Vehicle underbody structure

Abstract

The invention provides a vehicle underbody structure. In the vehicle bottom structure, the protective panel is made of metal. In addition, the protective panel includes a panel portion and a panel reinforcing member. The panel part is in a flat plate shape. The panel reinforcing member is provided on the panel portion in a protruding manner. In addition, the panel reinforcing member extends in a straight line. The panel reinforcing component is of a hollow structure. Further, the panel portion and the panel reinforcing member are integrally formed.

Description

TECHNICAL FIELD

[0001] In the present specification, a vehicle bottom structure is disclosed. BACKGROUND

[0002] On a battery electric vehicle (BEV; a pure electric vehicle), a battery pack is mounted. For example, the battery pack is disposed under the floor of the passenger compartment.

[0003] For example, in Japanese Patent Application Publication No. 2023-46945, a protective panel called a share panel is provided below the battery pack. The protective panel is a panel member made of metal, unlike a bottom panel made of resin.

[0004] For example, sometimes a vehicle will drive onto a curb. Also, sometimes a vehicle will travel on a bumpy road surface. In such cases, the vehicle can experience what is called "belly scraping". That is, there is a case where the bottom surface of the vehicle comes into contact with the road surface. At this time, a load can be input from the road surface to the protective panel provided on the bottom surface of the vehicle. SUMMARY

[0005] To strengthen the rigidity of the protective panel, it is conceivable to mount a reinforcing member on the protective panel. Also, to mount the reinforcing member on the protective panel, a fastener such as a bolt can be used. As a result of the reinforcing member and the fastener being added, the weight of the protective panel can increase.

[0006] Therefore, in the present specification, a vehicle bottom structure is disclosed that can improve the rigidity of a protective panel while suppressing an increase in weight.

[0007] In the present specification, a vehicle bottom structure is disclosed. The vehicle bottom structure is configured with a battery pack at the bottom of a vehicle.

[0008] A protective panel is disposed below the battery pack. The protective panel covers the battery pack.

[0009] The protective panel is made of metal.

[0010] Also, the protective panel has a panel portion and a panel reinforcing member.

[0011] The panel portion is flat plate-shaped.

[0012] The panel reinforcing member is protrusively provided on the panel portion. Also, the panel reinforcing member extends linearly.

[0013] The panel reinforcing member is a hollow structure.

[0014] Further, the panel portion and the panel reinforcing member are integrally formed.

[0015] According to the above structure, since the panel portion and the panel reinforcement component are integrally molded, the weight increase caused by fasteners can be avoided. Furthermore, since the panel reinforcement component has a hollow structure, the weight increase can be suppressed compared to using solid materials.

[0016] In addition, in the above structure, flange portions that are fastened to the battery pack may also be provided at both ends of the panel in the vehicle width direction.

[0017] In this case, a height difference structure is formed by the panel portion and the flange portion. Through this height difference structure, the flange portion is positioned higher than the panel portion.

[0018] The panel reinforcement component protrudes upwards from the panel.

[0019] Furthermore, an adhesive is provided at the upper end of the panel reinforcement component.

[0020] The protruding height of the panel reinforcement component is above the height difference formed by the height difference structure.

[0021] According to the above structure, by making the panel reinforcement component more prominent than the height difference structure, the upper end of the panel reinforcement component can be bonded to the bottom surface of the battery pack.

[0022] Furthermore, in the aforementioned structure, the panel reinforcement component can also extend in the longitudinal direction of the vehicle.

[0023] A battery pack consists of multiple battery cells and a battery casing. The battery casing houses the multiple battery cells.

[0024] The battery housing has a tray section on which multiple battery cells are configured.

[0025] A housing reinforcement component is provided on the bottom wall of the tray section.

[0026] The housing reinforcement extends in the longitudinal direction of the vehicle.

[0027] The upper end of the panel reinforcement component is bonded to the bottom wall of the tray.

[0028] The panel reinforcement and the housing reinforcement are arranged in a straight line along the vehicle height direction.

