Patent ID: 12233699

DETAILED DESCRIPTION

An embodiment of the present disclosure will be described below in detail with reference to the accompanying drawings. The following description of the preferable embodiment is merely exemplary in essence and not intended to limit the present disclosure, its application, nor its usage.

FIG.1is a side view of an automobile1including a vehicle-body structure A according to the embodiment of the present disclosure when viewed from left. In describing the embodiment, a vehicle front-rear direction is simply referred to as a “front-rear direction”, a vehicle front side is simply referred to as a “front side”, and a vehicle “rear side” is simply referred to as a “rear side”. In addition, a vehicle width direction is the right-left direction of the vehicle, a vehicle left side is simply referred to as a “left side”, and a vehicle right side is simply referred to as a “right side”.

Entire Structure of Automobile

In some embodiments, the automobile1is a passenger automobile, and an occupant space R1in which a passenger boards is provided at a front-rear direction intermediate portion of the automobile1. The occupant space R1includes front seats (front-row seats) FS included in a front row, and rear seats (rear-row seats) RS included in a rear row. The front seats FS include a driver seat arranged on the right side (or the left side) in the occupant space R1, and a front passenger seat arranged on the left side (or the right side) in the occupant space R1. The rear seats RS are arranged on the right and left sides, respectively, in the occupant space R1. Although not illustrated, third-row seats may be arranged on the rear side of the rear seats RS. Alternatively, the rear seats RS may be omitted.

A front door FD and a rear door RD are disposed on each of the left and right sides of the occupant space R1. The rear door RD may be omitted in a case of the automobile1including no rear seats RS.

As illustrated in the embodiment ofFIG.1, a front-side space R2is provided on the front side of the occupant space R1in the automobile1. A powertrain PT can be mounted in the front-side space R2as necessary. When the powertrain PT is mounted in the front-side space R2, the front-side space R2may be called, for example, a powertrain storage room, a motor room, or an engine room. A bonnet hood BF is provided at an upper portion of the front-side space R2.

A trunk space R3in which a package or the like can be housed may be provided on the rear side of the occupant space R1in the automobile1. The trunk space R3can be opened and closed by a trunk lid TR. A rear-side space R4may be provided on the rear side of the occupant space R1and at a position lower than the trunk space R3in the automobile1. The powertrain PT that generates power for the automobile1can be mounted in the rear-side space R4as necessary. When the powertrain PT is mounted in the rear-side space R4, the rear-side space R4may be called, for example, a powertrain storage room, a motor room, or an engine room.

The powertrain PT may be mounted in each of the front-side space R2and the rear-side space R4or the powertrain PT may be mounted in one of them. A front-wheel-drive vehicle in which only front wheels FT are driven by the powertrain PT is achieved when the powertrain PT is mounted only in the front-side space R2, or a rear-wheel-drive vehicle in which only rear wheels RT are driven by the powertrain PT is achieved when the powertrain PT is mounted only in the rear-side space R4. Alternatively, a four-wheel-drive vehicle is achieved when the front wheels FT and the rear wheels RT are driven by the powertrains PT mounted in both the front-side space R2and the rear-side space R4.

Each powertrain PT includes at least a traveling motor M (illustrated inFIG.2) for driving a drive wheel and also includes a speed reducer, a transmission, or the like as necessary. Thus, the automobile1is an electric vehicle. The traveling motor M is disposed such that the rotation center thereof extends in the right-left direction. The powertrain PT may include, for example, a controller in addition to the traveling motor M. The powertrain PT may include an internal combustion engine. A battery unit Y (also illustrated inFIG.1) for supplying electric power to the traveling motor M is mounted at a lower portion of the automobile1. For example, the battery unit Y may be charged by using power generated by the internal combustion engine, and either the front wheels FT or the rear wheels RT or both may be driven by power generated by the internal combustion engine.

The type of the automobile1does not necessarily need to be a four-door vehicle as exemplarily illustrated inFIG.1and may be, for example, an automobile including no rear doors RD. The present disclosure is also applicable to an automobile, such as a hatchback vehicle, in which the rear-side space R4can be opened and closed by a tail gate.

As illustrated inFIG.2, the automobile1includes a lower-portion structural body2and an upper-portion structural body3, and the vehicle-body structure A is constituted by the lower-portion structural body2and the upper-portion structural body3.FIG.2illustrates a state in which the doors FD and RD, the bonnet hood BF, a fender, window glasses, a roof, a center pillar, a rear pillar, a bumper, front and rear lighting devices, an instrument panel, the front and rear seats, and the like, which are included in the upper-portion structural body3when the automobile is assembled, are removed.FIG.2also illustrates a state in which the front wheels FT, the rear wheels RT, a suspension device, and the like, which are included in the lower-portion structural body2when the automobile is assembled, are removed.

The lower-portion structural body2includes the battery unit Y. The battery unit Y includes a front-side battery FB, a rear-side battery RB, and a rack frame10surrounding the front-side battery FB and the rear-side battery RB. The lower-portion structural body2also includes a front support frame20extending from a front portion of the rack frame10toward the front side, and a rear support frame30extending from a rear portion of the rack frame10toward the rear side.

In a typical electric automobile, a battery unit is often detachably attached as a separated body from a vehicle body under a floor; but, in the embodiment ofFIG.2, not only the batteries FB and RB but also the front support frame20and the rear support frame30are integrated with the rack frame10surrounding the batteries FB and RB, and the front support frame20and the rear support frame30are detachably attached to the upper-portion structural body3together with the batteries FB and RB.

