JP6079713B2 - 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 support structure portion that is disposed within a closed cross section formed by a rear side frame and supports a suspension cross member via a suspension bolt.

  Conventionally, in a lower vehicle body structure of a vehicle, a pair of left and right rear side frames each having a closed cross section extending in the front-rear direction in cooperation with the floor panel are formed on the lower surface side of the floor panel, and the pair of rear side frames are arranged in the vehicle width. A cross member that is connected in the direction is provided, and a rear suspension mechanism is provided below the pair of left and right rear side frames. A suspension cross member, which is a skeleton member of the rear suspension mechanism, is supported via a suspension mounting bolt (so-called suspension bolt) on a support structure portion disposed within a closed cross section in which a rear side frame is configured in cooperation with a floor panel. Has been.

  The lower body structure of a vehicle disclosed in Patent Document 1 includes a U-shaped stiffening member that extends in the front-rear direction by connecting an upper surface portion of a side sill and a bottom wall portion of a rear side frame, and a closed cross section formed by the stiffening member. And a bracket for supporting the suspension member, and a bottom plate portion to which the nut pipe is fixed, and the left and right side walls of the stiffening member extending upward from the left and right ends of the bottom plate portion. There are provided a pair of left and right flange portions joined to the respective portions, and a pair of front and rear flange portions joined to the bottom wall portion of the stiffening member and extending downward from both front and rear end portions of the bottom plate portion.

JP 2005-53431 A

The lower vehicle body structure of the vehicle of Patent Document 1 suppresses bending of the rear side frame by a stiffening member for reinforcing the rigidity of the rear side frame, and further, a bracket (support structure portion) that supports the suspension member on the stiffening member. ) Is maintained, the attachment rigidity of the suspension member is increased.
However, the lower vehicle body structure of the vehicle disclosed in Patent Document 1 requires a large stiffening member extending rearward from the middle portion of the kick-up portion of the rear side frame, which may increase production costs and vehicle body weight.

When the vehicle is traveling, the brackets arranged in the closed cross section of the rear side frame are subject to vertical vibration caused by traveling from the rear suspension mechanism via suspension bolts. Input load is concentrated.
Due to the input load accompanying this traveling vibration, the cross section of the closed side surface formed by the rear side frame may be broken, and as a result, the vehicle body rigidity may be lowered.

  An object of the present invention is to provide a lower vehicle body structure of a vehicle that can improve vehicle body rigidity without increasing the vehicle body weight.

  The lower vehicle body structure of the vehicle according to claim 1 includes a pair of left and right rear side frames each having a closed cross section extending in the longitudinal direction of the vehicle body in cooperation with the floor panel on the lower surface side of the floor panel, and the pair of rear side frames. In the lower vehicle body structure of a vehicle, comprising: a cross member connected in the vehicle width direction; and a pair of left and right support structures disposed within the pair of closed cross sections and supporting suspension cross members via suspension bolts. The pair of support structure portions includes a substantially hat-shaped upper bracket whose longitudinal section perpendicular to the vehicle width direction is opened upward, and a lower bracket having a top plate portion joined from below to the bottom plate portion of the upper bracket. Each of the upper brackets is characterized in that the front leg portion and the rear leg portion are formed so as to extend along the extension surface of the front wall portion and the extension surface of the rear wall portion of the cross member, respectively.

According to the lower vehicle body structure of the vehicle, the support structure has a substantially hat-shaped upper bracket whose longitudinal section perpendicular to the vehicle width direction opens upward, and a top plate portion joined from below to the bottom plate portion of the upper bracket. Therefore, the upper bracket can be disposed in the closed cross section formed by the rear side frame and the floor panel using the lower bracket without newly providing a large stiffening member.
In addition, since the front leg portion and the rear leg portion of the upper bracket are formed so as to follow the extension surface of the front wall portion and the extension surface of the rear wall portion of the cross member, respectively, the input input from the suspension cross member via the suspension bolt The load can be distributed and transmitted to the front wall portion and the rear wall portion of the cross member via the front leg portion and the rear leg portion of the upper bracket, and the cross-sectional collapse of the closed cross section formed by the rear side frame and the floor panel can be suppressed. .

