JP2008230418A - 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 rigidity and strength of a vehicle body. <P>SOLUTION: This lower body structure comprises a pair of left and right front side frames 2, a pair of left and right side sills 12 connected to the rear sections of the front side frames respectively and extended in the vehicle longitudinal direction at both edges of a vehicle compartment floor, center pillars 28 connecting the intermediate sections of the side sills 12 in the vehicle longitudinal direction and the roof of the vehicle, a pair of left and right rear side frames 16, a cross member 32 extended in the vehicle width direction and mutually connecting the rear side frames and/or the side sills, front part inclined cross members 40 connecting at least any one of the rear ends of the front side frames and the connecting section between the center pillars and the side sills on the opposite side about left and right to the front side frames, and rear part inclined cross members 50 connecting the connecting sections between the center pillars and the side sills and the intermediate section of the cross member in the vehicle width direction. <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, a side sill, a center pillar, and a rear side frame.

  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 lower body structure of the vehicle according to the present invention, a pair of left and right front side frames extending in the vehicle front-rear direction, and both edges of the passenger compartment floor connected to the rear portions of these front side frames, respectively. A pair of left and right side sills extending in the vehicle front-rear direction, a pair of left and right center pillars extending in the vehicle vertical direction so as to connect the vehicle middle in the vehicle front-rear direction and the roof of the vehicle, and a pair of left and right sides extending in the vehicle front-rear direction. A rear side frame, a front end portion of the pair of left and right rear side frames and / or a cross member extending in the vehicle width direction so as to connect the pair of left and right side sills, and a rear end portion of at least one of the pair of left and right front side frames; The center pillar and side sill on the opposite side of the front side frame The front oblique cross member extending obliquely in plan view so as to connect the connecting portion, at least one of the connecting portion of the center pillar and the side sill, and the intermediate portion of the cross member in the vehicle width direction are connected And a rear oblique cross member extending obliquely in plan view.
In the present invention configured as described above, in addition to the front side frame, the side sill, the rear side frame, and the cross member, since the front oblique cross member and the rear oblique cross member that extend obliquely in plan view, In addition, the strength can be increased. In particular, since rigidity and strength can be increased with respect to a side collision, this will be described. Here, first, the deformation of the vehicle body at the time of a side collision by the conventional vehicle body structure will be described. In the conventional vehicle body structure, at the time of a side collision, the center pillar falls inward, and as a result, the side sill is twisted by the center pillar. Then, it becomes clear that the vehicle compartment floor near the center pillar is deformed so that it is turned up, and then the vehicle body is deformed so that the side sill is deformed so as to be bent inward and bites into the vehicle interior. Yes. Conventionally, at the time of such a side collision, only a short cross member provided on the passenger compartment floor connecting the side sill and the floor tunnel can receive the load at the time of the side collision. On the other hand, in the present invention, since both the front oblique cross member and the rear oblique cross member are coupled to the connecting portion of the center pillar and the side sill, the twist of the center pillar and the side sill is suppressed. The collision load at the time of a side collision can be distributed to the front oblique cross member, the rear oblique cross member, and the side sill. The load distributed to the front skew cross member and the rear skew cross member is further distributed to the front side frame, the cross member, and the like. In this way, the load can be effectively received by a large number of strength members. Furthermore, the presence of the front oblique cross member and the rear oblique cross member extending obliquely on the passenger compartment floor can prevent the passenger compartment floor from being turned up and the side sill from being folded. In this way, the rigidity and strength of the vehicle are increased.

