CN111605627B

CN111605627B - Vehicle lower structure

Info

Publication number: CN111605627B
Application number: CN202010021030.6A
Authority: CN
Inventors: 河合桂介; 望月晋荣
Original assignee: Suzuki Motor Corp
Current assignee: Suzuki Motor Corp
Priority date: 2019-02-22
Filing date: 2020-01-09
Publication date: 2022-06-21
Anticipated expiration: 2040-01-09
Also published as: FR3093065B1; JP2023010971A; JP7373138B2; DE102020101747A1; JP2020132051A; JP2023010972A; JP7185847B2; JP7414115B2; JP7373139B2; JP2023010970A; CN111605627A; FR3093065A1

Abstract

The present invention provides a vehicle lower section structure in which an end member of a lower cross member is joined to a rocker, a front side member, and a rear end portion of the front side member and a front end portion of the rear side member are arranged so as to overlap each other when viewed from the front of a vehicle, thereby facilitating transmission of a load in the vehicle front-rear direction and dispersion of the load. The vehicle lower structure includes: a rocker (3) provided at a vehicle width direction side portion of the floor; a side member (4) disposed adjacent to the rocker on the vehicle inner side of the rocker; and a lower cross member (5) provided below the floor, the side members having a front side member (41) and a rear side member (42), the lower cross member being joined to the front side member, wherein an end member (6) is joined to an end portion of the lower cross member on the outer side in the vehicle width direction, the end member being joined to the side sill, the front side member, and the rear side member, and a rear end portion (41a) of the front side member and a front end portion (42a) of the rear side member are arranged so as to overlap when viewed from the front of the vehicle.

Description

Vehicle lower structure

Technical Field

The present invention relates to a vehicle lower portion structure.

Background

Among conventional vehicle lower portion structures, there is a vehicle lower portion structure including: a rear seat cross member extending in the vehicle width direction; and front and rear floor side members extending in the vehicle front-rear direction and located at positions shifted in the vehicle width direction. In this vehicle lower portion structure, the rear seat cross member is connected to the front portion of the rear floor side member and the rear portion of the front floor side member, respectively, and the rib portion is provided in the side portion region on the vehicle width direction outer side of the rear seat cross member connected to the rear floor side member, whereby buckling deformation is promoted against input of an impact load from the vehicle side (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-107892

Disclosure of Invention

Problems to be solved by the invention

In this way, in the conventional vehicle lower portion structure described above, since the rear floor side member is connected to the side portion region on the vehicle transverse direction outer side of the rear seat cross member having the rib portion that promotes buckling deformation, there is a problem that the vehicle body rigidity is lowered, and when an impact load is input to the vehicle body, the load is not sufficiently transmitted to the vehicle body frame member such as the floor side member.

The present invention has been made in view of such circumstances, and an object thereof is to provide a vehicle lower portion structure that can promote transmission of an input load in the vehicle front-rear direction and dispersion of the load by joining an end member joined to an end portion on the vehicle width direction outer side of a lower side cross member to a rocker, a front side member, and a rear side member, and arranging a rear end portion of the front side member and a front end portion of the rear side member so as to overlap each other when viewed from the vehicle front.

Means for solving the problems

In order to solve the problems of the conventional techniques described above, the present invention provides a vehicle lower section structure including: a pair of left and right rocker beams provided on the vehicle width direction side portions of the floor panel and extending in the vehicle front-rear direction; a pair of side members that are disposed adjacent to the rocker on the vehicle inner side of the rocker and extend in the vehicle front-rear direction; and a lower cross member provided below the floor and extending in a vehicle width direction, the side members including a front side member and a rear side member provided at positions in front and rear of the vehicle, the lower cross member being joined to the pair of left and right front side members, wherein the lower cross member is provided with an end member joined to an end portion on an outer side in the vehicle width direction of the lower cross member, the end member being joined to the side sill, the front side member, and the rear side member, and a rear end portion of the front side member and a front end portion of the rear side member are arranged so as to overlap when viewed from a front of the vehicle.

