Side beam structure and underbody structure of automobile

Abstract

Provided are a side beam structure and a lower structure of an automobile, which can further improve the degree of freedom in setting the shape of an impact absorbing member and achieve higher side impact resistance. A vehicle body (1) includes a side beam (15) and an impact absorbing member (30). The impact absorbing member (30) is formed of a plurality of members (31, 32). The impact absorbing member (30) includes a hat-shaped portion (40) having a first top plate portion (41) and a pair of longitudinal wall portions (45, 46), and a second top plate portion (42) connecting the pair of longitudinal wall portions (45, 46) to each other. The second top plate portion (42) divides an inner side space of the hat-shaped portion (40) in a width direction (X), thereby forming a first closed cross section portion (61) containing the first top plate portion (41) and a second closed cross section portion (62) adjacent to the first closed cross section portion (61) in the width direction X. The impact absorbing member (30) is separate from a side beam outer member (21), or the impact absorbing member (30) is in contact with the side beam outer member (21) without being joined to the side beam outer member (21).

Description

Technical Field

[0001] This disclosure relates to side beam construction and the underbody construction of automobiles. Background Technology

[0002] A passenger car body, as a type of vehicle, typically includes: a center pillar, which is arranged vertically along the body; and side beams, which are connected to the lower part of the center pillar and arranged longitudinally along the body (for example, see Patent Documents 1-3). In the event of a side collision, the center pillar and side beams cooperate to bear the impact load, thereby absorbing the impact and protecting the occupants inside the passenger compartment.

[0003] In Patent Document 1, a reinforcing member is disposed within the side beam to effectively absorb the impact energy during a side collision. This reinforcing member includes: a pair of transverse walls extending in the vehicle width direction and disposed separately from each other in the vehicle vertical direction; a pair of longitudinal walls disposed separately from each other in the vehicle width direction and connected to the pair of transverse walls; and a plurality of intermediate longitudinal walls disposed between the pair of longitudinal walls in the vehicle width direction and connected to the pair of transverse walls. This reinforcing member is a one-piece molded article based on an extruded aluminum profile.

[0004] Patent Document 2 describes a vehicle side beam comprising: a side beam frame formed including a hollow portion; a first reinforcing frame disposed in the hollow portion and joined to the side beam frame; and a second reinforcing frame disposed in the hollow portion and joined to the first reinforcing frame and the side beam frame. The first and second reinforcing frames are cap members, arranged sequentially from the inner side in the vehicle width direction. The second reinforcing frame is joined to a second side beam frame on the outer side in the vehicle width direction within the side beam frame.

[0005] Patent Document 3 describes a vehicle side beam comprising: an inner panel; an outer panel joined to the inner panel; and a first buffer member disposed between these panels and forming a plurality of closed sections arranged in the width direction of the side beam. The first buffer member comprises a body formed by bending a single sheet metal and at least one partition wall member connecting the two sides of the body. The body is formed in a cap shape. The top plate of the body is joined to the outer panel.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2021-066315

[0009] Patent Document 2: Japanese Patent Publication No. 2024-524258

[0010] Patent Document 3: Japanese Patent Publication No. 2023-541988 Summary of the Invention

[0011] The problem the invention aims to solve

[0012] In battery electric vehicles (BEVs), the battery that drives the electric motor is located between the left and right side beams under the vehicle body. The battery is housed in a battery pack. Regarding side impacts, there is a growing demand for higher crash safety performance, considering both battery protection and the increased collision energy due to recent increases in battery weight. This demand for higher crash safety performance is not limited to electric vehicles; it also applies to vehicles that directly transmit the output of an internal combustion engine to the wheels. Therefore, it is preferable that the reinforcing members (impact-absorbing members) within the side beams have a more suitable shape depending on the vehicle type, etc.

[0013] However, the reinforcing member described in Patent Document 1 is a one-piece molded product based on extrusion molding, thus offering limited freedom in shape design. Furthermore, in Patent Documents 2 and 3, the impact-absorbing member disposed within the side beam is joined to the outer member of the side beam. As a result, in a side impact, the impact-absorbing member is prone to deformation along with the deformation of the outer member of the side beam. Therefore, there is a possibility that the impact-absorbing member may not undergo the deformation intended in its design, leaving room for improvement in side impact resistance.

