Patent ID: 12194828

DESCRIPTION OF EMBODIMENTS

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, front, rear, up, down, left, and right refer to an orientation relative to a forward movement direction of a vehicle unless otherwise specified. Further, an arrow FR indicating a forward direction with respect to the vehicle, an arrow UP indicating an upward direction with respect to the vehicle, and an arrow LH indicating a leftward direction with respect to the vehicle are shown at appropriate places in the drawing.

FIG.1is a perspective view of a vehicle body lower section near a rear portion of a vehicle1according to the present embodiment from an upper side obliquely to a front and left side.FIG.2is a cross-sectional view along line II-II ofFIG.1.

Reference sign10inFIG.1denotes a front floor panel disposed below a rider compartment. Reference sign11denotes a rear floor panel disposed behind the front floor panel10. Side sills12, which are skeleton frames extending in a front-rear direction of a vehicle body, are disposed on both left and right sides of a lower side of the rider compartment. The front floor panel10is installed between the left and right side sills12. A lower surface side of the front floor panel10is supported by a plurality of floor frames (not shown). A rear side frame30, which is a skeleton frame extending toward a rear side of the vehicle body, is coupled to an inner side of a rear region of each of the left and right side sills12of the vehicle body in a vehicle width direction. The rear floor panel11is installed between the left and right rear side frames30.

The front floor panel10, the rear floor panel11, the side sills12, the rear side frames30, and main constituent members of the vehicle body lower section, which will be described later, are mainly made of metal materials.

A floor tunnel15extending in the front-rear direction of the vehicle body is provided at a center of the front floor panel10in the vehicle width direction. The floor tunnel15is formed in a cross-sectional shape of substantially a U shape that opens downward, and the cross-sectional shape of substantially a U shape extends in the front-rear direction of the vehicle body. The floor tunnel15bulges upward with respect to a substantially flat base wall (a substantially horizontally extending bottom wall) of the front floor panel10.

FIG.3is a cross-sectional view along line ofFIG.1.FIG.4is a cross-sectional view along line IV-IV ofFIG.1.

As shown inFIGS.3and4, a rear edge portion of the front floor panel10is provided with a front cross member20extending in the vehicle width direction. The front cross member20is formed by joining a plurality of panel members22a,22b, and22cto a main cross panel21joined to a rear end portion of the front floor panel10. The front cross member20has a substantially rectangular closed cross section23, and the closed cross section23extends in the vehicle width direction. End portions of the front cross member20on an outer side in the vehicle width direction are coupled to the left and right side sills12corresponding thereto.

As shown inFIG.2, in the front cross member20, a height in a vertical direction of a center region in the vehicle width direction is lower than a height of each of left and right end regions. As can be seen from a comparison betweenFIGS.3and4, the left and right end regions of the front cross member20expand to a vehicle rear side with respect to a front-rear width of the center region of the front cross member20in the vehicle width direction. In each of the left and right end regions of the front cross member20, a portion expanding in the front-rear width is hereinafter referred to as a “widened portion20E.”

As shown inFIGS.3and4, the front cross member20has a front wall20fthat rises upward at a rear portion of the front floor panel10and an upper wall20uthat bends substantially at a right angle from an upper end portion of the front wall20fand extends to the vehicle rear side. The front wall20fand the upper wall20uare formed continuously over substantially the entire region of the front cross member20in the vehicle width direction. Therefore, a ridge Lc formed by a bent corner portion between the front wall20fand the upper wall20uextends over substantially the entire region of the front cross member20in the vehicle width direction. For convenience of explanation, in the ridge Lc, a portion formed in each of the left and right widened portions20E is hereinafter referred to as a “widened portion ridge Lce.”

