Vehicle body end part structure

Abstract

According to one embodiment, a vehicle body end part structure 1 comprises: an elongate bumper reinforcement 2 that is disposed at an end part in the front-rear direction of a vehicle body and extends in the vehicle width direction; a side member 3 that is disposed inward in the front-rear direction relative to the bumper reinforcement 2 and extends in the front-rear direction; and a suspension member 4 disposed below the side member 3. A deformation member 6 extending outward in the vehicle width direction from the side member 3 is provided at a longitudinal end part 2b of the bumper reinforcement 2, and a vertical column body 7 extending downward so as to be connected to the suspension member 4 is provided on an outer surface in the vehicle width direction of the side member 3. The deformation member 6 deforms in the collision direction upon receiving a collision load, and comes into contact with the vertical column body 7, whereby the collision load is transmitted.

Description

Body end structure

[0001] The technology disclosed in this application relates to a vehicle body end structure.

[0002] One of the collision safety requirements for vehicles such as automobiles is protection against small overlap collisions. A small overlap collision is defined, for example, in safety evaluation tests conducted by the Insurance Institute for Highway Safety (IIHS) in the United States as an offset collision in which the overlap amount between the vehicle and the other vehicle in the width direction is 25% or less. In relation to this, conventionally known structures include those that absorb the collision load during a small overlap collision to reduce the impact force, and those that convert a portion of the collision load into a lateral force and transmit it to a rear member to move the vehicle away from a barrier.

[0003] For example, U.S. Patent No. 9,567,010 discloses a vehicle front structure including a pair of side members and a front bumper connecting the side members. The side members are fitted with reinforcing members extending diagonally forward. In the event of a small overlap collision, the end of the front bumper deforms and comes into contact with the reinforcing members, thereby transmitting the load from the barrier to the side members.

[0004] The vehicle front body structure disclosed in European Patent No. 2987705 includes a pair of side members and a front bumper connecting the side members. Pressure-receiving portions are provided on the sides of the side members, and end members are attached to the vehicle width ends of the front bumper. When the front bumper receives a collision load from the barrier and bends, the end members come into contact with the pressure-receiving portions of the side members. In the event of a small overlap collision, the end members come into contact with the pressure-receiving portions, transmitting the collision load from the barrier to the power unit via the side members. This structure offers improved strength and rigidity compared to the structure of the U.S. patent, in which the collision load is borne solely by the side members.

[0005] However, with the structure described in the above European patent, depending on the bending position of the front bumper, the end member may not come into contact with the pressure-receiving portion of the side member. Furthermore, from immediately after the barrier collides until the barrier, the end member, and the pressure-receiving portion are connected in series, the collision load is not easily transmitted, and the lateral force tends to be small. Therefore, there is a need for an improved collision load transmission efficiency. It is desirable to provide a vehicle body end structure that can efficiently move the vehicle away from the barrier during a small overlap collision.

[0006] One aspect of the present technology is a vehicle body end structure provided at the front or rear of a vehicle body, comprising: a long bumper reinforcement disposed at an end in the fore-and-aft direction of the vehicle body and extending in the vehicle width direction; a side member disposed inward in the fore-and-aft direction from the bumper reinforcement and extending in the fore-and-aft direction; a suspension member disposed below the side member; a deformable member extending outward in the vehicle width direction from the side member at a longitudinal end of the bumper reinforcement; and a vertical pillar attached to the vehicle width outer surface of the bumper reinforcement side end of the side member and extending downward from the side member so as to be connected to the suspension member, wherein when the deformable member is deformed in the collision direction due to a collision load, the deformable member abuts against the vertical pillar.

[0007] In some embodiments, the deformable member is arranged between a crash box attached to the tip of the side member and the bumper reinforcement, and is composed of a strength member that supports the bumper reinforcement from the inside.

[0008] In some embodiments, the vertical pillar has a pressure-receiving surface formed on the outer side in the vehicle width direction than the side member, and the deformable member has a contact surface formed on the inner side in the front-to-rear direction and that contacts the pressure-receiving surface when it receives a collision load and deforms in the collision direction.

