WO2006068008A1

WO2006068008A1 - Bumper and shock absorbing structure of vehicle

Info

Publication number: WO2006068008A1
Application number: PCT/JP2005/022855
Authority: WO
Inventors: Masakazu Iketo; Masao Terazawa; Shunji Mashio; Mitsutoshi Kanoh; Katsutoshi Takagi
Original assignee: Aisin Seiki Kabushiki Kaisha; Toyota Jidosha Kabushiki Kaisha; Aisin Takaoka Co., Ltd.; Toyoda Iron Works Co., Ltd.
Priority date: 2004-12-24
Filing date: 2005-12-13
Publication date: 2006-06-29
Also published as: JP2006176093A

Abstract

A bumper and a shock absorbing structure of a vehicle. The bumper comprises a bumper frame (11) having a bumper reinforcement hose (16) extending in the lateral direction of the vehicle and a pair of hollow crush boxes (17) fixed to both ends of the bumper reinforcement hose and extending in the longitudinal direction of the vehicle. The bumper reinforcement hose is formed in a plate shape and comprises a main wall part (16a) extending in the vertical direction and a pair of opposed wall parts (16b, 16c) bent relative to the main wall part so as to extend from the upper and lower ends of the main wall part to the rear of the vehicle. The tip of each of the crush boxes is covered by the main wall part and fixed to the bumper reinforcement hose in the state of being held between the pair of opposed wall parts.

Description

Specification

Pumper and vehicle shock absorbing structure

Technical field

[0001] The present invention relates to a shock absorber for a bumper and a vehicle.

Background art

[0002] Conventionally, as a bumper for a vehicle, for example, one described in Patent Document 1 is known. The bumper includes a bumper inhose extending in the width direction of the vehicle, and a pair of crash boxes that are fixed to both ends of the bumper inn hose by bolts and extend in the vehicle front-rear direction. These bumper-in hoses and crash boxes have a hollow structure. For example, when a rearward load (impact) is applied to the van hose hose due to a vehicle collision, the load is transmitted to the crash box as an axial compression load after the bumper hose is bent and buckled. The crash box is plastically deformed in the axial direction by the transmitted load, thereby absorbing the impact energy associated with the vehicle collision. Therefore, the impact due to the vehicle collision is transmitted to the vehicle body and the occupant after being reduced by the bumper.

[0003] In the above-described bumper, an axial compressive load acting on the crash box is basically generated after the bumper-in hose is bent and buckled during a vehicle collision. As a result, the rise of the axial compression load acting on the crash box is delayed, and the impact energy absorption efficiency is reduced.

[0004] Specifically, Fig. 6 (a) shows the relationship between the load acting on the bumper rein hose (cross-section buckling load) and the stroke (deformation amount) of the bumper rein hose. ) Shows the relationship between the load acting on the crash box (axial compression load) and the stroke (deformation amount) of the crash box. Fig. 6 (a) shows the characteristics of the vannori hose alone, and Fig. 6 (b) shows the characteristics of the crash box alone. On the other hand, Fig. 6 (c) shows the relationship between the load acting on the bumper including these bumper-in hoses and crush boxes and the striker (deformation amount) of the bumper.

[0005] As shown in FIG. 6 (a), the cylindrical bumper inhose having a closed cross-sectional structure is Bending deformation until buckling start load Fl, and then buckling. On the other hand, as shown in Fig. 6 (b), the crash box starts buckling deformation when the axial compression load acting on the crash box reaches the buckling start load F2, and then continuously in a bellows shape. Repeat buckling deformation. The axial compression load when the crash box repeats buckling deformation changes at a relatively large value with respect to the load F1 when the pan-palliin hose starts buckling deformation.

[0006] As shown in Fig. 6 (c), as for the entire bumper including the van Nori hose and the crash box, the load acting on the bumper first reaches the buckling start load F1, and the bumperin hose is deformed. When the load acting on the bumper reaches the buckling start load F2, the crash box starts buckling deformation. As a result, the load acting on the bamba does not reach the buckling start load F2 quickly, and the impact energy absorption efficiency is reduced.

