JP5212892B2 - Lower body structure of the vehicle - Google Patents

Description

The present invention
A side sill located on the side of the vehicle body side of the floor panel and extending in the vehicle longitudinal direction; a side frame joined to the lower surface of the floor panel and extending in the vehicle longitudinal direction; and a gusset connecting the side sill and the side frame. The present invention relates to a lower body structure of a vehicle.

In this type of vehicle, when the vehicle has a side collision, the force from the side of the vehicle body is transmitted from the side sill to the side frame through the gusset, and when the vehicle has an offset collision, the force from the front side of the vehicle is transmitted through the gusset. This is communicated from the side frame to the side sill, which suppresses deformation of the vehicle body.
Conventionally, in the vehicle body lower part structure of the vehicle described above, the gusset is formed in a U-shaped cross-section with an open top with a front wall, a rear wall, and a bottom wall, and formed at both ends of the front and rear walls in the vehicle width direction. A flange facing in the vehicle width direction was overlapped and welded to the side sill and side frame separately, and a vertically facing flange formed on the upper end of the front and rear walls was overlapped on the lower surface of the floor panel and welded ( (See Patent Document 1 and Patent Document 2).
Japanese Patent Laid-Open No. 5-270448 Japanese Utility Model Publication No. 62-10185

According to the above-described conventional structure, the flange facing the top and bottom formed on the upper end of the front and rear walls of the gusset is overlapped and welded to the lower surface of the floor panel. This makes it difficult to change the distance between the upper and lower end portions of the front and rear walls, and provides an effect of transmitting a collision force from the side sill to the side frame or from the side frame to the side sill.
However, in order to obtain such an effect sufficiently, it is necessary to increase the connection strength between the upper and lower end portions of the front and rear walls by increasing the thickness of the floor panel, which increases the material cost and the weight. There was a problem.
The present invention has been made in view of the above circumstances, and an object of the present invention is to reduce the material cost while having a structure capable of sufficiently suppressing the deformation of the vehicle body at the time of a vehicle collision by increasing the rigidity of the gusset. It is possible to provide a vehicle body lower part structure that can be reduced in weight.

The feature of the present invention is that
A side sill located on the side of the vehicle body side of the floor panel and extending in the vehicle longitudinal direction; a side frame joined to the lower surface of the floor panel and extending in the vehicle longitudinal direction; and a gusset connecting the side sill and the side frame. A vehicle underbody structure,
The gusset includes a front wall located on the front side in the vehicle front-rear direction, a rear wall located on the rear side, and a bottom wall located between the front and rear walls, and an upper end portion of the front wall and the rear wall Ri is the upper portion and the floor panel is connected by a separate coupling member tare,
The connecting member is reinforcement;
The gusset comprises an upper open cross-section U-shaped gusset body provided with the front and rear walls and a bottom wall, and a reinforcement for connecting the upper end portion of the front wall and the upper end portion of the rear wall,
The edge of the reinforcement inner side in the vehicle width direction is brought close to the side frame,
The edge of the reinforcement in the vehicle width direction is close to the side sill . (Claim 1)

According to this configuration, the upper end portion of the front wall of the gusset and the upper end portion of the rear wall are connected by the connecting member separate from the floor panel. The interval between the upper end portions can be made difficult to change. That is, it is possible to increase the rigidity of the gusset so that the collision force can be easily transmitted from the side sill to the side frame or from the side frame to the side sill at the time of the collision, and the deformation of the vehicle body can be sufficiently suppressed. In addition, in order to sufficiently obtain such an effect, it is only necessary to increase the thickness of the connecting member separate from the floor panel, and it is not necessary to increase the thickness of the floor panel, thereby reducing the material cost. Can be reduced in weight.
In addition, it is possible to make it difficult for the spacing between the upper ends of the front and rear walls of the gusset to be changed by reinforcement at the time of a side collision or an offset collision of the vehicle. In other words, the rigidity of the gusset can be increased by the reinforcement so that the collision force can be easily transmitted from the side sill to the side frame or from the side frame to the side sill at the time of the collision, and deformation of the vehicle body can be sufficiently suppressed.
And the rigidity of a gusset can be strengthened more and the space | interval of the upper end parts of the front-and-back wall of a gusset can be made harder to change at the time of the side collision of a vehicle, or an offset collision. (Claim 1)

