JP2021088364A - Vehicle lower structure - Google Patents

Abstract

To obtain a vehicle lower structure that is able to hinder inward break of a rocker by absorbing impact energy more effectively.SOLUTION: In a rocker 14, an outer part 22 and an inner part 24 are integrally formed, and impact absorbing parts 38, 40 are formed integrally with the outer part 22 and inner part 24. This eliminates the need for a rib or the like for preventing displacement of impact absorbing members in the event of impact application. Therefore, residual crash due to formation of the rib does not occur. Thus, impact energy due to collision load F can effectively be absorbed and, even in the event that large load is locally input to the rocker 14 as in a case of side collision with a pole, inward break of the rocker 14 can be hindered. In other words, by hindering residual crash of the impact absorbing parts 38, 40, impact energy can be absorbed more effectively and inward break of the rocker 14 can be hindered.SELECTED DRAWING: Figure 2

Description

The present invention relates to a vehicle lower structure.

Patent Document 1 below discloses a technique relating to a vehicle lower structure that supports a battery unit, which is one of the driving force supply devices, on the lower side of the vehicle on the floor panel. Specifically, in this prior art, a square tubular battery side frame is arranged between the rocker and the battery unit and is mounted adjacent to the rocker and the battery unit.

On the other hand, when an impact load is input to the rocker due to a side collision of the vehicle and the rocker deforms toward the inside in the vehicle width direction (inside the rocker), a tensile force acts on the inside of the rocker in the vehicle width direction. In the above prior art, as described above, since the battery side frame is provided adjacent to the rocker, a compressive force acts on the rocker side of the battery side frame.

That is, in the above prior art, in the rocker and the battery side frame, the stresses acting on each other cancel each other out between the tensile force and the compressive force acting on the portions adjacent to each other. As a result, deformation of the rocker and the battery side frame is suppressed, and intrusion of the rocker inward in the vehicle width direction (so-called inward bending) is suppressed.

Japanese Unexamined Patent Publication No. 2013-133064

However, when a large load is locally applied to the rocker as in the so-called pole side collision, the rocker may bend inward.

In consideration of the above facts, an object of the present invention is to obtain a vehicle lower structure capable of more effectively absorbing impact energy and suppressing inward bending of the rocker.

The vehicle lower structure according to the first aspect of the present invention is arranged on both outer sides of the floor panel of the vehicle in the vehicle width direction, and a pair of rockers extending along the vehicle front-rear direction are formed in the vehicle width direction. An inner portion that is integrally formed with the outer portion and is located inside in the vehicle width direction and forms a closed cross section with the outer portion, and an inner portion that is integrally formed with the outer portion and the inner portion. It is configured to include a first shock absorbing portion formed and bridged in the vehicle width direction between the outer portion and the inner portion in the closed cross-sectional portion.

In the vehicle lower structure according to the present invention according to claim 1, rockers are arranged on both outer sides of the floor panel of the vehicle in the vehicle width direction, and each rocker extends along the vehicle front-rear direction. There is. Here, in the rocker, an outer portion located outside in the vehicle width direction and an inner portion located inside in the vehicle width direction are integrally formed, and the outer portion and the inner portion form a closed cross-sectional portion. doing. The "integral formation" here means that the outer portion and the inner portion are integrally formed by extrusion processing, drawing processing, or the like.

Then, in the present invention, in the rocker, the outer portion and the inner portion are integrally formed, so that, for example, the rocker is formed by joining two panels of the outer portion and the inner portion, as compared with the case where the rocker is formed. The strength of the rocker itself can be increased.

Further, when the rocker joins the two panels of the outer portion and the inner portion, welding, fastening, etc. are required. However, in the present invention, the outer portion and the inner portion are integrally formed, so that these processes are performed. Is unnecessary, and the cost can be reduced accordingly.

Further, in the closed cross section of the rocker, the first shock absorbing portion is integrally formed together with the outer portion and the inner portion, and is bridged between the outer portion and the inner portion in the vehicle width direction in the closed cross section. Therefore, a part of the impact load input to the rocker at the time of a side collision of the vehicle (hereinafter referred to as "the side collision of the vehicle") is transmitted inward in the vehicle width direction via the first impact absorbing portion. It will be.

Generally, from the viewpoint of protecting the vehicle interior, the rigidity of the inside of the rocker in the vehicle width direction is high. Therefore, when the load is transmitted inward in the vehicle width direction via the first shock absorbing portion, a reaction force against the rocker is obtained. As a result, the first impact absorbing portion is plastically deformed and the impact energy is absorbed.

