Title of the invention: Closed-section structural material with high collision performance and automobile body frame
Technical field
[0001]
　The present invention relates to a closed cross-section structural material that exhibits high energy absorption performance, for example, at the time of a frontal collision of an automobile.
Background technology
[0002]
　The bumper structure is an example of a structure that exhibits high energy absorption performance in the event of a vehicle collision. The bumper structure of an automobile consists of a bumper beam and a crash box. For example, in a frontal collision of an automobile, especially in a light collision, the bumper beam bends and deforms, and the crash box crushes and deforms to absorb the impact and apply a load to the rear of the automobile. I was trying not to convey it. At this time, the bumper beam plays a role as a collision energy absorption site.
[0003]
　In recent years, fuel economy regulations have been tightened all over the world, and weight reduction of automobile bodies has been promoted. On the other hand, collision safety has also been tightened, and both improvement in collision performance and weight reduction are required, and automobile manufacturers are developing high-strength and thin-walled bodies and electric vehicles. Especially in electric vehicles, it is required to increase the cruising range, and a body structure with a large capacity battery mounted under the floor has begun to be developed. As a result, the wheelbase becomes longer, and it is necessary to absorb the same collision energy as a gasoline vehicle with a short front overhang. Therefore, the bumper beam is required to have high buckling resistance and absorbed energy performance. Further, in gasoline-powered automobiles, weight reduction of the vehicle body is also required, and a lightweight bumper beam having high buckling resistance and absorbed energy performance is required.
[0004]
　Some conventional bumper beams are described in Patent Documents 1 and 2. Patent Document 1 discloses a structure in which three closed cross sections are formed inside the bumper beam by providing another hat-shaped member inside the hat-shaped member. In the structure of Patent Document 1, a recess is formed on the top surface of the outer hat-shaped member of the two hat-shaped members, and the recess is located in the central region of the above-mentioned three regions. Patent Document 2 discloses an invention in which two closed-section spaces are arranged so as to include two ridges between a side surface and a rear surface in a bumper beam having a closed-section structural material.
Prior art literature
Patent documents
[0005]
Patent Document 1: Japanese Patent Application Laid-Open No. 2010-120581
Patent Document 2: Japanese Patent Application Laid-Open No. 2015-193383
Outline of the invention
Problems to be solved by the invention
[0006]
　However, in Patent Document 1, although the side surface of the inner hat-shaped member is suppressed from collapsing when the bumper beam is bent and deformed by the concave shape, the outer side serving as the buckling starting point of the bumper beam itself. It is not possible to prevent the side surface of the hat-shaped member from collapsing. Therefore, there is room for improvement in the mass efficiency of the absorbed energy performance of the bumper beam. Further, Patent Document 2 intentionally weakens the rigidity of the contact surface to moderate the increase in the collision load. Therefore, buckling is caused at an early stage in the event of a collision, and there is room for improvement in mass efficiency regarding absorbed energy performance. Furthermore, by causing buckling during a light collision, the amount of the bumper beam retreating to the rear of the vehicle body increases, which may interfere with the radiator support core and significantly reduce the repairability of the vehicle body.
[0007]
　The present invention has been made in view of such problems of the prior art, and has high proof stress (that is, suppression of the amount of members invading the inside of the vehicle) and high absorption by suppressing cross-sectional collapse at the time of a collision. An object of the present invention is to provide a closed cross-section structural material having energy performance.
Means to solve problems
[0008]
　In order to solve the above problems, the present inventor has simulated a closed cross-section structural material composed of a hat-shaped member and a closing plate in which a pole collides with the top surface of the hat-shaped member from a direction perpendicular to the longitudinal direction of the member. carried out. As a result of examining the relationship between the cross-sectional collapse behavior of the closed-section structural material and the amount of energy absorbed under the above conditions, (a) the collapse of the pair of side wall portions of the closed-section structural material was suppressed, and (b) the closed-section structural material It was found that the closed cross-section structural material exhibits high strength and high absorption energy performance by imparting flexural rigidity to the collision side wall, which is the wall on the collision side. Based on this finding, the present invention has been completed.
[0009]
　One aspect of the present invention is a closed-section structural material, which has a collision side wall portion, an anti-collision side wall portion, a first side wall portion, and a second side wall portion in a cross section having a normal in the longitudinal direction of the member. A hollow member having a side wall portion, a first inner side wall portion, a second inner side wall portion, a third inner side wall portion, and a fourth inner side wall portion is provided, and the collision side wall portion is on the collision side. The anti-collision side wall portion is a wall portion facing the collision side wall portion and opposite to the collision side, and the first side wall portion and the second side wall portion are the said. A pair of wall portions connected to an end portion of the collision side wall portion and an end portion of the anti-collision side wall portion, and the first inner side wall portion extends from the first side wall portion to the inside of the hollow member. It is a wall portion, the second inner side wall portion is a wall portion extending from the second side wall portion to the inside of the hollow member, and the third inner side wall portion is the first inner side wall portion. It is a wall portion connected to the collision side wall portion, and the fourth inner side wall portion is a wall portion connected to the second inner side wall portion and the collision side wall portion.
[0010]
　One aspect of the present invention from another aspect is that the vehicle body skeleton is provided with the above-mentioned closed cross-section structural material, and the collision side wall portion is located outside the vehicle with respect to the anti-collision side wall portion. It is a feature.
[0011]
　1 and 2 are views showing an example of a vehicle body skeleton 70 including a closed cross-section structural material. The closed-section structural material according to the present invention is applied as, for example, the front bumper beam and side sill of an automobile shown in FIG. 1 and the rear bumper beam shown in FIG. 2, but the applicable parts are not limited thereto. Further, the "collision side" according to the present invention is a side that comes into contact with another vehicle or the like at the time of a collision, and refers to the outside of the vehicle or the inside of the vehicle. For example, when the closed cross-section structural material is a front bumper beam, the front side in the vehicle length direction corresponds to the outside of the vehicle, so the front side is the collision side. In this case, since the rear side in the vehicle length direction corresponds to the inside of the vehicle, the rear side is the anti-collision side. Further, for example, when the closed cross-section structural material is a rear bumper beam, the rear side in the vehicle length direction corresponds to the outside of the vehicle, so that the rear side is the collision side. In this case, since the front side in the vehicle length direction corresponds to the inside of the vehicle, the front side is the anti-collision side. Further, for example, when the closed cross-section structural material is a side sill, the outside of the vehicle in the vehicle width direction is the collision side, and the inside of the vehicle in the vehicle width direction is the anti-collision side.
Effect of the invention
[0012]
　According to the present invention, it is possible to provide a closed cross-section structural material having high proof stress and high absorption energy performance by suppressing cross-section collapse at the time of collision.