[0029] According to the above structure, a housing reinforcement member is disposed directly above the panel reinforcement member. Therefore, the panel reinforcement member and the housing reinforcement member are integrated to bear the load from the road surface.

[0030] Furthermore, in the above structure, the panel reinforcement component protrudes upward from the panel portion.

[0031] Fastening holes can also be drilled in the thickness direction on the panel reinforcement components.

[0032] On the panel, there is a maintenance hole. The maintenance hole is coaxial with the fastening hole. In addition, the maintenance hole exceeds the diameter of the fastener head.

[0033] According to the above structure, the protrusion of the fastener head from the protective panel can be prevented. As a result, the reduction in the vehicle's aerodynamic characteristics can be suppressed.

[0034] Furthermore, in the above structure, multiple panel reinforcement members may be formed on the protective panel at intervals.

[0035] In this case, the spacing between adjacent panel reinforcement members can also be less than the width of the panel reinforcement member.

[0036] According to the above structure, the area covered by the panel reinforcement component is wider than the uncovered area.

[0037] According to the vehicle bottom structure disclosed in this specification, the rigidity of the protective panel can be improved while suppressing weight increase. Attached Figure Description

[0038] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, wherein like symbols denote like elements, and wherein:

[0039] Figure 1 This is an exploded perspective view illustrating the vehicle bottom structure according to this embodiment.

[0040] Figure 2 A 3D view of the protective panel.

[0041] Figure 3 for Figure 1 Sectional view III-III in the diagram.

[0042] Figure 4 Sectional view III-III showing a first other example of the vehicle's underbody structure.

[0043] Figure 5 A perspective view showing a first example of a protective panel. Detailed Implementation

[0044] exist Figures 1 to 5 The image illustrates the vehicle bottom structure according to this embodiment. Additionally, in... Figures 1 to 5 In this diagram, the vehicle's forward / backward direction is represented by the FR axis. The vehicle's width is represented by the RW axis. The vertical direction is represented by the UP axis. The FR axis sets the forward direction as positive. The RW axis sets the rightward direction as positive. The UP axis sets the vertical direction as positive.

[0045] 1. Overall Structure

[0046] exist Figure 1 The diagram shows an exploded perspective view of the vehicle's underbody structure. The vehicle underbody structure according to this embodiment is mounted on a battery electric vehicle (BEV). Furthermore, the vehicle underbody structure according to this embodiment includes a battery pack 10, a protective panel 20, and a frame 30.

[0047] A battery pack 10 is located at the bottom of the vehicle. Furthermore, a protective panel 20 is located below the battery pack 10. That is, the lower part of the battery pack 10 is covered by the protective panel 20. The battery pack 10 and the protective panel 20 are supported by a frame 30.

[0048] The protective panel 20 protects the battery pack 10 from the impact of uneven road surfaces or curbs. The protective panel 20 is made of metal. For example, as described later, the protective panel 20 is made of aluminum.

[0049] To improve the rigidity of the protective panel 20, a panel reinforcing member 24 is provided on the protective panel 20. The panel reinforcing member 24 has a hollow structure. Therefore, compared with the case where the panel reinforcing member 24 is made of solid material, the increase in weight of the protective panel can be suppressed. Furthermore, the panel reinforcing member 24 is integrally formed with the panel portion 22. That is, fasteners for mounting the panel reinforcing member 24 to the panel portion 22 are not required. As a result, the increase in weight of the protective panel can also be suppressed.

[0050] 2. Framework

[0051] The frame 30 is a frame-shaped skeleton component. For example, the frame 30 supports the entire circumference of the battery pack 10. For example, the frame 30 and the battery pack 10 constitute the floor of the passenger compartment. In addition, a seat bracket 39 is attached to the frame 30.

[0052] Reference Figure 3 The frame 30, for example, has a hollow structure. For example, the cross-section of the frame 30 is rectangular. A fastening hole 41A is perforated in the bottom wall 41 of the frame 30. The fastening hole 41A extends through the thickness direction of the bottom wall 41.

