JP7381355B2 - Side rails and electric vehicles - Google Patents

Description

The present invention relates to a side rail disposed on the outside of a battery pack in the vehicle width direction, and an electric vehicle equipped with the side rail.

BACKGROUND ART Conventionally, from the viewpoint of reducing the burden on the environment, development of electric vehicles such as electric vehicles and hybrid vehicles that run by supplying electric power from a drive battery to a motor has been progressing. In recent years, electric vehicles have been developed in the field of commercial vehicles such as trucks (for example, see Patent Document 1).
Generally, commercial vehicles are heavier than passenger cars, so in electric commercial vehicles, it is required to increase the capacity of a battery pack made up of a plurality of batteries in order to ensure a cruising range. Battery packs tend to become larger as their capacity increases, so in vehicles equipped with a ladder frame, the battery pack is mounted between a pair of side rails due to the layout.

Japanese Patent Application Publication No. 2016-113063

As described above, the battery pack placed between the side rails is supported from below by a lifter such as a hydraulic elevating device when it is attached to or removed from the side rails during the vehicle manufacturing process or maintenance process. It is moved in the vehicle width direction through the space below the rails.
However, a battery pack whose height dimension (dimension in the vehicle height direction when mounted on a vehicle) has been increased due to the increase in size may not be able to pass through the space below the side rail while being placed on the lifter. In such a case, in order to avoid interference between the battery pack and the side rails, it is necessary to lift the entire vehicle body including the side rails, which complicates the work process and increases equipment costs.

The present invention was developed in view of the above-mentioned problems, and one of the purposes is to simplify the work process and reduce equipment costs when installing and removing battery packs.

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.
(1) The side rail according to this application example is disposed outside a battery pack in the vehicle width direction in a vehicle, and includes a first region that includes an overlapping portion that overlaps with the battery pack when viewed in the vehicle width direction; The vehicle includes a second region adjacent to the first region in the vehicle length direction, and the lower end of the first region is higher in the vehicle height direction than the lower end of the second region.

As a result, the distance between the bottom edge of the first area and the ground becomes longer than the distance between the bottom edge of the second area and the ground, so there are more battery packs below the first area than below the second area. A large space (dimension in the vehicle height direction) for moving the vehicle is secured. Therefore, when moving the battery pack through the space below the first area, interference between the lower end of the first area and the battery pack can be easily avoided.

Therefore, it is possible to move the battery pack through the space below the first area while avoiding interference between the lower end of the first area and the battery pack without lifting the side rail. Therefore, the work process for attaching and detaching the battery pack is simplified. Furthermore, since equipment for lifting the side rails is not required, equipment costs are suppressed.

(2) In the side rail according to this application example, the lower end of the end portion of the first region in the vehicle length direction may be higher in the vehicle height direction as it becomes farther apart from the lower end of the adjacent second region.
If the lower end of the end in the vehicle length direction of the first region is configured in this way, the cross section of the side rail (in the vehicle width direction and the vehicle height direction Sudden changes in the cross section along the line are suppressed. This suppresses sudden changes in the strength and rigidity of the side rails in the vehicle length direction, thereby alleviating stress concentration. Therefore, deformation of the side rail is suppressed.

(3) In the side rail according to this application example, the lower end of the intermediate portion between the end portions of the first region may have a constant height in the vehicle height direction.
If the lower end of the intermediate portion of the first region in the vehicle length direction is configured in this way, a large space for moving the battery pack is secured below the intermediate portion, so that the lower end of the first region and the battery pack are interference can be more easily avoided. Therefore, the workability of attaching and detaching the battery pack is improved.

(4) In the side rail according to this application example, the dimension of the first region in the vehicle height direction may be smaller than the dimension of the second region in the vehicle height direction.
If the dimension in the vehicle height direction is smaller in the first area than in the second area, space for moving the battery pack is secured below the first area, while strength and rigidity are ensured in the second area. be done.

(5) In the side rail according to this application example, the upper end of the first region may have a constant height in the vehicle height direction.
If the upper end of the first region is configured in this way, the first region has a simple shape, and it becomes easy to arrange other devices on the first region.

(6) In the side rail according to this application example, an upper end of an end in the vehicle length direction of the first region may be flush with an upper end of the adjacent second region.
If the upper end of the end of the first region in the vehicle length direction is configured in this way, the connecting portion between the first region and the second region adjacent thereto will have a simple shape, so that the first region and the second region can be easily connected. It becomes easy to arrange other devices on the connecting portion between the two areas.

(7) In the side rail according to this application example, the first region and the second region may have equal dimensions in the vehicle height direction.
If the dimensions in the vehicle height direction are equal in the first region and the second region, sudden changes in the cross section of the side rail are suppressed at the connection portion between the first region and the second region. This suppresses sudden changes in the strength and rigidity of the side rails in the vehicle length direction, thereby alleviating stress concentration. Therefore, deformation of the side rail is suppressed. Further, by ensuring the same strength and rigidity as the second region in the first region, deformation of the first region is suppressed.

(8) The electric vehicle according to this application example is characterized by including the side rail described in any one of (1) to (7) above.
In such an electric vehicle, by providing the above-mentioned side rails, the work process for attaching and detaching the battery pack is simplified and equipment costs are suppressed.

