CN113015671A - Vehicle body structure - Google Patents

Abstract

A vehicle body structure (10) is provided with a vehicle underbody skeleton frame (12), a battery mounting frame (13), and a subframe (15). The vehicle body bottom framework frame is formed annularly along the periphery of the bottom plate. The battery mounting frame is formed in a ring shape and fixed to the underbody frame. The sub-frame is provided in front of the battery mounting frame. The subframe is provided with a deformation facilitating portion which is provided at the front of a vehicle body and fixed to a rear mounting portion (77) of the underbody frame. The battery mounting frame includes a stopper portion facing the rear mounting portion of the subframe.

Description

Vehicle body structure

Technical Field

The present invention relates to a vehicle body structure.

The present application claims priority based on japanese patent application No. 2018-216642, filed on 11/19/2018, the contents of which are incorporated herein by reference.

Background

As a vehicle body structure, for example, a structure is known in which impact energy generated by a front collision is absorbed by deformation of a front side frame to reduce deceleration applied to a passenger. In this vehicle body structure, a sub-frame for supporting a power unit such as an engine and a suspension is disposed below the front side frame. Therefore, the rear end portion of the subframe and the split member of the subframe are rotated around the fulcrum of the base frame and are simultaneously detached at the time of the front collision, thereby preventing the deformation of the front side frame from being hindered by the subframe. This ensures the collision deformation amount (energy absorption stroke), and deforms the front side frame to absorb the impact energy (see, for example, patent document 1).

In addition, as a vehicle body structure, there is known a structure in which a rear portion of a subframe is fixed to a mounting portion between a rear portion of a front side frame and a bottom frame, and a stopper portion is provided behind the mounting portion. This vehicle body structure absorbs impact energy generated by a front collision by bending the subframe downward. Further, when the subframe is bent downward to absorb the impact energy, a load is transmitted from the rear portion of the subframe to the stopper portion, and the load is dispersed to the rear portion of the front side frame and the bottom frame (see, for example, patent document 2).

Prior art documents

Patent document

Patent document 1: japanese patent No. 5557925

Patent document 2: japanese patent No. 4622284

Disclosure of Invention

Problems to be solved by the invention

Here, for example, an electric vehicle (so-called EV) is equipped with an impact-intolerant battery (IPU: intelligent power unit) under the floor of the vehicle. Therefore, in the vehicle body structure of patent document 1, it is considered that the rear end portion of the subframe interferes with the battery at the rear of the vehicle body when the rear end portion of the subframe and the partition member of the subframe rotate about the fulcrum of the underframe. In order to ensure the collision deformation amount, it is necessary to make a study to detach the rear end portion of the subframe while preventing interference with the battery due to the rear end portion of the subframe.

In addition, the electric vehicle has a heavy battery (IPU) mounted under the floor, and thus the weight of the vehicle is increased. Thus, in order to increase the collision energy absorbed by the subframe, the load distribution of the subframe needs to be increased. Therefore, with the vehicle body structure of patent document 2, it is necessary to increase the strength of the vehicle body members (i.e., the mounting portions, the rear portions of the front side frames, the under frame) for receiving the input load of the sub frame, which leads to an increase in the vehicle body weight, thus being disadvantageous in suppressing the fuel consumption rate.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle body structure capable of ensuring a collision deformation amount without increasing the vehicle body weight.

Means for solving the problems

In order to solve the above problems, the present invention adopts the following aspects.

(1) A vehicle body structure according to an aspect of the present invention includes: an annular underbody skeleton frame formed along an outer periphery of the floor panel; an annular battery mounting frame fixed to the underbody skeleton frame; and a sub-frame provided in front of the vehicle body of the battery mounting frame, the sub-frame including a deformation facilitating portion provided in front of the vehicle body fixed to a rear mounting portion of the underbody skeleton frame, the battery mounting frame including a stopper portion opposed to the rear mounting portion of the sub-frame.

In this way, the subframe is provided with the easy-to-deform portion, and the stopper portion of the battery mounting frame is opposed to the rear mounting portion of the subframe. Thus, the rear mounting portion can be brought into contact with the stopper portion by an impact load generated by a front collision, and the easily deformable portion of the subframe can be deformed. This ensures the collision deformation amount, and absorbs the impact energy generated by the front collision.

Further, the stopper portion can support the rear mounting portion of the subframe that moves rearward of the vehicle body. This makes it possible to disperse the impact load generated by the front collision to the underbody frame and the battery mounting frame. Thus, the cross-sectional shape and the thickness dimension of the underbody skeleton frame can be reduced, and the vehicle body structure can be made lightweight.

Further, by forming the underbody skeleton frame and the battery mounting frame in an annular shape, the strength and rigidity of each frame can be improved. Further, the frames are formed in substantially the same outline to fix the battery mounting frame to the underbody skeleton frame. Thus, the battery mounting frame can compensate for the function of the underbody skeleton frame, and the vehicle body structure can be further reduced in weight.

Further, by forming the battery mounting frame in an annular shape, the outer periphery of the battery can be surrounded in all directions by the battery mounting frame. Thus, the battery can be sufficiently protected from external impact by the battery mounting frame.

(2) In the above aspect (1), the sub-frame may be provided with a steering mechanism on a vehicle body front side, and the deformation facilitating portion may be provided between the steering mechanism and the rear mounting portion of the sub-frame.

In this way, the easy-to-deform portion is provided between the steering mechanism and the rear mounting portion of the subframe. Thus, when the sub frame is deformed at the easily deformable portion by an impact load generated by a front collision and the steering mechanism is moved rearward of the vehicle body, the sub frame can be prevented from being sandwiched between the sub frame and the dash lower panel, and the sub frame can be sufficiently crushed. Thus, the front side frame can be sufficiently crushed, and therefore a sufficient amount of collision deformation (energy absorption stroke) can be obtained without detaching the rear mounting portion of the subframe from the vehicle body.

(3) In addition to the above-described aspect (1) or (2), the easily deformable portion of the subframe may be formed of at least three bent portions.

Thus, the easy-to-deform portion is formed by at least three bent portions. Thus, a large amount of impact energy absorption can be obtained by causing the sub frame to buckle and deform in a corrugated shape in a side view at the deformation-prone portion due to the impact load generated by the front collision.

Further, by causing the subframe to buckle and deform in a corrugated shape, the pressing force for moving the rear mounting portion rearward of the vehicle body can be made larger than the rotational force acting on the rear mounting portion. This ensures a large contact surface between the rear mounting portion and the stopper portion. This makes it possible to transmit the impact load from the rear mounting portion to the stopper portion satisfactorily and receive the impact load satisfactorily by the stopper portion (i.e., the battery mounting frame).

(4) In addition to the above aspect (3), the rear mounting portion of the subframe may be provided with a reinforcing plate that overlaps a vehicle body rear mounting surface of a rearmost bent portion of the bent portions.

In this way, by providing the reinforcement panel at the rear of the vehicle body at the rearmost bent portion, the rear attachment portion can be reinforced by the reinforcement panel. This can promote deformation of the bent portion (i.e., the subframe) due to an impact load generated by a front collision.

(5) In addition to any one of the above aspects (1) to (4), the battery mounting frame includes: a vehicle body mounting portion provided on an outer side and mounted to the vehicle body bottom skeleton frame; and a recessed portion provided in the vehicle body mounting portion and formed in a recessed shape toward an inner side, the rear mounting portion of the subframe being disposed in the recessed portion.

