JP6128324B2 - Lower body structure of the vehicle - Google Patents

Description

  The present invention relates to a lower vehicle body structure of a vehicle, and more particularly to a lower vehicle body structure of a vehicle provided with a tunnel portion that protrudes upward from a vehicle width direction center portion of a floor panel and extends in the vehicle body longitudinal direction.

Conventionally, an upward projecting tunnel portion is formed in the vehicle width direction center portion of a vehicle floor panel so as to extend in the longitudinal direction of the vehicle body in order to insert an exhaust system, a propeller shaft, and the like.
It is known that vibrations and noise (road noise) are generated on the floor panel of a vehicle due to resonance of a suspension device during traveling, cavity resonance of a tire, and the like.
Therefore, the vehicle body rigidity in the vehicle width direction has been improved by joining the tunnel portion and the side sill via the floor cross member.

  The lower vehicle body structure of a vehicle disclosed in Patent Document 1 includes a tunnel portion that protrudes into a vehicle compartment on a floor panel, and a floor cross member that is disposed across the tunnel portion, and corresponds to the floor cross member in the vehicle body longitudinal direction. A first tunnel member for connecting the floor cross member in a substantially straight line and a second tunnel member for connecting the floor cross member in a curved shape along the side surface of the tunnel part are disposed in the middle of the tunnel portion. . As a result, the tunnel portion and the first tunnel member constitute a substantially annular structure, thereby suppressing deformation of the tunnel portion, and the second tunnel member constituting a reinforcing member that continues in the vehicle width direction of the tunnel portion. As a result, the torsional rigidity of the vehicle body is improved.

In the lower body structure of the vehicle, a tunnel side member that forms a closed cross-sectional portion that extends in the longitudinal direction of the vehicle body in cooperation with the floor panel is formed on the vehicle width direction outer side portion of the tunnel portion.
Normally, the tunnel side member forms a lattice-like closed cross-section structure in cooperation with the floor cross member and the side sill, thereby reducing the vibration and noise in the passenger compartment. It is provided for the purpose of a load path function that protects the passenger compartment space by distributing and transmitting the applied collision load toward the rear of the vehicle body.

JP 2012-11856 A

The lower body structure of a vehicle disclosed in Patent Document 1 can improve the rigidity of the vehicle body by dispersing the closed cross-section structure in the longitudinal direction of the vehicle body and the vehicle width direction, and can reduce the collision load and reduce the vibration.
In general, as disclosed in Patent Document 1, as the rigidity of the vehicle body structure is improved, the number of parts to be mounted around the floor panel and the thickness of each component member are increased, and the weight of the vehicle body may increase. There is.

The main needs required for vehicles include fuel consumption, vehicle production costs, and the like in addition to the above-described safety and driving comfort. Here, as an effective solution that can improve the fuel consumption and the production cost of the vehicle at the same time, the weight of the vehicle body can be reduced.
However, since the structural members around the floor panel contribute to ensuring safety and improving ride comfort during running as rigid members of the vehicle body, if these rigid members are simply omitted or made thinner, the weight of the vehicle body Even if the weight of the vehicle can be reduced, there may be a problem in terms of vibration and noise in the passenger compartment.
As a result of the inventor's verification of the shape of the constituent members constituting the closed cross section around the floor panel with respect to the above problem, even when the tunnel side member is formed in the open cross section, the vibration noise suppression function and the load in the vehicle interior It was found that the pass function can be sufficiently secured.

  An object of the present invention is to provide a lower vehicle body structure and the like of a vehicle that can reduce the vehicle body weight while ensuring a vibration noise suppression function and a load path function.

The lower body structure of the vehicle according to claim 1 is a floor panel that extends rearward from the lower end of a dash panel that partitions the engine room and the passenger compartment, and projects upward from a center portion in the vehicle width direction of the floor panel and extends rearward of the vehicle body. In a lower body structure of a vehicle including a tunnel portion, a tunnel side that extends in a vehicle body longitudinal direction at an outer portion in a vehicle width direction of the tunnel portion and projects downward from the floor panel to form an open cross-section portion having an open top surface A member is provided, and the end side tunnel side member of the tunnel side members is formed so that a downward projecting amount decreases toward the end side, and is provided below the bottom of the end side tunnel side member. A closed cross-section portion is formed in cooperation with the end portion side reinforcing member .