A brief description of the drawing
[0013]
[Fig. 1] Fig. 1 is a diagram showing an example of a vehicle body skeleton.
[Fig. 2] Fig. 2 is a diagram showing an example of a vehicle body skeleton.
FIG. 3 is a cross-sectional view showing a schematic configuration of a bumper beam according to a first embodiment of the present invention, with the member longitudinal direction as a normal.
FIG. 4 is a cross-sectional view showing a schematic configuration of a conventional bumper beam with the member longitudinal direction as a normal.
FIG. 5 is a cross-sectional view showing a schematic configuration of a bumper beam according to a second embodiment of the present invention, with the member longitudinal direction as a normal.
FIG. 6 is a cross-sectional view showing a schematic configuration of a bumper beam according to a third embodiment of the present invention, with the member longitudinal direction as a normal.
FIG. 7 is a cross-sectional view showing a schematic configuration of a bumper beam according to a fourth embodiment of the present invention, with the member longitudinal direction as a normal.
FIG. 8 is a diagram showing an example of a bumper beam when a plurality of convex portions are provided.
[Fig. 9] Fig. 9 is a diagram showing a shape example of reinforcement.
[Fig. 10] Fig. 10 is a diagram showing a shape example of reinforcement.
FIG. 11 is a diagram showing an example of a closed cross-section structural material according to the present invention.
FIG. 12 is a diagram showing an example of a closed cross-section structural material according to the present invention.
FIG. 13 is a diagram showing an example of a closed cross-section structural material according to the present invention.
FIG. 14 is a diagram showing an example of a closed cross-section structural material according to the present invention.
FIG. 15 is a diagram showing an example of a closed cross-section structural material according to the present invention.
FIG. 16 is a cross-sectional view showing a schematic configuration of a bumper beam of a comparative example, with the member longitudinal direction as a normal.
FIG. 17 is a cross-sectional view showing a schematic configuration of a bumper beam of a comparative example, with the member longitudinal direction as a normal.
[Fig. 18] Fig. 18 is a diagram showing collision analysis conditions.
FIG. 19 is a load-stroke diagram in a simulation of a conventional structure and a structure according to the present invention.
FIG. 20 is a load-stroke diagram in a simulation of a conventional structure and a structure according to the present invention.
Mode for carrying out the invention
[0014]
　Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the present specification and the drawings, elements having substantially the same functional configuration are designated by the same reference numerals to omit duplicate description.
[0015]
　In the following description, a bumper beam will be described as an example of the closed cross-section structural material, but if the same closed cross-section structural material is used, the deformation mode as described in the present embodiment will be exhibited, and the maximum at the time of collision will be exhibited. The load and absorbed energy can be increased. That is, the closed cross-section structural material is not limited to the bumper beam.
[0016]
The
　closed cross-sectional structural material shown in FIG. 3 has a collision side wall portion 11, an anti-collision side wall portion 12, and a first side wall portion 13 in a cross section having a member longitudinal direction Y as a normal. A hollow member 10 having a second side wall portion 14, a first inner side wall portion 15, a second inner side wall portion 16, a third inner side wall portion 17, and a fourth inner side wall portion 18 is provided. ing. The collision side wall portion 11 is a wall portion located on the collision side. The anti-collision side wall portion 12 is a wall portion facing the collision side wall portion 11 and opposite to the collision side. The first side wall portion 13 and the second side wall portion 14 are a pair of wall portions connected to the end portion of the collision side wall portion 11 and the end portion of the anti-collision side wall portion 12. The first inner side wall portion 15 is a wall portion extending inward of the hollow member 10 from the first side wall portion 13. The second inner side wall portion 16 is a wall portion extending inward of the hollow member 10 from the second side wall portion 14. The third inner side wall portion 17 is a wall portion connected to the first inner side wall portion 15 and the collision side wall portion 11. The fourth inner side wall portion 18 is a wall portion that connects the second inner side wall portion 16 and the collision side wall portion 11.
[0017]
　In the first embodiment, the bumper beam 1 as an example of the closed cross-section structural material is composed of a closing plate 25 forming the inner member 2, a hat-shaped member 30 forming the outer member 3, and a reinforcement 40. Has been done. The closing plate in the present specification is a plate that covers the opening side of the hat-shaped member.
[0018]
　The hat-shaped member 30 has two flanges 30a and 30b extending in the Z direction (in the case of a bumper beam, the vehicle height direction) in a cross section having the member longitudinal direction Y (in the case of a bumper beam, the vehicle width direction) as a normal. A pair of side surfaces 30c and 30d extending from one end of each of the flanges 30a and 30b to the outside of the vehicle in the X direction (in the case of a bumper beam, the vehicle length direction) and a top surface 30e connecting the ends of the pair of side surfaces 30c and 30d. And have. A convex portion 50 projecting to the outside of the vehicle in the X direction is formed on the top surface 30e of the hat-shaped member 30, and the convex portion 50 is located at the central portion of the top surface 30e of the hat-shaped member 30 in the Z direction. .. Further, the convex portion 50 has a pair of side surfaces 50a and 50b connected to the top surface 30e of the hat-shaped member 30, and a top surface 50c connecting the ends of the pair of side surfaces 50a and 50b.
[0019]
　When the closed cross section structural material is a bumper beam, the X direction is the vehicle length direction, the Y direction is the vehicle width direction, and the Z direction is the vehicle height direction. Therefore, the outside of the vehicle in the X direction corresponds to the outside of the vehicle in the vehicle length direction of the bumper beam, that is, the collision side at the time of collision. Similarly, the inside of the vehicle in the X direction corresponds to the inside of the vehicle in the vehicle length direction of the bumper beam, that is, the anti-collision side at the time of collision. Further, for example, when the closed cross-section structural material is a side sill, the X direction is the vehicle width direction, the Y direction is the vehicle length direction, and the Z direction is the vehicle height direction. Therefore, when the closed cross-section structural material is a side sill, the collision side at the time of collision is the outside of the vehicle in the X direction, that is, the outside of the vehicle in the width direction of the side sill. Similarly, when the closed cross-section structural material is a side sill, the anti-collision side at the time of collision is the inside of the vehicle in the X direction, that is, the inside of the vehicle in the width direction of the side sill. Considering the above points, the side surfaces 30c and 30d of the hat-shaped member 30 in the closed cross-section structural material such as the bumper beam 1 and the side sill collide with each other from one end of the flanges 30a and 30b in the cross section with the member longitudinal direction Y as the normal. In other words, it is formed so as to extend to the collision side of time.
