JP2008230421A - Lower body structure of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lower body structure of a vehicle capable of enhancing collision safety for a vehicle body. <P>SOLUTION: This lower body structure comprises a pair of left and right front wheel suspension tower sections 14, a pair of left and right front side frames 2 extended in the vehicle longitudinal direction, to which the lower sections of these front wheel suspension tower sections are connected, a pair of left and right side sills 12 connected to the rear sections of these front side frames respectively and extended in the vehicle longitudinal direction at both edges of a vehicle compartment floor, a pair of left and right rear side frames 16 connected to these side sills at their front sections and extended in the vehicle longitudinal direction in the inner sides of rear wheel wheel houses at their rear sections, a cross member 34 extended in the vehicle width direction and mutually combining the rear side frames, and inclined cross members 40 connecting at least any one of the rear end sections of the front side frames and connecting sections between the rear side frames and the cross member on the opposite side about left and right to the front side frames. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lower body structure of a vehicle, and more particularly to a lower body structure of a vehicle having a front side frame and a side sill.

  Conventionally, the frame structure in the lower part of the vehicle is a cross beam composed of side members and side sills extending in the vehicle front-rear direction and a plurality of cross members extending in the vehicle width direction in order to maintain the rigidity, strength or collision safety of the vehicle body. It is common to have a structure. On the other hand, Patent Document 1 discloses a structure in which a rear portion of a front side frame is divided into two portions and coupled to a side sill and a floor tunnel.

JP 2001-219873 A

  In recent years, there has been a demand for further improving the collision safety of vehicles. For this purpose, various measures are conceivable, but the present inventors have focused on the fact that the frame structure basically contributes greatly to the rigidity and strength of the vehicle. That is, it was thought that collision safety could be greatly increased if the rigidity and strength were dramatically improved by the innovative frame structure. In other words, it is considered that the conventional frame structure as described above has a limit to greatly improve the collision safety.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a vehicle lower body structure that can increase the rigidity and strength of the vehicle body.

In order to achieve the above object, according to the present invention, a pair of left and right front wheel suspension towers, a pair of left and right front side frames extending in the vehicle front-rear direction are coupled to the lower portions of the front wheel suspension towers, and the front sides thereof. A pair of left and right side sills connected to the rear part of the frame and extending in the vehicle longitudinal direction at both edges of the passenger compartment floor, the front part is connected to these side sills, and the rear part is inside the rear wheel house in the vehicle longitudinal direction A pair of left and right rear side frames extending in the direction of the vehicle, a cross member extending in the vehicle width direction so as to connect the pair of left and right rear side frames to each other, a rear end portion of at least one of the pair of left and right front side frames, and the front side frame The rear side frame on the opposite side to the left and the connecting part of the cross member It is characterized by having a line cross member.
In the present invention configured as described above, since the skew cross member is provided in addition to the front side frame, the side sill, the rear side frame, and the cross member, the rigidity and strength of the vehicle body can be increased. In particular, the torsional rigidity of the vehicle body can be increased by the oblique cross member. Here, the torsional rigidity is a torsion when, for example, the suspension tower portion of the front wheel and the rear end portion of the rear side frame are respectively determined as load input points. When such a torsion is received, the axial force that can be received by the oblique cross member is increased, and the torsional rigidity of the vehicle body, particularly the torsional rigidity of the rear portion of the passenger compartment floor can be improved. Furthermore, according to the present invention, since the triangular cross member, the cross member, and the side sill form a triangular member, it is possible to efficiently disperse the impact load applied during the offset collision. The input load received by the front side frame can be transmitted to the side sill immediately behind the front side frame, and can also be transmitted to the other side sill by the skew cross member. As described above, in the conventional girder structure, the load can be distributed to the left and right side sills which do not contribute much to the load sharing at the time of an offset collision.

In the present invention, preferably, the diagonal cross members are provided in a pair of left and right, and the cross members are X-shaped members that intersect with each other at the center in the vehicle width direction and are coupled to each other.
In the present invention configured as described above, the oblique cross members are X-shaped members that intersect with each other at the center in the vehicle width direction and are coupled to each other. The bending deformation of the left and right oblique cross members themselves that are received can be suppressed and the load can be distributed more reliably. Further, since the oblique cross member extends obliquely, the axial force that can be received by each member of the oblique cross member with respect to the load input to the vehicle body increases, and the torsional rigidity of the vehicle body, particularly the front part of the passenger compartment floor. Torsional rigidity can be improved.