Further, as shown inFIG.3, a front edge portion of the rear floor panel11is provided a rear cross member25extending in the vehicle width direction. The rear cross member25is formed by joining a rear edge portion of an intermediate floor panel31, which will be described later, to the front edge portion of the rear floor panel11. The rear cross member25has a substantially rectangular closed cross section26, and the closed cross section26extends in the vehicle width direction. End portions of the rear cross member25on the outer side in the vehicle width direction are coupled to the left and right rear side frames30corresponding thereto.

The above-described intermediate floor panel31is disposed between the front floor panel10and the rear floor panel11. The intermediate floor panel31constitutes the rear cross member25with its rear edge portion joined to the front edge portion of the rear floor panel11as described above. A front edge portion of the intermediate floor panel31is joined to the front cross member20. The intermediate floor panel31is connected to the front floor panel10via the front cross member20. A bottom wall portion31brecessed below each upper surface of the front cross member20and the rear cross member25is provided between the front edge portion and the rear edge portion of the intermediate floor panel31.

A battery32used for driving the vehicle and battery peripheral devices such as a control device (not shown) for electric power control are disposed on an upper surface side of the bottom wall portion31b. Further, end portions of the bottom wall portion31bon the outer side in the vehicle width direction are joined to the left and right side sills12corresponding thereto.

In the present embodiment, the front floor panel10, the intermediate floor panel31, and the rear floor panel11constitute a vehicle body floor, and the bottom wall portion31bof the intermediate floor panel31constitutes a battery housing portion.

A battery cover40made of a metal covers upper portions of the battery32and the battery peripheral devices housed in the bottom wall portion31b(the battery housing portion) of the intermediate floor panel31. The battery cover40is coupled to the front cross member20on the front side and the rear cross member25on the rear side by bolting or the like.

As shown inFIGS.1and3, the battery cover40includes a rear flange40rfthat is joined to the upper surface of the rear cross member25(the rear edge portion of the intermediate floor panel31), an upper wall40uthat inclines forward and upward from the rear flange40rfand then extends forward substantially horizontally, and a front wall40fthat bends downward and extends from a front end portion of the upper wall40u. The upper wall40ugently curves and bulges upward at a center in the vehicle width direction.

A rear seat (not shown) is fixedly installed above the upper wall40uof the battery cover40. For this reason, a load of the rear seat and a rider sitting on the rear seat acts on the upper wall40uof the battery cover40from above.

FIG.5is a perspective view showing a part ofFIG.1in an enlarged manner.

As shown inFIGS.1and5, in an end portion of the upper wall40uof the battery cover40on the outer side in the vehicle width direction, a side wall40sthat extends from the end portion toward the outer side in the vehicle width direction to incline downward and an end flange40efthat bends from a lower end of the side wall40stoward the outer side in the vehicle width direction and extends substantially horizontally are formed. The end flange40efis formed to be continuous with rear flange40rfof the battery cover40.

The front wall40fof the battery cover40is provided with extension portions40feconnected to both left and right sides on the outer side in the vehicle width direction. A center region of the front wall40fof the battery cover40in the vehicle width direction bends downward and extends from the front end portion of the upper wall40u. On the other hand, the left and right extension portions40feare bent downward and extend from the front end portions of the side walls40sextending obliquely downward from the end portions of the upper wall40uon the outer sides in the vehicle width direction and the front end portions of the end flanges40ef. Therefore, the front wall40fof the battery cover40has a substantially trapezoidal shape, when viewed from the front, in which a lower side is longer than an upper side.

The battery cover40has a front cover ridge Lf that extends from one end side to the other side in the vehicle width direction along an upper edge of the front wall40fincluding the left and right extension portions40fe. The front cover ridge Lf is continuous over a boundary portion between the center region of the front wall40fin the vehicle width direction and the upper wall40u, a boundary portion between the extension portion40feand the side wall40s, and a boundary portion between the extension portion40feand the end flange40ef.

A portion of the front cover ridge Lf positioned at the boundary portion between the extension portion40feand the side wall40sis hereinafter referred to as an inclined ridge portion Lfi. A portion positioned at the boundary portion between the extension portion40feand the end flange40efis referred to as an end ridge portion Lfe.