[0053] A welding nut 40 is provided inside the frame 30. The welding nut 40 is coaxial with the fastening hole 41A. As described later, the fastening holes 14A and 17A of the battery pack 10 are axially aligned with the fastening hole 41A. Furthermore, the fastening hole 76A of the housing bracket 70 is also axially aligned with the fastening hole 41A. And bolts 45 (fasteners) are screwed into these fastening holes 14A, 17A, 41A, and 76A. Thus, the battery pack 10 and the protective panel 20 are fastened to the frame 30.

[0054] 3. Battery pack

[0055] Reference Figure 1 The battery pack 10 is a large, box-shaped component. For example, the battery pack 10 is mounted on the floor of the vehicle compartment. The battery pack 10 supplies power to a rotary motor (not shown), which serves as the drive source for the vehicle.

[0056] The battery pack 10 is supported by the frame 30. (See reference) Figure 1 , Figure 3 For example, multiple fastening holes 14A and 17A are formed in the upper flange 14 and lower flange 17 of the battery pack 10. The upper flange 14 and lower flange 17 are formed across the entire circumference of the battery pack 10. Furthermore, the fastening holes 14A and 17A are formed across the entire circumference of the upper flange 14 and lower flange 17. Therefore, the battery pack 10 is securely supported on the frame 30 across its entire circumference.

[0057] Reference Figure 3 The battery pack 10 includes a battery casing 11 and multiple battery cells 50. The battery casing 11 houses the battery cells 50. The battery cells 50 are, for example, composed of nickel-metal hydride batteries, lithium-ion batteries, and all-solid-state batteries.

[0058] Reference Figure 1 , Figure 3 The battery housing 11 includes an upper housing 12 and a lower housing 15. The lower housing 15 includes a tray portion 16 and a lower flange 17. The lower housing 15 is made of a metal panel, such as an aluminum panel. For example, the lower housing 15 is formed by stamping. A plurality of battery cells 50 are arranged in the tray portion 16.

[0059] The lower flange 17 is disposed around the periphery of the tray portion 16. For example, the lower flange 17 surrounds the tray portion 16 in a manner that spans the entire circumference. In addition, the lower flange 17 is provided at the upper end of the tray portion 16.

[0060] The upper housing 12 is the cover portion of the battery housing 11. For example, the upper housing 12 is made of a metal panel such as an aluminum panel. For example, the upper housing 12 is formed by stamping.

[0061] The upper housing 12 includes a cover portion 13 and an upper flange 14. The cover portion 13 covers the tray portion 16 of the lower housing 15. The upper flange 14 is disposed on the periphery of the cover portion 13. For example, the upper flange 14 is provided at the lower end of the cover portion 13. The upper flange 14 is provided in a manner that spans the entire circumference of the cover portion 13.

[0062] In addition, refer to Figure 1 Thus, a housing bracket 70 is mounted on the outer surface (exposed surface) of the lower housing 15. For example, the housing bracket 70 is configured to span the entire length of the side of the lower housing 15.

[0063] Reference Figure 3 The housing bracket 70 has an S-shaped cross-section. The housing bracket 70 includes a flange 74, a flange 76, and a longitudinal plate 72. The lower flange 74 and the upper flange 76 are connected to the longitudinal plate 72.

[0064] Flange 74 is joined to the bottom wall 16A of tray portion 16. For example, flange 74 is welded to bottom wall 16A. A fastening hole 76A is perforated in flange 76. The fastening hole 76A is configured to be coaxial with the fastening hole 17A of lower flange 17.

[0065] A gap is formed between the side wall 16B of the tray section 16 and the longitudinal plate 72 of the housing bracket 70, extending along the vehicle width direction. A weld nut 59 is disposed in this gap. A fastening hole 74A is perforated in the flange 74. The weld nut 59 is configured coaxially with the fastening hole 74A. As described later, the weld nut 59 is a fastener for the protective panel 20. That is, the protective panel 20 is fastened to the frame 30 via the housing bracket 70.

[0066] Inside the battery housing 11, in addition to the battery unit 50, a housing reinforcement member 52 is also housed. The housing reinforcement member 52 has, for example, a cap-shaped cross-section. Furthermore, the housing reinforcement member 52 extends within the tray portion 16 in the vehicle's longitudinal direction. The housing reinforcement member 52 has a pair of flanges 52A, 52A and a pair of ribs 52B, 52B.