In the present invention, it is preferable that the vehicle further includes a floor tunnel that extends in the vehicle longitudinal direction and bulges upward at an intermediate portion in the vehicle width direction, and the pair of left and right oblique cross members are provided on the lower surface portion of the passenger compartment floor. The portion where the pair of left and right oblique cross members are joined to each other is composed of a cross member formed in an X-shape that is separate from the other portions. It extends across the bottom of the floor tunnel and each end thereof is coupled to the other part.
In the present invention configured as described above, the portion where the pair of left and right oblique cross members intersect with each other is configured by a cross member separate from the other portions. It can be attached later than other members. Therefore, before installing the cross member, it is possible to easily arrange the exhaust pipe, the propeller shaft, and the like in the floor tunnel. Further, the X-shaped member can be extended linearly without climbing the floor tunnel.

Further, in the present invention, preferably, the rear side frame is formed at a narrower distance in the rear side portion that overlaps the rear wheel wheel house in a side view than the front end portion thereof, and the cross member is a rear wheel wheel. This is a first rear cross member that overlaps the house in a side view and extends in the vehicle width direction at portions that are formed at a narrow interval, and connects the rear side frames to each other.
In the present invention configured as described above, the cross member is a first rear portion that overlaps the rear wheel wheel house in a side view and extends in the vehicle width direction at a portion formed at a narrow interval with each other to connect the rear side frames to each other. Since it is a cross member, the torsional rigidity of the vehicle body can be effectively increased.

In the present invention, it is preferable that the first rear cross member further includes a second rear cross member that joins the front end portions of the pair of left and right rear side frames and / or the pair of left and right side sills to the front side of the first rear cross member. The row cross member partially overlaps with the second rear cross member in plan view, and the oblique cross member and the second rear cross member are coupled to each other at the overlap portion.
In the present invention configured as described above, the skew cross member is coupled at the overlapping portion with the second rear cross member extending in the vehicle width direction in which both ends are coupled to the rear side frame and / or the side sill. Even when a force such as bending or twisting is applied to the slanting cross member, the second rear cross member works so as to stretch and support in the vehicle width direction, thereby suppressing the deformation of the slanting cross member. I can do it.

In the present invention, preferably, the cross member extending in the vehicle width direction is a cross member that couples the front end portions of the pair of left and right rear side frames to each other.
In the present invention configured as described above, the cross member is a cross member that couples the front end portions of the pair of left and right rear side frames to each other, so that the torsional rigidity of the vehicle body can be effectively increased.

In the present invention, it is preferable that the front cross member further extends in the vehicle width direction on the front side of the vehicle front-rear direction intermediate portion of the side sill and is coupled to the upper surface of the passenger compartment floor, and the oblique cross member. Is coupled to the lower surface portion of the passenger compartment floor, and the skew cross member partially overlaps with the front cross member in plan view, and is joined to each other with the passenger compartment floor sandwiched between the overlapping portions.
In the present invention configured as described above, since the skew cross member is coupled to the front cross member extending in the vehicle width direction, a force such as bending or twisting is applied to the skew cross member. However, since the front cross member works so as to support the cross member in the vehicle width direction, deformation of the skew cross member can be suppressed.

  According to the present invention, the rigidity and strength of the vehicle body can be increased.