ADVANTAGEOUS EFFECTS OF INVENTION

As described above, the vehicle lower portion structure of the present invention includes: a pair of left and right rocker beams provided on the vehicle width direction side portions of the floor panel and extending in the vehicle front-rear direction; a pair of side members that are disposed adjacent to the rocker on the vehicle inner side of the rocker and extend in the vehicle front-rear direction; and a lower cross member provided below the floor and extending in a vehicle width direction, the side members including a front side member and a rear side member provided at positions in front and rear of the vehicle, the lower cross member being joined to the pair of left and right front side members, the lower cross member being provided with an end member joined to an end portion of the lower cross member on an outer side in the vehicle width direction, the end member being joined to the side sill, the front side member, and the rear side member, a rear end portion of the front side member and a front end portion of the rear side member being arranged so as to overlap each other when viewed from a front of the vehicle.

That is, in the vehicle lower portion structure of the present invention, the end members joined to the lower side cross member are joined to the rocker, the front side member, and the rear side member, respectively, and the rear end portion of the front side member and the front end portion of the rear side member overlap each other when viewed from the front of the vehicle.

In the vehicle lower portion structure of the present invention, since the load from the outside is input to the rear side frame whose rigidity with respect to the vehicle width direction and the vehicle front-rear direction is improved by the end member or the like joined to the lower side cross member, it is possible to promote the dispersion of the load.

Drawings

Fig. 1 is a perspective view of a floor panel, a rocker, a side member, a power supply member, and a cross member as viewed from obliquely below a vehicle in a vehicle lower portion structure according to an embodiment of the present invention.

Fig. 2 is a perspective view showing a state where the power supply member is removed, with the Z portion in fig. 1 being enlarged.

Fig. 3 is an enlarged perspective view of the end member and the peripheral portion of the lower cross member provided under the floor in fig. 1, as viewed obliquely from below the vehicle with the power supply member and the cross member removed.

Fig. 4 is a plan view showing an end member of the lower cross member and a peripheral portion thereof in fig. 3.

Fig. 5 is a perspective view of the end member of the lower cross member and its peripheral portion in fig. 3, with the rear side member omitted, viewed obliquely from below and behind the vehicle.

Fig. 6 is a perspective view of the end member of the lower cross member and its peripheral portion in fig. 3, as viewed obliquely from the front and downward of the vehicle.

Fig. 7 is a side view of the end member of the lower cross member and its peripheral portion in fig. 3, as viewed from the outside of the vehicle side.

Description of the reference numerals

1. A front floor; 2. a rear floor; 3. a lower edge beam; 4. a stringer; 5. a lower side beam; 6. an end member; 8. a cross beam; 8a, end portions in the vehicle width direction; 10. a power supply member; 11. a floor side surface portion; 12. a floor inclined plane portion; 13. a floor center face; 31. a front lower edge beam; 32. a rear rocker; 41. a front longitudinal beam; 41a, a rear end portion; 42. a rear longitudinal beam; 42A, a beam joint; 42a, a front end portion; 42b, a lower surface portion; 42c, side surface parts; 43. a beam joint bracket; 51. a rear step wall; 61. a rear wall of the end member; 61a, a rear side joint portion; 62. a front wall of the end member; 62a, a front side joint part; 63. an extension portion; 63a, inclined portion.

Detailed Description

The present invention will be described in detail below based on the illustrated embodiments.

In the drawings, the arrow Fr direction indicates the vehicle front, the arrow L direction indicates the vehicle lower side, and the arrow I direction indicates the vehicle width direction inner side. The arrow X direction indicates the vehicle width direction, and the arrow Y direction indicates the vehicle front-rear direction.

Fig. 1 to 7 are views showing a vehicle lower portion structure according to an embodiment of the present invention. As shown in fig. 1 and 2, the vehicle lower portion structure of the present embodiment includes: a front floor panel 1 and a rear floor panel 2, the front floor panel 1 and the rear floor panel 2 constituting a floor panel, being developed in a vehicle width direction and a vehicle front-rear direction, and being disposed at a vehicle front-rear position in the vehicle front-rear direction; a pair of left and right rocker beams 3 provided on the vehicle width direction side portions of the front floor 1 and the rear floor 2 and extending in the vehicle front-rear direction; a pair of left and right side members 4 disposed on the vehicle inner side of the rocker 3 adjacent to the rocker 3 and extending in the vehicle front-rear direction; and a lower cross member 5 provided below the front floor 1 and the rear floor 2 and extending in the vehicle width direction, the front floor 1 being provided at a position lower than the rear floor 2 in the vehicle vertical direction.

