JP2018188086A - Vehicle body lower structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle body lower structure that is able to protect a battery in a battery pack while satisfactorily ensuring convenience for boarding the vehicle and alighting from it.SOLUTION: A vehicle body lower structure 12 comprises a left side sill 14, an outer bulk head 52, and an inner bulk head 56. The outer bulk head 52 is disposed between the outer side-sill 65 and a stiffener 67 and mounted on the stiffener 67. An inner bulk head 56 is disposed between an inner side-sill 66 and the stiffener 67 and mounted on the stiffener 67. The outer bulk head 52 is formed in the shape of a box of rectangular cross-section, a side wall 84 of which extends in a vehicle width direction. The inner bulk head 56 is formed in the shape of a box of rectangular cross-section, a side wall 91 of which extends in the vehicle width direction.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a vehicle body lower structure.

  As a lower body structure, for example, a structure in which a floor panel is installed between a left side sill and a right side sill and a battery pack is mounted below the floor panel is known. A battery is accommodated in the battery pack. The battery in the battery pack needs to be protected from a load input from the side of the vehicle. For this reason, the height of the side sill is increased and an energy absorbing member is provided inside the side sill. By absorbing the impact load input from the side of the vehicle with the energy absorbing member, it becomes possible to protect the battery (that is, the on-vehicle component) in the battery pack (see, for example, Patent Document 1).

  Among the vehicle body lower structures, for example, a structure in which a side sill is divided into a vehicle body side rocker and a battery pack side rocker is known. The vehicle body side locker is positioned above, and the battery pack side locker is positioned below. By dividing the side sill into each rocker, when the impact load is input from the side of the vehicle, the input impact load is dispersed to the vehicle body side rocker and the battery pack side rocker. By crushing each rocker with the dispersed load and absorbing the impact energy, it becomes possible to protect the battery (that is, the on-vehicle component) in the battery pack (see, for example, Patent Document 2).

U.S. Pat. No. 8,702,161 U.S. Pat. No. 9,505,442

However, in the lower body structure of Patent Document 1, the height of the side sill is increased. Therefore, the upper part of the side sill is located above the floor panel. For this reason, when the passenger gets on and off, the side sill becomes an obstacle, and it is difficult to ensure a good passenger's getting on and off.
Moreover, the vehicle body lower part structure of Patent Document 2 is divided into a vehicle body side rocker having an upper side sill and a battery pack side rocker having a lower side sill. Therefore, like the lower body structure of Patent Document 1, the upper part of the side sill is located above the floor panel. For this reason, when the passenger gets on and off, the side sill becomes an obstacle, and it is difficult to ensure a good passenger's getting on and off.

  In view of this, the present invention provides a vehicle body lower structure capable of protecting in-vehicle components from an impact load input from the side of the vehicle in a state in which passenger occupancy is satisfactorily secured.

  In order to solve the above-described problem, the vehicle body lower part structure of the invention described in claim 1 includes a stiffener between a side sill outer (for example, the side sill outer 65 of the embodiment) and a side sill inner (for example, the side sill inner 66 of the embodiment). The side sill (for example, the left and right side sills 14 and 15 of the embodiment) sandwiched between the side sill outer and the stiffener (for example, the stiffener 67 of the embodiment), and the outer bulkhead attached to the stiffener ( For example, the first to third outer bulkheads 51 to 53 of the embodiment and the inner bulkhead (for example, the first to first of the embodiments) disposed between the side sill inner and the stiffener and attached to the stiffener. 3 inner bulkheads 55-57), the outer bulkhead and the inner bulk The lid is formed in a box shape having a polygonal cross section in which openings (for example, the openings 87 and 94 in the embodiment) are opened on the stiffener side, and extends in a direction away from the stiffener (for example, in the embodiment). Side walls 84, 91), a bottom portion of the side walls on one side away from the stiffener (for example, bottom portions 85, 92 of the embodiment), and the other side portion of the side walls on the opening side. And a joining flange that is joined to each other via the stiffener (for example, the joining flanges 86 and 93 of the embodiment).

In this way, the joining flanges of the outer bulkhead and the inner bulkhead are joined together via the stiffener. The box shape of the outer bulkhead and the inner bulkhead is constrained by the joint flange. Therefore, when an impact load is input from the side of the vehicle, the load is transmitted to the entire area of the side wall of each bulkhead (that is, the entire circumference). Thereby, the side wall of the perimeter of an outer bulkhead or an inner bulkhead can be buckled with a load, and impact energy can be absorbed.
Here, when the battery pack is mounted inside the side sill in the vehicle width direction, the impact load input from the side of the vehicle can be absorbed by the outer bulkhead or the inner bulkhead. Thereby, the battery (namely, vehicle-mounted component) accommodated in the inside of a battery pack can be protected from an impact load.

In addition, the outer bulkhead was arranged outside the stiffener in the vehicle width direction, and the inner bulkhead was arranged inside the stiffener in the vehicle width direction. The outer bulkhead and the inner bulkhead can be arranged side by side in the vehicle width direction. Therefore, the outer bulkhead and the inner bulkhead can be provided inside the side sill without increasing the height of the side sill.
As a result, the height of the side sill can be suppressed, and the side sill does not get in the way when the occupant gets in and out, so that the occupant can easily get in and out.

  According to a second aspect of the present invention, the side sill is provided on both sides of a vehicle body (for example, the vehicle body 10 of the embodiment), and the floor cross member (for example, the embodiment) is laid between the side sills in the vehicle width direction. 1 to 3 floor cross members 34 to 36), and the outer bulk head and the inner bulk head are provided so as to overlap the floor cross member in the vehicle width direction. .

  Thus, the outer bulkhead and the inner bulkhead were provided so as to overlap the floor cross member. Therefore, when an impact load is input from the side of the vehicle, the load passing through the outer bulkhead and the inner bulkhead can be favorably supported by the floor cross member. Thereby, the outer bulkhead and the inner bulkhead can be sufficiently crushed by the impact load input from the side of the vehicle to absorb the impact energy.

  According to a third aspect of the present invention, at least a pair of the floor cross members are provided at intervals in the longitudinal direction of the vehicle body, and seats (for example, the driver seat 31 and the passenger seat 32 of the embodiment) are provided on the pair of floor cross members. Is attached.