In order to achieve the above object, according to the lower body structure of the vehicle according to the present invention, a pair of left and right front side frames extending in the vehicle front-rear direction, and both edges of the passenger compartment floor connected to the rear portions of these front side frames, respectively. A pair of left and right side sills extending in the vehicle front-rear direction, a pair of left and right center pillars extending in the vehicle vertical direction so as to connect the vehicle sill in the vehicle front-rear direction and the roof of the vehicle, and the rear wheel rather than the front end. The width of the vehicle is so that the pair of left and right rear side frames extending in the vehicle front-rear direction and the narrow side portions of the rear side frames are connected to each other, with the rear side portion overlapping the house and side view being formed at a narrower interval. Cross member extending in the direction, the rear end of at least one of the pair of left and right front side frames, and its A front oblique cross member extending obliquely in plan view so as to connect the center pillar and the side sill connecting portion on the opposite side to the front side frame, and at least one of the center pillar and side sill connecting portion; And a rear oblique cross member extending obliquely in plan view so as to connect the intermediate member of the cross member in the vehicle width direction.
In the present invention configured as described above, in addition to the front side frame, the side sill, the rear side frame, and the cross member, since the front oblique cross member and the rear oblique cross member that extend obliquely in plan view, In addition, the strength can be increased. In particular, since rigidity and strength can be increased with respect to a side collision, this will be described. Here, first, the deformation of the vehicle body at the time of a side collision by the conventional vehicle body structure will be described. In the conventional vehicle body structure, at the time of a side collision, the center pillar falls inward, and as a result, the side sill is twisted by the center pillar. Then, it becomes clear that the vehicle compartment floor near the center pillar is deformed so that it is turned up, and then the vehicle body is deformed so that the side sill is deformed so as to be bent inward and bites into the vehicle interior. Yes. Conventionally, at the time of such a side collision, only a short cross member provided on the passenger compartment floor connecting the side sill and the floor tunnel can receive the load at the time of the side collision. On the other hand, in the present invention, since both the front oblique cross member and the rear oblique cross member are coupled to the connecting portion of the center pillar and the side sill, the twist of the center pillar and the side sill is suppressed. The collision load at the time of a side collision can be distributed to the front oblique cross member, the rear oblique cross member, and the side sill. The load distributed to the front skew cross member and the rear skew cross member is further distributed to the front side frame, the cross member, and the like. In this way, the load can be effectively received by a large number of strength members. Furthermore, the presence of the front oblique cross member and the rear oblique cross member extending obliquely on the passenger compartment floor can prevent the passenger compartment floor from being turned up and the side sill from being folded. In this way, the rigidity and strength of the vehicle are increased.

Further, in the present invention, preferably, the front oblique cross members are provided in a pair of left and right, and these 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 front 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. It is possible to more reliably disperse the load by suppressing the bending deformation of the left and right front oblique cross members themselves caused by the load. Further, since the front oblique cross member extends obliquely, the axial force that can be received by each cross member with respect to the load input to the vehicle body increases, and the torsional rigidity of the vehicle body, particularly the torsion of the front part of the passenger compartment floor. Stiffness 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 in the vehicle width direction intermediate portion, and the pair of left and right front oblique cross members are provided on the lower surface of the vehicle compartment floor. The part where the pair of left and right front oblique cross members intersect with each other is composed of a cross member formed in an X shape separate from the other parts. And extending across the lower side of the floor tunnel in a side view and each end thereof being coupled to the other part.
In the present invention configured as described above, the portion where the pair of left and right front oblique cross members intersect each other is formed by a cross member separate from the other portions. The member can be attached later than the 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.

In the present invention, preferably, the rear oblique cross members are provided in a pair of left and right, both of which are connected to the intermediate portion in the vehicle width direction of the cross member and the other ends are the center pillar and the side sill, respectively. The V-shaped member is joined to the connecting portion.
In the present invention configured as described above, since the rear oblique cross member is a cross member extending obliquely in a V shape, the axial force that can be received by each cross member is increased, the torsional rigidity of the vehicle body, In particular, the torsional rigidity at the rear of the passenger compartment floor can be improved. Furthermore, conventionally, the load was transmitted to the cross member via other members such as a side sill, but according to the present invention, the load can be directly transmitted to the cross member. This load can be effectively received by the cross member.