In this way, the vehicle body mounting portion is provided on the outer side of the battery mounting frame, and the recess portion is provided in the vehicle body mounting portion. Further, a rear mounting portion of the subframe is disposed in the recess. Thus, the distance between the rear mounting portion and the stopper portion can be reduced by bringing the rear mounting portion of the subframe close to the battery mounting frame (specifically, the stopper portion). Thus, the rear mounting portion of the subframe is moved rearward of the vehicle body by the impact load generated by the frontal collision, so that the rear mounting portion can be quickly brought into contact with the stopper portion and the stopper portion can receive the impact load satisfactorily.

(6) In addition to any one of the above-described aspects (1) to (5), the rear mounting portion of the subframe may be fixed to a position rearward of the vehicle body with respect to a center of gravity of the underbody frame.

Here, the vehicle underbody skeleton frame is tilted toward the battery mounting frame side with the center of gravity as the center by the impact load generated by the front collision.

Therefore, the design is made as follows: the rear mounting portion of the sub-frame is fixed to a position behind the vehicle body with respect to the center of gravity of the underbody skeleton frame. As a result, the rear mounting portion of the subframe can be brought into contact with the front surface (i.e., stopper portion) of the battery mounting frame quickly and reliably, and the impact load can be quickly transmitted to the battery mounting frame.

(7) In addition to the above aspect (5), the vehicle underbody skeleton frame may be formed in an octagonal ring shape in a plan view, and the battery mounting frame may include an octagonal ring-shaped skeleton portion in a plan view and be fixed to each side of the vehicle underbody skeleton frame.

In this way, the vehicle underbody skeleton frame is formed in an octagonal ring shape, and the ring-shaped skeleton portion of the battery mounting frame is formed in an octagonal ring shape. Further, the annular frame portion of the battery mounting frame is fixed to the underbody frame. As a result, the impact load due to the collision can be received by the under frame and the annular frame portion from the vehicle body front-rear direction, the vehicle width direction (i.e., the left-right direction), the vehicle body front oblique direction, and the vehicle body rear oblique direction. This makes it possible to protect the battery against an impact load inputted from the vehicle body in all directions.

(8) In the above aspect (7), the annular skeleton portion of the battery mounting frame may have an outer peripheral portion formed by at least an upper wall, a lower wall, and a vertical wall connecting the upper wall and the lower wall, and the vehicle body mounting portion may be integrally provided on the vertical wall.

In this way, the vehicle body mounting portion is formed in the annular frame portion of the battery mounting frame.

The vehicle body mounting portion is provided with a recess. Thus, it is not necessary to form a recess in the annular frame portion, and the recess can be formed without affecting the strength and rigidity of the battery mounting frame.

(9) In the above-described aspect (5) or (8), a space may be formed between the vehicle body mounting portion of the battery mounting frame and the underbody skeleton frame.

In this way, a space is formed between the vehicle body mounting portion of the battery mounting frame and the underbody skeleton frame. This makes it possible to make the rear mounting portion enter the space when the rear mounting portion of the subframe moves rearward of the vehicle body due to an impact load generated by a front collision. This allows the rear mounting portion to abut against the annular frame portion of the battery mounting frame to transmit the impact load.

Further, the rear mounting portion of the subframe is inserted into the space, whereby the subframe can be moved along the upper side of the vehicle body mounting portion of the battery mounting frame. This prevents the fastening bolts (fastening members) that attach the rear attachment portion of the subframe to the underbody frame from falling off from the vehicle body attachment portion.

(10) In any one of the above aspects (1) to (9), the subframe is formed such that a cross section of a front portion is larger than a cross section of a rear portion, and includes a receiving member that protrudes outward in the vehicle width direction from the front portion to receive an impact load generated by a narrow offset collision.

In this way, the receiving member is provided at the front portion of the subframe so as to project outward in the vehicle width direction. This makes it possible to absorb the impact load (energy) due to the plane collision (full-circle frontal collision) and also the impact energy due to the narrow offset collision.

Effects of the invention

According to the aspect of the present invention, the sub-frame is provided with the easy-to-deform portion, and the stopper portion of the battery mounting frame is opposed to the rear mounting portion of the sub-frame. Further, the stopper portion supports a rear mounting portion of the subframe that moves rearward of the vehicle body. This ensures the amount of collision deformation without increasing the weight of the vehicle body.

Drawings

Fig. 1 is a bottom view of a vehicle body structure according to a first embodiment of the present invention as viewed from below.

Fig. 2 is a perspective view of a main portion of the vehicle body structure of the first embodiment as viewed from below.

Fig. 3 is a bottom view showing a state in which the steering mechanism and the lower arm are provided in the vehicle body structure of the first embodiment.

Fig. 4 is a sectional view taken along line IV-IV of fig. 1.

Fig. 5 is a cross-sectional view taken along line V-V of fig. 1.

Fig. 6 is a perspective view of the subframe detached from the vehicle body structure of the first embodiment.

Fig. 7 is a side view of the vehicle body structure of the first embodiment as viewed from the left side.

Fig. 8 is a perspective view showing a subframe according to the first embodiment.

Fig. 9 is a perspective view of the vehicle body structure of the first embodiment in a state where the steering mechanism and the lower arm are provided.

Fig. 10 is a cross-sectional view taken along line X-X of fig. 1.

Fig. 11 is an enlarged cross-sectional view of section XI of fig. 10.

Fig. 12 is a perspective view of the vehicle body structure of the first embodiment in a state where the steering mechanism and the lower arm are provided.

Fig. 13A is a side view illustrating an example of inputting an impact load to the vehicle body structure of the first embodiment.

Fig. 13B is a side view illustrating an example of absorption of an impact load by the vehicle body structure of the first embodiment.

Fig. 14 is a side view illustrating an example of deformation of the subframe according to the first embodiment due to an impact load.

Fig. 15 is a bottom view of the vehicle body structure according to the second embodiment of the present invention as viewed from below.

Fig. 16 is a perspective view showing an annular skeleton portion of a vehicle body structure according to a third embodiment of the present invention.

Fig. 17 is a side view of the vehicle body structure according to the fourth embodiment of the present invention as viewed from the left side.

Fig. 18 is a side view illustrating an example in which the rear mounting portion of the subframe of the fourth embodiment is brought into contact with the stopper portion to transmit the impact load.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, arrow FR indicates the front of the vehicle, arrow UP indicates the upper side of the vehicle, and arrow LH indicates the left side of the vehicle. The vehicle body structure 10 is a substantially bilaterally symmetric structure, and hereinafter, for convenience, the left and right constituent members will be described with the same reference numerals.

(first embodiment)

As shown in fig. 1 to 3, the vehicle body structure 10 includes an underbody frame 12, a battery mounting frame 13, left and right front side frames 14, a sub-frame 15, a front impact beam 16, a steering mechanism 17 (see also fig. 9), and a lower arm 18 (see also fig. 9).

The vehicle body bottom frame 12, the left and right front side frames 14, and the front impact beam 16 are members that constitute the framework of the vehicle body. The vehicle body structure 10 is employed in, for example, an electric vehicle (so-called EV) or the like.

The underbody skeleton frame 12 is formed in an octagonal ring shape in a plan view along the outer periphery of the floor portion (outer periphery of the floor panel) of the vehicle body. The vehicle underbody frame 12 includes left and right rocker beams 21, left and right outriggers (front side frame end portions) 22, a front cross member 23, left and right rear frame front portions 24a, and a rear cross member 25.

The left and right rocker members 21 are provided at left and right outer lower portions of the vehicle interior with a gap therebetween in the vehicle width direction of the vehicle body structure 10, and extend in the vehicle body front-rear direction. The left and right side sills 21, 21 are high-rigidity members that are formed into a rectangular closed cross section, for example, and that form a vehicle body frame.