[0009] In some embodiments, the vertical column is a hollow body, and has a reinforcing member disposed in the hollow body so as to separate an internal space into upper and lower spaces at a position corresponding to the pressure-receiving surface.

[0010] In some embodiments, the vertical pillar has a protruding portion that protrudes outward beyond the side member in the vehicle width direction, and the pressure receiving surface is located at a protruding end of the protruding portion.

[0011] In some embodiments, a vehicle body end structure can be provided that can efficiently move the vehicle body away from the barrier in the event of a small overlap collision.

[0012] 7 is a perspective view showing an outline of a vehicle body end structure according to one embodiment. FIG. 8 is a plan view of the vehicle body end structure. FIG. 9 is a cross-sectional view of the vehicle body end structure of FIG. 2 taken along line III-III. FIG. 10 is a cross-sectional view of the vehicle body end structure of FIG. 2 taken along line IV-IV. FIG. 11 is an assembly (exploded) view of the suspension member and vertical pillar body on the left side of the vehicle body end structure. FIG. 12 is a side view of the vehicle body end structure of FIG. 2 taken in the direction of arrow VI. FIG. 13 is a diagram schematically showing the state of a deformed member during a small overlap collision. FIG. 14 is a diagram schematically showing the state of a deformed member further deformed from the state shown in FIG. 7.

[0013] Various embodiments will be described below with reference to the drawings.

[0014] <Vehicle Body End Structure> Figure 1 shows a vehicle body end structure 1 according to one embodiment. Note that the up-down, front-rear, and left-right directions in the following description are directions relative to the vehicle. Also, the following description will be given assuming that the vehicle body end structure 1 is disposed at the front end of the vehicle, but a vehicle body end structure disposed at the rear end can also be configured in the same way.

[0015] 1, the vehicle body end structure 1 includes a (front) bumper reinforcement 2 provided at the front end of the vehicle body, side members 3 provided on both the left and right sides rearward of the bumper reinforcement 2, and a suspension member 4 disposed below the side member 3. Crash boxes 5 are disposed between the front end portions 31 (tips) of the left and right side members 3 and the bumper reinforcement 2.

[0016] <Bumper Reinforcement> The bumper reinforcement 2 is an elongated structural member extending in the vehicle width direction. The bumper reinforcement 2 can be formed by press-forming a steel plate. As shown in FIG. 2, in a plan view, the left and right longitudinal ends 2b of the bumper reinforcement 2 can be gently curved rearward. Furthermore, as shown in FIG. 3, the cross section of the bumper reinforcement 2 perpendicular to the longitudinal direction can be, for example, generally hat-shaped. Specifically, the bumper reinforcement 2 can have a shape that includes a recess 12 recessed rearward in the vertical center, protrusions 13 formed on both the upper and lower sides of the recess 12, and flanges 14.

[0017] <Deformable Member (Strength Member)> As shown in Figure 2, a deformable member 6 is provided at each end 2b of the bumper reinforcement 2, extending to a position further outward than the side member 3 in the vehicle width direction. The deformable member 6 is a strength member such as a steel plate member that is stronger than the bumper reinforcement 2, and can be made to have greater strength than the central portion 2a of the bumper reinforcement 2 in the longitudinal direction, for example. The deformable member 6 is disposed between the crash box 5 and the bumper reinforcement 2, and supports the bumper reinforcement 2 from the rear side. In other words, the deformable member 6 is disposed behind the bumper reinforcement 2 and is connected to the crash box 5.

[0018] As shown in FIGS. 3 and 4 , the cross-sectional shape of the deformable member 6 perpendicular to the longitudinal direction can be made to substantially match the cross-sectional shape of the end 2 b of the bumper reinforcement 2. This allows the deformable member 6 and the end 2 b of the bumper reinforcement 2 to overlap. The bumper reinforcement 2 and the deformable member 6 can then be fixed to the front end of the crash box 5 with a bolt 16 and a nut 17. For example, the bolt 16 can penetrate from the upper surface 18 to the lower surface 19 of the bumper reinforcement 2. In another embodiment (not shown), instead of the through bolt 16, separate bolts may be fastened to the upper surface 18 and the lower surface 19. When subjected to a load due to a small overlap collision of the vehicle, the deformable member 6 deforms in the collision direction. Specifically, as shown in FIG. 7 , the deformable member 6, which receives a collision load from the barrier B, deforms so as to bend rearward from the vicinity of the connection point with the crash box 5.

