VEHICLE LOWER SECTION STRUCTURE

A vehicle lower section structure comprising a floor tunnel that extends along a vehicle front-rear direction at substantially a vehicle width direction center of a floor panel; protruding sections that are attached to the floor panel, that extend along the vehicle front-rear direction or the vehicle width direction, and that project out toward the vehicle lower side; a tank band fastened to the protruding sections; a tank that is retained by a tank band in a state in which an upper portion of the tank is housed inside the floor tunnel; and first shock absorbing sections that are provided between the respective protruding sections and a lower portion of the tank, and each of that is configured to alleviate impact force acting on the tank from any one of the protruding sections that is displaced in the vehicle width direction due to collision load from a vehicle side direction.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 USC 119 from Japanese Patent Application No. 2015-005205 filed Jan. 14, 2015, the disclosure of which is incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a vehicle lower section structure.

2. Related Art

Japanese Patent Application Laid-Open (JP-A) No. H04-368227 describes an invention relating to a tank mounting structure in an automobile equipped with a hydrogen engine. Specifically, a center tunnel that opens toward the vehicle lower side is formed at substantially a vehicle width direction center portion of a floor panel, and a tank that is capable of storing hydrogen gas extends along the center tunnel in a space at the vehicle lower side of the center tunnel. The tank is configured to have high rigidity, and so providing the high rigidity tank at the vehicle center portion improves the rigidity of the entire vehicle body.

However, in the configuration described in JP-A No. H04-368227, the tank is formed with an attachment flange that extends along the vehicle width direction from a tank outer peripheral face toward the tank outside. The attachment flange is bolt-fastened to a floor reinforcement attached to the floor panel, thereby attaching the tank to the floor panel, and accordingly to the vehicle. Thus, when collision load from the vehicle width direction outside is input along the vehicle width direction in a vehicle side face collision (such a collision state is referred to below as a vehicle side-on collision), the collision load is directly input to the tank from the floor reinforcement. The tank itself therefore needs to have a strong configuration so as to withstand the impact force, such that there is room for improvement of the above related art from the perspective of lightening the weight and reducing the cost of the tank.

SUMMARY

In consideration of the above circumstances, a subject of the present invention is to obtain a vehicle lower section structure capable of lightening the weight and reducing the cost of a tank.

A vehicle lower section structure of a first aspect of the present invention includes: a floor tunnel that extends along a vehicle front-rear direction at substantially a vehicle width direction center of a floor panel and that is open toward a vehicle lower side; protruding sections that are attached to the floor panel, that extend along the vehicle front-rear direction or the vehicle width direction, and that project out toward the vehicle lower side; a tank band fastened to the protruding sections; a tank that is retained by the tank band in a state in which an upper portion of the tank is housed inside the floor tunnel; and first shock absorbing sections that are provided between the respective protruding sections and a lower portion of the tank, and each of that is configured to alleviate impact force acting on the tank from any one of the protruding sections that is displaced in the vehicle width direction due to collision load from a vehicle side direction.

A vehicle lower section structure of a second aspect of the present invention is the vehicle lower section structure of the first aspect, wherein each of the first shock absorbing sections is provided with a shock absorbing member that absorbs the impact force.

A vehicle lower section structure of a third aspect of the present invention is the vehicle lower section structure of the first aspect or the second aspect, wherein: the tank band is configured divided into one band and another band; and one end portion of each of the bands is fastened to one of the protruding section, and the one band and the other band are installed separated from each other.

A vehicle lower section structure of a fourth aspect of the present invention includes: a floor tunnel that extends along a vehicle front-rear direction at substantially a vehicle width direction center of a floor panel and that is open toward a vehicle lower side; protruding sections that are attached to the floor panel, that extend along the vehicle front-rear direction or the vehicle width direction, and that project out toward the vehicle lower side; a tank band fastened to the protruding sections; a tank that is retained by the tank band in a state in which an upper portion of the tank is housed inside the floor tunnel; and a second shock absorbing section that is formed to a portion of the tank band, and that is configured to alleviate impact force acting on the tank from any one of the protruding section that is displaced in the vehicle width direction due to collision load from a vehicle side direction.

A vehicle lower section structure of a fifth aspect of the present invention is the vehicle lower section structure of any one of the first aspect to the fourth aspect, wherein the tank band is provided with a tank support portion that abuts the tank and that is formed in substantially the same shape as an outside face of the tank at the abutted location.

A vehicle lower section structure of a sixth aspect of the present invention is the vehicle lower section structure of any one of the first aspect to the fifth aspect, wherein a tank protection plate formed in a plate shape is provided at the vehicle lower side of the tank and the tank band so as to cover the tank from at least the vehicle lower side.

A vehicle lower section structure of a seventh aspect of the present invention is the vehicle lower section structure of the sixth aspect, wherein the tank protection plate is configured by an inner panel that supports the tank, and an outer panel that is disposed separated from the inner panel at the vehicle lower side of the inner panel.

A vehicle lower section structure of an eighth aspect of the present invention is the vehicle lower section structure of any one of the first aspect to the fourth aspect, further including a tank support member that is provided between the tank band and the tank, wherein the tank support member is formed with a tank support portion that abuts the tank and is formed in substantially the same shape as an outside face of the tank at the abutted location.

In the first aspect, the first shock absorbing sections are provided between the tank housed inside the floor tunnel and the protruding sections attached to the floor panel. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel, the floor panel and the protruding section attached to the floor panel are displaced along the vehicle width direction and abut the tank. Impact force from the protruding section thereby acts on the tank. However, in the present aspect, the impact force acting on the tank from the protruding section can be alleviated by the first shock absorbing section. This enables an impact resistant structure of the tank to have a simple structure.

In the second aspect, the shock absorbing member is provided at each of the first shock absorbing sections, thereby enabling impact force acting on the tank from the protruding section in a vehicle side-on collision to be further alleviated. This enables the impact resistant structure of the tank to be improved.

In the third aspect, the tank band is configured by the one band and the other band, and the one band and the other band are separated from each other. This enables variations in dimensions and variations in assembly of the tank band and the floor panel, etc. to be adjustable in this separated space.

In the fourth aspect, the second shock absorbing section formed at the tank band is included in a range between each of the protruding sections attached to the floor panel and the tank. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel, the floor panel and the protruding section attached to the floor panel are displaced along the vehicle width direction. Impact force from the protruding section thereby acts on the tank. However, in the present aspect, the impact force acting on the tank from the protruding section can be alleviated by the second shock absorbing section. This enables the impact resistant structure of the tank to have a simple structure.