  In this way, the seat is attached to the pair of floor cross members. The pair of floor cross members are installed on side sills on both sides of the vehicle body. Therefore, the impact load input from the side of the vehicle can be sufficiently absorbed by the outer bulkhead and the inner bulkhead, and the remaining load can be supported by the pair of floor cross members. Thereby, it can suppress that vehicle body side parts, such as a side sill, deform | transform to a sheet | seat, and can protect a passenger | crew from an impact load.

  According to a fourth aspect of the present invention, the floor panel is attached to the upper portion of the side sill (for example, the side sill upper portion 82 of the embodiment), and the floor cross member is provided on the upper surface (for example, the upper surface 16a of the floor panel of the embodiment). For example, the floor panel 16 of the embodiment, the inner wall of the side sill (for example, the side sill inner wall 81 of the embodiment), and the lower surface of the floor panel (for example, the lower surface 16b of the floor panel of the embodiment) are spanned from the lower surface. A gusset (for example, the first to third gussets 61 to 63 of the embodiment) extending downward in the vehicle width direction to the inner wall, and the gusset is attached to the inner bulkhead of the inner wall. At the opposite part (for example, the part 81a of the side sill inner wall 81 of the embodiment facing the inner bulkhead 55). The floor cross member has a member upper portion (for example, the member upper portion 101 in the embodiment) located above the upper portion of the side sill, and the member upper portion is directed outward in the vehicle width direction to the upper portion of the side sill. And an upper inclined portion extending downwardly.

  Thus, a floor panel can be arrange | positioned at the same height as a side sill by attaching a floor panel to the upper part of a side sill. Thus, the side sill does not get in the way when the passenger gets on and off, and the passenger can get on and off satisfactorily.

Moreover, the upper part of the floor cross member has an upper inclined part, and the upper inclined part extends to the upper part of the side sill toward the outer side in the vehicle width direction so as to descend downward. Furthermore, the gusset was extended downward from the lower surface of the floor panel to the inner wall of the side sill in the vehicle width direction. Therefore, it is possible to form a section substantially the same as the section of the floor cross member with the upper inclined portion and the gusset. Further, the cross section formed by the upper inclined portion and the gusset can be a cross section having substantially the same size as the floor cross member.
Thereby, when an impact load is input from the side of the vehicle, the load can be transmitted from the inner bulkhead to the gusset through the inner wall of the side sill. The load transmitted to the gusset can be transmitted to the floor cross member, and the floor cross member can support the load.

  Furthermore, by providing a floor cross member on the upper surface of the floor panel, the floor cross member can be removed from below the floor panel. Thereby, the capacity | capacitance of underfloor mounting components, such as a battery pack provided below a floor panel, can be increased.

  The invention described in claim 5 is a battery pack (for example, the battery pack 28 of the embodiment) that is provided at a predetermined interval inside the side sill of the side sill and accommodates a battery (for example, the battery 123 of the embodiment). A battery cross member (for example, the battery cross member 131 of the embodiment) provided in the battery pack (for example, the interior 129 of the battery pack 28 of the embodiment) and extending in the vehicle width direction, and a side wall of the battery pack (For example, the battery pack frame (for example, the battery pack frame 29 of the embodiment) attached to the case wall portion 124 and the left side wall 124a of the embodiment), and the battery pack frame is a lower portion (for example, of the side sill) The fixing part (for example, the side sill lower part 83) of the embodiment (for example, The fixing portion 143) of the embodiment, the battery cloth raised from the fixing portion toward the inner wall of the side sill, facing the inner bulkhead via the inner wall, and via the side wall of the battery pack And a frame main body (for example, the frame main body 144 according to the embodiment) attached to the member.

  Thus, the fixing part was attached to the lower part of the side sill. Further, the frame body of the battery pack frame was raised toward the inner wall of the side sill, and opposed to the inner bulkhead via the inner wall. Further, the frame body was attached to the battery cross member. Therefore, when an impact load is input from the side of the vehicle, the load can be transmitted to the fixed portion through the lower portion of the side sill, and transmitted from the fixed portion to the battery cross member. Further, the impact load input from the side of the vehicle can be transmitted from the inner bulkhead to the frame body through the inner wall of the side sill, and from the frame body to the battery cross member.

  That is, the impact load input from the side of the vehicle can be supported by the battery cross member. Thereby, the inner bulkhead can be sufficiently crushed by the impact load to absorb the impact energy well. In addition, the fixed portion and the frame main body can be crushed by an impact load input from the side of the vehicle. As a result, the battery accommodated in the battery pack can be protected from an impact load.

  According to a sixth aspect of the present invention, the stiffener has a hole portion (for example, the hole portion 96 in the embodiment) formed in a portion corresponding to the opening portion of the outer bulkhead and the inner bulkhead. Features.

Thus, by forming the hole in the stiffener, the electrodeposition paint can be well guided to the inside of the side sill using the hole when the inside of the side sill is electrodeposited. Thereby, an electrodeposition paint can be easily attached to the inside of the side sill.
Moreover, by forming a hole in the stiffener, the weight of the stiffener (that is, the vehicle body) can be reduced.

According to this invention, the outer bulkhead is disposed on the outer side in the vehicle width direction of the stiffener, and the inner bulkhead is disposed on the inner side in the vehicle width direction of the stiffener. By arranging the outer bulkhead and the inner bulkhead side by side in the vehicle width direction, the outer bulkhead and the inner bulkhead can be provided inside the side sill without increasing the height of the side sill.
Thereby, in-vehicle components can be protected from the impact load input from the side of the vehicle in a state in which the occupant's boarding / exiting performance is well secured.

