JP2009056857A - Bumper device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bumper device for a vehicle enabling the overall length of the vehicle to be shortened while properly absorbing, for example, the impact energy of the vehicle at the time of a collision. <P>SOLUTION: This bumber device for the vehicle comprises a pair of first crush boxes 13 interposed between a first bumber reinforcement 17 extending in the lateral direction of the vehicle and a pair of side members 11 extending in the longitudinal direction of the vehicle, respectively, at both ends of the first bumber reinforcement, a pair of second crush boxes 21 interposed between a second bumber reinforcement 23 and radiator support sides 12 joined to ends of a pair of side members 11, respectively, at both ends of the second bumber reinforcement 23, and suspension members 26 each disposed on the rear side more than the base end of each second crush box 21 and elastically deforming an elastic deformation part bent in the axial direction of the second crush box 21 in a bellows shape by coming into contact therewith. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle bumper device.

  Conventionally, as a bumper device for vehicles, what was indicated, for example in patent documents 1 is known. In this vehicle bumper device, a pair of front side members (12) extending in the front-rear direction of the vehicle are attached to both ends of a bumper inhose (14) extending in the width direction of the vehicle. These front side members are fitted with a front-view-type front subframe (22) and a pair of crash boxes (34) extending in the front-rear direction of the vehicle at the front end of the front subframe. Furthermore, a sub-cross (48) extending in the width direction of the vehicle is attached to the front ends of these crash boxes.

In such a configuration, for example, at the time of a vehicle collision, the front side member or the crash box is plastically deformed in a bellows shape to absorb the impact energy at that time, thereby reducing the amount of deformation of the vehicle and ensuring passenger protection.
Japanese Patent Laying-Open No. 2005-81955 (FIGS. 1 and 6)

  By the way, in this vehicular bumper device, when the crash box is deformed bellows, a crushing residue is generated on the front side of the front subframe. FIG. 7 shows the transition of plastic deformation at the time of a vehicle collision of the crash box 91 schematically shown together with the relationship between the deformation amount and the load at that time. As shown in the figure, in the crash box 91 that deforms bellows, a crushing residue is generated on the front side of the front subframe (indicated by the straight line V). In other words, the length of the crash box 91 needs to be long enough to allow for the remaining collapse. Accordingly, the length of the crash box 91 and the length of the vehicle are increased and the mass is increased.

  An object of the present invention is to provide a vehicle bumper device that can further reduce the overall length of the vehicle while suitably absorbing impact energy at the time of a vehicle collision, for example.

  In order to solve the above problem, the invention according to claim 1 is a pair of first bumper in hoses extending in the front-rear direction of the vehicle at both ends of the first bumper in hoses extending in the width direction of the vehicle. A pair of first crash boxes that are respectively interposed between the side members of the vehicle and absorb the applied load by plastic deformation in the axial direction to absorb impact energy, and a second bumper inhose extending in the width direction of the vehicle At both ends, the second bumper-in hose and the support member coupled to the ends of the pair of side members are respectively interposed, and the applied load is absorbed by plastic deformation in a manner of folding back in the axial direction. A pair of second crash boxes that absorb impact energy, and are arranged on the vehicle front-rear direction inner side than the base ends of the second crash boxes. And summarized in that and a regulating member to further plastically deformed like bellows the 該塑 deformation portion in contact with the plastically deformed portion which is folded back axially person.

  According to this configuration, for example, in the event of a vehicle collision, the second crush box is plastically deformed in a manner that it is folded back in the axial direction, so that the crushing residue on the outer side in the vehicle front-rear direction of the support member can be finally eliminated. it can. Accordingly, since it is not necessary to allow for the remaining crushing length in the length of the second crash box, the length of the second crash box can be further shortened, and consequently the overall length of the vehicle can be shortened. Further, the second crash box can absorb a larger impact energy by the plastic deformation portion folded back in the axial direction coming into contact with the regulating member and further plastically deforming in a bellows shape.

  According to a second aspect of the present invention, in the vehicular bumper device according to the first aspect, the restriction member has a length (L / 2) that is half the length of the second crash box in the vehicle front-rear direction. The gist is that the second crash box is spaced apart from the proximal end of the second crash box inward in the vehicle longitudinal direction.