[0014] In view of the above problems, one of the objectives of this disclosure is to provide a side beam structure and a vehicle underbody structure that can further improve the freedom of shape setting of the impact absorbing member and achieve higher side impact resistance performance.

[0015] Solution for solving the problem

[0016] The subject of this disclosure is the following side beam construction and the lower structure of the automobile.

[0017] (1) A side beam structure, wherein the side beam structure comprises: a side beam including an outer side beam member and an inner side beam member disposed at a position inside the vehicle width direction relative to the outer side beam member, extending in the vehicle longitudinal direction and forming a closed cross-sectional space in a cross section orthogonal to the vehicle longitudinal direction; and an impact absorbing member formed of a plurality of members, the impact absorbing member including in the cross section: a hat-shaped portion having a first top plate portion extending in the vehicle height direction and two ends of the first top plate portion extending along the vehicle width direction in the vehicle height direction. The first roof has a pair of longitudinal wall portions and a second roof plate portion, which is disposed off the ground from the first roof plate portion in the vehicle width direction and connects the pair of longitudinal wall portions to each other. The second roof plate portion divides the inner space of the hat-shaped portion in the vehicle width direction, thereby forming a first closed section portion including the first roof plate portion and a second closed section portion adjacent to the first closed section portion in the vehicle width direction. The impact absorbing member is separate from the outer member of the side beam, or the impact absorbing member contacts the outer member of the side beam without being engaged with it.

[0018] (2) According to the side beam structure described in (1), the impact absorbing member is formed by combining a first cap member and a second cap member, the top plate portion of the first cap member forms the first top plate portion, the top plate portion of the second cap member forms the second top plate portion, and a pair of first portions of a pair of longitudinal wall portions of the first cap member and a pair of second portions of a pair of longitudinal wall portions of the second cap member cooperate to form a pair of longitudinal wall portions.

[0019] (3) According to the side beam structure described in (2), wherein the Vickers hardness of the first cap member is lower than that of the second cap member.

[0020] (4) According to the side beam structure described in (2), wherein the Vickers hardness of the first cap member is higher than that of the second cap member.

[0021] (5) The side beam construction according to any one of (2) to (4), wherein the thickness of the first cap member is smaller than the thickness of the second cap member.

[0022] (6) The side beam construction according to any one of (1) to (4), wherein the thickness of the first cap member is greater than the thickness of the second cap member.

[0023] (7) The side beam construction according to any one of (2) to (6), wherein, for the Vickers hardness HV1 and plate thickness t1 at the first cap member, and for the Vickers hardness HV2 and plate thickness t2 at the second cap member, 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, and HV1×t1<HV2×t2.

[0024] (8) According to the side beam structure described in (1), wherein the impact absorbing member includes a cap member forming the cap-shaped portion and a top plate member forming the second top plate portion.

[0025] (9) According to the side beam structure described in (8), for the Vickers hardness HV2 and plate thickness t2 at the cap member, and for the Vickers hardness HV1 and plate thickness t1 at the top plate member, 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, and HV1×t1<HV2×t2.

[0026] (10) The side beam construction according to any one of (1) to (9), wherein the second top plate portion of the impact absorbing member has a shape that protrudes toward the first top plate portion in the cross section.

[0027] (11) The side beam construction according to any one of (1) to (10), wherein the impact absorbing member is made of steel plate.

[0028] (12) The side beam construction according to any one of (1) to (11), wherein the cap-shaped portion includes a pair of flanges extending from a pair of said longitudinal wall portions, the pair of said flanges engaging the inner member of the side beam.

[0029] (13) The side beam construction according to any one of (1) to (12), wherein a reinforcing rib is formed in the impact absorbing member.

[0030] (14) The side beam construction according to any one of (1) to (13), wherein the impact absorbing member is supported on the side beam in the closed cross-section space, or the impact absorbing member is disposed on the side of the side beam in the vehicle width direction.

[0031] (15) The side beam construction according to any one of (2) to (7), wherein the first cap member includes a pair of first flanges, a pair of first longitudinal wall portions extending from the pair of first flanges, and a first top plate portion connecting the pair of first longitudinal wall portions; the second cap member includes a pair of second flanges, a pair of second longitudinal wall portions extending from the pair of second flanges, and a second top plate portion connecting the pair of second longitudinal wall portions and engaging with the pair of first flanges.