It is a perspective view which shows the vehicle body lower part structure in one Embodiment of this invention. It is a top view which shows the vehicle body lower part structure in one Embodiment of this invention. It is a perspective view which shows the state which removed the sheet | seat from the vehicle body lower structure in one Embodiment of this invention. It is sectional drawing which shows the state which fractured | ruptured the vehicle body lower structure in one Embodiment of this invention along the IV-IV line of FIG. FIG. 5 is a cross-sectional view showing an enlargement of a portion V in FIG. It is a perspective view which shows the outer bulkhead and inner bulkhead of the vehicle body lower structure in one Embodiment of this invention. It is a disassembled perspective view which shows the outer bulkhead and inner bulkhead of the vehicle body lower structure in one Embodiment of this invention. It is a perspective view which shows the gusset of the vehicle body lower structure in one Embodiment of this invention. It is a perspective view shown in the state where a battery pack frame of a lower body structure in one embodiment of the present invention was fractured. It is sectional drawing explaining the example which protects a battery from the impact load input from the vehicle side by the vehicle body lower part structure in one Embodiment of this invention.

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.
As shown in FIGS. 1 and 2, the vehicle body 10 includes a vehicle body lower structure 12 that constitutes a lower portion of the vehicle body 10. The vehicle body lower structure 12 includes a left side sill 14, a right side sill 15, a floor panel 16, a floor cross member unit 17, a left outer bulkhead unit 18, a left inner bulkhead unit 19, and a right outer bulk. A head unit 21, a right inner bulkhead unit 22, a left gusset unit 24, and a right gusset unit 25 are provided.

The vehicle body lower structure 12 includes a battery pack 28 (see FIG. 4), a battery pack frame 29 (see FIG. 4), a driver seat 31, and a passenger seat 32.
In addition, since the vehicle body lower structure 12 is comprised by the substantially left-right symmetric member, hereafter, the left side structural member is demonstrated and description of the right side structural member is abbreviate | omitted.

The left side sill 14 is provided on the left side portion 10 a of both side portions of the vehicle body 10 and extends in the vehicle body front-rear direction. The right side sill 15 is provided on the right side portion 10b of both side portions of the vehicle body 10 and extends in the vehicle body front-rear direction.
A floor panel 16 is installed on the left side sill 14 and the right side sill 15. A floor cross member unit 17 is attached to the upper surface 16 a of the floor panel 16. The floor cross member unit 17 includes a first floor cross member 34, a second floor cross member 35, and a third floor cross member 36.

The first floor cross member 34 is disposed on the vehicle body front side in the passenger compartment 38. The first floor cross member 34 is installed on the left side sill 14 and the right side sill 15 so as to face the vehicle width direction.
The second floor cross member 35 is disposed on the vehicle body rear side of the first floor cross member 34. The second floor cross member 35 is installed on the left side sill 14 and the right side sill 15 in the vehicle width direction, and extends in parallel with the first floor cross member 34.
The third floor cross member 36 is disposed on the vehicle body rear side of the second floor cross member 35. The third floor cross member 36 is installed on the left side sill 14 and the right side sill 15 so as to face in the vehicle width direction, and extends in parallel with the second floor cross member 35.

  The first floor cross member 34, the second floor cross member 35, and the third floor cross member 36 are provided at intervals in the longitudinal direction of the vehicle body. For example, a driver seat 31 is attached to the right half of the first floor cross member 34 and the second floor cross member 35 with fastening members such as bolts 37 and nuts. For example, a passenger seat 32 is attached to the left half of the first floor cross member 34 and the second floor cross member 35 with fastening members such as bolts 41 and nuts 42 (see FIG. 4). A rear seat 43 is provided on the third floor cross member 36.

As described above, the driver seat 31 is attached to the right half of the first floor cross member 34 and the second floor cross member 35. A passenger seat 32 is attached to the left half of the first floor cross member 34 and the second floor cross member 35. The first floor cross member 34 and the second floor cross member 35 are respectively constructed on the left side sill 14 and the right side sill 15.
The first floor cross member 34, the second floor cross member 35, and the third floor cross member 36 are similar members. Hereinafter, the second floor cross member 35 will be described in detail, and the first floor cross member 34 and the first floor cross member 34 will be described. Detailed description of the three-floor cross member 36 is omitted. Hereinafter, the second floor cross member 35 is abbreviated as “floor cross member 35”.

The left outer bulkhead unit 18 includes a first outer bulkhead 51, a second outer bulkhead 52, and a third outer bulkhead 53.
The first outer bulkhead 51 is disposed on an extension line of the first floor cross member 34. The second outer bulkhead 52 is disposed on an extension line of the second floor cross member 35. The third outer bulkhead 53 is disposed on an extension line of the third floor cross member 36.
The first outer bulkhead 51, the second outer bulkhead 52, and the third outer bulkhead 53 are similar members. Hereinafter, the second outer bulkhead 52 will be described in detail as the “outer bulkhead 52”. Detailed description of the third outer bulkheads 51 and 53 will be omitted.

As shown in FIG. 3, the left inner bulkhead unit 19 includes a first inner bulkhead 55, a second inner bulkhead 56, and a third inner bulkhead 57.
The first inner bulkhead 55 is disposed on an extension line of the first floor cross member 34. The second inner bulkhead 56 is disposed on an extension line of the second floor cross member 35. The third inner bulkhead 57 is disposed on an extension line of the third floor cross member 36.
The first inner bulkhead 55, the second inner bulkhead 56, and the third inner bulkhead 57 are similar members. Hereinafter, the second inner bulkhead 56 will be described in detail as an “inner bulkhead 56”. Detailed description of the third inner bulkheads 55 and 57 will be omitted.

Returning to FIG. 2, the left gusset unit 24 includes a first gusset 61, a second gusset 62, and a third gusset 63.
The first gusset 61 is disposed below the inclined portion 99 on the left end side of the first floor cross member 34. The second gusset 62 is disposed below the inclined portion 107 (see also FIG. 4) on the left end side of the second floor cross member 35. The third gusset 63 is disposed below the inclined portion 109 on the left end side of the third floor cross member 36.
The first gusset 61, the second gusset 62, and the third gusset 63 are similar members. Hereinafter, the second gusset 62 will be described in detail as the “gusset 62”, and the first gusset 61 and the third gusset 63 will be described in detail. Is omitted.

