Shock absorbing member, method for manufacturing shock absorbing member for automobile, and method for manufacturing side member

Abstract

The present invention includes a forming step of forming a part of half of a closed cross-section, in which a part (17, 18) for forming half of the closed cross-section is formed by press-forming a steel sheet blank into a hat-like cross-section having a hat portion (17a, 18a) and a pair of flange portions (17b, 18b). The invention further comprises a body forming step of forming a closed cross-section, in which at least two parts forming half of the closed cross-section are combined and a plurality of closed cross-section forming bodies connected by connecting sections (15) in the longitudinal direction are formed. The cap portion has at least one pair of corner ridges orthogonal to the longitudinal direction. The body forming the closed cross section has connecting sections (15) aligned with the upper or lower surface of the hollow body (14), and the connecting sections (15) are arranged in the longitudinal direction so as to be vertically offset with respect to the center of mass of the hollow body (14). Accordingly, an inexpensive impact absorbing member in which a steel sheet is used as a material can be produced with good productivity.

Description

Technical Field

[0001] The present invention relates to a shock absorbing member for absorbing a shock applied laterally to an automobile body, a method for manufacturing a shock absorbing member of an automobile, and a method for manufacturing a side beam. Background Art

[0002] Conventionally, for example, a reinforcing member for strengthening the side portion of a vehicle body is disclosed in Patent Document 1. The reinforcing member disclosed in this publication is provided inside a side beam of a vehicle body and has a plurality of hollow portions which, when viewed in the vehicle longitudinal direction, have the shape of a closed cross-sectional profile. The plurality of hollow portions are formed by extrusion molding using aluminum alloy as a material and extend in the vehicle longitudinal direction while being aligned in the vehicle width direction. The reinforcing member absorbs a shock applied to the side portion of the vehicle body facing the inside of the vehicle body by squeezing the hollow portions.

[0003] List of Cited Documents

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2018-90021 Summary of the Invention

[0005] A problem with the reinforcing member described in Patent Document 1 is that the manufacturing cost is high because aluminum alloy is more expensive than steel plate and the cost of equipment for extrusion molding is high.

[0006] The present invention aims to produce an inexpensive shock absorbing member made of steel plate with good productivity.

[0007] To achieve this object, a method for manufacturing a shock absorbing member according to one aspect of the present invention includes the following steps:

[0008] Forming a member that constitutes half of a closed cross-sectional profile, the forming step of the half of the closed cross-sectional profile forms a member that constitutes half of the closed cross-sectional profile by pressing a steel plate blank into a member having a hat-shaped cross-section, the member including a hat portion and a pair of flange portions; and

[0009] Forming a structure configured with a closed cross-sectional profile: forming a plurality of structures each configured with a closed cross-sectional profile, the closed cross-sectional profile being joined by combining at least two members and only side-connecting sections in the longitudinal direction, each member being configured to constitute half of the closed cross-sectional profile in such a manner that there are members: each member constitutes half of the closed cross-sectional profile, the half of the closed cross-sectional profile having opposite protruding directions of the hat portions, overlapping and joining the top of the hat portion of one member constituting half of the closed cross-sectional profile with the flange portion of another member constituting half of the closed cross-sectional profile, wherein,

[0010] The hat portion includes at least a pair of corner ridges extending perpendicular to the longitudinal direction.

[0011] The structure configured with a closed cross-sectional profile includes a connecting section aligned with the upper or lower surface of the hollow body.

[0012] The connecting section is arranged in the front-rear direction, and the connecting section is vertically offset from the centroid of the hollow body.

[0013] A method for manufacturing a side beam according to one aspect of the present invention includes the following steps:

[0014] The step of joining an impact absorption member formed by the method for manufacturing an impact absorption member according to any one of claims 1 to 13 to the outer beam; and

[0015] The step of joining the outer beam and the inner beam to which the impact absorption member is joined.

[0016] An impact absorption member according to one aspect of the present invention includes:

[0017] A plurality of structures, each structure configured with a closed cross-sectional profile, each structure being formed by combining at least two members, each member constituting half of the closed cross-sectional profile, each member having a hat portion and a pair of flange portions and being formed with a hat-shaped cross-section, and a plurality of members each constituting half of the closed cross-sectional profile being in a posture where the protruding directions of the hat portions are opposite to each other, wherein,

[0018] The top of the hat portion of one member constituting half of the closed cross-sectional profile is joined to the flange portion of another member constituting half of the closed cross-sectional profile in an overlapping state, and

[0019] The structure configured with a closed cross-sectional profile includes a plurality of hollow bodies and a connecting section that connects the hollow bodies only in the longitudinal direction of the structure configured with the closed cross-sectional profile.

[0020] The hat portion includes at least a pair of corner ridges extending perpendicular to the longitudinal direction, and

[0021] The connecting section is aligned with the upper or lower surface of the hollow body and is arranged in the longitudinal direction, and the connecting section is vertically offset from the centroid of the hollow body.

[0022] According to the present invention, at least two sets of steel plates are manufactured, wherein half of the hollow body (hat portion) and the connecting section (flange portion) are formed by bending and pressing processes, and the steel plates are combined to form an impact absorption member.

[0023] Therefore, the shock-absorbing member can be manufactured by subjecting a steel plate, which is cheaper than an aluminum alloy, to simple bending press working and welding (or riveting or other joining means). Accordingly, an inexpensive shock-absorbing member made of a steel plate can be provided.

[0024] In particular, if there is one die for press-forming the hat part and the flange part, by connecting a plurality of hat parts in a stepped-stone manner in the longitudinal direction via the flange part, a shock-absorbing member of any length can be obtained inexpensively. By simply adding a groove to the flange part, the number of corner ridges of the hollow structure can be increased, thereby increasing the amount of shock energy absorbed. This is because when a load is applied to the hollow structure from the side, the corner ridges are bent sequentially from the front end to the bottom end, thereby absorbing the shock energy.

[0025] Furthermore, according to the present invention, the shock-absorbing member can be attached to the outer side beam using a fixing member, and the outer side beam can be attached to the inner side beam, wherein the outer side beam and the shock-absorbing member are in an integrated form, thereby enabling the effective manufacture of an automotive side beam using the shock-absorbing member formed of a steel plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A perspective view showing a part of a body frame, showing the disassembled side beam.

[0027] Figure 2 A cross-sectional view showing the side beam.

[0028] Figure 3A A perspective view showing the shock-absorbing member.

[0029] Figure 3B A front view showing the shock-absorbing member.

[0030] Figure 4A A perspective view showing a member constituting half of a closed cross-sectional profile.

[0031] Figure 4B A perspective view showing a member constituting half of a closed cross-sectional profile.

[0032] Figure 4C A perspective view showing the structure of a closed cross-sectional profile.

[0033] Figure 5A A perspective view showing a member constituting half of a closed cross-sectional profile having an outer side beam fixing member.

[0034] Figure 5B A perspective view showing a member constituting half of a closed cross-sectional profile having an outer side beam fixing member.

[0035] Figure 6AA front view showing a part of the shock absorption member, showing an example of the formation of the outer beam fixing member.

[0036] Figure 6B A front view showing a part of the shock absorption member, showing an example of the formation of the outer beam fixing member.

[0037] Figure 7 A flowchart showing an example for explaining a method for manufacturing a shock absorption member.

[0038] Figure 8A A front view showing an example for explaining a manufacturing method of the shock absorption member.

[0039] Figure 8B A front view showing an example for explaining a manufacturing method of the shock absorption member.

[0040] Figure 8C A front view showing an example for explaining a manufacturing method of the shock absorption member.

[0041] Figure 8D A front view showing an example for explaining a manufacturing method of the shock absorption member.

[0042] Figure 9 A flowchart showing an example for explaining a method for manufacturing a shock absorption member.

[0043] Figure 10 A perspective view showing an example for explaining a manufacturing method of the shock absorption member.

[0044] Figure 11 A flowchart showing an example for explaining a method for manufacturing a shock absorption member.

[0045] Figure 12 A perspective view showing an example for explaining a manufacturing method of the shock absorption member.

[0046] Figure 13 A flowchart showing an example for explaining a method for manufacturing a shock absorption member.

[0047] Figure 14 A front view showing an example for explaining a manufacturing method of the shock absorption member.

[0048] Figure 15 A flowchart showing an example for explaining a manufacturing method of the side beam.

[0049] Figure 16A A cross-sectional view showing an example for explaining a manufacturing method of the side beam.

[0050] Figure 16BA cross-sectional view showing an example for explaining a manufacturing method of a side beam.

[0051] Figure 16C A cross-sectional view showing an example for explaining a manufacturing method of a side beam.

[0052] Figure 17 A flowchart showing a modified example of a manufacturing method of a side beam.

[0053] Figure 18 A schematic view showing an arrangement of a shock absorbing member.

[0054] Figure 19 A schematic view showing an arrangement of a side beam.

[0055] Figure 20 A cross-sectional view showing a shock absorption principle of a shock absorbing member.

[0056] Figure 21A A cross-sectional view showing a shock absorption principle of a shock absorbing member.

[0057] Figure 21B A cross-sectional view showing a shock absorption principle of a shock absorbing member.

[0058] Figure 22A A perspective view showing another embodiment of a member forming half of a closed cross-sectional profile.

[0059] Figure 22B A perspective view showing another embodiment of a member forming half of a closed cross-sectional profile.

[0060] Figure 23A A perspective view showing another embodiment of a shock absorbing member.

[0061] Figure 23B A perspective view showing another embodiment of a shock absorbing member.

[0062] Figure 24A A cross-sectional view showing a modified example of a closed cross-sectional profile having a corner portion.

[0063] Figure 24B A cross-sectional view showing a modified example of a closed cross-sectional profile having a corner portion.

[0064] Figure 24C A cross-sectional view showing a modified example of a closed cross-sectional profile having a corner portion.