  In the lower vehicle body structure of the vehicle according to claim 1, since the tunnel side member extending in the longitudinal direction of the vehicle body is provided on the vehicle width direction outer side portion of the tunnel portion, the vibration noise suppressing function for reducing vibration and noise generated in the vehicle interior is provided. In addition, it is possible to secure a load path function that disperses and transmits the collision load applied from the front to the rear part of the vehicle body at the time of the front collision.

According to a second aspect of the present invention, in the first aspect of the invention, the end side tunnel side member has a front tunnel side member formed so that a downward projecting amount decreases toward the front of the vehicle body. The side reinforcing member has a front reinforcing member .
The invention of claim 3 is the invention of claim 2, characterized in that a bead portion extending in the longitudinal direction of the vehicle body is formed at the bottom of the front tunnel side member.

According to a fourth aspect of the present invention, in the first aspect of the present invention, a kick-up portion connected to the rear end of the floor panel is provided, and the end side tunnel side member protrudes downward toward the rear of the vehicle body. A rear tunnel side member formed to reduce the amount, the end side reinforcing member has a rear side reinforcing member, and the closed cross-section portion formed in cooperation with the rear side reinforcing member is It is characterized by being formed to extend to the vicinity of the kick-up portion.

According to a fifth aspect of the present invention, there is provided a floor panel that extends rearward from the lower end of the dash panel that partitions the engine room and the vehicle compartment, and a tunnel portion that protrudes upward from a center portion in the vehicle width direction of the floor panel and extends rearward of the vehicle body. In the lower vehicle body structure of the vehicle, a tunnel side member extending in the vehicle front-rear direction is provided at a vehicle width direction outer side portion of the tunnel portion, and the tunnel side member has a vehicle width direction outer end portion in the vehicle width direction of the floor panel. A seat bracket for attaching a seat device to the tunnel side member is provided, which is joined to the inner end portion and protrudes downward from the floor panel to form an open top surface open section , and the seat bracket includes at least , And a flange for joining to the vehicle width direction inner side end portion of the floor panel and the vertical wall portion of the tunnel portion, respectively. It is characterized by having a part.
According to a sixth aspect of the present invention, in the fifth aspect of the present invention, there is provided a connecting member for connecting a vehicle width direction inner side end portion of the floor panel and a vertical wall portion of the tunnel portion, and a flange portion for the connecting member of the seat bracket. The lower body structure of a vehicle according to claim 5, wherein the joint is joined to the connecting member.

According to the first aspect of the present invention, since the vibration side noise suppression function and the load path function can be secured by the tunnel side member having an open cross-sectional shape, the vibration and noise in the vehicle interior can be reduced, and the vehicle interior space is protected at the time of a front collision. can do. Further, since the tunnel side members to form an open cross section of the open top shape, as possible out to reduce the upper surface corresponding material steel plate of the tunnel side members.
Moreover, by forming a closed cross-section using the bottom of the end side tunnel side member, the impact load can be received by the end side tunnel side member in the event of a collision, reducing the impact of collision into the vehicle interior. it can.

According to the invention of claim 2, by forming the closed cross-section portion using the bottom of the front tunnel side member, it is possible to receive an impact load by the front tunnel side member at the time of a front collision, and The impact of collision can be reduced.
According to the invention of claim 3, the proof strength of the front tunnel side member in the front-rear direction can be increased, and the influence of the collision into the vehicle compartment can be further reduced.

  According to the invention of claim 4, during the front collision, the impact load applied to the front tunnel side member is distributed while being transmitted to the rear part of the vehicle body via the rear tunnel side member, thereby reducing the influence of the collision into the vehicle interior. be able to. Further, at the time of a rear collision, the impact load can be received by the rear tunnel side member, and the influence of the collision into the vehicle compartment can be reduced.

According to the fifth aspect of the present invention, the vibration side noise suppression function and the load path function can be secured by the tunnel side member having an open cross-sectional shape, so that vibration and noise in the passenger compartment can be reduced, and the passenger compartment space is protected at the time of a front collision. can do. In addition, since the tunnel side member forms an open cross section with the upper surface open, the material steel plate corresponding to the upper surface of the tunnel side member can be reduced, and the outer end in the vehicle width direction of the tunnel side member is the vehicle width of the floor panel. Since it joins to a direction inner side edge part, it can assemble without changing a conventional work process.
In addition, the vehicle body rigidity in the vehicle width direction can be increased using the seat bracket, and the tunnel portion can be prevented from falling in the vehicle width direction at the time of a side collision.
According to the sixth aspect of the present invention, the seat bracket can be installed using the connecting member for preventing the tunnel portion from falling in the vehicle width direction.