As shown in FIGS. 4 and 5, the left side sill 14 includes a side sill outer 65, a side sill inner 66, and a stiffener 67.
The side sill outer 65 is provided on the outer side in the vehicle width direction. The side sill outer 65 has an outer bulging portion 71, an upper flange 72, and a lower flange 73. The outer bulging portion 71 bulges outward from the upper flange 72 and the lower flange 73 in the vehicle width direction. A reinforcing member 74 is attached to the inner surface of the outer bulging portion 71. The upper flange 72 projects upward from the upper end of the outer bulging portion 71. The lower flange 73 projects downward from the lower end of the outer bulging portion 71.

  The side sill inner 66 is provided inside the side sill outer 65 in the vehicle width direction. The side sill inner 66 has an inner bulging portion 76, an upper flange 77, and a lower flange 78. The inner bulging portion 76 bulges inward in the vehicle width direction from the upper flange 77 and the lower flange 78. The inner bulging portion 76 is formed in a U-shaped cross section by an inner wall 81, an upper portion 82, and a lower portion 83. A reinforcing member 79 is attached to the inner surface of the inner bulging portion 76. The upper flange 77 projects upward from the outer end of the upper portion 82. The lower flange 78 projects downward from the outer end of the lower portion 83.

  The stiffener 67 is interposed between the side sill outer 65 and the side sill inner 66. The stiffener 67 is formed in a flat plate shape and is interposed between the side sill outer 65 and the side sill inner 66. Specifically, the upper side portion 67a of the stiffener 67 is joined between the upper flange 72 of the side sill outer 65 and the upper flange 77 of the side sill inner 66. Further, the lower side portion 67 b of the stiffener 67 is joined between the lower flange 73 of the side sill outer 65 and the lower flange 78 of the side sill inner 66. That is, the stiffener 67 is sandwiched between the side sill outer 65 and the side sill inner 66.

The left side sill 14 is formed in an outer shape of a rectangular frame by a side sill outer 65 and a side sill inner 66. The stiffener 67 is disposed in the vertical direction by interposing the upper side 67a of the stiffener 67 between the upper flanges 72 and 77 and interposing the lower side 67b of the stiffener 67 between the lower flanges 73 and 78.
An outer space 88 is formed between the side sill outer 65 and the stiffener 67. Further, an inner space 89 is formed between the side sill inner 66 and the stiffener 67.

As shown in FIGS. 6 and 7, the outer bulkhead 52 is disposed in the outer space 88 between the side sill outer 65 and the stiffener 67. The outer bulkhead 52 has a side wall 84, a bottom 85, and a joining flange 86. The side wall 84 has a front side wall 84a, a rear side wall 84b, an upper side wall 84c, and a lower side wall 84d. The side wall 84 is formed in a rectangular frame shape by the front side wall 84a, the rear side wall 84b, the upper side wall 84c, and the lower side wall 84d.
One end portion of the side wall 84 (the end portion on the side away from the stiffener 67) is closed by the bottom portion 85. The bottom 85 is formed in a rectangular shape. An opening 87 (see also FIG. 5) is formed in a rectangular shape at the other end of the side wall 84 (the end on the stiffener 67 side). A joining flange 86 is formed at the other end of the side wall 84.

The joint flange 86 includes a front joint flange 86a, a rear joint flange 86b, an upper joint flange 86c, and a lower joint flange 86d.
The front joint flange 86a projects from the other end portion of the front side wall 84a toward the front of the vehicle body along the outer surface 67c of the stiffener 67. The rear joint flange 86b projects from the other end of the rear side wall 84b toward the rear of the vehicle body along the outer surface 67c of the stiffener 67. The upper joint flange 86c projects upward along the outer surface 67c of the stiffener 67 from the other end of the upper side wall 84c. The lower joint flange 86d protrudes downward along the outer surface 67c of the stiffener 67 from the other end of the lower side wall 84d.

That is, the joining flange 86 is provided on the entire periphery of the opening 87 at the other end of the side wall 84 on the opening 87 side. A front joint flange 86 a, a rear joint flange 86 b, an upper joint flange 86 c, and a lower joint flange 86 d constituting the joint flange 86 are disposed in contact with the outer surface 67 c of the stiffener 67.
As described above, the outer bulkhead 52 is formed in a box shape (hereinafter referred to as a box shape) having a polygonal cross section (specifically, a rectangular cross section) in which the opening 87 is opened on the stiffener 67 side.

An inner bulkhead 56 is disposed in an inner space 89 between the side sill inner 66 and the stiffener 67. Similar to the outer bulkhead 52, the inner bulkhead 56 has a side wall 91, a bottom 92, and a joining flange 93. The side wall 91 has a front side wall 91a, a rear side wall 91b, an upper side wall 91c, and a lower side wall 91d. The side wall 91 is formed in a rectangular frame shape by the front side wall 91a, the rear side wall 91b, the upper side wall 91c, and the lower side wall 91d.
One end portion of the side wall 91 (the end portion on the side away from the stiffener 67) is closed by the bottom portion 92. The bottom portion 92 is formed in a rectangular shape. An opening 94 is opened at the other end of the side wall 91 (the end on the stiffener 67 side). The opening 94 of the inner bulkhead 56 is opened in the same rectangular shape as the opening 87 of the outer bulkhead 52.
A joining flange 93 is formed at the other end of the side wall 91.

  The joint flange 93 includes a front joint flange 93a, a rear joint flange 93b, an upper joint flange 93c, and a lower joint flange 93d. The front joining flange 93a is projected from the other end portion of the front side wall 91a along the inner surface 67d of the stiffener 67 toward the front of the vehicle body. The rear joint flange 93b extends from the other end of the rear side wall 91b toward the rear of the vehicle body along the inner surface 67d of the stiffener 67. The upper joint flange 93c extends upward along the inner surface 67d of the stiffener 67 from the other end of the upper side wall 91c. The lower joint flange 93d extends downward along the inner surface 67d of the stiffener 67 from the other end of the lower side wall 91d.

That is, the joining flange 93 is provided on the entire periphery of the opening 94 at the other end of the side wall 91 on the opening 94 side. The front joint flange 93 a, the rear joint flange 93 b, the upper joint flange 93 c, and the lower joint flange 93 d that constitute the joint flange 93 are arranged in contact with the inner surface 67 d of the stiffener 67.
The inner bulkhead 56 has a rectangular shape having the same shape as the opening 87 of the outer bulkhead 52, and an opening 94 is opened on the stiffener 67 side, and is formed in a box shape with a polygonal cross section (rectangular cross section in the embodiment). .