(9) The electric vehicle according to this application example may include a plurality of cross members that are disposed between the pair of side rails, connect the side rails, and configure a ladder frame together with the side rails.
Even in an electric vehicle equipped with such a ladder frame, by providing the above-mentioned side rails, the work process for attaching and detaching the battery pack is simplified and equipment costs are suppressed.

According to the present invention, in attaching and detaching the battery pack, the work process can be simplified and equipment costs can be suppressed.

FIG. 1 is a top view schematically showing the overall configuration of an electric vehicle equipped with side rails according to a first embodiment. FIG. 2 is a schematic cross-sectional view (cross-sectional view taken along the line II-II in FIG. 1) of the battery pack mounted on the electric vehicle of FIG. 1 and its surroundings as seen from the front. FIG. 2 is a view (side view) of main parts of the electric vehicle of FIG. 1 viewed from the outside in the vehicle width direction. (a) and (b) are both schematic diagrams illustrating a procedure for attaching and removing a battery pack in the electric vehicle of FIG. 1. FIG. FIG. 4 is a view (corresponding to FIG. 3) of main parts of an electric vehicle including side rails according to a second embodiment, viewed from the outside in the vehicle width direction. FIG. 3 is a schematic cross-sectional view (corresponding to FIG. 2) of a battery pack and its surroundings according to a modification seen from the front.

A side rail and an electric vehicle as embodiments will be described with reference to the drawings. The following embodiment is merely an example, and there is no intention to exclude the application of various modifications and techniques not explicitly described in this embodiment. Each configuration of the embodiments described below can be modified in various ways without departing from the spirit thereof. Moreover, they can be selected or combined as necessary.

[1. First embodiment]
[1-1. composition]
<Vehicle>
The side rail 1 according to the first embodiment is applied to a vehicle 20 shown in FIG. Hereinafter, the forward direction of the vehicle 20 will be referred to as the front (FR), the opposite direction will be referred to as the rear, and the longitudinal direction will also be referred to as the vehicle length direction. Further, the left side (LH) and the right side are defined based on the forward facing state of the vehicle 2, and the left and right direction is also referred to as the vehicle width direction. Furthermore, a direction perpendicular to both the vehicle length direction and the vehicle width direction is also referred to as the vehicle height direction, and the upper (UP) and lower directions are defined along the vehicle height direction.

The vehicle 20 of this embodiment is an electric vehicle that includes a driving battery pack 30 and a pair of side rails 1 disposed outside the battery pack 30 in the vehicle width direction. Here, a vehicle 20 that is a truck (an electric truck) is illustrated.
The vehicle 20 includes a plurality of cross members 2 that constitute a ladder frame 40 together with the side rails 1, and a drive device 50 that drives the vehicle 20 using electric power from a battery pack 30. In addition, in FIG. 1, a cab 21 in which a driver's seat is provided and a cargo box 22 arranged at the rear of the cab 21 are shown by two-dot chain lines.

Each side rail 1 extends in the vehicle length direction, and each cross member 2 extends in the vehicle width direction. The pair of side rails 1 are spaced apart from each other in the vehicle width direction. On the other hand, each cross member 2 is arranged between a pair of side rails 1 to be spaced apart from each other in the vehicle length direction, and connects the side rails 1 to each other. The ladder frame 40 composed of the side rails 1 and the cross members 2 is a ladder-shaped structure that supports heavy objects such as the battery pack 30, the drive device 50, the cab 21, and the cargo box 22.

The drive device 50 includes a motor unit 51 that operates using electric power from the battery pack 30, and a gear unit 52 to which rotational force is transmitted from the motor unit 51. Here, a driving device 50 disposed between a pair of side rails 1 is illustrated.
The gear unit 52 includes a well-known speed reduction mechanism and a differential mechanism, and reduces the rotational force transmitted from the motor unit 51 as necessary, and then transmits the rotational force transmitted from the motor unit 51 to the left and right rear wheels (drive wheels) via the rear axle 23. 24. The vehicle 20 travels by transmitting rotational force from the drive device 50 to the rear wheels 24 in this manner.

The battery pack 30 is a relatively large and large-capacity secondary battery, and is arranged between the pair of side rails 1 in front of the drive device 50. As shown in FIG. 2, the battery pack 30 is housed in a first battery housing part 31 and a second battery housing part 32 that are arranged in the vehicle height direction, and in a first battery housing part 31 and a second battery housing part 32, respectively. It has a plurality of batteries 33.

The first battery accommodating portion 31 of this embodiment has a shape like a rectangular parallelepiped with one corner cut off (see FIG. 3). More specifically, the first battery accommodating portion 31 has a recess 31c in which the upper part of the front surface 31b facing forward when mounted on the vehicle 20 is recessed into a rectangular parallelepiped shape. The first battery accommodating portion 31 is arranged in the first space S1 between the pair of side rails 1.
On the other hand, the second battery accommodating portion 32 of this embodiment has a rectangular parallelepiped shape. The second battery accommodating part 32 is arranged in the second space S2 below the first space S1, and is continuous with the first battery accommodating part 31.