As shown in fig. 6, the front floor 1 of the present embodiment includes: a floor side surface portion 11 that is located on the vehicle width direction outer side and is joined to the rocker 3; a floor inclined surface portion 12 that is located further toward the vehicle width direction inner side than the floor side surface portion 11 and that is inclined upward toward the vehicle inner side; and a floor center surface portion 13 that is located on the vehicle width direction inner side of the floor inclined surface portion 12 and is flat in the vehicle width direction. Therefore, the front floor 1 has a structure that is raised upward of the vehicle, and the floor center surface portion 13 is provided at a position higher than the floor side surface portions 11 and the floor inclined surface portions 12.

In the vehicle lower portion structure of the present embodiment, as shown in fig. 1 to 7, the rocker 3 has a front rocker 31 and a rear rocker 32, and the front rocker 31 and the rear rocker 32 are provided at positions in the front and rear of the vehicle and have end portions joined to each other. The side member 4 has a front side member 41 and a rear side member 42 provided at positions in the front and rear of the vehicle, and the lower side member 5 is joined to the pair of left and right front side members 41. The rear side member 42 extends to be positioned further toward the vehicle inner side toward the vehicle rear side, and a suspension arm attachment portion 40 is provided by being joined to a lower surface portion 42b, which will be described later, positioned at a middle portion in the vehicle front-rear direction, and the suspension arm attachment portion 40 is further joined to a side surface of the rear rocker 32.

As shown in fig. 2 to 7, the lower cross member 5 of the present embodiment is provided with an end member 6 disposed on the vehicle transverse direction outer side of the lower cross member 5, and the inner end of the end member 6 is joined to the vehicle transverse direction outer end of the lower cross member 5. The end member 6 of the present embodiment is joined to the front rocker 31 and the rear rocker 32 of the rocker 3, and to the front side member 41 and the rear side member 42 of the side member 4, and the rear end portion 41a of the front side member 41 and the front end portion 42a of the rear side member 42 are arranged so as to overlap when viewed from the front of the vehicle. That is, the rear side member 42 is configured to have an improved rigidity in the vehicle width direction and the vehicle front-rear direction. The end member 6 is formed by bending into a shape corresponding to the shapes of the rocker 3 and the side member 4, and thus the end member 6 has a structure capable of being overlapped with the rocker 3 and the side member 4 to be joined.

In the vehicle lower portion structure of the present embodiment, the load applied to the rocker 3 and the side member 4 is smoothly transmitted in the vehicle front-rear direction, and the load is input to the rear side member 42 having an improved rigidity in the vehicle width direction and the vehicle front-rear direction, so that the load dispersion is promoted. Further, as the rigidity of the rear side member 42 increases, vibration input from the suspension arm attachment portion 40 to the rear side member 42 is reduced, and floor vibration and road noise are improved. Further, when the end member 6 is formed by a member independent from the lower cross member 5, the rigidity of the joint portion with the rocker 3 and the side member 4 can be easily controlled by changing the plate thickness, and the forming process can be simplified.

As shown in fig. 3 to 7, the end member 6 of the present embodiment is joined to the front side frame 41 at a vehicle front side portion, and has a rear wall 61 joined to the rear rocker 32 of the rocker 3 at a vehicle rear side of the end member 6. The end member 6 and the rear side member 42 are joined in a state where the rear wall 61 and the rear side member 42 are overlapped. The rear wall 61 extends in the vehicle front-rear direction and the vehicle vertical direction, and is configured to improve the rigidity of the end member 6 with respect to the vehicle width direction and the vehicle vertical direction by engaging the rear wall 61 of the end member 6 with the rear rocker 32. In addition, the end members 6 having high rigidity are joined to the front rocker 31 and the rear rocker 32 of the rocker 3, thereby obtaining a configuration having further improved rigidity. As shown in fig. 7, a block member (バルク member, japanese) 7 having a side wall portion 7a extending toward the vehicle rear side on the vehicle inner side and the vehicle outer side is disposed along the vehicle vertical direction at a portion of the rear wall 61 of the end member 6, and the side wall portion 7a of the block member 7 is joined to the rear side frame 42 and is joined to the rear wall 61 and the rear side frame 32. This further increases the rigidity of the portion of the end member 6 where the rear wall 61 is located.