In the present invention,
A front flange on the vehicle front side provided in the reinforcement is overlapped and welded to the upper end portion of the front wall of the gusset from the vehicle rear side,
The rear flange on the vehicle rear side provided in the reinforcement is overlapped and welded to the upper end of the rear wall of the gusset from the vehicle front side,
When the reinforcement is spaced downward from the lower surface of the floor panel, the following effects can be achieved. (Claim 2 )

A front flange on the vehicle front side provided in the reinforcement is overlapped and welded to the upper end portion of the front wall of the gusset from the vehicle rear side, and a rear flange on the vehicle rear side provided in the reinforcement is connected to the rear wall of the gusset. Since it is welded and joined to the upper end of the vehicle from the front side of the vehicle, a strong (high) flange surface can be arranged along the vehicle width direction, and the gusset rigidity can be further increased. The distance between the upper and lower ends of the front and rear walls of the gusset can be made more difficult to change during a vehicle side collision or an offset collision. (Claim 2 )

In the present invention,
The side frame includes a pair of left and right side walls extending in the vehicle front-rear direction, and a brace lined up with the gusset in the vehicle width direction is installed between the pair of left and right side walls. The force applied to the frame can be supported by the braces in the side frame, and the deformation of the vehicle body can be further suppressed. (Claim 3 )

In the present invention,
The brace includes a brace front wall portion and a brace rear wall portion that are respectively bridged between a pair of left and right side walls of the side frame,
Arranging the front wall of the gusset and the front wall portion of the brace in the vehicle width direction,
When the rear wall of the gusset and the rear wall portion of the brace are arranged in the vehicle width direction, the force applied to the side frame via the front wall and the rear wall of the gusset at the time of a side collision of the vehicle is applied to the front wall portion of the brace and the rear wall of the brace. Can be supported by each part (ie, the force transmitted from the front wall of the gusset can be supported by the front wall part of the brace, and the force transmitted from the rear wall of the gusset can be supported by the rear wall part of the brace) The deformation of the vehicle body can be further suppressed. (Claim 4 )

In the present invention,
Between the floor tunnel located on the inner side in the vehicle width direction than the side frame and the side frame, a cross member lined up with the gussets and braces in the vehicle width direction is erected,
The cross member includes a cross member front wall portion and a cross member rear wall portion spanned between the floor tunnel and the side frame,
The front wall of the gusset, the brace front wall and the cross member front wall are arranged in the vehicle width direction,
When the rear wall of the gusset, the rear wall portion of the brace, and the rear wall portion of the cross member are arranged in the vehicle width direction, the following action can be achieved. (Claim 5 )

The force applied to the side frame through the front wall of the gusset during a side collision of the vehicle can be supported by the front wall portion of the brace and the front wall portion of the cross member, and the force applied to the side frame through the rear wall of the gusset It can be supported by the rear wall part and the cross member. Since the cross member is interposed between the floor tunnel and the side frame, the force at the time of the collision can be easily transmitted to the floor tunnel, and the deformation of the vehicle body can be further suppressed. (Claim 5 )

According to the present invention,
Providing a vehicle lower body structure that can reduce the material cost and reduce the weight of the vehicle while reducing the cost of the vehicle body at the time of a vehicle collision by strengthening the gusset rigidity. We were able to.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of a lower body structure of a vehicle located on the lower side of the center pillar 9 on the right side of the vehicle body, as viewed obliquely from the front upper side of the vehicle. FIG. 2 is a perspective view of the lower body structure of the vehicle viewed from the front lower side of the vehicle. FIG.
As shown in both figures, a side sill 10 that is positioned on the vehicle body side W2 (vehicle width direction outer side W2) of the floor panel 1 and extends in the vehicle front-rear direction, and joined to the lower surface 1K of the floor panel 1 in the vehicle front-rear direction. A side frame 20 that extends and a gusset 30 that connects the side sill 10 and the side frame 20 are provided to form a lower body structure of the automobile. In FIG. 1, reference numeral 7 is an opening for a front door, and 8 is an opening for a rear door. The vehicle body lower structure and the vehicle body lower structure of the automobile located below the center pillar 9 on the left side of the vehicle body are symmetrical.