[0007] In order to compensate for the reduction in impact energy absorption efficiency, the force required to lengthen the crash box. This leads to an increase in the mounting space of the pump for the vehicle. In addition, the above-described bumper is configured by attaching a cylindrical bumper line hose having a closed cross-sectional structure to the ends of a pair of crash boxes. Therefore, the bumper inhose projects forward from the tip of the crash box by the width in the longitudinal direction of the vehicle. This also leads to an increase in the mounting space of the pump against the vehicle.

Patent Document 1: JP 2002-188673 A

Disclosure of the invention

[0008] An object of the present invention is to provide a bumper and a vehicle shock absorbing structure that can suppress an increase in mounting space and can efficiently absorb a shock caused by a vehicle collision.

In order to achieve the above object, the present invention provides a bumper inhose extending in the vehicle width direction, and a pair of hollow shapes extending in the front-rear direction of the vehicle fixed to both ends of the bumper inhose. Bamba with a crash box. The bumper-in hose has a plate shape, and is bent with respect to the main wall portion so as to extend from the upper and lower ends of the main wall portion toward the front or rear of the vehicle, respectively. A pair of opposing walls. The tip of each crash box is covered with the main wall and fixed to the bumper inn hose while being sandwiched between the pair of opposing walls. It is.

[0010] According to the present invention, for example, when an impact along the vehicle longitudinal direction is applied to the bumper hose due to a vehicle collision, the impact immediately follows the front and rear of the vehicle after the plate-like bumper in hose is slightly bent. It is transmitted to the crash box as a load in the direction (axial compression load). In other words, the axial compression load acting on the crash box rises immediately after the bumper inn hose is bent. As a result, the crash box is quickly plastically deformed in the axial direction (the longitudinal direction of the vehicle) by the transmitted load, and absorbs the impact energy accompanying the vehicle collision.

[0011] Further, by fixing the crash box to the bumper inn hose while being sandwiched between a pair of opposing walls, the length of the crash box in the longitudinal direction of the vehicle is secured as much as possible, It is possible to suppress an increase in the mounting space of the pump against the vehicle.

[0012] Further, the bumper inhose has a pair of opposing wall portions bent with respect to the main wall portion.

The cross-sectional second moment is increased. In such a configuration, for example, due to an offset collision with another vehicle, only one crash box fixed to one end of the van hose hose receives a load (axial compression load) in the longitudinal direction of the vehicle. Suppose that significant plastic deformation occurred. In this case, the crash box on the anti-collision side fixed to the other end of the bumper inhose is pulled through the vannoin hose. However, since the moment of inertia of the bumper rein hose is increased, the force S acting on the crash box on the side of the collision is acting on the crash box. The crash box on the collision side is pulled in the axial direction. Therefore, it is possible to suppress breakage of the joint portion between the crash box on the anti-collision side and the bumper in hose and the joint portion between the crash box on the anti-collision side and the vehicle body (side member, etc.). That is, it is possible to prevent the crash box on the anti-collision side from being detached from the bumper hose or the vehicle body due to the offset collision.

[0013] In one aspect of the present invention, the bumper-in hose is bent with respect to the corresponding opposing wall portion so as to extend in directions opposite to each other from the tips of the pair of opposing wall portions. It has a flange wall. [0014] The flange wall portion further increases the cross-sectional second moment of the vanno-hose. Therefore, at the time of the offset collision described above, it is more preferable to prevent the joint between the crash box on the anti-collision side and the bumper hose and the joint between the crash box on the anti-collision side and the vehicle body (side member, etc.). can do.

[0015] Each of the crash boxes has an upper wall portion and a lower wall portion facing each other, and a corner portion between the pair of opposed wall portions and the flange wall portion corresponding thereto corresponds to the upper wall portion and the lower wall portion, respectively. It may be welded to the lower wall portion.