  According to this configuration, when the plastic deformation portion reaches a length (L / 2) that is half the length (L) of the second crash box in the vehicle front-rear direction, that is, the second crash box is the vehicle. When completely folded back in the front-rear direction, it comes into contact with the restriction member. Accordingly, the second crash box, for example, continuously absorbs the impact energy by completing the plastic deformation of the aspect that is folded back in the axial direction at the time of a vehicle collision, and at the same time the plastic deformation portion starts the plastic deformation in a bellows shape. be able to.

  According to a third aspect of the present invention, in the vehicle bumper device according to the first or second aspect, the regulation member is provided with a guide portion that guides the bellows-like plastic deformation of the plastic deformation portion. Is the gist.

  According to this configuration, the restriction member is provided with the guide portion that guides the bellows-like plastic deformation of the plastic deformation portion, so that, for example, the plastic deformation portion falls down without plastic deformation. Can be suppressed.

The gist of the invention according to claim 4 is the vehicle bumper device according to any one of claims 1 to 3, wherein the regulating member is coupled to the side member.
According to this configuration, since it is not necessary to separately provide a dedicated member for supporting the restriction member, it is possible to suppress an increase in the number of parts.

The gist of the invention according to claim 5 is the vehicle bumper device according to any one of claims 1 to 4, wherein the regulating member is a suspension member.
According to this configuration, the restriction member is an existing suspension member for supporting a suspension, an engine, and the like, so that an increase in the number of parts can be suppressed.

  In the present invention, for example, it is possible to provide a vehicular bumper device capable of further reducing the overall length of the vehicle while suitably absorbing impact energy at the time of a vehicle collision.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1 and FIG. 2 are a perspective view and a longitudinal sectional view showing a vehicle bumper device according to this embodiment applied to a front portion of a vehicle such as an automobile. In FIG. 1, for convenience, the structure on one side in the width direction of the vehicle (right side toward the front of the vehicle) is partially omitted. As shown in the figure, this vehicular bumper device is attached to a pair of side members 11 that are disposed on both sides in the width direction of the vehicle and constitute a part of the body. Each side member 11 is made of, for example, a metal plate, has a hollow structure with a substantially square cross section, and extends in the front-rear direction of the vehicle.

  A radiator support side 12 as a supporting member made of, for example, a metal plate is fixed to the front end of each side member 11 by welding in a manner that closes the opening of the side member 11. The pair of radiator support sides 12 together with a radiator support upper (not shown) that bridges between both upper ends and a radiator support lower (not shown) that bridges between both lower ends constitute a radiator support that supports the radiator.

  A first crash box 13 made of, for example, a metal plate and having a hollow structure with a substantially square cross section and extending in the front-rear direction of the vehicle is attached to the front surface of each radiator support side 12. The first crush box 13 is disposed such that the center line in the front-rear direction coincides with the center line in the front-rear direction of the side member 11, and the radiator support is provided in a bracket 14 fixed to the rear end thereof by welding. The side 12 is fastened with bolts 15 and nuts. The pair of first crush boxes 13 absorb the applied energy by absorbing the applied load by plastic deformation in the axial direction. Each first crush box 13 is plastically deformed in a bellows shape in the axial direction.

  A plate 16 made of, for example, a metal plate is fixed to the front end of each first crash box 13 by welding in a manner that closes the opening of the first crash box 13. Each end portion of the first bumper-in hose 17 extending in the width direction is fastened with a bolt 18 and a nut. The first bumper-in hose 17 has a constant cross section having a substantially square cross section made of, for example, an aluminum extruded material, and the pair of first crash boxes in the above-described manner at both ends in the width direction of the vehicle. 13 is supported.