[Structure of floor panel 1]
As shown in FIGS. 3 and 5, the floor panel 1 includes a flange 1F1 that rises upward on one side of the vehicle width direction outer side W2, and this flange 1F1 is connected to the side sill inner panel 11 of the side sill 10 from the vehicle width direction inner side W1. They are overlapped and welded together. In the left and right central part of the automobile, a floor tunnel 60 having a lower open cross section provided with one side wall 61, another side wall 62, and an upper wall 63 extends in the vehicle front-rear direction. The other side portion 1F2 is overlapped and welded to the flange 61F formed at the lower end portion of the one side wall 61 of the floor tunnel 60 from below.

  Further, as shown in FIGS. 1, 3 and 4, a pair of front and rear seat brackets 2 having a hat shape in the shape of a lower opening are welded to the upper surface 1J of the floor panel 1 by welding. The seat bracket 2 extends in the vehicle width direction W, and the rear seat bracket 2 is positioned on the inner side W1 of the center pillar 9 in the vehicle width direction. The front seat bracket 2 has a front end portion of a pair of left and right seat rails connected to a lower end portion of the seat. The rear end portion of the pair of left and right seat rails has a rear end portion. Mounted and connected. Of the rear seat bracket 2, the seat bracket portion on which the rear end portion of the right side (vehicle width direction outer side W <b> 2) seat rail is placed and connected is configured as a base-like bulged portion 3 bulging upward. Yes.

[Structure of side sill 10]
The side sill 10 includes a side body outer panel 12 that includes the side sill inner panel 11 having a hat-shaped cross section that is open on the vehicle outer side (vehicle width direction outer side W2) and a bottom wall 12T that is bent toward the vehicle inner side (vehicle width direction inner side W1). A bottom sill 12K and a side sill reinforcement 14 having a hat-shaped cross section that is located between the lower end 12K and is open in the vehicle width direction (W1 in the vehicle width direction) are joined in the vehicle width direction W. That is, the flange 14F at the lower end of the side sill reinforcement 14 is sandwiched between the flange 11F at the lower side of the side sill inner panel 11 and the flange 12F at the lower end 12K of the side body outer panel 12 and welded. The lower end of the center pillar 9 is welded to the side sill 10.

[Structure of side frame 20]
As shown in FIGS. 2, 3, and 6, the side frame 20 is formed in a hat shape having an open top with a pair of left and right side walls 22, 24 extending in the vehicle front-rear direction and a bottom wall 23. In the longitudinal section, the height of the pair of left and right side walls 22 and 24 is set to be longer than the width of the bottom wall 23, and the pair of left and right side walls 22 and 24 are formed so as to expand upward. , 24 are welded to the lower surface 1K of the floor panel 1.

  As shown in FIGS. 4 and 5, flange portions 22F1 and 24F1 of both side walls 22 and 24 of the side frame 20 located in the vehicle width direction inner side W1 of a gusset 30 to be described later are shallowly bulged downward in a trapezoidal cross section. . As a result, a gap S is formed between the flange portions 22F1 and 24F1 and the floor panel 1, and the coating liquid is allowed to flow through the gap S in the painting process at the time of manufacturing the vehicle body lower structure.

  The side frame 20 extends in the vehicle front-rear direction so that a first frame portion 20A located on the inner side W1 of the center pillar 9 is orthogonal to the vehicle width direction W (see FIG. 2). A second frame portion 20B having a predetermined length on the vehicle front side Fr with respect to the portion 20A extends obliquely forward on the inner side W1 in the vehicle width direction. The first frame portion 20A and the second frame portion 20B are welded to each other.

[Structure of gusset 30]
As shown in FIGS. 2, 3, 7, and 8, the gusset 30 includes a front wall 31 positioned on the front side in the vehicle front-rear direction, a rear wall 32 positioned on the rear side, and a space between the front and rear walls 31, 32. And a reinforcement 35 (corresponding to a connecting member) for connecting the upper end of the front wall 31 and the upper end of the rear wall 32 below the floor panel 1. That is, the gusset 30 includes an upper open section U-shaped gusset body 34 (see FIG. 7) provided with the front and rear walls 31, 32 and the bottom wall 33, an upper end portion of the front wall 31, and an upper end portion of the rear wall 32. And a reinforcement 35 (see FIG. 8). Reference numeral 36 provided on the bottom wall 33 is a jig hole for welding work.