[0067] A pair of flanges 52A, 52A are mounted on the bottom wall 16A of the tray portion 16. For example, flanges 52A, 52A are welded to the bottom wall 16A. Rib 52B is erected relative to flange 52A.

[0068] As described later, the housing reinforcement 52 and the panel reinforcement 24 of the protective panel 20 are arranged in a straight line along the vehicle height direction. Furthermore, the upper end face 24B of the panel reinforcement 24 abuts against the bottom wall 16A of the tray portion 16 via adhesive 25. Therefore, the housing reinforcement 52 and the panel reinforcement 24 of the protective panel 20 are integrated. For example, when a load is input from the road surface upwards, the load will be borne by both the housing reinforcement 52 and the panel reinforcement 24 of the protective panel 20. Thus, compared to the case where the reinforcement is a single unit, load-bearing capacity is improved.

[0069] 4. Protective panel

[0070] Reference Figure 1 The protection panel 20 is positioned below the battery pack 10. That is, the protection panel 20 covers the battery pack 10 from below. The protection panel 20 is also referred to as the shared panel.

[0071] The protective panel 20 serves two functions: protecting the battery pack 10 and improving the vehicle's aerodynamic characteristics. To improve the vehicle's aerodynamic characteristics, a cover is sometimes installed under the vehicle. Since rigidity is not generally required for the cover, it is typically made of resin. In contrast, the protective panel 20 requires a certain degree of rigidity to protect the battery pack 10. Therefore, the protective panel 20 is made of metal. For example, the protective panel 20 is made of aluminum.

[0072] The protective panel 20 includes a panel portion 22, a panel reinforcing member 24, and a flange portion 26. The panel portion 22 is a flat plate. The flange portions 26 are formed at both ends of the panel portion 22 in the vehicle width direction. The flange portions 26 are fastened to the battery pack 10 via a housing bracket 70. For example, the panel portion 22 and the flange portions 26 are formed by stamping a flat aluminum plate. Alternatively, as described later, the panel portion 22 and the flange portions 26 are integrally formed by aluminum extrusion.

[0073] The panel portion 22 and the flange portion 26 have a height difference structure. (Refer to...) Figure 3 The flange portion 26 is positioned higher than the panel portion 22. This height difference structure ensures that the panel portion 22 separates from the bottom wall 16A of the tray portion 16 when the flange portion 26 is fastened to the housing bracket 70. When a load from the road surface is applied to the panel portion 22, deformation may occur. Even in such cases, because the panel portion 22 is separated from the bottom wall 16A, deformation of the bottom wall 16A following the panel portion 22 is prevented.

[0074] The flange 26 has a maintenance hole 26A and a fastening hole 26B. (See reference...)Figure 3 The maintenance hole 26A is located directly below the bolt 45. The bolt 45 can be removed through the maintenance hole 26A. That is, with the protective panel 20 fastened to the battery pack 10, the battery pack 10 can be removed from the frame 30.

[0075] The fastening holes 74A and 59 of the housing bracket 70 are axially aligned with the fastening hole 26B. The protective panel 20 is secured to the housing bracket 70 by screwing the bolt 29 into the fastening holes 26B, 74A, and 59. In other words, the protective panel 20 is secured to the battery pack 10 via the housing bracket 70.

[0076] Reference Figure 1 A panel reinforcement member 24 is provided on the protective panel 20. The panel reinforcement member 24 is protruding from the panel portion 22. That is, the panel reinforcement member 24 protrudes upward from the panel portion 22. For example, the panel reinforcement member 24 is provided on the upper surface of the panel portion 22. The upper surface of the panel portion 22 is flush with the bottom wall 16A of the battery pack 10 (see reference). Figure 3 Opposite.