The rear end 22a of the left outrigger 22 is connected to the front end 21a of the left rocker 21. The left arm 22 extends obliquely from the rear end 14a of the left front side frame 14 toward the vehicle body rear and to the vehicle width direction left outer side to the front end 21a of the left rocker 21.

A rear end portion 22a of the right outrigger 22 is connected to a front end portion 21a of the right rocker 21. The right outrigger 22 extends obliquely from the rear end portion 14a of the right front side frame 14 toward the vehicle body rear and the vehicle width direction right outer side to the front end portion 12a of the right rocker 21. The left and right cantilevers 22 are high-rigidity members having a rectangular closed cross section and forming a vehicle body frame, for example.

The front cross member 23 is erected on the left and right outriggers 22, 22 toward the vehicle width direction. The front cross member 23 is a highly rigid member formed into a hat shape in section (see fig. 11), for example, and forms a vehicle body frame. The center of gravity G1 (see fig. 11) of the front cross member 23 is located at substantially the center of the hat-shaped cross section.

The left rear frame 24 extends from the rear end portion 21b of the left rocker 21 toward the vehicle body rear to the rear end portion of the vehicle body structure 10. The left rear frame 24 has a left rear frame front portion 24a coupled to the rear end portion 21b of the left rocker 21. The left rear frame front portion 24a extends obliquely rearward of the vehicle body and rightward inward in the vehicle width direction from the rear end portion 21b of the left rocker 21.

Further, the right rear frame 24 extends from the rear end portion 21b of the right rocker 21 toward the vehicle body rear to the rear end portion of the vehicle body structure 10. The right rear frame 24 has a right rear frame front portion 24a coupled to the rear end portion 21b of the right rocker 21. The right rear frame front 24a extends obliquely rearward of the vehicle body and to the left inner side in the vehicle width direction from the rear end portion 21b of the left rocker 21. The left and right rear frame front portions 24a, 24a are high-rigidity members that are formed into a rectangular closed cross section, for example, and that form a vehicle body frame.

The rear cross member 25 is bridged between the rear end portion 24b of the left rear frame front portion 24a and the rear end portion 24b of the right rear frame front portion 24a in the vehicle width direction. The rear cross member 25 is a highly rigid member forming a vehicle body frame, for example, formed in a hat-shaped cross section, similarly to the front cross member 23.

The vehicle underbody skeleton frame 12 is formed in an octagonal ring shape in plan view by the left and right rocker beams 21, the left and right outriggers 22, the front cross member 23, the left and right rear frame front portions 24a, and the rear cross member 25. A floor panel 27 (see fig. 4) is provided inside the underbody skeleton frame 12. The floor portion of the vehicle compartment is formed by the floor panel 27.

Here, the left and right rocker beams 21, the left and right outriggers 22, the front cross member 23, the left and right rear frame front portions 24a, and the rear cross member 25 are highly rigid members that form the vehicle body frame. That is, the vehicle underbody skeleton frame 12 is formed in an octagonal ring shape by a vehicle body skeleton member having high rigidity.

The battery mounting frame 13 is fixed to the underbody frame 12 by a plurality of fastening bolts (fastening members) 31.

The battery mounting frame 13 is formed in an octagonal ring shape along the underbody skeleton frame 12. The battery mounting frame 13 has a lower portion covered with a battery bottom plate 32 from below, and a driving battery (IPU: intelligent power unit) 34 (see fig. 4) is mounted inside. In the embodiment, an example in which the battery 34 for driving is mounted inside the battery mounting frame 13 is described, but the present invention is not limited to this.

The battery mounting frame 13 includes an annular frame portion 36 and a vehicle body mounting portion 37.

The annular skeleton portion 36 and the vehicle body attachment portion 37 are formed in an octagonal annular shape in plan view along the underbody skeleton frame 12.

As shown in fig. 4 and 5, the annular frame portion 36 includes a frame upper wall (upper wall) 41, a frame lower wall (lower wall) 42, an outer vertical wall (vertical wall) 43, and an inner vertical wall 44. The framework upper wall 41 is disposed below the bottom plate 27 along the bottom plate 27. The lower skeleton wall 42 is disposed below the upper skeleton wall 41 along the upper skeleton wall 41. An outer vertical wall 43 is connected to the outer periphery of the upper skeleton wall 41 and the outer periphery of the lower skeleton wall 42. An inner vertical wall 44 is connected to the inner periphery of the upper skeleton wall 41 and the inner periphery of the lower skeleton wall 42.

The outer peripheral portion 38 of the annular frame portion 36 is formed in a U-shaped cross section by a frame upper wall 41, a frame lower wall 42, and an outer vertical wall 43. The annular frame portion 36 is formed by a hollow frame having a rectangular cross section by the frame upper wall 41, the frame lower wall 42, the outer vertical wall 43, and the inner vertical wall 44. That is, the annular frame portion 36 is a highly rigid frame member formed of a hollow frame having a rectangular cross section.

A vehicle body mounting portion 37 is provided outside the annular skeleton portion 36. That is, the battery mounting frame 13 is provided with a vehicle body mounting portion 37 on the outer side. The vehicle body attachment portion 37 is formed in an octagonal ring shape in a plan view along an outer peripheral portion 38 of the annular skeleton portion 36 (see fig. 1). The vehicle body mounting portion 37 includes a mounting upper wall 46, a mounting lower wall 47, and a mounting outer peripheral wall 48. The attachment upper wall 46 projects from the center of the skeleton upper wall 41 in the vertical direction toward the outside of the annular skeleton portion 36. The lower attachment wall 47 is disposed below the upper attachment wall 46 and extends from the lower bobbin wall 42 along the upper attachment wall 46 toward the outside of the annular bobbin portion 36. A mounting outer peripheral wall 48 is joined to an outer periphery of the mounting upper wall 46 and an outer periphery of the mounting lower wall 47.

The vehicle body attachment portion 37 is formed in a U-shaped cross section by an attachment upper wall 46, an attachment lower wall 47, and an attachment outer peripheral wall 48. The vehicle body mounting portion 37 is integrally provided on the outer vertical wall 43 (outer peripheral portion 38) and is disposed below the vehicle underbody skeleton frame 12. The mounting upper wall 46 of the vehicle body mounting portion 37 is fixed to each side of the vehicle underbody skeleton frame 12 from below by a plurality of fastening coupling bolts 31.

As shown in fig. 1, each side of the vehicle underbody skeleton frame 12 is constituted by left and right rocker beams 21, left and right outriggers 22, a front cross member 23, left and right rear frame front portions 24a, and a rear cross member 25.

That is, the vehicle body attachment portion 37 includes left and right side attachment portions 51, left and right front oblique attachment portions 52, a front attachment portion 53, left and right rear oblique attachment portions 54, and a rear attachment portion 55 as attachment portions corresponding to the respective sides.

Returning to fig. 4, the front mounting portion 53 is attached to the outer peripheral portion 38 of the front skeleton portion 45 in the annular skeleton portion 36. The front frame portion 45 extends in the vehicle width direction along the front cross member 23 while being arranged at a portion of the annular frame portion 36 that is located rearward of the vehicle body of the front cross member 23. The front frame portion 45 is disposed at a position facing left and right rear mounting portions 77 (described later) of the subframe 15, and also serves as a stopper portion for the left and right rear mounting portions 77. Hereinafter, the front skeleton portion 45 will be described as the stopper portion 45.

The reason why the anterior bone portion 45 also serves as the stopper portion 45 will be described in detail later.

