JP2011051508A - Shock absorbing material of shock absorbing bumper for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shock absorbing material of a shock absorbing bumper for a vehicle excellent in absorbing impact energy, being light weight, and reduced in manufacturing cost. <P>SOLUTION: A shock absorbing material 10 provided between a bumper beam 2 and a bumper face 7 includes: a front shock absorbing part 11 having a top surface 12, a front upper surface 13, and a front lower surface 14; and a rear shock absorbing part 21 having a rear upper face 22 arranged continuously to the rear end of the front upper surface 13 and a rear lower surface 25 arranged continuously to the rear end of the front lower surface 14. An upper flange 24 abutting on a front surface 3 of the bumper beam 2 is provided on the rear end edge 22b of the rear upper surface 22, and a lower flange 27 abutting on the front surface 3 of the bumper beam 2 is provided on the rear end edge 25b of the rear lower surface 25. A plurality of upper beads 23 are provided on the rear upper surface 22, and a plurality of lower beads 26 are provided on the rear lower surface 25. In an early stage when a shock load is applied to the top surface 12, the shock absorbing material 10 is crushed and deformed without the rapid generation of an initial resistant force. Thus, a large deformation stroke is obtained. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a shock absorbing material for a shock absorbing bumper for a vehicle, and more particularly, a resin shock absorbing material that is disposed extending in the vehicle width direction between a front surface of a bumper beam extending in the vehicle width direction and a bumper face. About.

  The shock absorbing bumper for a vehicle plays a role of mitigating the impact and preventing the vehicle body from being damaged when the vehicle comes into contact with an external object or a pedestrian. On the other hand, bumpers with an emphasis on pedestrian protection have been developed in recent years, and bumpers are required to suppress damage to pedestrians as much as possible. In other words, the shock absorbing bumper is required to have a shock energy absorption property that does not cause damage to the pedestrian's leg so that it cannot be recovered even when it comes into contact with the pedestrian at a relatively high speed. Is done.

  This type of shock absorbing bumper includes, for example, a bumper beam 101 that is disposed at the front of the vehicle body and extends in the vehicle width direction as shown in a cross section in FIG. 12, and a vehicle width along the front surface 101a of the bumper beam 101. A shock absorber 102 arranged in the direction and a bumper face 103 covering the shock absorber 102 are formed as main parts. The shock absorbing material 102 is formed of a foamed resin such as polypropylene, and the bumper face 103 is formed of a resin such as polyurethane or polypropylene.

  Here, the deformation resistance against the impact of the shock absorbing material 102 made of foamed resin such as polypropylene is almost determined by the foaming ratio of the foamed resin and the deformation stroke amount of the shock absorbing material 102, especially when the foaming ratio of the foamed resin is low. The initial drag tends to rise rapidly and become excessive. In addition, it is difficult to set the deformation resistance in the intermediate region of the deformation process of the shock absorber 102, that is, to adjust the energy absorbability, the desired shock energy absorbability cannot be achieved, and the pedestrian's legs are sufficiently protected. I am concerned that I cannot do it. An example of the correlation between the deformation resistance and the deformation stroke by the shock absorbing material 102 made of the foamed resin is shown by a broken line “a” in the “FS (load-deformation stroke) correlation diagram” shown in FIG.

  A bumper disclosed in Patent Document 1 is known as a measure for suppressing the rapid rising of the initial drag. In the bumper of Patent Document 1, as shown in a cross-sectional view in FIG. 13, an impact absorbing material 112 formed of foamed resin is disposed between a bumper beam 111 and a bumper face 113 extending in the vehicle width. In the bumper, a plurality of groove-like recesses 112a and protrusions 112b that are continuous in the vehicle width direction are alternately formed on the rear surface of the shock absorber 112 that contacts the front surface 111a of the bumper beam 111 so as to contact an object or a pedestrian's leg. When this occurs, the projecting portion 112b is subjected to compression deformation or buckling deformation by the impact load to suppress a sudden rise and increase in initial drag.

  Further, in Patent Document 2, an impact absorbing material such as a metal pipe formed by connecting a small diameter pipe portion and a large diameter pipe portion through a step is disposed between the bumper and the vehicle body, and the bumper receives an impact. There is disclosed an impact absorbing device for a vehicle that absorbs impact energy by a squeezing of a step in a deformation process in which a small diameter pipe part is pushed into a large diameter pipe part when received.