It is the figure which looked at the lower body structure of the vehicle which concerns on Example 1 of this invention from diagonally back. It is a top view of FIG. It is the III-III sectional view taken on the line of FIG. It is the IV-IV sectional view taken on the line of FIG. It is the VV sectional view taken on the line of FIG. It is the VI-VI sectional view taken on the line of FIG. It is the VII-VII sectional view taken on the line of FIG. It is the VIII-VIII sectional view taken on the line of FIG. It is a perspective view of the 1st bracket. It is a top view of the 1st bracket. It is a perspective view of a 3rd bracket. It is a top view of a 3rd bracket.

  Hereinafter, modes for carrying out the present invention will be described based on examples. In this embodiment, the front-rear direction of the vehicle is referred to as the front-rear direction, and the left-right direction of the vehicle is described as the left-right direction.

Hereinafter, Example 1 of the present invention will be described with reference to FIGS.
As shown in FIGS. 1 and 2, in this embodiment, a lower vehicle body structure of a vehicle V including a floor panel 1, a tunnel portion 2, a pair of left and right tunnel side members 3 and the like will be described as an example.
The vehicle V includes a pair of left and right side sills 4 joined to the left and right end portions of the floor panel 1 and extending in the front-rear direction, a front door hinge pillar 5 extending upward from the front end portion of each side sill 4, and the upper ends of the hinge pillars 5. 1 is a monocoque type passenger car that includes a front pillar 6 that extends rearward and upward, a center pillar 7 that extends upward from a middle part in the front-rear direction of each side sill 4, a kick-up portion K, and the like. In addition, since the lower vehicle body structure of the vehicle V is a left-right symmetric structure, the left side structure will be mainly described below.

The steel panel floor panel 1 forms the bottom surface of the passenger compartment S and is divided into left and right portions with the tunnel portion 2 interposed therebetween. The floor panel 1 is configured to extend rearward from the lower end of the dash panel 8 to the kick-up portion K.
The dash panel 8 that partitions the engine room E and the vehicle compartment S is joined to the front end of the floor panel 1 and is disposed so as to move upward as it extends forward. A pair of left and right front side frames (not shown) are joined to the front surface of the dash panel 8 so as to extend forward.
On the lower surface of the floor panel 1, a floor frame 11 is provided that extends in the front-rear direction at an intermediate portion between the side sill 4 and the tunnel portion 2. The floor frame 11 is formed in a hat shape in cross section, and forms a closed cross section that extends from the lower end portion of the dash panel 8 to the vicinity of the kick-up portion K in cooperation with the lower surface of the floor panel 1.

  As shown in FIGS. 1, 2, and 5, a floor cross member 12 that connects the side sill 4 and the tunnel portion 2 is installed on the upper surface of the floor panel 1 at a position in the front-rear direction corresponding to the center pillar 7. . The floor cross member 12 has a substantially hat-shaped cross section, a bead portion 12f that is recessed in the upper wall portion 12a, an outer flange portion 12b on the outer side in the vehicle width direction, and an inner flange on the inner side in the vehicle width direction. A portion 12c, a front flange portion 12d, and a rear flange portion 12e are provided. The floor cross member 12 has an outer flange portion 12b joined to the vertical wall portion 4a on the inner side in the vehicle width direction of the side sill 4, and an inner flange portion 12c joined to the vertical wall portion 2a on the outer side in the vehicle width direction of the tunnel portion 2, The flange portion 12d and the rear flange portion 12e are joined to the upper surface of the floor panel 1, thereby forming a closed cross-section portion that extends in the vehicle width direction in cooperation with the upper surface of the floor panel 1.

  As shown in FIGS. 1 to 7, the steel-made tunnel portion 2 protrudes upward from the center portion in the vehicle width direction of the floor panel 1 and extends rearward from the lower end portion of the dash panel 8 to the kick-up portion K. Is formed. An exhaust pipe (not shown) or the like is disposed below the tunnel portion 2. A tunnel side member 3 is provided between the tunnel portion 2 and the floor panel 1.