Further, the rear side member 42 has a larger cross-sectional area where the rear side member 42 is joined to the end member 6 than the front side member 41, but is joined to the rear side member 42 via the rear wall 61, and therefore, has a structure that does not affect the joint cross-sectional area where the front side member 41 is joined.

Further, as shown in fig. 3 and 5, the rear wall 61 of the end member 6 of the present embodiment has a rear side joining portion 61a joined at the rear side step wall 51 of the lower side cross member 5 located on the vehicle rear side, and a rear side edge line R1 extends smoothly in the vehicle width direction at a lower side corner portion of the rear wall 61. Further, the rear-side step wall 51 extends to the flat floor center face portion 13 of the front floor 1 located on the vehicle width direction inner side. Thereby, the load input to the end member 6 is transmitted to the rear step wall 51 of the lower cross member 5. Moreover, the rear wall 61 has high rigidity with respect to the vehicle width direction and the vehicle up-down direction, and is also joined to the rear-side step wall 51, and therefore has higher rigidity with respect to the vehicle width direction and the vehicle up-down direction. Further, as the rigidity of the lower side member 5 increases, the rigidity of the rear side member 42 also increases.

On the other hand, as shown in fig. 3 to 6, a front wall 62 extending in the vehicle vertical direction is formed on the vehicle front side of the end member 6, and this front wall 62 has a front-side engaging portion 62a that engages with the front-side step wall 52 of the lower cross member 5 on the vehicle front side. Also, at the lower side corner portion of the front wall 62, the front side ridge line R2 extends smoothly in the vehicle width direction and extends along the front side member 41.

In the vehicle lower portion structure of the present embodiment, as shown in fig. 3 to 6, the lower cross member 5 is disposed above the front side member 41 in the vehicle, and a floor inclined surface portion 12 that is inclined upward from the front side member 41 toward the vehicle interior side is provided at a boundary portion of the front floor 1 where the lower cross member and the front side member 41 are joined. On the other hand, the end member 6 has an extended portion 63 extending toward the lower cross member 5, the extended portion 63 engaging with the lower cross member 5 at the position of the floor inclined surface portion 12. That is, since the extended portion 63 is located within the range of the floor inclined surface portion 12, the front side member 41 is supported from the vehicle lower side by the lower side cross member 5 and the end member 6.

In the vehicle lower portion structure of the present embodiment, as shown in fig. 3 to 6, the extending portion 63 located at the floor inclined surface portion 12 has an inclined portion 63a that is inclined toward the vehicle lower side as it goes toward the vehicle outer side, and this inclined portion 63a is formed continuously to the front side member 41 (or the rear side member 42). Thus, the rigidity with which the lower side member 5 supports the front side member 41 (or the rear side member 42) is improved not only in the vehicle width direction but also in the vehicle vertical direction.

In the vehicle lower portion structure of the present embodiment, as shown in fig. 1, a power supply member (for example, a battery or the like) 10 is provided below the front floor panel 1 and the rear floor panel 2. That is, the position of the floor center surface portion 13 of the front floor 1 is raised upward in the vehicle, the height position of the floor center surface portion 13 is located above the floor side surface portion 11 and the floor inclined surface portion 12 in the vehicle, and the power supply member 10 is configured to be able to be housed and mounted in a space formed below the floor center surface portion 13. The power supply member 10 stored in the space below the floor center surface portion 13 is arranged so as to overlap with the front rocker 31 and the rear rocker 32 of the rocker 3 when viewed from the side of the vehicle, and is supported by a plurality of cross members 8 extending in the vehicle width direction. Therefore, even with the improved structure of the front floor 1, the power supply member 10 can be protected from the impact load at the time of a side collision. The cross member 8 is formed to have a vehicle width direction dimension larger than that of the power supply member 10, and is arranged at a predetermined interval in the vehicle front-rear direction using the number that can correspond to the vehicle front-rear direction length of the power supply member 10.