According to a second aspect of the present invention, in the first aspect of the invention, a pair of upper flange portions extending upward from both ends in the vehicle width direction of the bottom plate portion of the upper bracket and a vehicle width direction of the top plate portion of the lower bracket. A pair of lower flange portions extending upward from both ends, and the pair of upper flange portions and the pair of lower flange portions are respectively overlapped and joined to the left and right side wall portions of the rear side frame, respectively. It is characterized by that.
According to this, the support rigidity of the upper bracket can be increased, and the collapse of the cross section of the closed cross section constituted by the rear side frame and the floor panel can be further suppressed.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a pair of left and right rear wheel houses disposed on the left and right ends of the floor panel, and an inner portion in the vehicle width direction of the pair of rear wheel houses. And a pair of left and right reinforcing frames respectively disposed in the vicinity of the inside thereof, wherein the lower half portion disposed in the vicinity of the inside is a pair of flange portions at a position corresponding to the cross member. A pair of left and right reinforcing frames joined to the panel, wherein at least one of the pair of flange portions provided at the upper ends of the front leg and rear leg of the upper bracket is a pair of flanges of the reinforcing frame It is characterized in that it is joined to the floor panel at substantially the same position in the vehicle longitudinal direction as at least one of the parts.
According to this configuration, the input load input from the suspension cross member via the suspension bolt can be distributed and transmitted via the reinforcing frame via the two paths of the rear wheel house and the cross member. It is possible to further suppress the collapse of the configured closed cross section.

  According to the present invention, by providing the support structure portion with a load dispersion transmission function, the vehicle body rigidity can be improved without increasing the vehicle body weight.

It is the perspective view which looked at the rear part body structure of the vehicle concerning Example 1 of the present invention from the cabin side. It is a top view. It is the perspective view which looked at the rear part body structure from the slanting lower part. It is a principal part perspective view of FIG. It is a principal part perspective view of FIG. It is a disassembled perspective view of a support structure part. 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 the IX-IX sectional view taken on the line of FIG.

  Hereinafter, modes for carrying out the present invention will be described based on examples. In the present embodiment, the direction of arrow F will be described as the front, and the direction of arrow L as the left.

Embodiment 1 of the present invention will be described below with reference to FIGS.
As shown in FIGS. 1 to 5, a vehicle V according to this embodiment includes a floor panel 1, a pair of left and right rear side frames 2, and a cross member 3 that couples the pair of rear side frames 2 in the vehicle width direction. And a pair of left and right support structures 4 for supporting a pair of left and right rear suspension mechanisms (not shown) disposed below the floor panel 1.

First, the floor panel 1 will be described.
The floor panel 1 is provided across the pair of left and right rear side frames 2 in the vehicle width direction and extends in the front-rear direction, and forms a floor surface of the vehicle V.
The floor panel 1 accommodates a kick-up portion K that is inclined in the rearward and upward direction and is formed in the middle in the front-rear direction, a rear floor for forming a luggage compartment behind the kick-up portion K, and a spare tire. Spare tire pans and the like are provided.
The kick-up portion K supports a pair of left and right rear seats (not shown) on which a rear passenger can be seated.

A pair of left and right rear wheel houses 5 are disposed on the left and right ends of the floor panel 1.
As shown in FIGS. 1, 2, 7, and 8, the pair of left and right rear wheel houses 5 includes a wheel house outer 5a that bulges outward from the lower end of the side panel inner 6b in the vehicle width direction, and a side panel inner. The wheel house inner 5b bulges inward in the vehicle width direction from the lower end of 6b. Since each pair of left and right members has a symmetrical structure, the structure of the right member will be mainly described below.

The wheel house outer 5a is formed in a partial annular shape, and an upper edge portion is connected to an arc-shaped lower end portion of the side panel inner 6b, and a lower edge portion is connected to a lower end portion of the side panel outer 6a. The wheel house inner 5b is formed in a partial bowl shape, and a suspension housing 7 that bulges toward the passenger compartment is formed in the upper half of the wheel house inner 5b.
The suspension housing 7 is formed in a substantially L shape when viewed from the front, and forms a columnar space in which the damper device 8 of the rear suspension can be accommodated. The suspension housing 7 is provided at a substantially central portion in the front-rear direction including the top of the wheel house inner 5b, and is formed by a support portion 7a capable of supporting the upper end portion of the damper device 8 and a vertical wall portion 7b.
The top of the suspension housing 7 is connected to the side panel inner 6 b by a reinforcing member 9 and is connected to the floor panel 1 by a reinforcing frame 10.