Specifically, as illustrated inFIG.2, in some embodiments, the automobile1may be configured to be dividable in the up-down direction into the lower-portion structural body2including the batteries FB and RB, and the upper-portion structural body3in which the occupant space R1and the trunk space R3are formed. When the structure is divided in the up-down direction, integration of the lower-portion structural body2with the upper-portion structural body3may be achieved by using fastening members such as bolts and nuts, screws, and the like without using welding, bonding, and the like. Accordingly, the lower-portion structural body2can be separated from the upper-portion structural body3as necessary when maintenance and repair are performed after the automobile1is handed over to a user, thereby making it easier to maintain the vehicle than in conventional electric automobiles.

It is known to use a vehicle-body structure of a ladder-frame type for an automobile. In a case of the vehicle-body structure of the ladder-frame type, division into a ladder-frame and a cabin in the up-down direction is possible, but the ladder-frame continuously extends in the front-rear direction and thus mainly receives a collision load during a front-end collision or a rear-end collision. In the event of a side collision, the ladder-frame only supplementarily receives a collision load, and the collision load is mainly received by the cabin. In this manner, in the vehicle-body structure of the ladder-frame type, it is normal that a member that receives a collision load during a front-end or a rear-end collision is different than during a side collision.

However, in a case of the automobile1of the embodiment illustrated inFIG.2, the lower-portion structural body2, which includes the front support frame20and the rear support frame30, and the upper-portion structural body3can be divided from each other. The technical idea of this divided structure is largely different from that of the conventional vehicle-body structure of the ladder-frame type, because a collision load is received by the lower-portion structural body2and the upper-portion structural body3in both cases of front or rear collision and side collision and thus the collision load can be dispersed to and absorbed by the structural bodies2and3, which improves vehicle safety during collisions when compared to conventional ladder-frame type vehicles.

Hereinafter, the structures of the lower-portion structural body2and the upper-portion structural body3will be sequentially described.

Lower-Portion Structural Body

First, the lower-portion structural body2will be described below. The lower-portion structural body2includes the powertrain PT, the front wheels FT, the rear wheels RT, and front-side suspension devices SP1and SP2and rear-side suspension devices SP3and SP4, which are illustrated with virtual lines inFIG.4, in addition to the batteries FB and RB, the rack frame10, the front support frame20, and the rear support frame30. The formats of the front-side suspension devices SP1and SP2and the rear-side suspension devices SP3and SP4are not particularly limited, and the vehicle-body structure may be changed in accordance with the formats of the front-side suspension devices SP1and SP2and the rear-side suspension devices SP3and SP4.

As illustrated inFIG.2, the rack frame10as a framework of the battery unit Y is a member for surrounding and protecting the front-side battery FB, the rear-side battery RB, harnesses, and the like. The rack frame10is formed in such a large size that, on the lower side of an occupant-space-side floor panel41to be described later, the rack frame10extends from the vicinity of a left end portion of the occupant-space-side floor panel41to the vicinity of a right end portion thereof and extends from the vicinity of a front end portion of the occupant-space-side floor panel41to the vicinity of a rear end portion thereof. In this manner, since the rack frame10is provided in a large part of a region on the lower side of the occupant-space-side floor panel41, the batteries FB and RB having large capacities can be mounted on the automobile1. The batteries FB and RB may be, for example, lithium-ion batteries or all-solid-state batteries or may be any other secondary batteries. Alternatively, the batteries FB and RB may be what is called battery cells or may be battery packs in which a plurality of battery cells are housed.

The rack frame10includes a left-side member11, a right-side member12, a front-side member13, and a rear-side member14. The left-side member11, the right-side member12, the front-side member13, and the rear-side member14are formed of, for example, an extruded material made of an aluminum alloy, but may be formed of a press-formed material such as an aluminum alloy plate material or a steel plate. In description below, an “extruded material” is an extruded material made of an aluminum alloy, and a “press-formed material” is a press-formed material such as an aluminum alloy plate material or a steel plate. Alternatively, each member may be formed of, for example, cast metal or die cast.

A cross-sectional shape of each of the left-side member11, the right-side member12, the front-side member13, and the rear-side member14in a direction orthogonal to its longitudinal direction is a rectangular shape. The left-side member11, the right-side member12, the front-side member13, and the rear-side member14are all arranged at the same height and substantially horizontally extend. When the lower-portion structural body2is to be connected to the upper-portion structural body3, the front-side member13is fastened and fixed to a lower portion of a dash panel50by a fastening member, and the left-side member11and the right-side member12are fastened and fixed to right and left side sills60, respectively, by fastening members. The rear-side member14is fastened and fixed to a connection panel43, which will be described later, by a fastening member.

The left-side member11is provided at a left end portion of the lower-portion structural body2and extends in the front-rear direction. The right-side member12is provided at a right end portion of the lower-portion structural body2and extends in the front-rear direction. The left-side member11and the right-side member12are arranged on a vehicle-width-direction inner side of the right and left side sills60, respectively, to be described later. As illustrated in, for example,FIG.5, the front-side member13is provided at a front portion of the battery unit Y and extends in the right-left direction from a front end portion of the left-side member11to a front end portion of the right-side member12. A left end portion of the front-side member13and the front end portion of the left-side member11are connected to each other, and a right end portion of the front-side member13and the front end portion of the right-side member12are connected to each other. The rear-side member14is provided at a rear portion of the battery unit Y and extends in the right-left direction from a rear end portion of the left-side member11to a rear end portion of the right-side member12. A left end portion of the rear-side member14and the rear end portion of the left-side member11are connected to each other, and a right end portion of the rear-side member14and the rear end portion of the right-side member12are connected to each other.

