JP2018202887A - Vehicular lower structure - Google Patents

Abstract

To provide a vehicular lower structure capable of preventing a battery cross member from falling down in a back-and-forth direction when load in the back-and-forth direction is input to the battery cross member from a vehicle body cross member, and of maintaining a high support rigidity of the vehicle body cross member.SOLUTION: A lower structure includes: a pair of side sills; a battery case 28; a battery cross member 45; and a vehicle body cross member. The battery cross member 45 is formed in a cross-sectional shape that is in an inverted T-shape which includes: a member body 37 standing upright and having an upper part coupled to the vehicle body cross member via a fastening member; a forward projecting seat 38 that projects forwardly from a lower edge of the member body 37; and a backward projecting seat 39 that projects backwardly from the lower edge of the member body 37. The forward projecting seat 38 and the backward projecting seat 39 are coupled to a bottom wall of th battery case 28.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a lower structure of a vehicle.

  As a lower structure of a vehicle, a structure in which a battery case that houses a plurality of batteries is installed between side sills on the left and right sides of the vehicle body is known (see, for example, Patent Documents 1 and 2).

  In the lower structure of a vehicle described in Patent Document 1, battery cases disposed below the floor panel are installed on left and right side sills. A battery cross member extending along the vehicle width direction is coupled to the inside of the battery case. The battery cross member has a vertically long rectangular cross section extending substantially along the vehicle width direction and is coupled to a peripheral wall and a bottom wall of the battery case. The battery cross member functions to transmit the input load to the inner side in the vehicle width direction while securing a space portion on the inner side in the vehicle width direction when an impact load is input to the side sill from the side.

  Further, in the vehicle lower structure described in Patent Document 1, a vehicle body-side cross member extending substantially along the vehicle width direction on the floor panel is disposed above the battery cross member. The vehicle body side cross member has both ends in the vehicle width direction laid on the left and right side sills, and a central region in the vehicle width direction is connected to the lower battery cross member via a fastening member. A seat belt anchor for supporting the anchor belt of the seat belt device is fixed to the vehicle body side cross member.

US Pat. No. 8,336,658

  In the lower structure of the vehicle described in Patent Document 1, the battery cross member is formed in a vertically long rectangular cross-sectional shape, and the lower end thereof is fixed to the upper surface of the bottom wall of the battery case by welding. For this reason, when a large load in the front-rear direction is input to the vehicle body side cross member through the seat bell anchor and the load is transmitted to the upper portion of the battery cross member via the fastening member, the battery cross member is caused by the moment acting on the battery cross member. There is concern about members falling back and forth.

  Accordingly, the present invention provides a vehicle capable of suppressing the tilt of the battery cross member in the front-rear direction and inputting the load in the front-rear direction from the vehicle body-side cross member to the battery cross member and maintaining the support rigidity of the vehicle body-side cross member high. It is intended to provide a substructure.

The vehicle lower structure according to the present invention employs the following configuration in order to solve the above problems.
That is, the vehicle lower structure according to the present invention is disposed on the left and right sides of the vehicle body, and has a pair of side sills (for example, the side sill 14 of the embodiment) extending substantially along the longitudinal direction of the vehicle body, A battery case (for example, battery case 28 of the embodiment) in which the battery is housed and the left and right edges are installed on the pair of side sills, and provided in the battery case, extends substantially along the vehicle width direction. A battery cross member (for example, the battery cross member 45 of the embodiment) that extends substantially along the vehicle width direction on the upper side of the battery cross member, and both end portions are constructed on the pair of side sills and an intermediate region A vehicle body side cross member (for example, the embodiment) is coupled to the battery cross member by a fastening member (for example, the stud bolt 46 of the embodiment). The battery cross member is erected upward, and the upper portion of the battery cross member is coupled to the vehicle body side cross member by the fastening member (for example, the member main body portion 37 of the embodiment). ), A front overhanging seat projecting forward from the lower edge of the member main body (for example, the front overhanging seat 41 of the embodiment), and a rear overhanging seat projecting rearward from the lower edge of the member main body (for example, implementation) A rear projecting seat 42) having an inverted T-shaped cross section, and the front projecting seat and the rear projecting seat are coupled to the bottom wall of the battery case (for example, the bottom wall 28Aa of the embodiment). It is characterized by being.

  With the above configuration, when a longitudinal load is input to the vehicle body side cross member, the load is input to the upper portion of the member main body portion of the battery cross member via the fastening member. As a result, a moment in a direction that tilts forward and backward acts on the member main body, but a front overhanging seat and a rear overhanging seat extend from the front and back of the member main body, and these overhanging seats are coupled to the bottom wall of the battery case. Has been. For this reason, the member body is prevented from falling by the front overhanging seat and the rear overhanging seat. As a result, the vehicle body side cross member is supported with high rigidity via the member main body and the fastening member.

  The front projecting seat and the rear projecting seat are disposed on the upper surface side of the bottom wall of the battery case, and a lower surface reinforcing member (for example, the lower surface reinforcing member 61 of the embodiment) is disposed on the lower surface side of the bottom wall, The front projecting seat and the rear projecting seat may be coupled to the lower surface reinforcing member with the bottom wall interposed therebetween.