As shown in FIGS. 1, 2, 8, and 9, the reinforcing frame 10 is formed in a substantially L shape when viewed from the front, and has a top wall portion 10a having a substantially horizontal cross section and a bottom wall portion 10a. The front wall portion 10b extending upward from the front end portion and the rear wall portion 10c extending upward from the rear end portion of the bottom wall portion 10a are provided, and the vertical cross section perpendicular to the vehicle width direction is downward by the respective wall portions 10a to 10c. A substantially hat shape is formed.
The lower end portion of the reinforcing frame 10 cooperates with the floor panel 1 by joining both flange portions 10d and 10e formed at the upper end portions of the front wall portion 10b and the rear wall portion 10c to the upper surface of the floor panel 1, respectively. Thus, a closed section C3 extending in the vehicle width direction is formed on the upper surface side of the floor panel 1.

Next, the pair of left and right rear side frames 2 will be described.
As shown in FIGS. 3 to 5 and FIGS. 7 to 9, the rear side frame 2 is formed so as to extend rearward along the kick-up portion K and extend in the front-rear direction in the middle part of the front side. The rear side frame 2 includes a bottom wall portion 2a having a substantially horizontal longitudinal section perpendicular to the front-rear direction, an outer wall portion 2b extending upward from an outer end in the vehicle width direction of the bottom wall portion 2a, and a vehicle having a bottom wall portion 2a. An inner wall 2c extending upward from the inner end in the width direction, and each wall 2a to 2c forms a substantially U-shape in which a vertical cross section perpendicular to the front-rear direction is opened upward.

The rear side frame 2 has a closed cross section extending in the longitudinal direction of the vehicle in cooperation with the floor panel 1 by joining both flange portions formed at the upper end portions of the outer wall portion 2b and the inner wall portion 2c to the lower surface of the floor panel 1 respectively. C1 is configured on the lower surface side of the floor panel 1.
In the closed cross section C1, a support structure portion 4 is disposed at a portion corresponding to the top portion of the kick-up portion K.

Next, the cross member 3 will be described.
As shown in FIGS. 3, 5, and 8, the cross member 3 connects a portion corresponding to the top of the kick-up portion K in the vehicle width direction between the pair of left and right rear side frames 2.
The cross member 3 includes a bottom wall portion 3a having a substantially horizontal cross section perpendicular to the vehicle width direction, a front wall portion 3b extending in a forward upward inclined manner from a front end portion of the bottom wall portion 3a, and a bottom wall portion 3a. The rear wall 3c extends rearward and upward from the rear end, and each wall 3a to 3c forms a substantially hat shape in which a vertical section perpendicular to the vehicle width direction opens upward.

The cross member 3 cooperates with the floor panel 1 by joining both flange portions 3d and 3e formed on the upper end portions of the front wall portion 3b and the rear wall portion 3c to the lower surface of the floor panel 1, respectively. A closed section C2 extending in the direction is formed on the lower surface side of the floor panel 1.
As shown in FIGS. 1, 2, and 8, the floor panel 1 is formed with a convex portion 1 a that protrudes upward corresponding to the cross member 3 in order to increase the section modulus of the closed section C <b> 2.
As shown in FIG. 3, the left and right end portions of the cross member 3 are formed as a pair of left and right rear side frames by joining flange portions formed extending from the respective wall portions 3a to 3c to inner wall portions 2c on both left and right sides. 2 is connected.

Next, the pair of left and right support structure portions 4 will be described.
The support structure 4 includes an upper bracket 11 that supports a suspension cross member 15 of a rear suspension mechanism via a suspension mounting bolt (hereinafter abbreviated as a suspension bolt) B, and a lower bracket that supports the upper bracket 11 from below. 12.

  As shown in FIGS. 6 and 9, the upper bracket 11 includes a substantially horizontal rectangular bottom plate portion 11a, a front leg portion 11b extending upward from the front end portion of the bottom plate portion 11a, and a front side from the upper end portion of the front leg portion 11b. A flange portion 11e extending upward, a rear leg portion 11c extending upward from the rear end portion of the bottom plate portion 11a, and a flange portion 11f extending rearward from the upper end portion of the rear leg portion 11c, thereby being orthogonal to the vehicle width direction. The vertical cross-section is configured to have a substantially hat shape opened upward.

  The bottom plate portion 11a includes a hole portion 11s through which the suspension bolt B can be inserted in the center portion, a bolt seat portion 11t that protrudes upward at the outer peripheral portion of the hole portion 11s and can support the head portion of the suspension bolt B from below, and a bottom plate And a pair of left and right upper flange portions 11d extending upward from both ends in the vehicle width direction of the portion 11a.