A cover member15as a bottom plate is attached to a lower portion of the rack frame10. The rack frame10is blocked from the lower side by the cover member15. The cover member15substantially horizontally extends and is fixed to lower surfaces of the left-side member11, the right-side member12, the front-side member13, and the rear-side member14and also fixed to the side sills60as described later. Note that an upper portion of the rack frame10may be blocked by a non-illustrated lid or may be blocked by the occupant-space-side floor panel41to be described later. Note that electric power of the batteries FB and RB housed in the rack frame10is supplied to the traveling motor M through a non-illustrated traveling control circuit. The batteries FB and RB can be charged through a non-illustrated charging socket.

As illustrated inFIG.6, a front part inside of the rack frame10is referred to as a front-side battery housing portion200in which the front-side battery FB is housed, and a rear part inside of the rack frame10is referred to as a rear-side battery housing portion201in which the rear-side battery RB is housed. A part between the front-side battery housing portion200and the rear-side battery housing portion201is a part in which no battery is housed, and this part in which no battery is housed is referred to as battery non-housing portion202. In other words, the front-side battery housing portion200, the battery non-housing portion202, and the rear-side battery housing portion201are provided alongside each other (in other words, adjacent to each other) in the front-rear direction. Note that one of the front-side battery housing portion200and the rear-side battery housing portion201may be omitted in some embodiments.

FIG.5illustrates a cross-section of a right-left direction central portion of the vehicle-body structure A. As illustrated inFIG.5, first to third battery-side cross members10A,10B, and10C formed as hollow members are provided inside the rack frame10as reinforcement members extending in the right-left direction. The heights of the first to third battery-side cross members10A,10B, and10C are all the same and are the same as the heights of the front-side member13and the rear-side member14. The first to third battery-side cross members10A,10B, and10C may be formed of extruded materials or may be formed of press-formed materials. In the present embodiment, the three battery-side cross members10A,10B, and10C are provided, but the number of the battery-side cross members10A,10B, and10C may be increased or decreased in accordance with dimensions of the rack frame10in the front-rear direction.

The first to third battery-side cross members battery-side cross members10A,10B, and10C are arranged at an interval from each other in the front-rear direction, the first battery-side cross member10A is positioned farthest on the front side, and the third battery-side cross member10C is positioned farthest on the rear side. Lower portions of the battery-side cross members10A,10B, and10C are fixed to an upper surface of the cover member15. Left end portions of the battery-side cross members10A,10B, and10C are fixed to an inner surface (right-side surface) of the left-side member11, and right end portions of the battery-side cross members10A,10B, and10C are fixed to an inner surface (left-side surface) of the right-side member12. In other words, the battery-side cross members10A,10B, and10C are members connecting the left-side member11and the right-side member12.

A front-portion central member16and first to third rear-portion central members17to19as hollow reinforcement members extending in the front-rear direction are provided inside the rack frame10. The front-portion central member16and the first to third rear-portion central members17to19may be referred to as a battery frame extending in the front-rear direction, and the battery unit Y has a structure including the battery frame constituted by the front-portion central member16, the first to third rear-portion central members17to19, and the like. The left-side member11, the right-side member12, the front-side member13, and the rear-side member14may be included in the battery frame.

The front-portion central member16and the first to third rear-portion central members17to19are arranged at substantially same heights and provided at a right-left direction center of the rack frame10. Lower end portions of the front-portion central member16and the first to third rear-portion central members17to19are attached to the upper surface of the cover member15. The front-portion central member16and the first to third rear-portion central members17to19extend from the front-side member13to the rear-side member14.

The front-portion central member16is a front-side first frame portion disposed at the front-side battery housing portion200and is arranged between the front-side member13and the first battery-side cross member10A. A front end portion of the front-portion central member16is fixed to a right-left direction central portion of the front-side member13, and a rear end portion of the front-portion central member16is fixed to a right-left direction central portion of the first battery-side cross member10A. Accordingly, the front-side member13is a member extending to connect the front end portions of the left-side member11and the right-side member12to the front end portion of the front-portion central member16.

The first rear-portion central member17is a front-side first frame portion disposed at the front-side battery housing portion200on the rear side of the front-portion central member16and is arranged between the first battery-side cross member10A and the second battery-side cross member10B. A front end portion of the first rear-portion central member17is fixed to the right-left direction central portion of the first battery-side cross member10A, and a rear end portion of the first rear-portion central member17is fixed to a right-left direction central portion of the second battery-side cross member10B.

The second rear-portion central member18is a second frame portion disposed at the battery non-housing portion202on the rear side of the first rear-portion central member17and is arranged between the second battery-side cross member10B and the third battery-side cross member10C. A front end portion of the second rear-portion central member18is fixed to the right-left direction central portion of the second battery-side cross member10B, and a rear end portion of the second rear-portion central member18is fixed to a right-left direction central portion of the third battery-side cross member10C.

The third rear-portion central member19is a rear-side first frame portion disposed at the rear-side battery housing portion201on the rear side of the second rear-portion central member18and is arranged between the third battery-side cross member10C and the rear-side member14. A front end portion of the third rear-portion central member19is fixed to the right-left direction central portion of the third battery-side cross member10C, and a rear end portion of the third rear-portion central member19is fixed to a right-left direction central portion of the rear-side member14.

Accordingly, the first to third battery-side cross members10A,10B, and10C and the front-portion central member16and the first to third rear-portion central members17to19are disposed in a lattice shape and connected to each other inside the rack frame10, which further increases the effect of reinforcing the rack frame10and thus the effect of reinforcing the lower-portion structural body2.

When a virtual straight line extending in the front-rear direction in a plan view is assumed, the positions of the front-portion central member16and the first to third rear-portion central members17to19in the right-left direction are set such that the members are arranged on the virtual line. In other words, the members are provided such that the first to third rear-portion central members17to19are positioned on a virtual extended line from the front-portion central member16on the rear side.

