necessary to secure a space for disposing the battery pack below the floor panel. In the structure of the above example, the floor panel is disposed above side members disposed on both sides in the vehicle width direction. The battery pack is disposed below the floor panel and between the side members on both sides.

[0005] The side members in the above example are members for securing vehicle body rigidity, and for example, strength capable of withstanding an impact load acting on the vehicle body due to a side collision, a front collision, etc. is required. In order to set the dimension of the battery pack in the vehicle width direction as large as possible, the outer portion of the battery pack in the vehicle width direction and the inner portion of the side member in the vehicle width direction are arranged to be closer to each other.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The sides of the underside of the vehicle body must have a certain level of strength against impact loads such as side collisions, and these sides must be equipped with a structure that absorbs the impact caused by such impacts. For example, the structure that absorbs the impact load absorbs the impact load by deforming the side of the vehicle body. Therefore, the side of the vehicle body must be provided with a stroke for deformation.

[0008] However, when attempting to provide an impact-absorbing structure on the outer side in the vehicle width direction of a highly rigid side member, the structure in the above example has limited space on the outer side of the side member in the vehicle width direction, making it difficult to secure sufficient stroke for the side of the vehicle body to deform in order to absorb the impact. Therefore, in the structure in the above example, there was room for improvement in effectively absorbing impact loads from side collisions, etc., in the space on the outer side of the battery pack in the vehicle width direction at the lower side of the vehicle body.

[0009] The present invention was made to solve the above problems, and its objective is to provide a side structure for an electric vehicle that can install a battery pack in a limited space below the vehicle floor and protect the battery pack from impact loads. [Means for solving the problem]

[0010] To achieve the above objective, the side structure of an electric vehicle according to the present invention comprises a battery pack disposed on the lower side of the floor portion of the vehicle, a vehicle body frame disposed on the lower side of the floor portion and on the outside in the vehicle width direction of the battery pack and extending in the vehicle longitudinal direction, and a side sill disposed at a distance on the outside in the vehicle width direction of the vehicle body frame and extending in the vehicle longitudinal direction. The side structure of the electric vehicle has a reinforcement connecting the lower part of the side sill and the vehicle body frame, and the rigidity of the reinforcement in the vehicle width direction is set lower than the rigidity of the vehicle body frame in the vehicle width direction. [Effects of the Invention]

[0011] According to the present invention, a battery pack can be installed in the limited space below the vehicle floor and protected from impact loads. [Brief explanation of the drawing]

[0012] [Figure 1] This is a perspective view of the side structure of the electric vehicle according to the present invention, as seen from above the floor portion of the electric vehicle. [Figure 2] Figure 1 is a perspective view of the left side of the electric vehicle with the side body outer panel attached, seen from below the vehicle. [Figure 3] Figure 1 is a bottom view of the side structure of the electric vehicle, as seen from below the vehicle. [Figure 4] Figure 3 is an enlarged perspective view of the battery mount member and battery suspension bracket, etc., as seen from the underside of the vehicle. [Figure 5] This is an enlarged bottom view showing the battery pack removed from Figure 3. [Figure 6] Figure 3 is a perspective view of section AA as seen from the rear of the vehicle. [Figure 7] Figure 5 is an end view taken along the BB arrow, with the battery pack and battery suspension bracket added for clarity. [Figure 8] Figure 5 is a cross-sectional view taken along the BB arrow, with the battery suspension bracket added for illustration. [Modes for carrying out the invention]

[0013] Hereinafter, one embodiment of the side structure of the electric vehicle according to the present invention will be described with reference to the drawings (Figures 1 to 8). In the figures, the direction of arrow Fr indicates the front in the longitudinal direction of the vehicle. In the description of the embodiment, "front (front end) and rear (rear end)" correspond to the front and rear of the vehicle in the longitudinal direction. Also, arrows R and L indicate the right and left sides when the occupant is looking forward of the vehicle. Also, arrow U indicates the upward direction in the vertical direction of the vehicle.

[0014] As shown in Figures 2 to 4, the side structure of the electric vehicle in this embodiment has a battery pack 10 located below the floor. Furthermore, as shown in Figure 3, the side structure includes a vehicle frame, a side sill 40, a reinforcement 60, and a cross member. In this embodiment, the reinforcement 60 connects the lower part of the side sill 40 to the vehicle frame that constitutes the vehicle body structure, and the rigidity of the reinforcement 60 in the vehicle width direction is set lower than the rigidity of the vehicle frame in the vehicle width direction. The members constituting the side structure of this embodiment will be described below.