[0065] Figure 24D A cross-sectional view showing a modified example of a closed cross-sectional profile having a corner portion.

[0066] Figure 24E A cross-sectional view showing a modified example of a closed cross-sectional profile having a corner portion is shown.

[0067] Figure 25A A perspective view showing a modified example of a pressed steel plate constituting a shock-absorbing member is shown.

[0068] Figure 25B A perspective view showing a modified example of a shock-absorbing member is shown.

[0069] Figure 26A A perspective view of a shock-absorbing member having a connection section of an external connection type is shown.

[0070] Figure 26B A cross-sectional view showing a part of a shock-absorbing member is shown.

[0071] Figure 26C A cross-sectional view showing a part of a shock-absorbing member is shown.

[0072] Figure 27A A schematic view for explaining a mechanism for axial collapse is shown.

[0073] Figure 27B A schematic view for explaining a mechanism for axial collapse is shown.

[0074] Figure 28A A schematic view for explaining a mechanism for axial collapse is shown.

[0075] Figure 28B A schematic view for explaining a mechanism for axial collapse is shown.

[0076] Figure 29 A graph showing the change in shock-absorbing energy is shown.

[0077] Figure 30 A perspective view showing a modified example of a shock-absorbing member is shown.

[0078] Figure 31 An exploded perspective view of a structure configured with a closed cross-sectional profile, which shows a modified example of a flange portion, is shown.

[0079] Figure 32 A perspective view of a structure configured with a closed cross-sectional profile, which shows a modified example of a flange portion, is shown. DETAILED DESCRIPTION

[0080]

First Embodiment

[0081] Hereinafter, with reference to Figures 1 to 21B Examples of a shock-absorbing member, a method for manufacturing a shock-absorbing member, and a method for manufacturing a side beam according to the present invention will be described in detail.

[0082] Figure 1 The illustrated body frame 1 can be used for an electrically driven vehicle (not shown), and includes an inner front pillar 2, an inner center pillar 3, and side beams 4 at corresponding ends in the vehicle width direction. It should be noted that the outer front pillar and the outer center pillar are not shown in the figure. Figure 1 The side beam 4 is shown in an exploded form.

[0083]

Description of the side beam

[0084] The side beam 4 according to the present embodiment is formed by combining two components into a cylindrical shape extending in the vehicle front-rear direction. An impact absorbing member 6 that cooperates with the side beam 4 to form a side beam structure 5 is accommodated in the side beam 4. The impact absorbing member 6 will be described in detail below.

[0085] The two components constituting the side beam 4 are an inner beam 7 extending in the vehicle front-rear direction on the inner side of the vehicle and an outer beam 8 extending in the vehicle front-rear direction on the outer side of the vehicle. As Figure 2 shown, the inner beam 7 and the outer beam 8 each have a main body 7a, 8a and upper flanges 7b, 8b and lower flanges 7c, 8c for welding. The cross-section of the main bodies 7a, 8a has a concave groove shape, and the upper flanges 7b, 8b and the lower flanges 7c, 8c are integrally formed at the ends of the main bodies 7a, 8a.

[0086] The inner beam 7 is welded to a floor panel (not shown) and a transverse member 11 of the body frame 1 with the opening portion of the main body 7a (which has a cross-section with a concave groove shape) oriented toward the outer side of the vehicle.

[0087] The outer beam 8 is welded to the inner beam 7 in a state where the opening portion of the main body 8a (whose cross-section has a concave groove shape) is oriented toward the inner side of the vehicle. The upper flanges 7b, 8b of the inner beam 7 and the outer beam 8 protrude upward from the upper ends of the main bodies 7a, 8a mounted on the vehicle. The lower flanges 7c, 8c protrude downward from the lower ends of the main bodies 7a, 8a mounted on the vehicle. The upper flanges 7b, 8b and the lower flanges 7c, 8c extend from the front end to the rear end of the inner beam 7 and the outer beam 8. The welding of the inner beam 7 and the outer beam 8 is performed by overlapping the upper flanges 7b, 8b of the inner beam 7 and the outer beam 8 with each other and spot-welding them, and by overlapping the lower flanges 7c, 8c with each other and spot-welding them.

[0088] The impact absorbing member 6 is used to absorb an impact applied to the side beam 4 from the side of the body, and in the present embodiment, it extends from the front end to the rear end in the side beam 4. The impact absorbing member 6 can be provided at a position according to the side impact test results and set to a length according to the side impact test results, so as to be able to reduce costs. The longitudinal direction of the impact absorbing member 6 is the vehicle front-rear direction.

[0089] The holding member 12 for supporting the shock absorbing member 6 in the side beam 4 is welded to the lower end of the shock absorbing member 6. The inner center pillar connecting piece 13 connected to the lower end of the inner center pillar 3 is welded to the upper end of the shock absorbing member 6. Although not shown, the inner center pillar 3 is provided with an outer center pillar and forms a closed cross-sectional profile extending in the vertical direction.

[0090] The holding member 12 extending downward from the shock absorbing member 6 is fixed to the lower flanges 7c, 8c of the lower flanges 7c, 8c by spot welding while being sandwiched between the lower flanges 7c, 8c. In addition, the inner center pillar connecting piece 13 extending upward from the shock absorbing member 6 is fixed to the upper flanges 7b, 8b of the upper flanges 7b, 8b by spot welding while being sandwiched between the upper flanges 7b, 8b. In addition, the inner center pillar connecting piece 13 firmly fixes the lower part of the inner center pillar 3 via the shock absorbing member 6.

[0091]

Description of the shock absorbing member

[0092] As Figure 3A and Figure 3B shown, the shock absorbing member 6 includes: a plurality of hollow bodies 14 arranged at a predetermined interval in the vehicle front-rear direction (from left to right in Figure 3A and Figure 3B ); and a plurality of connecting sections 15 connecting the hollow bodies 14 to each other. Figure 3A A perspective view of the shock absorbing member 6 is shown, and Figure 3B a front view of a part of the shock absorbing member 6 as viewed from the side of the vehicle body is shown.

[0093] The hollow body 14 has a shape that forms a closed cross-sectional profile 16 when viewed from the side of the vehicle body, and is formed in a cylindrical shape extending in the vehicle width direction. The hollow body 14 according to the present embodiment is formed in a prism-shaped hollow shape, and the shape of the closed cross-sectional profile 16 is a parallelogram. Here, for the convenience of identifying the plurality of hollow bodies 14, the hollow bodies 14 are referred to as the first hollow body 14a, the second hollow body 14b, the third hollow body 14c, the fourth hollow body 14d, the fifth hollow body 14e, and the sixth hollow body 14f in the order from front to back in Figure 3A ).

[0094] The connecting section 15 is formed in a plate shape extending in the vehicle front-rear direction and width direction, and connects two adjacent hollow bodies 14 to each other at a position where two adjacent hollow bodies 14 are offset in the vertical direction, that is, at a position where there is a difference in the vertical direction between two adjacent hollow bodies 14. As Figure 3A and Figure 3BAs shown, when three or more hollow bodies 14 are provided in the vehicle front-rear direction and a plurality of connecting sections 15 are provided, the positions of the connecting sections 15 in the up-down direction are alternately distributed along the vehicle front-rear direction. That is to say, the connecting section 15 connecting the first hollow body 14a and the second hollow body 14b connects the upper ends of the first hollow body 14a and the second hollow body 14b to each other, while the connecting section 15 connecting the second hollow body 14b and the third hollow body 14c connects the lower ends of the second hollow body 14b and the third hollow body 14c to each other.

[0095] Figure 3A and Figure 3B The shock-absorbing member 6 shown includes a hollow structure 19, and each hollow structure 19 has two closed cross-sectional profiles 16. The hollow structure 19 is formed to have a pair of parallelograms arranged in a widened shape, and when observed in the cross-sectional direction (vehicle width direction) of the closed cross-sectional profile 16, the distance between the parallelograms gradually increases from the top to the bottom. Hereinafter, such a shape in which a pair of parallelograms or a shape similar to a parallelogram is arranged in a widened shape will be simply referred to as a "widened shape".

[0096] The above-mentioned hollow body 14 and connecting section 15 are formed by combining a first member and a second member that each constitute Figure 4A and Figure 4B half of the closed cross-sectional profiles 17, 18 shown, as Figure 4C shown, to form a structure configuring the closed cross-sectional profile 20. Figure 4A A perspective view showing the first member 17 constituting half of the closed cross-sectional profile is shown. Figure 4B A perspective view showing the second member 18 constituting half of the closed cross-sectional profile is shown. Figure 4C A cross-sectional view showing the structure configuring the closed cross-sectional profile 20 is shown.

[0097] The first member 17 constituting half of the closed cross-sectional profile and the second member 18 constituting half of the closed cross-sectional profile are each formed to have a hat-shaped cross-section by pressing a steel plate, and each has two functional parts.

[0098] The first functional part is the hat parts 17a, 18a, which are in the front-rear direction ( Figure 4A and Figure 4Bin the left - right direction) is located in the central part of the vehicle body and is formed to have a cross - sectional shape of a concave groove. Each of the hat portions 17a and 18a has a flat top 21 and a pair of inclined walls 22 that are connected to the front and rear ends of the top and extend in the up - down direction. The top 21 is formed flat so as to extend in the horizontal direction. The pair of inclined walls 22 constitute the side portions of the hat portions 17a and 18a and are inclined in such a direction that the distance between the inclined walls 22 gradually increases as the distance from the top 21 increases, thus facilitating press forming. The end portions of the inclined walls 22 constitute flange portions that are bent parallel to the top 21 so as to be connected to the second functional member described later. Constituting Figure 4A The inclined wall 22 of the first member 17 that constitutes half of the closed cross - sectional profile shown extends upward from the top 21. Constituting Figure 4B The inclined wall 22 of the second member 18 that constitutes half of the closed cross - sectional profile shown extends downward from the top 21.