[0032] (16) The side beam construction according to any one of (2) to (7) and (15), wherein at least one of the cap members further includes a reinforcing member.

[0033] (17) The side beam construction according to any one of (2) to (7) and (15) to (16), wherein the impact absorbing member further has an nth cap member formed in the cross section in the shape of a cap, wherein n is a natural number of 3 or more, the nth cap member comprising a pair of nth flanges, a pair of nth longitudinal wall portions extending from the pair of nth flanges, and an nth top plate portion connecting the pair of nth longitudinal wall portions, each of the cap members being arranged along the vehicle width direction, wherein in the adjacent cap members, the top plate portion is engaged with the pair of flanges.

[0034] (18) The side beam construction according to any one of (1) to (17), wherein the impact absorbing member is made of steel plate.

[0035] (19) A lower structure of an automobile, wherein the lower structure of the automobile includes a side beam structure as described in any one of (1) to (18), the side beams being provided separately in a pair in the vehicle width direction, the lower structure of the automobile further including a plurality of crossbeams disposed between the pair of side beams and extending in the vehicle width direction, the impact absorbing member being disposed inside each of the pair of side beams or inside the vehicle width direction.

[0036] (20) The lower structure of the vehicle according to (19) further includes a battery housing disposed below the crossbeam and housing the battery.

[0037] The effects of the invention

[0038] According to this disclosure, the degree of freedom in setting the shape of the impact-absorbing component can be further improved, and higher side impact resistance performance can be achieved. Attached Figure Description

[0039] Figure 1 This is an exploded perspective view showing a portion of the body of a car, including the lower structure, which includes the side beam structure of the first embodiment of this disclosure.

[0040] Figure 2 It is along the lower structure Figure 1 A sectional view along line II-II.

[0041] Figure 3 This is a schematic cross-sectional view showing the main parts of a first variation of the first embodiment of the present disclosure.

[0042] Figure 4 This is a schematic perspective view showing the main parts of a third variation of the first embodiment of the present disclosure.

[0043] Figure 5 This is a cross-sectional view showing the main part of the fourth variation of the first embodiment of this disclosure.

[0044] Figure 6 This is a cross-sectional view showing the main part of the fifth modification of the first embodiment of this disclosure.

[0045] Figure 7 This is a cross-sectional view showing the main part of one of the other variations of the first embodiment of this disclosure.

[0046] Figure 8 This is an exploded perspective view showing a portion of the body of a car, including the lower structure, which includes the side beam structure of the second embodiment of this disclosure.

[0047] Figure 9 It is along the lower structure Figure 8 A cross-sectional view of the IX-IX line.

[0048] Figure 10 This is a schematic cross-sectional view showing the main parts of the first variation of the second embodiment of the present disclosure.

[0049] Figure 11 This is a schematic cross-sectional view showing the main parts of a second variation of the second embodiment of the present disclosure.

[0050] Figure 12 This is a schematic cross-sectional view showing the main parts of a third variation of the second embodiment of the present disclosure.

[0051] Figure 13 This is a schematic cross-sectional view showing the main parts of the fourth variation of the second embodiment of the present disclosure.

[0052] Figure 14 This is a schematic cross-sectional view showing the main parts of the fifth variation of the second embodiment of the present disclosure.

[0053] Figure 15 The accompanying drawings are for a fifth variation of the second embodiment.

[0054] Figure 16 This is a schematic cross-sectional view showing the main parts of the sixth variation of the second embodiment of the present disclosure.

[0055] Figure 17 This is a diagram showing a modification of the sixth modification of the second embodiment.

[0056] Figure 18 This is a schematic cross-sectional view showing the main parts of the seventh variation of the second embodiment of the present disclosure.

[0057] Figure 19 This is a schematic cross-sectional view showing the main parts of the eighth variation of the second embodiment of the present disclosure.

[0058] Figure 20 This is a schematic cross-sectional view showing the main parts of the ninth variation of the second embodiment of the present disclosure.

[0059] Figure 21 This is a schematic cross-sectional view showing the main parts of the 10th variation of the second embodiment of the present disclosure.

[0060] Figure 22 This is a schematic cross-sectional view showing the main parts of the 11th variation of the second embodiment of the present disclosure.

[0061] Figure 23 This is a diagram illustrating a modified example of the 11th modification of the second embodiment.