  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 the lower body structure according to the first embodiment of the vehicle of the present invention as viewed from below, and FIG. 2 is a view of the lower body structure according to the first embodiment of the vehicle of the present invention as viewed obliquely from below. 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 (see FIG. 3), and extends in the longitudinal direction of the vehicle body at the edges on both sides in the vehicle width direction of the vehicle. Moreover, the floor panel 6 is couple | bonded with the inner wall part of these side sills 12 (refer FIG. 3).
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. 9), and flange portions formed on the left and right sides of the lower portion are joined to and integrated with the upper surface portion 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 B pillar (center pillar) 28 and a coupling portion 30 of the side sill 12 provided at an intermediate portion in the longitudinal direction of the vehicle body (see FIG. 4). The seat bracket 26 extends inward in the vehicle width direction from these coupling portions 30, 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. 3 and both ends of the cross member 32 are coupled to the inner side portion of the rear end of the side sill 12. 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, the structure of the B pillar 28, the side sill 12, and the cross member connecting portion 30 will be described with reference to FIGS. FIG. 3 is a perspective view illustrating a configuration of a coupling portion of the side sill, the B pillar, and the cross member according to the first embodiment of the present invention, and FIG. 4 is a side sill as viewed along line IV-IV in FIG. It is sectional drawing which shows the cross-section of the connection part of a pillar and a cross member.
As shown in FIGS. 3 and 4, the side sill 12 includes a side sill inner 12a, a side sill reinforcement 12b, and a side sill outer 12c. The B pillar 28 includes a pillar inner 28a, a pillar inner negative set 28b, a pillar reinforcement 28c, and a pillar outer 28d formed continuously with the above-described side sill outer 12c.
At the lower end of the side sill 12, a pillar inner 28a extending vertically downward through the side sill 12 is sandwiched between the side sill inner 12a, the side sill reinforcement 12b, and the side sill outer 12c, and these members are welded to each other. At the upper end of the side sill 12, the pillar inner 28a is sandwiched between the side sill inner 12a and the side sill reinforcement 12b, and these members are welded together with the pillar inner gusset 28b provided on the inner side in the vehicle width direction. Has been. Further, a pillar reinforcement 28c extends in the vertical direction of the vehicle body inside the B pillar 28, and a lower end portion thereof is welded to the side sill reinforcement 12b.

Further, the floor panel 6, the above-described seat bracket 26, and first and second oblique cross members 40 and 50 described later are coupled to the coupling portion 30 configured as described above.
As shown in FIGS. 3 and 4, the floor panel 6 has a flange portion 6 a at the end edge portion, and the flange portion 6 a is welded to the inner side surface of the side sill 12.
Further, the seat bracket 26 is provided with a notch 26 a at an end edge portion thereof, and the notch 26 a is formed so as to be aligned with the shoulder portion of the side sill 12. According to the notch 26a configured as described above, a side thrust is effectively applied to the seat bracket 26 from the side sill 12 and the B pillar 28 at the time of a side collision.
Further, a first oblique cross member 40 (to be described later) is also provided with a notch 44a, and this notch 44a is formed so as to be aligned with the lower shoulder portion of the side sill 12. Although not shown, the second oblique cross member 50 is similarly configured. Further, at the time of a side collision, a side thrust is effectively applied to the first and second oblique cross members 40 and 50 from the side sill 12 and the B pillar 28.

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 first skew cross member (front skew cross member) 40 is coupled to a rear end portion of the front side frame 2 at an inner portion in the vehicle width direction. The first oblique cross member 40 is composed of two cross members that intersect in an X shape as an overall shape. One of them extends from the rear end inner portion 2a of the front side frame 2 on the left side in the vehicle width direction to the opposite side, that is, the connecting portion 30 of the B pillar 28 and the side sill 12 on the right side in the vehicle width direction. Similarly, the other side of the first oblique cross member 40 is connected to the B pillar 28 and the side sill 12 on the opposite side, that is, the left side in the vehicle width direction, from the rear end inner part 2a of the front side frame 2 on the right side in the vehicle width direction. It extends to the part 30. As described above, each of the first oblique cross members 40 connects the rear end portion of the front side frame 2 and the connecting portion 30 of the B pillar 28 and the side sill 12 on the opposite side in the vehicle width direction. As described above, the first oblique cross member 40 is formed of X-shaped members intersecting each other, and extends so as to cross the space below the floor tunnel 8.