JP 2004-82957 A JP 2003-160011 A

  According to Patent Document 1, even when the foaming resin forming the shock absorbing material 112 has a relatively low expansion ratio, the front surface 111a of the bumper beam 111 is caused by the impact load when it comes into contact with an object or a leg of a pedestrian. By compressing and deforming the projecting portion 112b of the shock absorbing material 112 in contact with the base material, a sudden rise and increase in initial drag can be suppressed to some extent.

  However, since the protruding portion 112b is formed in a thin shape that continues in the vehicle width direction, a sudden seating as shown by the phantom line in the process in which the protruding portion 112b compresses and deforms due to an impact load caused by contact with an object or a pedestrian. There is concern about the occurrence of bending deformation. If a sudden buckling deformation occurs in the projecting portion 112b in the process of compressive deformation, the deformation drag will drop rapidly and the desired impact energy absorption will not be obtained, and the object and the leg of the pedestrian can be sufficiently protected. There is a concern that it will induce damage. The correlation between the deformation drag accompanied by this sudden buckling deformation and the deformation stroke is shown by a dashed line b in the “FS (load-deformation stroke) correlation diagram” shown in FIG. In addition, it is difficult to set the deformation resistance in the intermediate region of the deformation process, and there is a possibility that a desired required impact energy absorbability cannot be achieved. In addition, the impact absorbing member made of foamed resin is relatively heavy, and there is a concern about an increase in manufacturing cost of the impact absorbing material by foam molding.

  According to Patent Document 2, the shock absorber is constituted by a small diameter pipe portion and a large diameter pipe portion connected through a step, and the impact energy is absorbed in a deformation process in which the small diameter pipe portion is pushed into the large diameter pipe portion. Therefore, the initial drag suddenly rises and becomes excessive, and it is difficult to set the deformation drag in the intermediate region of the deformation process, so that the desired required shock energy absorption cannot be achieved, and the pedestrian's legs may not be sufficiently protected. is there. In addition, the impact absorbing material made of a metal pipe is relatively heavy and is difficult to form, and there is a concern about an increase in manufacturing cost.

  Accordingly, an object of the present invention made in view of such a point is to provide an impact absorbing material for an impact absorbing bumper for a vehicle that is excellent in impact energy absorption and is lightweight and capable of reducing the manufacturing cost.

  The shock absorbing material for a vehicle shock absorbing bumper according to claim 1, which achieves the above object, is disposed so as to extend in the vehicle width direction between a front surface of the bumper beam extending in the vehicle width direction and the bumper face. A shock absorber for a resin vehicle shock absorbing bumper has a top surface extending in the vehicle width direction and a front upper surface and a front lower surface that are curved and continuous from the upper edge and the lower edge of the top surface, respectively. A front impact absorbing portion having a substantially U-shaped cross section and continuing in the vehicle width direction, and a contact portion where the front end edge is continuous with the rear end of the front upper surface and the front end of the bumper beam contacts the rear end edge are formed. A rear shock absorber having a rear upper surface and a rear lower surface facing the rear upper surface and having a front end edge continuous with the rear end of the front lower surface and a contact portion contacting the front surface of the bumper beam at the rear end edge; The resistance against impact load input from the front is Characterized in that the rear shock absorber from part impact absorbing portion is larger.

  As a result, in the initial stage where an impact load is applied to the top surface, the front upper surface and the front lower surface of the front shock absorbing portion are gently crushed and deformed, and the initial drag is not rapidly increased, and further the front shock absorption is achieved. In the intermediate stage of the deformation process after the deformation of the part, the rear upper surface and the rear lower surface of the rear shock absorbing part are gently crushed and deformed by the load input through the crushing deformed front shock absorbing part, resulting in a sudden deformation drag Is suppressed, an increase in deformation stroke is obtained, and good impact energy absorption is ensured. Therefore, even if it is a case where it contacts with a pedestrian, the damage to a pedestrian's leg part can be reduced very much.

  In addition, the shock absorber is made of a resin having a substantially U-shape and a hollow cross-sectional shape that is continuous in the vehicle width direction, and can be made relatively lightweight, resulting in a lightweight bumper and excellent productivity and injection molding and compressed air pressure. Molding by molding or the like is easy and a reduction in manufacturing cost can be expected.