[0099] The inclined wall 22 may be provided with a (side beam) fixing member 23, as Figure 5A and Figure 5B shown. The (side beam) fixing member 23 is used to connect the shock - absorbing member 6 to the side beam 8 or the inner beam and is formed in a plate shape that extends from one inclined wall 22 toward the other inclined wall 22 (toward the outside of the closed cross - sectional profile 16).

[0100] There are two methods for mounting the (side beam) fixing member 23 on the inclined wall 22. The first method is to integrally form it with the inclined wall 22, as Figure 5A shown. The second method is to separately form it from the inclined wall 22 and weld it to the inclined wall 22, as Figure 5B shown.

[0101] The second functional member is constituted by a pair of flange portions 17b and 18b (see Figure 4A and Figure 4B ) that project from both ends of the hat portions 17a and 18a in the longitudinal direction of the shock - absorbing member 6. The flange portions 17b and 18b constitute the upper and lower ends of the hollow body 14 and the connecting section 15 and are formed in the shape of a flat plate that extends in the horizontal direction and projects from the tips (lower end or upper end) of the inclined walls 22 in the front - rear direction of the vehicle.

[0102] The first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile may have the same shape or different shapes. For example, depending on the required shock absorption pattern, the number of hat portions on one side may be greater than that on the other side, and the length / thickness / strength of the top 21 / inclined wall 22 may be increased or decreased, or its shape may be changed. Of course, if the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile have the same shape, only one press-forming die is required, which reduces the equipment cost.

[0103] As Figure 4C shown, the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are joined to each other in a state where the protruding directions of the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are opposite to each other in the vertical direction, and the tops 21 of the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile overlap with the ends of the flange portions 17b, 18b on one side. Figure 4C The state is shown where the top 21 of the first member 17 that forms half of the closed cross-sectional profile overlaps with the end of the flange 18b of the second member 18 that forms half of the closed cross-sectional profile on the front side of the vehicle body, and the end of the flange portion 17b of the first member 17 that forms half of the closed cross-sectional profile on the rear side of the vehicle body overlaps with the top 21 of the second member 18 that forms half of the closed cross-sectional profile.

[0104] The first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are joined together by spot welding at the above two overlapping portions. By joining the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile in this way, a structure for configuring the closed cross-sectional profile 20 is formed, such that the inclined walls 22, 22 of the opposing hat portions 17a, 18a of the first and second members that form half of the closed cross-sectional profile portion 17, 18 and the opposing flange portions 17b, 18b constitute the closed cross-sectional profile 16 (hollow body 14).

[0105] The first member 17 that forms half of the closed cross-sectional profile is added to the rear part ( Figure 4C the right end in Figure 4C shown) of the structure of the closed cross-sectional profile 20, and the adjacent hat portions 17a, 18b are combined in such a way that their protruding directions are opposite to each other, thereby forming as Figure 3BThe hollow structure 19 shown. In this case, the top 21 of the hat portion 17a (18a) of one member that forms half of the closed cross-sectional profile 17 (18) overlaps and engages with the flange portion 18a (18b) of the other member that forms half of the closed cross-sectional profile 18 (17). By combining one member that forms half of the closed cross-sectional profile with the structure configuring the closed cross-sectional profile 20 in this way, a second structure configuring the closed cross-sectional profile 20a (see Figure 3B ) is formed. The second structure configuring the closed cross-sectional profile 20a has a hollow structure 19, and the hollow structure 19 has the widened shape as described above.

[0106]

Description of the manufacturing method of the shock absorption member

[0107] As described below, there are four methods of manufacturing the shock absorption member 6 extending in the vehicle front-rear direction using the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile.

[0108] As Figure 7 shown in the flowchart of, the first manufacturing method is executed. First, as shown in step S1 of the flowchart of Figure 7 , the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are each press-formed (see Figure 8A ). In the case where the outer beam fixing member 23 is integrally formed with the first member and the second member, the outer beam fixing member 23 bends along the longitudinal direction of the shock absorption member 6 in this process, and both the first member and the second member form half of the closed cross-sectional profiles 17, 18.

[0109] When welding the outer beam fixing member 23 to the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile, this welding is performed in this step.

[0110] Next, as Figure 8B shown, the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are combined and welded to form a structure configuring the closed cross-sectional profile 20 (step S2). The structure configuring the closed cross-sectional profile (hollow body) 20 is formed in a quantity corresponding to the length of the shock absorption member 6. For example, as Figure 8D shown, the blank can be press-formed to form the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile such that the two hat portions 17a, 18a are continuously aligned, and one of a pair of flange portions 17b, 18b is located on both sides of the common hat portions 17a, 18a. Then, as Figure 8CAs shown, a plurality of structures each forming a closed cross-sectional profile 20 are arranged in the vehicle front-rear direction, and adjacent structures each forming the closed cross-sectional profile 20 are welded to each other. At this time, the tops 21 of the hat portions 17a and 18a overlap with the flange portions 17b and 18b, and the overlapping portions are welded by spot welding (step S3). By joining a plurality of structures each configuring the closed cross-sectional profile 20 in this way, the shock-absorbing member 6 having an elongated shape is completed.

[0111] As Figure 9 shown in the flowchart of Figure 9 The second manufacturing method is performed as shown in step S11 of the flowchart of Figure 8A First, a first member 17 forming half of the closed cross-sectional profile and a second member 18 forming half of the closed cross-sectional profile are respectively formed. The first member 17 forming half of the closed cross-sectional profile and the second member 18 forming half of the closed cross-sectional profile are formed as Figure 8A shown. Next, as shown in the forming step S12 of the first intermediate portion and Figure 10 shown, an upper first intermediate portion 31 and a lower first intermediate portion 32 are formed. At this time, a plurality of first members forming half of the closed cross-sectional profile 17 are arranged in the vehicle front-rear direction, and adjacent first members forming half of the closed cross-sectional profile 17 are welded together to form the upper first intermediate portion 31, and the upper first intermediate portion 31 serves as an intermediate portion. In addition, a plurality of second members forming half of the closed cross-sectional profile 18 are arranged in the vehicle front-rear direction, and adjacent second members forming half of the closed cross-sectional profile 18 are welded together to form the lower first intermediate portion 32 serving as an intermediate portion. The upper first intermediate portion 31 and the lower first intermediate portion 32 do not have a closed cross-sectional profile.

[0112] Then, the upper first intermediate portion 31 and the lower first intermediate portion 32 are combined in an orientation where they face each other along the protruding direction of the hat portion, and the top of the hat portion of one member forming half of the closed cross-sectional profile overlaps and joins with the flange portion of the other member forming half of the closed cross-sectional profile (formation step S13 of the shock-absorbing member). At this time, the top 21 of the hat portion 17a of the upper first intermediate portion 31 of the upper separator is welded to the flange portion 18b of the lower first intermediate portion 32 by spot welding, and the flange portion 17b of the upper first intermediate portion 31 is welded to the top 21 of the hat portion 18a of the lower first intermediate portion 32 by spot welding. In this way, the upper first intermediate portion 31 and the lower first intermediate portion 32 as intermediate portions are joined together to complete the shock-absorbing member 6 having an elongated shape.

[0113] As Figure 11 shown in the flowchart of Figure 11As shown in step S21 of the flowchart, a first member 17 that forms half of the closed cross-sectional profile and a second member 18 that forms half of the closed cross-sectional profile are respectively formed. The first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are formed as shown in Figure 8A Next, as shown in Figure 12 The first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are combined so that the protruding directions of the hat portions face each other, and the top of the hat portion of one member that forms half of the closed cross-sectional profile overlaps and engages with the flange portion of the other member that forms half of the closed cross-sectional profile to form at least two second intermediate portions 33 (formation step S22 of the second intermediate portion). The second intermediate portion 33 has a closed cross-sectional profile. Figure 12 The second intermediate portion 33a and the second intermediate portion 33b are shown. Thereafter, the second intermediate portion 33a and the second intermediate portion 33b are aligned in the front-rear direction and welded to each other (formation step S23 of the shock absorption member). In this way, the second intermediate portion 33a and the second intermediate portion 33b as intermediate portions are joined to each other, thereby completing the shock absorption member 6 having an elongated shape.

[0114] As shown in Figure 13 The fourth manufacturing method is performed as shown in the flowchart. First, as shown in step S31 of the flowchart in Figure 13 A first member 17 that forms half of the closed cross-sectional profile and a second member 18 that forms half of the closed cross-sectional profile are respectively formed. The first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms half of the closed cross-sectional profile are formed as shown in Figure 8A Next, as shown in step S32 of the flowchart and Figure 14 The shock absorption member 6 is formed. At this time, the members that form half of the closed cross-sectional profile of the shock absorption member 6 are combined in a posture where the protruding directions of the adjacent hat portions face each other, and the members that form half of the closed cross-sectional profile are not joined to each other. Then, the top of the hat portion of the member that forms half of the closed cross-sectional profile overlaps and engages with the flange portion of the adjacent member that forms half of the closed cross-sectional profile in an orientation opposite to that of the member that forms half of the closed cross-sectional profile, thereby completing the shock absorption member 6 having an elongated shape. The top of the hat portion of the member that forms half of the closed cross-sectional profile can be joined to the flange portion of the adjacent member, and each flange portion forms half of the closed cross-sectional profile on both sides in an orientation opposite to that of the member that forms half of the closed cross-sectional profile, so that three sheets are joined.

[0115]

Description of the manufacturing method of the side beam

[0116] To manufacture the side beam 4 having the shock absorbing member 6 formed in an elongated shape, the method performs the steps as shown in the Figure 15 flow chart. First, as shown in Figure 16A , the retaining member 12 and the inner center column connecting piece 13 are kept joined to the shock absorbing member 6 (step S41). This welding is performed in this step when the (outer side beam) fixing member 23 is welded to the first member and the second member each forming half of the closed cross-sectional profile 17, 18 of the shock absorbing member 6.