[0015] As shown in Figures 1 and 3, the battery pack 10 is a heavy object located below the floor panel 17 that constitutes the floor of the vehicle. A detailed explanation of the structure of the battery pack 10 will be omitted, but the external shape of the battery pack 10 is roughly rectangular, and it has a top surface 11, left and right side walls 12, a bottom surface 13, a front wall 14, and a rear wall 15 (Figures 3 and 4). The battery pack 10 is suspended from a vehicle body component such as a side member 20, for example, via a battery mount member 30 and a battery suspension bracket 35. The configuration in which the battery pack 10 is attached will be explained later.

[0016] The vehicle body frame in this embodiment is a member positioned below the floor portion, on the outside in the vehicle width direction of the battery pack 10, and extending in the vehicle's longitudinal direction. The vehicle body frame is a highly rigid member formed from a metal material. The vehicle body frame in this embodiment includes a side member 20 and a battery mount member 30.

[0017] The side member 20 is a highly rigid member that constitutes the vehicle body skeleton and is formed of a metal material. As shown in FIG. 3, the side members 20 are arranged in a pair on both outer sides in the vehicle width direction at the lower part of the vehicle and extend in the vehicle longitudinal direction. In this example, they are arranged along the side wall portions 12 of the battery pack 10 with a space therebetween on the outer sides in the vehicle width direction of the left and right side wall portions 12 of the battery pack 10. In the vehicle longitudinal direction, the front portion of the side member 20 is arranged on the front side of the vehicle with respect to the front wall portion 14 of the battery pack 10, and the rear portion of the side member 20 is arranged on the rear side of the vehicle with respect to the rear wall portion 15 of the battery pack 10.

[0018] As shown in FIGS. 6 to 8, the side member 20 has a U-shaped cross-sectional shape that opens upward in the vehicle. That is, the side member 20 has an inner wall portion 21, an outer wall portion 22, and a bottom surface portion 23. The bottom surface portion 23 has a substantially rectangular horizontal plane that extends in the vehicle longitudinal direction. The inner wall portion 21 projects upward from the inner end in the vehicle width direction of the bottom surface portion 23 and extends in the vehicle longitudinal direction. An inner flange portion 21a that projects inward in the vehicle width direction is provided at the upper end of the inner wall portion 21. The outer wall portion 22 projects upward from the outer end in the vehicle width direction of the bottom surface portion 23 and extends in the vehicle longitudinal direction. An outer flange portion 22a that projects outward in the vehicle width direction is provided at the upper end of the outer wall portion 22. The inner flange portion 21a and the outer flange portion 22a are joined to the lower surface of the floor panel 17 by spot welding.

[0019] Also, in this embodiment, as shown in FIG. 6, an upper reinforcing plate 25 and a lower reinforcing plate 26 are provided inside the side member 20. The upper reinforcing plate 25 has a flat portion 25a extending in the vehicle front-rear direction and flange portions 25b protruding upward from both ends in the vehicle width direction of the flat portion 25a. The flange portions 25b on both sides are joined to the inner wall portion 21 and the outer wall portion 22 of the side member 20, respectively. The flat portion 25a of the upper reinforcing plate 25 is arranged at a distance below the floor panel 17. The lower reinforcing plate 26 has a flat portion 26a and flange portions 26b, similar to the upper reinforcing plate 25a, as shown in FIGS. 6 to 8. The flat portion 26a of the lower reinforcing plate 26 is joined to the bottom surface portion 23 of the side member 20. Also, the flange portions 26b of the lower reinforcing plate 26 are joined to the inner wall portion 21 and the outer wall portion 22 of the side member 20.

[0020] Subsequently, the cross members will be described. The cross members 71, 75 are members with high rigidity that constitute the vehicle body skeleton and are formed of a metal material. The cross members 71, 75 in this embodiment have a first cross member 71 and a second cross member 7, which is arranged on the vehicle rear side of the first cross member 71. Note that the cross members 71, 75 are not limited to the first cross member 71 and the second cross member 75.