  In this case, since the front overhang seat and the back overhang seat of the battery cross member are integrated with the bottom wall of the battery case together with the lower surface reinforcing member, it is possible to more firmly suppress the front-rear tilting of the member main body portion of the battery cross member. Can do. Moreover, when this structure is employ | adopted, it becomes possible to comprise each member couple | bonded by the press-molding goods which can be manufactured at low cost, and to fix each member by welding.

  The lower surface reinforcing member may be constituted by a plate-like member having a substantially wave-shaped cross section extending substantially along the vehicle width direction.

  In this case, since the substantially wave-shaped cross section of the plate-shaped member that is the lower surface reinforcing member extends substantially along the vehicle width direction on the lower surface side of the bottom wall of the battery case, the plate-shaped lower surface reinforcing member The rigidity of the bottom wall can be increased efficiently.

  The battery case has a case side wall (for example, the case side wall 50 in the embodiment) that rises upward from the left and right ends of the bottom wall, and extends substantially along the vehicle body longitudinal direction outside the case side wall. A case frame (for example, the case frame 52 of the embodiment) is coupled, and the case frame is disposed on the lower surface of the bottom wall of the battery case to constitute the lower surface reinforcing member (for example, an extension of the embodiment). The front projecting seat and the rear projecting seat may be coupled to the extension piece with the bottom wall interposed therebetween.

  In this case, the extension piece provided on the case frame is disposed on the lower surface of the bottom wall of the battery case, and the front overhanging seat and the rear overhanging seat of the battery cross member are integrated with the bottom wall and the extension piece of the battery case. become. Thereby, the front-and-back falling of the member main body part of a battery cross member is suppressed more firmly.

  The member main body of the battery cross member includes an upper wall (for example, the upper wall 37u of the embodiment) and a front wall (for example, the front wall 37f of the embodiment) that extends downward from the front portion of the upper wall. A rear wall extending downward from the rear portion of the upper wall (for example, the rear wall 37r of the embodiment), and in the vicinity of the fixing portion of the fastening member of the member main body portion, the member main body portion A partition member (for example, the first partition member 58 and the second partition member 59 in the embodiment) that restrains the three surfaces of the upper wall, the front wall, and the rear wall may be combined.

  In this case, since the cross-sectional rigidity in the vicinity of the fixing portion of the fastening member of the member main body is enhanced by the partition member, the cross-sectional deformation in the vicinity of the fixing portion of the fastening member can be efficiently suppressed. Therefore, even when the thickness of the member main body must be reduced for weight reduction, the fastening member is prevented from tilting and sinking, and the floor cross member is supported by the battery cross member with high rigidity. be able to.

  A floor panel (for example, the floor panel 16 of the embodiment) is disposed above the battery case, and the vehicle body side cross member is joined to the upper surface of the floor panel so that the vehicle width is between the floor panel and the vehicle. A cross plate having a substantially hat-shaped cross section (for example, the cross plate 65 of the embodiment) having a closed cross section extending substantially along the direction and having both ends in the vehicle width direction spanning the pair of side sills, A gusset having a substantially hat-shaped cross section that is laid on the lower surface of the end region in the vehicle width direction of the floor panel and the side surface of the side sill and forms a closed cross section extending substantially along the vehicle width direction between the floor panel A plate (for example, the gusset plate 66 of the embodiment), and the end region in the vehicle width direction of the cross plate and the gusset plate face outward in the vehicle width direction. A bracket (for example, the bracket 48 of the embodiment) that also serves as a cross-sectional reinforcing portion is attached inside the region near the center of the cross plate in the vehicle width direction, and the bracket is attached by the fastening member. You may make it couple | bond with the said member main-body part of the said battery cross member.

  In this case, the end region in the vehicle width direction of the cross plate and the gusset plate are formed so as to incline downward toward the outside in the vehicle width direction, so that the closed cross section of the central region formed by the floor panel and the cross plate Then, the inclined closed cross section of the end region formed by the cross plate and the gusset plate is continuous. For this reason, the left and right side sills can be connected by a substantially constant continuous closed cross section of the vehicle body side cross member, while the central region of the vehicle body side cross member is raised upward with respect to the side sill. In addition, when this configuration is adopted, since the center region of the vehicle body side cross member is lifted upward with respect to the side sill, the battery case disposed below the center region of the vehicle body side cross member is directed upward. Can be positioned. Therefore, the ground clearance below the battery case can be easily secured. In addition, the cross section of the central region of the cross plate is reinforced by a bracket that also serves as a cross-section reinforcing portion, and the bracket is coupled to the battery cross member by a fastening member. For this reason, when a load is input to the vehicle body side cross member, the input load can be supported by the battery cross member in a state in which the cross-sectional deformation of the cross plate is suppressed.

  In the battery case, the battery and the battery cross member are disposed inside, and a case main body (for example, the case main body 28A of the embodiment) that opens upward, and a case cover that closes the opening of the case main body (for example, implementation) The fastening member is a stud bolt (for example, the stud bolt 46 of the embodiment) whose both ends are fastened to the bracket and the battery cross member, and the body of the stud bolt A part (for example, body part 46a of an embodiment) is held by a penetration hole (for example, penetration hole 57 of an embodiment) of the case cover via an elastic seal member (for example, elastic seal member 56 of an embodiment). You may do it.