Here, for example, when the shock absorbing member is provided separately from the rocker as the shock absorbing member, the position of the shock absorbing member does not shift due to the impact when the shock absorbing member is arranged in the closed cross section of the rocker. Therefore, it is necessary to provide a rib or the like for restricting the movement of the shock absorbing member in the closed cross section.

When such a rib is provided in the closed cross section of the rocker, when an impact load is applied to the rocker and the impact absorbing member is plastically deformed, the rib may hinder the plastic deformation of the impact absorbing member. .. In this way, when the plastic deformation of the shock absorbing member is inhibited, so-called crushed residue is generated, and the amount of shock energy absorbed by the rocker is reduced by the amount of the crushed residue. That is, there is a possibility that the impact energy cannot be absorbed efficiently.

On the other hand, in the present invention, since the first shock absorbing portion is integrally formed with the outer portion and the inner portion, it is not necessary to provide ribs or the like, and it is possible to suppress the crushing residue of the first shock absorbing portion. it can. That is, it is possible to effectively absorb the impact energy due to the collision load, which suppresses the inward bending of the rocker even if a large load is locally applied to the rocker, such as a pole side collision. It becomes possible.

The vehicle lower structure according to the present invention according to claim 2 is the vehicle lower structure according to the present invention according to claim 1, wherein a storage battery is arranged on the lower side of the vehicle on the floor panel, and the first shock absorbing portion. Is arranged at a position overlapping the storage battery when viewed from the side of the vehicle.

Generally, a storage battery mounted on a vehicle is set to have high rigidity. Therefore, in the vehicle lower structure according to the second aspect of the present invention, the storage battery is arranged on the lower side of the vehicle on the floor panel, and the first shock absorbing portion is arranged at a position overlapping the storage battery in the side view of the vehicle. There is. As a result, a part of the impact load input to the rocker at the time of the side collision of the vehicle is transmitted to the storage battery side via the first impact absorbing unit.

As described above, since the storage battery is set to have high rigidity, when an impact load is input to the storage battery, a reaction force is obtained from the storage battery. As a result, the first impact absorbing portion is plastically deformed and the impact energy is absorbed. That is, it is possible to reduce the impact load even with a short stroke.

Further, the impact load transmitted to the storage battery via the first impact absorbing portion of the rocker obtains a reaction force from the storage battery to suppress the intrusion of the rocker inward in the vehicle width direction (so-called inward bending). Can be done.

Examples of the "storage battery" include a lithium ion battery, a nickel hydrogen battery, a silicon battery, and the like. Further, the “storage battery” here refers to, for example, a state in which a plurality of battery modules are housed in a case (hereinafter, referred to as a “battery pack”).

The vehicle lower structure according to the present invention according to claim 3 is arranged between the pair of rockers on the floor panel in the vehicle lower structure according to the present invention according to claim 1, and is arranged along the vehicle width direction. The floor cross member is bridged over the floor cross member, and the first shock absorbing portion is arranged at a position overlapping the floor cross member when viewed from the side of the vehicle.

In the vehicle lower structure according to the third aspect of the present invention, a floor cross member is bridged between a pair of rockers along the vehicle width direction on the floor panel, and the first impact absorbing portion is a vehicle side surface. It is arranged at a position where it visually overlaps with the floor cross member. As a result, at the time of a side collision of the vehicle, a part of the impact load input to the rocker is transmitted to the floor cross member side via the first impact absorbing unit.

When an impact load is input to the floor cross member, a reaction force is obtained from the floor cross member (strictly speaking, the rocker on the opposite side to the rocker to which the impact load is input via the floor cross member). As a result, the first impact absorbing portion is plastically deformed and the impact energy is absorbed.

The vehicle lower structure according to the present invention according to claim 4 is arranged between the pair of rockers on the floor panel in the vehicle lower structure according to the present invention according to claim 2, and is arranged along the vehicle width direction. The floor cross member is bridged and integrally formed with the outer portion and the inner portion, and the second shock absorbing portion is bridged between the outer portion and the inner portion in the vehicle width direction in the closed cross-sectional portion. The second shock absorbing portion is provided at a position overlapping the floor cross member when viewed from the side of the vehicle.

In the vehicle lower structure according to the fourth aspect of the present invention, a floor cross member is bridged between a pair of rockers along the vehicle width direction on the floor panel. On the other hand, a second shock absorbing portion is integrally formed together with the outer portion and the inner portion of the rocker. The second shock absorbing portion is bridged between the outer portion and the inner portion in the vehicle width direction in the closed cross-sectional portion of the rocker, and is provided at a position overlapping the floor cross member in the vehicle side view.