[0117] Next, as shown in Figure 16B , the outer side beam 8 is joined to the shock absorbing member 6 (step S42). This joining is performed by welding the outer side beam 8 to the (outer side beam) fixing member 23. Then, as shown in Figure 16C , the outer side beam 8 joined to the shock absorbing member 6 and the inner side beam 7 are joined together (step S43). This joining is performed by overlapping the upper flange 7b and the lower flange 7c of the inner side beam 7 with the upper flange 8b and the lower flange 8c of the outer side beam 8 and spot welding them together. When this joining is performed, the retaining member 12 and the inner center column connecting piece 13 are sandwiched between the flanges, and these members are also joined to the flanges at the same time. The outer side beam 8 is joined to the inner side beam 7, thereby completing the side beam 4. At this time, the inner center column connecting piece 13 is also joined to the lower end of the inner side beam 7.

[0118]

Description of Another Manufacturing Method of the Side Beam

[0119] The side beam 4 having the shock absorbing member 6 formed in an elongated shape can be manufactured according to the process shown in the Figure 17 flow chart. In the manufacturing method of this side beam 4, first, in step S51, the shock absorbing member 6 is joined to the inner side beam 7. In this case, an inner beam fixing member (not shown) commensurate with the outer side beam fixing member 23 is preset on the shock absorbing member 6 so that the inner beam fixing member is welded to the inner side beam 7 in step S51. Next, in step S52, the outer side beam 8 is welded to the inner side beam 7. In this step S52, the retaining member 12 and the inner center column connecting piece 13 are sandwiched between the upper flange 7b and the lower flange 7c of the inner side beam 7 and the upper flange 8b and the lower flange 8c of the outer side beam 8, and these components are spot welded at the same time. The outer side beam 8 is joined to the inner side beam 7, thereby completing the side beam 4.

[0120] By using this manufacturing method and joining the shock absorbing member 6 to the inner side beam 7 side, it becomes easy to perform positioning so that the load can be transmitted to the rigid member (lateral member) on the floor side.

[0121]

Description of the Beneficial Effects of this Embodiment

[0122] As shown in Figure 18As shown, the shock absorbing member 6 according to the present embodiment includes: at least two hollow bodies 14 arranged at a predetermined interval in the vehicle front-rear direction, wherein the shape of the closed cross-sectional profile 16 extends in the vehicle width direction; and connecting sections 15 (flange sections 17b, 18b and top 21) that connect adjacent hollow bodies 14 to each other at positions offset in the up-down direction (positions with differences in the up-down direction) between adjacent hollow bodies 14. When a plurality of connecting sections 15 are provided in the vehicle front-rear direction, the positions of the connecting sections 15 are alternately distributed in the up-down direction in the vehicle front-rear direction. The shock absorbing member 6 is configured such that the connecting sections 15 (flange sections 17b, 18b) are offset in the up-down direction with respect to the centroid A of the hollow body 14 when viewed from the side, and are away from the centroid A. Therefore, the second moment of area increases compared to the case where the connecting section 15 is located at the same height as the centroid A of the hollow body 14.

[0123] Furthermore, by making the pair of hollow bodies 14, 14 have the above-mentioned widened shape, the strength of the connecting section 15 can be further increased, so that the collision load at the offset position of the connecting section 15 can be firmly absorbed and the shock absorbing member 6 can be squeezed from the outside / end. Since the hollow bodies 14, 14 overlap alternately in the front-rear direction, shock can be absorbed not only in the case of a lateral impact load from the front to the side, but also in the case of an input from any inclination such as upward, downward, forward or backward.

[0124] Furthermore, as Figure 18 shown, since the connecting section 15 is offset in the up-down direction with respect to the centroid A of the hollow body 14, the connecting section 15 is closer to Figure 19 the upper corner portion 41 and the lower corner portion 42 of the inner side beam 7 as shown. The upper corner portion 41 and the lower corner portion 42 of the inner side beam 7 are corner portions, and thus have higher stiffness in the vehicle width direction than other portions compared to the flat portions.

[0125] Therefore, compared to the case where the connecting section 15 is not offset in the up-down direction, during a collision when an impact load is applied to the side beam 4 from the side of the vehicle body, that is, during a side collision, the vertical surface of the inner side beam 7 cannot be bent, and as Figure 20 shown by the dashed line in

[0126] In addition, since the connecting section 15 is offset from the centroid A of the hollow body 14 in the vertical direction, the upper surface / lower surface of the hollow body 14 and the upper and lower connecting sections 15 are closer to the upper and lower corner portions of the inner beam 7. The upper and lower corner portions of the inner beam 7 have high rigidity / strength, and the side impact load is distributed in the vertical direction. Therefore, the inner beam 7 bears the side impact load, suppressing the movement of the shock absorber member 6 toward the vehicle interior (see Figure 21A ). Figure 21A The arrows shown in Figure 21B indicate the amount of movement. As a result, the shock absorber member 6 collapses from the end on the vehicle outer side toward the vehicle interior, which helps increase the amount of impact energy absorbed. In addition, although not shown, the shock absorber member 6 is also close to the lower floor and the upper cross member, further suppressing the movement of the shock absorber member 6 toward the passenger compartment. At the same time, when the connecting section 15 is not offset in the vertical direction but is located at the center as shown in Figure 21B , the inner beam 7 undergoes out-of-plane deformation during a side collision, causing the side surface extending in the vertical direction to deform toward the vehicle interior, as shown by the dashed line in

[0127] . Therefore, the shock absorber member 6 moves toward the inner side of the passenger compartment or tilts within the side beam 4, making the attitude of the shock absorber member 6 unstable and preventing it from advancing from the end on the vehicle outer side toward the vehicle interior and being squeezed.

[0128] Therefore, the minimum unit of the material to be press-formed when manufacturing the shock absorption member 6 is a member that constitutes half of the closed cross-sectional profiles 17 and 18 each having a hat portion 17a, 18a, which makes it easy to press-form a steel sheet. This is because the inclined wall 22 prevents the formation of undercuts during press-forming. In addition, in such press-forming, a component having a shape in which two or more hat portions (for example, two members each constituting half of the closed cross-sectional profile 17) are aligned in the vehicle front-rear direction can be the minimum unit. Further, in the present embodiment, as Figure 3B shown, a plurality of members each constituting half of the closed cross-sectional profile are combined in the vehicle front-rear direction, such that the flange portions 17b, 18b (connection sections 15) are distributed at upper and lower positions, and thus the number of steel sheets at the spot-welded portions of the top 21 and the flange portions 17b, 18b is three. This increases the reliability of spot welding.

[0129] The automotive side beam structure 5 according to the present embodiment includes: an outer beam fixing member 23, as Figure 6A shown, the outer beam fixing member 23 protruding outward from the closed cross-sectional profile 16 of the shock absorption member 6; and an outer beam 8, as Figure 2 shown, the outer beam 8 being joined to the outer beam fixing member 23 while surrounding the shock absorption member 6 from the outside of the vehicle. When the outer beam fixing member 23 extends toward the inside of the closed cross-sectional profile 16 as Figure 6B shown, adjacent outer beam fixing members 23 interfere with each other. Therefore, in this case, in order to avoid interference between the outer beam fixing members 23, the closed cross-sectional profile 16 must be expanded in the vehicle front-rear direction to a dimension that prevents the outer beam fixing members 23 from interfering with each other. This reduces the number of closed cross-sectional profiles 16 in the entire shock absorption member 6 and reduces the amount of energy absorbed by the shock absorption member 6 during a side collision. However, as Figure 6A shown, since the outer beam fixing member 23 in the present embodiment extends outward from the closed cross-sectional profile 16, interference between the outer beam fixing members 23 can be prevented without reducing the amount of energy absorbed by the shock absorption member 6 during a side collision.

[0130] As Figure 2 shown, the automotive side beam structure 5 according to the present embodiment includes: an inner beam 7, which is surrounded by the shock absorption member 6 and disposed on the inner side of the vehicle thereof; an outer beam 8, which surrounds the shock absorption member 6 and is disposed on the outer side of the vehicle thereof; and a holding member 12, which supports the shock absorption member 6 from below. Therefore, the shock absorption member 6 can be held in a stable state within the side beam 4, and thus when an impact is applied to the side beam 4 from the side of the vehicle body, the shock absorption member 6 does not tilt or roll, but rather the upper and lower surfaces of the shock absorption member 6 deform to buckle and absorb the impact.

[0131] In addition, since the shock-absorbing member 6 can be held without being joined to the inner beam 7, manufacturing is facilitated.

[0132] Therefore, a strong side beam structure 5 resistant to side collisions can be easily achieved.

[0133] In the vehicle side beam structure 5 according to the present embodiment, as Figure 2 shown, the inner center pillar 3 is joined to the upper surface of the shock-absorbing member 6. Thus, collision energy can be transferred from the shock-absorbing member 6 to the inner center pillar 3, thereby obtaining an even stronger side beam structure 5 resistant to side collisions.

[0134] The shock-absorbing member 6 according to the present embodiment can be joined to the inner beam 7, although not shown. That is, by firmly joining the shock-absorbing member 6 to the inner beam 7 with an adhesive or the like, a side beam structure 5 with further improved strength can be achieved.

[0135] The shock-absorbing member 6 is manufactured by combining a plurality of members using a manufacturing method of the shock-absorbing member 6, each member constituting half of a closed cross-sectional profile, and each member being a minimum constituent part. The method includes: step S1 of forming a plurality of members, each member constituting half of a closed cross-sectional profile (the first member constitutes half of the closed cross-sectional profile 17, and the second member constitutes half of the closed cross-sectional profile 18); step S2 of forming a structure configured with the closed cross-sectional profile 20; and step S3 of combining a plurality of structures, each structure configured with the closed cross-sectional profile 20 to form a shock-absorbing member 6 having a longer length, as Figure 7 shown in FIG. 8. Therefore, shock-absorbing members 6 of various shapes and lengths can be manufactured. In addition, when there are defective products, replacement can be made based on one member constituting half of the closed cross-sectional profile, thus improving the yield. Further, since the pressing die for forming the steel plate into a predetermined shape can be smaller, the manufacturing cost of the equipment required for production can be kept low.