Here, the first space S1 is a space hidden by the side rail 1 when the vehicle 20 is viewed from the side (viewed in the vehicle width direction). Further, the second space S2 is a space below the side rail 1 and is a space that is not hidden by the side rail 1 when the vehicle 20 is viewed from the side.
The first battery accommodating portion 31 of the present embodiment is at least partially disposed in the first space S1, and at least partially overlaps with the side rail 1 when viewed from the side of the vehicle 20. Further, the second battery accommodating portion 32 of the present embodiment is entirely disposed in the second space S2, and does not overlap with each side rail 1 when viewed from the side of the vehicle 20.

The first battery housing section 31 is placed on the second battery housing section 32 . The first battery housing section 31 and the second battery housing section 32 are fixed to each other.
In this embodiment, the dimension W2 of the second battery accommodating portion 32 in the vehicle width direction is set larger than the dimension W1 of the first battery accommodating portion 31 in the vehicle width direction. Here, the dimension W1 in the vehicle width direction of the first battery accommodating portion 31 is smaller than the distance X between the pair of side rails 1 (W1<X), and the dimension W2 in the vehicle width direction of the second battery accommodating portion 32 is the distance above. An example where W2 is larger than X (W2>X) is shown.

In detail, the distance X between the pair of side rails 1 is determined by the distance X between the pair of side rails 1, which is defined by the distance X between the side rails 1, which are formed by protruding inward in the vehicle width direction from the upper and lower edges of the plate-shaped webs 1a along the vehicle length direction and the vehicle height direction. This is the distance based on the tip (projecting end) of the flange 1b. Therefore, the distance X described above corresponds to the length in the vehicle width direction between the right end of the flange 1b on the left side rail 1 and the left end of the flange 1b on the right side rail 1.

The first battery accommodating part 31 and the second battery accommodating part 32 are arranged so that their center lines in the vehicle width direction (see the dashed line in FIG. 2) coincide with each other. As a result, the battery pack 30 has a T-shape (inverted T-shape) with the top and bottom reversed when viewed from the front (viewed in the vehicle length direction).
The plurality of batteries 33 are connected in series and function as an energy source for driving the vehicle 20. Note that the number and arrangement of the batteries 33 are not particularly limited, and can be changed as appropriate depending on the amount of power required to drive the vehicle 20, the dimensions and characteristics of the batteries 33, and the like.

The battery pack 30 is connected to the side rail 1 via the support device 10. The support device 10 of this embodiment includes a frame-side bracket 11 coupled to a ladder frame 40, a battery-side bracket 12 coupled to a battery pack 30, and elastically connects these frame-side brackets 11 and battery-side brackets 12. It has an elastic connecting part 13 for connecting. The support device 10 elastically supports the battery pack 30 with respect to the ladder frame 40 due to the structure in which the frame side bracket 11 and the battery side bracket 12 are connected via the elastic connection part 13 in this way. This reduces vibrations transmitted from the battery pack 30 to the battery pack 30.

In this embodiment, the support device 10 is illustrated in which three frame-side brackets 11, battery-side brackets 12, and elastic connecting portions 13 are arranged at intervals in the vehicle length direction on both left and right sides of the battery pack 30. (See Figures 1 and 3). Therefore, the battery pack 30 of this embodiment is attached to the ladder frame 40 via the battery-side brackets 11, the frame-side brackets 12, and the elastic connecting portions 13, which are provided in six sets (six sets). Note that the support device 10 of this embodiment is formed laterally symmetrically.

Each frame-side bracket 11 extends outward and downward in the vehicle width direction from the side rail 1. The upper part of each frame-side bracket 11 is disposed on the outer side of the web 1a of the side rail 1 in the vehicle width direction, and is coupled to the side rail 1 by a fixing member 14 such as a bolt. On the other hand, each battery-side bracket 12 is provided to protrude outward in the vehicle width direction from an end surface 32a on the outside in the vehicle width direction of the second battery accommodating portion 32.

Each elastic connection portion 13 is, for example, a rubber bush, and is configured to include an elastic body having a substantially cylindrical or substantially truncated conical shape. The elastic connecting portion 13 absorbs external forces input in various directions (vehicle length direction, vehicle width direction, vehicle height direction, and a composite direction combining these directions). The elastic connecting portion 13 is fixed to each of the lower part of the frame-side bracket 11 and the outer end in the vehicle width direction of the battery-side bracket 12. Thereby, the elastic connecting portion 13 elastically connects the frame side bracket 11 and the battery side bracket 12.
Note that the method of fixing the elastic connecting portion 13 is not particularly limited, and for example, a fixing device such as a bolt may be used, or a method of fitting the unevenness provided on each part of the elastic connecting portion 13 may be adopted. It's okay.

<Side rail>
The side rail 1 will be explained in detail below.
As shown in FIG. 3, the side rail 1 includes a first region 3 including an overlapping portion 6 that overlaps with the battery pack 30 in a side view of the vehicle 20, and a second region 4 adjacent to the first region 3 in the vehicle length direction. , 5.

In the side rail 1, the first region 3 is aligned with the battery pack 30 in the vehicle width direction, and the second regions 4 and 5 are located in front or behind the battery pack 30. The first region 3 has an overlapping portion 6 that overlaps the battery pack 30 mounted on the vehicle 20 (hereinafter also referred to as "mounted state") in a side view. On the other hand, the second regions 4 and 5 do not entirely overlap with the mounted battery pack 30 in a side view.

