Vehicle bottom structure

Abstract

To reduce upward deflection of a share panel when an object collides with the share panel from a vehicle lower side.SOLUTION: A vehicle body structure includes a battery pack 16, an outer cross member 18 disposed below the battery pack 16 at intervals in a vehicle longitudinal direction, a plurality of reinforcing members 60, and a share panel 20. The share panel 20, the reinforcement member 60, and the lower wall 51 of the outer cross member 18 are fastened together with bolts 80. The reinforcing member 60 includes a body 61 having a recessed part 70 and provided with bolt through-holes 64 at an interval in the vehicle width direction, and a front flange 62 and a rear flange 63 positioned in front of and behind a non-bolt area 67 between the adjacent bolt through-holes 64 of the body 61. The non-bolt region 67 of the recessed portion 70 of the main body 61, the front flange 62, and the rear flange 63 are welded to the share panel 20. Both end portions 75 of the lower surface of the main body 61 in the front-rear direction are located outside both end portions 55 of the lower wall 51 of the outer cross member 18 in the front-rear direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This specification discloses a bottom structure for an electric vehicle that mounts a battery pack below the floor. [Background technology]

[0002] Electric vehicles such as battery electric vehicles (BEVs) have been known for some time. Electric vehicles are equipped with a battery pack that supplies power to a traction motor. The battery pack is mounted below the floor of the vehicle compartment.

[0003] Patent Document 1 discloses a battery case that is mounted under the floor of the passenger compartment of an electric vehicle and that houses a battery inside. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-87250 Summary of the Invention [Problem to be solved by the invention]

[0005] The electric vehicle includes a battery pack mounted below the floor, a plurality of outer cross members arranged at intervals in the longitudinal direction of the vehicle below the battery pack, and a share panel arranged below the plurality of outer cross members to cover the battery pack from below. The share panel forms the bottom surface of the vehicle below the floor.

[0006] The battery pack has a case that houses the battery modules. Each of the outer cross members has a hat-shaped cross section that opens upward, extends in the vehicle width direction, and is attached to the outer surface of the bottom plate of the battery pack case. The lower wall (web) of each outer cross member overlaps a shear panel, and they are fastened together with bolts. In other words, the shear panels are held at intervals in the vehicle fore-and-aft direction by the outer cross members.

[0007] When an object collides with a shear panel from below the vehicle, the shear panel will bend upward between the two fastening points (fastening points to the two outer cross members) in the vehicle's fore-and-aft direction. This could bring the shear panel close to the battery pack, potentially damaging it. It is desirable to reduce the amount of upward bending of the shear panel when an object collides with it from below the vehicle.

[0008] This specification discloses a vehicle underbody structure that can reduce upward deflection of a shear panel when an object collides with the shear panel from below the vehicle. [Means for solving the problem]

[0009] The vehicle undercarriage structure disclosed herein includes a battery pack having a case that houses a battery module and is mounted below a floor; multiple outer cross members located below a bottom plate of the case and spaced apart in the vehicle longitudinal direction; and a shear panel located below the multiple outer cross members and covering the bottom plate of the case. Each of the multiple outer cross members has a hat-shaped cross section that opens upward, extends in the vehicle width direction, and is attached to the outer surface of the bottom plate of the case. Reinforcing members extending in the vehicle width direction are located between the lower walls of the outer cross members and the shear panels. The shear panels, the reinforcing members, and the lower walls of the outer cross members are overlapped and fastened together with bolts spaced apart in the vehicle width direction. The reinforcing members include a main body having bolt through holes through which the bolts pass, and front and rear flanges that protrude in the vehicle longitudinal direction from non-bolt regions between adjacent bolt through holes of the main body. The vehicle longitudinal direction central portion of the main body of the reinforcing member has a recess extending in the vehicle width direction by removing weight from the upper surface. The non-bolt area in the recess of the main body of the reinforcing member, the front flange, and the rear flange are welded to the shear panel. Both vehicle longitudinal direction ends of the lower surface of the main body of the reinforcing member are located outward from both vehicle longitudinal direction ends of the lower wall of the outer cross member.