In a state where the joining flange 86 of the outer bulkhead 52 is in contact with the outer surface 67 c of the stiffener 67 and the joining flange 93 of the inner bulkhead 56 is in contact with the inner surface 67 d of the stiffener 67, the joining flange 86 and the joining flange 93 are connected to the stiffener 67. Are overlapped. The overlapping joining flange 86 and joining flange 93 are joined to each other via a stiffener 67.
Thereby, the outer bulkhead 52 and the inner bulkhead 56 are attached to the stiffener 67 in a state of being overlapped in the vehicle width direction. Furthermore, the outer bulkhead 52 and the inner bulkhead 56 are provided so as to overlap the floor cross member 35 in the vehicle width direction.

  In this state, the outer bulkhead 52 extends in a direction in which the side wall 84 is separated from the stiffener 67 toward the outside in the vehicle width direction. In addition, the outer bulkhead 52 is closed by a bottom 85 at one end of the side wall 84 on the side away from the stiffener 67. The inner bulkhead 56 extends in a direction in which the side wall 91 is separated from the stiffener 67 inward in the vehicle width direction. In addition, the inner bulkhead 56 is closed by a bottom 92 at one end of the side wall 91 on the side away from the stiffener 67.

As shown in FIGS. 2 and 5, the outer bulkhead 52 and the inner bulkhead 56 are provided so as to overlap the floor cross member 35 in the vehicle width direction. Therefore, when the impact load F1 is input from the side of the vehicle Ve, the outer bulkhead 52 and the inner bulkhead 56 can be crushed by the impact load F1. Further, the load F <b> 2 that has passed through the outer bulkhead 52 and the inner bulkhead 56 can be favorably supported by the floor cross member 35.
Thus, the impact energy can be absorbed by crushing the outer bulkhead 52 and the inner bulkhead 56 with the impact load F1 input from the side of the vehicle Ve.

The remaining load F2 absorbed by the outer bulkhead 52 and the inner bulkhead 56 can be supported by the floor cross member (ie, the second floor cross member) 35. Similarly, the remaining load F <b> 2 absorbed by the outer bulkhead 51 and the inner bulkhead 55 can be supported by the first floor cross member 34.
Thereby, it can suppress that vehicle body side parts, such as the left side sill 14, deform | transform to the passenger seat 32, for example. Further, it is possible to prevent the vehicle body side portion such as the right side sill 15 from being deformed to the driver seat 31.
That is, the passenger of the passenger seat 32 and the driver seat 31 can be protected from the impact load F1.

Returning to FIG. 7, the stiffener 67 has a hole 96. The hole 96 is formed in a portion corresponding to the opening 87 of the outer bulkhead 52 and the opening 94 of the inner bulkhead 56. By forming the hole 96 in the stiffener 67, when the inside of the left side sill 14 is electrodeposited, the electrodeposition paint can be guided well into the left side sill 14 using the hole 96. Thereby, an electrodeposition paint can be easily attached to the inside of the left side sill 14.
Further, by forming the hole 96 in the stiffener 67, the stiffener 67 can be reduced in weight, and the vehicle body 10 can be reduced in weight.

As shown in FIGS. 4 and 6, the left side portion 16 c of the floor panel 16 is attached to the upper portion (upper surface) 82 of the inner bulging portion 76 of the side sill inner 66. The upper part 82 of the inner bulging part 76 is a part that becomes the upper part of the left side sill 14. Hereinafter, the upper part of the left side sill 14 is referred to as a “side sill upper part 82”.
The floor panel 16 is formed flat. Therefore, the floor panel 16 is disposed at the same height as the side sill upper portion 82. Thereby, when the passenger gets on and off, the left side sill 14 does not get in the way, and the passenger can get on and off satisfactorily.

A floor cross member 35 is provided on the upper surface 16 a of the floor panel 16. The floor cross member 35 includes a member upper portion 101, a member front wall portion 102, a member rear wall portion 103, a member front flange 104, and a member rear flange 105.
A member front wall portion 102 projects downward from the front side of the member upper portion 101 toward the floor panel 16. A member rear wall portion 103 projects downward from the rear side of the member upper portion 101 toward the floor panel 16. A floor cross member 35 is formed in a U-shaped cross section by the member upper portion 101, the member front wall portion 102, and the member rear wall portion 103.
The member front flange 104 projects from the lower side of the member front wall portion 102 toward the front of the vehicle body along the upper surface 16a of the floor panel 16. The member rear flange 105 protrudes from the lower side of the member rear wall 103 along the upper surface 16a of the floor panel 16 toward the rear of the vehicle body.

The member front flange 104 and the member rear flange 105 are joined to the upper surface 16 a of the floor panel 16, whereby the floor cross member 35 is attached to the upper surface 16 a of the floor panel 16. In this state, the member upper portion 101 of the floor cross member 35 is located above the side sill upper portion 82.
The floor cross member 35 has an inclined portion 107 on the left side sill 14 side. The member upper portion 101 has an upper inclined portion 108 in the vicinity of the left end portion.

  The upper inclined portion 108 is a portion that forms the upper portion of the inclined portion 107. The upper inclined portion 108 extends downward to the side sill upper portion 82 toward the outer side in the vehicle width direction. The outer end portion 108 a of the upper inclined portion 108 is located on the side sill upper portion 82. The end portion 104 a of the member front flange 104 and the end portion 105 a of the member rear flange 105 are joined to the side sill upper portion 82 via the left side portion 16 c of the floor panel 16. Therefore, the end portion 107 a of the inclined portion 107 is joined to the side sill upper portion 82 via the left side portion 16 c of the floor panel 16.