  Further, the upper edge of the one side part 31S1, 32S1 of the front and rear walls 31, 32 in the vehicle width direction W1 and the upper edge of the other side part 31S2, 32S2 are positioned at the same position in the vertical direction, and the other side part 31S2 , 32S2 is positioned at the middle in the vertical direction of the front and rear walls 31, 32, and the bottom wall 33 of the gusset 30 is configured as an inclined wall positioned on the upper side in the vehicle width direction outer side W2. The upper edge of one side part 31S1, 32S1 and the upper edge of the other side part 31S2, 32S2 are close to the lower surface 1K of the floor panel 1 in the vehicle width direction inner side W1 of the front and rear walls 31, 32.

  Then, as shown in FIG. 5, a flange 33F1 formed at the end of the bottom wall 33 of the gusset 30 on the inner side W1 in the vehicle width direction is overlapped and welded to the bottom wall 23 of the side frame 20 from below. A flange 33F2 formed at the end of the bottom wall 33 of the bottom wall 33 in the vehicle width direction is overlapped and welded to the bottom wall 13 of the side sill inner panel 11 from below.

  Further, as shown in FIGS. 6 and 7, flanges 31F1 and 32F1 formed on one side portions 31S1 and 32S1 of the front and rear walls 31 and 32 in the vehicle width direction inner side W1 are used as side walls 22 of the side frames 20 on the outer side W2 in the vehicle width direction. The flanges 31F2 and 32F2 formed on the other side portions 31S2 and 32S2 of the front and rear walls 31 and 32 are overlapped and welded to the side sill inner panel 11 from the vehicle width direction inner side W1. It is.

  As shown in FIG. 8, the reinforcement 35 is formed in a U-shaped cross section with the upper open side, and the front flange 35F1 of the vehicle front side Fr of the reinforcement 35 is connected to the upper end portion of the front wall 31 of the gusset 30 on the vehicle rear side. The rear flange 35F2 on the vehicle rear side is overlapped and welded to the upper end portion of the rear wall 32 of the gusset 30 from the vehicle front side Fr. The reinforcement 35 is positioned parallel to the floor panel 1 (may be substantially parallel) and is spaced downward from the lower surface 1K of the floor panel 1 (see FIG. 5).

  5, the edge 35E1 of the reinforcement 35 on the inner side W1 in the vehicle width direction is brought close to the side wall 22 of the outer side W2 of the side frame 20 in the vehicle width direction, and the edge of the outer side W2 of the reinforcement 35 in the vehicle width direction. 35E2 is brought close to the side sill inner panel 11 of the side sill 10. The edge 35E1 of the reinforcement 35 on the inner side W1 in the vehicle width direction is more in the vehicle width direction than the edge 22E2 on the outer side W2 of the flange 22F formed at the upper end of the side wall 22 of the side frame 20 on the outer side W2 in the vehicle width direction. The end portion of the reinforcement 35 in the vehicle width direction inner side W1 and the flange 22F formed on the upper end portion of the side wall 22 of the side frame 20 in the vehicle width direction outer side W2 overlap each other in plan view. The gusset 30 having the above structure is located below the pedestal-shaped bulging portion 3 on which the rear end portion of the right side (vehicle width direction outer side W2) seat rail is placed and connected.

[Structure of brace 40]
As shown in FIGS. 3, 5, and 6, a brace 40 aligned with the gusset 30 in the vehicle width direction W is provided between a pair of left and right side walls 22 and 24 of the side frame 20. The brace 40 includes a brace front wall portion 41 and a brace rear wall portion 42 that are bridged between a pair of left and right side walls 22 and 24 of the side frame 20.

The flange 41F1 formed at the end of the brace front wall 41 on the vehicle width direction inner side W1 and the flange 42F1 formed at the end of the brace rear wall 42 on the vehicle width direction inner side W1 are connected to the vehicle of the side frame 20. Overlap and weld-join to the inner surface of the side wall 24 of the width direction inner side W1,
A flange 41F2 formed at the end of the outer width W2 of the brace front wall 41 and a flange 42F2 formed at the end of the outer width W2 of the rear wall 42 of the brace are arranged in the vehicle width direction of the side frame 20. It is welded and joined to the inner surface of the side wall 22 of the outer side W2.