[0020]
　The reinforcement 40 has a U-shape in a cross section with the member longitudinal direction Y as a normal, and the pair of side surfaces 40a and 40b in contact with the outer surface sides of the side surfaces 30c and 30d of the hat-shaped member 30 and the pair of side surfaces. It has a top surface 40c that connects the ends of 40a and 40b. The reinforcement 40 is provided so as to cover the top surface 30e and the convex portion 50 of the hat-shaped member 30.
[0021]
　The closing plate 25 and the hat-shaped member 30 are joined to each other by the flanges 30a and 30b of the hat-shaped member 30. The hat-shaped member 30 and the reinforcement 40 are joined to each other at the side surfaces 30c and 30d of the hat-shaped member 30 and the side surfaces 40a and 40b of the reinforcement 40. Further, the top surface 50c of the convex portion 50 of the hat-shaped member 30 is joined to the inner surface side of the top surface 40c of the reinforcement 40. In the present embodiment, the hollow member 10 is formed by joining the inner member 2 and the outer member 3 in this way.
[0022]
　In the first embodiment, the collision side wall portion 11 is composed of the top surface 40c of the reinforcement 40 and the convex portion top surface 50c of the hat-shaped member 30, and the anti-collision side wall portion 12 is a closing plate 25 and a hat-shaped member. The flanges 30a and 30b of the 30 are formed, the first side wall portion 13 is composed of the side surface 40a of the reinforcement 40 and the side surface 30c of the hat-shaped member 30, and the second side wall portion 14 is the reinforcement 40. It is composed of a side surface 40b and a side surface 30d of the hat-shaped member 30. Further, in the first embodiment, the first inner side wall portion 15 and the second inner side wall portion 16 are the top surface 30e of the hat-shaped member 30, respectively, and the third inner side wall portion 17 is the hat-shaped member. The side surface 50a of the convex portion 50 of the 30 and the fourth inner side wall portion 18 is the side surface 50b of the convex portion 50 of the hat-shaped member 30. In the present embodiment, the length a in the X direction of the hollow member 10 (distance from the closing plate 25 to the top surface 40c of the reinforcement 40) is the width c of the reinforcement 40 (distance between the side surfaces 40a and 40b). ) Is longer than.
[0023]
　The hollow member 10 in the first embodiment has a closed cross section A formed by a closing plate 25 and a hat-shaped member 30. In other words, the anti-collision side wall portion 12, a part of the first side wall portion 13, the first inner side wall portion 15, the third inner side wall portion 17, a part of the collision side wall portion 11, and the fourth. A closed cross section A is formed in a region surrounded by the inner side wall portion 18, the second inner side wall portion 16, and the second side wall portion 14. That is, the closed cross-section structural material having such a closed cross-section A has a structure in which only one convex portion 50 is provided on the top surface 30e of the hat-shaped member 30. In addition to the above-mentioned closed cross section A, the bumper beam 1 has a total of three closed cross sections A to C, two closed cross sections B and C in which the space between the hat-shaped member 30 and the reinforcement 40 is divided by a convex portion 50. have. The method of joining the members is not particularly limited, but the members are joined by, for example, spot welding, laser welding, arc welding, or the like. The bumper beam 1 of the first embodiment is configured as described above.
[0024]
　Here, in the case of the conventional bumper beam 100 composed of the closing plate 25 and the hat-shaped member 101 as shown in FIG. 4, when a load is input to the top surface 101e (collision surface) of the hat-shaped member 101 at the time of collision, the ceiling A compressive stress acts on the ridges 101f and 101g between the surface 101e and the pair of side surfaces 101c and 101d, and the side surfaces 101c and 101d receive moments such as falling outward, respectively. Therefore, the buckling resistance is lowered due to the collapse of the top surface 101e of the hat-shaped member 101 and the ridges 101f and 101g. Further, the load input to the side surfaces 101c and 101d is reduced due to the collapse of the side surfaces 101c and 101d of the hat-shaped member 101 to the outside.
[0025]
　On the other hand, in the bumper beam 1 of the first embodiment shown in FIG. 3, when a load is input to the top surface 40c (collision surface) of the reinforcement 40 at the time of collision, the bumper beam 1 and the top surface 40c of the reinforcement 40 , The compressive stress acts on the ridges 40d and 40e between the top surface 40c and the side surfaces 40a and 40b. A load is also input to the top surface 50c of the convex portion 50 joined to the top surface 40c of the reinforcement 40, and the ridge line between the top surface 50c of the convex portion 50 and the top surface 50c and the side surfaces 50a and 50b. Compressive stress also acts on the parts 50d and 50e. Due to these compressive stresses, the side surfaces 40a and 40b of the reinforcement 40 receive moments to fall outward, while the side surfaces 30c and 30d of the hat-shaped member 30 receive moments to fall inward, respectively. receive. That is, a moment is generated on the side surfaces 30c and 30d of the hat-shaped member 30 and the side surfaces 40a and 40b of the reinforcement 40 to collapse on opposite sides, whereby the side surface as the outer member 3 is less likely to collapse. As a result, a high load can be received for a long time, and the maximum load and absorbed energy can be increased.
[0026]
　Further, in the conventional bumper beam 1 shown in FIG. 4, the closing plate 25 is an inner member and the hat-shaped member 101 is an outer member. However, in the bumper beam 1 of the first embodiment shown in FIG. The outer member 3 is composed of a hat-shaped member 30 and a reinforcement 40. That is, the side surfaces connected to the collision surface (the top surface 40c of the reinforcement 40 in this embodiment) as the outer member 3 to which the load is input are the side surfaces 30c and 30d of the hat-shaped member 30 and the side surfaces of the reinforcement 40. It is composed of 40a and 40b. Therefore, even if the length of the side surface (length in the X direction) of the outer member 3 is apparently the same as that of the conventional structure, the side surfaces having substantially the short length in the X direction are lined up. There is. As a result, the surface rigidity of the side surface of the outer member 3 is improved, and the side surface is less likely to fall down. As a result, a high load can be received for a long time at the time of collision, and the maximum load and absorbed energy can be increased.
[0027]
　Further, by forming the above-mentioned closed cross section by using the convex portion 50 on which the compressive stress acts at the time of collision, the bending rigidity of the top surface 40c of the reinforcement 40 is improved, and the maximum load is improved. As a result, buckling can be suppressed.
[0028]
　In the above-mentioned collision performance improving mechanism, (1) suppression of collapse of the side surfaces 30c and 30d of the hat-shaped member 30 and (2) addition of bending rigidity to the top surface 40c of the reinforcement 40 are the cross-sectional dimensions of the bumper beam 1. Maximum load and absorbed energy increase more effectively when is within a predetermined range.