[0062] Figure 24 This is a schematic cross-sectional view showing the main part of the 12th variation of the second embodiment of the present disclosure.

[0063] Figure 25 This is a schematic cross-sectional view showing the main part of the 14th variation of the second embodiment of the present disclosure.

[0064] Figure 26 This is a schematic perspective view showing the main parts of the 14th variation of the second embodiment of the present disclosure. Detailed Implementation

[0065] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In this embodiment, a vehicle body structure applied to an automobile will be described.

[0066] [First Embodiment]

[0067] (Body)

[0068] Figure 1 This is an exploded perspective view showing a portion of the car body 1, including the lower structure 2, which includes the side beam structure 14 of the first embodiment of this disclosure. Figure 2 It is along the lower structure 2 Figure 1 A sectional view along line II-II. Furthermore... Figure 2This diagram shows the battery casing 100 fixed to the lower structure 2; the inner side of the cross-section is omitted. In this specification, the direction along the travel direction of the vehicle body 1 (vehicle) is defined as the front-rear direction Y, the travel direction of the vehicle body is defined as the front, and the opposite side is defined as the rear. The vertical direction of the vehicle body is defined as the height direction Z, and the direction orthogonal to the front-rear direction Y and the height direction Z is defined as the width direction X. Furthermore, in the width direction X, the direction furthest from the center of the vehicle body 1 is defined as the outer side, and the opposite direction is defined as the inner side.

[0069] like Figure 1 and Figure 2 As shown, the vehicle body 1 is a part of the vehicle, and the vehicle can be an automobile. As an example of an automobile, a passenger car can be mentioned. As examples of the aforementioned passenger cars, sedan-type passenger cars, coupe-type passenger cars, hatchback-type passenger cars, minivan-type passenger cars, and SUV (Sport Utility Vehicle)-type passenger cars can be mentioned. Furthermore, the vehicle can be, for example, an electric vehicle (Battery Electric Vehicle) or a hybrid vehicle (HV) including a plug-in hybrid, capable of driving the drive wheels using electricity from a battery 101 located in the lower part of the vehicle body 1.

[0070] The vehicle body 1 includes a frame 10 and a battery casing 100.

[0071] The frame 10 has a front column 11, a top column 12, a middle column 13, a side beam structure 14 including side beams 15, floor beams 16 and 17, and a floor panel 18.

[0072] The front pillar 11, the top pillar 12, the middle pillar 13, and the side beam structure 14 including the side beam 15 are provided separately in the width direction X.

[0073] The front pillar 11 has: a top pillar member 11a, which extends upward and rearward, and is joined to the top pillar 12; and a bottom pillar member 11b, which is disposed below the top pillar member 11a.

[0074] The top pillar 12 is located on the roof of the vehicle body 1 and extends rearward from the pillar member 11a.

[0075] The central column 13 is configured along the height direction Z, connecting the top column 12 and the side beam 15.

[0076] The side beam 15 is located at the lower part of the outer portion of the vehicle body 1 in the width direction X. The side beam 15 is connected to the lower part of the center pillar 13 and is arranged along the longitudinal direction Y of the vehicle body 1. The side beam 15 forms a closed section shape in a section orthogonal to the longitudinal direction Y.

[0077] Floor beams 16 and 17 are members extending in the width direction X, positioned between and connecting a pair of left and right side beams 15 and 15. Floor beams 16 and 17 are located on the front seat side of the passenger compartment (cabin) formed by the vehicle body 1. Floor beams 16 and 17 are separately positioned in the front-rear direction Y, with floor beam 17 positioned behind floor beam 16. Each floor beam 16 and 17 has a cap-shaped cross-section orthogonal to the width direction X, which, in conjunction with the floor panel 18, forms a closed cross-section. The floor panel 18 forms the bottom of the passenger compartment of the vehicle body 1 and is fixed to floor beams 16 and 17.

[0078] Slide rails (not shown) are installed on floor beams 16 and 17. The slide rails support the seats (not shown) for occupants.

[0079] A plate-shaped floor panel 18 is provided below the floor beams 16 and 17. A battery housing 100 is provided below the floor panel 18. The battery housing 100 houses a battery 101 containing batteries such as lithium-ion batteries.