[0019] As shown in FIG. 4 , the deforming member 6 may have a generally M-shaped cross section in the vertical direction. This increases the strength of the deforming member 6. Specifically, a generally U-shaped recess 23 recessed toward the inside of the vehicle body is formed in the vertical center of the deforming member 6, and protrusions 24 are formed on both the top and bottom sides of the recess 23. Furthermore, as shown in FIG. 2 , the M-shaped top plate portion 25 and bottom plate portion 26 of the deforming member 6 have a tapered shape in which their widths narrow toward their tips (the outer ends in the vehicle width direction) in a plan view. Furthermore, the length of the deforming member 6 extending outward in the vehicle width direction is set to a length that ensures reliable contact with the vertical pillars 7 attached to the side members 3 when the deforming member 6 is bent as shown in FIG. 7 due to a collision load. Furthermore, the vertical wall of the recess 23 of the deforming member 6 is formed flat and functions as an abutment surface 27 that abuts against a pressure-receiving surface 38 of the vertical pillar 7, which will be described later.

[0020] <Side Member> As shown in Figures 1 and 2, the side member 3 is a frame member of the vehicle body that is disposed rearward of the bumper reinforcement 2 in the longitudinal direction of the vehicle. The side member 3 is elongated and extends in the longitudinal direction of the vehicle, and is disposed on both the left and right sides of the vehicle body as front side members. As shown in Figure 5, the side member 3 can be formed, for example, by welding together two press-formed steel plate members that are separated into left and right halves. The cross section of the side member 3 perpendicular to the longitudinal direction can be a closed shape such as a polygon (e.g., octagon), and can have an inwardly concave shape.

[0021] <Vertical pillar> A vertical pillar 7 is disposed at each front end 31 of the left and right side members 3. As shown in FIG. 5 , the vertical pillar 7 is a hollow member formed, for example, by welding two separate, front and rear, press-formed steel plate members together. Specifically, the vertical pillar upper portion 7a of the vertical pillar 7 is attached to the end of the side member 3 on the bumper reinforcement 2 side, i.e., to the vehicle width direction outer surface 32 of the front end 31, and the vertical pillar lower portion 7b extends downward from the side member 3. The vertical pillar upper portion 7a has a fitting portion 36 formed in a substantially U-shape, and the vertical pillar 7 is attached to the side member 3 from the vehicle width direction outer side. Furthermore, as shown in FIG. 2 , the vertical pillar upper portion 7a has a substantially trapezoidal shape in a plan view and has a protruding portion 37 that protrudes outward in the vehicle width direction of the side member 3. A flat pressure-receiving surface 38 is formed at the protruding end of the protruding portion 37.

[0022] 6, the vertical pillar 7 is disposed so as to face the suspension member 4 in the vehicle width direction. The lower end of the vertical pillar lower part 7b is connected to the suspension member 4 by, for example, a connecting bolt 35. With this configuration, the vertical pillar 7 and the suspension member 4 are capable of relative movement in the up-down direction, but are restricted from relative movement in the vehicle width direction.

[0023] The vertical pillar 7 is configured to have enough rigidity so as not to deform significantly during a collision. As shown in Fig. 5, a reinforcing member 39 that divides the internal space into upper and lower parts is disposed inside the hollow body of the vertical pillar 7 at a position corresponding to the pressure-receiving surface 38. The reinforcing member 39 is, for example, a metal member formed into a roughly U-shape, and is positioned near the lower side of the pressure-receiving surface 38 so that the central surface of the U-shape intersects with the up-down direction of the vertical pillar 7.

[0024] <Crash Box> The crash box 5 is disposed behind the bumper reinforcement 2 in the longitudinal direction of the vehicle. For example, when a collision load is applied to the front of the vehicle, the crash box 5 undergoes compressive deformation to absorb the energy. As shown in Figure 5, the crash box 5 is cylindrical and is formed, for example, by pressing two left and right halves of a steel plate member and welding them together into a single unit. The cross section of the crash box 5 perpendicular to the longitudinal direction is a closed polygonal shape (for example, an octagonal shape) and has an inwardly concave shape.