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, a first embodiment of the present invention will be described. FIG. 1 is a bottom view of a lower vehicle body structure of a vehicle according to a first embodiment of the present invention as viewed from below, and FIG. 2 is a diagonal view of the lower vehicle body structure of a vehicle according to the first embodiment of the present invention. It is a perspective view.
First, the configuration of the frame extending in the longitudinal direction of the vehicle body and the configuration of the floor will be mainly described.
As shown in FIGS. 1 and 2, the vehicle 1 has a pair of left and right front side frames 2 that extend in the longitudinal direction of the vehicle body at the side of the engine room in front of the vehicle 1. The front side frame 2 has a closed cross-sectional structure with a square cross section. A portion on the rear side of the front side frame 2 extends obliquely downward toward the rear below the dash panel 4 and curves inward in the vehicle width direction. The front side frame 2 is connected to the lower surface portion of the floor panel (first floor panel) 6 in a portion behind the curved portion that extends in the horizontal direction and in the longitudinal direction of the vehicle body. The floor panel 6 is formed with a floor tunnel 8 extending in the longitudinal direction of the vehicle body and bulging upward at the center in the vehicle width direction. The rear end portion of the floor tunnel 8 is connected to a kick-up portion (kick-up panel) 18 that rises obliquely upward from the floor panel 6.

A torque box 10 is coupled to a rear end portion of each front side frame 2 at an outer portion in the vehicle width direction. These torque boxes 10 are coupled to the side sill 12 at the outer ends in the vehicle width direction. These torque boxes 10 have a predetermined closed cross section, extend obliquely rearward, and are formed so as to effectively transmit a load applied to the front side frame 2 to the side sill 12. In this way, the rear end portion of the front side frame 2 is coupled to the side sill 12. The side sill 12 has a predetermined closed cross-sectional structure, and extends in the longitudinal direction of the vehicle body at both edges of the vehicle in the vehicle width direction. A floor panel 6 is coupled to the inner walls of these side sills 12.
Here, as shown in FIG. 2, the front side frames 2 are respectively formed with suspension towers 14 for supporting a front strut suspension (not shown) on the upper part thereof, and these suspension towers 14 are respectively apron rain. It is coupled to the force 15. Since the suspension tower 14 is coupled to the front side frame 2, the load input from the suspension is transmitted to the other frame members 12 and the like via the suspension tower 14 and the front side frame 2.

  Next, rear side frames 16 are coupled to the inner side of the rear end of the side sill 12, respectively. These rear side frames 16 have a hat-like shape (not shown) that opens upward, and flange portions (not shown) formed on the left and right sides of the upper portion thereof are provided with the kick-up portion 18 and the second portion. The frame is formed as a closed cross-section frame that is coupled to and integrated with each lower surface portion of the floor panel 20. Although not shown, a rear suspension (not shown) is attached to the rear side frame 16, and load input from these rear suspensions is transmitted to other frame members 12 and the like via the rear side frame 16. Is done.

Next, in addition to the above-described frame extending mainly in the vehicle longitudinal direction, the vehicle 1 is formed with several cross members extending in the vehicle width direction. These frame members will be described.
First, at the front end of each front side frame 2, No. 2 extending in the vehicle width direction. One cross member 22 is coupled. This No. The 1 cross member 22 is attached to the front side frame 2 via a crush can (not shown) or the like, and has a bumper reinforcement function.
Next, no. Two cross members 24 are formed. This No. The two cross members have a hat-like cross-sectional shape that opens downward (see FIG. 7), and flange portions formed on the left and right sides of the lower portion are joined to and integrated with the upper surface of the floor panel 6. It is formed as a frame with a closed cross section. This No. The two cross members 24 are joined to the side sill 12 at both ends, and mainly increase the rigidity in the vehicle width direction and also serve as seat brackets that support the leg portions of the front seat. This No. The two cross members 24 extend along a mountain-like cross-sectional shape of the floor tunnel 8 in a front view.

  This No. A so-called seat bracket 26 is formed behind the two cross members 24. As shown in FIG. 2, these seat brackets 26 are coupled to a coupling portion of a B pillar (center pillar) 28 and a side sill 12 provided at an intermediate portion in the vehicle longitudinal direction (see FIG. 4). The seat bracket 26 extends inward in the vehicle width direction from these connecting portions, and terminates between the side sill 12 and the floor tunnel 8 on the floor panel 6. The seat bracket 26 has a hat-like cross-sectional shape opened downward (see FIG. 4), and flange portions formed on both left and right sides of the lower portion of the seat bracket 26 are coupled to and integrated with the upper surface portion of the floor panel 6. It is formed as a frame with a closed cross section. The seat bracket 26 also serves as a seat bracket that supports the leg portion of the front seat.

