Body structure

Abstract

To obtain a vehicle body structure capable of controlling the breaking load at the time of a vehicle collision by an impact absorbing part. [Solution] The impact absorbing section 14 is configured to include a plurality of areas (low load area 28, high load area 30, and destruction suppression area 32) corresponding to the stroke in response to the input of an impact load F, and the plurality of areas (low load area 28, high load area 30, and destruction suppression area 32) have different load resistance in response to the input of the impact load F. This enables the impact absorbing section 14 to control the load in response to the stroke in response to the input of the impact load F. In other words, the impact absorbing section 14 can control the destruction load (load resistance) in the event of a vehicle collision.

Description

[Technical Field]

[0001] The present invention relates to a vehicle body structure. [Background technology]

[0002] Patent Document 1 discloses a vehicle body structure in which left and right wheel houses and a cross member are integrally formed by casting. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2022 / 031991 publication Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, a vehicle body structure is required to absorb the impact force during a vehicle collision. Therefore, when an energy-absorbing casting is provided to absorb the impact force in the above-mentioned prior art, it is difficult to control the breaking load during a vehicle collision with the energy-absorbing casting (impact-absorbing portion) in various deformation modes.

[0005] SUMMARY OF THE INVENTION In consideration of the above, an object of the present invention is to provide a vehicle body structure capable of controlling the breaking load at the time of a vehicle collision by means of an impact absorbing portion. [Means for solving the problem]

[0006] The vehicle body structure according to the present invention as set forth in claim 1 is provided with an impact absorbing portion configured to include a plurality of areas with different load resistances corresponding to strokes with respect to input of an impact load.

[0007] In the vehicle body structure according to the present invention, the impact absorbing portion includes a plurality of areas corresponding to the stroke of the input impact load, and the plurality of areas have different load resistances to the input impact load. This makes it possible to control the load in accordance with the stroke of the input impact load. In other words, the present invention makes it possible to effectively absorb impact energy in accordance with the stroke of the input impact load, and as a result, it becomes possible to suppress the impact load from entering the vehicle interior.

[0008] The vehicle body structure of the present invention described in claim 2 is the vehicle body structure of the present invention described in claim 1, wherein the impact absorbing portion is configured to include a low load area, a high load area, and a destruction suppression area along the input direction of the impact load, and the load capacity increases in the order of the low load area, the high load area, and the destruction suppression area.

[0009] In the vehicle body structure according to the present invention described in claim 2, the impact absorbing section is configured to include a low load area, a high load area, and a destruction suppression area along the input direction of the impact load. In the impact absorbing section, the load resistance against the input of the impact load increases in the order of the low load area, the high load area, and the destruction suppression area.

[0010] Therefore, in the present invention, the impact energy can be absorbed in stages in the impact absorbing section, at least from the low load area to the high load area, before the impact load input from outside the vehicle is transmitted from the outside to the inside of the vehicle, thereby preventing a large impact value from being input to the occupants.

[0011] The vehicle body structure of the present invention described in claim 3 is the vehicle body structure of the present invention described in claim 2, wherein the cross-sectional height of the destruction suppression area along the vehicle vertical direction is greater than the cross-sectional heights of the low load area and the high load area.

[0012] In the vehicle body structure according to the present invention, the fracture prevention area has a cross-sectional height in the vehicle vertical direction that is greater than the cross-sectional heights of the low load area and the high load area, and has a higher section modulus than the low load area and the high load area. Therefore, in the present invention, the fracture prevention area has a larger cross-sectional moment of inertia and higher bending rigidity than the low load area and the high load area. Therefore, the fracture prevention area can suppress deformation more effectively than the low load area and the high load area.

[0013] The vehicle body structure of the present invention described in claim 4 is the vehicle body structure of the present invention described in claim 2, wherein the impact absorbing portion is provided along the longitudinal direction of the vehicle, and the rigidity of the ribs arranged in multiple rows along the longitudinal direction of the vehicle, spanning between the upper wall portion and the lower wall portion that constitute part of the low load area, increases from the front end to the rear end of the low load area.