That is, the first shock absorbing portion and the second shock absorbing portion are bridged in the closed cross-sectional portion of the rocker in the vehicle width direction. The first shock absorbing portion and the second shock absorbing portion are integrally formed together with the outer portion and the inner portion, and the first shock absorbing portion is arranged at a position overlapping with the storage battery in the side view of the vehicle, and the second The shock absorbing portion is arranged at a position where it overlaps with the floor cross member when viewed from the side of the vehicle.

Therefore, at the time of a side collision of the vehicle, a part of the impact load input to the rocker is transmitted to the storage battery side via the first impact absorbing portion and the floor cross member side via the second impact absorbing portion. Will be transmitted to. When an impact load is input to the storage battery, a reaction force is obtained from the storage battery, and when an impact load is input to the floor cross member, the floor cross member (strictly speaking, the impact is passed through the floor cross member). The reaction force is obtained from the rocker on the opposite side of the rocker to which the load is input. As a result, the first impact absorbing portion and the second impact absorbing portion are plastically deformed, and the impact energy is absorbed.

Further, here, at the time of a side collision of the vehicle, the load is transmitted to the storage battery side via the first shock absorbing part of the rocker and to the floor cross member side via the second shock absorbing part of the rocker. It is possible to form a load transmission path. Therefore, it is possible to disperse the load with the impact load input to the rocker.

That is, in the present invention, the first shock absorbing portion and the second shock absorbing portion are provided in the closed cross-section portion of the rocker, and the first shock absorbing portion and the second shock absorbing portion are used as a storage battery and a floor cloth when viewed from the side of the vehicle. By arranging them so as to overlap each other and using the reaction force from the storage battery and the floor cross member, the inward bending of the rocker is suppressed.

As described above, the vehicle lower structure according to the first aspect of the present invention absorbs impact energy more effectively by suppressing the uncrushed residue of the first impact member, thereby preventing the rocker from bending inward. It has an excellent effect that it can be suppressed.

The vehicle lower structure according to the second aspect of the present invention has an excellent effect that it can obtain a reaction force from a storage battery to plastically deform the first impact member and absorb impact energy.

The vehicle lower structure according to the third aspect of the present invention has an excellent effect that a reaction force is obtained from a floor cross member to plastically deform the first impact member and absorb impact energy.

The vehicle lower structure according to the fourth aspect of the present invention obtains a reaction force from a storage battery and a reaction force from a floor cross member to plastically deform the first impact member and the second impact member to absorb impact energy. It has an excellent effect that it can be used.

It is a top view of the vehicle lower part to which the vehicle lower part structure which concerns on 1st Embodiment is applied. It is a cross-sectional view when cut along line 2-2 of FIG. (A) and (B) are schematic views showing a state in which an impact load is input to the rocker of the vehicle to which the vehicle lower structure according to the first embodiment is applied in chronological order. (C) and (D) are schematic views showing a state in which an impact load is input to the rocker of the vehicle to which the vehicle lower structure according to the first embodiment is applied in chronological order. (A) and (B) are comparative examples, and are schematic views showing a state in which an impact load is input to a vehicle rocker in chronological order. (C) and (D) are comparative examples, and are schematic views showing a state in which an impact load is input to the rocker of the vehicle in chronological order. It is sectional drawing corresponding to FIG. 2 which shows the modification of the vehicle lower structure which concerns on 1st Embodiment. It is sectional drawing corresponding to FIG. 2 which shows the vehicle lower structure which concerns on 2nd Embodiment. It is sectional drawing corresponding to FIG. 2 which shows the 1st modification of the vehicle lower structure which concerns on 2nd Embodiment. It is sectional drawing corresponding to FIG. 2 which shows the 2nd modification of the vehicle lower structure which concerns on 2nd Embodiment.

The vehicle lower structure according to the embodiment of the present invention will be described with reference to the drawings. The arrows FR, UP, and RH, which are appropriately described in the respective drawings, indicate the front direction, the upward direction, and the right direction of the vehicle to which the vehicle floor structure according to the embodiment of the present invention is applied, respectively. .. Hereinafter, when the description is simply made using the front-rear, up-down, and left-right directions, unless otherwise specified, the front-rear direction of the vehicle front-rear direction, the up-down direction of the vehicle up-down direction, and the left-right direction when facing the front direction are used.