[0080] To protect the battery 101 in a side collision (pole-side collision) with a utility pole, the side beam 15 is positioned outward of the battery 101 in the width direction X. The side beam 15 extends in the front-rear direction Y. The battery housing 100 is fixed to the side beam 15. In this embodiment, the width direction end 100a of the battery housing 100 is fixed to, for example, the lower wall 224 of the side beam inner member 22 (described later) of the side beam 15. A side wall 100b, for example, rising upward from the width direction end 100a, is formed as a protective wall for the battery 101 in the middle portion of the battery housing 100 in the width direction X. The battery 101 is positioned inward of the side wall 100b in the width direction X. A gap A is formed between the side wall 100b and the side beam inner member 22. The gap A varies depending on the vehicle type, but can be exemplified as a value of several millimeters to tens of millimeters.

[0081] (Side beam construction)

[0082] When describing the side beam structure 14, unless otherwise specified, the structure at the section orthogonal to the front-rear direction Y will be described. A pair of side beam structures 14 are provided separately in the width direction X.

[0083] Each side beam structure 14 includes the aforementioned side beam 15 and impact-absorbing member 30.

[0084] The side beam 15 includes an outer side beam member 21 and an inner side beam member 22 disposed inside the outer side beam member 21 in the width direction X.

[0085] The outer member 21 and the inner member 22 of the side beam are respectively formed into a cap shape, which cooperate to form a closed section space 23 at the side beam 15.

[0086] The outer member 21 of the side beam has a shape that opens inward in the width direction X, and the inner member 22 of the side beam has a shape that opens outward in the width direction X. The outer member 21 and the inner member 22 of the side beam are fixed together by welding or fastening means with their flanges 211, 221 and 215, 225 abutting against each other. In this embodiment, the outer member 21 and the inner member 22 of the side beam are joined together, for example, by welding. Various welding methods can be used, such as spot welding, TIG welding, arc welding, laser welding, and plasma welding. The same applies to welding methods used when joining other parts.

[0087] More specifically, the outer member 21 of the side beam has an upper flange 211, an upper wall 212 extending outward from the upper flange 211 in the width direction X, a side wall 213 extending downward from the upper wall 212, a lower wall 214 extending inward from the side wall 213 in the width direction X, and a lower flange 215 extending downward from the lower wall 214.

[0088] The inner member 22 of the side beam has an upper flange 221, an upper wall 222 extending inward from the upper flange 221 in the width direction X, a side wall 223 extending downward from the upper wall 222 and joining the floor beams 16 and 17, a lower wall 224 extending outward from the side wall 223 in the width direction X, and a lower flange 225 extending downward from the lower wall 224.

[0089] The upper flanges 211 and 221 are joined together by the joining method described above. Similarly, the lower flanges 215 and 225 are joined together by the joining method described above.

[0090] The upper wall 212 and lower wall 214 of the outer member 21 of the side beam are inclined such that their relative spacing in the height direction Z narrows as they extend outward toward the width direction X. In this embodiment, the inclination angles of the upper wall 212 and lower wall 214 relative to the horizontal plane are larger than the inclination angles of the upper wall 222 and lower wall 224 of the inner member 22 of the side beam relative to the horizontal plane. Furthermore, in this embodiment, the length of the outer member 21 in the width direction X is larger than the length of the inner member 22 in the width direction X. With this structure, the space on the side of the outer member 21 of the side beam and the inner member 22 of the side beam is further increased in the closed section space 23. Additionally, in this embodiment, the length of the side wall 213 of the outer member 21 in the height direction Z is smaller than the length of the side wall 223 of the inner member 22 in the height direction Z. With this structure, the side beam 15 forms a closed section space 23 that protrudes outward toward the width direction X.

[0091] In addition, the side beam 15 can also be symmetrical in the width direction X, and the specific shape is not limited.

[0092] (Main structure of impact absorbing components)

[0093] The impact absorbing member 30 works in conjunction with the side beam 15 to plastically deform during a side collision, thereby absorbing the impact energy of the side collision.

[0094] The impact-absorbing member 30 is formed by multiple members (in this embodiment, the first cap member 31 and the second cap member 32).

[0095] The impact-absorbing member 30 includes: a cap-shaped portion 40 having a first top plate portion 41 extending in the height direction Z and a pair of longitudinal wall portions 45, 46 extending from both ends of the first top plate portion 41 in the height direction Z along the width direction X; and a second top plate portion 42, which is separately disposed from the first top plate portion 41 in the width direction X, connecting the pair of longitudinal wall portions 45, 46 to each other.