In the fifth aspect, the tank support portion that is formed in substantially the same shape as the outside face of the tank supports the tank, such that the tank and the tank support portion are in constant contact with each other. This enables the tank to be retained in a specific position, and enables the tank to be stably supported, thereby enabling the tank to be suppressed from vibrating. This enables impact force acting on the tank due to vibration to be alleviated, thereby enabling the impact resistant structure of the tank to be improved.

In the sixth aspect, the tank is covered from the vehicle lower side by the tank protection plate, such that impact force input to the vehicle from the vehicle lower side by an obstacle or the like is input to the tank protection plate. Namely, the impact force from the vehicle lower side is less liable to be directly transmitted to the tank, and can be alleviated by the tank protection plate.

In the seventh aspect, a region surrounded by the inner panel and the outer panel can be configured as a deformation absorption section. Thus, even if the tank protection plate deforms so as to project out toward the vehicle upper side due to impact force input to the vehicle from the vehicle lower side by an obstacle or the like, the tank protection plate and the tank are suppressed from abutting each other by the deformation absorption section, thereby enabling the impact force acting on the tank from the tank protection plate to be alleviated.

In the eighth aspect, the tank support member is provided between the tank band and the tank, and the tank support portion that is formed in substantially the same shape as the outside face of the tank is formed at the tank support member and supports the tank. Thus the tank and the tank support portion are in constant contact. This enables the tank to be retained in a specific position, and enables the tank to be stably supported, thereby enabling the tank to be suppressed from vibrating. This enables impact force acting on the tank due to vibration to be alleviated, thereby enabling the impact resistant structure of the tank to be improved.

The vehicle lower section structure of the first aspect, second aspect, and fourth to eighth aspects has excellent advantageous effects of enabling the tank to have a lighter weight and a lower cost.

The vehicle lower section structure of the third aspect has an excellent advantageous effect of enabling assembly performance of the tank to the floor panel to be improved.

DETAILED DESCRIPTION OF THE INVENTION

First Exemplary Embodiment

Explanation follows regarding a first exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 1toFIG. 2B. Note that in the drawings, the arrow FR indicates the vehicle front-rear direction front side, the arrow OUT indicates the vehicle width direction outside, and the arrow UP indicates the vehicle up-down direction upper side, respectively.

As illustrated inFIG. 1, a floor tunnel14is formed at substantially the vehicle width direction center of a floor panel12configuring a lower section of a vehicle10. The floor tunnel14is formed with a cross-section profile orthogonal to the vehicle front-rear direction in an inverted U-shape, and with an opening16at the vehicle lower side. The floor tunnel14extends along the vehicle front-rear direction from a dash panel18provided at a front end of the floor panel12across to a rear end portion of the floor panel12. Note that, although the floor tunnel14is formed at substantially the vehicle width direction center of the floor panel12in the present exemplary embodiment, the floor tunnel14may be formed at a position that is slightly offset from the vehicle width direction center.

A hydrogen tank20, serving as a tank, is housed inside the floor tunnel14at the vehicle lower side of the floor tunnel14(seeFIG. 3). The hydrogen tank20is formed in a substantially circular tube shape with its axis along the vehicle front-rear direction, and both vehicle front-rear direction ends are closed off by end portions, each formed in a substantially semi-spherical shape. The interior of the hydrogen tank20is thereby configured as a sealed structure capable of being filled with hydrogen. The hydrogen tank20is supported from the vehicle lower side by plural tank bands24provided at the vehicle lower side of the hydrogen tank20. Each tank band24is formed in a substantially rectangular shape in plan view, and has both length direction end portions fastened to the floor panel12side by bolts22(seeFIGS. 3), or the like.

A portion of the hydrogen tank20excluding a lower portion is housed inside the floor tunnel14. As illustrated inFIG. 2B, a vehicle up-down direction center C1of the hydrogen tank20is disposed further to the upper side than reinforcement bottom wall portions38of floor reinforcements26, described later, that is joined to the floor panel12. The vehicle up-down direction height of the hydrogen tank20is set at a specific height so as to avoid interference with obstacles or the like on a road surface R. Namely, the floor is set taking a space for the hydrogen tank20into consideration. Thus, in the present exemplary embodiment, a vehicle up-down direction height dimension of the floor tunnel14is increased, and a vehicle lower side face of the floor panel12is disposed further to the vehicle lower side than a configuration in which the vehicle up-down direction center of the hydrogen tank20is disposed further to the lower side than the reinforcement bottom wall portions38of the floor reinforcements26, as illustrated inFIG. 2A. A space28inside a vehicle cabin is thereby enlarged. Moreover, side wall portions30of the floor tunnel14are disposed at the vehicle width direction outside of the hydrogen tank20, such that a range over which the hydrogen tank20is covered by the floor tunnel14is increased, thereby enabling impact force acting on the hydrogen tank20in a vehicle side-on collision to be alleviated. Furthermore, by increasing the vehicle up-down direction height dimension of the floor tunnel14, the rigidity of the floor tunnel14is improved, and collision load acting on the floor panel12in a vehicle head-on collision is concentrated at the floor tunnel14. This alleviates the input of collision load to the hydrogen tank20.

As illustrated inFIG. 3A, each floor reinforcement26, serving as a protruding section, is joined to an end portion of the opening16of the floor tunnel14, namely, in the vicinity of a joint portion between a vehicle lower side end portion32of the floor tunnel14and a lower wall portion34of the floor panel12. A cross-section of the floor reinforcement26orthogonal to the vehicle front-rear direction is formed in a substantially U-shape, including a pair of reinforcement upright wall portions36extending substantially along the vehicle up-down direction, and the reinforcement bottom wall portion38that links between respective vehicle lower side end portions of the reinforcement upright wall portions36. The floor reinforcement26extends substantially in the vehicle front-rear direction along the floor tunnel14. Flange portions40, which each extend along the vehicle width direction in directions moving away from each other, are provided at vehicle upper side end portions of the respective reinforcement upright wall portions36, and the flange portions40are joined to the floor panel12. The floor reinforcement26is thereby joined to the floor panel12.