The battery cover40of the present embodiment is formed by joining a plurality of metal panels. However, the battery cover40can also be formed from a single metal panel.

Here, in the end portion of the battery cover40on the outer side in the vehicle width direction, the end flange40efoverlaps over upper surfaces of the corresponding left and right widened portions20E of the front cross member20and the rear side frame30, and the extension portion40feof the front wall40foverlaps a front surface of the widened portion20E (a front surface of the front wall201). At this time, the end portion of the battery cover40on the outer side in the vehicle width direction overlaps the widened portion20E such that the front cover ridge Lf (the end ridge portion Lfe) of the battery cover40is continuous with the widened portion ridge Lce of the widened portion20E.

In the end portion of the battery cover40on the outer side in the vehicle width direction, the extension portion40feof the front wall40fis fixed to the front surface of the widened portion20E with a bolt B1, and the end flange40efis fixed to the upper surface of the widened portion20E with a bolt B2. Hereinafter, the bolt B1for fixing the extension portion40feto the front surface of the widened portion20E is referred to as a first bolt B1, and the bolt B2for fixing the end flange40efto the upper surface of the widened portion20E is referred to as a second bolt B2.

A center region of the front wall40fof the battery cover40overlaps the front surface of the front wall20fof the front cross member20and is fixed to the front wall20fof the front cross member20with a plurality of bolts (reference signs omitted).

In the present embodiment, the left and right end flanges40efand the left and right extension portions40feof the front wall40fin the vehicle width direction constitute an outer connecting portion50of the battery cover40. Further, a fixing portion of the battery cover40with the first bolt B1constitutes a first fixing point in the outer connecting portion50. A fixing portion of the battery cover40with the second bolt B2constitutes a second fixing point in the outer connecting portion50. The first fixing point and the second fixing point are provided on two walls (the extension portion40feof the front wall40fand the end flange40ef) that intersect with each other with the front cover ridge Lf interposed therebetween.

The first bolt B1fixes the extension portion40feto the front wall20fof the widened portion20E in the front-rear direction at a position below the inclined ridge portion Lfi (a position overlapping the inclined ridge portion Lfi in the vehicle width direction) of the extension portion40feof the front wall40fof the battery cover40. The second bolt B2fixes the end flange40efto the upper wall20uof the widened portion20E in the vertical direction at the end flange40efof the battery cover40positioned on the outer side from the inclined ridge portion Lfi in the vehicle width direction. Further, the second bolt B2fixes the end flange40efto the widened portion20E at a position close to the end ridge portion Lfe near the front end portion of the end flange40ef.

Two reinforcing beads55aand55bare formed on the end flange40efand the side wall40sof the battery cover40to straddle the both. The reinforcing beads55aand55bare disposed on the vehicle rear side from the fixing portion (the second fixing point) of the second bolt B2on the end flange40ef. The reinforcing beads55aand55bare disposed to be spaced apart from each other in the front-rear direction of the vehicle body.

Each of the reinforcing beads55aand55bis formed in a substantially triangular shape in front view, with an apex angle positioned on an upper side of the side wall40sand opposite sides positioned on the end flange40ef. Side portions of each of the reinforcing beads55aand55bbulge upward on a side surface of the side wall40s, and lower ends of the bulging portions are connected to an upper surface of the end flange40ef. The reinforcing beads55aand55bincrease rigidity of the side wall40swith a truss structure bulging from the side surface of the side wall40s.

Further, the two reinforcing beads55aand55bare not of the same size, and the reinforcing bead55adisposed on a front side is formed larger than the reinforcing bead55bdisposed on a rear side. In other words, the reinforcing bead55aon the front side is set larger than the reinforcing bead55bon the rear side in terms of a bulging height and a front-rear width.