[0096] The second top plate portion 42 divides the inner space of the hat-shaped portion 40 in the width direction X, thereby forming a first closed section portion 61 including the first top plate portion 41 and a second closed section portion 62 adjacent to the first closed section portion 61 in the width direction X. The impact absorbing member 30 is separated from the outer member 21 of the side beam, or the impact absorbing member 30 is in contact with the outer member 21 of the side beam without being engaged with it.

[0097] (The effect of the main structure of the impact-absorbing component)

[0098] By having the aforementioned structure, the impact-absorbing member 30 allows for setting the deformation start time and deformation mode of the first closed section 61 and the second closed section 62 during a side impact. Therefore, the impact-absorbing action of the impact-absorbing member 30 during a side impact can be set according to the characteristics of the vehicle (the presence or absence of the battery housing 100, the layout of the battery housing 100, etc.). This results in higher side impact resistance for the vehicle. Furthermore, since the impact-absorbing member 30 is formed of multiple members (in this embodiment, the first cap member 31 and the second cap member 32), the freedom of shape setting can be further increased compared to the case where the impact-absorbing member 30 is formed of a single member.

[0099] (Detailed structural example of impact-absorbing components)

[0100] In the impact-absorbing member 30, by providing multiple closed-section portions (two closed-section portions 61 and 62 in this embodiment) in the width direction X, the multiple closed-section portions 61 and 62 are collapsed in stages during a side impact, thereby absorbing more impact energy. Furthermore, the impact-absorbing member 30 is formed by combining multiple members (two cap members 31 and 32 in this embodiment). Thus, by combining the strength (tensile strength) and plate thickness of each member 31 and 32, the collapse characteristics of each closed-section portion 61 and 62 can be made to a desired state. For example, one cap member 31 may collapse relatively large during a side impact to absorb the impact, while the other cap member 32 may collapse relatively small during a side impact to suppress the amount of ingress of the side beam 15 and the like in the width direction during a side impact.

[0101] In this embodiment, the impact absorbing member 30 is formed with the same shape in the longitudinal direction Y throughout its entire region, but it is also possible that the shape differs in different portions in the longitudinal direction Y. In this embodiment, the impact absorbing member 30 is formed with a shape that protrudes outward in the width direction X, but it is also possible that it is formed with a shape that protrudes inward in the width direction X (with the same shape in the longitudinal direction X). Figure 2 (The shape shown is symmetrical). The impact absorbing member 30 can be disposed in the entire area of ​​the part where the side beam 15 is disposed, or it can be disposed in a localized area in the front-rear direction Y. In this embodiment, the impact absorbing member 30 is disposed continuously from the front end 15a to the rear end 15b of the side beam 15.

[0102] Preferably, the impact-absorbing member 30 is disposed at least in a position opposite to the floor beams 16 and 17 in the width direction X. According to this structure, the impact from the impact-absorbing member 30 can be efficiently transmitted to the floor beams 16 and 17 during a side impact. This prevents the impact-absorbing member 30 from pressing against the battery casing 100 via the inner member 22 of the side beam. This further improves the performance of protecting the battery casing 100. In this embodiment, the impact-absorbing member 30 is formed in a vertically symmetrical shape, but it can also be a vertically asymmetrical shape. The impact-absorbing member 30 is formed from multiple members, thus facilitating the manufacture of the impact-absorbing member 30 regardless of whether it is vertically symmetrical or asymmetrical.

[0103] In this embodiment, the impact-absorbing member 30 is supported on the side beam 15 within the closed-section space 23 of the side beam 15. Specifically, the impact-absorbing member 30 is disposed between the side wall 213 of the outer member 21 of the side beam and the side wall 223 of the inner member 22 of the side beam. In this embodiment, the impact-absorbing member 30 has a slender shape that decreases in length in the height direction Z as it moves outward toward the width direction X. The impact-absorbing member 30 is elongated in the width direction X, and its length in the width direction X is greater than its length in the height direction Z.

[0104] The first top plate portion 41 suppresses out-of-plane deformation of the pair of longitudinal wall portions 45 and 46 connected to it. In addition, the first top plate portion 41 is the first part of the impact-absorbing member 30 to bear the impact load during a side collision.