[0014] In the vehicle body structure according to the present invention, the impact absorbing portion is provided along the longitudinal direction of the vehicle. A rib is bridged between the upper wall portion and the lower wall portion that constitute a part of the low load area, and a plurality of the ribs are arranged along the longitudinal direction of the vehicle. The ribs have a pitch that becomes shorter or a thickness that becomes thicker from the front end to the rear end of the low load area, for example, so that the rigidity of the ribs increases from the front end to the rear end of the low load area. As a result, the crushing load in the low load area gradually increases from the front end to the rear end of the low load area.

[0015] The vehicle body structure of the present invention described in claim 5 is the vehicle body structure of the present invention described in claim 2, in which the cross-sectional height in the vehicle vertical direction in the high load area gradually increases from the low load area to the destruction suppression area.

[0016] In the vehicle body structure according to the present invention, the cross-sectional height in the vehicle vertical direction in the high load area gradually increases from the low load area to the destruction suppression area, and the rigidity gradually increases from the low load area to the destruction suppression area. This makes it possible to gradually increase the amount of impact energy absorption in the high load area and prevent a large impact from being applied to the occupant. [Effects of the Invention]

[0017] As described above, the vehicle body structure according to the present invention can control the breaking load during a vehicle collision by using the impact absorbing member. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a perspective view of a vehicle body structure according to an embodiment of the present invention, seen from diagonally forward left and above the vehicle. [Figure 2] 1 is a side view showing a vehicle body structure according to an embodiment of the present invention; [Figure 3] 3 is an enlarged side view of a main part of FIG. 2 showing an impact absorbing portion provided in the vehicle body structure according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, a vehicle body structure according to an embodiment of the present invention will be described with reference to the drawings. Note that the arrow FR shown as appropriate in each drawing indicates the front side in the vehicle longitudinal direction, and the arrow UP indicates the upper side in the vehicle vertical direction. The arrow LH indicates the left side in the vehicle width direction, and in this embodiment indicates the outer side in the vehicle width direction. Hereinafter, when the directions of front-rear, up-down, and left-right are simply used in the description, they refer to front-rear in the vehicle longitudinal direction, up-down in the vehicle vertical direction, and left-right in the vehicle horizontal direction (vehicle width direction), unless otherwise specified.

[0020] <Body structure configuration> First, the configuration of the vehicle body structure according to this embodiment will be described.

[0021] FIG. 1 shows an overall view of a vehicle 10, illustrating the framework of the vehicle. For example, the vehicle 10 may be an electric vehicle or a fuel cell vehicle that runs on power generated by a power unit, although this is not shown. As shown in FIG. 1, an impact absorbing section 14 to which a vehicle body structure 12 according to this embodiment is applied constitutes, for example, at least a part of a front side member 16. The front side member 16 is a framework member on the side of the vehicle 10, and in this embodiment, is formed by casting using an aluminum alloy, a magnesium alloy, or the like.

[0022] The front side members 16 are disposed on both the left and right sides of the front of the vehicle in the vehicle width direction, and extend in the vehicle longitudinal direction. The power unit is disposed between the left and right front side members 16. Crash boxes 18 capable of absorbing impact energy extend in the vehicle longitudinal direction on the front sides of the left and right front side members 16, and a front bumper 20 extends in the vehicle width direction at the front ends of the left and right crash boxes 18. Note that, although the front bumper 20 and the crash boxes 18 are described here as separate components, they may also be configured as an integrated unit.

[0023] Meanwhile, wheel houses 22 in which wheels (not shown) are arranged are provided on the outer sides of the left and right front side members 16 in the vehicle width direction, including the left and right front side members 16. The right wheel house 22 and the left wheel house 22 are connected by a cross member 24. For example, the left and right front side members 16, the left and right wheel houses 22, and the cross member 24 may be integrally formed by casting.

