Vehicle undercarriage

Abstract

The vehicle understructure is designed to allow maintenance and replacement of the detector that detects voltage abnormalities in the battery modules housed inside the battery case, without removing the battery case from the vehicle. [Solution] A vehicle understructure 10 is provided, comprising a battery case 20 mounted on the lower part of a vehicle 12, the upper wall 22 of which at least a portion also serves as a floor panel, a battery module 30 housed inside the battery case 20, and a detector 34 housed inside the battery case 20 for detecting voltage abnormalities of the battery module 30, wherein an opening 26 is formed in the upper wall 22 of the battery case 20 to allow access to the detector 34, and a lid 28 is provided that can open and close the opening 26.

Description

Technical Field

[0001] The present invention relates to a vehicle underbody structure.

Background Art

[0002] An electric vehicle including a battery case composed of a case rear having an opening and a case front that removably closes the opening has been conventionally known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in order to perform maintenance or replacement of a detector that detects an abnormal voltage of a battery module housed inside a battery case, it is necessary to remove and disassemble the battery case from the vehicle (electric vehicle). However, when the battery case is mounted under the vehicle, it is not easy to remove the battery case from the vehicle.

[0005] Therefore, an object of the present invention is to obtain a vehicle underbody structure that can perform maintenance or replacement of a detector that detects an abnormal voltage of a battery module housed inside a battery case without removing the battery case from the vehicle.

Means for Solving the Problems

[0006] To achieve the above objective, the vehicle understructure according to the first embodiment of the present invention comprises a battery case mounted on the underside of a vehicle, the upper wall of which at least a portion also serves as a floor panel; a battery module housed inside the battery case; and a detector housed inside the battery case for detecting voltage abnormalities of the battery module, wherein an opening is formed in the upper wall of the battery case to provide access to the detector, and a lid portion is provided that can open and close the opening.

[0007] According to the first embodiment of the invention, a battery case is mounted on the underside of the vehicle, with at least a portion of its upper wall also serving as a floor panel. Inside the battery case are a battery module and a detector for detecting voltage abnormalities in the battery module. An opening is formed in the upper wall of the battery case to provide access to the detector, and a lid is provided that can open and close this opening. Therefore, by removing the lid, the detector can be accessed through the opening. Thus, maintenance and replacement of the detector can be performed without removing the battery case from the vehicle.

[0008] Furthermore, a second embodiment of the vehicle understructure according to the present invention is the vehicle understructure according to the first embodiment, wherein the opening is formed in the upper wall of the battery case located between the dash panel, which constitutes the front wall of the passenger compartment, and the accelerator pedal, in a side view taken from the vehicle width direction.

[0009] According to the second embodiment of the invention, in a side view taken from the vehicle width direction, the opening is formed in the upper wall of the battery case located between the dash panel and the accelerator pedal, which constitute the front wall of the passenger compartment. In other words, the opening is formed in a part that is not easily accessible to the occupants. Therefore, there is no risk of the cover being inadvertently removed from inside the passenger compartment, and safety is ensured.

[0010] Furthermore, a third embodiment of the vehicle understructure according to the present invention is the vehicle understructure according to the second embodiment, wherein the opening is formed with the vehicle width direction as the longitudinal direction, and the upper surface of the front cross member, which is installed between a pair of left and right rockers on the lower side of the dash panel, is flush with the upper surface of the upper wall of the battery case.

[0011] According to the third embodiment of the invention, the opening is formed with the vehicle width direction as the longitudinal direction, and the upper surface of the front cross member, which is installed between a pair of left and right rockers on the lower side of the dash panel, is flush with the upper surface of the upper wall of the battery case. Therefore, compared to the case in which the upper surface of the front cross member and the upper surface of the upper wall of the battery case are not flush, the suppression of the increase in vehicle weight and the reinforcement of the vicinity of the opening in the battery case are maximally achieved. In this invention, "flush" also includes "approximately flush" with a slight offset.

[0012] Furthermore, the fourth embodiment of the vehicle understructure according to the present invention is a vehicle understructure according to any one of the first to third embodiments, wherein the opening is formed with the vehicle width direction as the longitudinal direction, and a cross portion extending in the vehicle width direction is provided on the lower wall side inside the battery case and in a portion facing the opening in the vehicle vertical direction.

[0013] According to the fourth embodiment of the invention, the opening is formed with the vehicle width direction as the longitudinal direction, and a cross portion extending in the vehicle width direction is provided on the lower wall side inside the battery case, in a portion facing the opening in the vehicle vertical direction. Therefore, compared to the case where the cross portion is not provided, the reduction in strength near the opening in the battery case is effectively suppressed. [Effects of the Invention]

[0014] As described above, according to the present invention, maintenance and replacement of the detector that detects voltage abnormalities in the battery module housed inside the battery case can be performed without removing the battery case from the vehicle. [Brief explanation of the drawing]

[0015] [Figure 1] This is a schematic plan view showing the vehicle understructure according to this embodiment. [Figure 2] This is a schematic side cross-sectional view showing the vehicle understructure according to this embodiment. [Modes for carrying out the invention]

[0016] The embodiments of the present invention will be described in detail below with reference to the drawings. For the sake of explanation, in each figure, the arrow UP will indicate the upward direction of the vehicle, the arrow FR will indicate the forward direction of the vehicle, and the arrow RH will indicate the rightward direction of the vehicle. In the following description, unless otherwise specified, the directions of up, down, front, back, and left and right will refer to the up, down, front, back, and left and right directions of the vehicle. The left and right direction is synonymous with the vehicle width direction.