  Behind these seat brackets 26 are No. Three cross members 32 are formed. This No. The three cross members 32 have a hat-like shape (not shown) that opens upward, and flange portions (not shown) formed on both the left and right sides of the upper portion match the inclination of the kick-up portion 18. The flange portion is formed as a frame having a closed cross section which is connected to the lower surface portion of the kick-up portion 18 and is integrated. This No. Both ends of the 3 cross member 32 are coupled to the side sill 12 and the rear side frame 16 so as to mainly increase the rigidity in the vehicle width direction. More specifically, no. No. 3 cross member 32 has both ends. The rear side portions of both end portions of the three cross member 32 are coupled to the front end portion of the rear side frame 16.

This No. No. 3 behind the cross member 32 A four cross member 34 is formed. This No. The four cross member 34 has a hat-like cross-sectional shape (not shown) that opens upward, and flanges (not shown) formed on both the left and right sides of the upper portion are formed by the kick-up portion 18 and the second floor. It is formed as a frame with a closed cross section that is coupled to and integrated with the lower surface of the panel 20. This No. Both ends of the 4 cross member 34 are coupled to the rear side frame 16 so as to increase mainly the rigidity in the vehicle width direction.
This No. Behind the 4 cross member 34 is a No. 4 cross member. A five cross member 36 is formed. Here, the second floor panel 20 constitutes a part of the floor surface of the trunk space, and a spare tire pan 35 is formed. No. The 5 cross member 32 is coupled to the lower surface of the second floor panel 20 and is bent downward so as to support the spare tire pan 35.

Here, the side sill 12, the rear side frame 16, 3 cross member 32 and No. 3 The frame configuration of the four cross member 34 will be described.
First, the rear side frame 16 has an outer side surface portion in the vehicle width direction of a front end portion thereof coupled to an inner side surface portion of the side sill 12. Further, the front end portion of the rear side frame 16 is No. The three cross members 32 are coupled to the rear surface portion. No. Both ends of the 3 cross member 32 are coupled to the inner side portion of the rear end of the side sill 12. Thus, no. The three cross members 32 connect the left and right side sills 12 to each other and also connect the left and right rear side frames 16 to each other. The rear side frame 16 includes the side sill 12 and the No. 3 frame. The three cross members 32 extend rearward and inward in the vehicle width direction so as to avoid the rear wheel wheel house 37, and are formed along the rear wheel wheel house 37. The portion where the rear side frame 16 overlaps with the wheel house 37 in a side view is the mutual rear side frame 16 rather than the front end portion (the connecting portion between the rear side frame 16 and the side sill 12 and the No. 3 cross member 32). The width in the vehicle width direction is narrow. No. mentioned above. The 4 cross member 34 is provided in a portion where the rear side frame 16 and the wheel house 37 overlap in this side view. The cross member 32 is shorter than the cross member 32.

Next, referring to FIG. 1 and FIG. 2, a configuration relating to the arrangement of the skew cross member according to the first embodiment of the present invention will be described. In addition to the above-described members extending in the vehicle longitudinal direction and the vehicle width direction, the skew cross member is a frame member extending obliquely with respect to both the vehicle body longitudinal direction and the vehicle width direction in plan view. Hereinafter, these members will be described.
First, a skew cross member (front skew cross member) 40 is coupled to the rear end portion of the front side frame 2 at an inner portion in the vehicle width direction. The oblique cross member 40 is composed of two cross members that intersect in an X shape as an overall shape. And one of them is the opposite side, that is, the right side of the vehicle width direction No. The four cross members 34 and the connecting portion 30 of the rear side frame 16 are extended. Similarly, the other side of the oblique cross member 40 is connected to the rear side inner portion 2a of the front side frame 2 on the right side in the vehicle width direction on the opposite side, i.e. The four cross members 34 and the connecting portion 30 of the rear side frame 16 are extended.
As described above, each of the oblique cross members 40 has a No. on the rear end portion of the front side frame 2 and the opposite side in the vehicle width direction. The 4 cross member 34 and the coupling part 30 of the rear side frame 16 are coupled. As described above, the oblique cross members 40 are formed of X-shaped members that intersect with each other, and each extend so as to cross the space below the floor tunnel 8.