FIG.7is a cross-sectional diagram along line A-A inFIG.6and illustrates a section corresponding to the front-side battery housing portion200. The front-side battery FB is housed on each of the right and left sides of the first rear-portion central member17provided in the rack frame10. A first harness204extending in the front-rear direction is disposed below the first rear-portion central member17. The first harness204extends from the front portion of the rack frame10to the rear portion thereof, and accordingly, is disposed extending in the front-rear direction through the lower side of the front-portion central member16and the first to third rear-portion central members17to19. In the present embodiment, two first harnesses204are disposed alongside each other in the vehicle width direction, but the present disclosure is not limited thereto and one first harness204may be provided or three or more first harnesses204may be provided.

FIG.8is a cross-sectional diagram along line B-B inFIG.6and illustrates a section corresponding to the battery non-housing portion202. The second rear-portion central member18is provided at the battery non-housing portion202. The second rear-portion central member18is larger in width than the first rear-portion central member17illustrated inFIG.7in the vehicle width direction. Specifically, the dimension of the second rear-portion central member18in the vehicle width direction is set to be longer than the dimension of the first rear-portion central member17in the vehicle width direction, the first rear-portion central member17and the second rear-portion central member18are arranged such that a left end portion of the second rear-portion central member18protrudes on the left side of a left end portion of the first rear-portion central member17and a right end portion of the second rear-portion central member18protrudes on the right side of a right end portion of the first rear-portion central member17when viewed in the front-rear direction. Accordingly, the width of a space210(illustrated inFIG.8) directly below the second rear-portion central member18is larger than the width of a space220(illustrated inFIG.7) directly below the first rear-portion central member17. Stiffness is likely to decrease at a part where the front-side battery FB and the rear-side battery RB are not positioned in some cases, but the second rear-portion central member18having a large width is provided at the part where the front-side battery FB and the rear-side battery RB are not positioned, and thus stiffness decrease can be suppressed. Note that the first rear-portion central member17and the second rear-portion central member18are arranged at the same height, and accordingly, the dimensions of the space210and the space220in the up-down direction are substantially equal.

A second harness205for a bus bar is disposed in addition to the first harness204below the second rear-portion central member18. The second harness205for a bus bar is a harness for connecting the front-side battery FB and the rear-side battery RB and thus extends in the front-rear direction, but is not provided at the front-side battery housing portion200and the rear-side battery housing portion201and passes through the battery non-housing portion202. The second harness205is positioned on each of the right and left sides of the first harness204. Accordingly, a larger number of harnesses204and205are disposed in the space210below the second rear-portion central member18than in the space220below the first rear-portion central member17, but the disposition of a large number of harnesses204and205causes no problem since the width of the space210is relatively large. The first harnesses204and the second harnesses205are not limited to the illustrated arrangement but may be optionally arranged.

As illustrated inFIG.2, a pair of right and left front support frames20are provided and connected to the front-side member13of the rack frame10. The front-side powertrain PT is attached to each front support frame20through a non-illustrated mounting member. In the lower-portion structural body2, drive shafts S1through which output from the powertrain PT (rotational force of the traveling motor M) is transferred to the right and left front wheels FT, respectively, are provided on the right and left sides.

Similarly to the front support frames20, a pair of right and left rear support frames30are provided and connected to the rear-side member14of the rack frame10. The rear-side powertrain PT is attached to each rear support frame30through a non-illustrated mounting member. In the lower-portion structural body2, drive shafts S2through which output from the powertrain PT (rotational force of the traveling motor M) is transferred to the right and left rear wheels, respectively, are provided on the right and left sides.

Upper-Portion Structural Body

Subsequently, the upper-portion structural body3will be described below. The upper-portion structural body3includes a floor member40, the dash panel50, and the pair of right and left-side sills60. The floor member40is a member arranged at a higher position than the rack frame10and the rear support frames30of the lower-portion structural body2. The floor member40includes the occupant-space-side floor panel (first floor panel)41constituting a floor of the occupant space R1including the front seats FS and the rear seats RS (illustrated inFIG.1) on which passengers sits, a trunk-space-side floor panel (second floor panel)42constituting a floor of the trunk space R3, and the connection panel43connecting a rear portion of the occupant-space-side floor panel41and a front portion of the trunk-space-side floor panel42.

The floor member40may be formed of, for example, a member shaped by pressing a steel plate or the like. The occupant-space-side floor panel41, the trunk-space-side floor panel42, and the connection panel43may be integrally formed or may be separately formed and then connected. In the present embodiment, description is made with the three divided portions of the occupant-space-side floor panel41, the trunk-space-side floor panel42, and the connection panel43, but the floor member40including the panels41to43may be referred to as a floor panel. Alternatively, only the occupant-space-side floor panel41may be referred to as a floor panel.

The occupant-space-side floor panel41extends from a front portion of the occupant space R1to a rear portion thereof and from a left-side portion of the occupant space R1to a right-side portion thereof. The occupant-space-side floor panel41according to the embodiment ofFIG.2has a floor tunnel-less structure including no tunnel portion. Specifically, a floor panel of a conventional automobile is typically provided with a tunnel portion largely bulging upward and extending in the front-rear direction. The tunnel portion is a portion for allowing, for example, insertion of an exhaust pipe extending toward a rear side from an engine mounted in an engine room at a vehicle front portion and insertion of a propeller shaft through which output from the engine is transferred to rear wheels. The diameters of the exhaust pipe and the propeller shaft are often, for example, equal to or larger than 10 cm, and furthermore, a gap of at least several centimeters or larger needs to be provided between each of the exhaust pipe and the propeller shaft and the floor panel to prevent interference of the exhaust pipe or the propeller shaft with the floor panel. In addition, for example, an insulator is disposed on an inner surface of the tunnel portion in some cases. With these factors, the height of the tunnel portion from the floor panel is, for example, equal to or larger than 15 cm or equal to or larger than 20 cm in some cases, and as for a positional relation with a seat, an upper end of the tunnel portion is higher than a lower end of a seat cushion on a seat rail or an up-down direction central portion of the seat cushion. A structure without such a tunnel portion largely bulging upward is a tunnel-less structure.