Further, the two reinforcing beads55aand55bare disposed on the inner side from the fixing portion (the second fixing point) of the second bolt B2provided on the end flange40efin the vehicle width direction. The fixing portion (the second fixing point) of the second bolt B2provided on the end flange40efis disposed between the end ridge portion Lfe (the front cover ridge Lf) on a front end side of the end flange40efand the reinforcing bead55aon the front side.

The battery cover40is further provided with a side ridge Ls that extends in a front-rear direction of the vehicle at a boundary portion between an upper end portion of the side wall40sand the upper wall40u. The side ridge Ls intersects with the front cover ridge Lf on a front end side and extends to the vicinity of the rear cross member25on a rear end side. A rear edge portion (the rear flange40rf) of the battery cover40is fixed to the rear cross member25with a bolt B3at a position on the inner side from the side ridge Ls in the vehicle width direction. The bolt B3fixes the rear edge portion of the battery cover40to the rear cross member25in the vertical direction.

In the present embodiment, the fixing portion of the bolt B3constitutes a rear-side fixing point.

As described above, in the vehicle body lower section structure of the present embodiment, the end portion of the front cross member20on the outer side in the vehicle width direction is provided with the widened portion20E, and the outer connecting portion50of the battery cover40made of a metal is connected to the widened portion20E. For this reason, when an impact load is input from one side of the vehicle1to one side sill12, the impact load input from the one side sill12to one widened portion20E of the front cross member20is transmitted to the battery cover40made of a metal through one outer connecting portion50. Further, the impact load transmitted to the battery cover40is transmitted to the other widened portion20E of the front cross member20through the other outer connecting portion50and transmitted to the other side sill12through the other widened portion20E.

Therefore, in the vehicle body lower section structure of the present embodiment, it is possible to perform load transmission via the battery cover40made of a metal in parallel with load transmission of the front cross member20when the impact load is input from a side portion of the vehicle. Therefore, in a case where the vehicle body lower section structure of the present embodiment is adopted, it is possible to reliably protect the battery32and the battery peripheral devices while reducing a size and a weight of the reinforcing structure around the battery housing portion.

Further, in the vehicle body lower section structure of the present embodiment, the height in the vertical direction of the center region of the front cross member20in the vehicle width direction is set to be low with respect to the widened portion20E at the end portion. For this reason, a cross section of the center region of the front cross member20in the vehicle width direction can be made smaller, and a capacity of the housing portion for the battery32can be increased. In addition, since the height of the upper surface of the center region of the front cross member20in the vehicle width direction is low, a harness such as an electric wire extending from the housing portion of the battery32into the floor tunnel15can be easily routed over the upper surface of the front cross member20.

Here, in the front cross member20, the height in the vertical direction and the front-rear width decrease from the widened portion20E on the outer side in the vehicle width direction toward the center region, and thus stress is likely to concentrate on a portion where a cross-sectional shape changes abruptly. However, in the vehicle body lower section structure of the present embodiment, the widened portion20E of the front cross member20is connected to the battery cover40made of a metal through the outer connecting portion50, and thus it is possible to relieve the concentration of the stress on the portion where the cross-sectional shape of the front cross member20changes. For this reason, in a case where the present configuration is adopted, the impact load input from one side of the vehicle1is efficiently transmitted to the other side of the vehicle1, and the battery32housed in the battery housing portion can be more reliably protected.

In addition, in the vehicle body lower section structure of the present embodiment, the front cover ridge Lf extending in the vehicle width direction is provided at an upper edge portion of the front wall40fof the battery cover40, and the widened portion ridge Lce extending in the vehicle width direction is provided at an upper edge portion of the front wall20fof the widened portion20E of the front cross member20. Therefore, the end portion of the battery cover40on the outer side in the vehicle width direction overlaps the widened portion20E such that the front cover ridge Lf is continuous with the widened portion ridge Lce. For this reason, when the impact load is input from one side of the vehicle1to one side sill12, the impact load is transmitted to the battery cover40made of a metal through the widened portion ridge Lce of the widened portion20E of the front cross member20and the front cover ridge Lf of the battery cover40. Therefore, the impact load from a lateral side can be efficiently transmitted to the other side of the vehicle1through the continuous high-rigidity ridges of the widened portion20E and the battery cover40.