As shown in fig. 2 and 6, the front attachment portions 53 are disposed at positions facing the left and right rear attachment portions 77 of the subframe 15. The left and right mounting end portions 53a, 53b of the front mounting portion 53 are fixed to the front cross member 23. Specifically, the left mounting end portion 53a is a portion of the front mounting portion 53 that is offset to the left end, and is mounted to the left end portion 23a of the front cross member 23 by a pair of fastening bolts 31. The pair of fastening bolts 31 of the left mounting end portion 53a are disposed at intervals in the vehicle width direction.

The right mounting end portion 53b is a portion of the front mounting portion 53 that is offset to the right end, and is mounted to the right end portion 23b of the front cross member 23 by a pair of fastening bolts 31. The pair of fastening bolts 31 of the right mounting end portion 53b are disposed at intervals in the vehicle width direction.

The front mounting portion 53 is fixed to the front cross member 23 by attaching the left mounting end portion 53a to the left end portion 23a of the front cross member 23 and attaching the right mounting end portion 53b to the right end portion 23b of the front cross member 23.

The left mounting end portion 53a has a left recess (recess) 57 formed between the pair of fastening bolts 31. The left recess 57 is formed in a concave shape by being cut away in a curved shape from the mounting outer peripheral wall 48 of the left mounting end portion 53a toward the annular skeleton portion 36 (i.e., the vehicle body rear side), for example.

The right attachment end portion 53b is formed with a right recess (recess) 58 between the pair of fastening bolts 31, similarly to the left recess 57. The right recessed portion 58 is formed in a recessed shape by being cut away in a curved shape from the mounting outer peripheral wall 48 of the right mounting end portion 53b toward the annular skeleton portion 36 (i.e., the vehicle body rear side), for example, similarly to the left recessed portion 57.

In this way, the vehicle body mounting portion 37 is formed in the annular skeleton portion 36 of the battery mounting frame 13, and the left recess 57 and the right recess 58 are provided in the front mounting portion 53 of the vehicle body mounting portion 37. Thus, the left recess 57 and the right recess 58 do not need to be formed in the annular frame portion 36, and the left recess 57 and the right recess 58 can be formed without affecting the strength and rigidity of the battery mounting frame 13.

In the embodiment, the example in which the left and right concave portions 57 and 58 are formed in the curved shape has been described, but the shape of the left and right concave portions 57 and 58 is not limited to the curved shape.

The reason why the left and right recesses 57 and 58 are formed in the front mounting portion 53 will be described in detail later.

As shown in fig. 1, the vehicle underbody skeleton frame 12 is formed in an octagonal ring shape, and the ring-shaped skeleton portion 36 of the battery mounting frame 13 is formed in an octagonal ring shape. This can improve the strength and rigidity of the single body of the underbody skeleton frame 12 and the battery mounting frame 13.

Further, by forming the battery mounting frame 13 in an annular shape, the outer periphery of the battery 34 can be surrounded in all directions by the battery mounting frame 13. This allows the battery 34 (see fig. 4) to be sufficiently protected from external impact by the battery mounting frame 13.

Further, an annular frame portion 36 of the battery mounting frame 13 is fixed to the underbody frame 12. Thus, the vehicle underbody frame 12 and the battery mounting frame 13 are formed to have substantially the same contour. As a result, the functions (e.g., strength and rigidity) of the underbody frame 12 can be enhanced by the battery mounting frame 13, and therefore, the vehicle body structure 10 can be reduced in weight.

Further, by fixing the annular skeleton portion 36 to the vehicle underbody skeleton frame 12, the impact load due to the collision can be received by the vehicle underbody skeleton frame 12 and the annular skeleton portion 36 from the vehicle body front-rear direction, the vehicle width direction on the left and right, the vehicle front oblique direction, and the vehicle rear oblique direction. This protects the battery 34 against an impact load input from the vehicle body in all directions.

As shown in fig. 2 and 7, the rear end portion 14a of the left front side frame 14 is connected to the front end portion 22b of the left cantilever beam 22 in the vehicle underbody frame 12. Further, the rear end portion 14a of the right front side frame 14 is connected to the front end portion 22b of the right outrigger 22 in the vehicle underbody frame 12.

The front impact beam 16 is bridged to the front end portions 14b of the left and right front side frames 14 via extensions 19. The left and right front side frames 14 are provided at a distance from each other on the left and right outer sides of the power unit chamber 61 in the vehicle width direction of the vehicle body structure 10, and extend in the vehicle body front-rear direction. The power unit chamber 61 is a space for accommodating a power unit serving as a power source for driving, for example. The left and right front side frames 14 are high-rigidity members having a rectangular closed cross section, for example, and forming a vehicle body frame.

At the time of a front collision of the vehicle, the impact load is input to the front end portion 14b of the left and right front side frames 14 via the front impact beam 16 and the extension portion 19. The left and right front side frames 14 are buckled and deformed toward the rear of the vehicle body by an impact load input to the front end portions 14b, for example, thereby absorbing impact energy generated by a frontal collision while securing a collision deformation amount (energy absorption stroke).

A subframe 15 is provided below the left and right front side frames 14 and in front of the battery mounting frame 13 in the vehicle body.

As shown in fig. 2 and 8, the subframe 15 includes left and right side members 63, a front cross member 64, a rear cross member (cross member) 65, and left and right receiving members (receiving members) 66.

The left side member 63 is disposed below the left front side frame 14 and extends in the vehicle body longitudinal direction. The left side member 63 includes a first beam portion 71, a second beam portion 72, and a third beam portion (front portion of the subframe) 73.

The first beam portion 71 linearly extends in the vehicle body front-rear direction. The rear end 72a of the second beam portion 72 is connected to the front end 71a of the first beam portion 71. The second beam section 72 extends in a curved shape toward the front of the vehicle body so as to extend leftward in the vehicle width direction from the front end portion 71a of the first beam section 71. The third beam portion 73 is connected to the front end portion 72b of the second beam portion 72 toward the front of the vehicle body. The first beam portion 71, the second beam portion 72, and the third beam portion 73 are members having high rigidity, for example, formed in a rectangular shape with a closed cross section.

The third beam portion 73 forms a front portion of the left beam 63 and has a larger cross-sectional shape than a rear portion (i.e., the first beam portion 71 and the second beam portion 72) of the third beam portion 73.

The right side member 63 is formed bilaterally symmetrically with respect to the left side member 63. Hereinafter, the constituent members of the right side member 63 are denoted by the same reference numerals as those of the left side member 63, and detailed description of the right side member 63 is omitted.

The left side member 63 and the right side member 63 are disposed at a distance in the vehicle width direction and extend in the vehicle body front-rear direction. The front cross member 64 is bridged over the front end portion 71a of the first beam portion 71 of the left side member 63 and the front end portion 71a of the first beam portion 71 of the right side member 63 in the vehicle width direction.

The rear cross member 65 is erected along the front cross member 64 in the vehicle width direction at a portion 71b of the first beam portion 71 of the left side member 63 closer to the center rear end portion and at a portion 71b of the first beam portion 71 of the right side member 63 closer to the center rear end portion. A rear support portion 93 (see fig. 9) of the lower arm 18, which will be described later, is provided at a portion 71b closer to the center rear end portion. In other words, the rear cross bar 65 is bridged over the portion 71b of the left and right side members 63 where the rear support portion 93 of the lower arm 18 is provided.

The third beam portion 73 of the left side member 63 is disposed on the vehicle width direction outer left side of the first beam portion 71 via the second beam portion 72. In the third beam portion 73 of the left side member 63, the left receiving member 66 extends outward in the vehicle width direction from the front end portion 73 a.

The third beam portion 73 of the right side member 63 is disposed on the vehicle width direction right outer side of the first beam portion 71 via the second beam portion 72. In the third beam portion 73 of the right side member 63, the right receiving member 66 extends from the front end portion 73a to the right outer side in the vehicle width direction.