As shown in FIGS. 5 and 8, a gusset 62 is installed on the inner wall 81 of the inner bulging portion 76 of the side sill inner 66 and the lower surface 16 b of the floor panel 16. Hereinafter, the inner wall 81 of the inner bulging portion 76 is referred to as a “side sill inner wall 81”.
The gusset 62 includes a gusset inclined portion 111, a gusset front wall portion 112, a gusset rear wall portion 113, and gusset flanges 114 to 118. The gusset inclined portion 111 is formed in a rectangular shape in plan view. The gusset inclined portion 111 extends downward from the lower surface 16b of the floor panel 16 to the side sill inner wall 81 toward the outer side in the vehicle width direction. That is, the gusset 62 extends downward from the lower surface 16 b of the floor panel 16 to the side sill inner wall 81 toward the outer side in the vehicle width direction.

A gusset front wall portion 112 projects from the front side of the gusset inclined portion 111 toward the floor panel 16. A gusset rear wall portion 113 projects from the rear side of the gusset inclined portion 111 toward the floor panel 16. A gusset 62 is formed in a U-shaped cross section by the gusset inclined portion 111, the gusset front wall portion 112, and the gusset rear wall portion 113.
A gusset flange 114 projects from the lower side 111 a of the gusset inclined portion 111. Gusset flanges 115 and 116 are projected from the side 112a and the upper side 112b of the gusset front wall 112, respectively. Gusset flanges 117 and 118 project from the side 113a and the upper side 113b of the gusset rear wall 113, respectively.

A gusset flange 114 protruding from the lower side 111 a of the gusset inclined portion 111 is joined to a portion 81 a of the side sill inner wall 81 facing the inner bulkhead 56.
The gusset flange 115 protruding from the side 112 a of the gusset front wall 112 is joined to the side sill inner wall 81. A gusset flange 117 that protrudes from the side 113 a of the gusset rear wall 113 is joined to the side sill inner wall 81.
A gusset flange 116 protruding from the upper side 112 b of the gusset front wall 112 is joined to the lower surface 16 b of the floor panel 16. A gusset flange 118 protruding from the upper side 113 b of the gusset rear wall 113 is joined to the lower surface 16 b of the floor panel 16.

In this manner, the inclined portion 107 is formed on the floor cross member 35, and the upper inclined portion 108 of the inclined portion 107 is extended to the side sill upper portion 82 in a downward gradient toward the outer side in the vehicle width direction. Further, the gusset inclined portion 111 extends downward from the lower surface 16b of the floor panel 16 to the side sill inner wall 81 toward the outside in the vehicle width direction.
A cross section S <b> 1 is formed by the inclined portion 107 and the gusset 62. Further, the straight portion 35a of the floor cross member 35 is formed in the cross section S2. The cross section S1 is formed in substantially the same cross sectional shape as the cross section S2.

  Therefore, the strength of the inclined portion 107 is ensured similarly to the straight portion 35 a of the floor cross member 35. Thereby, when the impact load F <b> 1 is input from the side of the vehicle Ve, the load F <b> 3 can be transmitted from the inner bulkhead 56 to the gusset 62 through the side sill inner wall 81. The load F3 transmitted to the gusset 62 can be transmitted to the floor cross member 35, and the load F3 can be supported by the floor cross member 35.

  Furthermore, by providing the floor cross member 35 on the upper surface 16 a of the floor panel 16, the floor cross member can be removed from below the floor panel 16. Therefore, the space 119 below the floor panel 16 can be increased. Thereby, the capacity | capacitance of underfloor mounting components (namely, vehicle-mounted components), such as the battery pack 28 provided under the floor panel 16, can be increased. As a result, the capacity of the battery 123 accommodated in the battery pack 28 can be increased, and the cruising distance of the vehicle Ve can be increased.

Returning to FIG. 4, a battery pack 28 is provided between the left side sill 14 and the right side sill 15 (see FIG. 2) and below the floor panel 16. The battery pack 28 includes a battery case 121 and a lid 122. The battery case 121 includes a case wall portion 124, a case bottom portion 125, and a case flange 126.
The case wall portion 124 includes a front wall, a rear wall, a left side wall 124a, and a right side wall. The case wall 124 is formed in a rectangular frame shape by the front wall, the rear wall, the left side wall 124a, and the right side wall.

The case wall portion 124 is closed at the lower end portion by the case bottom portion 125 and has an opening 127 at the upper end portion. A case flange 126 projects from the entire periphery of the opening 127 of the case wall 124 to the outside of the battery case 121.
A battery cross member 131 is provided inside the battery case 121 (that is, inside the battery pack 28). The battery cross member 131 extends in the vehicle width direction inside the battery pack 28. The battery cross member 131 has a flange 131a at the left end. The flange 131 a is joined to the left side wall 124 a of the case wall portion 124.
In addition, a plurality of lower attachment portions 133a of the plurality of fastening members 133 are attached to the battery cross member 131 with bolts and nuts at intervals in the vehicle width direction. A battery 123 is housed inside the battery case 121.

An opening 127 of the battery case 121 is closed from above by a lid 122. The lid 122 includes a lid wall portion 135, a lid top portion 136, and a lid flange 137.
The lid wall part 135 has a front wall, a rear wall, a left side wall 135a, and a right side wall. A lid wall portion 135 is formed in a rectangular frame shape by the front wall, the rear wall, the left side wall 135a, and the right side wall. That is, the lid wall portion 135 is formed in the same manner as the case wall portion 124.
The lid wall portion 135 is closed at the upper end portion by the lid top portion 136, and an opening portion 138 is formed at the lower end portion. A lid flange 137 projects from the entire periphery of the opening 138 of the lid wall portion 135 to the outside of the lid 122.

By overlapping the lid flange 137 on the case flange 126 from above, the gap between the lid flange 137 and the case flange 126 is sealed with a seal member. Therefore, the opening 127 of the battery case 121 is closed with the lid 122. A battery 123 is accommodated in the interior 129 of the battery pack 28. In a state where the opening 127 of the battery case 121 is closed with the lid 122, the upper portion 133 b of the fastening member 133 protrudes upward from the opening 136 a of the lid top portion 136.
The protruding upper portion 133b is fastened to the bracket 141 of the floor cross member 35 with bolts and nuts. Thereby, the battery pack 28 is fastened to the bracket 141 of the floor cross member 35 by the plurality of fastening members 133.