  Further, a second oblique cross member (rear oblique cross member) 50 is coupled to the coupling portion 30 of the B pillar 28 and the side sill 12. The second oblique cross member 50 is composed of two cross members having a V shape as an overall shape. And one of them is No. from the B pillar 28 on the left side in the vehicle width direction and the connecting portion 30 of the side sill 12. The four cross members 34 extend to an intermediate portion 34a in the vehicle width direction. Similarly, the other side of the second oblique cross member 50 is connected to the right side of the B pillar 28 on the right side in the vehicle width direction and the connecting portion 30 of the side sill 12 with No. 2 The four cross members 34 extend to an intermediate portion 34a in the vehicle width direction. As described above, the second oblique cross member 50 includes the B pillar 28 and the connecting portion 30 of the side sill 12, and The middle part 34a of the four cross member 34 is coupled.

Next, a specific structure of the first oblique cross member will be described with reference to FIGS. 1, 2, 5 to 8.
FIG. 5 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, and FIG. FIG. 7 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. 7 shows the first skew cross member according to the first embodiment of the present invention. FIG. 8 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. 8 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 first oblique cross member 40 is composed of a plurality of members. First, as shown in FIG. 3, the first oblique cross member 40 includes two linear members 42 extending from the rear end inner portion 2 a of the front side frame 2, and a connecting portion 30 of the B pillar 28 and the side sill 12. And two linear members 44 extending. Each of these linear members 42 and 44 has a hat-like cross-sectional shape opened upward (see FIGS. 4 and 9), and flange portions 42 c and 44 c formed on the left and right sides of the upper portion thereof are provided on 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.
As shown in FIG. 4, the two linear members 44 are provided with the notches 44 a as described above, and the notches 44 a are formed so as to be aligned with the shoulders below the side sill 12. . The two linear members 42 existing on the other front side are also coupled to the front side frame 2 in the same manner.

  As shown in FIG. 5, 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 first 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 indicated by A in FIG. 6, the flange portion is not provided due to the restriction of the press work.

As shown in FIGS. 6 and 7, the cross member 46 is provided with holes 46 b through which bolts are passed, respectively, at its four ends. 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. 8, 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.

At the time of assembly, first, the linear members 42 and 44 are installed as shown in FIG. 5, and then the cross member 46 shown in FIG. 6 is aligned as shown in FIG. Then, by screwing the bolt 49 into the weld nut 48 from the outer side of the enlarged portion 46c, the first oblique cross member 40 that crosses and extends in an X shape as a whole is formed.
With such an assembling method, first, for example, after the catalyst 7 and the exhaust pipe 9 shown in FIG. 5 are installed, the X-shaped first 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. 9, the first oblique cross member 40, the floor panel 6, A connection structure with the two cross member 24 will be described. FIG. 9 shows a first oblique cross member, a floor panel, No. 1 according to the first embodiment of the 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 first 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 first oblique cross member 40 overlap each other is joined to each other by welding with the floor panel 6 interposed therebetween.

Next, a specific structure of the second oblique cross member will be described with reference to FIGS. 1 and 2.
As shown in FIGS. 1 and 2, the second oblique cross member 50 includes two linear members 52. Each of these linear members 52 has a hat-shaped cross section (not shown) that opens upward. 3 In the portion on the front side of the cross member 32, flange portions (not shown) formed on the left and right sides of the upper portion are combined with the lower surface portion of the floor panel 6 and configured as a frame with a closed cross section. ing.
One end portions of these two linear members 52 are respectively coupled to the B pillar 28 and the coupling portion 30 of the side sill 12 in the same manner as the linear member 44 of the first oblique cross member 40 described above. On the other hand, those other end portions are No. The four cross members 34 are coupled to an intermediate portion in the vehicle width direction.
Further, as shown in FIG. 3 cross member 32 and No. 3 The four cross members 34 are coupled to the lower surface portion. No. The 4 cross member 34 is 3 is provided at a position higher than the cross member 32, the straight member 52 of the second oblique cross member 50 is No. 3 cross member. The three cross members 32 are bent upward at the rear side.