  According to a second aspect of the present invention, in the shock absorber for the shock absorbing bumper for a vehicle according to the first aspect, the rear upper surface is open at a lower portion continuous in the front-rear direction from the front edge of the rear upper surface to the contact portion. A corrugated plate shape in which a plurality of upper beads having a U-shaped section or a C-shaped section protruding upward are continuously formed in the vehicle width direction, and the rear lower surface is a contact portion from the front edge of the rear lower surface A plurality of lower beads having U-shaped or C-shaped cross-sections that are open in the front-rear direction and project downward are formed in a corrugated plate shape continuously formed in the vehicle width direction. .

  According to this, a plurality of upper beads protruding upward in a U-shaped section or a C-shaped cross section in which the lower part continuous in the front-rear direction from the front end edge to the abutting part is opened on the rear upper surface are continuous in the vehicle width direction. A plurality of lower sides projecting downward in a U-shaped cross section or a C-shaped cross section in which the upper part continuous in the front-rear direction from the front end edge to the abutting part is opened. With a simple configuration in which the bead is formed in a corrugated shape continuously formed in the vehicle width direction, it is possible to secure a resistance against an impact load input from the front of the rear upper surface and the rear lower surface, and the rear impact part is easier than the front impact absorption part. The drag of can be set large.

  According to a third aspect of the present invention, in the shock absorber for the shock absorbing bumper for a vehicle according to the first aspect, the rear upper surface is open downward in the front-rear direction from the front edge of the rear upper surface to the contact portion. A triangular corrugated plate shape in which a plurality of upper beads having a V-shaped cross section projecting upward are continuously formed in the vehicle width direction, and the rear lower surface extends from the front edge of the rear lower surface to the abutting portion. A plurality of lower beads having a V-shaped cross section that opens upward in the direction and protrudes downward has a triangular wave plate shape formed continuously in the vehicle width direction.

  According to this, a triangular wave plate having a plurality of V-shaped upper beads which are continuously formed in the vehicle width direction, with the rear upper surface extending from the front end edge to the contact portion in the front-rear direction and opened downward and protruding upward. A triangular wave in which a plurality of upper-side beads having a V-shaped cross-section are formed continuously in the vehicle width direction, with the rear lower surface extending from the front end edge to the abutting portion and extending upward in the front-rear direction. With a simple configuration formed in a plate shape, the resistance against the impact load input from the front can be set larger in the rear impact portion than in the front impact absorption portion.

  According to a fourth aspect of the present invention, in the shock absorber for the shock absorbing bumper for a vehicle according to the first aspect, a bead in which one of the rear upper surface and the rear lower surface continues from the front edge to the contact portion is continuous in the vehicle width direction. It is formed, and the other is a flat surface.

  According to this, the deformation resistance of the rear upper surface and the rear lower surface can be made different according to the input direction of the impact load, and the behavior such as the tilting of the shock absorber when the impact load is input is limited and the impact absorption. Good impact energy absorption by the material can be secured.

  According to the present invention, in the initial stage where an impact load is applied to the top surface, the front impact absorbing portion formed by the front upper surface and the front lower surface is gently crushed, and the initial impact absorption is not caused without abruptly rising the initial drag. In the intermediate stage after the deformation of the part, the rear upper surface and rear lower surface of the rear impact part are gently crushed and deformed to suppress a sudden deformation drag and increase the deformation stroke, ensuring good shock energy absorption it can.

It is a principal part perspective view which shows the outline | summary of the shock absorber bumper for vehicles which concerns on 1st Embodiment. It is the II-II sectional view taken on the line of FIG. It is a partially broken perspective view of an impact absorbing material. It is the IV-IV sectional view taken on the line of FIG. It is the VV sectional view taken on the line of FIG. It is a figure which shows typically the crushing mode of the impact-absorbing material accompanying an impact load input. It is a FS (load-deformation stroke) correlation diagram. It is a GS (acceleration-deformation stroke) correlation diagram. It is a principal part perspective view which shows the outline | summary of the absorption bumper for vehicles which concerns on 2nd Embodiment. It is a partially broken perspective view of an impact absorbing material. It is the XX sectional view taken on the line of FIG. It is sectional drawing which shows the outline | summary of the conventional impact-absorbing bumper for vehicles. It is sectional drawing which shows the outline | summary of the conventional impact-absorbing bumper for vehicles. It is a FS (load-deformation stroke) correlation diagram.