Next, a specific structure of the oblique cross member will be described with reference to FIGS.
FIG. 3 is a perspective view of the floor panel according to the first embodiment of the present invention and the linear member of the first oblique cross member attached to the floor panel, as viewed obliquely from below. FIG. FIG. 5 is a perspective view of an X-shaped member of an intersecting portion of the first skew cross member according to the first embodiment as viewed obliquely from below, and FIG. 5 is a perspective view of the first skew cross member according to the first embodiment of the present invention. FIG. 6 is a perspective view of the structure of the connecting portion between the linear member and the X-shaped member as viewed obliquely from below. FIG. 6 is a perspective view of the linear member of the first oblique cross member according to the first embodiment of the present invention; It is sectional drawing which shows the cross-section of the coupling | bond part with a character-shaped member, and is the figure upside down was shown.
The skew cross member 40 is composed of a plurality of members. First, as shown in FIG. 3, the oblique cross member 40 includes two linear members 42 extending from the rear end inner portion 2 a of the front side frame 2, 4 cross members 34 and two straight members 44 extending from the coupling portion 30 of the rear side frame 16. Each of these linear members 42 and 44 has a hat-like cross-sectional shape opened upward (see FIGS. 4 and 7), and flange portions 42 c and 44 c formed on the left and right sides of the upper portion thereof are the floor panel 6. The frame is configured as a closed cross-section frame that is coupled to and integrated with the lower surface portion of the frame.

  Further, the slanting cross member 40 is a middle part of the member 42, and the No. The two cross members 24 are also coupled (see FIG. 7). The skew cross member 40 is an intermediate portion of the member 44, and the No. 3 is coupled to the lower surface of the cross member 32 (see FIGS. 1 and 2).

  As shown in FIG. 3, the four linear members 42 and 44 extend to the vicinity of the bulging portion of the floor tunnel 8. A member for connecting the four linear members 42 and 44 to each other and constituting the oblique cross member 40 extending in an X shape as a whole is an X-shaped cross member 46 shown in FIG. This cross member 46 has a hat-like cross section that opens upward, and a flange portion 46a is formed at the edge thereof. The cross member 46 can be formed by hot pressing. However, in the error portion as shown by A in FIG. 4, the flange portion is not provided due to the restriction of the press work.

As shown in FIGS. 4 and 5, the cross member 46 is provided with holes 46 b through which the bolts pass at the four ends thereof. On the other hand, holes 42b and 44b for passing bolts are also provided at the ends of the four linear members 42 and 44, respectively. As shown in FIG. 6, a weld nut 48 is provided inside the holes of the four linear members 42 and 44.
In addition, enlarged portions 46 c are provided at the four end portions of the cross member 46, respectively. And the notch 46d is formed with such an enlarged part 46c. The inner side dimensions of these enlarged portions 46c are configured to be substantially the same as the outer side dimensions of the ends of the four linear members 42 and 44, and four inward sides of the enlarged portion 46c. The ends of the straight members 42 and 44 are fitted into each other. At that time, the notch 46 d of the enlarged portion 46 c engages with the end portions of the linear members 42 and 44.

When assembling, first, the linear members 42 and 44 are installed as shown in FIG. 3, and then the cross member 46 shown in FIG. 4 is aligned as shown in FIG. Then, the bolt 49 is screwed into the weld nut 48 from the outer side of the enlarged portion 46c, thereby forming the oblique cross member 40 that crosses and extends in an X shape as a whole.
With such an assembling method, first, for example, after the catalyst 7 and the exhaust pipe 9 shown in FIG. 3 are installed, the X-shaped oblique cross member 40 can be configured. As described above, the exhaust pipe, the propeller shaft, and the like in the floor tunnel can be easily arranged. Further, the X-shaped cross member can be extended linearly without being bent so as to climb the floor tunnel.