As shown in fig. 2 and 7, the left receiving member 66 of the left side member 63 is disposed at the left end portion 16a of the front impact beam 16 so as to overlap in the vertical direction (in a plan view).

The right receiving member 66 of the right side member 63 is disposed at the right end portion 16b of the front impact beam 16 so as to overlap in the vertical direction (in a plan view).

As a result, the impact load generated by, for example, a narrow offset frontal collision (narrow offset collision) of the vehicle can be received by the left and right receiving members 66. Thus, the vehicle body structure 10 can absorb impact energy due to a plane collision (full-circle front collision) of the vehicle, and can also absorb impact energy due to a narrow offset front collision of the vehicle.

As shown in fig. 7 and 9, the left side member 63 includes a front attachment portion 75, a center attachment portion 76, and a rear attachment portion 77.

The front attachment portion 75 projects leftward and outward in the vehicle width direction from the front end portion 71a of the first beam portion 71 of the left side member 63. The front attachment portion 75 is fastened and coupled to the front lower portion 14c of the left front side frame 14 by a fastening bolt 82 via a front support bracket 81 so as to allow separation in the vehicle body front-rear direction, for example. Specifically, for example, a front slit extending in the vehicle body longitudinal direction is formed in the lower portion of the front support bracket 81, and the front attachment portion 75 is attached to the lower portion of the front support bracket 81 by screwing in a state where the fastening bolt 82 is inserted into the front slit.

Thus, when an impact load is input to the left front side frame 14 due to a front collision, the front slit is disengaged from the fastening bolt 82, and the front support bracket 81 can be separated from the front mounting portion 75 in the vehicle body front-rear direction. This can avoid a situation in which the front attachment portion 75 (i.e., the left side member 63) obstructs the movement of the front lower portion 14c of the left front side frame 14 toward the rear of the vehicle body.

The center attachment portion 76 extends upward from the vehicle body front side of a portion 71b of the first beam portion 71 that is closer to the center rear end portion, and projects outward to the left in the vehicle width direction. The center attachment portion 76 is fastened and coupled to the center lower portion 14d of the left front side frame 14 by a fastening bolt 83 so as to allow separation in the vehicle width direction, for example. Specifically, for example, a center slit 84 extending in the vehicle width direction is formed in the upper end portion 76a of the center mounting portion 76, and a fastening bolt 83 is inserted into the center slit 84 to screw the center mounting portion 76 to the center lower portion 14 d. The center mounting portion 76 is mounted to the center lower portion 14d of the left front side frame 14 via a fastening bolt 83.

Thus, when an impact load is input to the left front side frame 14 due to a front collision, the center slit 84 is disengaged from the fastening bolt 83, and the center lower portion 14d of the front side frame 14 can be separated to the left outside in the vehicle width direction with respect to the center mounting portion 76.

This can avoid a situation in which the center mounting portion 76 (i.e., the left side member 63) obstructs the movement of the center lower portion 14d of the left front side frame 14 to the left outer side in the vehicle width direction.

In this way, the front attachment portion 75 of the left side member 63 is fastened and coupled to the front lower portion 14c of the left front side frame 14 so as to allow separation in the vehicle body longitudinal direction. The center mounting portion 76 of the left side member 63 is fastened and coupled to the center lower portion 14d of the left front side frame 14 so as to allow separation in the vehicle width direction.

Here, when an impact load due to a front collision is input to the front end portion of the left front side frame 14, the left front side frame 14 is buckled and deformed such that, for example, the front portion moves rearward in the vehicle body and the center portion moves in the vehicle width direction. This allows the front mounting portion 75 and the center mounting portion 76 to be separated from the left front side frame 14 when the left front side frame 14 is buckled and deformed toward the rear of the vehicle body by an impact load generated by a front collision.

This makes it possible to avoid a situation in which the sub-frame 15 obstructs deformation of the left front side frame 14, for example, in a state in which a member such as the steering mechanism 17 having high rigidity is disposed on the vehicle body front side of the sub-frame 15. Therefore, the collision deformation amount of the left front side frame 14 can be sufficiently ensured.

Next, the reason why the left and right concave portions 57 and 58 are formed in the front attachment portion 53 will be described in detail with reference to fig. 9 and 10.

As shown in fig. 9 and 10, the rear mounting portion 77 is formed by the rear end portion of the first beam portion 71 of the left side member 63, and is disposed in the left recess 57 of the left mounting end portion 53a of the front mounting portion 53. The rear mounting portion 77 is fastened and coupled to the left end portion 23a of the front cross member 23 by a fastening and coupling bolt 86 in a state of being disposed in the left recess 57.

Here, the stopper 45 of the battery mounting frame 13 faces the rear mounting portion 77 of the left side member 63 via the bottom portion 57a of the left recess 57. As a result, the rear mounting portion 77 of the left side member 63 can be brought close to the battery mounting frame 13 (specifically, the stopper portion 45), and the distance L1 between the rear mounting portion 77 and the stopper portion 45 can be reduced (see also fig. 11).

Thus, by moving the rear mounting portion 77 of the left side member 63 rearward of the vehicle body due to the impact load generated by the front collision, the rear mounting portion 77 can be brought into contact with the stopper portion 45 quickly, and the stopper portion 45 can receive the impact load well.

As shown in fig. 11, the front cross member 23 is formed into a hat-shaped cross section by the front wall 23c, the rear wall 23d, the bottom 23e, the front projecting piece 23f and the rear projecting piece 23G, and the center of gravity position G1 is located at substantially the center of the hat-shaped cross section. The center of gravity G1 of the front cross member 23 is located in front of the vehicle body to which the coupling bolt 86 is fastened. The rear mounting portion 77 of the left side member 63 is mounted to the left end portion 23a of the front cross member 23 by fastening the fastening bolt 86. That is, the rear mounting portion 77 is fixed to the vehicle body rear side with the fastening bolt 86 at the center of gravity position G1 of the front cross member 23.

Here, the impact load generated by the front collision is input to the front cross member 23 of the under frame 12 via the rear mounting portion 77 and the fastening bolt 86. That is, an impact load to reverse the front cross member 23 toward the battery mounting frame 13 about the center of gravity position G1 is input to the front cross member 23 via the fastening bolt 86.

Therefore, the rear mounting portion 77 of the left side member 63 is fixed to the vehicle body rear side with respect to the center of gravity position G1 of the front cross member 23. This enables the rear mounting portion 77 of the left side member 63 to quickly and reliably come into contact with the stopper portion 45 (i.e., the front surface of the battery mounting frame 13), and thus the impact load can be quickly transmitted to the battery mounting frame 13.

Returning to fig. 2 and 9, the right side member 63 is also fastened and coupled to the right front side frame 14 and the right end portion 23b of the front cross member 23 by the fastening and coupling bolt 82, the fastening and coupling bolt 83, and the fastening and coupling bolt 86, in the same manner as the left side member 63.

That is, the front attachment portion 75 is attached to the front lower portions 14c of the left and right front side frames 14 via the front support brackets 81 and the fastening bolts 82 so as to be separable in the vehicle body front-rear direction. The center mounting portion 76 is mounted to the center lower portions 14d of the left and right front side frames 14 via fastening bolts 83 so as to be separable in the vehicle width direction.

This allows the sub-frame 15 to be separated from the left and right front side frames 14 when an impact load is input to the left and right front side frames 14. This allows the left and right front side frames 14 to be buckled and deformed rearward of the vehicle body, thereby absorbing impact energy.