The occupant-space-side floor panel41includes no tunnel portion having a height equal to or larger than 15 cm or equal to or larger than 20 cm from an upper surface of the occupant-space-side floor panel41as described above, but may include, for example, a bulging portion having a low height equal to or smaller than 5 cm or equal to or smaller than 10 cm from the upper surface of the occupant-space-side floor panel41. In a case of such a bulging portion having a low height, neither exhaust pipe nor a propeller shaft can be inserted inside the bulging portion, and thus the bulging portion does not function as a tunnel portion. Thus, the occupant-space-side floor panel41, which includes a bulging portion having a low height equal to or smaller than 5 cm or equal to or smaller than 10 cm from the upper surface of the occupant-space-side floor panel41, is a floor panel of a tunnel-less structure.

In the present embodiment, since each powertrain PT includes the traveling motor M, no internal combustion engine needs to be mounted in the front side space R2and thus no exhaust pipe needs to be guided to the vehicle rear side. When a powertrain PT is mounted in the rear-side space R4, the rear wheels RT can be driven by the powertrain PT and a propeller shaft can be omitted. Accordingly, the occupant-space-side floor panel41can have a tunnel-less structure.

As illustrated inFIG.3as well, a recessed portion41aformed bulging downward is formed at a front-rear direction intermediate portion of the occupant-space-side floor panel41. Specifically, the recessed portion41aon which the feet of a passenger can be placed is formed at part of the occupant-space-side floor panel41, which corresponds to the battery non-housing portion202. The recessed portion41ahas a bottom surface41bon which the feet of a rear-seat passenger sitting on a rear seat RS can be placed. The bottom surface41bis substantially horizontally formed. A front-side part of the recessed portion41ais formed to be gradually deeper toward the rear side. The recessed portion41amay be continuously formed from a left side portion of the occupant-space-side floor panel41to a right side portion thereof. The bottom surface41bhas a height substantially same as that of a lower portion of the corresponding side sill60to be described later, and accordingly, the height of the bottom surface41bis sufficiently low. Accordingly, a passenger staying space can be expanded by using the battery non-housing portion202of the lower-portion structural body2.

The positional relation between the recessed portion41aand a seat cushion of each rear seat RS in the front-rear direction is set such that the feet of a rear-seat passenger sitting on the rear seat RS are naturally placed on the bottom surface41bwhen the feet are held directly downward. The position of a front portion of the recessed portion41ais set such that the feet of a rear-seat passenger sitting on the rear seat RS are placed on the bottom surface41bwhen the feet are moved obliquely forward. The position of the recessed portion41aand the dimension thereof in the front-rear direction are set such that the feet of a rear-seat passenger can be placed on the bottom surface41beven when the feet are moved somehow in the front-rear direction.

A floor frame41cextending in the front-rear direction is provided at a right-left direction central portion of the recessed portion41a. The floor frame41cis formed surrounding the second rear-portion central member18of the lower-portion structural body2from the upper side and the right and left sides, and the second rear-portion central member18is housed inside the floor frame41cfrom the lower side of the floor frame41cwhen the lower-portion structural body2and the upper-portion structural body3are integrated. A part at which the recessed portion41ais formed is reinforced since the floor frame41cis provided.

The trunk-space-side floor panel42is positioned higher than the occupant-space-side floor panel41. The rear-side space R4is positioned lower than the trunk-space-side floor panel42. In other words, the trunk-space-side floor panel42is arranged to separate the trunk space R3from the rear-side space R4. Since the trunk-space-side floor panel42is arranged at a higher position than the occupant-space-side floor panel41, the connection panel43extends in the up-down direction. The connection panel43may be vertical or may be tilted such that the connection panel43is positioned farther on the rear side at a position farther on the upper side.

As illustrated inFIG.5as well, the dash panel50is a member as a partition wall between the front side space R2and the occupant space R1and extends upward from a front portion of the occupant-space-side floor panel41and in the right-left direction as well, thereby partitioning the front portion of the occupant space R1.

As illustrated inFIG.4, the right and left side sills60are disposed extending in the front-rear direction at right and left end portions, respectively, of the occupant-space-side floor panel41. A left end portion of the occupant-space-side floor panel41is connected to an up-down direction intermediate portion of the left side sill60. Since the battery unit Y including the batteries FB and RB is disposed at a lower position than the occupant-space-side floor panel41, such arrangement is made that the lower part of the side sill60overlaps with the batteries FB and RB in a vehicle side view. Similarly, the right side sill60is connected to the right end portion of the occupant-space-side floor panel41.

As illustrated inFIG.3, the upper-portion structural body3includes a pair of right and left hinge pillars70. The right hinge pillar70extends upward from a front end portion of the right side sill60. The left hinge pillar70extends upward from a front end portion of the left side sill60. The right and left front doors FD (illustrated inFIG.1) are rotatably attached to the right and left hinge pillars70, respectively. A left edge portion of the dash panel50is connected to a right-side surface of the left hinge pillar70. A right edge portion of the dash panel50is connected to a left-side surface of the right hinge pillar70. Note that, although not illustrated, the upper-portion structural body3is also provided with a center pillar, a rear pillar, and the like.