[0077] Reference Figure 2 The panel reinforcement member 24 extends in a straight line. For example, the panel reinforcement member 24 extends in the vehicle's longitudinal direction. For example, the panel reinforcement member 24 extends from the front end of the panel portion 22 to the rear end. Furthermore, a plurality of panel reinforcement members 24 are provided on the protective panel 20 at intervals in the vehicle width direction.

[0078] In addition, although Figure 2 In this design, a panel reinforcement member 24 extends in the longitudinal direction of the vehicle, but the panel reinforcement member 24 can also be provided in other ways. For example, the panel reinforcement member 24 can also extend in a straight line along the width direction of the vehicle. In this case, multiple panel reinforcement members 24 are provided on the protective panel 20 at intervals in the longitudinal direction of the vehicle.

[0079] The panel reinforcement component 24 has a hollow structure. For example, in Figure 2 At the lower right, an enlarged view of the panel reinforcement member 24 is shown. The panel reinforcement member 24 is trapezoidal in shape when viewed from the front. Furthermore, the panel reinforcement member 24 is provided with ribs 24A extending in the vehicle height direction. For example, multiple ribs 24A are provided in the panel reinforcement member 24.

[0080] The panel reinforcement member 24 and the panel portion 22 are integrally formed. For example, the panel reinforcement member 24 and the panel portion 22 are integrally formed by aluminum extrusion. Alternatively, the panel reinforcement member 24 and the panel portion 22 are integrally formed by die casting.

[0081] To enable the integral molding of such metal material, the front and rear ends of the panel reinforcement member 24 are opened. That is, the panel reinforcement member 24 has a mold outlet. Furthermore, the panel reinforcement member 24 extends in a straight line. For example, in aluminum extrusion processing, the length direction of the panel reinforcement member 24 is the extrusion direction. In addition, by making the mold have a height difference structure, the panel portion 22 and the flange portion 26 can be integrally molded. That is, by integrally molding the panel portion 22, the panel reinforcement member 24, and the flange portion 26, the protective panel 20 is formed.

[0082] Reference Figure 2 , Figure 3 The upper end surface 24B of the panel reinforcement member 24 is a flat surface. For example, the upper end surface 24B is parallel to the panel portion 22. An adhesive 25 is disposed on the upper end surface 24B. For example, double-sided tape is attached to the upper end surface 24B.

[0083] Here, the protrusion height H2 from the panel portion 22 to the upper end surface 24B is greater than or equal to the height difference H1 between the panel portion 22 and the flange portion 26. Therefore, when the flange portion 26 is fastened to the flange 74 of the housing bracket 70, the adhesive 25 on the upper end surface 24B can be bonded to the bottom wall 16A of the tray portion 16. In other words, the upper end surface 24B of the panel reinforcing member 24 is bonded to and abuts against the bottom wall 16A of the tray portion 16 via the adhesive 25.

[0084] Furthermore, when the flange 26 is fastened to the flange 74 of the housing bracket 70, the housing reinforcement member 52 and the panel reinforcement member 24 of the battery housing 11 are arranged in a straight line along the vehicle height direction. In addition, as described above, the upper end face 24B of the panel reinforcement member 24 abuts against the bottom wall 16A of the tray portion 16. That is, the housing reinforcement member 52 and the panel reinforcement member 24 are integrated.

[0085] For example, when a load is applied from the road onto the panel reinforcement 24, both the housing reinforcement 52 and the panel reinforcement 24 will bear the load. Compared to the case where the reinforcement is a single unit, the load-bearing capacity of the battery pack 10 is improved.

[0086] 5. First other examples of vehicle underbody structure

[0087] exist Figure 4 The image shows a first other example of a vehicle underbody structure. In this example, the method by which the panel reinforcement member 24 abuts against the bottom wall 16A differs from that described above. Other structures differ due to their relationship with... Figures 1 to 3 The same applies, therefore the explanation will be omitted below.

[0088] existFigure 4 In this example, instead of adhesive 25, panel reinforcement member 24 is bolted. A fastening hole 24B1 is perforated in the thickness direction on the upper end face 24B. Furthermore, a fastening hole 16A1 is perforated on the bottom wall 16A of the tray portion 16. Further, a fastening hole 52A1 is also perforated on the flange 52A of the housing reinforcement member 52. Additionally, a weld nut 62 is provided on the flange 52A. The weld nut 62 is coaxial with the fastening hole 52A1.