[0021] As shown in FIG. 5, the first cross member 71 has a first center member 72 and a first extension member 73. The first center member 72 is a member extending in the vehicle width direction and has a U-shaped cross section that opens upward. Also, front flange portions 72f and rear flange portions 72r are provided at the upper ends of the front portion and the rear portion of the first center member 72, respectively. The front flange portions 72f and the rear flange portions 72r are joined to the lower surface of the floor panel 17 by spot welding.

[0022] The first extension member 73 is a member that extends outward in the vehicle width direction from the outer part in the vehicle width direction of the first central member 72. The outer part of the first central member 72 and the inner part of the first extension member 73 may be joined by, for example, spot welding. Also, as shown in Figures 7 and 8, the lower surface portion 73a of the first extension member 73 is inclined downward from the middle part in the vehicle width direction as it extends outward in the vehicle width direction. In addition, a vertical flange portion 73b that protrudes upward from the vehicle is provided at the outer end in the vehicle width direction of the lower surface portion 73a. The vertical flange portion 73b is joined to the inner wall portion 21 of the side member 20 by spot welding. Also, as shown in Figure 5, a flange 31a provided on the battery mount member 30, which will be described later, is joined to the outer part in the vehicle width direction of the lower surface portion 73a by spot welding.

[0023] Although not shown in the diagram, the front wall of the first extension member 73 has a flange portion that protrudes forward at its vehicle width-direction end, and the rear wall has a flange portion that protrudes rearward at its vehicle width-direction end. These flange portions are joined to the inner wall portion 21 of the side member 20 by spot welding, similar to the vertical flange portion 73b.

[0024] Furthermore, as shown in Figure 5, the first extension member 73, like the first central member 72, has a U-shaped cross-section that opens upward, and a front flange portion 73f and a rear flange portion 73r are provided at the upper ends of the front and rear portions, respectively. The front flange portion 73f and the rear flange portion 73r are joined to the inner flange portion 21a of the side member 20 by spot welding.

[0025] The second cross member 75, like the first cross member, has a second central member 76 and a second extension member 77, as shown in Figure 5. The second central member 76, like the first central member 72, extends in the vehicle width direction and is joined to the lower surface of the floor panel 17. The second extension member 77 is a member that extends outward in the vehicle width direction from the outer part of the second central member 76 in the vehicle width direction, and the outer part of the second central member 76 and the inner part of the second extension member 77 may be joined, for example, by spot welding.

[0026] The outer portion of the second extension member 77 in the vehicle width direction is joined to a hanger member 82, etc. The hanger member 82 is a member provided on the side member 20. A trailing arm (not shown) is connected to the hanger member 82. In this example, as shown in Figures 6 and 8, the hanger member 82 is a member that extends downward from the lower surface of the side member 20 to the vehicle, and is a highly rigid member made of metal. A load is applied to the hanger member 82 via the trailing arm. Therefore, the hanger member 82 has the rigidity to withstand the load.

[0027] Next, the battery mount members 30, which constitute a part of the vehicle frame, will be described. In this embodiment, two battery mount members 30 are arranged along the bottom surface 23 of the side member 20, spaced apart from each other in the vehicle's longitudinal direction. Each battery mount member 30 is made of a metal material and has high rigidity. Each battery mount member 30 is a member that extends in the vehicle's longitudinal direction and is joined to the lower part of the side member 20. As shown in Figures 6 to 8, the battery mount member 30 has an inner wall portion 31, an outer wall portion 32, and a bottom surface portion 33, and, like the side member 20, has a U-shaped cross-section.

[0028] The upper part of the inner wall portion 31 of the battery mount member 30 is joined to the inner wall portion 21 of the side member 20 by spot welding. Similarly, the upper part of the outer wall portion 32 of the battery mount member 30 is joined to the outer wall portion 22 of the side member 20 by spot welding. As a result, the battery mount member 30 and the bottom portion 23 of the side member 20 form a closed cross-sectional structure in cross-section. This improves rigidity and allows the battery pack 10 to be stably suspended. Furthermore, the side member 20 and the battery mount member 30 make it possible to construct a vehicle frame with high rigidity.

[0029] As shown in Figure 5, the intermediate portion of the inner wall 31 of the battery mount member 30 in the vehicle's longitudinal direction is provided with a flange 31a that is joined to the first cross member 26. The flange 31a is joined to the lower surface of the first cross member 26 by spot welding. By joining the first cross member to the battery mount member 30 and, as described above, to the side member 20, it is possible to construct a vehicle body frame with high rigidity.