As illustrated inFIG.2, a left-side front-wheel suspension support member51A that supports the suspension device (front suspension device) SP1(illustrated with virtual lines inFIG.4) for the left front wheel FT is provided on the left side on the front side of the dash panel50in the upper-portion structural body3. A right-side front-wheel suspension support member51B that supports the suspension device (front suspension device) SP2(illustrated with virtual lines inFIG.4) for the right front wheel FT is provided on the right side on the front side of the dash panel50in the upper-portion structural body3. The suspension devices SP1and SP2are not limited to a particular format but include suspension arms that freely swingably support the front wheels FT in the up-down direction, shock absorbers, springs, or the like. End portions of the suspension arms on the vehicle body side, upper end portions of the shock absorbers, or the like are attached to the front-wheel suspension support members51A and51B. The front-wheel suspension support members51A and51B can be made of, for example, aluminum die cast, but are not limited thereto and may be made of a combination of steel plates or the like.

As illustrated in, for example,FIG.2, three left-side fixation frames52A for fixing the left-side front-wheel suspension support member51A are provided on the left side on the front side of the dash panel50. The three left-side fixation frames52A are arranged at an interval from each other in the up-down direction, and front portions of the three left-side fixation frames52A are fixed to the front-wheel suspension support member51A. Rear portions of the left-side fixation frames52A arranged uppermost and at an up-down direction intermediate position are fixed to the left-side hinge pillar70and the left side of the dash panel50. A rear portion of the left-side fixation frame52A arranged lowermost is fixed to the left side sill60.

As partially illustrated inFIG.3, three right-side fixation frames52B for fixing the right-side front-wheel suspension support member51B are provided on the right side on the front side of the dash panel50. The three right-side fixation frames52B are arranged at an interval from each other in the up-down direction, and front portions of the three right-side fixation frames52B are fixed to the front-wheel suspension support member51B. Rear portions of the right-side fixation frames52B arranged uppermost and at an up-down direction intermediate position are fixed to the right-side hinge pillar70and the right side of the dash panel50. A rear portion of the right-side fixation frame52B arranged lowermost is fixed to the right side sill60.

As illustrated inFIG.2, a left-side crush can53A extending toward the front side is fixed to a front portion of the left-side front-wheel suspension support member51A. A right-side crush can53B extending toward the front side is fixed to a front portion of the right-side front-wheel suspension support member51B. A bumper reinforcement140extending in the right-left direction is attached to a front portion of the left-side crush can53A and a front portion of the right-side crush can53B.

As illustrated inFIG.4, the upper-portion structural body3includes a left-side front frame54A and a right-side front frame54B. Specifically, the left-side front frame54A connecting a front portion of a center frame80to be described later and the left-side front-wheel suspension support member51A, and the right-side front frame54B connecting the front portion of the center frame80and the right-side front-wheel suspension support member51B are provided on the front side of the dash panel50. The left-side front frame54A is tilted such that the left-side front frame54A is positioned farther on the left side at a position farther on the front side. The right-side front frame54B is tilted such that the right-side front frame54B is positioned farther on the right side at a position farther on the front side.

The occupant-space-side floor panel41includes a front-portion cross member44A, an intermediate cross member44B, a recessed-portion front-side cross member44C, and a recessed-portion rear-side cross member44D. The front-portion cross member44A, the intermediate cross member44B, the recessed-portion front-side cross member44C, and the recessed-portion rear-side cross member44D extend in the right-left direction and are fixed to the upper surface of the occupant-space-side floor panel41. Thus, the front-portion cross member44A, the intermediate cross member44B, the recessed-portion front-side cross member44C, and the recessed-portion rear-side cross member44D are disposed such that the members intersect with the center frame80, which will be described later, in a plan view in the occupant space R1.

The front-portion cross member44A is disposed at the front portion of the occupant-space-side floor panel41. A front portion of the front-portion cross member44A is also joined to the lower portion of the dash panel50. The intermediate cross member44B is disposed on the rear side of the front-portion cross member44A and on the front side of the recessed portion41a, and a closed cross-section is constituted by the intermediate cross member44B and the occupant-space-side floor panel41.

The recessed-portion front-side cross member44C is disposed extending in the right-left direction along the front portion of the recessed portion41aon the rear side of the intermediate cross member44B. The projecting-portion rear-side cross member44D is disposed extending in the right-left direction along a rear portion of the recessed portion41aon the rear side of the recessed-portion front-side cross member44C. A closed cross-section is constituted by the recessed-portion front-side cross member44C and the occupant-space-side floor panel41, and a closed cross-section is constituted by the recessed-portion rear-side cross member44D and the occupant-space-side floor panel41. Since the recessed-portion front-side cross member44C and the recessed-portion rear-side cross member44D are provided, the part at which the recessed portion41ais formed can be reinforced. A front portion of the floor frame41cprovided inside the recessed portion41ais connected to a right-left direction central portion of the recessed-portion front-side cross member44C, and a rear portion of the floor frame41cis connected to a right-left direction central portion of the recessed-portion rear-side cross member44D.

As illustrated in, for example,FIG.5, the upper-portion structural body3includes the center frame80continuously extending in the front-rear direction from the dash panel50to the connection panel43. The center frame80is positioned at a right-left direction central portion. Specifically, the disposition positions of the front-portion central member16and the first to third rear-portion central members17to19and the center frame80are set to have a positional relation in which the front-portion central member16and the first to third rear-portion central members17to19each overlaps with the center frame80in a plan view.

The center frame80is disposed to be higher than and away from the occupant-space-side floor panel41at a right-left direction central portion of the occupant space R1. A rear portion of the center frame80is connected to the connection panel43. The left-side front seat FS and a rear seat RS are disposed on the left side of the center frame80, and the right-side front seat FS and a rear seat RS are disposed on the right side of the center frame80.