<First Embodiment>
(Structure of vehicle substructure)

First, the configuration of the vehicle lower structure according to the present embodiment will be described. FIG. 1 shows a plan view of the vehicle lower portion 10 to which the vehicle lower structure according to the present embodiment is applied, and FIG. 2 shows a cross section when cut along line 2-2 in FIG. The figure is shown.

As shown in FIG. 1, a floor panel 12 extends in the vehicle lower portion 10 along the vehicle width direction and the vehicle front-rear direction. Bead portions 12A are intermittently projected from the floor panel 12 along the vehicle front-rear direction, and a plurality of bead portions 12A are arranged along the vehicle width direction. By forming the bead portion 12A, the rigidity of the floor panel 12 itself is improved.

Further, rockers 14 and 16 extend along the vehicle front-rear direction at both ends of the floor panel 12 in the vehicle width direction, and the vehicle is placed on the floor panel 12 between the rocker 14 and the rocker 16. Floor cross members (hereinafter, simply referred to as “cross members”) 18 are bridged along the width direction. The cross member 18 is arranged between the bead portion 12A and the bead portion 12A arranged along the vehicle front-rear direction.

Then, as shown in FIG. 2, a battery pack (rechargeable battery) 20 is arranged on the lower side of the floor panel 12 as a driving force supply device for supplying electric power to a power unit such as a motor.

As described above, rockers 14 and 16 extend along the front-rear direction of the vehicle at both ends of the floor panel 12 in the vehicle width direction. The rockers 14 and 16 will be described below. Since the rocker 16 has substantially the same configuration as the rocker 14, the description thereof will be omitted.

As shown in FIG. 2, in the present embodiment, the rocker 14 includes an outer portion 22 located outside in the vehicle width direction and an inner portion 24 located inside in the vehicle width direction. .. The rocker 14 is formed of, for example, a metal such as an aluminum alloy, and the outer portion 22 and the inner portion 24 are integrally formed by extrusion processing or drawing processing, and the outer portion 22 and the inner portion 24 form a closed cross-sectional portion. 26 is formed.

The outer portion 22 has an outer wall portion 22A formed along the vertical direction in a cross-sectional shape cut along the vehicle width direction, and is provided on the upper side of the outer wall portion 22A and upward as it goes inward in the vehicle width direction. It is configured to include an inclined upper wall portion 22B that inclines toward the side, and an inclined lower wall portion 22C that is provided on the lower side of the outer wall portion 22A and inclines downward toward the inside in the vehicle width direction. ing.

On the other hand, in the cross-sectional shape cut along the vehicle width direction, the inner portion 24 has an upper inner wall portion 24A formed along the vertical direction on the upper side of the inner portion 24 and the vehicle up and down on the lower side of the inner portion 24. It is configured to include a lower inner wall portion 24B formed along the direction. The lower inner wall portion 24B is located inside the upper inner wall portion 24A in the vehicle width direction, and a lateral wall portion formed along a substantially horizontal direction between the lower inner wall portion 24B and the upper inner wall portion 24A. 24C is provided. Therefore, the lateral wall portion 24C is formed so as to be connected to the lower inner wall portion 24B and the upper inner wall portion 24A.

Further, on the upper side of the upper inner wall portion 24A, an inclined upper wall portion 24D that inclines upward toward the outside in the vehicle width direction is provided, and the inclined upper wall portion 24D is the outer portion 22. It is formed so as to be connected to the inclined upper wall portion 22B. The flange portion 28 extends upward from the top portion 27 connecting the inclined upper wall portion 24D of the inner portion 24 and the inclined upper wall portion 22B of the outer portion 22. A lower end portion of a pillar (not shown) is connected to the flange portion 28.

Further, on the lower side of the lower inner wall portion 24B, a bottom wall portion 24E formed along a substantially horizontal direction toward the outside in the vehicle width direction is provided, and the bottom wall portion 24E is the outer portion 22. It is formed so as to be connected to the inclined lower wall portion 22C. The fastener 32 can be inserted into the bottom wall portion 24E, and the fixing piece 30 provided in the battery pack 20 can be fastened and fixed to the rocker 14 via the fastener 32.

As described above, the upper inner wall portion 24A of the inner portion 24 is located outside the lower inner wall portion 24B in the vehicle width direction. As a result, the area of the closed cross section differs between the upper portion 14A and the lower portion 14B of the rocker 14. That is, the area of the lower closed cross-section portion 34 provided on the lower 14B side of the rocker 14 is larger than the area of the upper closed cross-section portion 36 provided on the upper 14A side of the rocker 14. The rigidity of the lower 14B side of the rocker 14 is set to be higher than that of the upper 14A side.