Therefore, in a case where the present configuration is adopted, it is possible to more reliably protect the battery32and the battery peripheral devices housed in the battery housing portion while preventing the front cross member20from increasing in size.

Further, in the vehicle body lower section structure of the present embodiment, the outer connecting portion50of the battery cover40includes the extension portion40feand the end flange40efthat intersect with each other with the front cover ridge Lf interposed therebetween, and the extension portion40feand the end flange40efare provided with the fixing portion (the fixing point) of the first bolt B1and the fixing portion (the fixing point) of the second bolt B2, respectively. For this reason, the impact load input to the outer connecting portion50from the widened portion20E of the front cross member20through the fixing point of the first bolt B1and the fixing portion of the second bolt B2can be efficiently transmitted to the front cover ridge Lf of the battery cover40.

Therefore, in a case where the present configuration is adopted, it is possible to further curb deformation and damage to the battery32and the peripheral portions thereof when the impact load is input from the lateral side of the vehicle1.

Furthermore, in the vehicle body lower section structure of the present embodiment, the fixing portion of the first bolt B1fixes one wall (the extension portion40fe) of the outer connecting portion50to the front wall20fof the widened portion20E in the front-rear direction, and the fixing portion of the second bolt B2fixes the other wall (the end flange40ef) of the outer connecting portion50to the upper wall20uof the widened portion20E in the vertical direction. For this reason, the two walls (the extension portion40feand the end flange40ef) of the outer connecting portion50which intersect with each other are firmly fixed to the widened portion20E with the first bolt B1and the second bolt B2in the front-rear direction and in the vertical direction. Therefore, in a case where the present configuration is adopted, it is possible to prevent the battery cover40from being rotationally deformed or torsionally deformed about an axis in the vehicle width direction when the impact load is input from the lateral side of the vehicle.

In addition, in the vehicle body lower section structure of the present embodiment, the outer connecting portion50of the battery cover40is fixed to the upper wall20uof the widened portion20E with the second bolt B2in the vertical direction, and thus a seat load acting on the upper wall40uof the battery cover40from a rear seat can be efficiently transmitted to the widened portion20E of the front cross member20. Therefore, in a case where the present configuration is adopted, it is possible to increase support rigidity of the rear seat and curb wobbling of the rear seat.

In addition, in the vehicle body lower section structure of the present embodiment, the fixing portion (the first fixing point) of the first bolt B1of the outer connecting portion50is disposed at a position overlapping the inclined ridge portion Lfi of the front cover ridge Lf in the vehicle width direction, and the fixing portion (the second fixing point) of the second bolt B2is disposed on the outer side from the inclined ridge portion Lfi of the front cover ridge Lf in the vehicle width direction. For this reason, the impact load input to the outer connecting portion50from the lateral side of the vehicle through the fixing portion (the second fixing point) of the second bolt B2can be distributed over a wide range of the inclined ridge portion Lfi and the side wall40sof the battery cover40. Therefore, in a case where the present configuration is employed, it is possible to curb deformation (buckling) of the inclined ridge portion Lfi of the battery cover40due to excessive concentration of the impact load on the inclined ridge portion Lfi.

Furthermore, in the vehicle body lower section structure of the present embodiment, the outer connecting portion50of the battery cover40is provided with the reinforcing beads55aand55bextending over from the end flange40efto the side wall40s. For this reason, in a case where the impact load is input from the lateral side of the vehicle1, the impact load can be efficiently transmitted to a side of the upper wall40uof the battery cover40via the end flange40efand the side wall40sin a state where the deformation of the side wall40sof the battery cover40is curbed by the reinforcing beads55aand55b.