Since the center frame80is arranged to be higher than and away from the occupant-space-side floor panel41, components and the like can be disposed in a space between a lower surface of the center frame80and the upper surface of the occupant-space-side floor panel41. Alternatively, the space between the lower surface of the center frame80and the upper surface of the occupant-space-side floor panel41can be used as an object housing unit. As illustrated inFIG.5, the center frame80according to the present embodiment includes a bend portion80A that bends in the up-down direction at a front-rear direction intermediate portion. Since the bend portion80A is provided in the center frame80, for example, a rear-side part can be positioned lower than a front-side part, and thus comfort of rear-seat passengers can be improved. Since the front-side part of the center frame80can be positioned higher than the rear-side part, an object or the like can be arranged at a lower position than the front-side part of the center frame80. The bend portion80A is formed at a site on the front side of a front-rear direction central portion of the center frame80.

Specifically, the center frame80includes a front-side frame member81extending in the front-rear direction, a rear-side frame member82disposed on the vehicle rear side of the front-side frame member81and extending toward the rear side, and a tubular connection member83connecting a rear portion of the front-side frame member81and a front portion of the rear-side frame member82. The front-side frame member81and the rear-side frame member82have hollow shapes, in other words, tubular shapes extending in the front-rear direction and may be formed of, for example, an extruded material. The front-side frame member81and the rear-side frame member82having hollow shapes are lightweight and high-stiffness members. Vertical cross-sections of the front-side frame member81and the rear-side frame member82in the vehicle width direction have rectangular shapes, and thus the front-side frame member81and the rear-side frame member82each include an upper wall portion and a lower wall portion extending in the right-left direction and right and left sidewall portions extending in the up-down direction. Note that the cross-sectional shapes of the front-side frame member81and the rear-side frame member82are not limited to rectangular shapes but may be pentagonal shapes or higher polygonal shapes or may be circular shapes or elliptical shapes.

The dimension of the rear-side frame member82in the longitudinal direction is set to be longer than the dimension of the front-side frame member81in the longitudinal direction. Accordingly, a connection part between the front-side frame member81and the rear-side frame member82is positioned on the front side of a front-rear direction central portion of the occupant space R1. Note that the center frame80is not limited to the two-division structure of the front-side frame member81and the rear-side frame member82but may be formed as one member a front portion to a rear portion or may have a three-division structure.

The front-side frame member81is tilted at a first tilt angle relative to a horizontal plane and extends straight. The rear-side frame member82is tilted at a second tilt angle smaller than the first tilt angle relative to the horizontal plane and extends straight. Since the rear-side frame member82is tilted at a tilt angle different from that of the front-side frame member81, the bend portion80A that bends downward is formed at the connection part between the front-side frame member81and the rear-side frame member82. In the present embodiment, the rear-side frame member82is arranged at a downward tilt toward the rear side. Note that the front-side frame member81and the rear-side frame member82may have the same tilt angle. In this case, no bend portion80A is formed.

As illustrated inFIG.4, the center frame80also includes a left-side frame member84A and a right-side frame member84B constituting the front portion of the center frame80, and accordingly, has a shape bifurcated in the right-left direction. The left-side frame member84A and the right-side frame member84B are provided at an interval from each other in the right-left direction. A rear portion of the left-side frame member84A is fixed to a left-side surface of a front-rear direction intermediate portion of the front-side frame member81. The left-side frame member84A is tilted from a fixation part to the front-side frame member81toward the front side in a plan view such that the left-side frame member84A is positioned farther on the left side at a position farther on the front side. A front portion of the left-side frame member84A is connected to a part of the dash panel50higher than and away from the occupant-space-side floor panel41. A rear portion of the left-side front frame54A is connected to the front portion of the left-side frame member84A.

A rear portion of the right-side frame member84B is fixed to a right-side surface of the front-rear direction intermediate portion of the front-side frame member81. The right-side frame member84B is tilted from a fixation part to the front-side frame member81toward the front side in a plan view such that the right-side frame member84B is positioned farther on the right side at a position farther on the front side. A front portion of the right-side frame member84B is connected to the part of the dash panel50higher than and away from the occupant-space-side floor panel41. A rear portion of the right-side front frame54B (illustrated inFIG.4) is connected to the front portion of the right-side frame member84B.

The upper-portion structural body3includes first to third connection members101to103. The first to third connection members101to103are members for connecting the center frame80to the occupant-space-side floor panel41, each member extending upward from the occupant-space-side floor panel41and having an upper portion fixed to the center frame80. The first connection member101is disposed farthest on the front side in the occupant space R1, and the first connection member101is separated on the rear side from the dash panel50. A lower portion of the first connection member101is fixed to a site separated on the rear side from the dash panel50on the occupant-space-side floor panel41, and an upper portion of the first connection member101is fixed to a site separated on the rear side from the dash panel50on the center frame80.

As illustrated in, for example,FIG.3, the second connection member102is separately disposed on the rear side of the first connection member101. The lower portion of the first connection member101and a lower portion of the second connection member102are fixed to sites separated from each other in the front-rear direction on the occupant-space-side floor panel41. The upper portion of the first connection member101and an upper portion of the second connection member102are fixed to sites separated from each other in the front-rear direction of the center frame80.

As illustrated inFIG.3, the first connection member101includes a left-side member (left-side connection member)101A and a right-side member (right-side connection member)101B. Lower portions of the left-side member101A and the right-side member101B are fixed to the front-portion cross member44A. The left-side member101A extends at a tilt in a front view such that the left-side member101A is positioned farther on the left side at a position farther on the upper side from the front-portion cross member44A. An upper portion of the left-side member101A is fixed to the front portion of the left-side frame member84A of the center frame80.