The reinforcement bottom wall portion38of the floor reinforcement26is formed with a reinforcement fastening hole39piercing through in the plate thickness direction. The bolt22is inserted through the reinforcement fastening hole39and a band cross fastening hole41formed piercing through each end portion of the tank bands24in the plate thickness direction, and the bolt22is fastened to a nut42. The tank bands24are thereby fastened to the floor panel12via the floor reinforcements26. Note that in each tank band24, a tank abutting portion44that abuts the vehicle lower side of the hydrogen tank20and serves as a tank support portion has substantially the same shape as the shape at an abutted portion of an outer peripheral face of the hydrogen tank20.

A first shock absorbing section46is provided between the reinforcement upright wall portion36at the vehicle inside of the floor reinforcement26at a location at which the tank bands24are provided, and an outside face of the hydrogen tank20. In the present exemplary embodiment, a shock absorbing member48is provided at the first shock absorbing section46. The shock absorbing member48is a rubber block, and is attached to the reinforcement upright wall portion36at the vehicle inside of the floor reinforcement26. Note that the shock absorbing member48is provided at the vehicle upper side of the tank bands24, thereby suppressing the shock absorbing members48from falling toward the vehicle lower side. In the present exemplary embodiment, each shock absorbing member48is a rubber block; however, configuration is not limited thereto, and the shock absorbing member48may be configured of another material such as aluminum alloy, and may have a mesh structure or a honeycomb structure.

As illustrated inFIG. 3B, in cases in which the tank band24is attached at a location where floor cross members50, serving as a protruding section, are provided, the tank band24is fastened to the floor cross members50. Specifically, a cross-section profile of each floor cross member50orthogonal to the vehicle front-rear direction is formed in substantially an L-shape, by a member upright wall portion52, and a member bottom wall portion54extending along the vehicle width direction from a vehicle lower side end portion of the member upright wall portion52. A vehicle width direction outside end portion of the member bottom wall portion54is joined by welding to the reinforcement bottom wall portion38of the floor reinforcement26from the vehicle lower side, and a vehicle upper side end portion of the member upright wall portion52is joined to the end portion of the opening16of the floor tunnel14. The floor cross member50is thereby joined to the floor panel12.

The member bottom wall portion54of the floor cross member50is formed with a member fastening hole55formed piercing through in the plate thickness direction. The bolt22is inserted through the member fastening hole55and the band cross fastening hole41piercing through either end of the tank band24in the plate thickness direction, and the bolt22is fastened by the nut42, thereby fastening the tank band24to the floor panel12via the floor cross member50.

The first shock absorbing section46is provided between the member upright wall portion52at the vehicle inside of the floor cross member50at the location at which the tank band24is provided, and the outside face of the hydrogen tank20. The first shock absorbing section46is provided with the shock absorbing member48, similarly to as previously described. The shock absorbing member48is provided at the vehicle upper side of the tank band24, thereby suppressing the shock absorbing member48from falling toward the vehicle lower side.

Note that the floor cross member50described above is configured joined to the floor reinforcement26; however configuration is not limited thereto, and as illustrated inFIG. 4, the floor cross member50may be only joined to the floor panel12. In such cases, the tank band24is fastened to the floor panel12via floor cross members51, each serving as a protruding section.

Although not'illustrated in the drawings, when assembling the hydrogen tank20to the floor panel12, both the tank bands24and the hydrogen tank20are lifted toward the vehicle upper side in a state abutting each other, and the hydrogen tank20is housed inside the floor tunnel14of the floor panel12from the vehicle lower side of the floor panel12. The tank bands24and the floor reinforcements26(floor cross members50,51) are then fastened together by the bolts22, thereby enabling the hydrogen tank20and the tank bands24to be attached to the vehicle10at the same time.

Operation and Advantageous Effects of First Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the first exemplary embodiment.

As illustrated inFIG. 3A,FIG. 3B, in the present exemplary embodiment, each first shock absorbing section46is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor reinforcement26or the floor cross member50,51(seeFIG. 4) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor reinforcement26or the floor cross member50,51attached to the floor panel12is displaced along the vehicle width direction and abuts the hydrogen tank20. Impact force from the floor reinforcement26or the floor cross member50,51thereby acts on the hydrogen tank20. However, in the present embodiment, the floor reinforcement26or the floor cross member50,51is separated from the hydrogen tank20by the first shock absorbing section46, thereby enabling impact force acting on the hydrogen tank20from the floor reinforcement26or the floor cross member50,51to be alleviated. This enables an impact resistant structure of the hydrogen tank20to be provided by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

Since the shock absorbing member48is provided at the first shock absorbing section46, impact force acting on the hydrogen tank20from the floor reinforcement26or the floor cross member50,51in a vehicle side-on collision can be further alleviated. This enables the impact resistant structure of the hydrogen tank20to be further improved.

The respective vehicle width direction end portions of the tank bands24are fastened to a floor reinforcement26or the floor cross member50,51in the vehicle width direction one side, and to the other floor reinforcement26or the floor cross member50,51provided at the opposite side in the vehicle width direction, with the hydrogen tank interposed therebetween. Thus, when collision load along the vehicle width direction is input to the floor panel12from the vehicle width direction outside in a vehicle side-on collision, collision load is transmitted from one floor reinforcement26or floor cross member50,51to the other floor reinforcement26or floor cross member50,51through the tank bands24. This enables collision load acting directly on the hydrogen tank20to be reduced.

Since the tank abutting portions44that are formed in the same shape as an abutted portion of the outside face of the hydrogen tank20support the hydrogen tank20, the hydrogen tank20and the tank abutting portions44are in constant contact with each other. This enables the hydrogen tank20to be retained in a specific position, and enables the hydrogen tank20to be stably supported, thereby enabling the hydrogen tank20to be suppressed from vibrating. This enables impact force acting on the hydrogen tank20due to vibration to be alleviated, thereby enabling the impact resistant structure of the hydrogen tank20to be further improved by a simple structure.

Second Exemplary Embodiment

Explanation follows regarding a second exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 5. Note that similar configuration portions to the first exemplary embodiment, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the second exemplary embodiment has the same basic configuration as the first exemplary embodiment, with a feature that each tank band58is configured as a divided structure.

Namely, the tank band58is configured by a first band60serving as one band, and a second band62serving as another band. Note that the first band60and the second band62are structures with left-right symmetry along the vehicle width direction about substantially the vehicle width direction center, and so only the one first band60is explained with reference to the drawings below.