[0029]
　Under the condition that the length a of the hollow member 10 in the X direction is constant, the height b of the convex portion 50 (the length in the X direction from the top surface 30e of the hat-shaped member 30 to the top surface 50c of the convex portion 50) is convex. The surface rigidity of the side surfaces 50a and 50b of the portion 50 and the surface rigidity of the side surfaces 30c and 30d of the hat-shaped member 30 change. Based on the examples described later, the ratio (b / a) of the height b of the convex portion 50 to the length a of the hollow member 10 in the X direction is preferably 0.15 to 0.35. Thereby, the maximum load and absorbed energy at the time of collision can be effectively increased. A more desirable lower limit for b / a is 0.17. A more desirable upper limit for b / a is 0.33.
[0030]
　Under the condition that the width c of the reinforcement 40 is constant, the surface rigidity of the top surface 50c of the convex portion 50 changes depending on the width d of the convex portion 50 (distance between the side surfaces 50a and 50b of the convex portion 50). Based on the examples described later, it is desirable that the width d of the convex portion 50 is smaller, but from the viewpoint of ensuring sufficient welding margins such as spot welding, laser welding and arc welding, the width d of the convex portion 50 is 10 mm. The above is desirable.
[0031]
As
　shown in FIG. 5, the bumper beam 1 of the second embodiment has a slanted wall portion 19 between the collision side wall portion 11 and the first side wall portion 13, and the collision side wall portion 19 is provided. A slanted wall portion 20 is provided between the portion 11 and the second side wall portion 14. In the present specification, the inclined wall portion 19 is a wall portion having a plane that is not parallel to each of the collision side wall portion 11 and the first side wall portion 13 in a cross section whose normal direction is the member longitudinal direction of the closed cross-section structural member. Is. Similarly, the inclined wall portion 20 in the present specification refers to a plane that is not parallel to each of the collision side wall portion 11 and the second side wall portion 14 in a cross section whose normal direction is the member longitudinal direction of the closed cross-section structural member. It is a wall part to have. The inclined wall portions 19 and 20 of the bumper beam 1 in the second embodiment correspond to the inclined surfaces 40f and 40g provided between the top surface 40c and the side surfaces 40a and 40b of the reinforcement 40. Since the slopes 40f and 40g are provided as an example of the sloped walls 19 and 20 as in the second embodiment, the absorbed energy at the time of collision can be increased as shown in the examples described later.
[0032]
　In the bumper beam 1 of the second embodiment, the height e1 and the width e2 of the inclined wall portions 19 and 20, that is, the slope 40f of the reinforcement 40 and the height e1 and the width e2 of 40 g are changed to form a hat shape. The deformation modes of the side surfaces 30c and 30d of the member 30 can be controlled. The height e1 of the inclined wall portion 19 (20) in the present specification is the length in the X direction from the collision side wall portion 11 to the boundary position between the inclined wall portion 19 (20) and the side wall portion 13 (14). is there. Further, the width e2 of the inclined wall portion 19 (20) in the present specification is the length in the Z direction from the side wall portion 13 (14) to the boundary position between the inclined wall portion 19 (20) and the collision side wall portion 11. ..
[0033]
　For example, when the height e1 of the slopes 40f and 40g is 0 (that is, when the slopes 19 and 20 are not provided), the side surfaces 30c and 30d of the hat-shaped member 30 are in a deformation mode in which they collapse inward. This is because the side surfaces 40a and 40b of the reinforcement 40 are offset in the Z direction with respect to the side surfaces 30c and 30d of the hat-shaped member 30, so that the load input to the side surfaces 40a and 40b of the reinforcement 40 is applied. This is to generate a moment that causes the side surfaces 30c and 30d of the hat-shaped member 30 to fall inward. On the other hand, when the height e1 of the slopes 40f and 40g is increased, a mode in which the side surfaces 30c and 30d of the hat-shaped member 30 collapse outward appears. This is because the load input to the slopes 40f and 40g generates a moment that causes the side surfaces 30c and 30d of the hat-shaped member 30 to fall outward, and the larger the height e1 of the slopes 40f and 40g, the larger the moment. Is.
[0034]
　By changing the height e1 of the slopes 40f and 40g in this way, the side surfaces 30c and 30d of the hat-shaped member 30 can be set to a deformation mode that is less likely to fall. Based on the examples described later, from the viewpoint of achieving both load efficiency and absorbed energy efficiency at a high level, the ratio of the height e1 of the slopes 40f and 40g to the length a of the hollow member 10 in the X direction (e1 /). a) is preferably 0.05 to 0.20. A more desirable lower limit for e1 / a is 0.08. A more desirable upper limit for e1 / a is 0.17. The ratio (e1 / e2) of the height e1 and the width e2 of the slopes 40f and 40g is preferably 0.6 to 1.5, and more preferably 0.9 to 1.1.
[0035]
As
　shown in FIG. 6, the bumper beam 1 of the third embodiment has a slanted wall portion formed between the first inner side wall portion 15 and the third inner side wall portion 17. It has an inner inclined wall portion 21 which is an inner inclined wall portion 21, and has an inner inclined wall portion 22 which is an inclined wall portion formed between the second inner side wall portion 16 and the fourth inner side wall portion 18. The inner inclined wall portion 21 in the present specification is not parallel to each of the first inner side wall portion 15 and the third inner side wall portion 17 in a cross section whose normal direction is the member longitudinal direction of the closed cross-sectional structural member. It is a wall portion having a flat surface. Similarly, the inner inclined wall portion 22 in the present specification refers to each of the second inner side wall portion 16 and the fourth inner side wall portion 18 in a cross section whose normal direction is the member longitudinal direction of the closed cross-sectional structural member. It is a wall portion having a plane that is not parallel to each other. In the third embodiment, the inner slopes 21 and 22 correspond to the slopes 50h and 50i provided between the top surface 30e of the hat-shaped member 30 and the side surfaces 50a and 50b of the convex portion 50. The height f1 of the inner inclined wall portion 21 (22) in the present specification is from the inner side wall portion 15 (16) to the boundary position between the inner side wall portion 21 (22) and the inner side wall portion 17 (18). Is the length in the X direction. Further, the width f2 of the inner inclined wall portion 21 (22) in the present specification is from the inner side wall portion 17 (18) to the boundary position between the inner side wall portion 21 (22) and the inner side wall portion 15 (16). The length in the Z direction.