[0030] As shown in Figures 4 and 8, closing portions 34 are provided at the front and rear ends of the battery mount member 30. The closing portion 34 is plate-shaped and is joined to the inner wall portion 31, the outer wall portion 32, and the bottom surface portion 33 of the battery mount member 30. Furthermore, a flange is provided at the upper end of the closing portion 34, and this flange is joined to the bottom surface portion 23 of the side member 20. As a result, a closed space is formed inside the battery mount member 30, and a closed cross-sectional structure is formed in the planar cross-section of the battery mount member 30, making it possible to ensure high rigidity of the battery mount member 30.

[0031] Here, we will describe the configuration in which the battery pack 10 is suspended from the vehicle body. The battery pack 10 is suspended from the vehicle body, such as the side member 20, via the battery mount member 30 and the battery suspension bracket 35.

[0032] As shown in Figures 6 to 8, the battery suspension bracket 35 is suspended from the bottom surface 33 of the battery mount member 30 via an axle member and is positioned below the bottom surface 33 of the battery mount member 30. As shown in Figures 2 to 4, the battery suspension bracket 35 has a predetermined widthwise length and extends in the longitudinal direction of the vehicle. The inner end of the battery suspension bracket 35 in the vehicle width direction is connected to the side surface of the battery pack 10, as shown in Figures 7 and 8.

[0033] Next, the side sill 40 of this embodiment will be described. The side sill 40 is located below the door opening 27 provided on the side of the vehicle, extends in the longitudinal direction of the vehicle, and, like the side member 20, constitutes the vehicle body frame. The front part of the side sill 40 may bulge inward and be joined to the inner part of the side member 20 in the vehicle width direction. As shown in Figures 6 to 8, the side sill 40 has a lower inner panel 41, an upper inner panel 45, and an upper outer panel 50. The side sill 40 also has an outer part that is located on the outermost side of the vehicle. In this embodiment, as shown in Figures 2 and 4, the outer part of the side sill 40 is made up of a part of the side body outer panel 28 that constitutes the outermost part of the vehicle. The outer part of the side sill 40 may be arranged to cover the lower inner panel 41 and the upper inner panel 45 from the outside in the vehicle width direction.

[0034] As shown in Figures 1 and 6, the upper outer panel 50 (upper plate portion) extends horizontally in the longitudinal direction of the vehicle, and the upper surface of the upper outer panel 50 functions as a footrest when occupants get in and out of the door opening 27. In this embodiment, the battery pack 10 is mounted on the lower side of the floor portion, and the floor portion is set slightly higher, so the upper outer panel 50 is effective as a footrest. Although not shown, a bead may be provided on the upper surface of the upper outer panel 50 as an anti-slip measure, for example. In this case, the bead may be formed to extend in the vehicle width direction, or it may be formed to extend at a slight inclination with respect to the vehicle width direction. A door rail 55 on which a sliding door (not shown) runs is joined to the lower surface of the upper outer panel 50.

[0035] An upper flange portion 51 projecting upward is provided on the inner side of the upper surface of the upper outer panel 50 in the vehicle width direction. The upper flange portion 51 is joined to the outer wall portion 22 of the side member 20 by spot welding. In addition, a rear flange portion 52 projecting upward is provided at the rear end of the upper surface of the upper outer panel 50. For example, as shown in Figures 6 and 8, the rear flange portion 52 is joined to the side panel 16 located on the outside of the upper floor panel 18, for example, by spot welding. In this example, the cushion portion of the rear seat (not shown) is installed on the upper floor panel 18.

[0036] As shown in Figures 6 to 8, the upper inner panel 45 is a panel that covers the door rail 55 from the inside in the vehicle width direction and from the bottom of the vehicle. The upper inner panel 45 has a bottom portion 46 (lower plate portion), an inner wall portion 47 (inner wall portion), an upper flange portion 47a, and an outer wall portion 48. The bottom portion 46 is positioned below the lower surface of the upper outer panel 50 with a gap between them. The bottom portion 46 is approximately horizontal and extends in the longitudinal direction of the vehicle. The bottom portion 46 is positioned below the door rail 55 with a gap between them and covers the door rail 55 from below.