[0010] According to the above configuration, when an object collides with the share panel from below the vehicle, the distance between the fulcrums of the bending moment of the share panel is shorter due to the main bodies of each reinforcing member, whose both ends in the fore-and-aft direction of the vehicle are located outward from the outer cross members, compared to when the share panel is directly fastened to the lower walls of each outer cross member, and therefore the upward deflection of the share panel can be reduced.

[0011] Furthermore, with the above-described configuration, the non-bolt area in the recess of the main body of the reinforcing member, the front flange, and the rear flange are welded to the shear panel. Therefore, when an object strikes the shear panel from below the vehicle, the shear panel is restricted from moving toward the striking object relative to the reinforcing member, thereby reducing upward deflection of the shear panel.

[0012] According to the above configuration, the vehicle front-rear direction center portion of the upper surface of the main body of the reinforcing member (referred to as the reinforcing member main body) is hollowed out to form a recess extending in the vehicle width direction. Furthermore, while a front flange and a rear flange are present in front of and behind the non-bolt region of the reinforcing member main body, flanges may be omitted in front of and behind the bolt region (region with bolt through holes) of the reinforcing member main body. This allows the weight of the reinforcing member to be reduced.

[0013] In the vehicle bottom structure disclosed herein, the lower wall of the outer cross member has a convex portion protruding downward, the recess in the main body of the reinforcing member receives the convex portion of the outer cross member therein, the non-bolt area in the recess in the main body of the reinforcing member is filled with putty to fill the space between the inner surface of the recess and the outer surface of the convex portion of the outer cross member, and the convex portion of the outer cross member is detachable from the putty.

[0014] With this configuration, when an object collides with the shear panel from below the vehicle, the non-bolt area of ​​the main body of the reinforcing member (reinforcing member main body) is restricted from moving relative to the outer cross member, preventing the shear panel from approaching the battery pack. Furthermore, putty (gap filler) is placed between the inner surface of the recessed portion of the reinforcing member main body and the outer surface of the protruding portion of the outer cross member, preventing rattle between the non-bolt area of ​​the reinforcing member main body and the outer cross member. Furthermore, because the protruding portion of the outer cross member is detachable from the putty, the shear panel can be removed from the outer cross member by releasing the bolts connecting the outer cross member and the shear panel. This improves vehicle maintainability.

[0015] In the vehicle underbody structure of the present disclosure, the recess in the main body of the reinforcing member may include a first recess and a second recess provided in a central portion of the first recess in the vehicle longitudinal direction.

[0016] This configuration prevents putty in the recess of the main body of the reinforcing member (reinforcing member main body) from spilling outward during vehicle manufacture. That is, when placing putty in the recess of the reinforcing member main body during vehicle manufacture, softened putty is filled into the second recess, and the reinforcing member and shear panel are assembled to the outer cross member, so that the convex portion of the outer cross member penetrates into the putty in the second recess of the reinforcing member main body, and the putty then hardens. With the above configuration, when the convex portion of the outer cross member penetrates into the putty in the second recess of the reinforcing member main body, the putty spilling out of the second recess can be received by the first recess, thereby preventing the putty from spilling outward from the reinforcing member. [Effects of the Invention]

[0017] According to the technology disclosed in this specification, it is possible to reduce upward deflection of a shear panel when an object collides with the shear panel from below the vehicle. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a perspective view schematically illustrating an upper surface of a share panel of a vehicle according to an embodiment, showing an enlarged view of a part of a reinforcing member inside a dashed line. FIG. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 3] FIG. 10 is a cross-sectional view showing the bolt area of ​​a reinforcing member in another embodiment. [Figure 4] FIG. 10 is a cross-sectional view showing a non-bolt region of a reinforcing member in another embodiment. [Figure 5] 10A and 10B are diagrams illustrating a method of placing putty in a recess of a reinforcing member. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments will be described with reference to the drawings. In all drawings, equivalent elements are designated by the same reference numerals, and redundant explanations will be omitted. In the following description, unless otherwise specified, terms indicating directions and orientations, such as front, rear, left, right, up, down, etc., refer to directions and orientations relative to the vehicle. In each drawing, the arrow FR points forward, the arrow UP points upward, and the arrow RH points rightward.