Next, the tunnel side member 3 will be described.
As shown in FIGS. 1 to 8, the tunnel side member 3 has an approximately cross-sectional opening that is opened upward by extending the outer portion in the vehicle width direction of the vertical wall portion 2 a of the tunnel portion 2 below the floor panel 1. It is formed in a letter shape. The tunnel side member 3 includes a front tunnel side member 21 corresponding to the front side portion of the passenger compartment S, an intermediate tunnel side member 22 positioned rearward of the front tunnel side member 21, and a rear side of the intermediate tunnel side member 22. And a rear tunnel side member 23 of the side portion.

As shown in FIGS. 3 and 8, the front tunnel side member 21 corresponding to the front side portion of the end side tunnel side member includes a vertical wall portion 21a on the inner side in the vehicle width direction and a vertical wall portion 21b on the outer side in the vehicle width direction. And a bottom portion 21c that connects the lower ends of the vertical wall portions 21a and 21b, and an overhang portion 21d that protrudes horizontally from the upper end portion of the vertical wall portion 21b outward in the vehicle width direction. The front tunnel side member 21 is formed so that the height position of the bottom portion 21c increases toward the front of the vehicle body so that the amount of downward protrusion decreases toward the front of the vehicle body.
The bottom portion 21c is provided with a downward protruding bead portion 21e extending in the front-rear direction.
Below the bottom 21c, a front reinforcing member 24 having a substantially U-shaped cross section among the end side reinforcing members is provided so as to cover from the front end of the floor panel 1 to the rear end of the front tunnel side member 21. The closed cross-section C1 extending in the front-rear direction is configured in cooperation with the lower surface of the bottom 21c.
The overhanging portion 21d is overlap-bonded to the inner portion of the floor panel 1 in the vehicle width direction.

As shown in FIGS. 4 to 6 and 8, the intermediate tunnel side member 22 includes a vertical wall portion 22a on the inner side in the vehicle width direction, a vertical wall portion 22b on the outer side in the vehicle width direction, and both vertical wall portions 22a and 22b. A bottom portion 22c that connects the lower end portions, and an overhang portion 22d that projects horizontally from the upper end portion of the vertical wall portion 22b outward in the vehicle width direction are provided. The bottom 22c is formed so as to be at a substantially constant height position.
The overhang portion 22d is overlap-bonded to the inner portion of the floor panel 1 in the vehicle width direction.

  A connecting member 26 that partially covers the upper portion of the intermediate tunnel side member 22 by connecting the vertical wall portion 2a of the tunnel portion 2 and the inner portion in the vehicle width direction of the floor panel 1 to the front portion of the intermediate tunnel side member 22. Is provided. The connecting member 26 is formed of a substantially U-shaped plate member in plan view, the front portion and the rear portion are joined to the tunnel portion 2 and the floor panel 1, and the intermediate portion is joined only to the tunnel portion 2. Yes.

As shown in FIGS. 7 and 8, the rear tunnel side member 23 corresponding to the rear portion of the end side tunnel side member includes a vertical wall portion 23a on the inner side in the vehicle width direction and a vertical wall portion 23b on the outer side in the vehicle width direction. And a bottom portion 23c that connects the lower ends of the vertical wall portions 23a and 23b, and an overhang portion 23d that protrudes horizontally from the upper end portion of the vertical wall portion 23b outward in the vehicle width direction. The rear tunnel side member 23 is formed so that the height position of the bottom portion 23c increases toward the rear of the vehicle body so that the downward projecting amount decreases toward the rear of the vehicle body.
The bottom 23c is provided with an upward protruding bead 23e extending in the front-rear direction.
A rear reinforcing member 25 having a substantially U-shaped cross section among the end side reinforcing members is provided below the bottom portion 23c so as to cover from the front end portion of the rear tunnel side member 23 to the vicinity of the kick-up portion K. A closed cross-section C2 extending in the front-rear direction is configured in cooperation with the lower surface of the bottom 23c.
The overhang portion 23d is overlap-bonded to the inner portion of the floor panel 1 in the vehicle width direction.