A ladder-shaped shock absorbing portion (second shock absorbing portion) 38 is provided in the upper closed cross-section portion 36 of the rocker 14, and the shock absorbing portion 38 overlaps with the cross member 18 when viewed from the side of the vehicle. It is arranged like this. Further, a ladder-shaped shock absorbing portion (first shock absorbing portion) 40 is formed in the lower closed cross-section portion 34 of the rocker 14, and the shock absorbing portion 40 overlaps with the battery pack 20 when viewed from the side of the vehicle. It is arranged like this.

Here, the shock absorbing units 38 and 40 will be described, respectively.
The shock absorbing portions 38 and 40 are integrally formed together with the outer portion 22 and the inner portion 24. The shock absorbing portion 38 includes an upper wall 38A that is bridged between the upper inner wall portion 24A of the inner portion 24 and the outer wall portion 22A of the outer portion 22 along a substantially horizontal direction (vehicle width direction). .. A lower wall 38B is formed on the lower side of the upper wall 38A so as to face the upper wall 38A, and the lower wall 38B is connected to the side wall portion 24C to partition the upper 14A and the lower 14B of the rocker 14. ing. Further, between the upper wall 38A and the lower wall 38B, a plurality of (here, two) connecting walls 38C are bridged in the vertical direction.

On the other hand, the shock absorbing portion 40 includes an upper wall 40A bridged between the lower inner wall portion 24B of the inner portion 24 and the outer wall portion 22A of the outer portion 22 along a substantially horizontal direction (vehicle width direction). .. A lower wall 40B is formed on the lower side of the upper wall 40A so as to face the upper wall 40A, and a plurality of (here, three) connecting walls 40C are formed between the upper wall 40A and the lower wall 40B. It is laid up and down.

(Action and effect of vehicle substructure)
Next, the operation and effect of the vehicle lower structure according to the present embodiment will be described.

As shown in FIG. 2, in the present embodiment, in the rocker 14, the outer portion 22 and the inner portion 24 are integrally formed, and the outer portion 22 and the inner portion 24 form a closed cross-sectional portion 26. There is.

Thereby, for example, although not shown, the strength can be increased as compared with the case where the rocker is formed by connecting the two panels of the outer portion and the inner portion to each other. Further, when the rocker joins the two panels of the outer portion and the inner portion, welding or fastening is required. However, in the present embodiment, the outer portion 22 and the inner portion 24 are integrally formed. These processes are not required, and the cost can be reduced accordingly.

Further, in the present embodiment, in the upper portion 14A of the rocker 14 (inside the upper closed cross-section portion 36), the shock absorbing portion 38 is located between the outer portion 22 and the inner portion 24 at a position overlapping the cross member 18 in the vehicle side view. It is bridged in the width direction. Further, in the lower portion 14B of the rocker 14 (inside the lower closed cross-section portion 34), the shock absorbing portion 40 is bridged between the outer portion 22 and the inner portion 24 at a position overlapping the battery pack 20 in the vehicle side view in the vehicle width direction. Has been done.

Therefore, when the impact load F is input to the rocker 14 at the time of a side collision of the vehicle, a part of the impact load F is cross-membered via the impact absorbing portion 38 provided on the upper portion 14A side of the rocker 14. It is transmitted to the 18 side (transmission load F1) and is transmitted to the battery pack 20 side via the shock absorbing portion 40 provided on the lower 14B side of the rocker 14 (transmission load F2).

Then, when the impact load (transmission load F1) is transmitted to the cross member 18 via the impact absorbing unit 38, the impact load F is input to the cross member 18 (strictly speaking, through the cross member 18) in the rocker 14. The reaction force N1 is obtained from the rocker 16 (see FIG. 1) on the opposite side of the rocker 14. Further, when the impact load (transmission load F2) is transmitted to the battery pack 20 via the impact absorbing unit 40, the reaction force N2 is obtained from the battery pack 20 in the rocker 14. As a result, the shock absorbing portions 38 and 40 are plastically deformed, respectively, and the shock energy is absorbed.