As shown in fig. 3 and 12, a steering mechanism 17 is disposed on the vehicle body front side of the subframe 15. Specifically, the steering mechanism 17 is provided on the vehicle body front side of the first beam portion 71 of the left side member 63 and the first beam portion 71 (see fig. 2) of the right side member 63. The steering mechanism 17 houses a rack and pinion, for example, inside a steering gear box 17 a.

The rack is engaged with the pinion, extends in the vehicle width direction, and is connected to left and right tie rods 17 b. Left and right tie rods 17b (only the left tie rod 17b is shown) extend outward in the vehicle width direction from the steering gear box 17 a. The steering mechanism 17 is a highly rigid member.

A lower arm 18 is disposed behind the steering mechanism 17, and the lower arm 18 is fixed to the first beam portion 71 of the left side member 63 and the first beam portion 71 of the right side member 63 (see fig. 2). In a state where the lower arm 18 is fixed to the first beam portion 71 of the left side member 63, the suspension is supported by the lower arm 18 via the knuckle 89. The front wheels are supported by the suspension via a knuckle 89.

The lower arm 18 includes an arm body 91, a front support 92, and a rear support 93.

The arm main body 91 is disposed between the front support portion 92 and the rear support portion 93, and is connected to the front support portion 92 and the rear support portion 93. The front support 92 and the rear support 93 are arranged in this order toward the rear of the vehicle body.

Specifically, the front support section 92 is fixed to a portion 71c of the first beam section 71 that is located near the vehicle body rear side of the steering mechanism 17. Rear support portion 93 is disposed behind front support portion 92 in the vehicle body, and includes a beam support portion 97 and a frame support portion 98.

As shown in fig. 3 and 9, the beam support portion 97 is coupled to a portion 71b of the first beam portion 71 that is located at a center rear end portion of the front support portion 92 in the vehicle rear direction by a fastening bolt 101. The frame support portion 98 is coupled to a coupling bracket (bracket) 103 of the left front side frame 14 by a fastening coupling bolt 104. That is, the rear support portion 93 is bridged between the portion 71b of the first beam portion 71 closer to the center rear end portion and the connecting bracket 103 of the left front side frame 14.

Here, the frame support portion 98 includes a downward movement allowing portion 105 that allows downward movement with respect to the coupling bracket 103 of the left front side frame 14. Specifically, for example, a slit (groove) is formed as the downward movement allowing section 105. The fastening bolt 104 is inserted into the downward movement allowing portion (i.e., the slit) 105 to fasten and couple the frame support portion 98 to the coupling bracket 103.

Thus, when the left side member 63 is deformed by an impact load input to the front end portion 15a of the sub-frame 15 (the front end portion of the left side member 63), the downward movement allowing portion (slit) 105 is disengaged from the fastening bolt 104, and the frame support portion 98 is allowed to move downward. This allows the lower arm 18 to smoothly move downward together with the left side member 63 and to be positioned below the battery 34.

As shown in fig. 9 and 10, the left side member 63 includes a deformation facilitating portion 110 provided between the steering mechanism 17 and the rear mounting portion 77. The easy-to-deform portion 110 is formed of, for example, three bent portions, i.e., a first bent portion 112, a second bent portion 113, and a third bent portion 114.

In the embodiment, the example in which the easy-to-deform portion 110 is constituted by the first to third bent portions 112 to 114 has been described, but the number of the bent portions is not limited thereto. Three or more may be provided.

The first bent portion 112 is provided, for example, at a lower surface portion 71d of the first beam portion 71 of the left side beam 63, which is located in the vicinity of the vehicle body front side of the rear crossbar 65. The first bent portion 112 is formed, for example, in an upward concave shape and is formed of a groove portion extending in the vehicle width direction. The third bent portion 114 is provided, for example, at the lower surface portion 71e of the first beam portion 71 near the vehicle body front side of the rear mounting portion 77. The third bent portion 114 is formed in an upward concave shape, for example, and is formed by a stepped portion extending in the vehicle width direction.

The second bend 113 is formed, for example, on an upper surface portion 71f of the first beam portion 71, which is located at the center between the first bend 112 and the third bend 114. The second bent portion 113 is formed, for example, in a downward concave shape and is formed of a groove portion (groove) extending in the vehicle width direction. Hereinafter, the second bent portion 113 will be described as the "portion to be displaced 113".

As shown in fig. 12, the displacement scheduled portion 113 is provided between the steering mechanism 17 and the rear mounting portion 77 (see fig. 10), and is provided adjacent to the rear support portion 93 of the lower arm 18 behind the vehicle body of the rear support portion 93. In other words, the rear support portion 93 of the lower arm 18 is fixed to the vehicle body front side of the to-be-displaced portion 113. The displacement scheduled portion 113 is formed in a downward concave shape by the groove portion. Thus, when an impact load generated by a front collision is input to the front end portion 15a of the subframe 15 (the front end portion of the left side member 63 (see fig. 3)), the displacement scheduled portion 113 can be deformed downward by the input impact load.

As shown in fig. 11, the third bent portion 114 is located at the rearmost end of the first to third bent portions 112 to 114 (the first bent portion 112 is shown in fig. 10) arranged in this order toward the rear of the vehicle body.

The rear mounting portion 77 is provided adjacent to the third bent portion 114 at the rear of the rearmost third bent portion 114 in the vehicle body. The reinforcing plate 116 is overlapped from below on the mounting surface 77a of the rear mounting portion 77.

In this state, the reinforcing plate 116 is mounted by the fastening bolts 86 in a state of being superimposed on the mounting surface 77a of the rear mounting portion 77. The reinforcing plate 116 is formed of, for example, a flat steel plate. The mounting surface 77a of the rear mounting portion 77 is reinforced by the reinforcing plate 116. Further, a third bent portion 114 is formed adjacent to the reinforcing plate 116 on the vehicle body front side of the reinforcing plate 116.

As a result, when an impact load generated by a front collision is input to the front end portion 15a of the subframe 15 (the front end portion of the left side member 63) (see fig. 3), stress can be concentrated in the third bent portion 114. This makes it possible to quickly bend the first to third bent portions 112 to 114 of the left side member 63 (specifically, the first beam portion 71) by an impact load generated by a front collision, thereby facilitating deformation of the subframe 15.

Next, an example in which the impact load generated by the front collision is absorbed by the vehicle body structure 10 will be described in detail with reference to fig. 9, 12, 13A, 13B, and 14.

As shown in fig. 13A, the left side member 63 of the subframe 15 is provided with a deformation facilitating portion 110. The rear mounting portion 77 of the left side member 63 is disposed in the left recess 57 (see also fig. 3). Further, the stopper 45 of the battery mounting frame 13 faces the rear mounting portion 77 of the left side member 63 via the bottom portion 57a (see also fig. 6) of the left recess 57.

In this state, an impact load F1 generated by a front collision is input to the front end portion 14b of the left front side frame 14. Further, the impact load F2 generated by the front collision is input to the left side member 63 (specifically, the first beam member 71) of the subframe 15.

As shown in fig. 13B, the impact load F1 is input to the front end portion 14B of the left front side frame 14, and buckling deformation in the vehicle body rear direction by the left front side frame 14 starts.

Further, when the impact load F2 is input to the first beam portion 71 of the left side member 63, the rear mounting portion 77 of the left side member 63 abuts against the stopper portion 45. By bringing the rear mounting portion 77 into contact with the stopper portion 45, the easy-to-deform portion 110 (i.e., the first to third bent portions 112 to 114) of the left side member 63 is bent, and the left side member 63 is deformed.