(First embodiment)
Hereinafter, a first embodiment of a shock absorber for a shock absorber for a vehicle according to the present invention will be described with reference to FIGS. In each figure, arrow F indicates the vehicle front direction, and arrow W indicates the vehicle width direction.

  FIG. 1 is a perspective view of an essential part showing an outline of a vehicular absorption bumper 1, and FIG. 2 is a cross-sectional view taken along line II-II in FIG. The shock absorbing bumper 1 is disposed at the front of the vehicle body and extends in the vehicle width direction along the bumper beam 2 that extends in the vehicle width direction, the bumper face 7 that forms the outer surface of the bumper 1, and the front surface 3 of the bumper beam 2. And an impact absorbing material 10 which is covered by the bumper face 7.

  The bumper beam 2 is made of a steel plate having excellent rigidity, and extends in the vehicle width direction in a substantially hollow rectangular cross-sectional shape having a substantially rectangular front surface 3, upper surface 4, lower surface 5 and rear surface 6 elongated in the vehicle width direction. In addition, both ends are supported via brackets at the front ends of the body frame such as left and right side members extending in the vehicle width direction (not shown). Further, the upper locking hole 31 and the lower portion of the slit-like structure constituting the shock absorbing material locking means 30 together with the upper locking portion 33 and the lower locking portion 34 of the shock absorbing material 10 described later on the upper portion 3a and the lower portion 3b of the front surface 3. A plurality of the locking holes 32 are opened apart from each other in the vehicle width direction.

  The bumper face 7 is formed of a resin such as polyurethane or polypropylene, and the shock absorber 10 is formed of a resin such as polypropylene that can be easily molded by injection molding or compression-pneumatic molding, has excellent productivity, and can ensure product shape accuracy. ing.

  The shock absorber 10 will be described in detail with reference to FIGS. 3 is a partially broken perspective view of the shock absorber 10, FIG. 4 is a sectional view taken along line IV-IV in FIG. 3, and FIG. 5 is a sectional view taken along line VV in FIG.

  The shock absorber 10 has a top surface 12 having an arc-shaped cross section that forms the front surface of the shock absorber 10, the upper edge 12a and the lower edge 12b of the top surface 12 are each smoothly curved and continuously rearward from the top surface 12. A front impact absorbing portion 11 having a substantially U-shaped cross section having a front upper surface 13 and a front lower surface 14 that gradually separate from each other as they are separated from each other, and a front edge 22a is continuous with a rear end of the front upper surface 13. The rear upper surface 22 and the front end edge 25a are formed in the shape of a plate, the upper flange 24 serving as a contact portion that can contact the rear end edge 22b along the upper portion 3a of the front surface 3 of the bumper beam 2 is bent upward. A rear lower surface 27 having a plate-like shape that is continuous with the rear end of the lower surface 14, and a lower flange 27 serving as a contact portion that can contact the rear end edge 25 b along the lower portion 3 b of the front surface 3 of the bumper beam 2. 25 width direction A rear shock absorber 21 consecutive are integrally formed.

  The rear upper surface 22 and the rear lower surface 25 of the rear shock absorber 21 are opposed to each other in a tapered shape that gradually separates from the front edge 22a, 25a side toward the rear edge 22b, 25b, and the rear upper surface 22 An upper bead 26 that protrudes upward in a U-shaped or C-shaped cross section with the lower side continuous in the front-rear direction extending from the front edge 22a to the upper flange 23 is formed across the entire width in the vehicle width direction. 4 is formed into a corrugated plate shape having a waveform as shown in FIG. Similarly, on the rear lower surface 25, a lower bead 26 that protrudes downward in a U-shaped or C-shaped cross section in which an upper side continuous in the front-rear direction from the front end edge 25a to the lower flange 27 is opened is a vehicle width. The cross-sectional shape in the vehicle width direction is formed in a corrugated shape having a waveform as shown in FIG.