  As shown in FIG. 6, a flange 41F2 formed at the end of the brace front wall 41 at the vehicle width direction outer side W2, and a flange 31F1 formed at one side 31S1 of the gusset front wall 31 at the vehicle width direction inner side W1 Is sandwiching the side wall 22 of the side frame 20 on the outer side W2 in the vehicle width direction, and these three members are integrally welded together in the sandwiched state. In this way, the front wall 31 of the gusset and the front wall portion 41 of the brace are arranged in a straight line in the vehicle width direction W.

  Further, the flange 42F2 formed at the end of the brace rear wall portion 42 in the vehicle width direction outer side W2 and the flange 32F1 formed in the one side portion 32S1 of the rear wall 32 of the gusset 30 in the vehicle width direction include a side frame. The side wall 22 of the vehicle width direction outer side 20 of 20 is pinched | interposed, and the three parties are integrally weld-joined in the pinched state. In this manner, the rear wall 32 of the gusset 30 and the rear wall portion 42 of the brace are arranged in a straight line in the vehicle width direction W.

  The brace front wall portion 41 and the brace rear wall portion 42 have the same shape, and their height dimension is substantially the same as the height dimension of the gusset 30. The upper edge of both is close to the lower surface 1K of the floor panel 1, and the lower edge is close to the inner surface of the bottom wall 23 of the side frame 20.

[Structure of cross member 50]
As shown in FIGS. 2, 3, and 6, the gusset 30 and the brace 40 are arranged in the vehicle width direction W between the floor tunnel 60 and the side frame 20 located on the inner side W <b> 1 in the vehicle width direction than the side frame 20. A cross member 50 is installed. The cross member 50 includes a cross member front wall portion 51 and a cross member rear wall portion 52 which are respectively bridged between the floor tunnel 60 and the side frame 20, and a bottom wall 53 which is positioned on the upper side in the vehicle width direction inner side W1. It is formed in the cross-sectional hat shape of the upper open side provided with.

The flanges 51F1 and 52F1 formed at the ends of the cross member front wall portion 51 and the cross member rear wall portion 52 at the vehicle width direction outer side W2 are overlapped with the side wall 24 of the side frame 20 at the vehicle width direction inner side W1 and welded. And
The flange 51F2 formed at the upper end of the cross member front wall 51 and the cross member rear wall 52 is superimposed on the lower surface 1K of the floor panel 1 and welded,
A flange 53F1 formed at the end of the bottom wall 53 of the cross member 50 in the vehicle width direction inner side W1 is overlapped with a flange 61F formed at the lower end portion of the one side wall 61 of the floor tunnel 60 in the vehicle width direction outer side W2 from below. Welding and
A flange 53F2 formed at the end of the bottom wall 53 of the cross member 50 in the vehicle width direction is overlapped and welded to the bottom wall 23 of the side frame 20 (the bottom wall 23 of the first frame portion 20A). .

  As shown in FIG. 6, the flange 51F1 formed at the end of the cross member front wall 51 on the vehicle width direction outer side W2 and the flange 41F1 formed at the end of the brace front wall 41 on the vehicle width direction inner side W1 The side wall 24 of the side frame 20 in the vehicle width direction inner side W1 is sandwiched, and these three members are integrally welded and joined in the sandwiched state. In this way, the front wall 31, the brace front wall portion 41, and the cross member front wall portion 51 of the gusset 30 are arranged in a straight line in the vehicle width direction W.

  The flange 52F1 formed at the end of the cross member rear wall 52 in the vehicle width direction outer side W2 and the flange 42F1 formed at the end of the brace rear wall 42 in the vehicle width direction inner side W1 The side wall 24 of the inner side W1 in the vehicle width direction is sandwiched, and these three members are integrally welded together in the sandwiched state. In this manner, the rear wall 32, the brace rear wall portion 42, and the cross member rear wall portion 52 of the gusset 30 are arranged in a straight line in the vehicle width direction W.

[Another embodiment]
(1) One or two or more beads extending in the vehicle width direction W may be formed on the reinforcement 35 to increase the strength of the reinforcement 35 against the force from the side of the vehicle body.
(2) One or two or more beads extending in the vehicle width direction W are formed on the brace front wall portion 41 and the brace rear wall portion 42, respectively, and the strength of both is increased against the force from the side of the vehicle body. There may be. Further, a connecting member for connecting the brace front wall portion 41 and the brace rear wall portion 42 may be provided. The present invention can also be applied to a structure in which only one of the brace front wall portion 41 and the brace rear wall portion 42 is provided.
(3) The gusset 30 is formed in a rectangular tube shape whose axis is along the vehicle width direction W, and the upper end portion of the front wall 31 and the upper end portion of the rear wall 32 of the gusset 30 are formed on the upper wall portion of the gusset 30. It may be connected.