[0136] As Figures 9 to 12As shown, when adopting the manufacturing method of the shock-absorbing member 6, welding performed during the manufacturing of the shock-absorbing member 6 becomes easier. The manufacturing method includes: a first intermediate portion forming step S11 and a second intermediate portion forming step S21, where intermediate portions (upper first intermediate portion 31, lower first intermediate portion 32, and second intermediate portion 33) are formed by joining a plurality of members each constituting half of a closed cross-sectional profile; and shock-absorbing member forming steps S13 and S23, where a shock-absorbing member 6 with a longer length is formed by joining a plurality of intermediate portions. That is, when manufacturing the shock-absorbing member 6 by arranging a required number of small parts, each small part requires a positioning fixture, which requires a large number of positioning pins. However, when manufacturing the shock-absorbing member 6 by welding a plurality of intermediate portions together, as in this embodiment, the number of positioning fixtures and positioning pins is reduced, making welding easier, as described above.

[0137] As Figure 13 and Figure 14 shown, when adopting the manufacturing method of the shock-absorbing member 6, a shock-absorbing member 6 with a longer length can be formed in the next step after forming members each constituting half of a closed cross-sectional profile. The manufacturing method of the shock-absorbing member 6 includes: step S31 of forming a plurality of members each constituting half of a closed cross-sectional profile (first member 17 constituting half of the closed cross-sectional profile and second member 18 constituting half of the closed cross-sectional profile); and step S32 of forming a shock-absorbing member 6 with a longer length. This eliminates the need for welding equipment (such as welding jigs) for forming intermediate portions and allows the shock-absorbing member 6 to be manufactured at low cost. In addition, since the step of forming intermediate portions is omitted, productivity is improved.

[0138] As Figure 15 shown, the manufacturing method of the side beam 4 according to this embodiment is performed through the following steps: step S42 of joining the shock-absorbing member 6 to the outer beam 8; and step S43 of joining the outer beam 8 to which the shock-absorbing member 6 has been joined to the inner beam 7. Therefore, the inner beam 7 can be pre-welded to the vehicle body frame 1 and supported by the vehicle body frame 1, so that positioning can be easily performed when welding the shock-absorbing member 6 and the outer beam 8 to the inner beam 7. Therefore, the operation of installing the side beam 4 to the vehicle body is facilitated.

[0139]

Second Embodiment

[0140] The shock-absorbing member 6 can be configured as Figures 22A to 24E shown. Figure 22A A perspective view showing the first member 17 constituting half of the closed cross-sectional profile is shown, and Figure 22B a perspective view showing the second member 18 constituting half of the closed cross-sectional profile is shown.Figure 23A A perspective view showing another embodiment of the shock-absorbing member Figure 23B A perspective view showing the upper and lower surfaces of the hollow body and the positions of the connecting sections in the vertical direction Figure 24A An example is shown in which two corner portions are provided on each of the upper and lower sides of the closed cross-sectional profile 16 Figures 24B to 24D An example is shown in which six corner portions are provided on each of the upper and lower sides of the closed cross-sectional profile 16, and Figure 24E An example is shown in which five corner portions are provided on each of the upper and lower sides of the closed cross-sectional profile 16. In Figures 22A to 24E , components that are the same as or commensurate with the components described with reference to Figures 1 to 2 1 are given the same reference numerals, and their detailed descriptions will be appropriately omitted

[0141] In the first member and the second member that respectively form Figure 22A and Figure 22B half of the closed cross-sectional profiles 17 and 18 shown, the concave grooves 52 having two corner portions 51, 51 are formed by press forming between the hat portions 17a, 18a and the flange portions 17b, 18b. The concave grooves 52 having the corner portions 51 are formed by press forming the base ends of the flange portions 17b, 18b (the ends on the hat portion 17a, 18a sides) in the direction in which the heights of the hat portions 17a, 18a increase. The corner portions 51 located on both sides of the concave groove 52 have ridges 53 extending in the vehicle width direction. Hereinafter, the corner portion 51 having the ridge 53 will be simply referred to as the "corner ridge portion 51".

[0142] When the first member 17 forming half of the closed cross-sectional profile and the second member 18 forming half of the closed cross-sectional profile having such a corner ridge portion 51 are combined, two corner ridge portions 51 are provided on each of the upper and lower sides of the closed cross-sectional profile 16, as Figure 23A shown. As Figure 23B shown, the structure of the closed cross-sectional profile 20 configured according to this embodiment has a connecting section 15 aligned with the upper surface 54 or the lower surface 55 of the hollow body 14. The upper surface 54 and the connecting section 15 are offset by a distance A in the vertical direction. The lower surface 55 and the connecting section 15 are offset by a distance B in the vertical direction. The upper surface 54, the lower surface 55, and the connecting section 15 are arranged along the inner beam 7 in the longitudinal direction while being offset in the vertical direction in this way

[0143] The shock absorbing member 6 with the corner ridge 51 added in this way has a greater energy absorption capacity than the shock absorbing member 6 according to the first embodiment. This is because the strength of the corner ridge 51 is high, so the energy required to bend it increases. That is, simply by forming the concave groove 52 during the press forming of the first member 17 that constitutes half of the closed cross-sectional profile and the second member 18 that constitutes half of the closed cross-sectional profile, the amount of energy absorbed by the shock absorbing member 6 can be increased.

[0144] Although not shown, the corner ridge 51 can be provided only on one of the upper side and the lower side of the closed cross-sectional profile 16.

[0145] The corner ridge 51 can be provided on the first member 17 that constitutes half of the closed cross-sectional profile and the second member 18 that constitutes half of the closed cross-sectional profile, as Figures 24A to 2 shown in FIG. 4. That is, as Figure 24A shown, by forming the concave groove 52 into a concave shape and forming the upper side and the lower side such that the closed cross-sectional profile 16 expands in the vertical direction, the corner ridges 51 can be provided at both ends of the upper side and the lower side of the closed cross-sectional profile 16.

[0146] In addition, as Figure 24B shown, by adding two micro-sized second concave grooves 52a and press forming the concave groove 52 such that the closed cross-sectional profile 16 expands in the vertical direction at two positions, the corner ridges 51 can be provided at six positions on each of the upper side and the lower side of the closed cross-sectional profile 16. Through this press forming, the central portions of the upper side and the lower side of the closed cross-sectional profile 16 are recessed inward from the closed cross-sectional profile 16 to have a rectangular cross-section.

[0147] Figure 24C An example is shown in which the upper side and the lower side of the closed cross-sectional profile 16 are formed in a stepped shape, and six corner ridges 51 are provided on each of the upper side and the lower side. The stepped portion 52 is added to Figure 24C one of the concave grooves 52 shown (one concave groove is on the flange portion side), and the upper side and the lower side are formed such that the closed cross-sectional profile 16 expands in the vertical direction.

[0148] Figure 24D An example is shown in which the central portions of the upper side and the lower side of the closed cross-sectional profile 16 protrude outward from the closed cross-sectional profile 16 to have a rectangular cross-section, thereby providing six corner ridges 51 on each of the upper side and the lower side. On the bottom surface of the concave groove 52 shown in Figure 24D , there are smaller micro-sized concave grooves 52c formed by press forming, and the upper side and the lower side are formed such that the closed cross-sectional profile 16 expands in the vertical direction.

[0149] Figure 24E illustrates an example in which the central portions of the upper and lower sides of the closed cross-sectional profile 16 are recessed in a V-shaped cross-section, and five corner ridges 51 are provided on each of the upper and lower sides. The raised portion 52d is formed by press-forming at Figure 24E the center of the bottom surface of the shown concave groove 52 such that this portion is raised. Also in Figure 24E the shown example, the upper and lower sides are also formed such that the closed cross-sectional profile 16 expands in the vertical direction.

[0150]

Third Embodiment

[0151] The shock-absorbing member can be configured as shown in Figure 25A and Figure 25B . In Figure 25A and Figure 25B , components that are the same as or commensurate with the components described with reference to Figures 1 to 2 4 are given the same reference numerals, and their detailed descriptions will be appropriately omitted.

[0152] A member 61 that constitutes half of the closed cross-sectional profile shown in Figure 25A is formed by press-forming a steel plate using a die (not shown) to have a hat-shaped cross-section. That is, the member 61 that constitutes half of the closed cross-sectional profile has flange portions 63 on each side of the hat portion 62. Compared with the first member and the second member that respectively constitute half of the closed cross-sectional profiles 17 and 18 shown in Figure 22A and Figure 22B , the member 61 that constitutes half of the closed cross-sectional profile has a top portion 62a of the hat portion 62 that is longer in the front-rear direction. A recessed portion 64 is formed in the central portion of the top portion 62a in the front-rear direction, where a part of the top portion 62a is recessed toward the inside of the hat portion 62.

[0153] By forming the recessed portion 64 in the top portion 62a of the hat portion 62, stepped portions 65 are formed at two positions on the top portion 62a, and four corner ridges 51 are formed. Thus, six corner ridges 51 are formed on one hat portion 62.

[0154] At the front and rear portions of the top portion 62a that sandwich the recessed portion 64, weakened portions 66 each formed of a through-hole are formed. The weakened portions 66 (the details of which will be described later) are functional components provided for improving the shock-absorbing performance. The weakened portions 66 will be described later.