[0037] The inner wall portion 47 extends upward from the inside in the vehicle width direction of the bottom surface portion 46 to the lower surface of the upper outer panel 50. The inner wall portion 47 is positioned at a distance from the inside in the vehicle width direction of the door rail 55, and is positioned to cover the door rail 55 from the inside in the vehicle width direction. The upper flange portion 47a is the portion that protrudes outward in the vehicle width direction from the upper end of the inner wall portion 47 and is joined to the lower surface of the upper outer panel 50 by spot welding. For example, the lower arm provided at the bottom of the sliding door is positioned in the space formed by the upper outer panel 50, the inner wall portion 47 of the upper inner panel 45, and the bottom surface portion 46, and travels on the door rail 55.

[0038] The outer wall portion 48 of the upper inner panel 45 is a wall portion that extends downward from the outer end in the vehicle width direction of the bottom surface portion 46. As shown in Figure 6, a stepped portion 48a is provided in the middle of the outer wall portion 48 in the vehicle vertical direction. The lower side of the stepped portion 48a is positioned further outward in the vehicle width direction compared to the upper side of the stepped portion 48a. By providing the stepped portion 48a, it is possible to improve the rigidity in the vehicle longitudinal direction. The outer wall portion 48 located below the stepped portion 48a is joined to the lower inner panel 41, for example, by spot welding.

[0039] Next, the lower inner panel 41 will be described. As shown in Figures 6 to 8, the lower inner panel 41 is a panel positioned below the upper inner panel 45. The lower inner panel 41 has an outer wall portion 42, an inclined surface portion 43, and an inner wall portion 44. The outer wall portion 42 is a side wall facing outward in the vehicle width direction and extends in the vehicle's longitudinal direction. The upper part of the outer wall portion 42 of the lower inner panel 41 is joined to the lower part of the outer wall portion 48 of the upper inner panel 45 by spot welding on the inside.

[0040] As shown in Figures 6 to 8, the inclined surface portion 43 of the lower inner panel 41 is the part that extends downward from the lower end of the outer wall portion 42 in the vehicle width direction, sloping downward from the vehicle. The inner wall portion 44 is a side wall that extends downward from the inner end of the inclined wall portion in the vehicle width direction. In the vehicle width direction, the inner wall portion 44 of the lower inner panel 41 is located below the door rail 55.

[0041] Next, the reinforcement 60 will be described. As described above, the reinforcement 60 is a member configured to connect the lower part of the side sill with the vehicle body frame, and is made of a metal material. The reinforcement 60 in this embodiment has a flat portion 61 extending in the vehicle width direction, and a vertical wall portion 62 that protrudes upward from the inner end of the flat portion 61 in the vehicle width direction and extends along the vehicle's longitudinal direction. In addition, a protruding portion 63 is provided at the front of the outer portion of the flat portion 61 in the vehicle width direction, protruding outward in the vehicle width direction.

[0042] The upper surface of the planar portion 61 of the reinforcement 60 on the outer side in the vehicle width direction is joined to the lower surface 46 of the bottom surface portion 46 of the upper inner panel 45 of the side sill 40 by spot welding. In addition, the vertical wall portion 62 of the reinforcement 60 is joined to the outer wall portion 32 of the battery mount member 30, which constitutes part of the vehicle body frame, by spot welding. In this embodiment, the rigidity of the reinforcement 60 in the vehicle width direction is set lower than the rigidity of the vehicle body frame (battery mount member 30 and side member 20) in the vehicle width direction.

[0043] In the side structure of this embodiment, the battery pack 10 is positioned on the inside of the vehicle body frame. For example, when subjected to an impact load such as a side collision, it is necessary to suppress the intrusion of the impacting object into the battery pack 10. In this embodiment, the battery mount member 30 and side member 30, which constitute the high-rigidity vehicle body frame, are positioned on the outside in the vehicle width direction of the battery pack 10. Therefore, the impact load can be received by a highly rigid member.

[0044] For example, impact loads resulting from side collisions are first applied to the side sill 40. If the impact load applied to the side sill 40 causes it to deform, for example, inward in the vehicle width direction, then that load is applied to the reinforcement 60. In addition, a portion of the impact energy from the impact load is converted into deformation energy as the side sill 40 deforms.