[0036]
　In the bumper beam 1 of the third embodiment, the deformation modes of the side surfaces 30c and 30d of the hat-shaped member 30 can be controlled by changing the height f1 and the width f2 of the slopes 50h and 50i. For example, when the heights f1 of the slopes 50h and 50i are 0 (that is, when the inner slopes 21 and 22 are not provided), the side surfaces 30c and 30d of the hat-shaped member 30 are in a deformation mode in which they collapse inward. This is because the side surfaces 50a and 50b of the convex portion 50 are offset in the Z direction with respect to the side surfaces 30c and 30d of the hat-shaped member 30, so that the load input to the side surfaces 50a and 50b of the convex portion 50 is increased. This is to generate a moment that causes the side surfaces 30c and 30d of the hat-shaped member 30 to fall inward. On the other hand, as the height f1 of the slopes 50h and 50i is increased, a mode in which the side surfaces 30c and 30d of the hat-shaped member 30 collapse outward appears. This is because the load input to the slopes 50h and 50i generates a moment that causes the side surfaces 30c and 30d of the hat-shaped member 30 to fall outward, and the larger the height f1 of the slopes 50h and 50i, the larger the moment. Is.
[0037]
　By changing the heights f1 of the slopes 50h and 50i in this way, the side surfaces 30c and 30d of the hat-shaped member 30 can be set to a deformation mode that is less likely to fall. Based on the examples described later, from the viewpoint of achieving both load efficiency and absorbed energy efficiency at a high level, the ratio of the height f1 of the slopes 50h and 50i to the length a of the hollow member 10 in the X direction (f1 /). a) is preferably 0.05 to 0.20. A more desirable lower limit for f1 / a is 0.08. A more desirable upper limit for f1 / a is 0.17. Further, from the viewpoint of achieving both load efficiency and absorbed energy efficiency at a high level, it is desirable that the height f1 is less than the height b of the convex portion 50. The ratio (f1 / f2) of the height f1 and the width f2 of the slopes 50h and 50i is preferably 0.6 to 1.5, and more preferably 0.9 to 1.1.
[0038]
As
　shown in FIG. 7, the bumper beam 1 of the fourth embodiment includes the bumper beam 1 of the second embodiment shown in FIG. 5 and the bumper beam 1 of the third embodiment shown in FIG. It has a structure in which the bumper beam 1 is combined, and slopes 40f and 40g are formed on the reinforcement 40, and slopes 50h and 50i are formed on the convex portion 50. In other words, the bumper beam 1 of the fourth embodiment has a slanted wall portion 19 between the collision side wall portion 11 and the first side wall portion 13, and is between the collision side wall portion 11 and the second side wall portion 14. Has an inclined wall portion 20 and has an inner inclined wall portion 21 between the first inner side wall portion 15 and the third inner side wall portion 17, and has a second inner side wall portion 16 and a fourth inner wall surface portion 16. It is a structure having an inner inclined wall portion 22 between the portion 18 and the portion 18. In the bumper beam 1 having such a structure, the absorbed energy at the time of collision can be further increased.
[0039]
　Although one embodiment of the present invention has been described above, the present invention is not limited to such an example. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the technical idea described in the claims, and of course, the technical scope of the present invention also includes them. It is understood that it belongs to.
[0040]
　For example, as shown in FIG. 8, a plurality of convex portions 50 may be provided, and in this case, the absorbed energy at the time of collision can be further increased. In the example shown in FIG. 8, two convex portions 50 are provided, and in this case, the hollow member 10 is composed of four closed cross sections. That is, the hollow member 10 is composed of three or more closed cross sections according to the number of convex portions 50. In the example shown in FIG. 8, the anti-collision side wall portion 12, a part of the first side wall portion 13, the first inner side wall portion 15, the third inner side wall portion 17, and the collision side wall portion 11 Two closed cross sections are formed in a region surrounded by a part of the above, a fourth inner side wall portion 18, a second inner side wall portion 16, and a second side wall portion 14. It is desirable that only one convex portion 50 is formed from the viewpoint of achieving both improvement of absorbed energy at the time of collision and weight reduction at a high level. That is, the anti-collision side wall portion 12, a part of the first side wall portion 13, the first inner side wall portion 15, the third inner side wall portion 17, a part of the collision side wall portion 11, and the fourth. It is desirable that one closed cross-section space is formed in the region surrounded by the inner side wall portion 18, the second inner side wall portion 16, and the second side wall portion 14.
[0041]
　Further, the reinforcement 40 may be provided over the entire length of the hat-shaped member 30 in the longitudinal direction as shown in FIG. 9, and the collision load input portion is specified to some extent from the shape and mounting position of the bumper beam 1. If possible, as shown in FIG. 10, it may be only partially provided in the collision load input portion and its periphery. When the reinforcement 40 is partially provided in this way, the absorbed energy at the time of a collision can be sufficiently increased, and the weight can be reduced.
[0042]
　Further, in the above embodiment, the bumper beam 1 is composed of three parts, that is, a closing plate 25, a hat-shaped member 30, and a reinforcement 40. However, the closed cross-section structural material according to the present invention has been described in the above embodiment. Not limited to things. For example, the closed cross-section structural material may be a member as shown in FIGS. 11 to 15. The closed cross-section structural members shown in FIGS. 11 to 15 may be integrally molded by, for example, extrusion molding, or may be formed by joining a plurality of members to each other by welding or the like.
[0043]
　Even in such a closed cross-section structural material, as described in the above embodiment, the hollow member 10 has the collision side wall portion 11, the anti-collision side wall portion 12 facing the collision side wall portion 11, and the end of the collision side wall portion 11. It includes a pair of first side wall portions 13 and a second side wall portion 14 that are connected to the portion and the end portion of the anti-collision side wall portion 12. Further, the hollow member 10 includes a first inner side wall portion 15 extending inward from the first side wall portion 13 to the inside of the hollow member 10, and a second inner side wall portion extending inward from the second side wall portion 14 to the inside of the hollow member 10. 16, a third inner side wall portion 17 connected to the first inner side wall portion 15 and the collision side wall portion 11, and a fourth inner side wall portion 18 connected to the second inner side wall portion 16 and the collision side wall portion 11. ,have.
[0044]
　In the example shown in FIG. 11, the first inner side wall portion 15 is parallel to the collision side wall portion 11, and the second inner side wall portion 16 is parallel to the collision side wall portion 11, and the first The positions of the inner side wall portion 15 and the second inner side wall portion 16 on the X direction are the same as each other. Further, in the example shown in FIG. 11, the third inner side wall portion 17 is perpendicular to the collision side wall portion 11, and the fourth inner side wall portion 18 is perpendicular to the collision side wall portion 11. Further, in the example shown in FIG. 11, the anti-collision side wall portion 12, a part of the first side wall portion 13, the first inner side wall portion 15, the third inner side wall portion 17, and the collision side wall portion 11 A closed cross section A is formed in a region surrounded by a part of the above, a fourth inner side wall portion 18, a second inner side wall portion 16, and a second side wall portion 14. Further, since the hollow member 10 is formed with a closed cross section A, the hollow member 10 has a first side wall portion 13, a collision side wall portion 11, a third inner side wall portion 17, and a first inner side wall portion 17. A closed cross section B surrounded by the wall portion 15 is formed. Similarly, the hollow member 10 is formed with a closed cross section C surrounded by a second side wall portion 14, a collision side wall portion 11, a fourth inner side wall portion 18, and a second inner side wall portion 16. There is.