In this case, since the body portion of the stud bolt is held in the through hole of the case cover via the elastic seal member, the position of the screw portion protruding above the case cover when the stud bolt and the vehicle body side cross member are fastened and fixed. The direction can be fine-tuned. For this reason, when this configuration is adopted, the workability of fastening the vehicle body side cross member to the stud bolt is improved. Further, since the through hole of the case cover is closed by the elastic seal member, it is possible to prevent water from entering the battery case through the through hole. In this case, the vibration of the case cover can be further suppressed by the elastic seal member.
Further, when the upper surface of the elastic seal member is brought into contact with the lower surface of the peripheral area of the through hole of the floor panel, it is possible to prevent water from entering the vehicle interior through the through hole of the floor panel. Further, in this case, the vibration of the floor panel can be suppressed by the elastic seal member.

  An attachment frame (for example, the attachment frame 53 of the embodiment) for connecting the case frame to the lower surface of the side sill is coupled to the case frame, and the attachment frame is overlaid on the lower surface of the extension piece of the case frame. A frame extension piece (for example, the frame extension piece 53a of the embodiment) may be extended, and the frame extension piece may be coupled to the bottom wall of the battery case together with the extension piece.

  In this case, since the frame extension piece of the mounting frame and the extension wall of the case frame are coupled with the bottom wall of the battery case in a three-layered manner, the coupling between the mounting frame and the case frame can be further strengthened, and the battery case The rigidity of the bottom wall can be increased.

  The member main body of the battery cross member includes an upper wall (for example, the upper wall 37u of the embodiment) and a front wall (for example, the front wall 37f of the embodiment) that extends downward from the front portion of the upper wall. A rear wall that extends downward from the rear portion of the upper wall (for example, the rear wall 37r of the embodiment), and the member main body portion includes the upper wall, the front wall, and the rear wall. A reinforcing plate having a substantially U-shaped cross section (for example, the reinforcing plate 20 of the embodiment) may be arranged.

  In this case, the rigidity of the member main body to which the fastening member is fixed can be easily increased with a simple configuration. Further, the reinforcing plate can be formed by a press-molded product that can be manufactured at low cost. For this reason, reduction of product cost can be aimed at.

  The front overhanging seat and the rear overhanging seat are provided with a pedestal portion (for example, the pedestal portion 23 of the embodiment) whose upper surface protrudes upward and whose lower surface communicates with the internal space of the member main body and whose upper surface is substantially flat. May be.

  In this case, the upper surface of each pedestal portion provided on the front overhanging seat and the rear overhanging seat can be used as a battery support portion or the like. In addition, the pedestal that stands upward allows the lower surfaces of the front and rear overhanging seats to communicate widely with the internal space of the member main body. It becomes possible to spread easily to every corner of the interior.

  According to the present invention, the front projecting seat and the rear projecting seat are extended from the lower edge of the member main body of the battery cross member, and these front projecting seat and rear projecting seat are coupled to the bottom wall of the battery case. When a load in the front-rear direction is input from the vehicle body-side cross member to the battery cross member through the fastening member, the battery cross member can be prevented from falling in the front-rear direction. Therefore, according to the present invention, the support rigidity for the vehicle body side cross member can be increased.

It is a perspective view of the lower structure of vehicles of one embodiment of the present invention. It is the top view which removed a part component of the lower structure of vehicles of one embodiment of the present invention. It is sectional drawing which follows the III-III line | wire of FIG. 2 of the lower structure of the vehicle of one Embodiment of this invention. It is sectional drawing which follows the IV-IV line of FIG. 3 of the lower structure of the vehicle of one Embodiment of this invention. It is the perspective view which made the partial cross section in the part in alignment with the VV line of FIG. 3 of the lower structure of the vehicle of one Embodiment of this invention. 1 is a perspective view of a part of a vehicle lower structure according to an embodiment of the present invention. It is the perspective view which made the partial cross section in the part in alignment with the VII-VII line of FIG. 2 of the lower structure of the vehicle of one Embodiment of this invention. It is the perspective view which made the partial cross section in the part in alignment with the VII-VII line of FIG. 2 of the lower structure of the vehicle of one Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawing, the arrow FR indicates the front of the vehicle, the arrow UP indicates the upper side of the vehicle, and the arrow LH indicates the left side of the vehicle.

FIG. 1 is a view of a skeleton portion of a vehicle 10 according to the present embodiment as viewed from diagonally upward at the rear left, and FIG. 2 is a view of a lower structure 12 of the vehicle 10 as viewed from above. FIG. 3 is a cross-sectional view of the lower structure 12 taken along line III-III in FIG.
The lower structure 12 is a structure located on the lower side of the vehicle 10 and includes a pair of side sills 14 that are disposed on the left and right side portions on the lower end side of the vehicle body and extend substantially along the front-rear direction of the vehicle body. Is the body.
The lower structure 12 includes a pair of side sills 14, a floor panel 16 in which both ends in the vehicle width direction are installed on the left and right side sills 14, and a plurality of floor cross members 34 disposed on the upper surface side of the floor panel 16. 35 and 36 (vehicle body side cross members), a battery case 28 (see FIG. 3) installed on the left and right side sills 14 below the floor panel 16, and a plurality of battery cross members provided inside the battery case 28 45. In the case of the present embodiment, the front and rear floor cross members 34 and 35 are each provided with a front and rear installation portion of a driver seat 31 and a passenger seat 32 installed in the vehicle interior.