As shown in FIG. 5, the front leg portion 11 b extends from the front end portion of the bottom plate portion 11 a in a forward upward inclined manner along the extended surface of the front wall portion 3 b of the cross member 3.
The flange portion provided at the inner end portion in the vehicle width direction of the front leg portion 11b is joined to the flange portion provided at the outer end portion in the vehicle width direction of the front wall portion 3b via the inner wall portion 2c.
The flange portion 11 e is joined to the lower surface of the floor panel 1 at a position ahead of the flange portion 10 d of the reinforcing frame 10.

The rear leg portion 11c extends from the rear end portion of the bottom plate portion 11a in an upwardly inclined manner along the extended surface of the rear wall portion 3c of the cross member 3.
The flange portion provided at the inner end portion in the vehicle width direction of the rear leg portion 11c is joined to the flange portion provided at the outer end portion in the vehicle width direction of the rear wall portion 3c via the inner wall portion 2c.
As shown in FIG. 9, the flange portion 11f is triple-bonded by welding with the flange portion 10e of the reinforcing frame 10 and the floor panel 1 interposed therebetween.

  As shown in FIGS. 6 and 9, the lower bracket 12 includes a substantially horizontal rectangular top plate portion 12a, a front leg portion 12b extending downward from the front end portion of the top plate portion 12a, and a lower end portion of the front leg portion 12b. A flange portion 12e extending forward, a rear leg portion 12c extending downward from the rear end portion of the top plate portion 12a, and a flange portion 12f extending rearward from the lower end portion of the rear leg portion 12c are provided. The perpendicular | vertical longitudinal cross-section comprises the substantially hat shape opened below.

The top plate portion 12a includes a hole portion 12s through which the suspension bolt B can be inserted in a central portion, and a pair of left and right lower flange portions 12d extending upward from both ends of the top plate portion 12a in the vehicle width direction, and the bottom surface of the bottom plate portion 11a. It is joined to.
The front leg portion 12b extends from the front end portion of the top plate portion 12a in a downwardly inclined manner, and the flange portion 12e is triple-bonded by welding with the joint flange of the bracket 16 and the bottom wall portion 2a of the rear side frame 2 interposed therebetween. . The rear leg portion 12c extends rearward and downwardly from the rear end portion of the top plate portion 12a, and the flange portion 12f is triple-joined by welding with the joint flange of the bracket 16 and the bottom wall portion 2a of the rear side frame 2 interposed therebetween. ing.

  As shown in FIGS. 4 and 8, the pair of left and right lower flange portions 12 d are joined to the rear side frame 2 in a state where they overlap each other on the outer side in the vehicle width direction of the pair of left and right upper flange portions 11 d. That is, the outer wall portion 2b, the lower flange portion 12d, and the upper flange portion 11d are triple welded on the outer side in the vehicle width direction, and the inner wall portion 2c, the lower flange portion 12d, and the upper flange portion 11d are three on the inner side in the vehicle width direction. Heavy welded.

Next, functions and effects of the rear body structure of the vehicle according to the embodiment will be described.
According to the rear vehicle body structure of the vehicle, the support structure 4 is joined from below to the substantially hat-shaped upper bracket 11 whose longitudinal section perpendicular to the vehicle width direction opens upward, and the bottom plate portion 11a of the upper bracket 11. Since the lower bracket 12 having the top plate portion 12a is provided, the upper bracket 11 is configured by the rear side frame 2 and the floor panel 1 using the lower bracket 12 without newly providing a large stiffening member. It can be arranged in the closed section C1. Further, since the front leg portion 11b and the rear leg portion 11c of the upper bracket 11 are formed so as to be along the extension surface of the front wall portion 3b and the extension surface of the rear wall portion 3c of the cross member 3, respectively, The input load input via B can be distributed and transmitted to the front wall portion 3b and the rear wall portion 3c of the cross member 3 via the front leg portion 11b and the rear leg portion 11c of the upper bracket 11, and the rear side frame 2 The collapse of the cross section of the closed cross section C1 configured by the floor panel 1 can be suppressed.

  A pair of upper flange portions 11d extending upward from both ends in the vehicle width direction of the bottom plate portion 11a of the upper bracket 11 and a pair of lower portions extending upward from both ends in the vehicle width direction of the top plate portion 12a of the lower bracket 12 respectively. A side flange portion 12d is provided, and a pair of upper flange portions 11 and a pair of lower flange portions 12 are overlapped and joined to the left and right side wall portions of the rear side frame 2, respectively. According to this, the support rigidity of the upper bracket 11 can be increased, and the collapse of the cross section of the closed cross section C1 formed by the rear side frame 2 and the floor panel 1 can be further suppressed.