[0045] When an impact load is applied to the reinforcement 60, the reinforcement 60 deforms in a way that it collapses in the vehicle width direction while resisting the impact load. The impact energy applied to the reinforcement 60 is converted into deformation energy as the reinforcement 60 deforms and collapses. As a result, a portion of the impact load is absorbed by the reinforcement 60.

[0046] The side sill 40 and reinforcement 60 absorb the impact load, thereby reducing the impact energy of the impact load input to the battery mount member 30. Here, since the battery mount member 30 has higher rigidity than the reinforcement 60, it is able to withstand the impact load with reduced impact energy.

[0047] Furthermore, as shown in Figures 6 to 8, the battery mount member 30 is joined to the side member 20, so that the side member 20 and the battery mount member 30 can withstand impact loads. Since the side member 20 is longer in the vehicle's longitudinal direction than the battery mount member 30, the load applied to the battery mount member 30 is transmitted to the side member 20, and can be effectively transmitted to the front and rear of the vehicle, thereby effectively distributing the load. Therefore, according to the above configuration of this embodiment, it is possible to reduce the impact load transmitted to the rear of the battery pack 10, and the battery pack 10 can be protected from impact loads.

[0048] Furthermore, according to this embodiment, by providing the reinforcement 60, impact loads can be effectively absorbed between the side sill 40 and the side member 20, so the side member 20 can be positioned outward in the vehicle width direction, and as a result, a larger battery pack 10 can be placed in the limited space below the floor.

[0049] In this embodiment, as shown in Figures 6 to 8, a gap S is formed between the battery mount member 30 and the side sill 40 in the vehicle width direction, and the reinforcement 60 is positioned to cover the gap S from below. More specifically, a gap S is formed between the inner wall portion 46 of the upper inner panel 41 of the side sill 40 and the outer wall portion 32 of the battery mount member 30. The flat portion 61 of the reinforcement 60 is positioned to cover the gap S from below.

[0050] For example, the gap S functions as a stroke for shock absorption when subjected to an impact load such as a side collision. For example, when the side sill 40 deforms toward the inside of the vehicle due to an impact load such as a side collision, the members constituting the side sill 40 penetrate into the area of ​​the gap S. If the reinforcement 60 is not provided, there will be fewer members to deform to absorb the shock in the area of ​​the gap S, which may result in a low shock absorption effect. In contrast, in this embodiment, when an impact load is applied, the planar portion 61 of the reinforcement 60 deforms so as to collapse, thereby deforming the reinforcement 60 due to the impact energy and absorbing the impact energy.

[0051] Furthermore, by providing the reinforcement 60, it becomes easier to control the direction of the crushing deformation of the side sill 40, making it possible to absorb the impact load in the desired direction within the gap S region.

[0052] Furthermore, in this embodiment, the side sill 40 has, as described above, an upper outer panel 50 (upper plate portion) extending in the vehicle's longitudinal direction, a bottom surface portion 46 (lower plate portion) of an upper inner panel 41 positioned below the upper outer panel 50 at a distance, and an inner wall portion 47 extending upward from the inner end of the bottom surface portion 46 in the vehicle width direction and joined to the lower surface of the upper outer panel 50. Also, as shown in Figures 4 and 6 to 8, an opening 49 is provided on the outer side of the side sill 40 in the vehicle width direction, opening in the vehicle width direction and extending in the vehicle's longitudinal direction, with the upper outer panel 50 positioned above the opening 49 and the bottom surface portion 46 of the upper inner panel 41 positioned below the opening 49. A door rail 55 is attached to the lower surface of the upper outer panel 50 located on the outer side of the inner wall portion 46 in the vehicle width direction, and the reinforcement 60 is positioned on the inner side of the opening 49 in the vehicle width direction, along the longitudinal direction of the opening 49.

[0053] As described above, the side sill 40 of this embodiment is provided with an opening 49, which reduces its rigidity. However, since the door rail 55 is positioned along the longitudinal direction of the opening 49, rigidity can be ensured near the opening 49. Furthermore, since the reinforcement 60 is positioned along the longitudinal direction (vehicle front-rear direction) of the door rail 55 and the opening 49, impact loads can be effectively absorbed by the reinforcement 60 in the easily deformable parts of the side sill 40.