[0155] In order to form the shock absorbing member 6 using such a member that forms half of the closed cross-sectional profile 61, two members each form half of the closed cross-sectional profile, and half of the closed cross-sectional profile has the same shape as the member 61 that forms half of the closed cross-sectional profile, except that no weakened portion 66 is produced. Then, the members that respectively form half of the closed cross-sectional profile are stacked and joined in positions inverted in the up-down direction, as Figure 25B shown. For convenience, the member that forms half of the closed cross-sectional profile with the weakened portion 66 is referred to as the upper side member that forms half 61a of the closed cross-sectional profile, and the member that forms half of the closed cross-sectional profile without the weakened portion 66 is referred to as the lower side member that forms half 61b of the closed cross-sectional profile. The Figure 25B upper side member that forms half 61a of the closed cross-sectional profile shown is used in a posture where the cap portion 62 protrudes upward, and the lower side member that forms half 61b of the closed cross-sectional profile is used in a posture where the cap portion 62 protrudes downward.

[0156] The rear flange portion 63 of the lower side member that forms half 61b of the closed cross-sectional profile located on the front side and the front flange portion 63 of the lower side member that forms half 61b of the closed cross-sectional profile located on the rear side overlap from below in the recessed portion 64 of the upper side member that forms half 61a of the closed cross-sectional profile. The recessed portion 64 of the lower side member that forms half 61b of the closed cross-sectional profile overlaps with the rear flange portion 63 of the upper side member that forms half 61a of the closed cross-sectional profile located on the front side and the front flange portion 63 of the upper side member that forms half of the closed cross-sectional profile portion 61a located on the rear side. By performing spot welding at such an overlapping portion, the upper side member that forms half 61a of the closed cross-sectional profile and the lower side member that forms half 61b of the closed cross-sectional profile are joined together to form the shock absorbing member 6. In this shock absorbing member 6, the front side hollow body 67 and the rear side hollow body 68 are formed by one upper side member that forms half 61a of the closed cross-sectional profile and two lower side members that respectively form half 61b of the closed cross-sectional profile. The front side hollow body 67 and the rear side hollow body 68 are formed to have the above-mentioned widened shape when viewed in the vehicle width direction.

[0157] In Figure 25B the shock absorbing member 6 shown, the flange portions 63 of the members that respectively form half of the closed cross-sectional profile aligned in the front-rear direction on the opposite upper side and lower side overlap on the bottom surface (the inner surface of the cap portion 62) of the recessed portion 64. The depth H1 of the recessed portion 64 is shallower than the height H2 of the cap portion 62 with respect to the flange portion 63. That is, H1 < H2.

[0158] The recess 64 of the upper side member that forms half 61a of the closed cross-sectional profile constitutes a part of the upper side connection section 69 that connects the upper ends of the front side hollow body 67 and the rear side hollow body 68. The recess 64 of the lower side member that forms half 61b of the closed cross-sectional profile constitutes a part of the lower side connection section 70 that connects the lower ends of the front side hollow body 67 and the rear side hollow body 68.

[0159] Figure 25B The upper side connection section 69 and the lower side connection section 70 of the impact absorbing member shown are arranged by joining the flange portion 63 to the bottom surface of the recess 64, that is, to the inner side of the cap portion 62. Hereinafter, the upper side connection section 69 and the lower side connection section 70 where the flange portion 63 is joined to the inner side of the cap portion 62 will be simply referred to as the "inner side connection type connection section 71".

[0160] Figure 25B The impact absorbing member 6 shown has a Figure 23A and Figure 23B higher impact energy absorption performance than the impact absorbing member 6 shown in which the weakening portion 66 is provided. The reasons are as follows. In the Figure 23A and Figure 23B shown impact absorbing member 6, the connection section 15 corresponds to the above-mentioned recess, as Figure 26A shown. Figure 26A The connection section 15 shown in has flange portions 17b, 18b joined to the outer sides of the cap portions 17a, 18a. Hereinafter, the connection section 15 where the flange portions 17b, 18b are joined to the outer sides of the cap portions 17a, 18a will be simply referred to as the "outer connection type connection section 72".

[0161] In Figure 25B the shown impact absorbing member 6 and Figure 26A the shown impact absorbing member 6, the depth H1 of the recess is shallower than the height H2 of the cap portion with respect to the flange portion (H1 < H2). Therefore, when a partial load of the rod collision acts on the corner ridge portion 51 on the side with the shallower concave groove, as shown by the arrow F in the figure, the load F directly acts on the recess. This load F acts on the Figure 26A outer connection type connection section 72 in the impact absorbing member 6 shown, and acts on the Figure 25B inner side connection type connection section 71 in the impact absorbing member 6 shown.

[0162] When the above load F acts on the outer connection type connection section 72, the flange portions 17b, 18b flip upward from the spot welding portion W toward the top side of the recess, as Figure 26BAs shown. It has been found that if a part of the flange portions 17b, 18b is flipped in this way, the amount of impact energy absorbed is reduced. At the same time, when a partial load of the rod collision acts on one corner ridge portion 51r adjacent to the rear side of the inner-connected connecting portion segment 71 (recessed portion 64) shown in Figure 25B as shown, as shown by the arrow F in the figure, since this corner ridge portion 51r is connected to another corner ridge portion 51f via the recessed portion 64, a reaction force shown by the arrow FH in the figure is generated on the other corner ridge portion 51f. The generation of this reaction force FH prevents the recessed portion 64 from rotating upward and causes the recessed portion 64 to buckle, as Figure 26C shown. Therefore, the impact-absorbing member 6 employing the inner-connected connecting portion segment 71 has high impact energy absorption performance. Therefore, there are cases where the rod collision test can be passed even without providing the weakened portion 66.

[0163] Now, the weakened portion 66 will be described.

[0164] Figure 25A The weakened portion 66 shown in is formed at the outer ends of the front and rear portions of the top 62a of the hat portion 62 in the vehicle width direction, so that the stiffness of these portions is partially reduced. The weakened portion 66 is constituted by a circular hole penetrating the top 62a. The weakened portion 66 is not limited to a through hole, and although not shown, it can be configured by irregularities formed by partially changing the thickness, orifice, concave groove, etc. of the top 62a.

[0165] Figure 25B The impact-absorbing member 6 shown mainly absorbs the impact energy of the rod collision applied from the side of the vehicle body. Here, a case will be described in which the vehicle body slides laterally so that the side of the vehicle body collides with the columnar main body, that is, the case of rod collision (hereinafter simply referred to as "side rod collision"). When an impact force is applied to the impact-absorbing member 6 from the side of the vehicle body (when an axial load is applied along the corner ridge portion 51), the top 62a of the hat portion 62 having the weakened portion 66 deforms, as Figure 27A and Figure 27B shown. Figure 27A and Figure 27B show simplified views of the member 61 constituting half of the closed cross-sectional profile shown in Figure 25A shown. When an impact force is applied to the impact-absorbing member 6 from the side of the vehicle body, the top 62a having the weakened portion 66 deforms, and a lateral force indicated by the arrow F1 is generated on the corner ridge portion 51, resulting in lateral deformation, as Figure 27A and Figure 27B shown. In Figure 27A and Figure 27B , the deformed shape is indicated by a double-dashed line.

[0166] After a side pole collision, the top 62a with the weakened portion 66 first deforms (lateral deformation) such that when viewed from above, the portion of the top 62a with the weakened portion 66 shrinks. That is, the weakened portion 66 serves as a trigger to cause the top 62a to deform first. After the top 62a deforms, the corner ridge 51 connected to the top 62a deforms (longitudinal deformation). If the above-mentioned lateral deformation does not occur, an excessive load acts on the corner ridge 51, causing significant deformation of the top 62a, resulting in partial rupture of the corner ridge 51 to cause longitudinal cracks. As a result, the load that can be received by the shock absorbing member 6 decreases, and the amount of shock energy absorbed decreases.

[0167] As described above, after the top 62a and the corner ridge 51 laterally deform around the weakened portion 66, the corner ridge 51 continues to undergo longitudinal deformation due to the longitudinal force F2 accompanying the side pole collision, as Figure 28A and Figure 28B shown. This longitudinal deformation occurs at a position adjacent to the portion where the above-mentioned lateral deformation occurs on the inner side in the vehicle width direction. In Figure 25B the shock absorbing member 6 shown, four corner ridges 51 are formed on each of the periphery of the front side hollow body 67 and the periphery of the rear side hollow body 68. At each corner ridge 51, longitudinal deformation occurs successively. That is, when an impact force is applied to the shock absorbing member 6 from the side of the vehicle body, the top 62a at the outer end in the vehicle width direction of the shock absorbing member 6 deforms, and the corner ridge 51 starts to deform from the outer end in the vehicle width direction, resulting in multi-stage buckling deformation continuously occurring over the entire length in the vehicle width direction, thereby absorbing shock energy.

[0168] Then, the corner ridges 51 of the front side hollow body 67 and the rear side hollow body 68 are axially compressed in a bellows-like manner, so that the shock energy of the side pole collision is absorbed by the shock absorbing member 6.

[0169] Therefore, according to the present embodiment, a shock absorbing member can be provided that can increase the amount of shock energy absorbed while adopting a structure that promotes axial collapse.

[0170] Compare the magnitude of the shock absorption energy between the shock absorbing member 6 with the weakened portion 66 according to the present embodiment and a comparative shock absorbing member not provided with the weakened portion 66, and obtain Figure 29 the results shown. Figure 29 A graph showing the relationship between the load applied due to a side pole collision and the amount of deformation (stroke) of the shock absorbing member is shown. In Figure 29In the figure, the case where the weakening portion 66 (hole) is not provided is indicated by a dashed line, and the case where the weakening portion 66 (hole) is provided is indicated by a solid line. It can be considered that if the weakening portion 66 (hole) is not provided, an excessive load acts on the ridge line (corner ridge portion 51) that causes longitudinal cracks, thereby reducing the load and impact energy that the impact absorbing member 6 can withstand.