The second regions 4 and 5 of this embodiment are provided adjacent to both sides (front and rear) of the first region 3 in the vehicle length direction. Hereinafter, one of the second regions 4 and 5, which is provided adjacent to the front of the first region 3 and located in front of the battery pack 30, is also referred to as the "front region 4", and the one located at the rear of the first region 3 The other region provided adjacent to the battery pack 30 and located further back than the battery pack 30 is also referred to as a "rear region 5." Further, the first area 3 is also referred to as an "overlapping area 3."
Note that the side rail 1 has a cross section (a cross section along the vehicle width direction and vehicle height direction) in the overlapping region 3, the front region 4, and the rear region 5 that has a channel shape due to the web 1a and the flange 1b. to do.

Comparing the dimensions in the vehicle height direction (hereinafter also referred to as "height dimensions"), the height dimension L1 of the overlapping region 3 of this embodiment is higher than either of the height dimensions L2 and L3 of the front region 4 and the rear region 5. (L1<L2 and L1<L3). However, the height dimension L1 of the overlapping region 3 is not constant (uniform), and is larger at the end portions 3a and 3b than at the intermediate portion 3c in the vehicle height direction. On the other hand, the height L2 of the front region 4 is constant, and the height L3 of the rear region 5 is also constant. Note that "constant" here does not necessarily have to be strictly determined to one value, and any errors that may occur in design or manufacturing are allowed.

Here, the heights (hereinafter also referred to as "height positions") of the lower end 7L of the overlapping region 3, the lower end 8L of the front region 4, and the lower end 9L of the rear region 5 in the vehicle height direction will be described in detail. Since the side rail 1 of this embodiment has a channel shape as described above, the lower ends 7L, 8L, and 9L here correspond to the lower surface (downward facing surface) of the lower flange 1b at the corresponding portion. do. Specifically, the lower end 7L of the overlapping region 3 (hereinafter also referred to as "overlapping lower end 7L") corresponds to the lower surface of the lower flange 1b in the overlapping region 3. Similarly, the lower end 8L of the front region 4 (hereinafter also referred to as "front lower end 8L") corresponds to the lower surface of the lower flange 1b in the front region 4, and the lower end 9L of the rear region 5 (hereinafter also referred to as "rear lower end 9L") corresponds to the lower surface of the lower flange 1b in the front region 4. ) corresponds to the lower surface of the lower flange 1b in the rear region 5.

The overlapping lower end 7L is higher (located above) than both the front lower end 8L and the rear lower end 9L in the vehicle height direction. Therefore, the distance D1 between the overlapping lower end 7L and the ground G is longer than both the distance D2 between the front lower end 8L and the ground G and the distance D3 between the rear lower end 9L and the ground G. In this way, a larger space for moving the battery pack 30 is secured below the overlapping region 3 than below the front region 4 and the rear region 5.

In the overlapping lower end 7L of this embodiment, the height positions of the end portions 3a and 3b in the vehicle length direction in the overlapping region 3 and the intermediate portion 3c are different. Hereinafter, among the ends 3a and 3b of the overlapping region 3 in the vehicle length direction, the front end 3a is also referred to as the "overlapping front end 3a", and the rear end 3b is also referred to as the "overlapping rear end 3b". Further, among the overlapping lower ends 7L, the lower end of the overlapping front end portion 3a is marked with a code “7a”, the lower end of the overlapping rear end portion 3b is marked with a code “7b”, and the lower end of the intermediate portion 3c is marked with a code “7c”. attach Note that the intermediate portion 3c is a portion between the overlapping front end portion 3a and the overlapping rear end portion 3b.

The lower end 7a of the overlapping front end portion 3a is continuous from the lower front end 8L and slopes upward toward the rear. In this way, the lower end 7a of the overlapping front end portion 3a becomes higher in the vehicle height direction as it becomes farther away from the lower end 8L of the front region 4 adjacent to the overlapping front end portion 3a. Further, the lower end 7b of the overlapping rear end portion 3b is continuous from the rear lower end 9L, and slopes upward toward the front. In this way, the lower end 7b of the overlapping rear end portion 3b becomes higher in the vehicle height direction as it becomes farther away from the lower end 9L of the rear region 5 adjacent to the overlapping rear end portion 3b. The lower ends 7a and 7b of the overlapping front end 3a and the overlapping rear end 3b have a function of suppressing sudden changes in the cross section in the overlapping region 3.

On the other hand, the lower end 7c of the intermediate portion 3c is continuous from the lower ends 7a and 7b of the overlapping front end portion 3a and the overlapping rear end portion 3b, and has a constant height position. Therefore, in the overlapping region 3, the lower end 7c of the intermediate portion 3c extends in a straight line along the vehicle length direction above the respective lower ends 7a, 7b of the overlapping front end 3a and overlapping rear end 3b.
Note that the front lower end 8L and the rear lower end 9L each have a constant height position, and extend in a straight line along the vehicle length direction below the overlapping lower end 7L.