[0017] As shown in Figures 1 and 2, the vehicle understructure 10 according to this embodiment is applied to a vehicle 12 such as an electric vehicle having a battery case 20, and the battery case 20 is mounted on the underside of the vehicle 12. As shown in Figure 2, the battery case 20 has an upper wall 22 and a lower wall 24, with an upper peripheral wall 23 integrally attached vertically to the periphery of the upper wall 22, and a lower peripheral wall 25 integrally attached vertically to the periphery of the lower wall 24.

[0018] An upper flange portion 23A is integrally formed on the periphery of the upper peripheral wall 23, and a lower flange portion 25A is integrally formed on the periphery of the lower peripheral wall 25, which also protrudes outward. The battery case 20 is formed into a roughly rectangular box shape by overlapping and joining the upper flange portion 23A and the lower flange portion 25A vertically.

[0019] As shown in Figure 1, at least a portion of the upper wall 22 is exposed from between multiple cross members 15 installed between a pair of left and right rockers 13, and also serves as the floor panel of the vehicle 12. In addition, the vehicle 12 according to this embodiment is, as an example, a right-hand drive electric vehicle with the driver's seat on the right side.

[0020] As shown in FIG. 2, inside the battery case 20, a battery module 30 formed by stacking a plurality of battery cells 32 and a detector 34 for detecting an abnormal voltage of the battery module 30 are accommodated. The detector 34 is disposed at the front end inside the battery case 20 and on the driver's seat side (right side), and the battery module 30 is disposed on the rear side of the detector 34.

[0021] Also, at the front end of the upper wall 22 of the battery case 20 and on the driver's seat side (right side), an opening 26 accessible to the detector 34 is formed, and a lid 28 capable of opening and closing the opening 26 is provided. In plan view, the opening 26 is formed in a substantially rectangular shape with the vehicle width direction as the longitudinal direction, and the lid 28 is formed in a substantially rectangular flat plate shape with the vehicle width direction as the longitudinal direction (see FIG. 1).

[0022] As shown in FIG. 2, a short cylindrical portion 26A extending downward is integrally formed at the peripheral edge of the opening 26, and a short cylindrical portion 28A extending downward is also integrally formed at the peripheral edge of the lid 28. The outer diameter of the short cylindrical portion 28A of the lid 28 is formed slightly larger than the inner diameter of the short cylindrical portion 26A of the opening 26.

[0023] Therefore, the lid 28 can close the opening 26 by fitting (press-fitting) the short cylindrical portion 28A with a predetermined friction (sliding resistance) to the short cylindrical portion 26A of the opening 26. That is, with such a configuration, the opening 26 can be opened and closed by the lid 28.

[0024] Also, as shown in FIG. 2, the opening 26 of the battery case 20 is formed in the upper wall 22 of the battery case 20 between the lower end portion 16A on the vehicle interior side of the dash panel 16 constituting the front wall of the vehicle interior and the lower end portion 18A of the accelerator pedal 18 in side view from the vehicle width direction. In other words, in side view, the front end portion of the upper wall 22 of the battery case 20 is disposed between the lower end portion 16A on the vehicle interior side of the dash panel 16 and the lower end portion 18A of the accelerator pedal 18.

[0025] Furthermore, a cross section 27 extending in the vehicle width direction is provided at the front end of the lower wall 24 side inside the battery case 20 (the part facing the opening 26 in the vertical direction). The cross section 27 is made of a metal plate bent into a roughly "L" shape in cross-section, and its front end 27A is joined to the front wall of the lower peripheral wall 25 by welding or the like. The detector 34 is positioned above the cross section 27. In other words, the detector 34 is positioned between the cross section 27 and the lid section 28.

[0026] Furthermore, a closed-section front cross member 14 extending in the vehicle width direction is installed between a pair of left and right rockers 13 (see Figure 1) on the lower side of the dash panel 16. The battery case 20 is mounted with its upper circumferential wall 23 close to the rear wall 14B of the front cross member 14, and its upper flange portion 23A is joined to the lower wall 14D of the front cross member 14 from below. In a side view, the upper surface 14A of the upper wall 14U of the front cross member 14 is approximately flush with the upper surface 22A of the upper wall 22 of the battery case 20 (see Figure 2).

[0027] The operation of the vehicle understructure 10 according to this embodiment, which has the configuration described above, will now be explained.