[0171] For repetition, if the weakening portion 66 (hole) is not provided, no lateral force is generated and only a longitudinal force is generated on the corner ridge portion 51, and thus, in the case of a side collision of the rod, a crack (longitudinal crack deformation) is formed in one axial direction (longitudinal direction). At the same time, when the weakening portion 66 according to the present embodiment is provided, the impact force in the side collision of the rod is divided into a longitudinal force and a lateral force, which generates lateral deformation and longitudinal deformation, thereby absorbing the impact. When the corner ridge portion 51 is laterally deformed, the load required to cause longitudinal deformation decreases, but it is not as large as when a longitudinal crack is formed, and longitudinal deformation also occurs. Therefore, the impact absorbing energy (load × stroke) of the side impact of the rod can be increased.

[0172] The weakening portion 66 (hole) shown in the present embodiment is formed of a through hole. The shape of the opening in the weakening portion 66 is a perfect circle. In addition, Figure 25A the shown weakening portion 66 is drilled on the center line extending in the vehicle width direction, at a position equidistant from the front side corner ridge portion 51 and the rear side corner ridge portion 51, and at the front and rear portions sandwiching the recessed portion 64 of the top 62a. The reason for forming the weakening portion 66 in this way is to allow the front side corner ridge portion 51 and the rear side corner ridge portion 51 to buckle simultaneously. The pitch of the buckling of the corner ridge portion 51 caused by the lateral and longitudinal deformations varies in the vehicle width direction according to the diameter of the weakening portion 66, and can be easily adjusted by changing the diameter. The size of the diameter is designed not to block the front side corner ridge portion 51 and the rear side corner ridge portion 51, and to allow insertion of a spot welding gun (not shown) used in an automobile factory. If the weakening portion 66 is formed by a cut that interferes with the edge of the top 62a on the outer side in the vehicle width direction, buckling starts at an early stage of the collision. By increasing the strength of the material of the steel plate forming the member 61 that constitutes half of the closed cross-sectional profile and thus making lateral deformation less likely to occur, the diameter of the weakening portion 66 can be increased or its shape can be changed from a perfect circle to an ellipse or a rectangle elongated in the vehicle width direction.

[0173] The purpose of forming the weakened portion 66 is to trigger buckling in the early stage of a collision. For this purpose, one weakened portion at the end of the shock absorber member on the impact side is sufficient, but when the strength of the material increases, such as in the case of high-strength steel plates, and thus it becomes less likely for buckling to occur, the top 62a can be softened by performing heat treatment or by drilling holes on the center line of the top 62a in the region from the outer end in the vehicle width direction to the inner center portion in the vehicle width direction, thereby adjusting the likelihood of buckling.

[0174]

Fourth Embodiment

[0175] The shock absorber member having the inner-side connection type connection section can be configured as Figure 30 shown. In Figure 30 , components that are the same as or commensurate with the components described with reference to Figure 25A and Figure 25B are given the same reference numerals, and their detailed descriptions will be appropriately omitted.

[0176] The hat portion 62 of the upper-side member that constitutes half 61a of the closed cross-sectional profile and the lower-side member that constitutes half 61b of the closed cross-sectional profile of the shock absorber member 6 shown in Figure 30 do not have the recessed portion 64 shown in Figure 25B .

[0177] The upper-side connection section 69 that connects the upper ends of the front-side hollow body 67 and the rear-side hollow body 68 of the shock absorber member 6 shown in Figure 30 and the lower-side connection section 70 that connects the lower ends of the front-side hollow body 67 and the rear-side hollow body 68 are the "inner-side connection type connection section 115" where the flange portion 63 is joined to the inside of the hat portion 62. Therefore, compared with the case where the connection section 15 in the shock absorber member 6 shown in Figure 3A is an "outer connection type connection section", the shock absorber member 6 shown in Figure 30 has high shock energy absorption performance.

[0178] Figure 25B Or Figure 30The weakened portion 66 of the impact absorbing member 6 shown is formed in the upper member that constitutes half 61a of the closed cross-sectional profile. However, the weakened portion 66 may be provided in the lower member that constitutes half 61b of the closed cross-sectional profile, or may be provided in both the upper member that constitutes half 61a of the closed cross-sectional profile and the lower member that constitutes half 61b of the closed cross-sectional profile. Thus, by providing the weakened portion 66 corresponding to the upper member that constitutes half 61a of the closed cross-sectional profile in the upper member that constitutes half 61a of the closed cross-sectional profile and the lower member that constitutes half 61b of the closed cross-sectional profile, the upper member that constitutes half 61a of the closed cross-sectional profile and the lower member that constitutes half 61b of the closed cross-sectional profile can be press-formed using the same die, thereby improving productivity.

[0179]

Fifth Embodiment

[0180] The connection portion between each member that constitutes half of the closed cross-sectional profile arranged along the longitudinal direction of the vehicle (the longitudinal direction of the impact absorbing member 6) can be configured as shown in Figure 31 and Figure 32 . In Figure 31 and Figure 32 , components that are the same as or commensurate with the components described with reference to Figures 1 to 30 are given the same reference numerals, and their detailed descriptions will be appropriately omitted.

[0181] The flange portions 17b, 18b of the first member 17 that constitutes half of the closed cross-sectional profile shown in Figure 30 and the second member 18 that constitutes half of the closed cross-sectional profile shown in Figure 30 are arranged such that the flange portions adjacent in the longitudinal direction can be combined with each other.

[0182] More specifically, the front ends of the flange portions 17b, 18b located on the front side of the hat portions 17a, 18a are each provided with two notches 121 extending in the longitudinal direction and two tabs 122 adjacent to the notches 121 in the vehicle width direction. The rear ends of the flange portions 17b, 18b located on the rear side of the hat portions 17a, 18a are each provided with two notches 121 extending in the longitudinal direction and two tabs 122 adjacent to the notches 121 in the vehicle width direction. The notches 121 and the tabs 122 are alternately arranged in the vehicle width direction. The dimensions of the notches 121 (width in the longitudinal direction and width in the vehicle width direction) are such that the tabs 122 formed on the other first member or second member that constitutes half of the closed cross-sectional profiles 17, 18 can be inserted therein.

[0183] In order to combine in the longitudinal direction the components that constitute Figure 31Two first members 17, 17 of half of the shown closed cross-sectional profile, tabs 122 formed on the front flange portion 17b of the first member 17 on the rear side constituting half of the closed cross-sectional profile are inserted into notches 121 formed on the rear flange portion 17b of the first member 17 on the front side constituting half of the closed cross-sectional profile. As Figure 32 shown, the tabs 122 on this part to be assembled overlap with the cap portion 18a of the second member 18 constituting half of the closed cross-sectional profile, and are welded to the top 21 of the cap portion 18a by spot welding. In Figure 32 it, the axes of the two electrodes are indicated by the two-dot chain line W when performing spot welding.

[0184] That is, two tabs 122 formed on the rear flange portion 17b of the first member 17 on the front side constituting half of the closed cross-sectional profile and two tabs 122 formed on the front flange portion 17b of the first member 17 on the rear side constituting half of the closed cross-sectional profile are welded to the cap portion 18a of one second member 18 constituting half of the closed cross-sectional profile. By welding together the two first members 17, 17 each constituting half of the closed cross-sectional profile and one second member 18 constituting half of the closed cross-sectional profile in this way, a structure for configuring the closed cross-sectional profile 123 is formed, as Figure 32 shown.

[0185] In Figure 32 the structure of the closed cross-sectional profile 123 shown in the configuration, two hollow bodies 14 are formed on both sides of the cap portion 18a of the second member 18 constituting half of the closed cross-sectional profile. In addition, in this structure for configuring the closed cross-sectional profile 123, a weakened portion 66 is formed in the rear inclined wall 22 of a pair of inclined walls 22, and the rear inclined wall 22 constitutes the cap portion 17a of the first member 17 for constituting half of the closed cross-sectional profile. Although not shown, the weakened portion 66 may also be formed on the upper and lower walls of the hollow body 14, that is, on the flange portions 17b and 18b.

[0186] In Figure 32 the structure of the closed cross-sectional profile 123 shown in the configuration, the joint portion between the two first members constituting half of the closed cross-sectional profile 17 and one second member 18 constituting half of the closed cross-sectional profile is in a two-layer state stacked in the vertical direction (the thickness direction of the flange portions 17b, 18b).

[0187] If the first member 17 that forms half of the closed cross-sectional profile and the second member 18 that forms the other half of the closed cross-sectional profile are shaped to have one or two hat portions 17a, 18a to improve productivity, the number of structures for each configured closed cross-sectional profile 20 required to form the shock absorbing member 6 increases. In this case, the thickness of the connecting portion between the structures of each configured closed cross-sectional profile 20 may become thick, and there is a risk that the strength of this connecting portion becomes greater than the strength of the hollow body 14. However, by forming notches 121 and tabs 122 in the flange portions 17b, 18b, the connecting portion between the structures of the configured closed cross-sectional profile 20 can be made into the two-layer state as described above, and thus the difference in strength distribution between the connecting portion and the hollow body 14 can be eliminated. This makes it possible to prevent the connecting portion from hindering the axial collapse of the hollow body. In addition, in some cases, another plate-like attachment (not shown) may be overlapped on the connecting portion and the three plates may be subjected to sandwich spot welding.