Next, the height positions of the upper end 7U of the overlapping region 3, the upper end 8U of the front region 4, and the upper end 9U of the rear region 5 will be described in detail. Since the side rail 1 of this embodiment has a channel shape as described above, the upper ends 7U, 8U, and 9U here correspond to the upper surface (the surface facing upward) of the upper flange 1b at the corresponding portion. . Specifically, the upper end 7U of the overlapping region 3 (hereinafter also referred to as "overlapping upper end 7U") corresponds to the upper surface of the upper flange 1b in the overlapping region 3. Similarly, the upper end 8U of the front region 4 (hereinafter also referred to as "front upper end 8U") corresponds to the upper surface of the upper flange 1b in the front region 4, and the upper end 9U of the rear region 5 (hereinafter referred to as "rear upper end 9U"). ) corresponds to the upper surface of the upper flange 1b in the rear region 5.

In this embodiment, the height positions of the overlapping upper end 7U, the front upper end 8U, and the rear upper end 9U are all constant. Therefore, the overlapping upper end 7U, front upper end 8U, and rear upper end 9U extend in a straight line along the vehicle length direction above the overlapping lower end 7L, front lower end 8L, and rear lower end 9L.
Here, among the overlapping upper ends 7U, the upper end of the overlapping front end 3a is marked with a code "7d", the upper end of the overlapping rear end 3b is marked with a code "7e", and the upper end of the intermediate part 3c is marked with a code "7f". Attach. The upper end 7d of the overlapping front end portion 3a is flush with the upper end 8U of the front region 4 adjacent to the overlapping front end portion 3a. Similarly, the upper end 7e of the overlapping rear end portion 3b is flush with the upper end 9U of the rear region 5 adjacent to the overlapping rear end portion 3b.

In addition, the height position of the upper surface (upper surface of the 1st battery accommodating part 31) 31a of the battery pack 30 of the mounted state is provided higher than 7 L of duplication lower ends. In this embodiment, a battery pack 30 is illustrated in which the height position of the upper surface 31a is set higher than the overlap lower end 7L and lower than the overlap upper end 7U. However, the height position of the top surface 31a of the battery pack 30 in the mounted state only needs to be higher than the overlap lower end 7L, and for example, the height position of the upper surface 31a may be set to be higher than the height position of the overlap upper end 7U.

<Installing and removing the battery pack>
Hereinafter, with reference to FIG. 4, the procedure for attaching and detaching the battery pack 30 will be described. Such attachment and detachment of the battery pack 30 is performed, for example, during a vehicle manufacturing process or maintenance process. Here, an example is shown in which a lifter 60 such as a hydraulic lifting device is used.

First, the procedure for removing the battery pack 30 will be explained.
As shown in FIG. 4A, a lifter 60 is disposed below the battery pack 30, and its support surface 61 is raised to support the battery pack 30 from below. Next, the fixture 14 is removed, and the battery pack 30 and support device 10 are separated from the side rail 1 as one unit. Thereby, the battery pack 30 becomes movable relative to the side rail 1 together with the support device 10.

Thereafter, the support surface 61 of the lifter 60 is lowered, and the battery pack 30 and the support device 10 are lowered together. Then, as shown in FIG. 4B, when the upper surface 31a of the battery pack 30 is lowered below the overlap lower end 7L, the lifter 60 on which the battery pack 30 is placed is moved in the vehicle width direction, and the overlap area 3 is The battery pack 30 and the support device 10 are taken out to the outside of the side rail 1 in the vehicle width direction through the lower space.

Here, since the overlapping lower end 7L is located above both the front lower end 8L and the rear lower end 9L, there is a space below the overlapping area 3 that is larger in the vehicle height direction than below the front area 4 and the rear area 5. Space is secured. Therefore, when taking out the battery pack 30 through the space below the overlap area 3, even if the top surface 31a of the battery pack 30 is located at a higher position than the front lower end 8L and the rear lower end 9L, it must be lower than the overlap lower end 7L. If there is, the battery pack 30 can be taken out. In this way, in the side rail 1, since the overlapping lower end 7L is higher in the vehicle height direction than the front lower end 8L and the rear lower end 9L, there is a case where the overlapping lower end 7L is at the same height position as the front lower end 8L or the rear lower end 9L. In comparison, interference between the overlapping lower end 7L and the battery pack 30 is more easily avoided.

Attachment of the battery pack 30 can be carried out by reversing the above-described removal procedure.
In attaching the battery pack 30, the battery pack 30 on the lifter 60 and the support device 10 are moved from the outside of the overlap area 3 in the vehicle width direction to the inside of the overlap area 3 through the space below the overlap area 3. At this time, in the side rail 1, since the overlapping lower end 7L is higher in the vehicle height direction than the front lower end 8L and the rear lower end 9L as described above, interference between the overlapping lower end 7L and the battery pack 30 is easily avoided.

Then, as shown in FIG. 4B, when the battery pack 30 and the support device 10 are arranged below between the pair of side rails 1, the support surface 61 of the lifter 60 is raised, and the frame side bracket 11 is Position against. Then, as shown in FIG. 4(a), each frame-side bracket 11 is coupled to the side rail 1 using a fixture 14. Finally, the lifter 60 is lowered again and moved to the outside of the vehicle 20.