[0024] (Shock absorbing part) Here, the impact absorbing portion 14 provided in the vehicle body structure 12 according to this embodiment will be described.

[0025] In this embodiment, the impact absorbing portion 14 is provided on a front side member 16. The cross section of the front side member 16 when cut along the vehicle vertical direction and vehicle width direction forms a substantially U-shape with an opening on the outer side in the vehicle width direction.

[0026] 2, the shock absorbing section 14 is configured to include, for example, a destruction initiation area 26, a low load area (area) 28, a high load area (area) 30, and a destruction suppression area (area) 32 along the input direction of the impact load F. The low load area 28, the high load area 30, and the destruction suppression area 32 have increasing load resistance against the input of the impact load F in this order.

[0027] The destruction initiation area 26 is the portion where the crushing of the impact absorbing section 14 begins, and the destruction initiation area 26, the low load area 28, and the high load area 30 each have, for example, one substantially rectangular closed cross-sectional portion 34 whose longitudinal direction is the fore-and-aft direction of the vehicle when viewed from the side of the vehicle. The destruction initiation area 26 and the high load area 30 are formed with a shorter stroke than the low load area 28. Note that each area may be composed of a plurality of partitioned closed cross-sectional portions.

[0028] As shown in Figure 3, this closed cross-sectional portion 34 is composed of a rear wall portion 36 arranged on the inside in the vehicle width direction, a vertical wall portion 38 erected toward the outside in the vehicle width direction at the front end of the rear wall portion 36 in the vehicle fore-and-aft direction, and a vertical wall portion 40 erected toward the outside in the vehicle width direction at the rear end of the rear wall portion 36 in the vehicle fore-and-aft direction.

[0029] The upper ends of the rear wall portion 36, the vertical wall portion 38, and the vertical wall portion 40 are connected by a horizontal wall portion (upper wall portion) 42, and the lower ends of the rear wall portion 36, the vertical wall portion 38, and the vertical wall portion 40 are connected by a horizontal wall portion (lower wall portion) 44. In other words, the closed cross-sectional portion 34 is composed of the rear wall portion 36, the vertical wall portions 38, 40, and the horizontal wall portions 42, 44.

[0030] Furthermore, the rear wall portion 36, the vertical wall portion 38, and the vertical wall portion 40 are connected at approximately the center in the vertical direction by a horizontal wall portion 46, and the closed cross-sectional portion 34 is divided into two upper and lower stages, an upper stage portion 48 and a lower stage portion 50. In the following description, wall portions formed continuously across multiple areas will be described using the same reference numerals regardless of the area.

[0031] (Destruction start area) First, the configuration of the destruction start area 26 will be briefly described.

[0032] Within the upper and lower sections 48 and 50 of the destruction initiation area 26, vertical ribs 58 and 60 are respectively arranged between the lateral wall section 42 and the lateral wall section 46, and between the lateral wall section 46 and the lateral wall section 44 in the up-down direction. A plurality of the vertical ribs 58 and the vertical ribs 60 are arranged in the longitudinal direction of the vehicle, and the vertical ribs 58 and the vertical ribs 60 are arranged offset in the longitudinal direction of the vehicle. In other words, the vertical ribs 58 and the vertical ribs 60 are not continuous in the up-down direction. The thickness of the plurality of vertical ribs 58 and 60 may vary depending on the position in the longitudinal direction of the vehicle.

[0033] On the other hand, for example, a triangular notch 56 that protrudes upward is provided in the side wall 42 of the destruction initiation area 26, and the notch 56 is a weak part that is set to have lower rigidity than other parts. When an impact load F is input from outside the vehicle and the impact absorbing part 14 collapses, the impact value becomes large at the start of the collapse.

[0034] Therefore, by providing the notch 56 in the destruction initiation area 26, the notch 56 can be used as the starting point for the initiation of collapse of the impact absorbing part 14, thereby reducing the impact on the occupant at the start of the collapse. Also, it is possible to suppress the remaining crushed part at the front end where the impact absorbing part 14 starts to collapse, and to collapse the impact absorbing part 14 in order from the front end.