  Each radiator support side 12 has a circular through hole 12a penetrating in the front-rear direction on the lower side of the bracket 14, and the radiator support side 12 has an outer diameter smaller than the inner diameter of the through hole 12a. A lidded cylindrical second crush box 21 having a diameter and disposed along the center line of the through hole 12a is attached. The second crush box 21 is formed by, for example, deep drawing of a metal plate (steel plate), and the base end portion thereof is folded back to the front end side over the entire circumference to form an annular circumferential groove 21a. In addition, the outer flange 21b is formed by being bent radially outward from the tip of the circumferential groove 21a. The second crash box 21 located below the first crash box 13 is fastened to the radiator support side 12 with bolts 22 and nuts at an outer flange 21b. The second crush box 21 is arranged so that the center line in the front-rear direction coincides with the center line in the front-rear direction of the first crush box 13 (and the side member 11) in plan view. The pair of second crash boxes 21 absorb the applied energy by absorbing the applied load by plastic deformation in the axial direction.

  Each of the second crash boxes 21 is plastically deformed (so-called turning deformation) in a manner of being folded back in the axial direction, and a space S that allows folding back in the axial direction is provided behind the second crash box 21. Exists. The second crush box 21 may continue to absorb the impact energy until there is no crushed residue at least on the front side of the coupling portion (radiator support side 12) by turning deformation so as to fit in the space S. Yes (see FIG. 3). Alternatively, the second crash box 21 can continue to absorb the impact energy until the second bumper-in hose 23 comes into contact with the radiator support side 12. Further, the circumferential groove 21 a formed at the base end portion of each second crash box 21 forms a stress concentration portion that is a starting point of turning deformation of the second crash box 21.

  At the front end of each second crash box 21, each end portion of a second bumper inhose 23 extending in the vehicle width direction is fastened with a bolt 24 and a nut. The second bumper-in hose 23 has a constant cross section made of, for example, an aluminum extruded material and has a substantially rectangular cross section. It is supported. Note that the position of the front end face of the second bumper rein hose 23 is set to substantially coincide with the position of the front end face of the first bumper rein hose 17 in the vehicle longitudinal direction. Therefore, for example, at the time of a vehicle collision, an impact from the front is basically applied to the first and second bumper in hoses 17 and 23 simultaneously.

  A metal suspension member 26 as a regulating member is fastened to the lower surface (end portion) of the side member 11 with bolts 27 and nuts. The suspension member 26 is for mounting a front suspension, an engine, or the like, for example, and constitutes a part of the body. The suspension member 26 has a front end surface that is half the length (L / 2) of the second crash box 21 in the vehicle front-rear direction (L / 2) from the base end of the second crash box 21. It arrange | positions so that it may space apart in the vehicle front-back direction inner side (rear side).

  Here, when an impact is applied from the front due to a vehicle collision or the like, the impact is transmitted to the side member 11 (body) via the first bumper-in hose 17 and the first crash box 13, and the second It is transmitted to the side member 11 that supports the radiator support side 12 via the bumper-in hose 23 and the second crash box 21. At this time, the first and second crush boxes 13 and 21 together with the first and second bumper in hoses 17 and 23 are plastically deformed, so that the shock transmitted to the body is buffered.

  At this time, as shown in FIGS. 3A, 3 </ b> B, and 3 </ b> C, the second crash box 21 is plastically deformed so as to be folded back in the axial direction, so that the vehicle of the radiator support side 12 is finally obtained. There can be no crushing residue on the outside in the front-rear direction (front side). At this time, the second crush box 21 is completely folded back in the vehicle front-rear direction inside (rear side), and the plastic deformation portion 30 having a substantially double round cross section folded back in the axial direction has the length (L / 2) described above. , The suspension member 26 comes into contact. Then, the plastic deformation portion 30 in contact with the suspension member 26 is further plastically deformed in a bellows shape. In addition, the bellows-like plastic deformation indicates one mountain fold in the present embodiment. When the impact energy accompanying the plastic deformation of the plastic deformation portion 30 is absorbed, the side member 11 is also plastically deformed in a bellows shape to absorb the impact energy.