[0025] <Suspension Member> As shown in Figures 1 and 2, the suspension member 4 is disposed below the side members 3 and supports the vehicle body relative to the undercarriage components of the vehicle. The suspension member 4 is made of a metal material such as steel, and is configured in a frame shape including a pair of side rails 42, 43 extending in the front-rear direction on both the left and right sides, and two cross members 45, 46 connecting these side rails 42, 43. As shown in Figure 6, the lower ends of the vertical pillars 7 are connected to the front ends of the left and right side rails 42, 43, respectively.

[0026] <Advantageous Effects of the Embodiment> Next, advantageous effects of the above-described embodiment will be described.

[0027] As shown in Figure 7 , during a small overlap collision, the deformable member 6 (strength member) that receives the collision load deforms so as to bend rearward from the vicinity of the connection point with the crash box 5. The bent deformable member 6 abuts against the vertical pillar 7, forming a beam-like structure that spans between the tip of the crash box 5 and the vertical pillar 7, and the collision load is transmitted to the side member 3 and suspension member 4 via the vertical pillar 7. As a result, a lateral force F acts toward the side member 3 on the side opposite the collision side of the vehicle body, moving the vehicle away from the barrier B. Furthermore, as shown in Figure 8 , even after the deformable member 6 is bent and deformed, the vertical pillar 7 does not deform significantly and transmits the collision load. In this way, by generating a lateral force F on the suspension member 4 during a barrier collision and reducing the energy absorbed by the vehicle body, the effect of the vehicle being thrown past the barrier B can be obtained.

[0028] When the deformable member 6 of the bumper reinforcement 2 receives the load of a barrier collision, it deforms so as to bend around the tip of the crash box 5. Therefore, even if there is variation in the position where the barrier B hits, the variation in the bending position of the bumper reinforcement 2 can be kept small. Furthermore, because the member 6 has a sufficient length, the deformable member 6 can be reliably abutted against the vertical pillar 7, even if the bending position of the bumper reinforcement 2 or the deformation state of the crash box 5 varies depending on the position where the barrier B hits. Then, when the deformable member 6 abuts against the vertical pillar 7, the collision load from the barrier B is transmitted to the side member 3. At this time, the deformable member 6 acts as a beam spanning between the tip of the crash box 5 attached to the side member 3 and the vertical pillar 7 to receive the barrier B, so it can transmit a large load from the early stage of the collision. In other words, a large load can be transmitted without waiting for the barrier B, the deformable member 6, and the vertical pillar 7 to be connected in series. Therefore, the efficiency of transmission of the collision load can be improved, and the vehicle can be efficiently moved away from the barrier B in the event of a small overlap collision.

[0029] Due to the configuration in which the vertical pillars 7 are connected to the suspension members 4, the collision load is also transmitted to the suspension members 4 via the vertical pillars 7. That is, in addition to the paths through which the collision load is transmitted to the bumper reinforcement 2 and the side members 3, a path is formed through which the collision load is transmitted to the suspension members 4 via the vertical pillars 7. This improves the strength and rigidity against loads in the lateral direction of the vehicle body.

[0030] The deformable member 6 of the bumper reinforcement 2 is set to a length extending outward in the vehicle width direction so that, when subjected to a collision load, it bends from a base point near the connection point with the crash box 5 and reliably abuts against the vertical pillar 7 attached to the side member 3. By suppressing the variation in the base point of bending of the deformable member 6, it is possible to set the deformable member 6 to an appropriate length. In other words, there is no need to make the deformable member 6 excessively long, and an increase in the weight of the member can be suppressed, thereby making it possible to reduce the weight of the member.

[0031] When the deformable member 6 is deformed by bending due to a collision load, the abutment surface 27 of the deformable member 6 and the pressure-receiving surface 38 of the vertical pillar 7 come into contact with each other. Therefore, the deformable member 6 abuts against the vertical pillar 7 more reliably, and the load is transmitted. This further improves the load transmission efficiency.