  With the above configuration, the open section C3 having an open top surface along the tunnel portion 2 and having two ridge lines is formed between the tunnel portion 2 and the floor panel 1, so that an edge formed by the two ridge lines is formed. The buckling of the open section C3 can be suppressed by the effect, and the rigidity in the longitudinal direction of the vehicle body and the torsional rigidity can be improved. Therefore, a vibration and noise suppression function for reducing vibrations and noise in the passenger compartment S, and a load path that protects the interior of the passenger compartment S by dispersing and transmitting the collision load applied from the front toward the rear of the vehicle body at the time of a front collision. The function is secured. Moreover, it is also possible to expand the wiring freedom degree of harnesses, such as a vehicle-mounted electrical component, by utilizing the open cross-section part C3 of the open top surface. Furthermore, the collision load in the vehicle width direction that has acted on the center pillar 7 can be directly distributed to the tunnel portion 2 and the like via the floor cross member 12.

Next, a seat bracket mounting structure for mounting the seat device will be described.
In this vehicle V, a driver seat device and a passenger seat device are provided adjacent to each other on the front side of the passenger compartment S, and a rear seat device is provided on the rear side of the passenger compartment S (whichever (Not shown).
As shown in FIGS. 1 and 2, the driver seat device and the passenger seat device include a front inner seat bracket (hereinafter referred to as a first bracket) 31 and a front outer seat bracket (hereinafter referred to as a second bracket). 32, a rear inner seat bracket (hereinafter referred to as a third bracket) 33, and a rear outer seat bracket (hereinafter referred to as a fourth bracket) 34, respectively, are attached to the vehicle body side. Since the seat brackets of the driver seat device and the passenger seat device have the same configuration, the following description will be made in common.

  By installing the first bracket 31 and the second bracket 32 at the front position of the floor cross member 12 and the third bracket 33 and the fourth bracket 34 at the rear position of the floor cross member 12, the first and third brackets 31, 33 is configured to support the seat slider mechanism (not shown) on the inner side in the vehicle width direction, and to support the seat slider mechanism on the outer side in the vehicle width direction with the second and fourth brackets 32 and 34. As shown in FIG. 1, the second and fourth brackets 32 and 34 are joined to the upper surface of the floor panel 1 and the vertical wall portion 4 a of the side sill 4 by welding.

As shown in FIGS. 4, 8, 9, and 10, the first bracket 31 is formed in a substantially rectangular parallelepiped shape, and includes a vertical wall portion 2 a of the tunnel portion 2, an inner portion in the vehicle width direction of the floor panel 1, and a connecting member. 26 is connected to the middle portion of the main body 26. The first bracket 31 includes an outer wall portion 31a, a front wall portion 31b, a rear wall portion 31c, and an upper wall portion 31d that partially covers the upper portion of the open section C3.
An opening 31k is formed in the center portion of the outer wall portion 31a, and an outer flange portion 31e that extends outward from the lower end in the vehicle width direction and is joined to the floor panel 1 is provided.

The front wall portion 31b is provided with a front flange portion 31f (connecting member flange portion) that extends forward from the lower end and is joined to the upper surface of the connecting member 26, and extends forward from the inner end portion in the vehicle width direction to the tunnel portion. 1st inner flange part 31g joined to 2 is provided.
The rear wall portion 31c is provided with a rear flange portion 31h (connecting member flange portion) that extends rearward from the lower end and is joined to the upper surface of the connecting member 26, and extends rearward from the inner end portion in the vehicle width direction to the tunnel. A second inner flange portion 31 i joined to the portion 2 is provided.
The upper wall portion 31d is provided with a third inner flange portion 31j that extends upward from the inner end portion in the vehicle width direction and is joined to the tunnel portion 2.

As shown in FIGS. 6, 8, 11, and 12, the third bracket 33 is formed in a substantially rectangular parallelepiped shape and is connected to the vertical wall portion 2 a of the tunnel portion 2 and the inner portion in the vehicle width direction of the floor panel 1. Has been. The third bracket 33 includes an outer wall portion 33a, a front wall portion 33b, a rear wall portion 33c, and an upper wall portion 33d that partially covers the upper portion of the open section C3.
The outer wall 33a has an opening 33k formed at the center, and an outer flange 33e that extends outward from the lower end in the vehicle width direction and is joined to the floor panel 1.