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, in addition to the front side frame, the side sill, the rear side frame, and the cross member, since the front oblique cross member and the rear oblique cross member that extend obliquely in plan view are provided, the rigidity of the vehicle In addition, the strength can be increased. In particular, it works effectively against a side collision. In other words, the front side frame 2 has a first oblique cross member 40 that connects the rear end portion of the front side frame 2 to the B pillar 28 and the connecting portion 30 of the side sill 12 on the opposite side in the vehicle width direction. And the connecting portion 30 of the side sill 12, And a second oblique cross member 50 connecting the intermediate portion 34a of the four cross member 34. At the time of a side collision, the first oblique cross member 40 and the second oblique cross member 50 can effectively receive a side collision load.
Here, the deformation of the vehicle body at the time of a side collision by the conventional structure will be described. First, at the time of a side collision, the B pillar 28 falls inward, and as a result, the side sill 12 is twisted by the B pillar 28. Then, it is deformed so that the floor panel 6 near the B pillar 28 is turned up, and then the CAS analysis is performed so that the side sill 12 is deformed so as to be bent inward and the vehicle body is deformed so as to bite into the vehicle interior. It has become clear. In such a case, conventionally, the No. 1 connecting the side sill 12 and the floor tunnel 8 is used. Only the cross member 24 could accept the load at the time of a side collision.

  On the other hand, in the present invention, since both the first oblique cross member 40 and the second oblique cross member 50 are coupled to the connecting portion 30 between the B pillar portion 28 and the side sill 12, B While suppressing the twist of the pillar 28 and the side sill 12, the collision load at the time of a side collision can be distributed to the B pillar 28 and the side sill 12. The first oblique cross member 40 is connected to the front side frame 2, and the second oblique cross member 50 is a No. 1 cross member. Since it is connected to the four cross members 34, the side impact load can be distributed to these members. And No. The side impact load shared by the four cross members 34 is further distributed to the rear side frame 16. As described above, instead of the floor tunnel 8 as in the prior art, the front side frame 2, Other strength members such as the four cross member 34 and the rear side frame 16 can effectively receive the load. Further, the presence of the first oblique cross member 40 and the second oblique cross member 50 extending obliquely on the floor panel 6 prevents the floor panel 6 from being turned up and the side sill 12 from being folded internally. I can do it.

  Further, according to the first embodiment of the present invention, since the first oblique cross member 40 is the X-shaped members 42, 44, the members 42, 44 extending obliquely with respect to the torsion of the entire vehicle body. As a result, the axial force that can be received increases, and the torsional rigidity of the vehicle body, in particular, 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.

  Further, according to the first embodiment of the present invention, the joint 30 of the B pillar 28 and the side sill 12, Since it has the 2nd skew cross member 50 which couple | bonds with the intermediate part 34a of 4 cross member 34, and extends in V shape, when torsional force is added to a vehicle body, these axial force which each cross member 52 can receive is received The torsional rigidity of the vehicle body, in particular, the torsional rigidity of the rear part of the floor panel 6 can be improved. Further, in the conventional case, No. The load is transmitted to the 4 cross member 34 via the side sill 12 and the rear side frame 16, but according to the present invention, this No. 4 cross member 34 is caused by the second oblique cross member 50. 4 The load can be directly transmitted to the cross member 34. The load can be effectively received by the four cross member 34 and the rear side frame 16 to which the cross member 34 is coupled. The first oblique cross member 40 is No. 3 is also coupled to the cross member 32. The load can also be transmitted to the three cross members 32.

  Furthermore, according to the first embodiment of the present invention, the second oblique cross member 50 has a middle portion of No. 2 in the middle. 3 is coupled to the lower surface of the cross member 32, and further, The four cross members 34 are coupled to the intermediate portion 34a. Thus, since the 2nd diagonal cross member 50 is couple | bonded with the two cross members 32 and 34, a side impact load can be disperse | distributed effectively. Further, the second oblique cross member 50 is No. No. 3 on the rear side of the cross member 32. The four cross members 34 are extended. Accordingly, the second oblique cross member 50 extends at an angle close to the direction in which the side sill 12 extends, thereby suppressing the floor panel from turning up at the time of a side collision.

  Furthermore, according to the first embodiment of the present invention, the front side frame 2 and the side sill 12 are connected by the torque box 10 having a predetermined closed cross section. Further, the first oblique cross member 40 connects the rear end portions 2a of the pair of left and right front side frames 2 to the B pillar 28 and the coupling portion 30 of the side sill 12 provided at the intermediate portion in the longitudinal direction of the vehicle body. Yes. Such a first oblique cross member 40 connects the front side frame 2 and the side sill 12 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 side sill 12 (the side sill far from the front side frame 2) by the first oblique cross member 40.