Thus, the impact energy applied to the body and the occupant is absorbed.
FIG. 4 is a graph showing the relationship between the amount of deformation and the load in the second crush box 21 alone when absorbing the impact energy. As shown in the figure, before the plastic deformation, the second crush box 21 absorbs the impact energy in a state where the load is stabilized by being deformed by turning. On the other hand, in the latter stage of plastic deformation where the deformation amount exceeds the length (L), the second crush box 21 (plastic deformation portion 30) deforms bellows and further absorbs impact energy. In the figure, for the sake of convenience, the transition of a conventional crash box that is only plastically deformed in a bellows shape is also drawn with a broken line.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) In the present embodiment, for example, in the event of a vehicle collision, the second crash box 21 is deformed in a turning manner so as to be accommodated in the existing space S. The shock energy can continue to be absorbed until there is no remaining crush on the (front side). Accordingly, since it is not necessary to allow for the remaining crushing length in the length of the second crash box 21, the length of the second crash box 21 can be further shortened, and consequently the overall length of the vehicle can be shortened. In addition, it has been confirmed that approximately 30% of the total length (length in the front-rear direction) of the crush box that plastically deforms in a bellows shape is generated as an uncrushed portion. That is, if the impact energy absorption amount of the crash box is equal, the space can be saved by approximately 30% of the total length. Further, the second crash box 21 can absorb a larger impact energy by the plastic deformation portion 30 folded back in the axial direction coming into contact with the suspension member 26 and further plastically deforming in a bellows-like manner. A vehicle having a reduced amount of deformation and excellent safety can be realized.

  (2) In the present embodiment, when the plastic deformation portion 30 reaches a length (L / 2) that is half the length (L) of the second crash box 21 in the vehicle front-rear direction, that is, the second When the crash box 21 is completely folded back in the vehicle longitudinal direction inner side (rear side), it comes into contact with the suspension member 26. Accordingly, the second crash box 21 can absorb impact energy continuously, for example, when the turning deformation is completed at the time of a vehicle collision, and at the same time, the plastic deformation portion 30 starts plastic deformation in a bellows shape.

  (3) In this embodiment, since the suspension member 26 is coupled to the side member 11, it is not necessary to separately provide a dedicated member for supporting the suspension member 26, and the number of parts can be increased. Can be suppressed.

  (4) In the present embodiment, the second crash box 21 is coupled by the existing radiator support for supporting the radiator, so that the increase in the number of parts can be suppressed, and the cost can be reduced. be able to.

  (5) In the present embodiment, by performing the bellows deformation of the second crash box 21 with the existing suspension member 26 for supporting the suspension, the engine, etc., an increase in the number of parts can be suppressed, and consequently Cost can be reduced.

(6) In the present embodiment, the second crash box 21 can be further deformed by turning to further stabilize the load when absorbing the impact energy.
(7) In the present embodiment, the second crush box 21 is further bellows deformed after the turning deformation and absorbs a larger impact energy, for example, the longitudinal length of the first and second crush boxes 13, 21. The vehicle can be realized with a shorter design and an overhang (distance from the center of the front wheel to the front end of the bumper) with a shorter design.

  (8) In this embodiment, the impact energy is absorbed in a wider range by the first and second bumper-in hoses 17, 23, etc., thereby reducing the load per unit area applied to the opponent vehicle at the time of collision between vehicles, for example. It is possible to suppress the harmfulness of the host vehicle.

In addition, you may change the said embodiment as follows.
As shown in FIG. 5, an annular guide portion 36 protruding from the front end surface of the suspension member 26 having a center line that coincides with the center line of the second crash box 21 may be provided. . The guide portion 36 has an inner diameter equivalent to the outer diameter of the circumferential groove 21a, and guides the bellows deformation of the plastic deformation portion 30 that contacts the suspension member 26. Thereby, for example, it can suppress that the plastic deformation part 30 falls sideways without plastically deforming.

  -As shown in FIG. 6, you may employ | adopt the cylindrical 2nd crush box 37 with a covered step. In this case, the annular step 37 a that expands the second crash box 37 forms a stress concentration portion that becomes a starting point of turning deformation of the second crash box 37.