  Both sides of the front impact absorbing portion 11 and the rear impact absorbing portion 21 are planarly opposed to each other as they move rearward from the top surface 12, that is, from the front impact absorbing portion 11 side to the rear impact absorbing portion 21 side. It is closed by the side 29. Further, a plurality of hook-shaped upper locking portions 33 that protrude rearward from the upper end of the upper flange 24 and can be inserted into and locked in the upper locking holes 31 opened in the front surface 3 of the bumper beam 2 are separated in the vehicle width direction. A hook-like lower locking portion 34 that is formed and protrudes rearward from the lower end of the lower flange 27 and can be inserted into and locked into the lower locking hole 32 opened in the front surface 3 of the bumper 2 is separated in the vehicle width direction. Are formed. The shock absorber 10 is formed with an upper bead 23 and a lower bead 26 that are continuous in the front-rear direction on the rear upper surface 22 and the rear lower surface 25, so that the resistance against an impact load input from the front is increased. Further, the rear impact absorbing portion 21 is set larger.

  The attack absorber 10 thus formed includes a front upper surface 13 and a rear upper surface 22 that are continuously formed on the upper edge 12a of the top surface 12, and a front lower surface 14 that is continuously formed on the lower edge 12b of the top surface 12. The rear lower surface 25 has a substantially U-shaped cross-section that gradually separates from the top surface 12, and the upper flange 24 and the lower flange 27 are bent upward and downward from each other, and the lower surface is opened. The upper bead 23 that is U-shaped or C-shaped and continuous in the front-rear direction reaches the upper flange 24, and the lower bead 26 that has a U-shaped or C-shaped cross section that is open on the upper side reaches the lower flange 27. In addition, it is possible to ensure a slip-off gradient in the molding die when molding by injection molding, compression pneumatic molding or the like, and to ensure excellent productivity and product shape accuracy. Further, the shock absorber 10 is made of a resin having a substantially U-shape and a hollow cross-sectional shape continuous in the vehicle width direction, and can be configured to be relatively light.

  As shown in FIGS. 1 and 2, the shock absorbing material 10 configured in this way includes an upper locking hole 31 and a lower portion that open each upper locking portion 32 and lower locking portion 33 to the front surface 3 of the bumper beam 2. A state in which the upper flange 23 and the lower flange 27 are in contact with the upper part 3a and the lower part 3b of the front surface 3 of the bumper beam 2 and extend to the front surface 3 of the bumper beam 2 in the vehicle width direction. Thus, the upper locking portions 33 and the lower locking portions 34 are locked to the upper locking holes 31 and the lower locking holes 32 and attached to the front surface 3 of the bumper beam 2.

  The bumper 1 is formed by covering the bumper beam 2 with the bumper face 7 in a state where the bumper beam 2 is mounted on the front surface 3 of the bumper beam 2, and both ends of the bumper beam 2 are attached to the left and right side members through the brackets. A bumper 1 is attached to the front of the vehicle body by being attached to the vehicle body frame.

  Next, the operation of the shock absorbing bumper 1 configured as described above will be described with reference to FIGS. FIG. 6 is a diagram schematically showing a crushing mode of the shock absorber 10 in response to an impact load input, FIG. 7 is a FS (load-deformation stroke) correlation diagram, and FIG. 8 is a GS (acceleration-deformation stroke). It is a correlation diagram.

  When a vehicle equipped with the impact bumper 1 comes into contact with an external object or a leg of a pedestrian, for example, a pedestrian, and an impact load is applied to the bumper 1 from the front, the bumper face 7 is passed through FIG. The impact load P is input from the top surface 12 to the shock absorber 10 as shown in FIG.

  When the shock load P is input and the shock absorber 10 is compressed in the front-rear direction, the front shock absorber 11 formed by the top surface 12, the front upper surface 13, and the front lower surface 14 continues in the front-rear direction. Since the deformation resistance is set to be small with respect to the rear impact absorbing portion 25 having the corrugated rear upper surface 22 and the rear lower surface 25 in which a plurality of upper beads 23 and lower beads 26 are formed, FIG. As shown in b), the front upper surface 13 and the front lower surface 14 are crushed and deformed as the top surface 12 is retracted, and a deformation drag is generated along with the crushed deformation.

  The initial deformation due to the crush of the front shock absorber 11 of the shock absorber 10 is such that the front shock absorber 11 has a substantially U-shaped cross section in which the front upper surface 13 and the front lower surface 14 are continuous with the top surface 12. The upper surface 13 and the front lower surface 14 are successively crushed and deformed while maintaining a balance, and gradually collapsed with respect to the load as shown in the FS correlation diagram of FIG. As shown in the GS correlation diagram, the initial acceleration is suppressed and the impact is alleviated.