Here, in the conventional cross beam structure, the input load received by the front side frame 2 at the time of an offset collision is transmitted only to the side sill on the side close to the front side frame 2 receiving the load. That is, there was almost no load sharing to the other side sill. On the other hand, as in the first embodiment of the present invention, the front side frame 2 and the pair of left and right side sills 12 are distributed by distributing the load to the opposite side sills 12 that do not contribute much to the load sharing in the prior art. In this way, the load energy can be received efficiently and the impact energy at the time of offset collision can be absorbed.
Further, at the time of a side collision, the input load received by the side sill 12 can be received by the first oblique cross member, and further, the load can be received by the other side sill 12 and the front side frame 2. As a result, the side sill 12 and the first oblique cross member 40 can efficiently receive the load and absorb the impact energy.
Further, according to the first embodiment of the present invention, the input load received by the side sill 12 at the time of a side collision can also be received by the second oblique cross member 50. As a result, No. 1 in which the side sill 12, the second oblique cross member 50, and the second oblique cross member 50 are connected to each other. The four cross members 34 can efficiently receive a load and absorb impact energy.

  Further, according to the first embodiment of the present invention, the first oblique cross member 40 includes the rear end portion of the front side frame 2 and the joint portion 30 of the B pillar 28 and the side sill 12 on the opposite side in the vehicle width direction. And In this way, by connecting the first oblique cross member 40 to the joint portion 30 of the B pillar 28 and the side sill 12, the three members of the first oblique cross member 40, the side sill 12, and the B pillar 28 are located at the same location. Since they are coupled, the vehicle body rigidity can be improved. Here, when an input load to the first oblique cross member 40 is transmitted to the side sill 12 at the time of a front collision, the side sill 12 may be deformed so as to spread outward in the vehicle width direction due to the transmitted load. However, in the embodiment of the present invention, since the rear end portion of the first oblique cross member 40 is coupled to the B pillar 28 and the connecting portion 30 of the side sill 12, such deformation that the side sill 12 spreads out. Can be suppressed. Furthermore, the overall rigidity around the passenger compartment is also improved.

  Further, according to the first embodiment of the present invention, since the first oblique cross member 40 is the X-shaped members 42, 44, the members 42, 44 extending obliquely with respect to the torsion of the entire vehicle body. As a result, the axial force that can be received increases, and the torsional rigidity of the vehicle body, in particular, 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, 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 each other 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. 10 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. 11 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.

First, the configuration of the oblique cross member according to the second embodiment of the present invention will be described with reference to FIGS. As in the first embodiment, the skew cross member is a frame member that extends obliquely with respect to both the vehicle longitudinal direction and the vehicle width direction in plan view, in addition to the members extending in the vehicle longitudinal direction and the vehicle width direction.
First, the configuration of the first oblique cross member 140 will be described.
Also in the second embodiment, the first oblique cross member 140 is coupled to the rear end portion of the front side frame 2 at the inner portion in the vehicle width direction. The first oblique cross member 140 is composed of two cross members that intersect in an X shape as an overall shape. One of them extends from the rear end inner portion 2a of the front side frame 2 on the left side in the vehicle width direction to the opposite side, that is, the connecting portion 30 of the B pillar 28 and the side sill 12 on the right side in the vehicle width direction. Similarly, the other side of the first oblique cross member 140 is connected to the B pillar 28 and the side sill 12 on the opposite side, that is, the left side in the vehicle width direction, from the rear end inner portion 2a of the front side frame 2 on the right side in the vehicle width direction. It extends to the part 30. As described above, each of the first oblique cross members 140 connects the rear end portion of the front side frame 2 to the connecting portion 30 of the B pillar 28 and the side sill 12 on the opposite side in the vehicle width direction.

  Similarly to the first embodiment, the first oblique cross member 140 in the second embodiment also has two cross-sectionally opened hat-like shapes extending from the rear end inner portion 2a of the front side frame 2. And two linear members 144 extending from the coupling portion 30 of the B pillar 28 and the side sill 12. Similarly to the first embodiment, the four linear members 42 and 44 are connected to each other by the cross member 146, and the first oblique cross member 140 extending in an X shape as a whole is formed (FIG. 5). To FIG. 8).