  In the embodiment, the front end surface of the suspension member 26 is spaced apart from the base end portion of the second crash box 21 in the vehicle longitudinal direction (rear side) by a distance longer than the length (L / 2). May be. In this case, the second crush box 21 waits for a predetermined time after the turning deformation is completed, for example, at the time of a vehicle collision, and then the plastic deformation portion 30 starts plastic deformation in a bellows shape.

  -In the said embodiment, the absorption start timing of the impact energy by the 1st and 2nd bumper in hoses 17 and 23 (the 1st and 2nd crash boxes 13 and 21) is delayed to some extent from either one to the other. It may be.

  In the above embodiment, a blind nut may be adopted instead of any of the bolts 15, 18, 22, 24, 27 and the nuts combined with the bolts for fastening each member. In this case, unlike the combination of the bolt and the nut, it is not necessary to set the mounting direction in two directions, and the mounting direction may be only one direction, so that the mounting performance can be improved.

  In the above embodiment, the radiator support side 12 and the first crash box 13 or the first crash box 13 and the first bumper-in hose 17 may be joined by welding. Further, the radiator support side 12 and the second crash box 21, or the second crash box 21 and the second bumper-in hose 23 may be joined by welding. Further, the side member 11 and the suspension member 26 may be joined by welding.

-In the said embodiment, the cross-sectional shape of the 1st bumper-in hose 17 may be a character of a mouth, a character of a day, or a rice field.
-In the said embodiment, the cross-sectional shape of the 2nd bumper-in-hose 23 may be a Japanese character, an eye character, or a rice field.

In the embodiment, the first and second bumper in hoses 17 and 23 may be formed of a metal plate.
-In the said embodiment, the cross-sectional shape of the 1st crush box 13 may be a Japanese character, an eye character, or a rice field.

In the embodiment, the first crush box 13 may be formed of an aluminum extruded material.
In the above-described embodiment, the suspension member 26 may not be directly connected to the side member 11, and may be substantially integrated with the side member 11 via an appropriate intermediate member.

The perspective view which shows one Embodiment of this invention. The longitudinal cross-sectional view which shows the same embodiment. (A) (b) (c) is a schematic diagram which shows operation | movement of the embodiment. The graph which shows the relationship between the deformation of the same embodiment, and a load. The perspective view which shows the deformation | transformation form of this invention. The longitudinal cross-sectional view which shows the deformation | transformation form of this invention. Explanatory drawing which shows the relationship between the deformation of a prior art example, and a load.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Side member, 12 ... Radiator support side (support member), 13 ... 1st crash box, 17 ... 1st bumper inhose, 21, 37 ... 2nd crash box, 23 ... 2nd bumper inn hose, 26 ... suspension member (regulating member), 30 ... plastic deformation part, 36 ... guide part.

Claims (5)

The both ends of the first bumper inhose extending in the vehicle width direction are respectively interposed between the first bumper inhose and the pair of side members extending in the front-rear direction of the vehicle. A pair of first crash boxes that absorb the impact energy by absorbing the plastic deformation of
At both ends of the second bumper inhose extending in the width direction of the vehicle, the second bumper inhose is interposed between and added to the support members coupled to the ends of the pair of side members, respectively. A pair of second crush boxes for absorbing impact energy by absorbing the load by plastic deformation in a manner of turning back the load in the axial direction;
A regulation that is arranged on the inner side in the vehicle longitudinal direction from the base end of each second crash box and abuts against the plastic deformation portion folded back in the axial direction of the second crash box to further plastically deform the plastic deformation portion into a bellows shape. And a bumper device for a vehicle. The vehicle bumper device according to claim 1,
The restricting member is spaced apart from the base end of the second crash box by the length (L / 2) half of the length (L) of the second crash box in the vehicle longitudinal direction. A bumper device for a vehicle. The vehicle bumper device according to claim 1 or 2,
A bumper device for vehicles, wherein the restricting member is provided with a guide portion for guiding the bellows-like plastic deformation of the plastic deformation portion. In the bumper device for vehicles according to any one of claims 1 to 3,
The vehicle bumper device, wherein the restricting member is coupled to the side member. In the vehicle bumper device according to any one of claims 1 to 4,
The bumper device for vehicles, wherein the restricting member is a suspension member.

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