  When the front impact absorbing portion 11 is crushed and deformed as shown in FIG. 6 (c), the front impact absorbing portion 11 that has been crushed and deformed following the initial deformation mainly moves backward and forward as shown in FIG. As shown in (e), the rear upper surface 22 and the rear lower surface 25 of the rear shock absorber 25 are crushed and deformed. The crushing deformation of the rear upper surface 22 and the rear lower surface 25 is input from the front shock absorber 11 because the upper beads 23 and the lower beads 26 are distributed in a corrugated shape on the rear upper surface 22 and the rear lower surface 25, respectively. 7 is distributed over a wide range, local deformation is suppressed, and the rear upper surface 22 and the rear lower surface 25 are successively crushed and deformed while maintaining balance, as shown in the FS correlation diagram of FIG. The acceleration is suppressed and the impact is alleviated as shown in the GS correlation diagram in FIG.

  Therefore, according to the bumper 1 including the impact absorbing material 10 in the present embodiment having the above-described configuration, the front impact absorbing portion 11 is gently crushed and the initial drag is rapidly increased in the initial stage where the impact load is applied. Without rising, in the intermediate stage after the deformation of the front shock absorber 11, the load input from the front shock absorber 11 is dispersed over a wide range, local deformation is suppressed, and the crush is deformed gently. Rapid deformation drag is suppressed, deformation stroke is increased, good impact energy absorption is ensured, and damage to the pedestrian's legs is expected to be extremely reduced even when in contact with the pedestrian it can.

  Further, the shock absorber 10 can be configured to be relatively lightweight with a hollow cross-sectional shape, the weight of the bumper 1 can be reduced, and the shock absorber 10 can be easily formed by injection molding or compression pneumatic molding with excellent productivity. Accuracy can be ensured and manufacturing costs can be reduced.

  In addition, depending on the required shock energy absorption according to the specifications and the like, the length in the front-rear direction of the front shock absorber 11 and the rear shock absorber 21, the upper ribs 23 formed on the rear upper surface 22 and the rear lower surface 25, The impact energy absorption characteristics can be set and changed by appropriately changing the size of the lower rib 25 or the thickness of the shock absorber 10.

  Further, considering the input direction of the impact load, the upper ribs 23 formed on the rear upper surface 22 and the lower ribs 26 formed on the rear lower surface 25 are formed in different shapes to change the corrugated plate shape, or on the rear upper surface 22. One of the upper rib 23 formed or the lower rib 26 formed on the rear lower surface 25 may be omitted and formed on a flat surface so that the deformation resistance of the rear upper surface 22 and the rear lower surface 25 can be made different. As a result, the behavior of the shock absorber 10 such as tilting when an impact load is input, that is, the collapse is suppressed, and the shock energy absorption by the good deformation resistance of the front shock absorber 11 of the shock absorber 10 can be secured. .

(Second Embodiment)
A second embodiment of the shock absorbing material for a vehicle shock absorbing bumper according to the present invention will be described with reference to FIGS. In addition, in each FIG. 9 thru | or 11, the same code | symbol is attached | subjected to the part corresponding to FIG. 1 thru | or FIG. 8, and the detailed description of this part is abbreviate | omitted.

  FIG. 9 is a perspective view of a main part showing an outline of the vehicle impact absorbing bumper according to the present embodiment, FIG. 10 is a partially broken perspective view of the impact absorbing member 10, and FIG. 11 is a sectional view taken along line XX of FIG. is there.

  The shock absorbing bumper 1 in this embodiment includes a bumper beam 2, a bumper face 7, and a shock absorbing material 10 that extends in the vehicle width direction along the front surface 3 of the bumper beam 2 and is covered by the bumper face 7. The bumper beam 2 and the bumper face 7 are the same as those in the first embodiment, and the shock absorber 10 different from the first embodiment will be mainly described.

  As shown in FIGS. 10 and 11, the shock absorber 10 includes a front surface 12 and a front upper surface 13 and a front lower surface that are smoothly curved from the top edge 12 a and the lower edge 12 b of the top surface 12 and are continuously bent rearward. A front impact absorbing portion 11 having a substantially U-shaped cross section having 14 and a front end edge 22a which is continuous with the rear end of the front upper surface 13 and a rear end edge 22b on the front surface 3 of the bumper beam 2. A rear upper surface 22 in which an upper flange 24 capable of abutting along the upper portion 3a is bent upward, and a front end edge of the bumper beam 2 is formed in a plate shape in which the front end edge is continuous with the rear end of the front lower surface 14. The rear impact absorbing portion 21 is formed integrally with a rear lower surface 25 in which a lower flange 27 capable of contacting along the lower portion 3b is bent downward and continuous in the vehicle width direction.