  The floor cross members 34, 35, 36 all extend substantially along the vehicle width direction, and both ends in the extending direction are coupled to the left and right side sills 14. The floor cross members 34, 35, and 36 are spaced apart from each other in the longitudinal direction of the vehicle body.

7 and 8 are perspective views partially in section at a portion along line VII-VII in FIG. FIG. 7 is a view of the cross-sectional portion as viewed from diagonally upward on the rear right side, and FIG.
As shown in FIGS. 3, 7, and 8, the battery case 28 includes a case main body 28 </ b> A that opens upward, and a case cover 28 </ b> B that closes the upper opening of the case main body 28 </ b> A. The case body 28A includes a bottom wall 28Aa having a substantially rectangular shape in plan view, and a peripheral wall 28Ab that rises upward from the peripheral region of the bottom wall 28Aa. A portion of the peripheral wall 28Ab that rises upward from the left and right side end portions is hereinafter referred to as a case side wall 50.

Inside the battery case 28 are arranged a plurality of batteries 51 (see FIG. 4) and a plurality of battery cross members 45 extending substantially along the vehicle width direction so as to partition the inside of the battery case 28 in the front-rear direction. . In the present embodiment, three battery cross members 45 are provided. Each battery cross member 45 is arranged at a position directly below the floor cross members 34, 35, 36 on the floor panel 16. The three floor cross members 34, 35, 36 and the battery cross member 45 are arranged substantially in parallel.
Each cross section (cross section substantially perpendicular to the front-rear direction of the vehicle) including each of the floor cross members 34, 35, 36 and the corresponding battery cross member 45 has a substantially similar structure. Therefore, in the following, the cross-sectional structure of the lower structure 12 will be described by taking a cross section including the center floor cross member 35 in the front-rear direction and the battery cross member 45 below it as a representative.

  As shown in FIGS. 3, 7, and 8, a rectangular tube-like case frame 52 that extends substantially along the longitudinal direction of the vehicle body is coupled to the outer surface of the case side wall 50 of the case main body 28 </ b> A. In the case frame 52, the lower end of the inner side wall 52a joined to the case side wall 50 of the case main body 28A is bent inward in the vehicle width direction, and an extension piece 52b is provided at the end of the bent portion. The extension piece 52b is superimposed on the lower surface of the bottom wall 28Aa of the case main body 28A, and is joined to the lower surface of the bottom wall 28Aa.

  An attachment frame 53 that bulges outward from the lower region of the case frame 52 in the vehicle width direction is coupled to the outer side of the case frame 52 in the vehicle width direction. The attachment frame 53 forms a horizontally long rectangular cross section together with the outer side wall of the case frame 52 in a state where it is coupled to the case frame 52. This rectangular cross section extends substantially along the longitudinal direction of the vehicle body. The mounting frame 53 is overlapped on the inner lower surfaces of the left and right side sills 14 and is coupled to the lower surfaces of the side sills 14 by fastening members 54.

  Further, the lower wall of the attachment frame 53 is joined to the lower surface of the case frame 52, and a frame extension piece 53a extending around the lower surface side of the bottom wall 28Aa of the case body 28A is provided at the tip of the lower wall. It has been. The frame extension piece 53a is superimposed on the lower surface of the extension piece 52b of the case frame 52, and is joined to the lower surface of the bottom wall 28Aa of the case main body 28A together with the extension piece 52b. The frame extension piece 53a, the extension piece 52b, and the bottom wall 28Aa are joined, for example, by welding in a three-layered state.

4 is a view showing a cross section taken along the line IV-IV in FIG. 3, and FIG. 5 is a perspective view of the lower structure 12 including a cross section taken along the line VV in FIG. FIG. 6 is a view of a part of the lower structure 12 inside the battery case 28 as viewed from the rear upper right oblique side.
4 and 5, the battery cross member 45 has a front body 37f, an upper wall 37u, a rear wall 37r, and a member main body 37 having a substantially U-shaped cross section, and a front wall. A front projecting seat 38 projecting forward from the lower edge of 37f and a rear projecting seat 39 projecting rearward from the lower edge of the rear wall 37r are provided.

A plurality of locations spaced apart in the vehicle width direction at the top of the battery cross member 45 are coupled to the corresponding floor cross member 35 above by a plurality of stud bolts 46 that are fastening members. Specifically, the upper wall 37 u of the member main body 37 of the battery cross member 45 is coupled to the left half and the right half of the floor cross member 35 by four stud bolts 46.
As shown in FIG. 4, the stud bolt 46 has a substantially cylindrical central barrel portion 46a, a lower screw portion 46b that projects downward from the lower surface of the barrel portion 46a, and an upward projection from the upper surface of the barrel portion 46a. And an upper threaded portion 46c.

  In the battery cross member 45, the lower end of the stud bolt 46 is coupled to the upper wall 37 u of the member main body portion 37. As shown in FIG. 4, the stud bolt 46 is fixed to the battery cross member 45 by a nut 47 being screwed into a screw portion 46 b that penetrates the upper wall 37 u of the member main body portion 37 downward from above. Each stud bolt 46 has a threaded portion 46c that penetrates the floor panel 16 upward from below, further penetrates the bracket 48 of the floor cross member 35 upward, and a nut 49 is screwed to the threaded 46c portion. . The upper portion of the stud bolt 46 is fixed to the floor cross member 35 by this.