The left front side frame 14 is deformed so as to be buckled more rapidly, for example, such that the front portion moves rearward of the vehicle body and the center portion moves in the vehicle width direction. As the front portion of the left front side frame 14 moves rearward of the vehicle body, the front mounting portion 75 separates from the front support bracket 81 of the left front side frame 14. Further, the center portion of the left front side frame 14 moves in the vehicle width direction, and the center attachment portion 76 is separated from the left front side frame 14.

Thus, even if a member such as the steering mechanism 17 having high rigidity is disposed on the vehicle body front side of the subframe 15, it is possible to avoid a situation in which the deformation of the left front side frame 14 is hindered by the subframe 15. This ensures the collision deformation amount of the left front side frame 14, and absorbs the impact energy generated by the front collision.

Here, the reason why the front skeleton portion 45 of the annular skeleton portion 36 is also used as the stopper portion 45 will be described in detail.

That is, when the impact load F2 is input to the first beam member 71 of the left side member 63, the stopper 45 can support the rear mounting portion 77 of the left side member 63 that moves rearward in the vehicle body. This makes it possible to disperse the impact load F2 generated by the front collision to the battery mounting frame 13 and the underbody frame 12. This can reduce the cross-sectional shape and the thickness dimension of the underbody skeleton frame 12, and can reduce the weight of the vehicle body structure 10.

The second bent portion 113 at the center of the three bent portions 112 to 114 is set as the portion to be displaced 113. The portion to be displaced 113 is formed so as to be buckled downward by an impact load F2 generated by a front collision. By setting the second bent portion 113 at the center as the portion to be displaced 113, the portion to be displaced 113 can be moved downward greatly. By buckling the displacement scheduled portion 113 downward in this way, the impact deformation amount of the left front side frame 14 can be ensured to absorb the impact energy.

Further, a lower arm 18 (see fig. 12) is provided in front of the displacement portion 113 in the vehicle body. The displacement scheduled portion 113 is formed adjacent to the rear support portion 93 (see fig. 12) of the lower arm 18. Accordingly, the portion to be displaced 113 of the left side member 63 is buckled downward, whereby the downward movement amount of the lower arm 18 can be secured in the same manner as the portion to be displaced 113.

This allows the lower arm 18 to be appropriately moved rearward of the vehicle body and downward of the battery 34 to avoid interference with the battery 34. Therefore, interference between the lower arm 18 and the battery 34 can be avoided without using additional members such as a guide roller and a rear end portion of the subframe, which are necessary in the conventional vehicle body structure.

As shown in fig. 9 and 12, in addition to fig. 13A and 13B, a rear cross bar 65 is erected at a portion 71B of the left and right side members 63 closer to the central rear end portion of the rear support portion 93 provided with the lower arm 18. Here, the displacement scheduled portion 113 is formed adjacent to the rear support portion 93 of the lower arm 18. Thus, even when the impact load F2 input by a front collision varies in the vehicle width direction, the load transmitted to the left and right displacement portions 113 can be equalized by the rear cross member 65. Thus, even when the impact load F2 is unevenly input in the vehicle width direction, the left and right lower arms 18 can be uniformly lowered.

Further, a deformation facilitating portion 110 is provided between the steering mechanism 17 and the rear mounting portion 77 of the left side member 63. Thus, the impact load F2 caused by the front collision deforms the left side member 63 at the deformation facilitating portion 110, and moves the steering mechanism 17 rearward of the vehicle body.

In this case, the subframe 15 can be prevented from being sandwiched between the subframe 15 and the dash lower panel 29, and the subframe 15 can be sufficiently deformed (crushed).

This enables the left front side frame 14 to be sufficiently buckled (squashed), and a sufficient amount of collision deformation can be obtained without detaching the rear mounting portion 77 of the left side member 63 from the vehicle body.

As shown in FIG. 14, the easy-to-deform portion 110 is formed by three bent portions, i.e., first to third bent portions 112 to 114. As a result, the left side member 63 (specifically, the first beam member 71) of the subframe 15 can be buckled and deformed in a corrugated shape in a side view at the easy deformation portion 110 by the impact load F2 generated by the front collision. This enables a large amount of impact energy to be absorbed by the subframe 15.

Further, by causing the sub-frame 15 to be buckled and deformed in a corrugated shape, the pressing force F3 for moving the rear mounting portion 77 of the left side member 63 rearward of the vehicle body can be made larger than the rotational force F4 acting on the rear mounting portion 77. By increasing the pressing force F3 that moves the rear mounting portion 77 toward the rear of the vehicle body, the shearing force acting on the fastening bolt 86 can be increased. This can break the fastening bolt 86 by a shearing force and move the rear mounting portion 77 to the rear of the vehicle body.

This ensures a large contact surface between the rear mounting portion 77 and the stopper portion 45. Therefore, the impact load F2 can be transmitted favorably from the rear mounting portion 77 to the stopper portion 45, and the impact load F2 can be received favorably by the stopper portion 45 (i.e., the battery mounting frame 13).

Next, the vehicle body structures according to the second to fourth embodiments will be described with reference to fig. 15 to 18. In the second to fourth embodiments, the same or similar constituent members as those of the vehicle body structure 10 of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(second embodiment)

As shown in fig. 15, the vehicle body structure 130 is obtained by replacing the battery mounting frame 13 of the first embodiment with a battery mounting frame 132, and the other structure is the same as that of the first embodiment.

The battery mounting frame 132 is formed in a ring shape along the underbody frame 12 by a highly rigid vehicle body frame member. Specifically, the corners 132a to 132d of the battery mounting frame 132 are formed in a curved shape (arc shape), and the other configurations are the same as those of the battery mounting frame 13 of the first embodiment. The battery mounting frame 132 is fixed to the underbody frame 12 by a plurality of fastening bolts 31.

According to the vehicle body structure 130 of the second embodiment, the strength and rigidity of the single body of the underbody skeleton frame 12 and the battery mounting frame 132 can be improved by forming the battery mounting frame 132 in a ring shape, as in the vehicle body structure 10 of the first embodiment. Further, a battery mounting frame 132 is fixed to the underbody frame 12. As a result, the battery mounting frame 132 can compensate for the functions (e.g., strength and rigidity) of the underbody frame 12, and therefore the vehicle body structure 130 can be reduced in weight.

Further, by forming the battery mounting frame 132 in a ring shape, the outer periphery of the battery 34 (see fig. 4) can be surrounded in all directions by the battery mounting frame 132. This makes it possible to sufficiently protect the battery 34 from external impact by the battery mounting frame 132.

In the second embodiment, the example in which the corners 132a to 132d of the battery mounting frame 132 are formed in a curved shape has been described, but the entire battery mounting frame 132 may be formed in a curved shape (arc shape).

(third embodiment)

As shown in fig. 16, a vehicle body structure 140 is obtained by replacing the annular frame portion 36 of the battery mounting frame 13 of the first embodiment with an annular frame portion 142, and the other structure is the same as that of the first embodiment.

The annular frame portion 142 includes a frame upper wall 41, a frame lower wall 42, an outer vertical wall 43, and a plurality of reinforcing ribs 143. The outer peripheral portion 38 of the annular frame portion 142 is formed in a U-shaped cross section by the frame upper wall 41, the frame lower wall 42, and the outer vertical wall 43. A plurality of reinforcing ribs 143 are provided at intervals inside the outer peripheral portion 38. Thereby, the outer peripheral portion 38 is reinforced by the plurality of reinforcing ribs 143. Thus, the annular frame portion 142 is formed as a highly rigid frame member by providing the plurality of reinforcing ribs 143 inside the outer peripheral portion 38.

(fourth embodiment)

As shown in fig. 17, a vehicle body structure 150 is obtained by replacing the battery mounting frame 13 of the first embodiment with a battery mounting frame 152, and the other structure is the same as that of the first embodiment.