  The rear upper surface 22 and the rear lower surface 25 of the rear shock absorber 21 are opposed to each other in a tapered shape that gradually separates from the front edge 22a, 25a side toward the rear edge 22b, 25b, and the rear upper surface 22 An upper bead 35 is formed across the entire width in the vehicle width direction with a V-shaped cross section with the lower side continuous in the front-rear direction extending from the front end edge 22a to the upper flange 23, and has a cross-sectional shape in the vehicle width direction. As shown in FIG. 11, it is formed in a triangular wave plate shape. Similarly, on the rear lower surface 25, a lower bead 36 that protrudes downward in a V-shaped cross section with the upper side continuous in the front-rear direction extending from the front end edge 25 a to the lower flange 27 extends across the entire width in the vehicle width direction. The cross-sectional shape in the vehicle width direction is formed in a triangular wave plate shape as shown in FIG. Both sides of the front impact absorbing portion 11 and the rear impact absorbing portion 21 are planarly opposed to each other as they move rearward from the top surface 12, that is, from the front impact absorbing portion 11 side to the rear impact absorbing portion 21 side. It is closed by the side 29.

  The shock absorber 10 is formed by forming a V-shaped upper bead 35 and a lower bead 36 continuous in the front-rear direction on the rear upper surface 22 and the rear lower surface 25 so that the rear upper surface 22 and the rear lower surface 25 have a triangular wave cross-sectional shape. By forming it in a plate shape, the rear impact absorbing portion 25 is set larger than the front impact absorbing portion 21 with respect to the impact load input from the front.

  The shock absorber 10 thus configured is mounted on the front surface 3 of the bumper beam 2 and is covered with the bumper face 7 to form the bumper 1.

  In the shock absorbing bumper 1 configured as described above, a vehicle including the shock bumper 1 comes into contact with an external object or a leg of a pedestrian, for example, a pedestrian, and an impact load is applied to the bumper 1 from the front. When the shock load P is input from the top surface 12 to the shock absorber 10 and the shock absorber 10 is compressed in the forward direction, the front shock absorber 11 has a plurality of upper sides continuous in the front-rear direction. The deformation resistance is set low with respect to the rear impact absorbing portion 25 having the corrugated rear upper surface 22 and the rear lower surface 25 in which the bead 35 and the lower bead 36 are formed. The front upper surface 13 and the front lower surface 14 are crushed and deformed, and the initial acceleration is suppressed and the impact is alleviated without the initial drag rising rapidly.

  Further, when the crushing deformation of the front shock absorbing portion 11 is completed, the rear upper surface 22 and the rear lower surface 25 of the rear shock absorbing portion 25 are crushed as the front shock absorbing portion 11 that has been deformed crushing following the initial deformation is retracted. Deform. The crushing deformation of the rear upper surface 22 and the rear lower surface 25 is input from the front shock absorber 11 because the upper bead 35 and the lower bead 36 are dispersed in a triangular corrugated shape on the rear upper surface 22 and the rear lower surface 25, respectively. The load is distributed over a wide range, local deformation is suppressed, the rear upper surface 22 and the rear lower surface 25 are gradually crushed while maintaining a balance, and the impact is mitigated without a sudden increase in deformation drag .

  Therefore, according to the bumper 1 including the impact absorbing material 10 in the present embodiment having the above-described configuration, the front impact absorbing portion 11 is gently crushed and the initial drag is rapidly increased in the initial stage where the impact load is applied. Without rising, in the intermediate stage after the deformation of the front shock absorber 11, the load input from the front shock absorber 11 is dispersed over a wide range and local deformation is suppressed, so that the rear upper surface 22 and the rear lower surface 25 is gradually crushed and deformed while maintaining equilibrium, abrupt deformation resistance is suppressed, an increase in deformation stroke is obtained, good shock energy absorption is ensured, and a pedestrian is contacted. The damage to the pedestrian's legs can be greatly reduced.