On the other hand, the rear side member 42 of the present embodiment is provided with a cross member joint portion 42A that joins the vehicle width direction end portion 8a of the cross member 8 by a fastening member or the like, and the cross member joint portion 42A is disposed at a position that is within the vehicle front-rear direction range of the rocker 3 when viewed from the vehicle lower side. That is, in the vehicle lower portion structure of the present embodiment, the end member 6, the beam joint portion 42A, and the suspension arm attachment portion 40 are arranged in this order from the vehicle front toward the vehicle rear.

Thus, the end portion 8a of the cross member 8 is joined to the rear side member 42 via the cross member joint portion 42A, and therefore, a structure is obtained in which the rigidity of the rear side member 42 in the vehicle width direction is improved. The cross member joint portion 42A is disposed at a position in the vehicle front-rear direction range of the rocker 3, and is configured to join the rigid member to the rear side member 42 from both sides in the vehicle width direction.

In the vehicle lower portion structure of the present embodiment, as shown in fig. 3 and 4, the rear side member 42 includes a lower surface portion 42b located closer to the vehicle lower side and a side surface portion 42c located in the vehicle width direction. A beam joint bracket 43 is provided at the beam joint 42A, and the beam joint bracket 43 is joined to the lower surface portion 42b and the side surface portion 42c of the rear side member 42. Therefore, the cross member joint portion bracket 43 is configured such that the upper surface of the end portion 8a of the joint cross member 8 has a quadrangular shape, the surrounding side walls extend in the vehicle vertical direction, the upper portion 43a on the vehicle inner side extends to the side surface portion 42c of the rear side member 42 and overlaps therewith, and the

upper portions

43b and 43c on the vehicle front and rear sides and the upper portion 43d on the vehicle outer side are formed to bend along the lower surface portion 42b of the rear side member 42 and overlap therewith, so that the overlapping portion is joined.

Therefore, in the vehicle lower portion structure of the present embodiment, the rigidity in the vehicle width direction and the vehicle front-rear direction is improved by the cross member joint brackets 43 being joined to the lower surface portions 42b of the rear side frames 42, and the rigidity in the vehicle front-rear direction and the vehicle vertical direction is improved by the cross member joint brackets 43 being joined to the side surface portions 42c of the rear side frames 42, thereby facilitating the transmission of load to the rear side frames 42.

In the vehicle lower portion structure of the present embodiment, as shown in fig. 2 to 4, a jack-up bracket (japanese: ジャッキアップブラケット)9 is provided on the vehicle transverse direction outer side of the cross member joint portion 42A, and the jack-up bracket 9 is joined to the rear rocker 32 and the rear side member 42. This concentrates the joint portions of the various members in the installation range of the beam joint portion 42A, improves the rigidity of the peripheral portion of the beam joint portion 42A in the vehicle width direction, and provides a structure that promotes the load transmission in the peripheral portion of the beam joint portion 42A.

As described above, the vehicle lower portion structure according to the embodiment of the present invention includes: a pair of left and right rocker beams 3 provided on the vehicle width direction side portions of the floor (front floor 1 and rear floor 2) and extending in the vehicle front-rear direction; a pair of left and right side members 4 disposed on the vehicle inner side of the rocker 3 adjacent to the rocker 3 and extending in the vehicle front-rear direction; and a lower cross member 5 provided below the

floor panels

1, 2 and extending in the vehicle width direction. The side member 4 has a front side member 41 and a rear side member 42 provided at positions in the front and rear of the vehicle, and the lower side member 5 is joined to the pair of left and right front side members 41. Further, the lower cross member 5 is provided with an end member 6 joined to an end portion of the lower cross member 5 on the vehicle transverse direction outer side, and the end member 6 is joined to the rocker 3, the front side member 41, and the rear side member 42. The rear end portion 41a of the front side member 41 and the front end portion 42a of the rear side member 42 are arranged to overlap each other when viewed from the front of the vehicle.

Therefore, in the vehicle lower portion structure of the present embodiment, the end member 6 joined to the lower side cross member 5 is joined to the rocker 3, the front side member 41, and the rear side member 42, respectively, and the rear end portion 41a of the front side member 41 and the front end portion 42a of the rear side member 42 overlap with each other as viewed from the vehicle front, so that when a load is input to the rocker 3 or the like from the vehicle side or the like, the input load can be quickly and reliably transmitted in the vehicle front-rear direction, and the load transmission in the vehicle front-rear direction can be promoted.