The first band60is configured including a fastening wall portion64extending along the vehicle width direction, a tank support wall portion66provided at the vehicle lower side of the fastening wall portion64, and a coupling wall portion68that couples between the fastening wall portion64and the tank support wall portion66. The fastening wall portion64abuts the reinforcement bottom wall portion38of the floor reinforcement26from the vehicle lower side. The fastening wall portion64is formed with a reinforcement fastening hole65piercing through in the plate thickness direction at a position corresponding to the reinforcement fastening hole39formed at the reinforcement bottom wall portion38. The bolt22is inserted through the reinforcement fastening hole39and the reinforcement fastening hole65and fastened by the nut42, such that the fastening wall portion64, and accordingly the first band60, is fastened to the floor panel12via the floor reinforcement26.

A vehicle width direction inside end portion of the fastening wall portion64extends toward the vehicle width direction inside as far as substantially the same position as a vehicle width direction inside end portion of the shock absorbing member48attached to the floor reinforcement26. Namely, configuration is such that the fastening wall portion64is capable of supporting the shock absorbing member48from the vehicle lower side. The shock absorbing member48is thereby suppressed from falling toward the vehicle lower side.

The coupling wall portion68extends toward the vehicle lower side from the vehicle width direction inside end portion of the fastening wall portion64. The tank support wall portion66extends along the vehicle width direction toward the vehicle width direction inside from a vehicle lower side end portion of the coupling wall portion68. The tank support wall portion66abuts the vehicle lower side of the hydrogen tank20, and a vehicle width direction inside end portion of the tank support wall portion66is configured so as to be positioned further to the vehicle width direction outside than a vehicle width direction center C2of the hydrogen tank20. The first band60and the second band62are thereby attached to the floor reinforcements26in a separated state.

Operation and Advantageous Effects of Second Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the second exemplary embodiment.

As illustrated inFIG. 5, similarly to in the first exemplary embodiment, in the present exemplary embodiment, each first shock absorbing section46is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor reinforcement26(floor cross member50,51) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor reinforcement26(floor cross member50,51) attached to the floor panel12are displaced along the vehicle width direction and abut the hydrogen tank20. Impact force from the floor reinforcement26or the floor cross member50,51thereby acts on the hydrogen tank20. However, in the present embodiment, the floor reinforcement26(floor cross member50,51) is separated from the hydrogen tank20by the first shock absorbing section46, thereby enabling impact force acting on the hydrogen tank20from the floor reinforcement26(floor cross member50,51) to be alleviated. This enables the impact resistant structure of the hydrogen tank20to be provided by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

Since the shock absorbing member48is provided at the first shock absorbing section46, impact force acting on the hydrogen tank20from the floor reinforcement26or the floor cross member50,51in a vehicle side-on collision can be further alleviated. This enables the impact resistant structure of the hydrogen tank20to be further improved.

The tank band58is configured such that the first band60and the second band62are separated from each other, thereby enabling variations in dimensions and variations in assembly of the tank band58and the floor panel12, etc. to be adjustable. This facilitates attachment of the tank band58to the vehicle10, enabling ease of assembly to be improved.

Third Exemplary Embodiment

Explanation follows regarding a third exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 6. Note that similar configuration portions to the first and second exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the third exemplary embodiment has the same basic configuration as the second exemplary embodiment, with a feature that a first band72and a second band74of a tank band70are each configured by the fastening wall portion64, and a tank support wall portion76serving as a tank support portion. Note that the first band72and the second band74are structures with left-right symmetry along the vehicle width direction about substantially the vehicle width direction center, and so only the one first band72is explained with reference to the drawings below.

The first band72is configured including the fastening wall portion64, and the tank support wall portion76provided at the vehicle width direction inside end portion of the fastening wall portion64. The fastening wall portion64extends along the vehicle width direction as far as a position where the vehicle width direction inside end portion thereof abuts the hydrogen tank20. The tank support wall portion76is formed in substantially the same shape as the shape of an abutted portion of the outer peripheral face of the hydrogen tank20.

Operation and Advantageous Effects of Third Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the third exemplary embodiment.

As illustrated inFIG. 6, similarly to in the first and second exemplary embodiments, in the present exemplary embodiment, each first shock absorbing section46is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor reinforcement26(floor cross member50,51) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor reinforcement26(the floor cross member50,51) attached to the floor panel12are displaced along the vehicle width direction and abut the hydrogen tank20. Impact force from the floor reinforcement26or the floor cross member50,51thereby acts on the hydrogen tank20. However, in the present embodiment, the floor reinforcement26(floor cross member50,51) is separated from the hydrogen tank20by the first shock absorbing section46, thereby enabling impact force acting on the hydrogen tank20from the floor reinforcement26or the floor cross member50,51to be alleviated. This enables the impact resistant structure of the hydrogen tank20to be provided by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

Since the shock absorbing member48is provided at the first shock absorbing section46, impact force acting on the hydrogen tank20from the floor reinforcement26or the floor cross member50,51in a vehicle side-on collision can be further alleviated. This enables the impact resistant structure of the hydrogen tank20to be further improved.

Since the tank support wall portions76of the first band72and the second band74are formed in the same shape as abutted portions of the outside face of the hydrogen tank20and support the hydrogen tank20, the hydrogen tank20and the tank support wall portions76are in constant contact with each other. This enables the hydrogen tank20to be retained in a specific position, and enables the hydrogen tank20to be stably supported, thereby enabling the hydrogen tank20to be suppressed from vibrating. This enables impact force acting on the hydrogen tank20due to vibration to be alleviated, thereby enabling the impact resistant structure of the hydrogen tank20to be improved by a simple structure.

Fourth Exemplary Embodiment

Explanation follows regarding a fourth exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIGS. 7A and 7B. Note that similar configuration portions to the first to third exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the fourth exemplary embodiment has the same basic configuration as the second exemplary embodiment, with a feature that tank abutting members80are provided at tank bands78.

As illustrated inFIG. 7A, the tank band78is configured by a first band82and a second band84. Note that the first band82and the second band84are structures with left-right symmetry along the vehicle width direction about substantially the vehicle width direction center, and so only the one first band82is explained with reference to the drawings below.

The first band82is configured including the fastening wall portion64, a tank support wall portion86provided at the vehicle lower side of the fastening wall portion64, and the coupling wall portion68that couples between the fastening wall portion64and the tank support wall portion86.