Next, mainly referring to FIG. 7, the skew cross member 40, the floor panel 6, A connection structure with the two cross member 24 will be described. FIG. 7 shows a skew cross member, a floor panel, and No. 1 according to the first embodiment of the present invention. It is the perspective view which looked at the composition of combination with two cross members from the slanting lower side.
As described above, no. The two cross members 24 are configured to form a closed cross section at the upper surface portion of the floor panel 6. On the other hand, the oblique cross member 40 is configured to form a closed cross section at the lower surface portion of the floor panel 6. Then, as shown in FIG. A portion where the flange portion of the two cross member 24 and the flange portion of the oblique cross member 40 overlap is joined to each other by welding with the floor panel 6 interposed therebetween.

Next, the function and effect of the first embodiment of the present invention will be described.
According to the first embodiment of the present invention, since the skew cross member is provided in addition to the front side frame, the side sill, the rear side frame, and the cross member, the rigidity and strength of the vehicle body can be increased. In particular, it works effectively against torsion of the vehicle body. That is, the torsional rigidity of the vehicle body can be increased by the skew cross member 40. Here, the torsional rigidity means, for example, the torsion when the suspension tower portion 14 of the front wheel and the rear side frame 16 (for example, the rear end portion of the rear side frame 16) to which the rear suspension is attached are respectively defined as load input points. It is. When such torsion is received, the axial force that can be received by the members 42 and 44 of the oblique cross member is increased, and the torsional rigidity of the vehicle body, in particular, the torsional rigidity of the rear part of the passenger compartment floor can be improved. .
Furthermore, according to the first embodiment of the present invention, the skew cross member 40, No. 4 is used. Since the substantially cross-shaped member is comprised by the 4 cross member 34, the side sill 12, the rear side frame 16, etc., the impact load added at the time of an offset collision can be disperse | distributed efficiently.

  And according to 1st Embodiment of this invention, the front side frame 2 and the side sill 12 are connected by the torque box 10 which has a predetermined | prescribed closed cross section. Further, the skew cross member 40 allows the rear end 2a of the pair of left and right front side frames 2 to be The 4 cross member 34 and the coupling part 30 of the rear side frame 16 are connected. Such an oblique cross member 40 connects the front side frame 2 and the rear side frame 16 on the opposite side to the front side frame 2. According to such a configuration, the input load received by the front side frame 2 at the time of an offset collision is transmitted to one side sill 12 (the side sill 12 closer to the front side frame 2) via the torque box 10. Can be transmitted to the other rear side frame 16 (the rear side frame 16 on the side far from the front side frame 2) by the skew cross member 40. In this way, the input load received by the front side frame 2 can be transmitted to the side sill 12 immediately behind the front side frame 2 and also transmitted to the other rear side frame 16 by the skew cross member 40. As described above, in the conventional cross beam structure, the load can be distributed to the rear side frame 16 that does not contribute much to the load sharing at the time of an offset collision.

  According to the first embodiment of the present invention, since the oblique cross member 40 is the X-shaped members 42 and 44, the members 42 and 44 extending obliquely can be received with respect to the torsion of the entire vehicle body. The axial force increases, and the torsional rigidity of the vehicle body, particularly the torsional rigidity of the floor panel 6 can be improved. Furthermore, the bending deformation of the cross members 42 and 44 themselves generated by receiving the load at the time of a frontal collision can be suppressed to distribute the load more reliably.

Furthermore, according to the first embodiment of the present invention, the oblique cross member 40 is a No. The four cross members 34 and the coupling portion 30 of the rear side frame 16 are coupled. Therefore, even when a force such as bending or twisting is applied to the vehicle body, the skew cross member 40 works to be supported in a stretched state in the axial direction. Further, the rear side frame 16 and Since the four cross member 34 can receive the load, deformation of the skew cross member 40 itself is also suppressed.
Furthermore, according to the first embodiment of the present invention, the skew cross member 40 has a No. Three cross members 32 are coupled. This No. Both ends of the 3 cross member 32 are coupled to the rear side frame 16 and the side sill 12. Therefore, even when a force such as bending or twisting is applied to the oblique cross member 40, the No. 4 The three cross members 32 work so as to be stretched and supported in the vehicle width direction. Thereby, deformation of the skew cross member 40 itself is also suppressed.