[0020] Fig. 1 is a perspective view showing a schematic view of the top surface of a shared panel 20 of a vehicle 12, with an enlarged view of a portion of a reinforcing member 60 shown inside the dashed dotted line. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1, and also shows a battery pack 16 and floor 14 located above the shared panel 20. The vehicle 12 is an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or other electrically powered vehicle equipped with a battery pack 16 that supplies power to a motor (not shown) as a power source.

[0021] As shown in Figure 2, the battery pack 16 is mounted below the floor 14 of the vehicle compartment. The vehicle 12 is equipped with a shared panel 20 that covers the battery pack 16 from below. The shared panel 20 forms the bottom surface of the vehicle below the floor 14.

[0022] The battery pack 16 includes a plurality of battery modules 30 and a case 32. The battery module 30 includes a battery stack formed by stacking a large number of battery cells. The case 32 is the outer shell of the battery pack 16. The case 32 houses a plurality of battery modules 30 inside. The case 32 is composed of a lower case and an upper case. The lower case has, for example, a bathtub shape, and the upper case has, for example, an inverted bathtub shape (a shape resembling an upside-down bathtub). The upper case is fixed on top of the lower case. Figure 2 shows a bottom plate 36 of the lower case and a top plate 34 of the upper case.

[0023] A plurality of inner cross members 40 are attached to the upper surface of the bottom plate 36 of the case 32. The inner cross members 40 are disposed in the gaps between adjacent battery modules 30 and extend in the vehicle width direction (vehicle left-right direction). The inner cross members 40 are folded plate members with a hat-shaped cross section that are composed of a web 41, a pair of flanges 42 erected on both side ends of the web 41, and a pair of arms 43 extending outward from the tips of the pair of flanges 42. The arms 43 of the inner cross members 40 are joined to the upper surface of the bottom plate 36.

[0024] The vehicle 12 is equipped with a plurality of outer cross members 18. The outer cross members 18 are located below the bottom plate 36 of the case 32 and are spaced apart in the vehicle longitudinal direction. Each outer cross member 18 has a hat-shaped cross section that opens upward and extends in the vehicle transverse direction. The outer cross member 18 is a folded plate member composed of a lower wall 51 (web), a pair of flanges 52 erected on both side ends of the lower wall 51, and a pair of arms 53 extending outward from the tips of the pair of flanges 52. The arms 53 of the outer cross member 18 are joined to the underside of the portion of the bottom plate 36 to which the arms 43 of the inner cross member 40 are joined. A weld nut 82 is welded to the inside of the outer cross member 18.

[0025] The vehicle 12 is equipped with a plurality of reinforcing members 60 (reinforcements). The reinforcing members 60 are elongated, generally plate-shaped members extending in the vehicle width direction. The reinforcing members 60 are made by cutting, for example, metal extrusions, steel, resin, or the like. The reinforcing members 60 are arranged between the lower walls 51 of each outer cross member 18 and the share panels 20. As shown in FIG. 1 , the reinforcing members 60 are welded to the upper surfaces of the share panels 20 at intervals in the vehicle fore-and-aft direction. Each reinforcing member 60 is located inward in the vehicle width direction from the left end 28 and the right end 29 of the share panel 20, respectively.

[0026] The reinforcing member 60 includes a main body 61 (see the area inside the dashed dotted line in Figure 1 ) in which a plurality of bolt through holes 64 are provided at intervals in the vehicle width direction (vehicle left-right direction). The main body 61 has a recess 70 extending in the vehicle width direction by having the upper surface of the central portion in the front-to-rear direction lightened. The plurality of bolt through holes 64 are formed in the recess 70 of the main body 61. A bolt 80 (see Figure 2 ) is inserted from below the shear panel 20 and passes through each bolt through hole 64. In this specification, the main body 61 of the reinforcing member 60 is also referred to as a reinforcing member main body 61.

[0027] Hereinafter, the region of the reinforcing member body 61 where the bolt through holes 64 are provided will be referred to as a bolt region 66 (see the area inside the dashed line in Figure 1). Furthermore, the region between adjacent bolt through holes 64 of the reinforcing member body 61, i.e., the region of the reinforcing member body 61 where there are no bolt through holes 64, will be referred to as a non-bolt region 67. The AA cross section in Figure 2 shows the bolt regions 66 of two reinforcing members 60, and the balloon in the same figure shows a cross section of the non-bolt region 67 of one reinforcing member 60.