The coupling wall portion68extends toward the vehicle lower side from the vehicle width direction inside end portion of the fastening wall portion64. The tank support wall portion86extends along the vehicle width direction toward the vehicle width direction inside from a vehicle lower side end portion of the coupling wall portion68. The tank support wall portion86is separated from the vehicle lower side of the hydrogen tank20, and a vehicle width direction inside end portion of the tank support wall portion86is configured so as to be positioned further to the vehicle width direction outside than the vehicle width direction center C2of the hydrogen tank20.

The tank abutting member80is attached to a vehicle upper side face of the tank support wall portion86. A cross-section profile of the tank abutting member80orthogonal to the vehicle front-rear direction is formed in a substantially rectangular shape, with an upper wall portion90, an inside wall portion92, a tank abutting portion94serving as a tank support portion, a bottom wall portion96, and an outside wall portion98.

The tank abutting portion94is provided between the upper wall portion90provided at the vehicle upper side, and the inside wall portion92provided at the vehicle width direction inside. The tank abutting portion94abuts the hydrogen tank20and is formed in substantially the same shape as an abutted portion of the outer peripheral face of the hydrogen tank20. The outside wall portion98provided at the vehicle width direction outside abuts the coupling wall portion68, and the bottom wall portion96provided at the vehicle lower side abuts the tank support wall portion86. As illustrated inFIG. 7B, the tank abutting member80is provided with attachment tabs100, each formed in a plate shape. A bolt104is inserted through a tab fastening hole102piercing through each attachment tab100in the plate thickness direction, and a support wall portion fastening hole, not illustrated in the drawings, piercing through the tank support wall portion86in the plate thickness direction at a position corresponding to the tab fastening hole102, and the bolt104is fastened by a nut, not illustrated in the drawings. The tank abutting member80is thereby fixed to the tank support wall portion86. Note that in the present exemplary embodiment, the tank abutting member80is configured as a structure fastened by the bolts104; however, configuration is not limited thereto, and a structure may be configured such that the tank abutting member80is attached to the tank support wall portion86by structural adhesive or the like.

In the present exemplary embodiment, the tank abutting members80are provided at the tank band78configured as divided structure; however, configuration is not limited thereto, and as illustrated inFIG. 8A, the tank abutting members80may be provided at a tank band106configured as a single member. In the present exemplary embodiment, configuration is such that one each of tank abutting members80are provided so as to have left-right symmetry to each other; however, configuration is not limited thereto, and as illustrated inFIG. 8B, a tank abutting member130may be configured as a single member. The tank abutting member130is formed by upper wall portions200, a tank abutting portion204serving as a tank support portion, a bottom wall portion206, and outside wall portions208. The tank abutting portion204abuts the hydrogen tank20and is formed in substantially the same shape as an abutted portion of the outer peripheral face of the hydrogen tank20

Operation and Advantageous Effects of Fourth Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the fourth exemplary embodiment.

As illustrated inFIG. 7A, similarly to in the first to third exemplary embodiments, in the present exemplary embodiment, each first shock absorbing section46is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor reinforcement26(floor cross member50,51) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor reinforcement26(the floor cross member50,51) attached to the floor panel12are displaced along the vehicle width direction and abut the hydrogen tank20. Impact force from the floor reinforcement26or the floor cross member50,51thereby acts on the hydrogen tank20. However, in the present embodiment, the floor reinforcement26(floor cross member50,51) is separated from the hydrogen tank20by the first shock absorbing section46, thereby enabling impact force acting on the hydrogen tank20from the floor reinforcement26(floor cross member50,51) to be alleviated. This enables the impact resistant structure of the hydrogen tank20to be provided by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

Since the shock absorbing member48is provided at the first shock absorbing section46, impact force acting on the hydrogen tank20from the floor reinforcement26(floor cross member50,51) in a vehicle side-on collision can be further alleviated. This enables the impact resistant structure of the hydrogen tank20to be further improved.

Since the tank abutting portions94,204of the tank abutting members80,130that are formed in the same shape as an abutted portion of the outside face of the hydrogen tank20support the hydrogen tank20, the hydrogen tank20and the tank abutting portions94,204are in constant contact with each other. This enables the hydrogen tank20to be retained in a specific position, and enables the hydrogen tank20to be stably supported, thereby enabling the hydrogen tank20to be suppressed from vibrating. This enables impact force acting on the hydrogen tank20due to vibration to be alleviated, thereby enabling the impact resistant structure of the hydrogen tank20to be further improved by a simple structure.

Fifth Exemplary Embodiment

Explanation follows regarding a fifth exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 9AandFIG. 9B. Note that similar configuration portions to the first to fourth exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the fifth exemplary embodiment has the same basic configuration as the first exemplary embodiment, with a feature that second shock absorbing sections110are provided at a tank band108.

Namely, as illustrated inFIG. 9A, the tank band108is configured including fastening wall portions112, a tank abutting portion144provided at the vehicle inside of the fastening wall portions112, and the second shock absorbing sections110that couple between the fastening wall portions112and the tank abutting portion144. Each fastening wall portion112abuts the reinforcement bottom wall portion38of the floor reinforcement26from the vehicle lower side. The fastening wall portion112is formed with a band cross fastening hole113piercing through in the plate thickness direction at a position corresponding to the reinforcement fastening hole39formed at the reinforcement bottom wall portion38. The bolt22is inserted through the reinforcement fastening hole39and the band cross fastening hole113and fastened by the nut42, such that the fastening wall portion112, and accordingly the tank band108, is fastened to the floor panel12via the floor reinforcement26.

The tank abutting portion144abuts the vehicle lower side of the hydrogen tank20and is formed in substantially the same shape as an abutted portion of the outer peripheral face of the hydrogen tank20. Each second shock absorbing section110is formed with a stretching and contracting portion116that is bent so as to form undulations substantially along the vehicle up-down direction. The fastening wall portion112is capable of displacement relative to the tank abutting portion114due to the stretching and contracting portion116. Note that the second shock absorbing section110is not limited to a configuration that is bent so as to form undulations substantially along the vehicle up-down direction as illustrated inFIG. 9A,FIG. 9B, andFIG. 10A, and may be configured formed with a stretching and contracting portion117that is bent so as to form undulations along the vehicle width direction, as illustrated inFIG. 10B.