  Further, according to the first embodiment of the present invention, No. 1 is used. The two cross members 24 are configured to have a closed cross section at the upper surface portion of the floor panel 6, and the first oblique cross member 40 is configured to have a closed cross section at the lower surface portion of the floor panel 6. And No. The two cross members 24 and the first oblique cross member 40 are coupled to each other with the floor panel 6 interposed therebetween. Thus, no. The two cross members 24 and the first oblique cross member 40 partially overlap in plan view, and are connected to each other with the floor panel 6 sandwiched between the overlap portions. The bending deformation of 42 and 44 itself can be suppressed.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 8 is a bottom view of the lower vehicle body structure of the vehicle according to the second embodiment of the present invention as viewed from below, and FIG. 9 is a diagonal view of the lower vehicle body structure of the vehicle according to the second embodiment of the present invention. It is a perspective view.
This second embodiment is different from the lower structure of the first embodiment in that the front side frame 2, the side sill 12, the rear side frame 16, the cross members 22, 24, 26, 32, 34, 36, and the floor panel 6 And the floor tunnel 8 have the same configuration. On the other hand, the configuration of the skew cross member is different. Here, a description of the same configuration as that of the first embodiment is omitted, and a configuration different from that of the first embodiment will be mainly described.
As shown in FIGS. 8 and 9, the skew cross member 140 according to the second embodiment is composed of two cross members that intersect in an X shape, as in the first embodiment. And the one end part of the skew cross member 140 is each couple | bonded with the rear-end part of the front side frame 2 similarly to 1st Embodiment. On the other hand, the other end portion of the skew cross member 140 is different from the first embodiment in that, in the vehicle width direction opposite side to the front side frame 2 to which the one end portion is coupled, The three cross members 32 are coupled to a coupling portion 130 between the side sill 12 and the rear side frame 16.
Also in the second embodiment configured as described above, the torsional rigidity of the vehicle body can be increased by the skew cross member 140 as described above. Further, the oblique cross member 40, No. Since the three cross members 32 and the side sill 12 form a substantially triangular member, it is possible to efficiently disperse the impact load applied during the offset collision.

  Also in the second embodiment, as in the above-described embodiment, the input load received by the front side frame 2 is transmitted to the side sill 12 immediately behind the front side frame 2, and the skew cross member 140 also transmits the input load. The other side sill 12 and the rear side frame 16 can also be transmitted. As described above, in the conventional cross beam structure, the load can be distributed to the other side sill 12 and the rear side frame 16 that do not contribute much to the load sharing at the time of an offset collision.

Furthermore, according to the second embodiment, the skew cross member 140 is No. The three cross members 32 are coupled to the coupling portion 130. Therefore, even when a force such as bending or twisting is applied to the vehicle body, the skew cross member 140 works to stretch and support in the axial direction and receives the load. Furthermore, since the side sill 12 and the rear side frame 16 receive the load, deformation of the skew cross member 40 itself can be suppressed.
Furthermore, according to the embodiment of the present invention, the skew cross member 140 has a No. 2 coupled to the cross member 24. Accordingly, even when a force such as bending or twisting is applied to the vehicle body, the oblique cross member 40 is supported by stretching in the axial direction. 2 The cross member 24 works so as to stretch and support in the vehicle width direction. And No. The deformation of the skew cross member 140 itself is also suppressed by the two cross members 24.