[0028] As shown in Fig. 1, the reinforcing member 60 has a front flange 62 and a rear flange 63 that protrude in the longitudinal direction of the vehicle from a non-bolt region 67 of a reinforcing member main body 61. Note that flanges are omitted in front of and behind the bolt region 66 of the reinforcing member main body 61. The non-bolt region 67 in the recess 70 of the reinforcing member main body 61, the front flange 62, and the rear flange 63 are welded to the top surface of the shear panel 20. In each figure, crosses indicate the locations of welding.

[0029] The shear panel 20 is a bottom plate of the vehicle and has a generally rectangular shape in a plan view with the longitudinal direction of the vehicle extending in the fore-and-aft direction. The shear panel 20 may be made of, for example, aluminum or high-tensile steel (steel with high tensile strength). As shown in FIG. 1 , the shear panel 20 has a front end 26, a rear end 27, a left end 28, and a right end 29. Although not shown, the front end 26, rear end 27, left end 28, and right end 29 are machined into desired shapes so that they can be attached to the vehicle's frame members. The front end 26, rear end 27, left end 28, and right end 29 of the shear panel 20 are attached to the frame members of the front, rear, left, and right parts of the vehicle, respectively.

[0030] 2, the shear panel 20, the reinforcing member 60, and the lower wall 51 of the outer cross member 18 are stacked and fastened together with a bolt 80. The bolt 80 passes through the shear panel 20, passes through a bolt through-hole 64 in the reinforcing member 60, passes through the lower wall 51 of the outer cross member 18, and is fastened to a weld nut 82 of the outer cross member 18. The reinforcing member 60 is provided with a series of fastening points (bolt regions 66) for the bolts 80 and nuts 82 spaced apart in the vehicle width direction.

[0031] As shown in FIG. 2, in each of the multiple reinforcing members 60, both vehicle longitudinal end portions 75 of the lower surface of the reinforcing member main body 61 are positioned outward from both vehicle longitudinal end portions 55 of the lower wall 51 of the outer cross member 18.

[0032] According to the embodiment described above, as shown in Fig. 2, when an object 110 on the road surface collides with the shear panel 20 and a collision load F is input to the shear panel 20, it is possible to reduce upward deflection of the shear panel 20. That is, when the shear panel 20 is directly fastened to the lower wall 51 of each outer cross member 18, the distance between the rear end 55 (reference symbol S1a in Fig. 2) of the front outer cross member 18 and the front end 55 (reference symbol S2a) of the rear outer cross member 18 becomes the fulcrum distance La of the bending moment of the shear panel 20 during an object collision.

[0033] On the one hand, according to the embodiment described above, a reinforcing member 60 is disposed between the shared panel 20 and the lower wall 51 of the outer cross member 18, and both end portions 75 in the vehicle longitudinal direction of the lower surface of the reinforcing member body 61 are located outward of both end portions 55 in the vehicle longitudinal direction of the lower wall 51 of the outer cross member 18. Therefore, the distance between the rear end 75 (reference sign S1 in FIG. 2) of the front reinforcing member body 61 and the front end 75 (reference sign S2) of the rear reinforcing member body 61 becomes the distance L between the fulcrums of the bending moment of the shared panel 20 during an object collision. In this case, the distance L between the fulcrums of the bending moment is shorter (L < La) compared to the case where the shared panel 20 is directly fastened to the outer cross member 18. Therefore, when the object 110 collides with the shared panel 20, the upward deflection of the shared panel 20 can be reduced.

[0034] Moreover, according to the embodiment described above, as shown inside the dashed-dotted line in FIG. 1, the non-bolt region 67 in the recess 70 of the reinforcing member body 61, the front flange 62, and the rear flange 63 are welded to the shared panel 20. When the object 110 collides with the shared panel 20 from below the vehicle, as shown by the arrow F1 in FIG. 2, a force causing the shared panel 20 to move away from the reinforcing member 60 is generated. That is, the shared panel 20 tends to move toward the collided object 110 side. However, according to the embodiment described above, since the reinforcing member 60 is welded to the shared panel 20, the movement of the shared panel 20 with respect to the reinforcing member 60 can be restricted. Therefore, the upward deflection of the shared panel 20 can be reduced.