[0016] With this configuration, the bumper inhose is directly fixed to the crash box without using a separate part such as a fixture, so the number of parts can be reduced.

In one aspect of the present invention, each of the crash boxes has an opening at the tip thereof, and a lid is fixed to each of the crash boxes so as to close the opening. The main wall portion is fastened to the lid using bolts and nuts, whereby the bumper hose is fixed to the crash boxes.

In another aspect of the present invention, each of the crash boxes has an upper wall portion and a lower wall portion facing each other, and the pair of opposed wall portions are bolts and nuts on the upper wall portion and the lower wall portion, respectively. It is concluded using.

[0019] The present invention also provides a vehicle in which a pair of hollow crush boxes are disposed between both ends of a bumper inhose extending in the width direction of the vehicle and a pair of side members extending in the front-rear direction of the vehicle. Provides shock absorbing structure. The bumper-in hose has a plate shape and is bent with respect to the main wall portion so as to extend in the vertical direction from the upper and lower ends of the main wall portion toward the front or rear of the vehicle. And a pair of opposing wall portions. The tip of each crash box is fixed to the bumper inn hose while being covered by the main wall and sandwiched between the pair of opposing walls. Brief Description of Drawings

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line 2-2 in FIG.

[Fig. 3] (a), (b), and (c) are graphs showing the relationship between load and stroke, respectively.

FIG. 4 is a cross-sectional view showing a modified example of the present invention. FIG. 5 is a cross-sectional view showing a modified example of the present invention.

[Fig. 6] (a), (b), and (c) are graphs showing the relationship between the load and the stroke in the conventional example, respectively. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view schematically showing a left side portion of a front portion of a vehicle or the like to which the present invention is applied, such as an automobile, and FIG. 2 is a line 2-2 in FIG. FIG. The front part of the vehicle is symmetrical, and the right part of the front part has the same shape as the left part shown in FIG.

As shown in FIG. 1, the front portion includes a bumper frame 11 that forms a skeleton of a bumper, and a pair of side members 12 that extend in the front-rear direction of the vehicle and constitute a part of the vehicle body (left side) Only the side member 12 is shown). The bumper frame 11 includes a bumper inhose 16 extending in the vehicle width direction and a pair of crash boxes 17 (only the left crash box 17 is shown).

As shown in FIG. 1 and FIG. 2, the bumper-in hose 16 is formed by bending a plate material made of, for example, a metal material (iron or the like). (In the width direction) has a substantially constant cross-sectional shape. The vanno-in hose 16 has an open cross-sectional structure. That is, the bumper hose 16 includes a main wall portion 16a extending in the vertical direction, a pair of substantially horizontal opposing wall portions 16b and 16c extending continuously from the upper end and the lower end of the main wall portion 16a, and the opposing wall portions. It has flange walls 16d and 16e which are almost vertical extending continuously from the tips of 16b and 16c. The opposing wall portions 16b and 16c are bent with respect to the main wall portion 16a so as to extend from the upper end and lower end of the main wall portion 16a toward the rear of the vehicle. The flange wall portions 16d and 16e are bent with respect to the corresponding opposing wall portions 16b and 16c so as to extend in directions opposite to each other from the front ends of the corresponding opposing wall portions 16b and 16c.

[0025] The pair of crash boxes 17 are arranged between both longitudinal ends of the bumper-in hose 16 and the corresponding side members 12. Specifically, as shown in FIG. 2, each of the crash boxes 17 extends in the front-rear direction of the vehicle and has a rectangular cross section. It has a hollow structure. The opening at the tip of the crash box 17 is closed by a lid 21. The lid 21 is formed into a channel shape in cross section by bending a plate made of, for example, a metal material (iron or the like). The lid 21 is substantially closed from the closed wall 21a and the upper and lower ends of the closed wall 21a. A pair of mounting wall portions 21b bent with respect to the blocking wall portion 21a so as to extend horizontally. With the crush box 17 inserted between the two mounting wall portions 21b, 2 lb of the mounting wall portion is welded to the crush box 17, so that the lid body 21 force S is fixed to the crush box 17. The lid body 21 is provided with a plurality of weld nuts 22 welded to the rear surface (inner side surface) of the blocking wall portion 21a.