[0054] Furthermore, in this embodiment, as shown in Figure 5, in a plan view, a portion of the door rail 55 and a portion of the reinforcement 60 are arranged to overlap. In this example, the front portion of the planar portion 61 and the protruding portion 63 of the reinforcement 60 are positioned below the door rail 55.

[0055] The door rail 55 is a component for the sliding door to travel on and has high rigidity. Since the door rail 55 is joined to the lower surface of the upper outer panel 50, which is part of the side sill 40, the surface rigidity of the upper outer panel 50 is improved.

[0056] Furthermore, the front portion of the door rail 55 curves inward in the vehicle width direction as it approaches the front of the vehicle. On the other hand, the front portion of the flat portion 61 of the reinforcement 60 is provided with a protrusion 63, so the length in the vehicle width direction is longer at the front of the flat portion 61 than at the rear. As described above, since the front portion of the door rail 55 curves inward, the area in which the door rail 55 is positioned is wider at the front than at the rear. In this embodiment, the front portion of the flat portion 61 where the protrusion 63 is provided overlaps with the door rail 55 in a plan view.

[0057] The impact load from a side collision is transmitted inward in the vehicle width direction via the door rail 55. In this case, in the region where the reinforcement 60 and the door rail 55 overlap in a plan view, the load is more easily transmitted to the reinforcement 60. This makes it easier for the reinforcement 60 to absorb the load. In this embodiment, the planar portion 61 of the reinforcement 60 is provided with a bead that extends in the vehicle width direction. This sets the reinforcement 60 to the intended rigidity.

[0058] Furthermore, in this embodiment, the inner portion of the reinforcement 60 in the vehicle width direction is joined to the battery mount member 30, and the inner portion of the first cross member 71 in the vehicle width direction is joined to the inner portion of the battery mount member 30 in the vehicle width direction. Specifically, the vertical wall portion 62 of the reinforcement 60 is joined to the outer wall portion 32 of the battery mount member 30, and the flange portion 31a of the inner wall portion 31 of the battery mount member 30 is joined to the first extension member 73 of the first cross member 71.

[0059] As a result, the first cross member 71 supports the side member 20 and the battery mount member 30, and the load applied from the reinforcement 60 to the side member 20 and the battery mount member 30 can be transmitted to the first cross member 71. Consequently, the load is effectively distributed, and the load applied to the battery pack 10 is suppressed.

[0060] Furthermore, in this embodiment, as described above, the inner portion of the first cross member 71 in the vehicle width direction is joined to the side member 20 and the battery mount member 30, so that deformation of the side member 20 and the battery mount member 30 toward the vehicle can be suppressed. As a result, the load acting on the battery pack 10 is suppressed.

[0061] In this embodiment, side brackets 81 are positioned behind the reinforcement 60 at a distance from each other. The side brackets 81 are plate-shaped members that are joined to the inner wall portion 47 of the upper inner panel 45 of the side sill 40, the inner wall portion 44 of the lower inner panel 41, and the outer wall portion 84 of the hanger member 82.

[0062] Since the side bracket 81 has lower rigidity than the vehicle frame and hanger member 82, it can deform to absorb impact loads from side collisions. Furthermore, because the side bracket 81 is joined to the hanger member 82, its rigidity can be set to be high in the vertical direction of the vehicle. Therefore, the side bracket 81 can be used as a contact point for jacking up the vehicle.

[0063] The description of this embodiment is illustrative for explaining the present invention and does not limit the invention as described in the claims. Furthermore, the configuration of each part of the present invention is not limited to the above embodiment, and various modifications are possible within the technical scope described in the claims.

[0064] For example, in this embodiment, the reinforcement 60 has a plate-shaped planar portion 61 that extends continuously in the vehicle direction, but it is not limited to this. For example, a plurality of plates, each shorter in length in the vehicle longitudinal direction than the planar portion 61 of this embodiment, may be arranged at intervals from each other in the vehicle longitudinal direction.