[0035] Note that the notch portion 56 need only be formed at the starting point of the collapse of the impact absorbing portion 14, and is not limited to being formed on the side wall portion 42. Therefore, the notch portion 56 may also be formed on the side of the side wall portion 44.

[0036] (low load area) Next, the low load area 28, the high load area 30, and the fracture suppression area 32 will be described in detail in this order.

[0037] In the upper and lower sections 48 and 50 of the low load area 28, similar to the destruction initiation area 26, vertical ribs 58 and 60 are respectively provided between the lateral wall section 42 and the lateral wall section 46, and between the lateral wall section 46 and the lateral wall section 44 in the up-down direction. A plurality of the vertical ribs 58 and 60 are arranged in the longitudinal direction of the vehicle, and the vertical ribs 58 and the vertical ribs 60 are arranged offset in the longitudinal direction of the vehicle and are not continuous in the up-down direction.

[0038] In the low load area 28, the pitch of the longitudinal ribs 58, 60 decreases toward the rear of the vehicle. The longitudinal ribs 58, 60 are formed as thick ribs 62, 64, for example, with the thickness of every third rib increased.

[0039] A cylindrical boss 66 is provided at one vertical end of some of the thick ribs 62 at the intersection with the horizontal wall portion 42 or the horizontal wall portion 46. A cylindrical boss 68 is provided at one vertical end of some of the thick ribs 64 at the intersection with the horizontal wall portion 44. The vertical walls 38, 40 constituting the closed cross-sectional portion 34 each have a boss 70 provided at the intersection with the horizontal wall portion 46.

[0040] These bosses 66, 68, 70 serve as seats against which ejector pins (not shown) abut when releasing a casting including the front side member 16 from a mold. For this reason, the bosses 66, 68, 70 are positioned offset in the vehicle front-to-rear direction so as not to overlap in the vertical direction, so that the casting can be released from the mold in a balanced manner. Note that the bosses 66, 68, 70 may also be used as seats for fastening to other components in addition to their function as seats against which ejector pins abut.

[0041] (high load area) In the upper and lower sections 48 and 50 of the high load area 30, similar to the low load area 28, vertical ribs 58 and 60 are respectively provided between the horizontal wall section 42 and the horizontal wall section 46, and between the horizontal wall section 46 and the horizontal wall section 44 in the vertical direction. In the upper and lower sections 48 and 50 of the high load area 30, similar to the low load area 28, thick ribs 62 and 64 and bosses 66, 68 and 70 are respectively provided.

[0042] Furthermore, a closed cross-sectional portion 72 that is triangular in a side view of the vehicle is provided below the high load area 30. This closed cross-sectional portion 72 is provided with an inclined portion 74 that branches off from the lateral wall portion 44 of the low load area 28 and inclines downward as it extends toward the rear of the vehicle, and the rear wall portion 36 and the vertical wall portion 40 that constitute the closed cross-sectional portion 34 each extend to the inclined portion 74.

[0043] In this manner, in this embodiment, the high load area 30 is provided with a closed cross-sectional portion 72 in addition to the closed cross-sectional portion 34, so that the cross-sectional height along the vehicle vertical direction gradually increases as it moves from the low load area 28 to the fracture suppression area 32.

[0044] Further, a lateral wall portion 76 is provided at the lower end side of the closed cross-sectional portion 72, branching off from the inclined portion 74 and formed substantially parallel to the lateral wall portion 44. Furthermore, vertical ribs 78 are provided between the lateral wall portion 44 and the inclined portion 74, and between the lateral wall portion 44 and the lateral wall portion 76. Here, the vertical ribs 78 are provided continuous with the vertical ribs 60 provided in the lower portion 50 of the high load area 30, but may be arranged offset in the vehicle longitudinal direction so as not to overlap in the vertical direction.