[0045]
　In the case of the closed cross-sectional structural material in the example shown in FIG. 11, when a load is input to the collision side wall portion 11 at the time of collision, the ridge line between the collision side wall portion 11 and the collision side wall portion 11 and the first side wall portion 13. Compressive stress acts on the portion 10a and the ridgeline portion 10b between the collision side wall portion 11 and the second side wall portion 14. At this time, since the first inner side wall portion 15 is connected to the first side wall portion 13 and the third inner side wall portion 17 is connected to the collision side wall portion 11, a part 13b of the first side wall portion 13 A moment that tends to fall outward acts on (a portion located on the collision side with respect to the first inner side wall portion 15). Similarly, since the second inner side wall portion 16 is connected to the second side wall portion 14 and the fourth inner side wall portion 18 is connected to the collision side wall portion 11, a part 14b of the second side wall portion 14 is similarly connected. A moment that tends to fall outward acts on (a portion located on the collision side with respect to the second inner side wall portion 16). On the other hand, a moment that tends to fall inward acts on the portion 13a of the first side wall portion 13 located on the anti-collision side with respect to the first inner side wall portion 15. Similarly, a moment that tends to fall inward acts on the portion 14a of the second side wall portion 14 located on the anti-collision side with respect to the second inner side wall portion 16.
[0046]
　Therefore, a moment of collapsing on opposite sides acts on the portion 13a and the portion 13b of the first side wall portion 13, and the first side wall portion 13 is less likely to collapse. Similarly, the second side wall portion 14 is less likely to collapse due to the action of a moment of collapsing on the opposite side of the portion 14a and the portion 14b of the second side wall portion 14. As a result, in the event of a collision, a higher load can be received for a longer period of time, and the maximum load and absorbed energy can be increased.
[0047]
　Under the condition that the length a from the anti-collision side wall portion 12 to the collision side wall portion 11 is constant, the height b and the length a of the third inner side wall portion 17 and the fourth inner side wall portion 18 are The ratio (b / a) is preferably 0.15 to 0.35. Thereby, the maximum load and absorbed energy at the time of collision can be effectively increased. A more desirable lower limit for b / a is 0.17. A more desirable upper limit for b / a is 0.33.
[0048]
　In the example shown in FIG. 12, the inclined wall portion 19 is formed between the collision side wall portion 11 and the first side wall portion 13, and the inclined wall portion 20 between the collision side wall portion 11 and the second side wall portion 14 is formed. Is formed. In this case, the ratio (e1 / a) of the height e1 of the inclined wall portions 19 and 20 to the length a from the anti-collision side wall portion 12 to the collision side wall portion 11 is 0, as in the example shown in FIG. It is desirable that it is 0.05 to 0.20. A more desirable lower limit for e1 / a is 0.08. A more desirable upper limit for e1 / a is 0.17. The ratio (e1 / e2) of the height e1 and the width e2 of the inclined wall portions 19 and 20 is preferably 0.6 to 1.5, and more preferably 0.9 to 1.1. ..
[0049]
　In the example shown in FIG. 13, an inner inclined wall portion 21 is formed between the first inner side wall portion 15 and the third inner side wall portion 17, and the second inner side wall portion 16 and the fourth inner side wall portion 16 are formed. An inner inclined wall portion 22 is formed between the 18 and the inner inclined wall portion 22. In this case, as in the example shown in FIG. 6, the ratio (f1 / a) of the height f1 of the inner inclined wall portions 21 and 22 to the length a from the anti-collision side wall portion 12 to the collision side wall portion 11 is It is desirable that it is 0.05 to 0.20. A more desirable lower limit for f1 / a is 0.08. A more desirable upper limit for f1 / a is 0.17. Further, the ratio (f1 / f2) of the height f1 and the width f2 of the inner inclined wall portions 21 and 22 is preferably 0.6 to 1.5, and more preferably 0.9 to 1.1. preferable.
[0050]
　Further, the closed cross-section structural material is a combination of a structure having the inclined wall portion 19 and the inclined wall portion 20 shown in FIG. 12 and a structure having the inner inclined wall portion 21 and the inner inclined wall portion 22 shown in FIG. You may.
[0051]
　In the example shown in FIG. 14, the collision side wall portion 11 is connected to the collision side end portion of the first side wall portion 13 and the collision side end portion of the second side wall portion 14, and the first collision side wall portion 11a and the second. It has a second collision side wall portion 11b connected to the inner side wall portion 17 of the third and the fourth inner side wall portion 18. The first collision side wall portion 11a and the second collision side wall portion 11b are in a state of being joined to each other by, for example, being welded or integrally molded. By providing such a second collision side wall portion 11b, the bending rigidity of the first collision side wall portion 11a can be increased, and the absorbed energy at the time of collision can be further increased. The second collision side wall portion 11b corresponds to the convex portion top surface 50c of the hat-shaped member 30 in the example shown in FIG.
[0052]
　In the example shown in FIG. 15, one end portion 12a of the anti-collision side wall portion 12 projects outward from the first side wall portion 13 and the other end portion 12b in a cross section with the member longitudinal direction Y as a normal. Projects outward from the hollow member 10 from the second side wall portion 14.
[0053]
　In the examples shown in FIGS. 14 and 15, the inclined wall portions 19 and 20 as shown in FIG. 12 may be provided, and the inner inclined wall portions 21 and 22 as shown in FIG. 13 may be provided. You may be. Further, all the inclined wall portions 19 to 22 may be provided.
Example
[0054]
　An analysis model of a conventional bumper beam and a bumper beam according to the present invention was created, and a load-bearing evaluation simulation of the bumper beam assuming a pole frontal collision was carried out.
[0055]
　Conventional bumper beam analysis models are structure 100 (Comparative Example 1) shown in FIG. 4, structure 200 (Comparative Example 2) shown in FIG. 16, and structure 300 (Comparative Example 3) shown in FIG. The analysis model of Comparative Example 1 has a structure including a closing plate 25 and a hat-shaped member 101. In the analysis model of Comparative Example 2, the closed cross-section structural material of Patent Document 1 is modified into a structure in consideration of productivity, and a recess is provided in the central portion of the top surface 201e of the hat-shaped member 201, and the recess is provided. It is a structure in which a reinforcement 202 is provided inside. In the analysis model of Comparative Example 3, the closed cross-section structural material of Patent Document 2 is modified to have a structure in consideration of productivity, and the widths of the pair of side surfaces 301c and 301d of the hat-shaped member 301 are partially narrowed. The structure is such that the reinforcement 302 is provided so as to cover the narrowed portion.