As illustrated inFIG. 9B, at a location where the floor cross members50are provided, the bolt22is inserted through the band cross fastening hole113provided piercing through either end portion of the tank band108in the plate thickness direction and the member fastening hole55of each floor cross member50, and the bolt22is fastened by the nut42, thereby fastening the tank band108to the floor panel12via the floor cross member50.

Operation and Advantageous Effects of Fifth Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the fifth exemplary embodiment.

As illustrated inFIG. 9AandFIG. 9B, in the present exemplary embodiment, each second shock absorbing section110is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor reinforcement26(floor cross member50,51) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor reinforcement26(the floor cross member50,51) attached to the floor panel12are displaced along the vehicle width direction and abut the hydrogen tank20. Impact force from the floor reinforcement26or the floor cross member50,51thereby acts on the hydrogen tank20. However, the present embodiment enables the impact force acting on the hydrogen tank20from the floor reinforcement26(floor cross member50,51) to be alleviated by the second shock absorbing section110. This enables the impact resistant structure of the hydrogen tank20to be formed by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

Since the tank abutting portion144that is formed in the same shape as an abutted portion of the outside face of the hydrogen tank20supports the hydrogen tank20, the hydrogen tank20and the tank abutting portion144are in constant contact with each other.

This enables the hydrogen tank20to be retained in a specific position, and enables the hydrogen tank20to be stably supported, thereby enabling the hydrogen tank20to be suppressed from vibrating. This enables impact force acting on the hydrogen tank20due to vibration to be alleviated, thereby enabling the impact resistant structure of the hydrogen tank20to be improved by a simple structure.

Sixth Exemplary Embodiment

Explanation follows regarding a sixth exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 11AandFIG. 11B. Note that similar configuration portions to the first to fifth exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the sixth exemplary embodiment has the same basic configuration as the fifth exemplary embodiment, with a feature that tank abutting members80are provided at a tank band118.

Namely, as illustrated inFIG. 11A, the tank band118is configured including the fastening wall portions112, a tank support wall portion120provided at the vehicle inside of the fastening wall portions112, and the second shock absorbing sections110that couple the fastening wall portions112and the tank support wall portion120together. A cross-section profile of the tank support wall portion120orthogonal to the vehicle front-rear direction is formed in a substantially U-shape, by a pair of side wall portions126, and a bottom wall portion128that couples together respective vehicle lower side end portions of the side wall portions126. The tank support wall portion120is disposed at a position that is separated from the hydrogen tank20at the vehicle lower side thereof.

Two of the tank abutting members80are attached to the tank support wall portion120. Namely, in one tank abutting member80, the outside wall portion98abuts one side wall portion126, and the bottom wall portion96abuts the bottom wall portion128and is attached to the tank support wall portion120. Similarly, in the other tank abutting member80, the outside wall portion98abuts the other side wall portion126, and the bottom wall portion96abuts the bottom wall portion128and is attached to the tank support wall portion120. Namely, the one tank abutting member80and the other tank abutting member80are disposed with left-right symmetry about the vehicle width direction center of the hydrogen tank20.

Note that in the present exemplary embodiment, configuration is such that one each of tank abutting members80are provided so as to have left-right symmetry to each other; however, configuration is not limited thereto, and as illustrated inFIG. 11B, the tank abutting member130may be configured as a single member.

Operation and Advantageous Effects of Sixth Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the sixth exemplary embodiment.

As illustrated inFIG. 11AandFIG. 11B, in the present exemplary embodiment, similarly to in the fifth exemplary embodiment, each second shock absorbing section110is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor reinforcement26(floor cross member50,51) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor reinforcement26(the floor cross member50,51) attached to the floor panel12are displaced along the vehicle width direction and abut the hydrogen tank20. Impact force from the floor reinforcement26or the floor cross member50,51thereby acts on the hydrogen tank20. However, the present embodiment enables the impact force acting on the hydrogen tank20from the floor reinforcement26(floor cross member50,51) to be alleviated by the second shock absorbing section110. This enables the impact resistant structure of the hydrogen tank20to be formed by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

Since the tank abutting portions94,204of the tank abutting members80,130that are formed in the same shape as abutted portions of the outside face of the hydrogen tank20support the hydrogen tank20, the hydrogen tank20and the tank abutting portions94,204are in constant contact with each other. This enables the hydrogen tank20to be retained in a specific position, and enables the hydrogen tank20to be stably supported, thereby enabling the hydrogen tank20to be suppressed from vibrating. This enables impact force acting on the hydrogen tank20due to vibration to be alleviated, thereby enabling the impact resistant structure of the hydrogen tank20to be improved by a simple structure.

Seventh Exemplary Embodiment

Explanation follows regarding a seventh exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 12. Note that similar configuration portions to the first to sixth exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the seventh exemplary embodiment has the same basic configuration as the first exemplary embodiment, with a feature that a shock absorbing space131is provided at each first shock absorbing section46.

Namely, as illustrated inFIG. 12, each first shock absorbing section46is provided between the member upright wall portion52at the vehicle inside of the floor cross member50at a location at which the tank bands24are provided, and the outside face of the hydrogen tank20. A space is made by providing the shock absorbing space131at the first shock absorbing section46. Note that the location is not limited to the location where the tank bands24are attached to the floor cross member50, and the shock absorbing space131may be provided at the first shock absorbing section46at a location where the tank bands24are attached to the floor reinforcement26.

Operation and Advantageous Effects of Seventh Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the seventh exemplary embodiment.

As illustrated inFIG. 12, in the present exemplary embodiment, each first shock absorbing section46is provided between the hydrogen tank20housed inside the floor tunnel14, and the floor cross member50,51(floor reinforcement26) attached to the floor panel12. Generally, in a vehicle side-on collision, when collision load along the vehicle width direction from the vehicle width direction outside is input to the floor panel12, the floor panel12and the floor cross member50,51(floor reinforcement26) attached to the floor panel12are displaced along the vehicle width direction and abut the hydrogen tank20. Impact force from the floor cross member50,51(floor reinforcement26) thereby acts on the hydrogen tank20. However, in the present exemplary embodiment, the floor cross member50,51(floor reinforcement26) is separated from the hydrogen tank20by the first shock absorbing section46, thereby enabling impact force acting on the hydrogen tank20from the floor cross member50,51(floor reinforcement26) to be alleviated. This enables the impact resistant structure of the hydrogen tank20to be formed by a simple structure. This enables the hydrogen tank20to have a lighter weight and a lower cost.