[0045] (destruction control area) On the other hand, the collapse suppression area 32 is formed with a stroke that is shorter than that of the low load area 28 and longer than that of the high load area 30, and the collapse suppression area 32 has a substantially rectangular closed cross-sectional portion 80 whose longitudinal direction is the vertical direction of the vehicle in a side view of the vehicle. The closed cross-sectional portion 80 is formed adjacent to the closed cross-sectional portions 34 and 72, and the vertical wall portions 40 of the closed cross-sectional portion 34 and the closed cross-sectional portion 72 are vertical wall portions erected at the front ends of the closed cross-sectional portion 80.

[0046] Additionally, the rear wall portions 36 constituting the closed cross-sectional portions 34, 72 are each formed contiguous with the rear wall portion 36 of the closed cross-sectional portion 80. Furthermore, the front portion of the lower end of the rear wall portion 36 of the closed cross-sectional portion 80 is formed contiguous with the closed cross-sectional portion 34 and the inclined portion 74 of the closed cross-sectional portion 72, and the rear portion of the closed cross-sectional portion 80 has a lateral wall portion 82 formed along the vehicle longitudinal direction.

[0047] Furthermore, the vertical wall portion 84 erected at the rear end of the closed cross-sectional portion 80 in the vehicle longitudinal direction is formed in the shape of a circular hole along the shape of the wheelhouse 22 (see FIG. 1). That is, the closed cross-sectional portion 80 is made up of the rear wall portion 36, the vertical wall portions 40, 84, the lateral wall portion 42, the inclined portion 74, and the lateral wall portion 82. Furthermore, the cross-sectional height of the crushing suppression area 32 in the vehicle vertical direction is greater than the cross-sectional heights of the low load area 28 and the high load area 30.

[0048] Additionally, the horizontal wall portions 44, 46, 76 of the high load area 30 extend to the crushing suppression area 32 and are connected to the vertical wall portion 84. Furthermore, a horizontal wall portion 86 is provided at approximately the center of the horizontal wall portions 76 and 82 in the up-down direction.

[0049] Here, a cylindrical or columnar boss 88 is provided on the front side of the lateral wall portion 46 in the vehicle longitudinal direction in the crush suppression area 32, and the boss 88 has a larger diameter than the bosses 70 provided in the high load area 30, etc. Furthermore, the lateral wall portion 46 is provided with the boss 70 between the boss 88 and the vertical wall portion 84.

[0050] The bosses 88 are provided at the intersections of the vertical wall portions 40 and the horizontal wall portions 44 in the destruction suppression area 32 and on the rear side of the horizontal wall portions 44 in the vehicle longitudinal direction, and the bosses 70 are provided between the bosses 88. Furthermore, a boss 88 is provided on the front side of the horizontal wall portions 76 in the destruction suppression area 32 in the vehicle longitudinal direction, and the boss 70 is provided between the boss 88 and the vertical wall portion 84. Furthermore, a boss 70 is provided on the front side of the horizontal wall portion 86 in the vehicle longitudinal direction, and the boss 88 is provided between the boss 70 and the vertical wall portion 84.

[0051] In the fracture suppression area 32, the intersection of the vertical wall portion 40 and the horizontal wall portion 42 and the intersection of the horizontal wall portion 76 and the vertical wall portion 84 are connected by a linear inclined rib 90. A boss 88 provided on the horizontal wall portion 46 and a boss 88 provided on the horizontal wall portion 44 are respectively provided on this inclined rib 90. In other words, a boss 88 is provided at each of the points where the inclined rib 90 intersects with the horizontal wall portions 44, 46.

[0052] Furthermore, the intersection of the horizontal wall portion 42 and the vertical wall portion 84 and the boss 88 provided on the horizontal wall portion 46 are connected by a linear inclined rib 92 .