Here, the battery mounting frame 13 of the first embodiment includes left and right recesses 57 and 58 (see fig. 6) in the vehicle body mounting portion 37. In contrast, the battery mounting frame 152 of the second embodiment includes a vehicle body mounting portion 153 instead of the vehicle body mounting portion 37 of the first embodiment.

Thus, the battery mounting frame 152 forms a space 154 between the vehicle body mounting portion 153 and the under frame 12.

As shown in fig. 18, a space 154 (see fig. 17) is formed between the vehicle body mounting portion 153 of the battery mounting frame 152 and the underbody skeleton frame 12. This allows the left and right rear mounting portions 77 to enter the space 154 when the left and right rear mounting portions 77 of the subframe 15 move rearward of the vehicle body due to the impact load F2 generated by the front collision. As a result, the left and right rear mounting portions 77 can be brought into contact with the front frame portion (i.e., stopper portion) 45 of the battery mounting frame 152, and the impact load F2 can be transmitted.

Further, the left and right rear mounting portions 77 of the subframe 15 can be moved along the upper side of the vehicle body mounting portion 153 of the battery mounting frame 152 by inserting the left and right rear mounting portions 77 into the space 154. This prevents the fastening bolts 86 (see fig. 17) that attach the left and right rear attachment portions 77 of the subframe 15 to the underbody frame 12 from falling off from the vehicle body attachment portions 153.

In addition, the components in the above-described embodiments may be replaced with known components as appropriate within a range not departing from the gist of the present invention, and the above-described modifications may be combined as appropriate.

Description of the symbols

10. 130, 140, 150 vehicle body structure

12 vehicle body bottom framework frame

13. 132, 152 storage battery mounting frame

15 subframe

17 steering mechanism

21 left and right lower side beam (each side of the vehicle body bottom framework)

22 left and right cantilever beam (each side of the chassis frame of the vehicle body)

23 front beam (each side of the vehicle body bottom framework)

24a left and right rear frame front parts (sides of vehicle body bottom frame)

25 rear beam (each side of the vehicle body bottom framework)

36. 142 annular skeleton portion

37. 153 vehicle body mounting part

38 outer peripheral portion

41 framework upper wall (Upper wall)

42 skeleton lower wall (lower wall)

43 outer plumb wall (plumb wall)

45 stopper

57. About 58 concave part

66 left and right bearing members (bearing members)

71. 72 rear part of the third beam section (first and second beam sections)

73 third Beam section (front section of subframe)

77 left and right rear mounting parts (rear mounting part)

77a mounting surface

110 easily deformable part

112 to 114 first to third bending parts (bending parts)

116 reinforcing plate

143 reinforcing rib

154 space

G1 center of gravity position

The claims (modification according to treaty clause 19)

(modified) a vehicle body structure, comprising:

an annular underbody skeleton frame formed along an outer periphery of the floor panel;

an annular battery mounting frame fixed to the underbody skeleton frame; and

a sub-frame provided in front of the battery mounting frame,

the subframe includes a deformation facilitating portion provided in front of a vehicle body fixed to a rear mounting portion of the underbody skeleton frame,

the battery mounting frame includes a stopper portion facing the rear mounting portion of the sub frame,

the battery mounting frame is provided with:

a vehicle body mounting portion provided on an outer side and mounted to the vehicle body bottom skeleton frame; and

a concave part which is arranged on the vehicle body installation part and is formed in a concave shape towards the inner side,

the rear mounting part of the sub-frame is disposed in the recess

2. The vehicle body structure according to claim 1,

the sub-frame is provided with a steering mechanism on the front side of the vehicle body, and the easy-to-deform portion is provided between the steering mechanism and the rear mounting portion of the sub-frame.

3. The vehicle body structure according to claim 1 or 2,

the easily deformable portion of the subframe is formed of at least three bent portions.

4. The vehicle body structure according to claim 3,

the rear mounting portion of the subframe is provided with a reinforcing plate that overlaps a mounting surface on the vehicle body rear side of the rearmost bent portion of the bent portions.

(deletion)

(modified) the vehicle body structure according to any one of claims 1 to 4,

the rear mounting portion of the subframe is fixed to a position behind the vehicle body with respect to a center of gravity of the underbody skeleton frame.

(modified) the vehicle body structure according to claim 1,

the vehicle underbody skeleton frame is formed in an octagonal ring shape in a plan view,

the battery mounting frame includes an annular frame portion having an octagonal shape in a plan view, and is fixed to each side of the underbody frame.

8. The vehicle body structure according to claim 7,

the annular frame portion of the battery mounting frame has an outer peripheral portion formed by at least an upper wall, a lower wall, and a vertical wall connecting the upper wall and the lower wall,

the vehicle body attachment portion is integrally provided on the vertical wall.

(modified) the vehicle body structure according to claim 1 or 8,

a space is formed between the vehicle body mounting portion of the battery mounting frame and the vehicle body bottom skeleton frame.

(modified) the vehicle body structure according to any one of claims 1 to 4 and 6 to 9,

the subframe is formed such that a front portion has a larger cross section than a rear portion, and includes a receiving member that protrudes outward in the vehicle width direction from the front portion to receive an impact load generated by a narrow offset collision.

Claims (10)

1. A vehicle body structure is characterized by comprising:

an annular underbody skeleton frame formed along an outer periphery of the floor panel;

an annular battery mounting frame fixed to the underbody skeleton frame; and

a sub-frame provided in front of the battery mounting frame,

the subframe includes a deformation facilitating portion provided in front of a vehicle body fixed to a rear mounting portion of the underbody skeleton frame,

the battery mounting frame includes a stopper portion facing the rear mounting portion of the subframe.

2. The vehicle body structure according to claim 1,

the sub-frame is provided with a steering mechanism on the front side of the vehicle body, and the easy-to-deform portion is provided between the steering mechanism and the rear mounting portion of the sub-frame.

3. The vehicle body structure according to claim 1 or 2,

the easily deformable portion of the subframe is formed of at least three bent portions.

4. The vehicle body structure according to claim 3,

the rear mounting portion of the subframe is provided with a reinforcing plate that overlaps a mounting surface on the vehicle body rear side of the rearmost bent portion of the bent portions.

5. The vehicle body structure according to any one of claims 1 to 4,

the battery mounting frame is provided with:

a vehicle body mounting portion provided on an outer side and mounted to the vehicle body bottom skeleton frame; and

a concave part which is arranged on the vehicle body installation part and is formed in a concave shape towards the inner side,

the rear mounting portion of the subframe is disposed in the recess.

6. The vehicle body structure according to any one of claims 1 to 5,

the rear mounting portion of the subframe is fixed to a position behind the vehicle body with respect to a center of gravity of the underbody skeleton frame.

7. The vehicle body structure according to claim 5,

the vehicle underbody skeleton frame is formed in an octagonal ring shape in a plan view,

the battery mounting frame includes an annular frame portion having an octagonal shape in a plan view, and is fixed to each side of the underbody frame.

8. The vehicle body structure according to claim 7,

the annular frame portion of the battery mounting frame has an outer peripheral portion formed by at least an upper wall, a lower wall, and a vertical wall connecting the upper wall and the lower wall,

the vehicle body attachment portion is integrally provided on the vertical wall.

9. The vehicle body structure according to claim 5 or 8,

a space is formed between the vehicle body mounting portion of the battery mounting frame and the vehicle body bottom skeleton frame.

10. The vehicle body structure according to any one of claims 1 to 9,

the subframe is formed such that a front portion has a larger cross section than a rear portion, and includes a receiving member that protrudes outward in the vehicle width direction from the front portion to receive an impact load generated by a narrow offset collision.

Images