In the vehicle lower portion structure of the present embodiment, the rigidity of the rear side frame 42 in the vehicle width direction and the vehicle front-rear direction is improved by the end member 6 joined to the lower side cross member 5, and a load from the outside is input to the highly rigid rear side frame 42, so that the load dispersion effect can be improved.

In the vehicle lower portion structure of the present embodiment, the vehicle front side portion of the end member 6 is joined to the front side member 41, the vehicle rear side of the end member 6 has the rear wall 61 joined to the rocker 3, and the end member 6 and the rear side member 42 are joined in a state where the rear wall 61 and the rear side member 42 are overlapped.

Therefore, in the vehicle lower portion structure of the present embodiment, since the rigidity of the end member 6 in the vehicle width direction and the vehicle vertical direction is improved, by joining the high-rigidity end member 6 to the front rocker 31 and the rear rocker 32 of the rocker 3, the rigidity can be further improved, and the input load can be efficiently transmitted to and dispersed from the peripheral components.

Further, in the vehicle lower portion structure of the present embodiment, the rear wall 61 of the end member 6 has a rear side engaging portion 61a that is engaged at the rear side step wall 51 of the lower side cross member 5 on the vehicle rear portion side, and the rear side step wall 51 extends to the flat floor center face portion 13 on the vehicle width direction inner side of the front floor 1 as the floor.

Therefore, according to the vehicle lower portion structure of the present embodiment, the load input to the end member 6 can be smoothly transmitted to the rear side step wall 51 of the lower cross member 5. Further, the rear wall 61 has high rigidity in the vehicle width direction and the vehicle vertical direction, and is also joined to the rear step wall 51, so that it is possible to further improve the rigidity in the vehicle width direction and the vehicle vertical direction. Further, the rigidity of the rear side member 42 can be further improved by improving the rigidity of the lower side cross member 5.

In the vehicle lower portion structure of the present embodiment, the lower cross member 5 is disposed above the front side member 41 in the vehicle, and a floor inclined surface portion 12 that inclines upward from the front side member 41 toward the vehicle inner side is provided at a boundary portion of the front floor 1 (floor panel) where the lower cross member 5 and the front side member 41 are joined. The end member 6 has an extended portion 63 extending toward the lower cross member 5, the extended portion 63 being joined to the lower cross member 5 at the position of the floor inclined surface portion 12.

Therefore, in the vehicle lower portion structure of the present embodiment, since the extension portion 63 is located within the range of the floor inclined surface portion 12, the front side member 41 can be supported from the vehicle lower side by the lower side cross member 5 and the end member 6, the rigidity of the front side member 41 can be improved, and the effect of transmitting the input load in the vehicle front-rear direction can be improved.

Further, in the vehicle lower portion structure of the present embodiment, the extension portion 63 located at the floor inclined surface portion 12 has an inclined portion 63a inclined more toward the vehicle lower side toward the vehicle outer side, and the inclined portion 63a is continuously formed to the front side member 41 (or the rear side member 42). Therefore, according to the vehicle lower portion structure of the present embodiment, the rigidity with which the front side frame 41 (or the rear side frame 42) is supported by the lower side cross member 5 is improved not only in the vehicle width direction but also in the vehicle vertical direction, and the effect of dispersing the input load can be improved.

In the vehicle lower portion structure of the present embodiment, the power supply member 10 is provided below the front floor panel 1 and the rear floor panel 2 (floor panel), and the power supply member 10 is arranged so as to overlap with the rocker 3 when viewed from the side of the vehicle and is supported by the cross member 8 extending in the vehicle width direction. The rear side member 42 is provided with a cross member joint portion 42A that joins the cross member 8, and the cross member joint portion 42A is disposed at a position that is within the vehicle front-rear direction range of the rocker 3 when viewed from below the vehicle.