[0056]
　The bumper beam analysis model according to the present invention has a structure corresponding to the first embodiment shown in FIG. 3 (Examples 1 to 6) and a structure corresponding to the second embodiment shown in FIG. 5 (Embodiment). Examples 7 to 9), a structure corresponding to the third embodiment shown in FIG. 6 (Examples 10 to 12), and a structure corresponding to the fourth embodiment shown in FIG. 7 (Examples 13 to 15). Is. In the analysis models of Examples 1 to 16, the hollow member has a common length a of 60 mm in the X direction and a width c of 60 mm, and as shown in Table 1 below, the ratio b / a described above is 1. It is less than / 2 and d / c is within the range of 5/6 or less. Further, in the analysis model in which the inclined wall portion is provided, both (height of the inclined wall portion e1) / a and (height of the inclined wall portion f1) / a are 1/4 or less. The length of each bumper beam in the longitudinal direction of the member was 1000 mm.
[0057]
　In the load-bearing evaluation simulation, as shown in FIG. 18, a support pole 60 having a diameter of 30 mm is arranged at a position 100 mm inward from both ends of the bumper beam 1 toward the center in the vehicle width direction Y. Further, a pole 61 having a diameter of 254 mm is arranged at the center of the vehicle width direction Y, and is moved by 200 mm in parallel with the vehicle length direction X. The pushing amount (stroke amount) of the pole and the input load at that time were recorded, and the maximum load, that is, the proof stress and the absorbed energy was measured. The absorbed energy is the energy absorbed by the bumper beam while the amount of pushing of the pole is 0 to 100 mm.
[0058]
　Table 1 shows the material strength, plate thickness, and dimensional parameters (b / a, d / c, e1 / a, e2 / a, f1 / a, f2 /) of the parts in Comparative Examples 1 to 3 and Examples 1 to 16. a), the load efficiency obtained by dividing the maximum load of the bumper beam in the simulation by the mass, and the absorbed energy efficiency obtained by dividing the absorbed energy by the mass are shown. The thickness and strength of each component constituting the bumper beam are the same.
[0059]
[table 1]

[0060]
　FIG. 19 shows a load-stroke diagram of Comparative Example 1 and Example 1. Under both conditions, the initial load rises, and after reaching the maximum load, the load decreases. In Comparative Example 1, when the initial load rises, the top surface (collision surface) of the hat-shaped member bends inward, and the pair of side surfaces starts to bend outward. Then, after reaching the maximum load, it begins to buckle in the vehicle height direction, and a pair of side surfaces of the hat-shaped member begins to fall outward. On the other hand, in the first embodiment, when the initial load is raised, only the reinforcement is deformed, and after reaching the maximum load, it begins to buckle in the vehicle height direction, and a pair of side surfaces of the hat-shaped member start to fall inward. Further, FIG. 19 shows that the maximum load and absorbed energy of Example 1 are higher than those of Comparative Example 1. From these results, it was shown that the bumper beam according to the present invention has higher proof stress and higher absorption energy performance than the conventional bumper beam.
[0061]
　Next, the influence of the cross-sectional dimension of the bumper beam according to the present invention on the collision performance was investigated. First, the desirable dimension of the height b of the convex portion was investigated by comparing Examples 1 to 3. When b / a is 0.17 (Example 2), the load efficiency is the highest, and when b / a is 0.33 (Example 1), the absorbed energy efficiency is the highest. From these results, it was shown that b / a is preferably 0.15 to 0.35.
[0062]
　Next, by comparing Examples 1, 4 to 6, the desired dimension of the width d of the convex portion was investigated. It was shown that the smaller the d / c, the higher the load efficiency and the absorbed energy efficiency. In this simulation, from the viewpoint of achieving both load efficiency and absorbed energy efficiency at a high level, it was desirable that d / c be 0.20 or less, but the width c of reinforcement changes. The desired d / c varies depending on.
[0063]
　Next, by comparing Examples 1, 7 to 9, the effect of the presence or absence of the inclined wall portion of the reinforcement was confirmed. Comparing Examples 1 and 7 to 9 from Table 1, it is shown that Examples 7 to 9 have higher absorbed energy efficiency. From these results, it was shown that the collision performance was improved by providing the sloping wall portion in the reinforcement. Further, when e1 / a is 0.08 (Example 7), the load efficiency is the highest, and when e1 / a is 0.17 (Example 8), the absorbed energy efficiency is the highest. From these results, it was shown that e1 / a is preferably 0.05 to 0.20 from the viewpoint of achieving both load efficiency and absorbed energy efficiency at a high level.
[0064]
　Next, by comparing Examples 1, 10 to 12, the effect of the presence or absence of the inclined wall portion between the pair of side surfaces of the convex portion and the top surface of the hat-shaped member was confirmed. Comparing Examples 1 to 10 to 12 from Table 1, it was shown that there are cross-sectional dimensions having high load efficiency and absorbed energy efficiency depending on the height of the inclined wall portion. Further, when f1 / a is 0.08 (Example 10) to 0.17 (Example 11), the effect of improving the load efficiency and the absorbed energy efficiency is recognized. From these results, it was shown that f1 / a is preferably 0.05 to 0.20 from the viewpoint of achieving both load efficiency and absorbed energy efficiency at a high level.
[0065]
　Next, by comparing Examples 1, 13 to 15, the synergistic effect of the inclined wall portion of the reinforcement and the inclined wall portion between the pair of side surfaces of the convex portion and the top surface of the hat-shaped member can be obtained. confirmed. e1 / a was fixed at 0.08, and the effect of f1 / a was confirmed. The absorbed energy efficiency exceeded that of Example 1 under all conditions, and showed a maximum value when f1 / a was 0.17 (Example 14). According to these results, as shown in FIG. 7, a synergistic effect is generated by the slanted wall portion of the reinforcement and the slanted wall portion between the pair of side surfaces of the convex portion and the top surface of the hat-shaped member, and the collision performance is improved. It was shown to improve further.
[0066]
　The analysis model of Example 16 is a model having a structure in which the height e1 and the width e2 of the inclined wall portion of the reinforcement are different, and the width e2 is longer than the height e1. As shown in Table 1, in Example 16, the load efficiency and the absorbed energy efficiency are improved as compared with Comparative Example 1.
[0067]
　FIG. 20 shows load-stroke diagrams of Comparative Examples 2, 3 and 14. FIG. 20 shows that the maximum load and absorbed energy of Example 14 are higher than those of Comparative Examples 2 and 3. From these results, it was shown that the bumper beam according to the present invention has higher proof stress and higher absorption energy performance than the bumper beams of Patent Document 1 and Patent Document 2.