[0053] Furthermore, a boss 88 is provided at the intersection of the vertical wall portion 40 and the horizontal wall portion 44, and the boss 88 provided on the horizontal wall portion 46 is connected to the boss 88 by a linear inclined rib 94. Furthermore, the intersection of the horizontal wall portion 46 and the vertical wall portion 84 is connected to the boss 88 provided on the horizontal wall portion 44 by a linear inclined rib 96.

[0054] Furthermore, in the fracture suppression area 32, a boss 88 provided at the intersection of the vertical wall portion 40 and the horizontal wall portion 44 and the intersection of the horizontal wall portion 82 and the vertical wall portion 84 are connected by a linear inclined rib 98. A boss 88 provided on the horizontal wall portion 44 and a boss 88 provided on the horizontal wall portion 86 are also provided on this inclined rib 90. As with the inclined rib 90, when turned over, a boss 88 is provided at each of the points where the inclined rib 98 intersects with the horizontal wall portions 76, 86. Note that the inclined rib 98 further has a boss 88 provided between the intersection of the horizontal wall portion 82 and the vertical wall portion 84 and the horizontal wall portion 86.

[0055] Meanwhile, a boss 88 provided on the rear side of the lateral wall portion 44 in the vehicle longitudinal direction and a boss 88 provided on the lateral wall portion 76 are connected by a linear inclined rib 100, and the intersection of the boss 88 provided on the lateral wall portion 76, the vertical wall portion 40, and the inclined portion 74 is connected by a linear inclined rib 104. Furthermore, the boss 88 provided on the lateral wall portion 86 is connected by a linear inclined rib 106 to the intersection of the lateral wall portion 76 and the vertical wall portion 84. Furthermore, the intersection of the boss 88, the inclined portion 74, and the lateral wall portion 82 is connected by a linear inclined rib 108.

[0056] In this way, in the destruction suppression area 32, for example, the vertical wall portion 40, the horizontal wall portion 46, and the inclined rib 90, and the horizontal wall portion 42 and the inclined ribs 90, 92 each form a triangular shape and are formed continuously to form the truss structure 110. In this embodiment, in addition to these, the vertical wall portion, the horizontal wall portion, and the inclined ribs also form continuous triangular shapes at each location, resulting in a truss structure 110 consisting of multiple stages (here, five stages).

[0057] <Actions and effects of the body structure> Next, the operation and effects of the vehicle body structure according to this embodiment will be described.

[0058] As shown in FIG. 3, in this embodiment, the shock absorbing section 14 is configured to include multiple areas (low load area 28, high load area 30, and fracture suppression area 32) corresponding to the stroke in response to the input of the impact load F, and the multiple areas (low load area 28, high load area 30, and fracture suppression area 32) have different load-bearing capacities in response to the input of the impact load F.

[0059] As a result, in this embodiment, the impact absorbing unit 14 can control the load in response to the stroke relative to the input of the impact load F. In other words, in this embodiment, the breaking load (withstand load) at the time of a collision of the vehicle 10 can be controlled by the impact absorbing unit 14. As a result, in this embodiment, the impact absorbing unit 14 can effectively absorb impact energy in response to the stroke relative to the input of the impact load F, and can suppress the impact load F from entering the vehicle interior 11 (see FIG. 1).

[0060] Specifically, in this embodiment, the impact absorbing section 14 is provided with a low load area 28, a high load area 30, and a destruction suppression area 32 along the input direction of the impact load F, and the load-bearing capacity against the input of the impact load F increases in the order of the low load area 28, the high load area 30, and the destruction suppression area 32.

[0061] Therefore, the impact energy of the impact load F input from outside the vehicle can be absorbed in stages from the low load area 28 to the high load area 30 in the impact absorbing section 14 before it is transmitted from the outside to the inside of the vehicle, thereby reducing the breaking load and the deceleration G. Therefore, it is possible to prevent a large impact from being input to the occupant.