  A pair of left and right rear wheel houses 5 disposed on both left and right ends of the floor panel 1, and a pair of left and right reinforcing frames respectively disposed on the inner side in the vehicle width direction of the pair of rear wheel houses 5 and in the vicinity thereof. 10 and a pair of left and right reinforcing frames 10 joined to the floor panel 1 at a position corresponding to the cross member 3 by a pair of flange portions 10d and 10e. At least one of the pair of flange portions 11e and 11f provided at the upper ends of the front leg portion 11b and the rear leg portion 11c of the upper bracket 11 is at least one of the pair of flange portions 10d and 10e of the reinforcing frame 10. Are joined to the floor panel 1 at substantially the same position in the longitudinal direction of the vehicle body. According to this configuration, the input load input from the suspension cross member 15 via the suspension bolt B can be distributed and transmitted via the reinforcement frame 10 through the two paths of the rear wheel house 5 and the cross member 3. The cross-sectional collapse of the closed cross section C1 configured by the frame 2 and the floor panel 1 can be further suppressed.

Next, a modification in which the above embodiment is partially changed will be described.
1) In the above-described embodiment, the example in which the front leg portion and the rear leg portion of the upper bracket are along the extended surfaces of the front wall portion and the rear wall portion of the cross member has been described. The extension surface of the front wall and the rear wall of the cross member may be along the extension surface, and the front leg and the rear leg of the lower bracket may be set to extend along the extension surface of the front and rear wall portions of the cross member. good.

2] In the above-described embodiment, the example in which the flange portion of the rear leg portion of the upper bracket is triple-bonded with the rear flange portion of the reinforcing frame and the floor panel interposed therebetween has been described. The rear flange portion may be welded with the front flange portion of the reinforcing frame and the floor panel interposed therebetween. Further, it is possible to triple-join the front leg portion and the rear leg flange portion of the upper bracket with the front flange portion and the rear flange portion of the reinforcing frame.

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.

DESCRIPTION OF SYMBOLS 1 Floor panel 2 Rear side frame 2b Outer wall part 2c Inner wall part 3 Cross member 3b Front wall part 3c Rear wall part 4 Support structure part 5 Rear wheel house 10 Reinforcement frames 10d and 10e (Reinforcement frame) Flange part 11 Upper bracket 11a Bottom plate part 11d Upper flange portion 11e, 11f (Upper bracket) Flange portion 12 Lower bracket 12a Top plate portion 12d Lower flange portion 15 Suspension cross member V Vehicle B Suspension bolt C1 Closed section

Claims (3)

A pair of left and right rear side frames each having a closed cross section extending in the longitudinal direction of the vehicle body in cooperation with the floor panel on the lower surface side of the floor panel; a cross member connecting the pair of rear side frames in the vehicle width direction; In a lower vehicle body structure of a vehicle provided with a pair of left and right support structures disposed within a pair of closed cross sections and supporting suspension cross members via suspension bolts,
The pair of support structure portions includes a substantially hat-shaped upper bracket whose longitudinal section perpendicular to the vehicle width direction is opened upward, and a lower bracket having a top plate portion joined to the bottom plate portion of the upper bracket from below. With each
A lower vehicle body structure for a vehicle, wherein a front leg portion and a rear leg portion of the upper bracket are formed to extend along an extension surface of a front wall portion and an extension surface of a rear wall portion of the cross member, respectively. A pair of upper flange portions respectively extending upward from both ends in the vehicle width direction of the bottom plate portion of the upper bracket;
A pair of lower flange portions respectively extending upward from both ends in the vehicle width direction of the top plate portion of the lower bracket,
2. The lower body structure of a vehicle according to claim 1, wherein the pair of upper flange portions and the pair of lower flange portions are respectively overlapped and joined to the left and right side wall portions of the rear side frame. A pair of left and right rear wheel houses disposed on the left and right ends of the floor panel;
A pair of left and right reinforcing frames disposed on the inner side in the vehicle width direction of the pair of rear wheel houses and the inner vicinity thereof, and the lower half part disposed on the inner vicinity is a pair. A pair of left and right reinforcing frames joined to the floor panel at a position corresponding to the cross member by a flange portion;
At least one flange portion of the pair of flange portions provided at the upper ends of the front leg portion and the rear leg portion of the upper bracket is substantially at the same position in the vehicle longitudinal direction as at least one of the pair of flange portions of the reinforcing frame. The lower body structure of a vehicle according to claim 1 or 2, wherein the lower body structure is joined to a floor panel.