Next, the configuration of the second oblique cross member 150 will be described.
A second oblique cross member 150 is coupled to the coupling portion 30 of the B pillar 28 and the side sill 12. The second oblique cross member 150 is composed of two cross members having a V shape as a whole. And one of them is No. from the B pillar 28 on the left side in the vehicle width direction and the connecting portion 30 of the side sill 12. The three cross members 32 extend to an intermediate portion 32a in the vehicle width direction. Similarly, the other side of the second oblique cross member 150 is connected to the B. pillar 28 on the right side in the vehicle width direction and the joint 30 of the side sill 12 with No. 2 The three cross members 32 extend to an intermediate portion 32a in the vehicle width direction. As described above, the second oblique cross member 150 includes the B pillar 28 and the coupling portion 30 of the side sill 12, and The intermediate portion 32a of the three cross member 32 is coupled.

  Similarly to the first embodiment, the second oblique cross member 150 in the second embodiment is also composed of two linear members 52 having a cross-sectional hat shape opened upward. These two linear members 152 are No. The intermediate portion 32a of the three cross members 32 and the connecting portion 30 of the B pillar 28 and the side sill 12 are connected to each other to form a second oblique cross member 150 extending in a V shape as a whole.

Next, the configuration of the third oblique cross member 160 will be described.
No. A third oblique cross member 160 is coupled to the intermediate portion 32 a in the vehicle width direction of the three cross members 32. The third oblique cross member 160 is composed of two cross members having a V shape as an overall shape. And one of them is No. No. 3 on the left side in the vehicle width direction from the vehicle width direction intermediate portion 32a of the cross member 32. The four cross members 34 and the connecting portions 34b of the rear side frame 16 are extended. Similarly, the other of the third oblique cross members 160 is No. No. 3 on the right side in the vehicle width direction from the vehicle width direction intermediate portion 32a of the cross member 32. The four cross members 34 and the connecting portions 34b of the rear side frame 16 are extended. As described above, the third oblique cross members 160 are respectively No. No. 3 cross member 32 in the vehicle width direction intermediate portion 32a; The 4 cross member 34 and the coupling portion 34a of the rear side frame 16 are coupled.

  Similarly to the second oblique cross member 140, the third oblique cross member 160 is also composed of two linear members 162. These two linear members 162 are No. The intermediate portion 34a of the 4 cross member 34, The fourth cross member 34 and the coupling portion 34a of the rear side frame 16 are connected to each other, and a third oblique cross member 160 extending in a V shape is formed as a whole.

Next, the function and effect of the second embodiment of the present invention will be described.
The operational effects of the second embodiment of the present invention are almost the same as those of the first embodiment. Here, the main points and the main differences from the first embodiment will be described.
According to the second embodiment of the present invention, similarly to the first embodiment, the first oblique cross member 140 and the second oblique cross member 150 are provided. The cross member 140 and the second oblique cross member 150 can effectively receive a side impact load. And these skew cross members 150 can suppress the turning-up of the floor panel 6 and the internal folding of the side sill 12 as described in the first embodiment.

  Further, as in the first embodiment, the first oblique cross member 140 is the X-shaped members 142 and 144, so that the torsional rigidity of the vehicle body, particularly the torsional rigidity of the floor panel 6 can be improved. I can do it. Furthermore, the bending deformation of the cross members 142, 144 themselves generated by receiving the load at the time of a forward collision can be suppressed from each other, and the load can be more reliably distributed.

  Furthermore, according to the second embodiment of the present invention, the second oblique cross member 150 extending in a V shape similarly to the first embodiment, and the third oblique cross member extending in a V shape behind the second oblique cross member 150. 160, the axial force that can be received by each of the members 152 and 162 is increased, and the torsional rigidity of the vehicle body, particularly the torsional rigidity of the rear portion of the floor panel 6 can be improved. Further, in the conventional case, No. 3 cross member 32 and No. 3 The load is transmitted to the 4 cross member 34 via the side sill 12 and the rear side frame 16. 3 cross member 32 and No. 3 4 The load can be directly transmitted to the cross member 34. 3 cross member 34, no. The four cross members 34 and the rear side frame 16 to which these cross members 32 and 34 are coupled can effectively receive the load.