  The bracket 48 is a metal member having a substantially hat-shaped cross section that also serves as a cross-sectional reinforcing portion of the floor cross member 35 (cross plate 65 described later). The bracket 48 has a portion corresponding to the hat-shaped flange portion joined to the lower surface of the upper wall of the floor cross member 35 (cross plate 65), and a portion corresponding to the top portion of the hat-shaped portion to the threaded portion 46c of the stud bolt 46. An insertion hole 48a is formed in which is inserted. The stud bolt 46 is welded to the upper wall of the floor cross member 35 so that the top of the hat shape faces downward. A work hole 55 for tightening the nut 49 to the threaded portion 46c protruding upward from the insertion hole 48a is formed in a portion of the upper wall of the floor cross member 35 facing the insertion hole 48a of the bracket 48.

  In addition, as shown in FIG. 4, the trunk portion 46a of the stud bolt 46 is provided with a support flange 46aA and a small-diameter shaft portion 46aB protruding upward from the support flange 46aA. A thick cylindrical elastic seal member 56 is fitted to the shaft portion 46aB. A support groove 56a is provided on the outer peripheral surface of the elastic seal member 56, and the support groove 56a portion is locked to the peripheral edge portion of the through hole 57 of the case cover 28B. The trunk portion 46 a of the stud bolt 46 is held in the through hole 57 of the case cover 28 </ b> B via the elastic seal member 56. Further, the lower surface of the elastic seal member 56 contacts the upper surface of the support flange 46aA, and the upper surface of the elastic seal member 56 contacts the lower surface of the floor panel 16.

  Further, as shown in FIGS. 3, 7, and the like, the inside of the battery cross member 45 includes the first partition member 58 and the first partition member 58 before and after the installation portion of each stud bolt 46 in the extending direction of the battery cross member 45. Two partition members 59 are provided. Each of the first partition member 58 and the second partition member 59 has joining flanges 58a and 59a (see FIG. 6), and the front wall 37f, the upper wall 37u, and the rear wall 37r of the battery cross member 45 are provided. At least three surfaces are fixed by welding or the like.

  As shown in FIG. 5, the member main body portion 37 of the battery cross member 45 has a substantially U-shaped cross section joined to the upper wall 37u, the front wall 37f, and the rear wall 37r of the member main body portion 37. A reinforcing plate 20 is arranged. In other words, each wall of the member main body 37 is made into a double wall by the metal reinforcing plate 20, and the above-described members are coupled to the walls reinforced by the reinforcing plate 20.

  By the way, the battery cross member 45 extends rearward from the lower edge of the front wall 37f of the member main body 37 and the lower edge of the rear wall 37r of the member main body 37, as described above. The rear overhanging seat 39 is provided. That is, the side member 45S and the central member 45C are formed in an inverted T-shaped cross section.

  In the battery cross member 45, a front projecting seat 38 and a rear projecting seat 39 are arranged to face the upper surface of the bottom wall 28 </ b> Aa of the battery case 28. On the other hand, a lower surface reinforcing member 61 is disposed at a position directly below the installation portion of the battery cross member 45 in the lower surface of the bottom wall 28Aa of the battery case 28.

  The lower surface reinforcing member 61 is configured by a metal plate-like member whose substantially wave-shaped cross section extends substantially along the vehicle width direction. The front projecting seat 38 and the rear projecting seat 39 of the battery cross member 45 are coupled to the lower surface reinforcing member 61 with the bottom wall 28Aa of the battery case 28 sandwiched therebetween. For example, the flat flanges of the front overhanging seat 38 and the rear overhanging seat 39 and the flat flange of the lower surface reinforcing member 61 are overlapped on the upper and lower surfaces of the bottom wall 28Aa, and in this state, the members are welded in a three-ply manner. Has been. Thus, the battery cross member 45 is integrated with the lower surface reinforcing member 61 on the lower surface with the front projecting seat 38 and the rear projecting seat 39 projecting forward and backward from the member main body 37 with the bottom wall 28Aa interposed therebetween.

  Further, in the end region of the battery cross member 45 in the vehicle width direction, the extension piece 52b of the case frame 52 described above is joined to the lower surface of the bottom wall 28Aa of the battery case 28 as shown in FIGS. ing. The extension piece 52b constitutes a lower surface reinforcing member, and, like the lower surface reinforcing member 61, the front projecting seat 38 and the rear projecting seat 39 are coupled with the bottom wall 28Aa interposed therebetween.

  As shown in FIGS. 4 and 5, a part of the base portion side (side connected to the member main body portion 37) of the front overhanging seat 38 and the rear overhanging seat 39 of the battery cross member 45 has a peripheral edge. A pedestal portion 23 bulging upward with respect to the joint surface with the bottom wall 28Aa and having a flat upper surface is provided. As shown in FIG. 4, the pedestal 23 can place a battery 51 on the upper surface thereof. Further, the lower surface side of the pedestal portion 23 communicates with the internal space of the member main body portion 37.