[0026] Each of the crash boxes 17 is configured such that the front surface (outer surface) of the lid body 21, more specifically, the front surface (outer surface) of the blocking wall portion 2la abuts the rear surface (inner surface) of the main wall portion 16a. And sandwiched between the pair of opposing wall portions 16b and 16c. Therefore, the front end of the crash box 17 is covered with the lid body 21 and the main wall portion 16a. Fastening bolts 23 that pass through the main wall portion 16a and the blocking wall portion 21a from the front of the vehicle are screwed into the weld nuts 22 and tightened to fix the bumper-in hose 16 to the crash box 17. ing.

A bracket 18 is fixed to the rear end of each crash box 17 by welding.

On the other hand, each of the side members 12 has a rectangular tube shape and extends so that its axis substantially coincides with the axis of the corresponding crash bot 17. A bracket 19 facing the bracket 18 of the crash box 17 is provided at the front end of each side member 12. A plurality of weld nuts 24 are welded to the rear surface of the bracket 19. Fastening bolts 25 penetrating the brackets 18 and 19 from the front of the vehicle are screwed into the weld nuts 24 and tightened, whereby each crash box 17 is fixed to the corresponding side member 12. The bumper frame 11 is fixed to the vehicle body by fastening the bracket 18 of the crash box 17 and the bracket 19 of the side member 12 to each other.

[0028] For example, when an impact along the longitudinal direction of the vehicle is applied to the bumper inhose 16 due to a vehicle collision, the impact force in the longitudinal direction of the vehicle immediately after the plate-like bumper inhose 16 is slightly bent. It is transmitted to the crash box 17 as (axial compression load). In other words, in this embodiment, after the bumper rein hose 16 is bent, the The axial compressive load acting on the shbox 17 rises.

More specifically, FIG. 3 (a) shows the relationship between the load (bending load) acting on the bumper rein hose 16 and the stroke (deformation amount) of the bumper rein hose 16, and FIG. 3 (b) Indicates the relationship between the load acting on the crash box 17 (axial compression load) and the stroke of the crash box 17 (deformation amount). Fig. 3 (a) shows the characteristics of the bumper inn hose 16 alone, and Fig. 3 (b) shows the characteristics of the crash box 17 alone. On the other hand, FIG. 3 (c) shows the relationship between the load acting on the bumper including the bumper rein hose 16 and the crash box 17 and the stroke (deformation amount) of the bumper.

[0030] As shown in Fig. 3 (a), the plate-like bumper rein hose 16 has a crush box 17 force S compared to the load required to start buckling deformation (buckling start load) F2. It bends and buckles with a sufficiently small load F1. On the other hand, as shown in FIG. 3 (b), the crash bot 17 starts buckling deformation when the axial compressive load acting on the crash box 17 reaches the buckling start load F2, and then the bellows-like shape. Repeated buckling deformation continuously. The axial compressive load when the crash box 17 repeats buckling deformation changes at a sufficiently large value as compared with the load F1 required for plastic deformation of the bumper inhose 16.

Therefore, as shown by the solid line in FIG. 3 (c), the entire bumper including the bumper rein hose 16 and the crash bots 17 has a load acting on the pampa so that the plastic force in the bumper rein hose 16 is reduced. The deformation (see the two-dot chain line in FIG. 3 (c)) can be substantially ignored, and quickly rises up to the buckling start load F2. Therefore, the crash box 17 starts buckling deformation immediately after the vehicle collision. This becomes clearer by comparing the characteristics of the present embodiment shown by the solid line in Fig. 3 (c) with the characteristics of the conventional example shown by the broken line (see Fig. 6 (c)). .