It is the bottom view which looked at the lower body structure by a 1st embodiment of the vehicles of the present invention from the lower part. It is the perspective view which looked at the lower body structure by 1st Embodiment of the vehicle of this invention from diagonally downward. It is a perspective view which shows the structure of the connection part of the side sill, B pillar 28, and cross member by 1st Embodiment of this invention. FIG. 4 is a cross-sectional view showing a cross-sectional structure of a connecting portion of a side sill, a B pillar 28, and a cross member viewed along line IV-IV in FIG. 3. 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 first oblique cross member, the 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 B pillar and side sill joint (intermediate part in the vehicle longitudinal direction)
32 No. 3 cross member 34 4 cross member 34a 4 Cross member vehicle width direction intermediate portion 36 Wheel house 40 First oblique cross members 42 and 44 according to the first embodiment Linear member 46 of the first oblique cross member according to the first embodiment First oblique according to the first embodiment Cross member 50 of the row cross member Second skew cross member 52 according to the first embodiment Straight member 140 of the second skew cross member according to the first embodiment First skew cross members 142, 144 according to the second embodiment Linear member 150 of the first oblique cross member according to the embodiment Second oblique cross member 152 according to the second embodiment Linear member 160 of the second oblique cross member according to the second embodiment Third oblique cross according to the second embodiment Member 162 Linear member of second oblique cross member according to second embodiment

Claims (5)

A pair of left and right front side frames extending in the longitudinal direction of the vehicle;
A pair of left and right side sills connected to the rear portions of these front side frames and extending in the vehicle longitudinal direction at both edges of the passenger compartment floor;
A pair of left and right center pillars extending in the vehicle vertical direction so as to connect the vehicle front-rear direction intermediate portion of the side sill and the vehicle roof;
A pair of left and right rear side frames extending in the longitudinal direction of the vehicle;
A cross member extending in the vehicle width direction so as to connect the front end portions of the pair of left and right rear side frames and / or the pair of left and right side sills,
Before extending diagonally in plan view so as to connect the rear end portion of at least one of the pair of left and right front side frames and the connecting portion of the center pillar and the side sill on the opposite side to the front side frame. A partial cross member,
A rear oblique cross member extending obliquely in a plan view so as to connect at least one of the center pillar and the connecting portion of the side sill and an intermediate portion in the vehicle width direction of the cross member; The lower body structure of the vehicle. A pair of left and right front side frames extending in the longitudinal direction of the vehicle;
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 center pillars extending in the vehicle vertical direction so as to connect the vehicle front-rear direction intermediate portion of the side sill and the vehicle roof;
A pair of left and right rear side frames extending in the vehicle front-rear direction, the rear side portions overlapping with the rear wheel house in side view rather than the front end portion are formed in a narrower space between each other,
A cross member extending in the vehicle width direction so as to connect the narrowly spaced portions of the rear side frames with each other;
Before extending diagonally in plan view so as to connect the rear end portion of at least one of the pair of left and right front side frames and the connecting portion of the center pillar and the side sill on the opposite side to the front side frame. A partial cross member,
A rear oblique cross member extending obliquely in a plan view so as to connect at least one of the center pillar and the connecting portion of the side sill and an intermediate portion in the vehicle width direction of the cross member; The lower body structure of the vehicle.   3. The front skew cross member is provided in a pair of left and right, and these 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. Lower vehicle body structure of the described vehicle. 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 front skew cross members are coupled to the lower surface of the passenger compartment floor,
The portion where the pair of left and right front oblique cross members intersect with each other is constituted by a cross member formed in an X shape separate from the other portions, and this cross member is the floor in a side view. 4. The lower body structure of a vehicle according to claim 3, wherein the vehicle body extends under a tunnel and each end thereof is coupled to the other portion.   The rear oblique cross member is provided in a pair of left and right, both of which one end is coupled to the intermediate portion of the cross member in the vehicle width direction and the other end is coupled to the connecting portion of the center pillar and the side sill. The vehicle lower body structure according to any one of claims 1 to 4, wherein the vehicle body structure is a V-shaped member.

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