Here, for example, as shown in FIGS. 5A and 5B and 6C and 6D, when the shock absorbing portion is provided as the shock absorbing member 100 separately from the rocker 102, for example, when the shock absorbing portion is provided separately from the rocker 102. When the shock absorbing member 100 is arranged in the closed cross-section portion 104 of the rocker 102, a rib 106 for movement regulation is provided in the closed cross section 104 so that the position of the shock absorbing member 100 does not shift due to an impact. There is a need.

In this way, when the rib 106 for movement regulation is provided in the closed cross-sectional portion 104 of the rocker 102, when the impact load F is input to the rocker 102 and the impact absorbing member 100 is plastically deformed, FIG. 6C is shown in FIG. , (D), the rib 106 may hinder the plastic deformation of the shock absorbing member 100.

In this way, when the plastic deformation of the shock absorbing member 100 is inhibited, so-called crushed residue is generated (crushed residue portion 108), and the amount of shock energy absorbed by the rocker 102 is reduced by the amount of the crushed residue. That is, there is a possibility that the impact energy cannot be absorbed efficiently.

On the other hand, in the present embodiment, as shown in FIGS. 3 (A) and 3 (B) and FIGS. 4 (C) and 4 (D), the shock absorbing portion 40 is integrated with the outer portion 22 and the inner portion 24. Since it is formed, it is not necessary to provide ribs or the like as shown in FIG. 5 (A). Therefore, in the present embodiment, as shown in FIGS. 4 (C) and 4 (D), it is possible to suppress the uncrushed residue of the shock absorbing unit 40.

That is, it is possible to effectively absorb the impact energy due to the collision load F, so that even if a large load is locally input to the rocker 14 as in the case of a pole side collision, the rocker 14 is internally bent. Can be suppressed. In other words, in the present embodiment, by suppressing the uncrushed residue of the shock absorbing unit 40, it is possible to more effectively absorb the shock energy and suppress the inward bending of the rocker 14.

In the present embodiment, as shown in FIG. 2, shock absorbing portions 38 and 40 are provided in the closed cross-sectional portion 26 of the rocker 14. On the other hand, in FIGS. 3 and 4, only the shock absorbing portion 40 is provided in the closed cross-sectional portion 26 of the rocker 14, but this is in accordance with the configurations of FIGS. 5 and 6 shown as comparative examples. Since the same can be said for the shock absorbing units 38 and 40 in the present embodiment, the illustration is omitted.

By the way, in the present embodiment shown in FIG. 2, as described above, when the impact load F is input to the rocker 14 at the time of a side collision of the vehicle, a part of the impact load F is a part of the upper portion 14A of the rocker 14. It is transmitted to the cross member 18 side via the shock absorbing portion 38 provided on the side (transmission load F1), and is transmitted to the battery pack 20 side via the shock absorbing portion 40 provided on the lower 14B side of the rocker 14. (Transmission load F2).

That is, here, the load transmission path A transmitted to the cross member 18 side via the shock absorbing portion 38 of the rocker 14 and the load transmission path transmitted to the battery pack 20 side via the shock absorbing portion 40 of the rocker 14. B and are formed. As a result, the impact load F input to the rocker 14 can be distributed, and the load load ratio can be changed between the upper portion 14A of the rocker 14 and the lower portion 14B of the rocker 14.

Therefore, the impact load F2 transmitted to the battery pack 20 side arranged on the lower side of the floor panel 12 can be reduced. According to this, for example, the rigidity of the battery pack 20 itself can be lowered by the amount that the impact load F2 transmitted to the battery pack 20 side is reduced. In this case, the thickness of the battery pack 20 can be reduced to reduce the weight of the battery pack 20. Further, the amount of the battery module 20A housed in the battery pack 20 can be increased by the amount that the plate thickness of the battery pack 20 is reduced.

(Supplementary matters of this embodiment)
In the present embodiment, the shock absorbing portion 38 and the shock absorbing portion 40 are each formed in a ladder shape, but the shapes of the shock absorbing portion 38 and the shock absorbing portion 40 are not limited to this. For example, the shape can be appropriately changed in relation to the plate thickness, such as thinning the plate thickness to form a honeycomb shape. Further, the plate thickness may be changed between the shock absorbing portion 38 and the shock absorbing portion 40, and the shock absorbing portion 38 and the shock absorbing portion 40 do not necessarily have the same shape.

Further, in the present embodiment, in the rocker 14, the shock absorbing portion 38 is provided at a position where it overlaps with the cross member 18 when viewed from the side of the vehicle, and the shock absorbing portion 40 is provided at a position where it overlaps with the battery pack 20 when viewed from the side of the vehicle. However, the embodiments applied in the present invention are not limited to this.