The respective vehicle width direction end portions of the tank bands24are fastened to one floor cross member50(floor reinforcement26, floor cross member51) in the vehicle width direction, and to the other floor cross member50(floor reinforcement26, floor cross member51) provided at the opposite side. Thus, when collision load along the vehicle width direction is input to the floor panel12from the vehicle width direction outside in a vehicle side-on collision, collision load is transmitted from one floor cross member50(floor reinforcement26, floor cross member51) to the other floor cross member50(floor reinforcement26, floor cross member51) through the tank bands24. This enables collision load acting directly on the hydrogen tank20to be reduced.

Note that in the present exemplary embodiment, each tank band24is configured as a single component; however, configuration is not limited thereto, and configuration may be applied with a separated structure. Moreover, a configuration may be applied in which the tank abutting member80is provided at the tank bands24.

Eighth Exemplary Embodiment

Explanation follows regarding an eighth exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 13toFIGS. 15. Note that similar configuration portions to the first to seventh exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted.

A vehicle lower section structure according to the eighth exemplary embodiment is a supplementary configuration to the first to seventh exemplary embodiments, with a feature that a tank protection plate134is provided at the vehicle lower side of the hydrogen tank20.

Namely, as illustrated inFIG. 13, the tank protection plate134is provided at the vehicle lower side of the hydrogen tank20that is attached to the floor panel12by the tank bands24. The tank protection plate134includes a pair of protection panel side wall portions135, a protection panel bottom wall portion136that couples together respective vehicle lower side end portions of the protection panel side wall portions135, and protection panel flange portions133that extend from vehicle upper side end portions of the protection panel side wall portions135, so as to separate from each other along the vehicle width direction. A cross-section profile of the tank protection plate134orthogonal to the vehicle front-rear direction thereby configures a hat shape. As illustrated inFIG. 14A, each protection panel flange portion133of the tank protection plate134abuts the reinforcement bottom wall portion38of the floor reinforcement26from the vehicle lower side. The bolt22is inserted through the reinforcement fastening hole39of the reinforcement bottom wall portion38, and a protection panel fastening hole138formed piercing through the protection panel flange portion133in the plate thickness direction, and the bolt22is fastened to the nut42. The protection panel flange portion133is thereby attached to the floor reinforcement26, and accordingly to the floor panel12. Note that, as illustrated inFIG. 14B, at a location where the tank band24is attached, each protection panel flange portion133of the tank protection plate134is bent so as to cover the tank band24, and the bolt22that fastens the tank band24to the floor reinforcement26, from the vehicle lower side.

As illustrated inFIG. 15B, a raised portion142is formed at a front end portion140of the tank protection plate134. The raised portion142extends along the vehicle up-down direction toward the vehicle upper side from the front end portion140and is separated from a front end portion of the hydrogen tank20. Thus, in cases in which collision load is input from the vehicle front side, the raised portion142bears the collision load, thereby enabling the impact acting on the hydrogen tank20to be alleviated. Moreover, as illustrated inFIG. 15C, a raised portion142is also formed at a rear end portion144of the tank protection plate134, similarly to at the front end portion140of the tank protection plate134. Thus, in cases in which collision load is input from the vehicle rear side, the raised portion142bears the collision load, thereby enabling the impact acting on the hydrogen tank20to be alleviated.

The tank protection plate134is not limited to a configuration in which the hydrogen tank20is covered from the vehicle lower side by a single member, and as illustrated by a first to a fourth modified example illustrated inFIG. 16AtoFIG. 16D, a configuration of plural members may be applied. Namely, a tank protection plate132of the first modified example illustrated inFIG. 16Ais configured by a first front side protection panel146and a first rear side protection panel148. The first front side protection panel146and the first rear side protection panel148are fastened to the floor reinforcements26, or the like by the bolts22, in a state in which a rear end portion of the first front side protection panel146and a front end portion of the first rear side protection panel148overlap each other. Namely, configuration is such that the entire lower face of the hydrogen tank20, including the tank bands24, is covered. This enables the respective sizes of the first front side protection panel146and the first rear side protection panel148to be smaller than in cases of configuration by a single panel, thereby facilitating handling when assembling the tank protection plate132, and enabling the hydrogen tank20to be reliably protected.

A tank protection plate129of the second modified example illustrated inFIG. 16Bis configured by a second front side protection panel150and a second rear side protection panel152. The second front side protection panel150and the second rear side protection panel152are fastened to the floor reinforcements26, or the like by the bolts22, in a state in which a rear end portion of the second front side protection panel150and a front end portion of the second rear side protection panel152face each other. This enables the respective sizes of the second front side protection panel150and the second rear side protection panel152to be smaller than in cases of configuration by a single panel, thereby facilitating handling when assembling the tank protection plate129, and facilitating the attachment operation.

A tank protection plate139of the third modified example illustrated inFIG. 16Cis configured by a third front side protection panel154, a third intermediate protection panel156, and a third rear side protection panel158. The third front side protection panel154and the third intermediate protection panel156are fastened to the floor reinforcements26, or the like by the bolts22, in a state in which a rear end portion of the third front side protection panel154, and a front end portion of the third intermediate protection panel156face each other at the vehicle lower side of the tank band24that is provided at a vehicle front side. The third intermediate protection panel156and the third rear side protection panel158are fastened to the floor reinforcements26, or the like by the bolts22, in a state in which a rear end portion of the third intermediate protection panel156, and a front end portion of the third rear side protection panel158face each other at the vehicle lower side of the tank band24that is provided at a vehicle rear side. Namely, this enables the respective individual sizes of the third front side protection panel154, the third intermediate protection panel156, and the third rear side protection panel158to be made smaller, in a configuration in which substantially the entire lower face of the hydrogen tank20, including the tank bands24, is covered. This further facilitates handling when assembling the tank protection plate139, and enables the hydrogen tank20to be reliably protected.