[0035] Moreover, according to the embodiment described above, the central portion in the vehicle longitudinal direction of the upper surface of the reinforcing member body 61 is hollowed out to form a recess 70 extending in the vehicle width direction. Further, although the front flange 62 and the rear flange 63 exist in front of and behind the non-bolt region 67 of the reinforcing member body 61, the flanges are omitted in front of and behind the bolt region 66 of the reinforcing member body 61. Therefore, the weight of the reinforcing member 60 can be reduced.

[0036] Next, another embodiment will be described. Fig. 3 is a cross-sectional view showing the bolt region 66a of a reinforcing member 60 in this another embodiment, and Fig. 4 is a cross-sectional view showing the non-bolt region 67a of the reinforcing member 60 in this another embodiment. In this embodiment, the lower wall 51 of the outer cross member 18A has a protrusion 58 that protrudes downward. In addition, putty 86 (gap filler) is placed in the recess 70 of the non-bolt region 67a of the reinforcing member main body 61. The shape and other configurations of the reinforcing member 60 are the same as those of the embodiment described using Figs. 1 and 2.

[0037] The protrusion 58 of the outer cross member 18A is formed by bending the lower wall 51 so that it has a hat-shaped cross section. The outer cross member 18A has the same or nearly the same cross-sectional shape along the vehicle width direction.

[0038] The recess 70 of the reinforcing member main body 61 includes a first recess 71 and a second recess 72 provided in the center of the first recess 71 in the vehicle longitudinal direction (the center of the reinforcing member main body 61 in the short-side direction). The reinforcing member main body 61 has the same or approximately the same cross-sectional shape along the vehicle width direction.

[0039] Putty 86 is placed in the non-bolt area 67a of the recess 70 of the reinforcing member main body 61 to fill the gap between the inner surface of the recess 70 and the outer surface of the protrusion 58 of the outer cross member 18A. The protrusion 58 of the outer cross member 18A is detachable from the putty 86. This is achieved, for example, by applying a release agent to the outer surface of the protrusion 58 of the outer cross member 18A.

[0040] The effects of this other embodiment will now be described. As shown in Figure 2, when an object 110 collides with the shear panel 20 from below the vehicle and the shear panel 20 bends upward, a moment M1 is generated in the reinforcing member 60. This may cause the reinforcing member 60 to move relative to the lower wall 51 of the outer cross member 18 in the non-bolt region 67, as shown in the balloon in Figure 2, resulting in a large amount of upward bending of the shear panel 20.

[0041] However, according to this alternative embodiment, in the non-bolt region 67a, as shown in Fig. 4, the protrusion 58 of the outer cross member 18A penetrates into the putty 86 in the recess 70 of the reinforcing member main body 61, thereby restricting movement of the reinforcing member 60 relative to the lower wall 51 of the outer cross member 18. This reduces upward deflection of the shear panel 20.

[0042] In addition, putty 86 (gap filler) is placed between the inner surface of the recess 70 in the non-bolt area 67a of the reinforcing member main body 61 and the outer surface of the protrusion 58 of the outer cross member 18A, thereby suppressing rattling between the non-bolt area 67a of the reinforcing member main body 61 and the outer cross member 18A.

[0043] Furthermore, because the protrusions 58 of the outer cross member 18A are detachable from the putty 86, the shear panel 20 can be removed from the outer cross member 18A by releasing the fastening of the bolts 80 between the outer cross member 18A and the shear panel 20. This improves the ease of vehicle maintenance.

[0044] Here, a method for placing putty 86 in the recessed portion 70 of the reinforcing member 60 during vehicle manufacture will be described. Figure 5 shows steps (a) to (f) of placing putty 86 in the recessed portion 70 of the reinforcing member 60.

[0045] In step (a), a shear panel 20 having a plurality of reinforcing members 60 welded thereto is prepared.

[0046] In step (b), the softened putty 86 is poured into the recesses 70 in the non-bolt areas of the reinforcing member main body 61. At this time, it is advisable to place a damming member between the non-bolt areas and the bolt areas of the recesses 70 to prevent the putty 86 from flowing into the recesses 70 in the bolt areas of the reinforcing member main body 61.

[0047] In step (c), the spatula 112 is used to fill the putty 86 only in the second recess 72. Specifically, the spatula 112 is moved in the longitudinal direction of the reinforcing member 60 while being placed in contact with the underside of both ends of the first recess 71, thereby removing the putty 86 that has risen from the second recess 72.