  Here, as shown in FIG. 3, the floor cross member 35 is joined to the upper surface of the floor panel 16, and forms a closed cross section extending substantially along the vehicle width direction with the floor panel 16. 65, the bottom surface of the end region of the floor panel 16 in the vehicle width direction, and the inner side surface of the side sill 14, and a closed cross section is formed between the floor panel 16 and extending substantially along the vehicle width direction. And a gusset plate 66. The cross plate 65 has a substantially hat-shaped cross section, and both end portions in the vehicle width direction are joined to the upper surfaces of the left and right side sills 14. The cross section of the gusset plate 66 is formed in a substantially hat shape, and both end portions in the vehicle width direction are joined to the lower surface of the floor panel 16 and the inner side surface of the side sill 14. In the present embodiment, the cross plate 65 is configured by joining a plurality of plate materials.

  The upper wall of the end region of the cross plate 65 in the vehicle width direction is inclined downward toward the outer side in the vehicle width direction. As a result, the closed cross section formed by the cross plate 65 and the upper surface of the floor panel 16 has an inner opening area gradually narrowing toward the outside in the vehicle width direction. Similarly, the lower wall of the gusset plate 66 is inclined downward toward the outer side in the vehicle width direction. As a result, the closed cross section formed by the gusset plate 66 and the lower surface of the floor panel 16 has an internal opening area that gradually expands outward in the vehicle width direction.

  The floor cross member 35 has a shape in which a central region in the vehicle width direction is lifted upward with respect to the side sill 14. However, the floor cross member 35 has a closed cross section in the central region formed by the floor panel 16 and the cross plate 65 and an inclined closed cross section in the end region formed by the cross plate 65 and the gusset plate 66 by the above configuration. Are continuous with a substantially constant cross-sectional area.

As described above, in the vehicle lower structure 12 according to the present embodiment, the front projecting seat 38 and the rear projecting seat 39 are extended from the lower edge of the member main body portion 37 of the battery cross member 45, A rear projecting seat 39 is coupled to the bottom wall 28Aa of the battery case 28. When an impact load is input, for example, when a load in the front-rear direction is input from the seat belt to the vehicle body side cross member, the load is supplied to the member main body portion 37 of the battery cross member 45 via the stud bolt 46 that is a fastening member. Is entered at the top of At this time, a moment in a direction of tilting back and forth through the stud bolt 46 acts on the member main body portion 37, and the moments are a front overhanging seat 38 and a rear overhanging seat 39 projecting back and forth from the lower edge of the member main body portion 37. The battery case 28 is received by each connecting portion. For this reason, when a load in the front-rear direction is input from the floor cross member 35 (vehicle body-side cross member) to the battery cross member 45, the battery cross member 45 can be prevented from tilting in the front-rear direction with high rigidity.
Therefore, by adopting the lower structure 12 of the present embodiment, the support rigidity of the floor cross member 35 can be maintained high.

In the vehicle lower structure 12 according to the present embodiment, the front overhanging seat 38 and the rear overhanging seat 39 are disposed on the upper surface side of the bottom wall 28Aa of the battery case 28, and the lower surface reinforcing member is disposed on the lower surface side of the bottom wall 28Aa. 61 is disposed, and the front projecting seat 38 and the rear projecting seat 39 are coupled to the lower surface reinforcing member 61 with the bottom wall 28Aa interposed therebetween. Thus, the front projecting seat 38 and the rear projecting seat 39 of the battery cross member 45 are integrated with the bottom wall 28Aa of the battery case 28 together with the lower surface reinforcing member 61. Therefore, when this configuration is adopted, it is possible to more firmly suppress the front-rear tilting of the member main body portion 37 of the battery cross member 45.
Moreover, when this structure is employ | adopted, each member couple | bonded with the battery cross member 45 can be comprised by the press-molded goods which can be manufactured at low cost, and members can be fixed by welding.

  In particular, in the present embodiment, the lower surface reinforcing member is constituted by a plate-like member having a substantially wave-shaped cross section extending substantially along the vehicle width direction. The rigidity of the bottom wall 28Aa can be increased efficiently.

  Further, in the vehicle lower structure 12 according to the present embodiment, a case frame 52 is coupled to the outside of the case side wall 50 of the battery case 28, and an extension piece 52 b extending from the case frame 52 is a bottom wall of the battery case 28. The front projecting seat 38 and the rear projecting seat 39 of the battery cross member 45 are joined to the extension piece 52b with the bottom wall 28Aa interposed therebetween. Therefore, in the end region of the battery cross member 45 in the vehicle width direction, the front projecting seat 38 and the rear projecting seat 39 are integrated with the extension piece 52b with the bottom wall 28Aa of the battery case 28 sandwiched therebetween. Become. Therefore, when this configuration is adopted, the front-rear tilting of the member main body 37 of the battery cross member 45 can be more firmly regulated.

  Furthermore, in the vehicle lower structure 12 according to the present embodiment, the upper wall 37u and the front wall of the member main body 37 are located in the vicinity of the fastening portion of the stud bolt 46 in the member main body 37 of the battery cross member 45. The first partition member 58 and the second partition member 59 that constrain the three surfaces 37f and the rear wall 37r are coupled. Thereby, since the cross-sectional rigidity of the member main body near the fastening portion of the stud bolt 46 is enhanced by the first partition wall member 58 and the second partition wall member 59, the cross-sectional deformation near the fastening portion of the stud bolt 46 is efficiently suppressed. can do. Therefore, when this configuration is adopted, even when the thickness of the member main body portion 37 must be reduced in order to reduce the weight, the tilting and sinking of the stud bolt 46 is suppressed, and the floor cross member 35 is suppressed. Can be supported by the battery cross member 45 with high rigidity.