[0188] List of Reference Numerals

[0189] 6: Shock absorbing member;

[0190] 7: Inner beam;

[0191] 8: Outer beam;

[0192] 14: Hollow body;

[0193] 15: Connecting portion segment;

[0194] 16: Closed cross-sectional profile;

[0195] 17: First member forming half of the closed cross-sectional profile;

[0196] 18: Second member forming the other half of the closed cross-sectional profile;

[0197] 17a, 18a, 62: Hat portion;

[0198] 17b, 18b, 63: Flange portion;

[0199] 19: Hollow structure;

[0200] 21, 62a: Top;

[0201] 23: (Outer beam) fixing member;

[0202] 51: Corner portion or corner ridge portion;

[0203] 52: Concave groove;

[0204] 61: Member forming half of the closed cross-sectional profile;

[0205] 64: Depressed portion;

[0206] 66: Weakening part;

[0207] 67: Front side hollow body;

[0208] 68: Rear side hollow body;

[0209] 69: Upper side connecting part section;

[0210] 70: Lower side connecting part section;

[0211] 121: Notch;

[0212] 122: Tab;

[0213] S1, S11, S21, S31: Steps of forming multiple components, each component constituting half of a closed cross-sectional profile;

[0214] S2: Step of forming a structure constituting a closed cross-sectional profile;

[0215] S3: Step of forming an impact absorbing member with a longer length;

[0216] S12, S22: Steps of forming an intermediate part;

[0217] S13, S23: Steps of forming an impact absorbing member with a longer length by joining the intermediate parts together;

[0218] S32: Step of forming an impact absorbing member by connecting the components that constitute half of the closed cross-sectional profile to each other;

[0219] S42: Step of joining an outer beam to the impact absorbing member;

[0220] S43: Step of joining the outer beam and the inner beam together;

[0221] S51: Step of joining the impact absorbing member to the inner beam;

[0222] S52: Step of joining the outer beam to the inner beam.

Claims

1. A method for manufacturing a shock-absorbing member, comprising the following steps: Forming step of a member constituting half of a closed cross-sectional profile: forming a member constituting half of a closed cross-sectional profile by pressing a steel sheet blank into a member having a hat-shaped cross-section, the member having a hat-shaped cross-section including a hat portion and a pair of flange portions; and Forming step of a structure configuring a closed cross-sectional profile: forming a plurality of structures each of which configures a closed cross-sectional profile, by combining at least two members respectively constituting half of a closed cross-sectional profile such that the protruding directions of the hat portions of the plurality of members respectively constituting half of a closed cross-sectional profile are opposite to each other, and overlapping and joining the top of the hat portion of one member constituting half of a closed cross-sectional profile with the flange portion of another member constituting half of a closed cross-sectional profile, to join the plurality of structures each of which configures a closed cross-sectional profile by connecting sections only in the longitudinal direction, wherein, the hat portion includes at least a pair of corner ridges extending perpendicular to the longitudinal direction, the structure configuring a closed cross-sectional profile includes a connecting section aligned with the upper surface or the lower surface of the hollow body, the connecting section is arranged in the front-rear direction, wherein the connecting section is vertically offset from the centroid of the hollow body.

2. The method for manufacturing a shock-absorbing member according to claim 1, wherein, by adding a member constituting half of a closed cross-sectional profile to a structure configuring a closed cross-sectional profile in such a manner that the protruding directions of adjacent hat portions are opposite to each other, and overlapping and joining the top of the hat portion of one member constituting half of a closed cross-sectional profile with the flange portion of another member constituting half of a closed cross-sectional profile, to form a second structure configuring a closed cross-sectional profile, the shock-absorbing member has a hollow structure with a widened shape when observed in the cross-sectional direction.

3. The method for manufacturing a shock-absorbing member according to claim 1, wherein, each of the plurality of members constituting half of a closed cross-sectional profile is formed such that a plurality of hat portions are continuously arranged, wherein the flange portions are common.

4. The method for manufacturing a shock-absorbing member according to claim 1, wherein, the structure configuring a closed cross-sectional profile is formed by changing the longitudinal or transverse dimension, plate thickness, or material of the hat portion or the flange portion of one or two members respectively constituting half of a closed cross-sectional profile for each member constituting half of a closed cross-sectional profile.

5. The method for manufacturing a shock-absorbing member according to claim 1, further comprising the following steps: Forming step of a first intermediate portion: forming an upper shock-absorbing portion and / or a lower shock-absorbing portion continuously arranged via a flange portion as a first intermediate portion by arranging a plurality of hat portions in a row along the longitudinal direction of the shock-absorbing member; and Steps for forming an impact-absorbing member: By combining an upper impact-absorbing portion and a lower impact-absorbing portion in a posture where the protruding directions of the cap portions face each other, overlapping and joining the top of the cap portion of one member that constitutes half of the closed cross-sectional profile with the flange portion of another member that constitutes half of the closed cross-sectional profile, and joining a plurality of members that each constitute half of the closed cross-sectional profile to form a structure in which the closed cross-sectional profile is arranged, an impact-absorbing member with a longer length is formed.

6. The method for manufacturing an impact-absorbing member according to claim 1, further comprising the following steps: Steps for forming a second intermediate portion: By combining a plurality of members that each constitute half of the closed cross-sectional profile in a posture where the protruding directions of the cap portions face each other, and overlapping and joining the top of the cap portion of one member that constitutes half of the closed cross-sectional profile with the flange portion of another member that constitutes half of the closed cross-sectional profile, at least two second intermediate portions are formed; And Steps for forming an impact-absorbing member: By joining the at least two second intermediate portions to form an impact-absorbing member with a longer length, where the top of the cap portion of one second intermediate portion overlaps with the flange portion of another second intermediate portion.

7. The method for manufacturing an impact-absorbing member according to claim 1, wherein, In the step of forming the structure in which the closed cross-sectional profile is arranged, a plurality of members that constitute the impact-absorbing member and each constitute half of the closed cross-sectional profile are combined in a posture where the protruding directions of adjacent cap portions face each other in a state where the plurality of members that each constitute half of the closed cross-sectional profile are not joined to each other, and the top of the cap portion of the member that constitutes half of the closed cross-sectional profile overlaps and is joined with the flange portion of the adjacent member that constitutes half of the closed cross-sectional profile in an opposite posture.

8. The method for manufacturing an impact-absorbing member according to claim 1, wherein, By forming at least one concave groove that is adjacent or not adjacent to the cap portion on at least one or two of the flange portions, a corner ridge portion that extends in the vehicle width direction is added to the structure in which the closed cross-sectional profile is arranged along the hollow structure.

9. The method for manufacturing an impact-absorbing member according to claim 8, wherein, One or more of a stepped portion, a micro-sized concave groove smaller than the concave groove, two or more micro-sized second concave grooves, and a raised portion are added to the concave groove.

10. The method for manufacturing an impact-absorbing member according to claim 1, wherein, The impact-absorbing member includes: a fixing member that protrudes outward from the closed cross-sectional profile and flange portions that face each other, and the fixing member is formed by the inclined walls that face each other of the cap portions of a plurality of members that constitute the impact-absorbing member and each constitute half of the closed cross-sectional profile.

11. The method for manufacturing an impact-absorbing member according to claim 1, wherein, A recessed portion is formed in the central portion in the front-rear direction of the top of the cap portion, and the shape of the recessed portion is such that a part of the top is recessed toward the inside of the cap portion.

12. The method for manufacturing an impact-absorbing member according to claim 1, wherein, A weakened portion with partially reduced stiffness is formed at the outer end of the hat portion in the vehicle width direction.

13. The method for manufacturing a shock absorption member according to claim 1, wherein a notch extending in the longitudinal direction and a tab adjacent to the notch in the vehicle width direction are formed at the end of the flange portion in the front-rear direction, and by inserting the tab formed on the member constituting half of the closed cross-sectional profile of another structure configured with a closed cross-sectional profile into the notch formed in the member constituting half of the closed cross-sectional profile of one structure configured with a closed cross-sectional profile, and joining the notch and the tab, the joint between the two structures respectively configured with closed cross-sectional profiles adjacent to each other in the longitudinal direction is in a two-layer state.

14. A method for manufacturing a side beam, comprising the steps of: joining a shock absorption member to an outer side beam, the shock absorption member being formed by the method according to any one of claims 1 to 13; and joining the outer side beam and an inner side beam, the shock absorption member being joined to the outer side beam.

15. A method for manufacturing a side beam, comprising the steps of: joining a shock absorption member to an inner side beam, the shock absorption member being formed by the method according to any one of claims 1 to 13; and joining the inner side beam and an outer side beam, the shock absorption member being joined to the inner side beam.

16. A shock absorption member, comprising: a plurality of structures, each structure being configured as a closed cross-sectional profile, each structure being formed by combining at least two members, each member constituting half of the closed cross-sectional profile, each member having a hat portion and a pair of flange portions and being formed with a hat-shaped cross-section, and a plurality of members each constituting half of the closed cross-sectional profile being in a posture where the protruding directions of the hat portions are opposite to each other, wherein the top of the hat portion of one member constituting half of the closed cross-sectional profile is joined to the flange portion of another member constituting half of the closed cross-sectional profile in an overlapping state, and the structure configured as a closed cross-sectional profile includes: a plurality of hollow bodies and connecting sections, the connecting sections connecting the hollow bodies only in the longitudinal direction of the structure configured with the closed cross-sectional profile, the hat portion includes at least a pair of corner ridges extending perpendicular to the longitudinal direction, and the connecting sections and the upper surface or the lower surface of the hollow body are arranged in a row and arranged in the longitudinal direction, wherein the connecting sections are offset from the centroid of the hollow body in the up-down direction.

17. The shock absorption member according to claim 16, wherein a recessed portion is formed in the central portion in the longitudinal direction of the top of the hat portion, and the shape of the recessed portion is such that a part of the top is recessed toward the inside of the hat portion.

18. The shock absorption member according to claim 16, wherein a weakened portion with partially reduced stiffness is formed at the outer end of the hat portion in the vehicle width direction.

19. The shock absorption member according to claim 16, wherein A notch extending in the longitudinal direction and a tab adjacent to the notch in the vehicle width direction are formed at the longitudinal end of the flange portion, and by inserting a tab formed on a member that constitutes half of the closed cross-sectional shape of one structure configuring the closed cross-sectional profile into a notch formed on a member that constitutes half of the closed cross-sectional profile of another structure configuring the closed cross-sectional profile, and combining the notch and the tab, the joint between two structures respectively configuring the closed cross-sectional profile adjacent to each other in the longitudinal direction is in a two-layer state stacked in the thickness direction of the flange portion.

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