The perspective view which looked at the lower part of the body of the car from the diagonally front upper side of the car The perspective view which looked at the lower part structure of the car from the front lower part of the car A longitudinal sectional view of the underbody structure of an automobile as seen from the front side of the vehicle Longitudinal sectional view of the underbody structure of an automobile viewed from the side of the vehicle Longitudinal sectional view of the gusset and surrounding structure as seen from the front of the vehicle Cross-sectional plan view of the underbody structure of an automobile Perspective view of gusset body Reinforce perspective view

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Floor panel 1K The lower surface 10 of the floor panel 1 Side sill 20 Side frame 22, 24 Side wall (side frame side wall)
30 Gusset 31 Front wall (Gusset front wall)
32 Rear wall (back wall of gusset)
33 Bottom wall (Bottom wall of gusset)
34 Gusset body 35 Connecting member (Reinforce)
35E1 edge (the edge inside the vehicle width direction of the reinforcement)
35E2 edge (reinforce edge on the outside in the vehicle width direction)
35F1 front flange (front flange on the front side of the vehicle provided at the reinforcement)
35F2 rear flange (rear flange on the rear side of the vehicle provided in the reinforcement)
40 Brace 41 Brace front wall portion 42 Brace rear wall portion 50 Cross member 51 Cross member front wall portion 52 Cross member rear wall portion 60 Floor tunnel W Vehicle width direction W2 Vehicle body side side (vehicle width direction outside)

Claims (5)

A side sill located on the side of the vehicle body side of the floor panel and extending in the vehicle longitudinal direction; a side frame joined to the lower surface of the floor panel and extending in the vehicle longitudinal direction; and a gusset connecting the side sill and the side frame. A vehicle underbody structure,
The gusset includes a front wall located on the front side in the vehicle front-rear direction, a rear wall located on the rear side, and a bottom wall located between the front and rear walls, and an upper end portion of the front wall and the rear wall Ri is the upper portion and the floor panel is connected by a separate coupling member tare,
The connecting member is reinforcement;
The gusset comprises an upper open cross-section U-shaped gusset body provided with the front and rear walls and a bottom wall, and a reinforcement for connecting the upper end portion of the front wall and the upper end portion of the rear wall,
The edge of the reinforcement inner side in the vehicle width direction is brought close to the side frame,
A vehicle body lower part structure in which an end edge of the reinforcement in the vehicle width direction is close to the side sill . A front flange on the vehicle front side provided in the reinforcement is overlapped and welded to the upper end portion of the front wall of the gusset from the vehicle rear side,
The rear flange on the vehicle rear side provided in the reinforcement is overlapped and welded to the upper end of the rear wall of the gusset from the vehicle front side,
Underbody structure of a vehicle according to claim 1, wherein the reinforcement are moved away downwardly from the lower surface of the floor panel. The lower part of the vehicle body according to claim 1 or 2 , wherein the side frame includes a pair of left and right side walls extending in the vehicle front-rear direction, and a brace arranged in parallel with the gusset in the vehicle width direction is provided between the pair of left and right side walls. Construction. The brace includes a brace front wall portion and a brace rear wall portion that are respectively bridged between a pair of left and right side walls of the side frame,
Arranging the front wall of the gusset and the front wall portion of the brace in the vehicle width direction,
The vehicle body lower part structure according to claim 3 , wherein the rear wall of the gusset and the rear wall part of the brace are arranged in the vehicle width direction. Between the floor tunnel located on the inner side in the vehicle width direction than the side frame and the side frame, a cross member lined up with the gussets and braces in the vehicle width direction is erected,
The cross member includes a cross member front wall portion and a cross member rear wall portion spanned between the floor tunnel and the side frame,
The front wall of the gusset, the brace front wall and the cross member front wall are arranged in the vehicle width direction,
The vehicle body lower part structure according to claim 4 , wherein the rear wall of the gusset, the rear wall portion of the brace, and the rear wall portion of the cross member are arranged in the vehicle width direction.

Images