Industrial applicability
[0068]
　INDUSTRIAL APPLICABILITY The present invention can be used as a closed cross-section structural material that is subjected to bending deformation such as a front bumper beam, a rear bumper beam, and a side sill that are attached to a vehicle such as an automobile.
Code description
[0069]
1 Bumper beam　
2 Inner member
3 Outer member
10 Hollow member
11 Collision side wall part
11a First collision side wall part
11b Second collision side wall part
12 Anti-collision side wall part
13 First side wall part
14 Second side wall part
15 First Inner side wall part
16 Second inner side wall part
17 Third inner side wall part
18 Fourth inner side wall part
19 Sloped wall part
20 Sloped wall part
21 Inner sloping wall part
22 Inner sloping wall part
25 Closing plate
30 Hat-shaped member
30a, 30b Flange of hat-shaped member
30c, 30d Side
surface of hat-shaped member 30e Top surface of hat-shaped member
40 Reinforcement
40a, 40b Side
surface of reinforcement 40c Top surface of reinforcement
40d, 40e Ridge between top surface and side surface of reinforcement
40f, 40g Slope
50 convex part
50a, 50b of reinforcement Side
surface of convex part 50c Top surface of convex part
50d, 50e Ridge part
50f, 50g between top surface and side surface of convex part Ridge part
50h, 50i convex between side surface of convex part and top surface of hat-shaped member Slope between the side surface of the part and the top surface of the hat-shaped member
60 Supporting pole
61 Pole
70 Body frame
100 Conventional bumper beam　
101 Hat-shaped member
101a, 101b Hat-shaped member flange
101c, 101d Hat-shaped member side surface
101e Top surface
101f, 101g of hat-shaped member Ridge line portion between top surface and side surface of hat-shaped member
200 Conventional bumper beam　
201 Hat-shaped members
201a, 201b Flange
201c of hat-shaped member, 201d Side
surface of hat-shaped member 201e Top surface of hat-shaped member
202 Reinforcement
300 Conventional bumper beam　
301 Hat-shaped member
301a, 301b Flange
301c of hat-shaped member , 301d Side
surface of hat-shaped member 301e Top surface of hat-shaped member
302 Reinforcement
A to C Closed cross section
a Height of outer member
b Height of convex part
c Width of outer member
d Width of convex part
e1 Height of slope
e2 Slope width
f1 Slope height
f2 Slope width
The scope of the claims
[Claim 1]
　In a cross section of a closed cross section structural material
　whose normal line is the longitudinal direction of the member, a collision side wall portion, an anti-collision side wall portion, a first side wall portion, a second side wall portion, and a first inner side wall portion. A hollow member having a second inner side wall portion, a third inner side wall portion, and a fourth inner side wall portion, and the
　collision side wall portion is a wall portion located on the collision side, and the
　anti- collision side wall portion is provided. The collision side wall portion is a wall portion facing the collision side wall portion and opposite to the collision side, and
　the first side wall portion and the second side wall portion are the end portion of the collision side wall portion and the collision side wall portion. A pair of wall portions connected to an end portion of the anti-collision side wall portion,
　the first inner side wall portion is a wall portion extending inward of the hollow member from the first side wall portion, and
　the second inner wall surface portion . The inner side wall portion is a wall portion extending from the second side wall portion to the inside of the hollow member, and
　the third inner side wall portion is a wall portion connected to the first inner side wall portion and the collision side wall portion. , and the
　said fourth inner wall portion is a wall portion leading to the collision side wall portion and the second inner wall portion.
[Claim 2]
　The closed cross-sectional structural material according to claim 1,
　wherein the collision side wall portion has a first collision side wall portion and a second collision side wall portion, and
　the first collision side wall portion is the said. The second side wall portion is connected to the collision side end portion of the first side wall portion and the collision side end portion of the second side wall portion, and
　the second collision side wall portion is connected to the collision side end portion of the third inner side wall portion. , The fourth inner side wall portion is connected to the collision side end portion, and
　the first collision side wall portion and the second collision side wall portion are joined.
[Claim 3]
　The closed cross-section structural material according to claim 1 or 2,
　wherein the anti-collision side wall portion, a part of the first side wall portion, the first inner side wall portion, and the third inner side wall portion. A closed cross-section space is formed in a region surrounded by a part of the collision side wall portion, the fourth inner side wall portion, the second inner side wall portion, and a part of the second side wall portion. Is formed.
[Claim 4]
　The closed cross-section structural material according to any one of claims 1 to 3,
　wherein the collision side wall portion and the first side wall portion, and the collision side wall portion and the second side wall portion. It has slanted walls formed between them.
[Claim 5]
　The closed cross-section structural material according to claim 4,
　wherein the ratio of the height e1 of the inclined wall portion to the length a from the anti-collision side wall portion to the collision side wall portion is 0.05 to 0.20. Is.
[Claim 6]
　The closed cross-section structural material according to any one of claims 1 to 5,
　wherein the first inner side wall portion and the third inner side wall portion, and the second inner side wall portion and the said It has an inner inclined wall portion formed between the fourth inner side wall portion and the fourth inner side wall portion.
[Claim 7]
　The closed cross-section structural material according to claim 6,
　wherein the ratio of the height f1 of the inner inclined wall portion to the length a from the anti-collision side wall portion to the collision side wall portion is 0.05 to 0. It is 20.
[Claim 8]
　The closed cross-sectional structural material according to any one of claims 1 to 7
　, wherein one end of the anti-collision side wall portion is formed from the first side wall portion in a cross section having a normal in the longitudinal direction of the member. It protrudes outward of the hollow member, and the other end of the anti-collision side wall portion protrudes outward from the second side wall portion.
[Claim 9]
　The closed-section structural material according to any one of claims 1 to 8, further comprising a
　closing plate, a hat-shaped member, and reinforcement, and the
　closing plate is located on the anti-collision side.
　The hat-shaped member includes two flanges joined to the closing plate, a pair of side surfaces extending from the flanges to the collision side, a top surface connected to the pair of side surfaces, and a collision side provided on the top surface. The
　reinforcement has a pair of side surfaces joined to the hat-shaped member and a top surface connected to the pair of side surfaces, and the
　anti-collision side wall portion has a convex portion protruding from the surface. The closing plate and the flange of the hat-shaped member are composed of
　the first side wall portion and the second side wall portion of the pair of side surfaces of the hat-shaped member and the reinforcement of the hat-shaped member. It is composed of the pair of side surfaces, and the
　collision side wall portion is composed of the convex portion of the hat-shaped member and the top surface of the reinforcement.
[Claim 10]
　The vehicle body skeleton
　includes the closed cross-section structural material according to any one of claims 1 to 9, and the
　collision side wall portion is located outside the vehicle with respect to the anti-collision side wall portion.