For example, as shown in FIG. 7, some vehicles do not have a cross member 18 (see FIG. 2) on the floor panel 12. In this case, the shock absorbing portion is not provided on the upper portion 42A side of the rocker 42 that overlaps with the cross member 18 (see FIG. 2) when viewed from the side of the vehicle. Therefore, the impact absorbing portion (first impact absorbing portion) 40 is provided on the lower portion 42B side of the rocker 42, but when the impact load F is input to the rocker 14 at the time of a side collision of the vehicle, the impact load F A part of the above is transmitted to the battery pack 20 side via the shock absorbing unit 40 (transmission load F3).

Then, when the impact load (transmission load F3) is transmitted to the battery pack 20 via the impact absorbing unit 40, the reaction force N3 is obtained from the battery pack 20 in the rocker 14. As a result, the shock absorbing portion 40 is plastically deformed, so that the shock energy is absorbed even in this case.

<Second Embodiment>
In the first embodiment, the case where the battery pack 20 (see FIG. 2) is used as the driving force supply device for supplying electric power to the power unit has been described, but in the present embodiment, as shown in FIG. A case where a hydrogen tank 44, which is a fuel cell, is used as a driving force supply device will be described. The description of substantially the same configuration as that of the first embodiment will be omitted. The embodiments applied in the present invention are not limited to this.

Here, in order to transmit the impact load input to the rocker to the floor cross member side arranged on the floor panel at the time of a side collision of the vehicle, a fuel cell is arranged on the lower side of the vehicle on the floor panel. In this case, it is preferable because the impact load can be prevented from being input to the fuel cell side.

As shown in FIG. 8, in the present embodiment, in the rocker 46, the shock absorbing portion 38 is provided at a position (upper 46A side of the rocker 46) that does not overlap with the hydrogen tank 44 when viewed from the side of the vehicle.

In this case, when the impact load F is input to the rocker 46 at the time of a side collision of the vehicle, a part of the impact load F is cross-membered via the impact absorbing portion 38 provided on the upper portion 46A side of the rocker 46. It is transmitted to the 18 side (transmission load F4). Then, when the impact load (transmission load F4) is transmitted to the cross member 18 via the impact absorbing unit 38, the rocker 46 obtains a reaction force N4 from the cross member 18. As a result, the shock absorbing portion 38 is plastically deformed and the shock energy is absorbed.

That is, it is possible to reduce the impact load F even with a short stroke, and it is possible to suppress the intrusion of the rocker 46 inward in the vehicle width direction. Then, in the present embodiment, it is possible to prevent the impact load F from being input to the hydrogen tank 44 side arranged on the lower side of the floor panel 12.

(Supplementary matters of this embodiment)
In the above embodiment, as shown in FIG. 1, the cross member 18 is bridged between the rockers 14 and 16, but for example, as shown in FIG. 9, when the hydrogen tank 47 has a large diameter. A hydrogen tank 47 may be arranged along the vehicle front-rear direction on the lower side of the tunnel portion 50 projecting from the floor panel 48 in the vehicle width direction in the vehicle front-rear direction.

In this case, the cross member 52 is bridged between a pair of rockers 54 arranged at both ends of the floor panel 48 in the vehicle width direction with the tunnel portion 50 in between. Here, the cross member 52 is formed along the shape of the tunnel portion 50, but the present invention is not limited to this.

For example, although not shown, two cross members may be provided along the vehicle width direction, which are divided by the tunnel portion. However, in this case, one end of the cross member in the longitudinal direction is connected to the rocker, and the other end of the cross member in the longitudinal direction is connected to the tunnel portion. Therefore, the impact load transmitted from the rocker to the cross member obtains a reaction force from the tunnel portion.

Further, in the above embodiment, the vehicle in which the battery pack 20 (see FIG. 2) and the hydrogen tank 44 (see FIG. 8) are used as the driving force supply device has been described, but this embodiment is for a gasoline vehicle. Is also applicable.

In the case of a gasoline-powered vehicle, for example, as shown in FIG. 10, since it is not necessary to dispose a driving force supply device on the lower side of the floor panel 56, the position of the floor panel 56 in the vertical direction is set low. be able to. Therefore, the shock absorbing portion (first shock absorbing portion) 60 provided so as to overlap the cross member 58 arranged on the floor panel 56 when viewed from the side of the vehicle is provided on the lower portion 62A side of the rocker 62. Become.