[0032] After the buckling deformation starts, the crash box 17 repeats the buckling deformation in the axial direction, thereby quickly absorbing the impact energy accompanying the vehicle collision. Therefore, the impact due to the vehicle collision is transmitted to the vehicle body and the occupant after being reduced by the bumper.

As described in detail above, this embodiment has the following advantages.

(1) In the present embodiment, in the event of a vehicle collision, the axial compression load acting on the crash box 17 rises immediately after the bumper-in hose 16 is bent. This allows you to The shbox 17 can quickly plastically deform in the axial direction (front-rear direction of the vehicle) by the transmitted load, and can efficiently absorb the impact energy accompanying the vehicle collision.

In order to increase the impact energy absorption capability of the crash box 17, it is desirable that the crash box 17 is longer. However, the increase in the length of the crash box 17 increases the mounting space of the pump for the vehicle. In this regard, in the present embodiment, the crash box 17 is fixed to the bumper hose 16 while being sandwiched between the pair of opposed wall portions 16b and 16c. Therefore, the length of the crash box 17 in the front-rear direction of the vehicle can be increased by the amount that the crash box 17 is inserted into the vannori hose 16 without increasing the mounting space of the bamba with respect to the vehicle.

[0036] Further, the bumper reinhose 16 has a second moment of inertia increased by a pair of opposing wall portions 16b and 16c bent with respect to the main wall portion 16a. In addition, the sectional moment of the bumper inhose 16 is further increased by the flange wall portions 16d and 16e bent with respect to the opposing wall portions 16b and 16c. In such a configuration, for example, due to an offset collision with another vehicle or the like, only one crash box 17 fixed to one end of the bumper inhose 16 can exert a force (axial compressive load) in the longitudinal direction of the vehicle. Assume that significant plastic deformation occurs. In this case, the crash box 17 on the anti-collision side fixed to the other end of the bumper-in hose 16 is pulled through the bumper-in hose 16. However, the increased moment of inertia of the bumper reinhose 16 prevents the load that tries to collapse the crash box 17 on the anti-collision side from acting on the crash box 17. The crash box 17 on the anti-collision side is pulled in the axial direction. Therefore, it is possible to suppress breakage of the joint between the crash box 17 on the anti-collision side and the bumper in-hose 16 and the joint between the crash box 17 on the anti-collision side and the side member 12 described above. That is, it is possible to prevent the crash box 17 on the anti-collision side from coming off the bumper inhose 16 or the vehicle body force due to the offset collision.

[0037] (2) In this embodiment, all the weld nuts 22 and the fastening bolts 23 that fasten the main wall portion 16a and the lid 21 to each other have axes extending in a direction perpendicular to the main wall portion 16a. Have. Therefore, all the fastening bolts 23 are aligned with the corresponding weld nuts along the same direction. Since the bumper in-hose 16 and the crash box 17 can be fixed smoothly.

[0038] The above embodiment may be modified as follows.

As shown in FIG. 4, the lid 21 may be omitted, and weld nuts 31 may be welded to the inner side surfaces of the tip end portions of the upper wall portion 17a and the lower wall portion 17b of the crash box 17, respectively. Then, the fastening bolt 32 penetrating the upper opposing wall portion 16b and the upper wall portion 17a from above is screwed and tightened to the corresponding wall nut 31, and the lower opposing wall portion 16c and lower wall are tightened. The fastening bolt 33 that penetrates the portion 17b from below is screwed into the corresponding weld nut 31 and tightened, so that the bumper-in hose 16 and the crash box 17 can be fixed to each other. . In this case, the bumper-in hose 16 is directly fixed to the crash box 17 without any other parts such as the lid 21 (mounting tool), so that the number of parts can be reduced by lj.