[0062] In addition, in this embodiment, the cross-sectional height of the crush suppression area 32 in the vehicle vertical direction is greater than the cross-sectional heights of the low load area 28 and the high load area 30, and the cross-sectional modulus is higher and the second moment of area is greater than those of the low load area 28 and the high load area 30. Therefore, in this embodiment, the crush suppression area 32 has a higher bending rigidity than the low load area 28 and the high load area 30, making it possible to suppress deformation and to suppress the impact load F from entering the vehicle interior 11 (see FIG. 1 ).

[0063] Furthermore, in this embodiment, the shock absorbing part 14 has vertical ribs 58, 60 extending in the up-down direction between the horizontal wall part 42 and the horizontal wall part 46, and between the horizontal wall part 46 and the horizontal wall part 44. This increases the rigidity of the shock absorbing part 14, improves the load resistance, and enables the amount of impact energy absorption to be improved.

[0064] In this embodiment, the longitudinal ribs 58, 60 are arranged in multiple rows along the vehicle longitudinal direction, and the longitudinal ribs 58 and 60 are arranged offset in the vehicle longitudinal direction and are not continuous in the up-down direction. This causes the timing of failure due to the longitudinal ribs 58, 60, etc. to differ, making it possible to reduce the failure load compared to when the timing of failure due to the longitudinal ribs 58, 60, etc. is the same. Therefore, in this embodiment, it is possible to further reduce the load difference in the failure load, and it is possible to reduce the impact value experienced by occupants in the event of failure.

[0065] In this embodiment, the pitch of the longitudinal ribs 58, 60 becomes shorter from the front end to the rear end of the low load area 28. As a result, in this embodiment, the span of Euler buckling becomes smaller from the front end to the rear end in the low load area 28, and the crushing load can be increased accordingly.

[0066] Therefore, in this embodiment, in the low-load area 28, the crushing load (withstand load) gradually increases from the front end to the rear end of the low-load area 28. This makes it possible to gradually increase the amount of impact energy absorbed in the low-load area 28, preventing a large impact from being input to the occupant.

[0067] Note that, as long as the crushing load gradually increases from the front end to the rear end of the low load area 28, not only the pitch of the vertical ribs 58, 60 but also the thickness may be changed, or both may be applied. Furthermore, the plate thickness of the lateral wall portions 42, 44, 46 may be gradually increased from the front end to the rear end of the low load area 28.

[0068] Furthermore, in this embodiment, in the high load area 30, the cross-sectional height along the vehicle vertical direction gradually increases from the low load area 28 to the crush prevention area 32. Therefore, in the high load area 30, the rigidity gradually increases from the low load area 28 to the crush prevention area 32. This makes it possible to gradually increase the amount of impact energy absorbed in the high load area 30 and prevent a large impact from being input to the occupant.

[0069] As a result of the above, in the shock absorbing section 14, at least the low load area 28 and the high load area 30, the load capacity gradually increases along the input direction of the impact load F. This makes it possible to crush the shock absorbing section 14 sequentially from the front end to the rear end in the input direction of the impact load F. In other words, the shock absorbing section 14 is able to suppress residual crushing and efficiently absorb impact energy sequentially from the front end to the rear end of the shock absorbing section 14.

[0070] In this embodiment, the front side members 16 are formed by casting. This allows for greater freedom in designing the shape of the front side members 16 and improves manufacturing efficiency compared to, for example, molding by extrusion.

[0071] Furthermore, in this embodiment, the left and right front side members 16, the left and right wheel houses 22, and the cross member 24 are integrally formed by casting. As a result, in this embodiment, fasteners for fastening the left and right front side members 16 to the left and right wheel houses 22, and the left and right wheel houses 22 to the cross member 24, respectively, are not required, making it possible to reduce the number of parts. However, these members do not necessarily have to be integrated, and of course, they may each be formed as a single unit.

[0072] In the above embodiment, the front side member 16 is formed by casting, but the present invention is not limited to this. For example, the front side member 16 may be formed from CFRP (carbon fiber reinforced plastic) instead of metal. In this case, the front side member 16 is formed by injection molding, for example.