Therefore, according to the vehicle lower portion structure of the present embodiment, since the end portion 8a of the cross member 8 is joined to the rear side member 42 via the cross member joint portion 42A, the rigidity of the rear side member 42 with respect to the vehicle width direction can be improved. Further, since the cross member joint portion 42A is disposed at a position in the vehicle front-rear direction range of the rocker 3 and the rigid members are joined to the rear side frame 42 from both sides in the vehicle width direction, the rigidity of the rear side frame 42 in the vehicle front-rear direction can be increased, and the load input to the rear side frame 42 can be efficiently transmitted in the vehicle front-rear direction.

In the vehicle lower portion structure of the present embodiment, the rear side member 42 includes a lower surface portion 42b located closer to the vehicle lower side and a side surface portion 42c located in the vehicle width direction. A beam joint bracket 43 is provided at the beam joint 42A, and the beam joint bracket 43 is joined to the lower surface portion 42b and the side surface portion 42c of the rear side member 42.

Therefore, in the vehicle lower portion structure of the present embodiment, the rigidity of the rear side frame 42 in the vehicle width direction and the vehicle front-rear direction can be increased by joining the cross member joint brackets 43 to the lower surface portions 42b of the rear side frame 42, and the rigidity of the rear side frame 42 in the vehicle front-rear direction and the vehicle vertical direction can be increased by joining the cross member joint brackets 43 to the side surface portions 42c of the rear side frame 42, so that the transmission of load to the rear side frame 42 can be promoted.

While the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and changes can be made based on the technical idea of the present invention.

For example, the size and shape of the power supply member 10 are not limited to those shown in fig. 1, and power supply members having other sizes and shapes may be mounted according to the type of the vehicle to which the power supply member is applied, as long as the power supply member can be supported by the cross member 8.

Claims

1. A vehicle lower section structure, comprising: a pair of left and right rocker beams provided on the vehicle width direction side portions of the floor panel and extending in the vehicle front-rear direction; a pair of side members that are disposed adjacent to the rocker on the vehicle inner side of the rocker and extend in the vehicle front-rear direction; and a lower cross member provided below the floor panel and extending in a vehicle width direction,

the side members include a front side member and a rear side member provided at front and rear positions of the vehicle, the lower cross member is joined to the pair of left and right front side members,

the vehicle lower portion structure is characterized in that,

the lower cross member is provided with an end member joined to an end portion of the lower cross member on the vehicle width direction outer side, the end member being joined to the side sill, the front side member, and the rear side member so as to overlap with the side sill, the front side member, and the rear side member, and a rear end portion of the front side member and a front end portion of the rear side member being arranged so as to overlap with each other when viewed from the vehicle front.

2. The vehicle substructure according to claim 1,

the end member has a vehicle front side portion joined to the front side member, a rear wall joined to the rocker at a vehicle rear side of the end member, and the end member and the rear side member are joined together in a state where the rear wall and the rear side member overlap.

3. The vehicle substructure according to claim 2,

the rear wall has a rear-side engaging portion for engaging a rear-side step wall that is located on a vehicle rear portion side of the lower cross member and that extends to a flat floor center face portion of the floor that is located on a vehicle width direction inner side.

4. The vehicle substructure according to any of claims 1 to 3,

the lower cross member is disposed above the front side member in the vehicle, and a floor inclined surface portion inclined upward as the front side member extends inward in the vehicle is provided at a boundary portion of the floor where the lower cross member and the front side member are joined,

the end member has an extension extending toward the lower-side cross member, the extension being joined to the lower-side cross member at the position of the floor inclined surface portion.

5. The vehicle infrastructure according to claim 4,

the extended portion located at the floor inclined surface portion has an inclined portion that extends further toward the vehicle outer side and is inclined further toward the vehicle lower side, and the inclined portion is continuously formed to the front side member or the rear side member.

6. The vehicle substructure according to claim 1,

a power supply member that is disposed below the floor panel so as to overlap the rocker when viewed from the side of the vehicle and is supported by a cross member that extends in the vehicle width direction,

the rear side member is provided with a cross member joint portion that joins the cross member, and the cross member joint portion is disposed at a position that is within a vehicle front-rear direction range of the rocker when viewed from below the vehicle.

7. The vehicle substructure according to claim 6,

the rear side member has a lower surface portion located at a position closer to a vehicle lower side and a side surface portion located at a position in a vehicle width direction, and the cross member joint portion is provided with a cross member joint portion bracket that is joined to the lower surface portion and the side surface portion of the rear side member.