  Further, in consideration of the input direction of the impact load, the upper bead 35 formed on the rear upper surface 22 and the lower bead 36 formed on the rear lower surface 25 are formed in different shapes to change the triangular wave plate shape, or on the rear upper surface 22. One of the formed upper bead 35 and the lower bead 36 formed on the rear lower surface 25 may be omitted to form a flat surface so that the deformation resistance of the rear upper surface 22 and the rear lower surface 25 can be made different. As a result, the behavior of the shock absorber 10 such as tilting when an impact load is input, that is, the collapse is suppressed, and the shock energy absorption by the good deformation resistance of the front shock absorber 11 of the shock absorber 10 can be secured. .

  The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, in the first embodiment, the cross-sectional shapes of the rear upper surface 22 and the rear lower surface 25 are corrugated, and in the second embodiment, the cross-sectional shapes of the rear upper surface 22 and the rear lower surface 25 are triangular wave plates. One of the upper surface 22 and the rear lower surface 25 may be corrugated and the other may be triangular corrugated. Moreover, it is also possible to divide the shock absorbing material into a plurality of continuous parts in the vehicle width direction.

  In each of the above embodiments, the shock absorbing material locking means 30 is configured by the upper locking holes 31 formed in the bumper beam 2 and the upper locking portions 33 and 34 formed in the shock absorbing material 32. It can also be formed by other configurations such as bolts and nuts.

DESCRIPTION OF SYMBOLS 1 Vehicle absorption bumper 2 Bumper beam 3 Front surface 7 Bumper face 10 Shock absorber 11 Front shock absorber 12 Top surface 12a Upper edge 12b Lower edge 13 Front upper surface 14 Front lower surface 21 Rear shock absorber 22 Rear upper surface 22a Front edge 22b Rear end edge 23 Upper bead 24 Upper flange (contact portion)
25a Front end edge 25b Rear end edge 26 Lower bead 27 Lower flange (contact portion)
29 Side 35 Upper bead 36 Lower bead

Claims (4)

In a shock absorber for a resin vehicle shock absorbing bumper disposed extending in the vehicle width direction between the front surface of the bumper beam extending in the vehicle width direction and the bumper face,
A front portion extending in the vehicle width direction with a top surface extending in the vehicle width direction and a front upper surface and a front lower surface that are curved and continuous from the top edge and the lower edge of the top surface, respectively. An impact absorber,
The front end edge is continuous with the rear end of the front upper surface and the rear end surface is formed with an abutting portion that contacts the front surface of the bumper beam, and the rear upper surface is opposed to the rear upper surface, and the front end edge is behind the front lower surface. A rear impact absorbing portion having a rear lower surface formed with an abutting portion that is continuous with the end and abutted against the front surface of the bumper beam at the rear edge, and has a resistance against an impact load input from the front than the front impact absorbing portion. A shock absorbing material for a vehicle shock absorbing bumper, wherein the rear shock absorbing portion is set large. The rear upper surface has a plurality of U-shaped or C-shaped upper beads protruding in the vehicle width direction, with the lower portion continuous in the front-rear direction extending from the front edge of the rear upper surface to the contact portion. A continuously formed corrugated plate shape,
The rear lower surface has a plurality of U-shaped or C-shaped lower beads protruding in the vehicle width direction, with the upper part continuous in the front-rear direction extending from the front edge of the rear lower surface to the abutting part. The shock absorbing material for a shock absorbing bumper for a vehicle according to claim 1, wherein the shock absorbing material has a corrugated shape continuously formed on the shock absorbing bumper. The rear upper surface is formed with a plurality of V-shaped upper beads continuously extending in the vehicle width direction, with the lower portion continuous in the front-rear direction extending from the front edge of the rear upper surface to the abutting portion, and protruding upward. A triangular wave plate,
The rear lower surface is formed with a plurality of lower beads having a V-shaped cross section that are continuously open in the vehicle width direction and open upward in the front-rear direction from the front edge of the rear lower surface to the contact portion and project downward. 2. The shock absorbing material for a vehicle shock absorbing bumper according to claim 1, wherein the shock absorbing material has a triangular wave plate shape.   2. The vehicle impact according to claim 1, wherein a bead in which one of the rear upper surface and the rear lower surface continues from the front edge to the contact portion is continuously formed in the vehicle width direction, and the other has a flat surface shape. Shock absorber for absorbing bumper.

Images