[0073] Furthermore, in the above embodiment, the front side member 16 has been described, but the present invention can be applied to other components besides the front side member 16. For example, the present invention may be applied to other frame members such as the rocker 112, the rear side member 114 (see FIG. 1), and a suspension member (not shown). The input direction of the impact load will vary depending on the frame member to which it is applied. Furthermore, since it is sufficient to provide multiple areas with different load resistance in the impact absorbing portion, two areas may be used.

[0074] In the present embodiment, the shock absorbing section 14 has increasing load resistance against the input of the impact load F in the input direction of the impact load F in the order of the low load area 28, the high load area 30, and the destruction suppression area 32, but this is not necessarily limited to this. For example, the order may be changed by changing the stroke of each area.

[0075] Although one embodiment of the present invention has been described above, the present invention is not limited to such an embodiment, and one embodiment may be appropriately combined with various modified examples, and the present invention may of course be embodied in various forms as long as it does not deviate from the gist of the present invention.

[0076] <Additional Notes> The vehicle body structure according to the present invention may be formed by appropriately combining the following configurations.

[0077] (Configuration 1) The shock absorbing portion is configured to include a plurality of areas with different load resistances corresponding to the stroke of the input of the shock load.

[0078] (Configuration 2) The impact absorbing section has a low load area, a high load area, and a destruction suppression area along the input direction of the impact load, and the load capacity increases in the order of the low load area, the high load area, and the destruction suppression area.

[0079] (Configuration 3) In the impact absorbing portion, the cross-sectional height of the destruction suppression area in the vehicle vertical direction is greater than the cross-sectional heights of the low load area and the high load area.

[0080] (Configuration 4) The impact absorbing portion is arranged along the fore-and-aft direction of the vehicle, and is made up of multiple ribs arranged along the fore-and-aft direction of the vehicle, spanning between the upper wall portion and the lower wall portion that form part of the low load area, with the rigidity increasing from the front end to the rear end of the low load area.

[0081] (Configuration 5) In the high load area, the cross-sectional height along the vehicle up-down direction gradually increases from the low load area to the destruction suppression area. [Explanation of symbols]

[0082] 10 vehicles 12 Body structure 14 Shock absorbing part 16 Front side member (impact absorbing part) 18 Crash box (shock absorbing part) 26 Destruction start area (shock absorption area) 28 Low load area (area, shock absorbing part) 30 High load area (area, shock absorbing part) 32 Destruction suppression area (area, shock absorbing part) 42 Side wall (upper wall) 44 Side wall (lower wall) 58 Vertical rib (rib) 60 Vertical rib (rib) 62 Thick rib (rib) 64 Thick Rib (Rib) 112 Rocker (shock absorbing part) 114 Rear side member (impact absorbing part) F Impact load

Claims

1. A vehicle body structure provided with an impact absorbing section that includes a plurality of areas with different load resistance corresponding to the stroke of the input of an impact load.

2. 2. The vehicle body structure according to claim 1, wherein the impact absorbing portion includes a low load area, a high load area, and a destruction suppression area along the input direction of the impact load, and the load capacity increases in the order of the low load area, the high load area, and the destruction suppression area.

3. The vehicle body structure according to claim 2 , wherein the cross-sectional height of the destruction suppression area in the vehicle vertical direction is greater than the cross-sectional heights of the low load area and the high load area.

4. 3. The vehicle body structure according to claim 2, wherein the impact absorbing portion is provided along the longitudinal direction of the vehicle, and the impact absorbing portion is a plurality of ribs arranged along the longitudinal direction of the vehicle, spanning between an upper wall portion and a lower wall portion that constitute a part of the low load area, the rigidity of which increases from the front end to the rear end of the low load area.

5. 3. The vehicle body structure according to claim 2, wherein the high load area has a cross-sectional height along the vehicle vertical direction that gradually increases from the low load area toward the destruction suppression area.

Images