The right-side member101B extends at a tilt in a front view such that the right-side member101B is positioned farther on the right side at a position farther on the upper side from the front-portion cross member44A. An upper portion of the right-side member101B is fixed to the front portion of the right-side frame member84B of the center frame80. Since the front portion of the left-side frame member84A and the front portion of the right-side frame member84B are separated from each other in the right-left direction, most parts of the left-side member101A and the right-side member101B except for the lower portions thereof are separated from each other in the right-left direction, and accordingly, the interval between the left-side member101A and the right-side member101B in the right-left direction is larger at a position farther on the upper side.

A lower portion of the second connection member102is fixed to the intermediate cross member44B. The upper portion of the second connection member102is fixed to the bend portion80A of the center frame80. Accordingly, the second connection member102extends from the bend portion80A of the center frame80toward the occupant-space-side floor panel41.

A lower portion of the third connection member103is fixed to the recessed-portion front-side cross member44C. The recessed-portion front-side cross member44C is disposed directly above the second rear-portion central member18, and the right-left direction central portion of the recessed-portion front-side cross member44C is fixed to a front portion of the second rear-portion central member18. Accordingly, the lower portion of the third connection member103is fixed to part of the occupant-space-side floor panel41, which corresponds to the second rear-portion central member18. An upper portion of the third connection member103is fixed to the lower wall portion of the rear-side frame member82of the center frame80.

Load Path at Collision

Subsequently, a case in which the automobile1undergoes front collision is assumed. At front collision of the automobile1, an impact load is input from the bumper reinforcement140to the left-side crush can53A and the right-side crush can53B. The impact load input to the left-side crush can53A and the right-side crush can53B is transferred to the right and left front-wheel suspension support members51A and51B.

Since the right and left front-wheel suspension support members51A and51B are connected to the dash panel50, the center frame80, and the front support frames20, the impact load input to the right and left front-wheel suspension support members51A and51B is transferred to the dash panel50, the center frame80, and the front support frames20and absorbed. In addition, since the right and left front-wheel suspension support members51A and51B are also connected to the right and left side sills60and60, the impact load input to the right and left front-wheel suspension support members51A and51B is also transferred to the right and left side sills60and60and absorbed.

Furthermore, since the front portion of the center frame80and the left-side front-wheel suspension support member51A are connected to each other through the left-side front frame54A and the front portion of the center frame80and the right-side front-wheel suspension support member51B are connected to each other through the right-side front frame54B, the impact load is also input to the center frame80and absorbed.

In addition, since a rear portion of each front support frame20is connected to the rack frame10included in the battery unit Y, the impact load input to the front support frame20is also transferred to the rack frame10and absorbed. In this case, since not only the left-side member11and the right-side member12extending in the front-rear direction but also the front-portion central member16and the first to third rear-portion central members17to19are provided extending in the front-rear direction in the rack frame10, the impact load can also be absorbed by these members11,12, and16to19. In addition, similarly to the front-portion central member16and the first to third rear-portion central members17to19, since the floor frame41cis provided extending in the front-rear direction inside the recessed portion41aof the occupant-space-side floor panel41, the impact load can be absorbed by the floor frame41cas well. A plurality of load paths are provided in this manner, and thus it is possible to maintain the occupant space R1at collision.

As described above, according to embodiments of the disclosure, since the battery non-housing portion202is provided below the occupant-space-side floor panel41, the occupant-space-side floor panel41can be lowered at the part corresponding to the battery non-housing portion202to expand a foot space for a front-seat passenger. Accordingly, comfort of a vehicle cabin improves.

Since no battery is housed in the battery non-housing portion202, vehicle-body stiffness potentially decreases at that part, but in the present embodiment, not only the front-portion central member16and the first to third rear-portion central members17to19extending in the front-rear direction are disposed below the occupant-space-side floor panel41but also the second rear-portion central member18disposed at the battery non-housing portion202is larger in width than the front-portion central member16and the third rear-portion central member19disposed at the battery housing portions200and201and has high strength, and accordingly, vehicle-body stiffness of the battery non-housing portion202can be increased, which improves vehicle safety.

Moreover, since the batteries FB and RB are housed in the front-side battery housing portion200and the rear-side battery housing portion201, respectively, the number of mounted batteries can be increased, and in this case, passenger comfort can be improved by using the battery non-housing portion202positioned between the front-side battery housing portion200and the rear-side battery housing portion201.

In addition, since the first harness204and the second harness205are disposed alongside each other in the vehicle width direction below the second rear-portion central member18having a larger width, the dimension in the up-down direction is shortened so that adverse influence on comfort is avoided, and both harnesses204and205can be collectively disposed.

As described above, a vehicle-body structure according to the present disclosure is applicable to, for example, an electric vehicle and other automobiles.

REFERENCE SIGNS LIST

1automobile10rack frame16front-portion central member (front-side first frame portion)17first rear-portion central member (front-side first frame portion)18second rear-portion central member (second frame portion)19third rear-portion central member (rear-side first frame portion)41occupant-space-side floor panel80center frame103third connection member200front-side battery housing portion201rear-side battery housing portion202battery non-housing portion204first harness205second harnessFB, RB batteryM traveling motor

The present disclosure is not limited to only the above-described embodiments, which are merely exemplary. It will be appreciated by those skilled in the art that the disclosed systems and/or methods can be embodied in other specific forms without departing from the spirit of the disclosure or essential characteristics thereof. The presently disclosed embodiments are therefore considered to be illustrative and not restrictive. The disclosure is not exhaustive and should not be interpreted as limiting the claimed invention to the specific disclosed embodiments. In view of the present disclosure, one of skill in the art will understand that modifications and variations are possible in light of the above teachings or may be acquired from practicing of the disclosure.

Reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” Moreover, where a phrase similar to “at least one of A, B, or C” is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.

No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f) unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The scope of the invention is indicated by the appended claims, rather than the foregoing description.