It is the bottom view which looked at the lower body structure of the vehicle by a 1st embodiment of the present invention from the lower part. It is the perspective view which looked at the lower vehicle body structure of the vehicle by 1st Embodiment of this invention from diagonally downward. It is the perspective view which looked at the linear member of the floor panel by 1st Embodiment of this invention, and the 1st diagonal cross member attached to this floor panel from the diagonally lower side. It is the perspective view which looked at the X-shaped member of the crossing part of the 1st skew cross member by 1st Embodiment of this invention from the diagonally downward side. It is the perspective view which looked at the structure of the connection part of the linear member of the 1st skew cross member by 1st Embodiment of this invention, and an X-shaped member from the diagonally downward side. It is sectional drawing which shows the cross-section of the coupling | bond part of the linear member of the 1st skew cross member by 1st Embodiment of this invention, and an X-shaped member, and is the figure shown upside down. The skew cross member, floor panel, and No. 1 according to the first embodiment of the present invention. It is the perspective view which looked at the composition of combination with two cross members from the slanting lower side. It is the bottom view which looked at the lower vehicle body structure of the vehicle by 2nd Embodiment of this invention from the downward direction. It is the perspective view which looked at the lower vehicle body structure of the vehicle by 2nd Embodiment of this invention from diagonally downward.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Front side frame 6 Floor panel 8 Floor tunnel 10 Torque box 12 Side sill 14 Suspension tower 16 Rear side frame 24 2 Cross member 26 Seat bracket 28 B pillar 30 4 Cross member 34 and rear side frame 16 coupling portion 32 3 cross member 34 4 cross member 34a 4 Cross member vehicle width direction intermediate portion 36 Wheel house 40 Skew cross members 42 and 44 according to the first embodiment Straight member 46 of the skew cross member according to the first embodiment Cross member of the skew cross member according to the first embodiment 130 No. Joint part 140 of 3 cross members and side sills and rear side frames Skew cross members 142, 144 according to the second embodiment Straight members of the skew cross members according to the second embodiment

Claims (7)

A pair of left and right front wheel suspension towers;
A pair of left and right front side frames extending in the vehicle front-rear direction are coupled to the lower portions of these front wheel suspension towers,
A pair of left and right side sills connected to the rear portions of these front side frames and extending in the vehicle front-rear direction at both edges of the passenger compartment floor;
A pair of left and right rear side frames whose front part is connected to these side sills and whose rear part extends in the vehicle longitudinal direction inside the rear wheel wheel house,
A cross member extending in the vehicle width direction so as to connect the pair of left and right rear side frames to each other;
A skew cross member that connects a rear end portion of at least one of the pair of left and right front side frames and a connecting portion of the rear side frame and the cross member on the opposite side to the front side frame; A lower body structure of a vehicle characterized by comprising:   2. The lower body of a vehicle according to claim 1, wherein the skew cross members are provided in a pair of left and right, and the cross members are X-shaped members that intersect with each other at the center in the vehicle width direction and are coupled to each other. Construction. Furthermore, it has a floor tunnel that extends in the vehicle longitudinal direction at the middle in the vehicle width direction and bulges upward,
The pair of left and right oblique cross members are coupled to the lower surface of the passenger compartment floor,
A portion where the pair of left and right oblique cross members intersect with each other is configured by a cross member formed in an X-shape separate from the other portions, and the cross member is a side view of the floor tunnel. The lower body structure of a vehicle according to claim 2, wherein the lower body structure of the vehicle extends across the lower side and each end thereof is coupled to the other part. The rear side frame is formed at a narrower distance than the front end portion of the rear side wheel house and the rear side portion overlapping in the side view,
The cross member extending in the vehicle width direction is a first rear cross member that extends in the vehicle width direction at a portion that overlaps the rear wheel wheel house in a side view and is formed at a narrow interval, and connects the rear side frames to each other. The lower body structure of a vehicle according to any one of claims 1 to 3. Furthermore, it has a second rear cross member that couples the front end portions of the pair of left and right rear side frames and / or the pair of left and right side sills to the front side of the first rear cross member,
5. The skew cross member partially overlaps with the second rear cross member in plan view, and the skew cross member and the second rear cross member are coupled to each other at the overlap portion. The lower body structure of the vehicle described in 1.   The lower body structure of a vehicle according to any one of claims 1 to 3, wherein the cross member extending in the vehicle width direction is a cross member that couples front end portions of the pair of left and right rear side frames to each other. Furthermore, it has a front cross member that extends in the vehicle width direction on the front side of the vehicle sill longitudinal middle portion of the side sill and is coupled to the vehicle compartment floor upper surface.
The skew cross member is coupled to the lower surface of the passenger compartment floor,
The vehicle according to any one of claims 1 to 6, wherein the skew cross member partially overlaps with the front cross member in a plan view, and is coupled to each other with the overlapped portion sandwiching the passenger compartment floor. Lower body structure.

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