Further, in the vehicle body lower section structure of the present embodiment, the reinforcing beads55aand55bare disposed on the inner side from the fixing portion (the second fixing point) of the second bolt B2provided on the end flange40efof the outer connecting portion50in the vehicle width direction. For this reason, the reinforcing beads55aand55bare disposed on the inner side from the fixing portion (the second fixing point) of the second bolt B2on the end flange40efto which the load is input in the vehicle width direction in an initial state when the impact load is input from the lateral side of the vehicle1. Therefore, in a case where the present configuration is adopted, it is possible to prevent the side wall40sof the battery cover40from being deformed when the impact load is input from the lateral side of the vehicle1, and it is possible to more reliably protect the battery32and the battery peripheral devices from the impact load.

In addition, in the vehicle body lower section structure of the present embodiment, the fixing portion (the second fixing point) of the second bolt B2on the end flange40efis disposed between the end ridge portion Lfe (the front cover ridge Lf) of the battery cover40and the reinforcing bead55a. For this reason, the impact load input from the lateral side of the vehicle1can be distributed to the front cover ridge Lf and the reinforcing bead55avia the fixing portion (the second fixing point) of the second bolt B2on the end flange40efto be transmitted to a side of the upper wall40uof the battery cover40. Therefore, in a case where the present configuration is adopted, it is possible to further curb the deformation of the battery cover40due to the impact load.

Further, in the vehicle body lower section structure of the present embodiment, the reinforcing beads55aand55bare disposed side by side in the front-rear direction on the vehicle rear side from the fixing portion (the second fixing point) of the second bolt B2on the end flange40ef. Each of the reinforcing beads55aand55bis formed in a substantially triangular shape with an apex angle positioned on an upper side of the side wall40sin a front view, and the reinforcing bead55aon a side close to the fixing portion (the second fixing point) of the second bolt B2is formed larger than the reinforcing bead55bon a side away from the fixing portion. For this reason, the impact load input to the end flange40efof the battery cover40can be efficiently transmitted to a side of the upper wall40uof the battery cover40via the two reinforcing beads55aand55bhaving a truss structure. In addition, since the reinforcing bead55aon a side close to the fixing portion (the second fixing point) of the second bolt B2is formed larger than the reinforcing bead55bon a side away from the fixing portion, the impact load input to the fixing portion (the second fixing point) of the second bolt B2can be efficiently transmitted to a side of the upper wall40uof the battery cover40in the vicinity of the front cover ridge Lf.

Furthermore, in the vehicle body lower section structure of the present embodiment, the boundary portion between the side wall40sand the upper wall40uof the battery cover40is provided with a side ridge Ls extending from the end portion (the front cover ridge Lf) on a side of the front wall to the vicinity of the rear cross member25. Therefore, the rear edge portion of the battery cover40is fixed to the rear cross member25with the bolt B3at a position on the inner side from the rear end portion of the side ridge Ls in the vehicle width direction. For this reason, when the impact load is input from one side of the vehicle1to one widened portion20E of the front cross member20, the impact load is transmitted to the other side in the vehicle width direction along the front cover ridge Lf of the front cross member20. The impact load on the one side is transmitted to a side of the rear edge portion of the battery cover40through the side ridge Ls that branches off from the front cover ridge Lf to extend to the vehicle rear side and is received by the rear cross member25through the fixing portion of the bolt B3of the rear edge portion.

Therefore, in a case where the present configuration is adopted, the impact load input from one side of the vehicle1to the front cover ridge Lf of the front cross member20is also efficiently distributed to a side of the rear cross member25, and thus excessive concentration of the load on the front cross member20can be avoided. Therefore, in a case where the present configuration is adopted, it is possible to curb the deformation of the front cross member20, and thus it is possible to more reliably protect the battery32and the battery peripheral devices.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist thereof.

For example, in the above embodiment, the battery housing portion and the battery cover are disposed in the rear portion of the vehicle compartment, but the battery housing portion and the battery cover may be disposed in a portion other than the rear portion of the vehicle compartment.