  Further, the vehicle lower structure 12 according to the present embodiment includes a floor cross member 35 (vehicle body side cross member), a cross plate 65 having a substantially hat-shaped cross section in which both end portions in the vehicle width direction are installed on the side sill 14; A gusset plate 66 having a substantially hat-shaped cross section that is laid on the lower surface of the end region in the vehicle width direction of the floor panel 16 and the side surface of the side sill 14, and the end region in the vehicle width direction of the cross plate 65 and the gusset plate 66 is formed so as to incline downward toward the outer side in the vehicle width direction. A bracket 48 that also serves as a cross-sectional reinforcing portion is attached to the inside of the cross plate 65 near the center in the vehicle width direction, and the bracket 48 is coupled to the member main body 37 of the battery cross member 45 by a stud bolt 46. Therefore, the left and right side sills 14 can be connected by the substantially constant continuous closed cross section of the floor cross member 35 while the central region of the floor cross member 35 is lifted upward with respect to the side sill 14.

When the above configuration is adopted, since the central region of the floor cross member 35 is lifted upward with respect to the side sill 14, the battery case 28 disposed below the central region of the floor cross member 35 is placed on the upper side. Can be located. Therefore, the ground clearance below the battery case 28 can be easily ensured.
In the case of the above configuration, the cross section of the central region of the cross plate 65 is reinforced by the bracket 48 that also serves as a cross-section reinforcing portion, and the bracket 48 is coupled to the battery cross member 45 by the stud bolt 46. For this reason, when a load is input to the floor cross member 35, the input load can be supported by the battery cross member 45 in a state where the cross-sectional deformation of the cross plate 65 is suppressed.

Furthermore, in the case of the present embodiment, the body 46a of the stud bolt 46 that connects the battery cross member 45 and the floor cross member 35 is held in the through hole 57 of the case cover 28B via the elastic seal member 56. For this reason, when the stud bolt 46 and the floor cross member 35 are fastened and fixed, the position and direction of the screw portion 46c protruding above the case cover 28B can be finely adjusted. Therefore, when this configuration is adopted, the workability of fastening the floor cross member 35 to the stud bolt 46 is improved.
In addition, when this configuration is adopted, since the through hole 57 of the case cover 28B is closed by the elastic seal member 56, it is possible to prevent water from entering the battery case 28 through the through hole 57. In the case of this embodiment, since the elastic seal member 56 is interposed between the stud bolt 46 and the case cover 28B, the vibration of the case cover 28B can be suppressed by the elastic seal member 56.

  Further, in the above configuration, when the upper surface of the elastic seal member 56 is brought into contact with the lower surface of the peripheral area of the through hole 57 of the floor panel 16, water enters the vehicle interior through the through hole 57 of the floor panel 16. This can be prevented by the elastic seal member 56. Further, in this case, the vibration of the floor panel 16 can be suppressed by the elastic seal member 56.

  Further, in the vehicle lower structure 12 according to the present embodiment, a frame extension piece 53 a extending from the attachment frame 53 is coupled to the case frame 52 and an attachment frame 53 that couples the case frame 52 to the lower surface of the side sill 14. Is superimposed on the lower surface of the extension piece 52b of the case frame 52, and the frame extension piece 53a is coupled to the bottom wall 28Aa of the battery case 28 together with the extension piece 52b. For this reason, the coupling of the attachment frame 53 and the case frame 52 can be further strengthened, and the rigidity of the bottom wall 28Aa of the battery case 28 can be increased.

  In the vehicle lower structure 12 according to the present embodiment, the member main body 37 is joined to the upper wall 37u, the front wall 37f, and the rear wall 37r inside the member main body 37 of the battery cross member 45. A reinforcing plate 20 having a substantially U-shaped cross section is disposed. For this reason, the rigidity of the member main body 37 to which the stud bolt 46 is fastened can be easily increased with a simple configuration. Further, since the reinforcing plate 20 can be formed by a press-molded product that can be manufactured at a low cost, the product cost can be reduced.

  Further, in the case of the vehicle lower structure 12 according to the present embodiment, the front projecting seat 38 and the rear projecting seat 39 protrude upward, the lower surface communicates with the internal space of the member main body 37, and the upper surface is substantially flat. A pedestal portion 23 is provided. For this reason, the upper surface of the base part 23 provided in the front overhanging seat 38 and the back overhanging seat 39 can be utilized as a battery support portion or the like. In addition, when this configuration is adopted, the lower surface side of the front overhanging seat 38 and the rear overhanging seat 39 can be communicated with the internal space of the member main body portion 37 with a wide opening area by the pedestal portion 23 standing upward. Sometimes, the electrodeposition coating liquid for rust prevention can be easily spread to every corner of the battery cross member 45.

  In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary.