[1-2. Action and effect]
(1) According to the side rail 1 described above, the lower end 7L of the overlapping region 3 including the overlapping portion 6 that overlaps with the battery pack 30 when viewed in the vehicle width direction is connected to the front region 4 adjacent to the overlapping lower end 7L in the vehicle length direction. It is higher in the vehicle height direction than the lower ends 8L and 9L of the rear region 5. Therefore, as shown in FIG. 3, the distance D1 between the overlapping lower end 7L and the ground G is longer than the distances D2 and D3 between the front lower end 8L and the rear lower end 9L and the ground G, respectively.

Therefore, a larger space (dimension in the vehicle height direction) for moving the battery pack 30 is secured below the overlapping region 3 than below the front region 4 and the rear region 5. As a result, when the battery pack 30 is moved through the space below the overlap area 3, the overlap lower end 7L and the battery pack 30 are placed at the same height position as the front lower end 8L or the rear lower end 9L. This makes it easier to avoid interference with

Therefore, the battery pack 30 can be moved through the space below the overlap area 3 while avoiding interference between the overlap lower end 7L and the battery pack 30 without lifting the side rail 1 or the ladder frame 40 including the side rail 1. becomes possible. Therefore, the work process of attaching and detaching the battery pack 30 can be simplified. Moreover, since equipment for lifting the entire side rail 1 and ladder frame 40 is not required, the equipment cost for attaching and removing the battery pack 30 can be suppressed.

Furthermore, according to the side rail 1, the interference between the overlapping lower end 7L and the battery pack 30 can be easily avoided as described above, so that the size restriction of the battery pack 30 can be relaxed. Therefore, increasing the capacity (battery capacity) of the battery pack 30 contributes to extending the cruising distance of the vehicle 20. In particular, since the battery pack 30 of this embodiment includes the first battery housing part 31 and the second battery housing part 32, the height dimension (dimension in the vehicle height direction in the installed state) is relatively large. Accordingly, interference with the battery pack 30 can be easily avoided even in such attachment and detachment of the battery pack 30.

Note that by simplifying the work steps for attaching and detaching the battery pack 30 as described above, the time required to replace the battery pack 30 can be shortened. Therefore, when the amount of charge of the battery pack 30 decreases, it becomes possible to replace the battery pack 30 with a fully charged battery pack in a short time. Therefore, it also contributes to securing the operating time of the vehicle 20.

(2) Since the lower ends 7a and 7b of the overlapping end portion 3a and the overlapping rear end portion 3b are higher in the vehicle height direction as they are further apart from the adjacent front lower end 8L and rear lower end 9L, the overlapping region 3 and the front region 4 and rear Sudden changes in the cross section of the side rail 1 can be suppressed at each connecting portion with the region 5. This suppresses sudden changes in the strength and rigidity of the side rail 1 in the vehicle length direction, so that stress concentration can be alleviated. Therefore, while securing the space below the overlapping region 3 as described above, deformation of the side rail 1 can be suppressed.

(3) Since the height position of the lower end 7c in the middle part 3c of the overlapping region 3 is constant, as described above, the lower end 7c of the middle part 3c is In this case, a large space for moving the battery pack 30 can be secured. This makes it easier to avoid interference between the overlapping lower end 7L and the battery pack 30, so that deformation of the side rail 1 can be suppressed and workability in attaching and detaching the battery pack 30 can be improved.

(4) Since the height dimension L1 of the overlapping area 3 is smaller than the height dimensions L2 and L3 of the front area 4 and the rear area 5, a space for moving the battery pack 30 is secured below the overlapping area 3. However, strength and rigidity can be ensured in the front region 4 and the rear region 5.

(5) Since the height position of the overlapping upper end 7U is constant, the overlapping region 3 can be made into a simpler shape than when the height position of the overlapping upper end 7U is not constant. This makes it easy to arrange other devices (for example, the packing box 22) on the overlapping area 3. In particular, in this embodiment, the height positions of the overlapping upper end 7U, front upper end 8U, and rear upper end 9U are constant, and these upper ends 7U, 8U, and 9U extend in a straight line along the vehicle length direction, so the side The entire rail 1 can be made into a simpler shape. This makes it easy to arrange other devices on the side rail 1 over the entire area in the vehicle length direction.

(6) Since the upper ends 7d and 7e of the overlapping front end 3a and the overlapping rear end 3b are flush with the adjacent front upper end 8U and rear upper end 9U, respectively, the overlapping region 3, the front region 4, and the rear region 5 are Each connection part can be made into a simple shape. Thereby, it becomes easy to arrange other devices on each connecting portion between the overlapping region 3 and the front region 4 and rear region 5.

(7) According to the vehicle 20 provided with the side rail 1, since the side rail 1 is configured as described above, the work process for attaching and removing the battery pack 30 can be simplified and equipment costs can be suppressed.
(8) The vehicle 20 is provided with a plurality of cross members 2 that constitute the ladder frame 40 together with the side rails 1. Even in the vehicle 20 equipped with such a ladder frame 40, the side rails 1 can simplify the work process in attaching and detaching the battery pack 30 as described above, and can suppress equipment costs.