[0065] In this embodiment, the upper outer panel 50 constituting the side sill 40 functions as a footrest when an occupant gets in and out of the door opening 27, as described above. Therefore, for example, the structure of the side sill 40 in this embodiment is effective for vehicles with a high floor. For example, in vehicles having a so-called cab-over structure in which the front seats (driver's seat and passenger seat) are located above the electric motor, the structure of the side sill 40 in this embodiment is effective as a countermeasure against side collisions. Furthermore, even in vehicles where the electric motor is located below the front seats, for example, a space R (Figure 1) is provided below the front seats and above the front of the battery pack 10, and any device can be placed there, the structure of the side sill 40 in this embodiment is effective as a countermeasure against side collisions. [Explanation of Symbols]

[0066] 10 Battery Packs 11 Top part 12 Side wall section 13 Bottom part 14 Front wall 15 Rear wall 16 Side Panels 17 Floor Panel 18 Upper floor panel 20 Side Members 20a Reinforcement plate 20b Reinforcement Plate 21 Inner wall section 21a Inner flange portion 22 Exterior wall 22a Outer flange portion 23 Bottom part 25 Upper reinforcement plate 25a Flat part 25b Flange section 26 Lower reinforcement plate 26a Flat part 26b Flange section 27 Door opening 28 Side Body Outer Panel 30 Battery Mount Members 31 Inner wall section 31a Flange 32 Exterior wall 33 Bottom part 34 Closing part 35 Battery suspension bracket 40 Side Sill 41 Lower Inner Panel 42 Exterior wall 43 Slope section 44 Inner wall section 45 Upper Inner Panel 46 Bottom part (lower plate part) 47. Interior wall section (interior wall section) 47a Upper flange portion 48 Exterior wall 48a Stepped section 49 Opening 50 Upper outer panel (top plate section) 51 Upper flange section 52 Rear flange section 55 Door rails 60 Reinforcement 61 Plane part 62 Vertical wall section 63 Protrusion 71. First Crossmember 72 First Central Member 72f Front flange section 72r Rear flange section 73 First Extension Member 73a Bottom part 73b Vertical flange section 73f Front flange section 73r Rear flange section 75. Second Crossmember 76 Second Central Member 77 Second Extension Member 81 Side Bracket 82 Hanger components 84 Exterior wall S gap R space part

Claims

1. The battery pack is located on the lower side of the vehicle's floor, Below the floor portion, the vehicle body frame is positioned on the outside of the battery pack in the vehicle width direction and extends in the vehicle's longitudinal direction, The side sills are positioned at intervals on the outer side of the vehicle body frame in the width direction and extend in the front-rear direction of the vehicle, A side structure of an electric vehicle having, The lower part of the side sill has a reinforcement that connects it to the vehicle body frame, A side structure for an electric vehicle, characterized in that the rigidity of the reinforcement in the vehicle width direction is set lower than the rigidity of the vehicle body frame in the vehicle width direction.

2. The vehicle frame includes a side member extending in the longitudinal direction of the vehicle, and a battery mount member joined to the lower part of the side member and extending in the longitudinal direction of the vehicle. In the vehicle width direction, a gap is formed between the battery mount member and the side sill. The side structure of an electric vehicle according to claim 1, characterized in that the reinforcement is arranged to cover the gap from below.

3. The side sill comprises an upper plate portion extending in the longitudinal direction of the vehicle, a lower plate portion positioned below the upper plate portion at a distance from it, and an inner wall portion extending upward from the inner end of the lower plate portion in the vehicle width direction and joined to the lower surface of the upper plate portion. An opening is provided on the outer side of the side sill in the vehicle width direction, opening in the vehicle width direction and extending in the vehicle longitudinal direction, the upper plate portion is positioned above the opening, and the lower plate portion is positioned below the opening. A door rail for opening and closing the sliding door is attached to the lower surface of the upper plate portion located on the outer side in the vehicle width direction of the inner wall portion. The side structure of an electric vehicle according to claim 1, characterized in that the reinforcement is located on the inside of the opening in the vehicle width direction and along the longitudinal direction of the opening.

4. The side structure of an electric vehicle according to claim 3, characterized in that, in a plan view, a part of the door rail and a part of the reinforcement are arranged to overlap.

5. The inner portion of the reinforcement in the vehicle width direction is joined to the battery mount member. The side structure of an electric vehicle according to claim 2, characterized in that the inner portion in the vehicle width direction of a cross member extending in the vehicle width direction is joined to the inner portion in the vehicle width direction of the battery mount member.

6. The side structure of an electric vehicle according to claim 5, characterized in that the inner portion of the cross member in the vehicle width direction is joined to the side member and the battery mount member.

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