[0032] In a plan view, the top plate portion 25 and the bottom plate portion 26 of the deforming member 6 have a tapered shape, with the widths of the top plate portion 25 and the bottom plate portion 26 narrowing toward the tip (the outer end in the vehicle width direction). This makes it easier for the abutment surface 27 of the deforming member 6 to abut against the pressure-receiving surface 38 of the vertical pillar 7 from the early stage of a collision, allowing a beam to be formed. This further improves the load transmission efficiency.

[0033] The vertical pillar 7 has a protruding portion 37 that protrudes outward from the side member 3 in the vehicle width direction, and a pressure-receiving surface 38 is located at the protruding end of the protruding portion 37. This makes it easier for the abutment surface 27 of the deformable member 6 and the pressure-receiving surface 38 of the vertical pillar 7 to abut against each other in the early stage of a collision, thereby forming a beam. This further improves the load transmission efficiency.

[0034] The vertical pillar 7 is made hollow, which allows for a reduction in the weight of the component. Furthermore, a reinforcing member 39 is provided inside the hollow body of the vertical pillar 7 and is located below the pressure-receiving surface 38. This prevents the cross section of the vertical pillar 7 from being crushed and deformed during a small overlap collision. Therefore, the rigidity and strength of the hollow vertical pillar 7 can be ensured.

[0035] The vertical pillars 7 are constructed to have enough strength to prevent large deformation such as crushing during a collision. This makes it possible to reduce the absorption of the collision load from the initial stage of the collision until after the deformation of the deformable members 6, and the deformable members 6 abutting against the vertical pillars 7 act as beams to efficiently transmit the collision load. In other words, a lateral force F can be efficiently generated, moving the vehicle away from the barrier B.

[0036] In the vehicle body end structure 1, the vertical pillars 7 are connected to the side members 3 and the suspension members 4. This eliminates the need for additional structural members to form a load transfer path. In other words, since the load transfer path does not include the power unit, it is not affected by the placement of the power unit. This increases the degree of freedom in vehicle body design.

[0037] <Other Embodiments> The vehicle body end structure 1 according to the above embodiment is configured to include a strength member as a deformation member 6 at the longitudinal end 2b of the bumper reinforcement 2. As another embodiment, instead of this, the bumper reinforcement may be formed from a single steel plate, for example, by joining steel plates of different thicknesses or materials using a tailored blank. In this case, for example, the plate thickness of the longitudinal end of the bumper reinforcement may be increased, resulting in a configuration having a deformation member with increased strength.

[0038] The bumper reinforcement 2 according to the above embodiment has a so-called forward hat cross section, with the central portion in the up-down direction recessed inward toward the vehicle body. The deformable member 6 is also formed with a cross section corresponding to the bumper reinforcement 2. In another embodiment, instead of this, a bumper reinforcement with a so-called reverse hat cross section, with the central portion in the up-down direction protruding outward toward the vehicle body, may be used. In this case, the deformable member is also formed with a cross section corresponding to the bumper reinforcement with a convex reverse hat cross section.

[0039] In various embodiments, the shape of the vertical pillar body, the attachment position relative to the side member, etc. are set appropriately according to the specifications of the vehicle, etc.

[0040] In another embodiment, the cross-sectional shape of the side member 3 and the crash box 5 may be other shapes such as a square or a hexagon instead of an octagonal polygon.

[0041] <Advantageous Effects of the Embodiment> Finally, the effects of the above embodiment will be summarized.

[0042] According to the above embodiment, the vehicle body end structure includes a deformable member extending outward in the vehicle width direction from the longitudinal end of the bumper reinforcement and a vertical pillar extending in the vertical direction on the vehicle width direction outer surface of the side member. With this configuration, when the deformable member receives a load due to a barrier collision, it deforms so as to bend in the collision direction. Because the deformable member has a sufficient length, the deformable member can reliably abut against the vertical pillar, even if the bending position of the bumper reinforcement or the deformation state of the tip of the side member varies depending on the position where the barrier hits. The abutment of the deformable member against the vertical pillar transmits the collision load from the barrier to the side member. Furthermore, because the vertical pillar is connected to the suspension member, the collision load is also transmitted to the suspension member via the vertical pillar. In other words, the configuration that transmits the collision load to the side member and the suspension member improves the strength and rigidity of the vehicle body against lateral loads. Furthermore, the deformable member serves as a beam spanning between the tip of the side member (or crash box) and the vertical pillar to receive the barrier, and is therefore able to transmit a large load from the initial stage of the collision. Therefore, the load transmission efficiency can be improved, and the vehicle can be efficiently moved away from the barrier in the event of a small overlap collision.