[0089] When the protective panel 20 is fastened to the housing bracket 70, the fastening holes 24B1, 16A1, and 52A1 are arranged coaxially. In this state, the bolts 60 are screwed into the fastening holes 24B1, 16A1, and 52A1, as well as the welding nuts 62. As a result, the panel reinforcement member 24 abuts against the bottom wall 16A of the tray portion 16.

[0090] Here, a maintenance hole 22A is perforated in the panel portion 22. The maintenance hole 22A is coaxial with the fastening hole 24B1 of the panel reinforcement member 24. Furthermore, the diameter of the maintenance hole 22A exceeds the diameter of the head of the bolt 60 (fastener).

[0091] The maintenance hole 22A is provided through the perforation, allowing the head of the bolt 60 to be housed within the panel reinforcement member 24. In other words, it prevents the head of the bolt 60 from protruding downwards from the panel portion 22. This, in turn, prevents a decrease in aerodynamic characteristics associated with bolt fastening.

[0092] 6. Other examples of protection panels

[0093] exist Figure 5 The image shows a first other example of the protective panel 20. In this example, the width W1 and spacing W2 of the panel reinforcement members 24 differ from those described above. Other structures differ due to their similarity to... Figure 2 The same applies, therefore the explanation will be omitted below.

[0094] Multiple panel reinforcement members 24 are arranged on the panel portion 22 at intervals along the vehicle width direction. Here, the spacing W2 of the panel reinforcement members 24 is smaller than the width W1 of the panel reinforcement members 24. The spacing W2 represents the distance between adjacent panel reinforcement members 24, 24. The width W1 represents the dimension of the panel reinforcement members 24 in the vehicle width direction.

[0095] With this structure, the panel portion 22 is covered by the panel reinforcing member 24 by more than 50%. That is, the area covered by the panel reinforcing member 24 is wider than the uncovered area. As a result, the rigidity of the protective panel 20 is improved.

Claims

1. A vehicle underbody structure, wherein a battery pack is disposed at the bottom of the vehicle, wherein, A protective panel covering the battery pack is disposed below the battery pack. The protective panel is made of metal and has the following features: Flat panel section; A panel reinforcement member is provided protrudingly on the panel portion and extends in a straight line. The panel reinforcement component has a hollow structure. The panel portion and the panel reinforcement component are integrally formed.

2. The vehicle bottom structure as described in claim 1, wherein, Flange portions that are fastened to the battery pack are provided at both ends of the panel in the vehicle width direction. A height difference structure is formed by the panel portion and the flange portion, with the flange portion positioned higher than the panel portion. The panel reinforcement component protrudes upward from the panel portion. Furthermore, an adhesive is disposed at the upper end of the panel reinforcing member. The protruding height of the panel reinforcement component is above the height difference formed by the height difference structure.

3. The vehicle bottom structure as described in claim 2, wherein, The panel reinforcement component extends in the longitudinal direction of the vehicle. The battery pack includes: Multiple battery units; A battery casing that houses multiple battery cells. The battery casing includes a tray portion on which multiple battery cells are configured. On the bottom wall of the tray section, a housing reinforcement member extending in the vehicle's longitudinal direction is disposed. The upper end of the panel reinforcement component is bonded to the bottom wall of the tray portion. The panel reinforcement and the housing reinforcement are arranged in a straight line along the vehicle height direction.

4. The vehicle bottom structure as described in claim 1, wherein, The panel reinforcement component protrudes upward from the panel portion. The panel reinforcement member has fastening holes perforated in the thickness direction. A maintenance hole is perforated on the panel, the maintenance hole being coaxial with the fastening hole and exceeding the diameter of the head of the fastener.

5. The vehicle underbody structure as described in any one of claims 1 to 4, wherein, The panel reinforcement members are formed in multiple spaced-apart portions on the protective panel. The spacing between adjacent panel reinforcement members is less than the width of the panel reinforcement member.

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