Further, as shown in FIG. 5, the corner portion between the upper facing wall portion 16b and the flange wall portion 16d is welded to the upper wall portion 17a, and the lower facing wall portion 16c and the flange are welded. The corner portion between the wall portion 16e and the lower wall portion 17b may be welded so that the bumper inhose 16 and the crash box 17 are fixed to each other. In addition, the symbol W shown in FIG. Even in this case, the bumper inhose 16 is directly fixed to the crash box 17 without using another part such as the lid 21 (mounting tool), so that the number of parts can be reduced.

[0041] The cross-sectional shape of the illustrated bumper-in hose 16 is an example, and may be changed as appropriate. For example, the flange wall portions 16d and 16e may be omitted if a sufficient moment of inertia of the cross section is secured. Alternatively, if the bumper rein hose 16 and the crash box 17 (or lid 21) do not interfere with each other, ribs extending along the longitudinal direction of the main wall portion 16a that increases the moment of inertia of the cross section. (Concave or convex) may be formed.

[0042] The cross-sectional shape of the illustrated crash box 17 is an example, and may be changed as appropriate.

For example, a crush box having a cross-shaped partition wall inside a hollow cylinder having a square cross section, a flat plate partition wall, or two or more flat partition walls parallel to each other may be adopted. Good.

[0043] The bumper-in hose 16 or the crash box 17 may be formed of an aluminum alloy material. In this case, the bumper-in hose 16 or the crush box 17 may be manufactured by extrusion molding. Further, the bumper-in hose 16 or the crash box 17 may be formed of other materials such as a magnesium alloy material.

[0044] The coupling mode of the crash box 17 and the side member 12 shown in the figure is an example, and can be changed as appropriate.

[0045] The present invention may be applied not only to a pumper at a front portion of a vehicle but also to a pumper at a rear portion of a vehicle. In this case, the pair of opposing wall portions 16b and 16c are bent with respect to the main wall portion 16a so as to extend from the upper end and the lower end of the main wall portion 16a toward the front of the vehicle.

Claims

The scope of the claims

[1] A bumper comprising a bumper inhose extending in a width direction of the vehicle and a pair of hollow crush boxes fixed to both ends of the bumper inn hose and extending in the front-rear direction of the vehicle.

The bumper-in hose has a plate shape, and is bent with respect to the main wall portion so as to extend from the upper and lower ends of the main wall portion toward the front or rear of the vehicle, respectively. A pair of opposed wall portions,

The bumper is characterized in that the tip of each crash box is covered with the main wall portion and is fixed to the bumper inn hose while being sandwiched between the pair of opposing wall portions.

[2] In the Pampa according to claim 1,

The bumper-in hose has a flange wall portion bent with respect to a corresponding opposing wall portion so as to extend in directions opposite to each other from the ends of the pair of opposing wall portions. Characteristic Pampa.

[3] In the Pampa according to claim 2,

Each of the crush boxes has an upper wall portion and a lower wall portion facing each other, and a corner portion between the pair of opposing wall portions and the flange wall portion corresponding thereto corresponds to the upper wall portion and the lower wall, respectively. Bamba characterized by being welded to the part.

[4] In the Pampa according to claim 1 or 2,

Each crash box has an opening at its tip, and a lid is fixed to each crash box so as to close the opening,

The bumper, wherein the main wall portion is fastened to the lid using bolts and nuts, whereby the bumper-in hose is fixed to each of the crash boxes.

[5] In the Pampa according to claim 1 or 2,

Each of the crash boxes has an upper wall portion and a lower wall portion facing each other, and the pair of opposing wall portions are fastened to the upper wall portion and the lower wall portion using bolts and nuts, respectively. Pampa.

[6] Both ends of the bumper inhose extending in the width direction of the vehicle and extending in the front-rear direction of the vehicle In a shock absorbing structure for a vehicle in which a pair of hollow crush boxes are arranged between a pair of side members,

The front end of each crash box is covered with the main wall portion and is fixed to the bumper inn hose while being sandwiched between the pair of opposing wall portions. Construction.