DESCRIPTION OF SYMBOLS 12 ... Lower structure 14 ... Side sill 16 ... Floor panel 28 ... Battery case 20 ... Reinforcement plate 23 ... Base part 28A ... Case main body 28Aa ... Bottom wall 28B ... Case cover 35 ... Floor cross member (vehicle body side cross member)
37 ... Member main body portion 37f ... Front wall 37u ... Upper wall 37r ... Rear wall 38 ... Front projecting seat 39 ... Rear projecting seat 45 ... Battery cross member 46 ... Stud bolt (fastening member)
46a ... trunk 46c ... thread 48 ... bracket 48a ... insertion hole 50 ... case side wall 52 ... case frame 52
52b ... Extension piece 53 ... Mounting frame 53a ... Frame extension piece 56 ... Elastic seal member 57 ... Through hole 58 ... First partition member (partition member)
59 ... Second partition member (partition member)
61 ... lower surface reinforcing member 65 ... cross plate 66 ... gusset plate

Claims (10)

A pair of side sills arranged on the left and right sides of the vehicle body and extending substantially along the longitudinal direction of the vehicle body;
A battery case in which a battery is housed and left and right edges are installed on the pair of side sills;
A battery cross member provided in the battery case and extending substantially along the vehicle width direction;
A vehicle body-side cross member extending substantially along the vehicle width direction on the upper side of the battery cross member, having both end portions laid on the pair of side sills, and an intermediate region coupled to the battery cross member by a fastening member; With
The battery cross member is a member main body portion that stands upward and has an upper portion coupled to the vehicle body side cross member by the fastening member, a front projecting seat that projects forward from a lower edge of the member main body portion, An inverted T-shaped cross section having a rear projecting seat projecting rearward from the lower edge of the member main body, and the front projecting seat and the rear projecting seat are coupled to the bottom wall of the battery case. A vehicle lower structure characterized by the above. The front projecting seat and the rear projecting seat are disposed on the upper surface side of the bottom wall of the battery case,
A lower surface reinforcing member is disposed on the lower surface side of the bottom wall,
The vehicle lower structure according to claim 1, wherein the front overhanging seat and the rear overhanging seat are coupled to the lower surface reinforcing member with the bottom wall interposed therebetween.   The vehicle lower structure according to claim 2, wherein the lower surface reinforcing member is constituted by a plate-like member having a substantially wave-shaped cross section extending substantially along the vehicle width direction. The battery case has a case side wall that rises upward from left and right ends of the bottom wall,
A case frame extending substantially along the longitudinal direction of the vehicle body is coupled to the outside of the case side wall,
The case frame has an extension piece arranged on the lower surface of the bottom wall of the battery case and constituting the lower surface reinforcing member,
The vehicle lower structure according to claim 2, wherein the front overhanging seat and the rear overhanging seat are coupled to the extension piece with the bottom wall sandwiched therebetween. The member main body portion of the battery cross member has an upper wall, a front wall extending downward from a front portion of the upper wall, and a rear wall extending downward from a rear portion of the upper wall,
A partition wall member that binds three surfaces of the upper wall, the front wall, and the rear wall of the member main body is coupled to the member main body in the vicinity of the fixing portion of the fastening member. Item 5. The vehicle lower structure according to any one of Items 1 to 4. A floor panel is disposed above the battery case,
The vehicle body side cross member is:
A cross section joined to the upper surface of the floor panel to form a closed cross section extending substantially along the vehicle width direction with the floor panel, and both ends of the vehicle width direction are installed on the pair of side sills. A substantially hat-shaped cross plate;
A cross-sectional substantially hat-shaped cross-section that is installed on the lower surface of the end region in the vehicle width direction of the floor panel and the side surface of the side sill and forms a closed cross section extending substantially along the vehicle width direction between the floor panel. A gusset plate, and
An end region in the vehicle width direction of the cross plate and the gusset plate are formed so as to be inclined downward toward the outer side in the vehicle width direction,
In the vehicle width direction center region of the cross plate, a bracket that also serves as a cross-section reinforcing portion is attached to the inside, and the bracket is coupled to the member main body portion of the battery cross member by the fastening member. The vehicle lower structure according to any one of claims 1 to 5. The battery case includes a case main body in which the battery and the battery cross member are disposed and an upper side is opened, and a case cover that closes the opening of the case main body,
The fastening member is a stud bolt whose both ends are fastened to the bracket and the battery cross member,
The vehicle lower structure according to claim 6, wherein a body portion of the stud bolt is held in a through hole of the case cover via an elastic seal member. The case frame is coupled with a mounting frame that connects the case frame to the lower surface of the side sill,
In the mounting frame, a frame extension piece that overlaps the lower surface of the extension piece of the case frame is extended,
The vehicle lower structure according to claim 4, wherein the frame extension piece is coupled to the bottom wall of the battery case together with the extension piece. The member main body portion of the battery cross member has an upper wall, a front wall extending downward from a front portion of the upper wall, and a rear wall extending downward from a rear portion of the upper wall,
9. A reinforcing plate having a substantially U-shaped cross section that is joined to the upper wall, the front wall, and the rear wall is disposed inside the member main body. The vehicle lower structure according to claim 1.   10. The front overhanging seat and the rear overhanging seat are provided with a pedestal portion that protrudes upward and whose lower surface communicates with the internal space of the member main body, and whose upper surface is substantially flat. The vehicle lower structure according to any one of the above.

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