As shown in FIGS. 5 and 9, the battery pack 28 is disposed inside the left side sill 14 in the vehicle width direction. The battery pack 28 is provided at a predetermined interval L1 with respect to the side sill inner wall 81.
A battery pack frame 29 is attached to the left side wall 124a of the case wall portion 124 (the outer periphery of the battery pack 28). The battery pack frame 29 is formed in an L-shaped cross section. The battery pack frame 29 includes a fixing portion 143 and a frame main body 144.

The fixing portion 143 is attached to the lower portion (lower surface) 83 of the inner bulging portion 76. A lower portion 83 of the inner bulging portion 76 is a portion that becomes a lower portion of the left side sill 14. Hereinafter, the lower part of the left side sill 14 is referred to as a “side sill lower part 83”.
The frame main body 144 is raised from the fixed portion 143 toward the side sill inner wall 81 and is disposed so as to face the inner bulkhead 56 through the side sill inner wall 81.

The frame main body 144 includes an inner wall portion 146, an outer wall portion 147, a top portion 148, a bottom portion 149, and a lower flange 151. A frame main body 144 is formed in a rectangular frame shape by the inner wall portion 146, the outer wall portion 147, the top portion 148, and the bottom portion 149.
The inner wall portion 146 of the frame main body 144 is joined along the left side wall 124 a of the case wall portion 124. Furthermore, the inner wall portion 146 is also joined to the flange 131a of the battery cross member 131 via the left side wall 124a. That is, the frame body 144 is joined to the battery cross member 131.
The lower flange 151 is joined along the case bottom 125 of the battery case 121. A bulkhead 152 is attached inside the frame body 144.

The fixing part 143 includes a top part 154, an outer wall part 155, a bottom part 156, a bent part 157, an upper flange 158, and a lower flange 159. A fixing portion 143 is formed in a U-shaped cross section at the top portion 154, the outer wall portion 155, and the bottom portion 156. The upper flange 158 is joined along the outer wall portion 147 of the frame main body 144. The lower flange 159 is joined along the lower flange 151 of the frame body 144.
A collar 162 is interposed in the interior 161 of the fixing portion 143, and a bolt 163 is passed through the collar 162. The fixing portion 143 is attached to the side sill lower portion 83 with a bolt 163 and a nut 164.

  As described above, the fixing portion 143 is attached to the side sill lower portion 83, and the frame main body 144 of the battery pack frame 29 is raised toward the side sill inner wall 81. The frame main body 144 is opposed to the inner bulkhead 56 via the side sill inner wall 81. The frame main body 144 is joined to the flange 131a of the battery cross member 131.

  Therefore, when the impact load F1 is input from the side of the vehicle Ve, the load F4 is transmitted from the left side sill 14 to the battery cross member 131 through the fixing portion 143 and the frame main body 144, and the load F4 is supported by the battery cross member 131. be able to. Further, the impact load F1 input from the side of the vehicle Ve is transmitted from the inner bulkhead 56 to the frame main body 144 and the battery cross member 131 through the side sill inner wall 81, and the load F5 is supported by the battery cross member 131. it can.

Thus, the outer bulkhead 52 and the inner bulkhead 56 can be sufficiently crushed by the impact load F1 to absorb the impact energy well, and the battery 123 housed in the interior 129 of the battery pack 28 can be protected from the impact load F1.
Further, by supporting the load F4 and the load F5 with the battery cross member 131, the fixing portion 143 and the frame main body 144 (that is, the battery pack frame 29) can be crushed. Thereby, impact energy can be absorbed better and the battery 123 can be protected from the impact load F1.

As described above, according to the vehicle body lower structure 12, the joint flanges 86 and 93 of the outer bulkhead 52 and the inner bulkhead 56 are joined to each other via the stiffener 67. Therefore, the box shape of the outer bulkhead 52 is restrained by the joint flange 86. Further, the box-like shape of the inner bulkhead 56 is restrained by the joining flange 93.
Thereby, when the impact load F1 is input from the side of the vehicle Ve, the impact load F1 is transmitted to the entire side wall 84 of the outer bulkhead 52 (that is, the entire circumference). Further, the impact load F1 is transmitted to the entire area of the side wall 91 of the inner bulkhead 56 (that is, the entire circumference). As a result, the entire circumference of the side wall 84 of the outer bulkhead 52 and the entire circumference of the side wall 91 of the inner bulkhead 56 can be buckled by the impact load F1, and the impact energy can be absorbed.

  Here, the battery pack 28 is mounted inside the left side sill 14 in the vehicle width direction. In this case, by absorbing the impact load F1 input from the side of the vehicle Ve by the outer bulkhead 52 and the inner bulkhead 56, the battery 123 in the battery pack 28 can be protected from the impact load F1.

Further, the outer bulkhead 52 is disposed on the outer side in the vehicle width direction of the stiffener 67, and the inner bulkhead 56 is disposed on the inner side in the vehicle width direction of the stiffener 67. That is, the outer bulkhead 52 and the inner bulkhead 56 are arranged side by side in the vehicle width direction. Therefore, the outer bulkhead 52 and the inner bulkhead 56 can be provided inside the left side sill 14 without increasing the height of the left side sill 14.
Thereby, the height of the left side sill 14 can be suppressed, and the left side sill 14 does not get in the way when the occupant gets in and out, so that the occupant can get in and out easily.

Next, an example in which the battery 123 is protected by the vehicle body lower structure 12 when an impact load F6 is input from the side of the vehicle Ve will be described with reference to FIG.
As shown in FIG. 10, an impact load F6 is input to the left side sill 14 from the side of the vehicle Ve. The outer bulging portion 71 of the side sill outer 65 of the left side sill 14 is deformed inward in the vehicle width direction by the impact load F6 input to the left side sill. The outer bulging portion 71 is deformed and comes into contact with the bottom 85 of the outer bulkhead 52.

The joining flanges 86 and 93 of the outer bulk head 52 and the inner bulk head 56 are joined to each other via a stiffener 67. Therefore, the box shape of the outer bulkhead 52 is restrained by the joint flange 86. Further, the box-like shape of the inner bulkhead 56 is restrained by the joining flange 93.
Thereby, the impact load F <b> 6 is transmitted to the entire side wall 84 (that is, the entire circumference) of the side wall 84 of the outer bulkhead 52 by coming into contact with the bottom portion 85 of the outer bulkhead 52. Further, the impact load F6 is transmitted to the entire area of the side wall 91 of the inner bulkhead 56 (that is, the entire circumference).
Due to the impact load F6, the entire circumference of the side wall 84 of the outer bulkhead 52 and the entire circumference of the side wall 91 of the inner bulkhead 56 are crushed by the impact load F6 to absorb impact energy.