The front wall portion 33b is provided with a front leg portion 33l extending downward from the lower end and a first inner flange portion 33g extending forward from the inner end portion in the vehicle width direction and joined to the tunnel portion 2.
A front flange 33f that extends forward and is joined to the bottom 22c of the intermediate tunnel side member 22 is provided at the lower end of the front leg 33l.
The rear wall portion 33c is provided with a rear leg portion 33m extending downward from the lower end and a second inner flange portion 33i extending rearward from the vehicle width direction inner end portion and joined to the tunnel portion 2.
A rear flange portion 33h that extends rearward and is joined to the bottom portion 22c of the intermediate tunnel side member 22 is provided at the lower end of the rear leg portion 33m.
The upper wall portion 33d is provided with a third inner flange portion 31j that extends upward from the inner end portion in the vehicle width direction and is joined to the tunnel portion 2.

  As described above, the upper portion of the open cross-section C3 is partially connected in the vehicle width direction by the first and third brackets 31 and 33, so that the vehicle body rigidity in the vehicle width direction can be strengthened. The fall of the width direction can be prevented. And since the 1st bracket 31 is supported by the connection member 26, a leg part becomes unnecessary and can attain size reduction of components.

Next, operations and effects of the lower body structure of the vehicle according to the first embodiment will be described.
According to the lower body structure of this vehicle, the vibration side noise suppression function and the load path function can be secured by the tunnel side member 3 having an open cross-sectional shape, so that the vibration and noise in the passenger compartment S can be reduced. The room space can be protected. Further, since the tunnel side member 3 forms the open section C3 having an open top surface, the material steel plate corresponding to the top surface of the tunnel side member 3 can be reduced, and the projecting portions 21d, 22d, and 23d of the tunnel side member 3 can be reduced. Is joined to the inner end of the floor panel 1 in the vehicle width direction, so that assembly work can be performed without changing the conventional work process.

  The front tunnel side member 21 of the tunnel side members 3 is formed so that a downward projecting amount decreases toward the front of the vehicle body, and cooperates with a front reinforcing member 24 provided on the bottom 21c of the front tunnel side member 21. The closed section C1 is formed by working. By forming the closed cross-section C1 using the bottom 21c of the front tunnel side member 21, it is possible to receive an impact load by the front tunnel side member 21 at the time of the front collision, and the collision into the passenger compartment S can be prevented. The impact can be reduced.

Since the bead portion 21e extending in the longitudinal direction of the vehicle body is formed on the bottom portion 21c of the front tunnel side member 21, the longitudinal strength of the front tunnel side member 21 can be increased, and the collision into the passenger compartment S can be further increased. The impact can be reduced.
A kick-up portion K that is continuous with the rear end of the floor panel 1 is provided, and the rear tunnel side member 23 of the tunnel side members 3 is formed so that the downward projecting amount decreases toward the rear of the vehicle body. The closed cross-section C2 is formed in cooperation with the rear reinforcing member 25 provided on the bottom 23c of the rim, and the closed cross-section C2 is formed to extend to the vicinity of the kick-up portion K. Thereby, the impact load applied to the front tunnel side member 21 at the time of the front collision is dispersed while being transmitted to the rear part of the vehicle body via the rear tunnel side member 23, and the influence of the collision into the passenger compartment S can be reduced. it can. Moreover, at the time of a rear collision, the impact load can be received by the rear tunnel side member 23, and the influence of the collision into the passenger compartment S can be reduced.

A first (third) bracket 31 (33) for attaching the seat device to the tunnel side member 3 is provided, and the first (third) bracket 31 (33) is at least the inner end in the vehicle width direction of the floor panel 1. And flange portions 31e, 31g, 31i, 31j (33e, 33g, 33i, 33j) for joining to the vertical wall portion 2a of the tunnel portion 2, respectively.
As a result , the vehicle body rigidity in the vehicle width direction can be increased using the first (third) bracket 31 (33), and the side wall can be prevented from collapsing in the vehicle width direction during a side collision. .

  Since the connecting member 26 for connecting the inner end in the vehicle width direction of the floor panel 1 and the vertical wall portion 2a of the tunnel portion 2 is provided and the flange portions 31f and 31h of the first bracket 31 are joined to the connecting member 26, The first bracket 31 can be installed using the connecting member 26 for preventing the tunnel portion 2 from falling in the vehicle width direction.