A tank protection plate141of the fourth modified example illustrated inFIG. 16Dis configured by a fourth front side protection panel160, a fourth intermediate protection panel162, and a fourth rear side protection panel164. The fourth front side protection panel160and the fourth intermediate protection panel162are fastened to the floor reinforcements26, or the like by the bolts22at the vehicle lower side of the tank band24, in a state in which the tank band24is interposed between a rear end portion of the fourth front side protection panel160and a front end portion of the fourth intermediate protection panel162. The fourth intermediate protection panel162and the fourth rear side protection panel164are fastened to the floor reinforcements26, or the like by the bolts22at the vehicle lower side of the tank band24, in a state in which the tank band24is interposed between a rear end portion of the fourth intermediate protection panel162and a front end portion of the fourth rear side protection panel164. This suppresses the surface of the hydrogen tank20from being exposed at the vehicle exterior, and enables the respective individual sizes of the fourth front side protection panel160, the fourth intermediate protection panel162, and the fourth rear side protection panel164to be made even smaller. This further facilitates handling when assembling the tank protection plate141, and further facilitates the attachment operation.

Operation and Advantageous Effects of Eighth Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the eighth exemplary embodiment.

As illustrated inFIG. 14A, in the present exemplary embodiment, the hydrogen tank20is covered from the vehicle lower side by the tank protection plate134, such that, as illustrated inFIG. 14C, impact force input to the vehicle10from below the vehicle by an obstacle or the like is input to the tank protection plate134. Namely, not only during a vehicle side-on collision, impact force from below the vehicle can also be alleviated by the tank protection plate134without being directly transmitted to the hydrogen tank20. This enables the impact acting on the hydrogen tank20to be further alleviated.

Ninth Exemplary Embodiment

Explanation follows regarding a ninth exemplary embodiment of a vehicle lower section structure according to the present invention, with reference toFIG. 17AtoFIG. 17D. Note that similar configuration portions to the first to eighth exemplary embodiments, etc. previously described are appended with the same reference numerals, and explanation thereof is omitted

A vehicle lower section structure according to the ninth exemplary embodiment has the same basic configuration as the eighth exemplary embodiment, with a feature that a tank protection plate166includes plural plates in the vehicle up-down direction.

Namely, as illustrated inFIG. 17A, the tank protection plate166is configured by a first outer panel168serving as an outer panel, and a first inner panel170serving as an inner panel. The first outer panel168includes a pair of outer side wall portions169, an outer bottom wall portion172that couples together respective vehicle lower side end portions of the outer side wall portions169, and outer flange portions173that extend from vehicle upper side end portions of the outer side wall portions169, so as to separate from each other along the vehicle width direction. A cross-section profile of the first outer panel168orthogonal to the vehicle front-rear direction is thereby formed in a hat shape. Each outer flange portion173of the first outer panel168abuts the reinforcement bottom wall portion38of the floor reinforcement26from the vehicle lower side. The bolt22is inserted through the reinforcement fastening hole39of the reinforcement bottom wall portion38, and an outer fastening hole, not illustrated in the drawings, piercing through the outer flange portion173in the plate thickness direction, and the bolt22is fastened to the nut42. The outer flange portion173is thereby attached to the floor reinforcement26, and accordingly to the floor panel12.

The first inner panel170includes a pair of inner side wall portions171, an inner bottom wall portion176that couples together respective vehicle lower side end portions of the inner side wall portions171and extends along the vehicle width direction, and a tank abutting portion178serving as a tank support portion that is formed at the vehicle width direction central portion of the inner bottom wall portion176. A cross-section profile of the first inner panel170orthogonal to the vehicle front-rear direction is thereby formed in substantially a U-shape. Each inner side wall portion171is joined to a vehicle width direction inside face of the outer side wall portion169, such that the first inner panel170and the first outer panel168are configured as an integral unit. The tank abutting portion178has substantially the same shape as an abutted portion of the shape of the outer peripheral face of the hydrogen tank20.

A deformation absorption section180is provided between the first inner panel170and the first outer panel168. The deformation absorption section180is a space surrounded by the pair of outer side wall portions169, the outer bottom wall portion172, the inner bottom wall portion176, and the tank abutting portion178. Note that the size of the deformation absorption section180may be modified as appropriate. For example, as in a first modified example illustrated inFIG. 17B, a modified shape may be applied in which an outer bottom wall portion190of a first outer panel188is moved toward the vehicle lower side. As in a second modified example illustrated inFIG. 17C, a first outer panel192may be formed in a flat plate shape, and a first inner panel194formed in substantially a hat shape.

As illustrated inFIG. 17A, in the present exemplary embodiment, the tank protection plate166is configured by two components, these being the first inner panel170and the first outer panel168; however, configuration is not limited thereto. As illustrated in a modified example inFIG. 17D, configuration may be made by three components, these being a second outer panel182, a second inner panel184that abuts the hydrogen tank20, and a second intermediate member186that is provided between the second outer panel182and the second inner panel184and includes protruding shapes toward the vehicle upper side. In such cases, a space196formed by the second intermediate member186configures a deformation absorption section. The tank protection plate166may also be configured by more than three components.

Operation and Advantageous Effects of Ninth Exemplary Embodiment

Explanation follows regarding operation and advantageous effects of the ninth exemplary embodiment.

As illustrated inFIG. 17A, in the present exemplary embodiment, the deformation absorption section180is provided between the hydrogen tank20and the tank protection plate166. Thus, even if the tank protection plate166deforms so as to project out toward the vehicle upper side due to impact force input to the vehicle10from below the vehicle by an obstacle or the like, the tank protection plate166and the hydrogen tank20are suppressed from abutting each other, thereby enabling the impact force acting on the hydrogen tank20from the tank protection plate166to be alleviated.

Since the tank abutting portion178that is formed in the same shape as an abutted portion of the outside face of the hydrogen tank20supports the hydrogen tank20, the hydrogen tank20and the tank abutting portion178are in constant contact with each other. This enables the hydrogen tank20to be retained in a specific position, and enables the hydrogen tank20to be stably supported, thereby enabling the hydrogen tank20to be suppressed from vibrating. This enables impact force acting on the hydrogen tank20due to vibration to be alleviated, thereby enabling the impact resistant structure of the hydrogen tank20to be improved by a simple structure.

Note that in the first to ninth exemplary embodiments described above, the hydrogen tank20that stores hydrogen internally is given as an example of a tank; however, configuration is not limited thereto, and the tank may be a gas tank that stores gas, or a tank that stores another substance.

Exemplary embodiments of the present invention have been explained above; however, the present invention is not limited to the above, and obviously various other modifications may be implemented within a range not departing from the scope of the present invention.