  The remaining load absorbed by the outer bulkhead 52 and the inner bulkhead 56 is transmitted to the floor cross member 35 as a load F7. Further, the remaining load is transmitted as the load F8 to the battery cross member 131 through the fixing portion 143 and the frame main body 144. Further, the remaining load is transmitted to the battery cross member 131 via the frame body 144 as a load F9.

The load F7 is supported by the floor cross member 35. The loads F8 and F9 are supported by the battery cross member 131. Therefore, the outer bulk head 52 and the inner bulk head 56 can be sufficiently crushed, and the impact energy due to the impact load F 6 can be absorbed well by the outer bulk head 52 and the inner bulk head 56.
Further, by supporting the load F8 and the load F9 with the battery cross member 131, the fixing portion 143 and the frame main body 144 (that is, the battery pack frame 29) can be crushed. Therefore, the load F8 and the load F9 can be favorably absorbed by the battery pack frame 29.
Thereby, the battery 123 accommodated in the interior 129 of the battery pack 28 can be protected from the impact load F6.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, an example in which the outer bulkhead 52 and the inner bulkhead 56 are formed in a box shape with a rectangular cross section has been described, but the present invention is not limited thereto. As another example, the outer bulkhead 52 and the inner bulkhead 56 can be formed in a box shape having a polygonal cross section such as a pentagon or a hexagon.

  Moreover, although the said embodiment demonstrated the example which formed the hole part 96 in the stiffener 67, it is not restricted to this. As another example, the hole 96 may be removed from the stiffener 67. By removing the hole 96 from the stiffener 67, the rigidity of the vehicle body can be improved and the amount of impact energy absorbed can be increased.

  Furthermore, in the said embodiment, although the battery pack 28 of the underfloor mounting component was illustrated as a vehicle-mounted component, it is not limited to this. It is also possible to apply to other parts, such as a fuel tank, as other vehicle-mounted parts.

Ve ......... Vehicle 10 ......... Body 12 ......... Body lower structure 14,15 ... Left and right side sills (side sills)
16 ......... Floor panel 16a ... Floor panel upper surface 16b ... Floor panel lower surface 28 ......... Battery pack 29 ......... Battery pack frame 31 ......... Driver seat (seat)
32 ... Passenger seat (sheet)
34-36 ... 1st-3rd floor cross member (floor cross member)
51-53 ... 1st-3rd outer bulkhead (outer bulkhead)
55-57 ... 1st-3rd inner bulkhead (inner bulkhead)
61-63 ... 1st-3rd gusset (gusset)
65 ……… Side sill outer 66 ……… Side sill inner 67 ……… Stiffener 81 ……… Side sill inner wall (inside wall of side sill)
81a ... Side sill inner wall facing the inner bulkhead 82 ... ... Side sill top (upper side sill)
83 ......... Lower side sill (lower side sill)
84, 91 ... Side wall 85, 92 ... Bottom 86, 93 ... Joint flange 87, 94 ... Opening 96 ......... Hole 101 ... Member upper part 107 ... Inclined part 108 ... Upper inclined part 121 ... Case 123 ... … Battery 124 …… Case wall (Battery pack side wall)
124a ... left side wall (side wall of battery pack)
129 …… Inside of battery pack 131 …… Battery cross member 143 …… Fixing part 144 …… Frame body L1 ……… Predetermined interval

Claims (6)

A side sill with a stiffener sandwiched between the side sill outer and the side sill inner;
An outer bulkhead disposed between the side sill outer and the stiffener and attached to the stiffener;
An inner bulkhead disposed between the side sill inner and the stiffener and attached to the stiffener;
The outer bulkhead and the inner bulkhead are
Formed in a box shape with a polygonal cross section with an opening on the stiffener side,
A side wall extending in a direction away from the stiffener;
A bottom for closing one end of the side wall away from the stiffener;
A joining flange joined to the other end on the opening side of the side wall via the stiffener,
The vehicle body lower structure characterized by having. The side sill is provided on both sides of the vehicle body,
A floor cross member erected between the side sills in the vehicle width direction,
The outer bulkhead and the inner bulkhead are provided so as to overlap the floor cross member in the vehicle width direction.
The vehicle body lower part structure according to claim 1. At least a pair of the floor cross members are provided at intervals in the longitudinal direction of the vehicle body,
A seat is attached to a pair of floor cross members,
The vehicle body lower part structure according to claim 2, wherein: A floor panel attached to an upper portion of the side sill and provided with the floor cross member on an upper surface;
A gusset that is installed on the inner wall of the side sill and the lower surface of the floor panel, and extends downwardly from the lower surface toward the outer side in the vehicle width direction,
The gusset is attached to a portion of the inner wall facing the inner bulkhead,
The floor cross member has a member upper part located above the upper part of the side sill,
The upper part of the member has an upper inclined part that extends downward toward the vehicle width direction outside to the upper part of the side sill,
The vehicle body lower structure according to claim 2, wherein the lower body structure is a vehicle body lower structure. A battery pack that is provided at a predetermined interval on the inner side in the vehicle width direction of the side sill, and stores a battery;
A battery cross member provided in the battery pack and extending in the vehicle width direction;
A battery pack frame attached to a side wall of the battery pack,
The battery pack frame is
A fixing portion attached to a lower portion of the side sill;
A frame main body raised from the fixing portion toward the inner wall of the side sill, facing the inner bulkhead via the inner wall, and attached to the battery cross member via the side wall of the battery pack; Prepared,
The vehicle body lower part structure according to any one of claims 1 to 4, wherein the vehicle body lower part structure is provided. The stiffener is
Having a hole formed in a portion corresponding to the opening of the outer bulkhead and the inner bulkhead;
The vehicle body lower structure according to any one of claims 1 to 5, wherein

Images