[2. Second embodiment]
[2-1. composition]
As shown in FIG. 5, the side rail 1' of the second embodiment has a height dimension L1' of an overlapping region 3', a front region 4', and a rear region 5' compared to the side rail 1 of the first embodiment. , L2', and L3' are different. Hereinafter, elements that are the same as or correspond to those described in the first embodiment will be denoted by the same reference numerals, and redundant explanation will be omitted.

The overlapping region 3', the front region 4', and the rear region 5' of this embodiment have the same height dimensions L1', L2', and L3' (L1'=L2'=L3'). Therefore, the height dimensions L1', L2', and L3' of the overlapping region 3', the front region 4', and the rear region 5' are all constant (uniform). Note that "equal" here does not necessarily have to be exactly the same, and any errors that may occur in design or manufacturing are allowed.

In the overlapping region 3', front region 4', and rear region 5' of this embodiment, the lower ends 7L, 8L, and 9L are respectively similar to those of the first embodiment, whereas the upper ends 7U', 8U', and 9U ' is not constant in height and extends parallel to the corresponding lower ends 7L, 8L, and 9L, respectively. Therefore, the overlapping upper end 7U' of this embodiment is higher (located above) than both the front upper end 8U' and the rear upper end 9U' in the vehicle height direction.

In the overlapping region 3', the height position of the upper end 7U' is different between the front end 3a', the rear end 3b', and the intermediate part 3c'. Specifically, the upper end 7d' of the overlapping front end portion 3a' is continuous from the front upper end 8U' and slopes upward toward the rear. Further, the upper end 7e' of the overlapping rear end portion 3b' is continuous from the upper rear end 9U' and slopes upward toward the front. The upper ends 7d' and 7e' of the overlapping front end 3a' and the overlapping rear end 3b' have the function of suppressing sudden changes in the cross section in the overlapping region 3'.

On the other hand, the upper end 7f' of the intermediate portion 3c' is continuous from the upper ends 7d' and 7e' of the overlapping front end 3a' and the overlapping rear end 3b', and has a constant height position. Therefore, in the overlapping region 3' of this embodiment, the upper end 7f' of the intermediate portion 3c' is located above the upper ends 7d' and 7e' of the overlapping front end 3a' and the overlapping rear end 3b' in the vehicle length direction. extends in a straight line along.
Note that the front upper end 8U' and the rear upper end 9U' each have a constant height position, and extend in a straight line along the vehicle length direction below the overlapping upper end 7U'.

[2-2. Action and effect]
According to the above side rail 1', the height dimensions L1', L2', and L3' of the overlapping area 3', the front area 4', and the rear area 5' are equal to each other, so that the overlapping area 3' and the front area 4' are equal to each other. Sudden changes in the cross section of the side rail 1' can be further suppressed at each connecting portion between the side rail 1' and the rear region 5'. This further suppresses sudden changes in the strength and rigidity of the side rail 1' in the vehicle length direction, thereby making it possible to further alleviate stress concentration. Therefore, deformation of the side rail 1' can be further suppressed.

Furthermore, since the height L1' of the overlapping region 3' is the same as the height dimensions L2' and L3' of the front region 4' and the rear region 5', the front region 4' and the rear region Strength and rigidity equivalent to that of the region 5' can be ensured. Thereby, deformation of the overlapping region 3' can be further suppressed.
In addition, according to the side rail 1' of this embodiment and the vehicle (electric vehicle) equipped with the same, similar operations and effects can be obtained from the same configuration as in the above embodiment.

[3. Modified example]
The battery pack 30 described above is an example. The side rails 1, 1' may be arranged on the outside in the vehicle width direction of the battery pack 30' shown in FIG. 6 instead of the battery pack 30 described above. In addition, in FIG. 6, although the side rail 1 of 1st Embodiment is illustrated, the side rail 1' of 2nd Embodiment is applicable similarly. Hereinafter, elements that are the same as or correspond to those described in the first embodiment will be denoted by the same reference numerals, and redundant explanation will be omitted.

The battery pack 30' of this modification is different from the battery pack 30 shown in the first embodiment in that the shape of the first battery accommodating part 31' and the dimension W2' in the vehicle width direction of the second battery accommodating part 32' are different from each other. are different. Specifically, in the battery pack 30', the first battery accommodating part 31' has a rectangular parallelepiped shape (the above-mentioned recess 31c is omitted), and the vehicle width direction dimension W2' of the second battery accommodating part 32' is It is set to be the same as the vehicle width direction dimension W1 of the first battery accommodating portion 31'.

In this modification as well, the first battery accommodating part 31' and the second battery accommodating part 32' are arranged so that the center lines in the vehicle width direction (see the dashed line in FIG. 6) coincide with each other. As a result, the battery pack 30' has a rectangular shape when viewed from the front (viewed in the vehicle length direction).
According to the battery pack 30' of this modification, the shape is simplified compared to the battery pack 30 of each of the embodiments described above. However, the specific shape and dimensions of the battery pack disposed between the side rails 1 and 1' are not particularly limited, and for example, the height dimension may be increased by omitting the second battery accommodating parts 32 and 32'. May be reduced.