[0048] In step (d), the putty 86 is hardened to the extent that it remains slightly flexible. At this time, if a damming member has been placed in step (b) above, it is advisable to remove the damming member.

[0049] In step (e), a release agent is applied to the protrusions 58 of the outer cross members 18A. Then, the shear panel 20, to which the reinforcing members 60 (filled with putty) are welded, is fastened to the outer cross members 18A with the bolts 80. At this time, the protrusions 58 of each outer cross member 18A penetrate into the putty 86 in the second recesses 72 of each reinforcing member 60. The putty 86 then hardens. As a result, recesses 88 corresponding to the protrusions 58 of the outer cross members 18A are formed in the putty 86.

[0050] According to this embodiment, when the protrusion 58 of the outer cross member 18A enters the putty 86 in the second recess 72 of the reinforcing member main body 61, the putty 86 that overflows from the second recess 72 can be received by the first recess 71. Therefore, the putty 86 can be prevented from overflowing outside the reinforcing member 60.

[0051] Furthermore, since a release agent is applied to the convex portions 58 of the multiple outer cross members 18A, as shown in step (f), when performing vehicle maintenance, the convex portions 58 of the outer cross member 18A can be detached from the putty concave portions 88, thereby removing the share panel 20 from the outer cross member 18A. [Explanation of symbols]

[0052] 12 vehicle, 14 floor, 16 battery pack, 18, 18A outer cross member, 20 share panel, 26 front end, 27 rear end, 28 left end, 29 right end, 30 battery module, 32 case, 34 top plate, 36 bottom plate, 40 inner cross member, 41 web, 42 flange, 43 arm, 51 lower wall (web), 52 flange, 53 arm, 55 end, 58 convex portion, 60 reinforcement member, 61 main body (reinforcement member main body), 62 front flange, 63 rear flange, 64 bolt through hole, 66, 66a bolt area, 67, 67a non-bolt area, 70 recess, 71 first recess, 72 second recess, 75 end, 80 bolt, 82 nut (weld nut), 86 putty (gap filler), 88 recess, 110 objects, 112 spatulas;

Claims

1. A vehicle underbody structure, a battery pack having a case for accommodating a battery module therein and mounted below the floor; a plurality of outer cross members located below the bottom plate of the case and spaced apart in the vehicle front-rear direction; a shear panel disposed below the outer cross members and covering the bottom plate of the case, Each of the outer cross members has a hat-shaped cross section that is open upward, extends in the vehicle width direction, and is attached to an outer surface of the bottom plate of the case, a reinforcing member extending in the vehicle width direction is disposed between the lower wall of each outer cross member and the share panel; the shear panel, the reinforcing member, and the lower wall of the outer cross member are overlapped and fastened together with bolts at intervals in the vehicle width direction, the reinforcing member includes a main body having a bolt through hole through which the bolt passes, and a front flange and a rear flange protruding in the vehicle front-rear direction from a non-bolt region of the main body between adjacent bolt through holes, a vehicle front-rear direction central portion of the main body of the reinforcing member has a recessed portion extending in the vehicle width direction by being lightened at an upper surface; the non-bolt region in the recess of the main body of the reinforcing member, the forward flange, and the aft flange are welded to the shear panel; Both ends of the lower surface of the main body of the reinforcing member in the vehicle longitudinal direction are located outward from both ends of the lower wall of the outer cross member in the vehicle longitudinal direction. A vehicle bottom structure characterized by:

2. 2. The vehicle underbody structure according to claim 1, The lower wall of the outer cross member has a protrusion that protrudes downward, the recess of the main body of the reinforcing member receives the protrusion of the outer cross member therein; a putty is placed in the non-bolt region of the recess of the main body of the reinforcing member to fill a gap between an inner surface of the recess and an outer surface of the protrusion of the outer cross member; The protrusion of the outer cross member is detachable from the putty. A vehicle bottom structure characterized by:

3. 3. The vehicle underbody structure according to claim 2, The recess in the main body of the reinforcing member is A first recess; a second recess provided in a vehicle front-rear direction central portion of the first recess, A vehicle bottom structure characterized by:

Images