[0043] In some embodiments, the deformation member of the bumper reinforcement is composed of a strength member arranged between the bumper reinforcement and the crash box attached to the tip of the side member. Since the strength required differs between the longitudinal center and end portions of the bumper reinforcement, by making the deformation portion of the bumper reinforcement a separate member with higher strength, the strength of the bumper reinforcement can be appropriately increased as needed. In addition, the increase in the weight of the entire bumper reinforcement can be suppressed, allowing the member to be made lighter.

[0044] In some embodiments, the vertical pillar has a pressure-receiving surface formed on the outer side of the side member in the vehicle width direction, and the deformable member has a contact surface formed on the inner side in the front-to-rear direction. When the deformable member receives a collision load and deforms in the collision direction, the contact surface contacts the pressure-receiving surface of the vertical pillar. By configuring the deformable member and the vertical pillar to be in surface-to-surface contact, the deformable member can be more reliably brought into contact with the vertical pillar, thereby transmitting the collision load. Therefore, the efficiency of transmitting the load to the vehicle body is improved.

[0045] In some embodiments, the vertical pillar has a reinforcing member disposed within the hollow body. The reinforcing member is disposed at a position corresponding to the pressure-receiving surface so as to separate the internal space of the vertical pillar. This can prevent the cross section of the vertical pillar from being crushed and deformed during a small overlap collision. This improves the rigidity and strength of the vertical pillar 7, enabling it to transmit a larger load.

[0046] In some embodiments, the vertical pillar has a protruding portion that protrudes outward in the vehicle width direction from the side member, and the pressure-receiving surface is located at the protruding end of the protruding portion. This makes it easier for the abutment surface of the deformable member and the pressure-receiving surface of the vertical pillar to abut against each other from the early stage of a collision, allowing a beam to be formed. Therefore, the load transmission efficiency is further improved.

[0047] Although various embodiments have been described above, the present technology is not limited to these embodiments, and those skilled in the art can make various modifications, substitutions, and improvements.

Claims

1. A vehicle body end structure provided at the front or rear of a vehicle body, comprising: a long bumper reinforcement arranged at the front or rear end of the vehicle body and extending in the vehicle width direction; a side member arranged inward in the fore-and-aft direction from the bumper reinforcement and extending in the fore-and-aft direction; a suspension member arranged below the side member; a deformable member extending outward in the vehicle width direction from the side member at the longitudinal end of the bumper reinforcement; and a vertical pillar attached to the vehicle width outer surface of the bumper reinforcement side end of the side member and extending downward from the side member so as to be connected to the suspension member, wherein when the deformable member is deformed in the collision direction due to a collision load, the deformable member abuts against the vertical pillar.

2. A vehicle body end structure as described in claim 1, wherein the deformable member is arranged between a crash box attached to the tip of the side member and the bumper reinforcement, and is composed of a strength member that supports the bumper reinforcement from the inside.

3. A vehicle body end structure as set forth in claim 1 or claim 2, wherein the vertical pillar body has a pressure-receiving surface formed on the outside in the vehicle width direction of the side member, and the deformable member has a contact surface formed on the inside in the front-to-rear direction and that comes into contact with the pressure-receiving surface when it receives a collision load and deforms in the collision direction.

4. A vehicle body end structure as described in claim 3, wherein the vertical pillar body is a hollow body, and a reinforcing member is disposed within the hollow body so as to separate the internal space into upper and lower sections, at a position corresponding to the pressure-receiving surface.

5. A vehicle body end structure according to claim 4, wherein the vertical pillar has a protruding portion that protrudes outward in the vehicle width direction from the side member, and the pressure-receiving surface is located at the protruding end of the protruding portion.

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