The overlapping lower ends 7L of the side rails 1, 1' need only be higher in the vehicle height direction than the front lower ends 8L and the rear lower ends 9L, and their specific height positions are not particularly limited. For example, the lower ends 7a, 7b of the overlapping front end portions 3a, 3a' and the overlapping rear end portions 3b, 3b' may have a constant height position. Alternatively, the entire overlapping lower end 7L including the lower end 7c of the intermediate portions 3c, 3c' may be inclined upwardly or downwardly toward the front or rear.

The configuration of the support device 10 described above is an example. Further, the vehicle 20 to which the side rails 1 and 1' are applied is not limited to an electric vehicle that includes only the above-mentioned motor unit 51 as a drive source, but may be a hybrid vehicle that further includes an engine. Furthermore, the side rails 1, 1' can be applied to vehicles not equipped with the ladder frame 40, and may also be applied to commercial vehicles other than trucks. Note that the configuration of the side rails 1 and 1' described above may be applied to only one of the side rails disposed on both sides of the battery packs 30 and 30' in the vehicle width direction in the vehicle 20.

1, 1' Side rail 1a Web 1b Flange 2 Cross member 3, 3' Overlapping area (first area)
3a, 3a' Overlapping front end (end)
3b, 3b' Overlapping rear end (end)
3c, 3c' Middle part 4, 4' Front region (second region)
5,5' Posterior area (second area)
6 Overlapping part 7a Lower end 7b of overlapping front end parts 3a, 3a' Lower end 7c of overlapping rear end parts 3b, 3b' Lower end 7d of intermediate parts 3c, 3c' Upper end 7d' of overlapping front end part 3a Top end 7e of overlapping front end part 3a' Upper end 7e' of the overlapping rear end part 3b Upper end 7f of the overlapping rear end part 3b' Upper end 7f' of the intermediate part 3c Upper end 7L of the intermediate part 3c' Lower end of the overlap (lower end of the first area)
7U, 7U' Overlapping upper end (upper end of first area)
8L Lower front end (lower end of second area)
8U, 8U' Front upper end (upper end of second area)
9L Lower rear end (lower end of second area)
9U, 9U' Rear upper end (upper end of second area)
10 Support device 11 Frame side bracket 12 Battery side bracket 13 Elastic connection part 14 Fixture 20 Vehicle (electric vehicle)
21 Cab 22 Loading box 23 Rear axle 24 Rear wheels 30, 30' Battery packs 31, 31' First battery accommodating part 31a Top surface 31b Front surface 31c Recessed part 32, 32' Second battery accommodating part 32a End surface 33 Battery 40 Ladder frame 50 Drive Device 51 Motor unit 52 Gear unit 60 Lifter 61 Support surface D1 Distance D2 between the overlapping lower end 7L and the ground G Distance D3 between the front lower end 8L and the ground G Distance G between the rear lower end 9L and the ground G Ground L1 Height of the overlapping area 3 Height dimension L1' Height dimension L2 of overlapping region 3' Height dimension L2' of front region 4 Height dimension L3 of front region 4' Height dimension L3' of rear region 5 Height dimension S1 of rear region 5' 1 space S2 2nd space W1 Dimension in the vehicle width direction of the first battery accommodating portions 31, 31' W2 Dimension in the vehicle width direction of the second battery accommodating portion 32 Dimension in the vehicle width direction of the second battery accommodating portion 32' X Side rail distance between 1

Claims (8)

a driving battery pack in which a first battery accommodating part is placed and fixed on a second battery accommodating part;
a pair of side rails that are arranged on the outside of the first battery accommodating portion in the vehicle width direction and spaced apart from each other in the vehicle width direction ;
a support device that connects the battery pack to the side rail;
a fixture coupling the support device to the side rail;
The battery pack is arranged such that at least a part of the first battery accommodating part is arranged in a first space between the pair of side rails, and the whole of the second battery accommodating part is arranged in a first space below the first space. 2 space, and the dimension of the second battery storage part in the vehicle width direction is set to be larger than the distance between the pair of side rails,
The side rail has a first region including an overlapping portion that overlaps with the battery pack when viewed in the vehicle width direction, and a second region adjacent to the first region in the vehicle length direction,
The support device is coupled to an outer surface of the side rail in the vehicle width direction in the first region by the fixture,
The electric vehicle is characterized in that a lower end of the first region is higher in a vehicle height direction than a lower end of the second region. The electric vehicle according to claim 1, wherein the lower end of the end portion of the first region in the vehicle length direction is higher in the vehicle height direction as the distance from the lower end of the adjacent second region increases. The electric vehicle according to claim 2, wherein the lower end of the intermediate portion between the end portions of the first region has a constant height in the vehicle height direction. The electric vehicle according to claim 1, wherein a dimension of the first region in the vehicle height direction is smaller than a dimension of the second region in the vehicle height direction. The electric vehicle according to claim 1, wherein the upper end of the first region has a constant height in the vehicle height direction. The electric vehicle according to any one of claims 1 to 5, wherein an upper end of an end of the first region in the vehicle length direction is flush with an upper end of the adjacent second region. The electric vehicle according to any one of claims 1 to 3, wherein the first region and the second region have equal dimensions in a vehicle height direction. 8. The method according to claim 1, further comprising a plurality of cross members arranged between a pair of said side rails to connect said side rails and to constitute a ladder frame together with said side rails. Electric vehicle described.

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