[0028] As described above, a battery case 20 is mounted on the lower part of the vehicle 12, with at least a portion of the upper wall 22 also serving as a floor panel. Inside the battery case 20 are a battery module 30 and a detector 34 for detecting voltage abnormalities in the battery module 30. An opening 26 is formed in the upper wall 22 of the battery case 20, allowing access to the detector 34, and a lid 28 is provided to open and close the opening 26.

[0029] Therefore, by removing the cover 28 (opening the opening 26), the worker can access the detector 34 through the opening 26. In this way, according to this embodiment, maintenance and replacement of the detector 34 can be performed without removing the battery case 20 from the vehicle 12.

[0030] Furthermore, in a side view from the vehicle width direction, the opening 26 is formed in the upper wall 22 of the battery case 20, which is located between the lower end 16A of the dash panel 16 on the passenger compartment side and the lower end 18A of the accelerator pedal 18. In other words, the opening 26 is formed in a part that is not easily accessible to the occupant (a part that cannot be accessed without removing the accelerator pedal 18). Therefore, there is no risk of the cover 28 being inadvertently removed from the passenger compartment by the occupant, thus ensuring safety.

[0031] Furthermore, a cross section 27 extending in the vehicle width direction is provided at the front end of the lower wall 24 side inside the battery case 20 (the part facing the opening 26 in the vertical direction). Therefore, compared to a case where the cross section 27 is not provided, the reduction in strength near the opening 26 in the battery case 20 can be effectively suppressed.

[0032] Furthermore, the upper surface 14A of the upper wall 14U of the front cross member 14, which is installed between a pair of left and right rockers 13 on the lower side of the dash panel 16, is substantially flush with the upper surface 22A of the upper wall 22 of the battery case 20. Therefore, compared to a case where the upper surface 14A of the upper wall 14U of the front cross member 14 and the upper surface 22A of the upper wall 22 of the battery case 20 are not substantially flush, it is possible to maximize both the suppression of the weight increase of the vehicle 12 and the reinforcement of the vicinity of the opening 26 in the battery case 20.

[0033] To explain in more detail, if the upper surface 14A of the upper wall 14U of the front cross member 14 is positioned higher than the upper surface 22A of the upper wall 22 of the battery case 20 (i.e., the size of the front cross member 14 is larger than shown in the illustration), then naturally the weight of the front cross member 14 will increase, and therefore the weight of the vehicle 12 will increase.

[0034] On the other hand, if the upper surface 14A of the upper wall 14U of the front cross member 14 is positioned lower than the upper surface 22A of the upper wall 22 of the battery case 20 (i.e., the size of the front cross member 14 is smaller than shown in the figure), the reinforcing effect on the vicinity of the opening 26 in the battery case 20 is reduced.

[0035] In the vehicle understructure 10 according to this embodiment, the upper surface 14A of the upper wall 14U of the front cross member 14 and the upper surface 22A of the upper wall 22 of the battery case 20 are substantially flush, so that the vicinity of the opening 26 in the battery case 20 can be effectively reinforced while suppressing an increase in the weight of the vehicle 12.

[0036] The vehicle understructure 10 according to this embodiment has been described above based on the drawings. However, the vehicle understructure 10 according to this embodiment is not limited to the illustrated version, and can be modified as appropriate without departing from the spirit of the present invention. For example, if the vehicle 12 is a left-hand drive electric vehicle, the detector 34 is located on the driver's side (left side) of the battery case 20, so the cover portion 28 (opening 26) is provided on the left side of the battery case 20, as shown by the dashed line in Figure 1. The front end of the cover portion 28 may also be attached to the upper wall 22 of the battery case 20 so as to be rotatable in the vehicle width direction as the axial direction. [Explanation of Symbols]

[0037] 10. Vehicle understructure 12 vehicles 13 Rocka 14 Front cross member 14A Top 16 Dash Panel 18. Accelerator pedal 20 Battery Cases 22 Upper wall 22A Top 26 Opening 27 Cross section 28 Lid 30 Battery Modules 34 detectors

Claims

1. A battery case mounted on the underside of the vehicle, with at least a portion of its upper wall also serving as a floor panel, The battery module housed inside the aforementioned battery case, A detector housed inside the battery case for detecting voltage abnormalities in the battery module, Equipped with, A vehicle understructure having an opening formed in the upper wall of the battery case that allows access to the detector, and a lid that can open and close the opening.

2. The vehicle understructure according to claim 1, wherein the opening is formed in the upper wall of the battery case, which is located between the dash panel that constitutes the front wall of the passenger compartment and the accelerator pedal, when viewed from the vehicle width direction in a side view.

3. The aforementioned opening is formed with the vehicle width direction as the longitudinal direction. The vehicle understructure according to claim 2, wherein the upper surface of the front cross member, which is installed between a pair of left and right rockers on the lower side of the dash panel of the vehicle, is flush with the upper surface of the upper wall of the battery case.

4. The aforementioned opening is formed with the vehicle width direction as the longitudinal direction. The vehicle understructure according to any one of claims 1 to 3, wherein a cross portion extending in the vehicle width direction is provided on the lower wall side inside the battery case and in a portion facing the opening in the vehicle vertical direction.

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