Although an example of the embodiment of the present invention has been described above, the embodiment of the present invention is not limited to the above, and one embodiment and various modifications may be used in combination as appropriate, and the present invention may be used. Of course, it can be carried out in various modes as long as it does not deviate from the gist of.

10 Vehicle lower part (vehicle lower structure)
12 Floor panel 14 Rocker 16 Rocker 18 Cross member (floor cross member)
20 Battery pack (storage battery)
22 Outer part (Rocka)
24 Inner part (Rocka)
26 Closed cross section 38 Shock absorbing part (1st shock absorbing part, 2nd shock absorbing part, rocker)
40 Shock absorber (1st shock absorber, rocker)
42 Rocker 46 Rocker 48 Floor Panel 52 Cross Member 54 Rocker 56 Floor Panel 58 Cross Member (Floor Cross Member)
60 Shock absorber (1st shock absorber)
62 Rocker

The vehicle lower structure according to the present invention according to claim 1 is arranged on both outer sides of the floor panel of the vehicle in the vehicle width direction, and a pair of rockers extending along the vehicle front-rear direction are formed in the vehicle width direction. An inner portion that is integrally formed with the outer portion and is located inside in the vehicle width direction and forms a closed cross section with the outer portion, and an inner portion that is integrally formed with the outer portion and the inner portion. A first shock absorbing portion formed and spanned in the vehicle width direction between the outer portion and the inner portion with gaps provided on the upper side and the lower side in the vehicle vertical direction in the closed cross-sectional portion is included. It is configured.

Further, in the closed cross-section of the rocker, the first shock absorbing portion is integrally formed together with the outer portion and the inner portion, and a gap is provided on the upper side and the lower side in the vertical direction of the vehicle in the closed cross-section portion between the outer portion and the inner portion. It is bridged in the width direction of the vehicle. Therefore, a part of the impact load input to the rocker at the time of a side collision of the vehicle (hereinafter referred to as "the side collision of the vehicle") is transmitted inward in the vehicle width direction via the first impact absorbing portion. It will be.

The vehicle lower structure according to the present invention according to claim 4 is arranged between the pair of rockers on the floor panel in the vehicle lower structure according to the present invention according to claim 2, and is arranged along the vehicle width direction. The floor cross member is bridged and integrally formed with the outer portion and the inner portion, and a gap is provided between the outer portion and the inner portion in the vertical direction of the vehicle in the closed cross-sectional portion. The second shock absorbing portion is bridged in the vehicle width direction, and the second shock absorbing portion is provided at a position where it overlaps with the floor cross member when viewed from the side of the vehicle.

In the vehicle lower structure according to the fourth aspect of the present invention, a floor cross member is bridged between a pair of rockers along the vehicle width direction on the floor panel. On the other hand, a second shock absorbing portion is integrally formed together with the outer portion and the inner portion of the rocker. This second shock absorbing portion is bridged between the outer portion and the inner portion in the vehicle width direction with gaps provided on the upper side and the lower side in the vertical direction of the vehicle in the closed cross section of the rocker, and is viewed from the side of the vehicle. It is installed at a position that overlaps with the floor cross member.

Claims (4)

A pair of rockers arranged on both outer sides of the floor panel of the vehicle in the vehicle width direction and extending along the vehicle front-rear direction
The outer part located on the outside in the vehicle width direction and
An inner portion that is integrally formed with the outer portion, is located inside in the vehicle width direction, and forms a closed cross-sectional portion with the outer portion.
A first shock absorbing portion integrally formed with the outer portion and the inner portion and bridged between the outer portion and the inner portion in the vehicle width direction in the closed cross-sectional portion.
Vehicle undercarriage constructed including. The vehicle lower structure according to claim 1, wherein a storage battery is arranged on the lower side of the floor panel of the vehicle, and the first shock absorbing portion is arranged at a position overlapping the storage battery when viewed from the side of the vehicle. On the floor panel, the floor cross members are arranged between the pair of rockers, the floor cross members are bridged along the vehicle width direction, and the first shock absorbing portion is arranged at a position overlapping the floor cross members in the vehicle side view. The vehicle lower structure according to claim 1. On the floor panel, the floor cross members are arranged between the pair of rockers, and the floor cross members are bridged along the vehicle width direction.
A second shock absorbing portion is integrally formed with the outer portion and the inner portion, and a second shock absorbing portion is bridged between the outer portion and the inner portion in the closed cross-sectional portion, and the second shock absorbing portion is a vehicle. The vehicle lower structure according to claim 2, which is provided at a position overlapping the floor cross member in a side view.

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