Next, a modification in which the above embodiment is partially changed will be described.
1] The example in which the tunnel side member has an open cross-section having a substantially U-shaped cross section having two ridge lines has been described. However, it is sufficient that at least the tunnel side member has an open cross-section extending in the front-rear direction. A tunnel side member that does not include Even a tunnel side member having three or more ridge lines can basically exhibit the same effect.

2] In the above embodiment, the example in which the front inner seat bracket is supported by the connecting member that connects the tunnel portion and the floor panel has been described, but the connecting member may be omitted. Further, the rear inner seat bracket may be supported by the connecting member, and both inner seat brackets may be supported by the connecting member.

3) In addition, those skilled in the art can implement the present invention by adding various modifications to the embodiments without departing from the spirit of the present invention, and the present invention includes such modifications. is there.

  The present invention reduces the weight of a vehicle body by changing the shape of a tunnel side member in a lower vehicle body structure of a vehicle having a tunnel portion that protrudes upward from a vehicle width direction center portion of a floor panel and extends in the vehicle body longitudinal direction. .

DESCRIPTION OF SYMBOLS 1 Floor panel 2 Tunnel part 3 Tunnel side member 8 Dash panel 21 Front tunnel side member 21c Bottom part 21e Bead part 23 Rear tunnel side member 23c Bottom part 24 Front side reinforcement member 25 Rear side reinforcement member 26 Connection member 31 1st bracket 31e, 31g , Flange portions 31i, 31j
33 Third bracket 33e, 33g, flange 33i, 33j
V Vehicle E Engine room S Car compartment C1, C2 Closed section C3 Open section

Claims (6)

Lower vehicle body structure of a vehicle comprising a floor panel extending rearward from the lower end of a dash panel that partitions the engine room and the vehicle compartment, and a tunnel portion protruding upward from a vehicle width direction center portion of the floor panel and extending rearward of the vehicle body In
A tunnel side member that extends in the vehicle body front-rear direction and projects downward from the floor panel to form an open cross-section with an open top surface is provided on the vehicle width direction outer side portion of the tunnel portion ,
Of the tunnel side members, the end side tunnel side member is formed such that the downward projecting amount decreases toward the end side, and is provided on the end side provided on the bottom side of the end side tunnel side member. A lower body structure of a vehicle, wherein a closed cross section is formed in cooperation with a reinforcing member . The end side tunnel side member has a front tunnel side member formed so that the amount of protrusion downward in the forward direction of the vehicle body is reduced,
The lower body structure of a vehicle according to claim 1, wherein the end side reinforcing member has a front side reinforcing member .   The lower body structure of a vehicle according to claim 2, wherein a bead portion extending in a longitudinal direction of the vehicle body is formed at a bottom portion of the front tunnel side member. Provide a kick-up part connected to the rear end of the floor panel,
The end side tunnel side member has a rear tunnel side member formed so that the amount of protrusion downward toward the rear of the vehicle body is reduced,
The end side reinforcing member has a rear reinforcing member,
The closed cross section formed in cooperation with the rear side reinforcing member is formed so as to extend to the vicinity of the kick-up portion. Lower body structure of the vehicle. Lower vehicle body structure of a vehicle comprising a floor panel extending rearward from the lower end of a dash panel that partitions the engine room and the vehicle compartment, and a tunnel portion protruding upward from a vehicle width direction center portion of the floor panel and extending rearward of the vehicle body In
A tunnel side member extending in the longitudinal direction of the vehicle body is provided on the vehicle width direction outer side portion of the tunnel portion,
The tunnel side member is formed such that an outer end portion in the vehicle width direction is joined to an inner end portion in the vehicle width direction of the floor panel and protrudes downward from the floor panel to form an open cross section with an open top surface.
A seat bracket for attaching a seat device to the tunnel side member is provided,
The seat bracket, at least the lower vehicle body structure of the vehicles you further comprising a flange portion for each joined to the vehicle width direction inside end portion and the vertical wall portion of the tunnel portion of the floor panel. Providing a connecting member for connecting the inner end of the floor panel in the vehicle width direction and the vertical wall portion of the tunnel portion;
The vehicle lower body structure according to claim 5, wherein a flange portion for a connecting member of the seat bracket is joined to the connecting member.