[0105] In this embodiment, the first top plate portion 41 is adjacent to the side wall 213 of the side beam outer member 21, but preferably separate from the side beam outer member 21.

[0106] With this preferred structure, it is easy to install the impact-absorbing member 30 within the side beam 15. This is because it eliminates the need to join the first top plate portion 41 to the side wall 213 of the outer member 21 of the side beam. If the first top plate portion 41 were joined to the side wall 213 of the outer member 21 of the side beam by welding, a welding machine would need to be clamped at both the first top plate portion 41 and the side wall 213. Therefore, installing the impact-absorbing member 30 within the side beam 15 is time-consuming. This time-consuming process applies regardless of whether the welding is spot welding, laser welding, or adhesive-based bonding.

[0107] Furthermore, with this preferred structure, in a side collision, the impact-absorbing member 30 can undergo a two-stage collapse by sequentially compressing its two closed sections 61 and 62 while minimizing the impact of the outer member 21 of the side beam, thus improving the impact energy absorption efficiency. In other words, in a side collision, the impact-absorbing member 30 can deform and absorb the impact while being less affected by the deformation of the outer member 21 of the side beam. Therefore, the impact absorption performance of the impact-absorbing member 30 can be utilized more effectively.

[0108] Furthermore, with this preferred structure, in the event of a minor side impact, deformation of the components caused by the impact transmission from the outer side beam member 21 to the impact-absorbing member 30 and the inner side beam member 22 can be suppressed. In a minor side impact, the impact acts on the outer side beam member 21, but the amount of impact transmitted from the outer side beam member 21 to the impact-absorbing member 30 is minimal. Therefore, the impact transmission to the inner side beam member 22 via the impact-absorbing member 30 is less. In this case, the deformation of the side beam 15 is less, thus suppressing the reduction in vehicle performance (straight-line performance, etc.). Additionally, when repairing the vehicle, the sidewall 213 of the outer side beam member 21 needs repair, but the impact-absorbing member 30 and the inner side beam member 22 do not need repair, further reducing the time and cost of vehicle maintenance. On the other hand, when a vehicle is involved in a large side collision, the impact energy can be efficiently absorbed by the deformation of the impact absorption member 30 and the inner member 22 of the side beam by transferring the impact from the outer member 21 of the side beam to the inner member 22 of the side beam through the impact absorption member 30.

[0109] Furthermore, with such a preferred structure, vibration noise caused by the contact between the first top plate portion 41 and the outer member 21 of the side beam can be suppressed, and the impact load from the outer member 21 of the side beam, along with the collapse of the outer member 21, can be transferred to the impact-absorbing member 30 during a side collision. In terms of utilizing the entire first top plate portion 41 to bear the impact load from the side wall 213 of the outer member 21 of the side beam, it is preferable that the first top plate portion 41 is arranged parallel to the side wall 213.

[0110] In this embodiment, the first top plate portion 41 is the shortest part in the height direction Z of the impact absorbing member 30. The boundary between the first top plate portion 41 and each longitudinal wall portion 45, 46 is formed in a curved shape.

[0111] A pair of longitudinal wall portions 45 and 46 are arranged along the width direction X, and the spacing between the pair of longitudinal wall portions 45 and 46 increases as they extend toward the inner member 22 of the side beam. This arrangement of the pair of longitudinal wall portions 45 and 46 allows the upper and lower parts of the impact absorbing member 30 to evenly bear the impact load acting inward from the outer member 21 of the side beam in the width direction X. Therefore, in the event of a side collision, the impact energy absorption of the impact absorbing member 30 can be further improved. Alternatively, the pair of longitudinal wall portions 45 and 46 can also be arranged parallel (horizontally) to the width direction X.

[0112] A first top plate portion 41 is connected to the top end of each pair of longitudinal wall portions 45 and 46 in the width direction X. On the other hand, flanges 47 and 48 are connected to the base ends of the pair of longitudinal wall portions 45 and 46.

[0113] Flanges 47 and 48 are provided on the cap-shaped portion 40 and extend from a pair of longitudinal wall portions 45 and 46. Flanges 47 and 48 are the portions that engage with the side beam 15. In this embodiment, they are engaged with the inner surface of the side beam inner member 22 by the engagement method described above. Flanges 47 and 48 may also not be directly engaged with the side beam inner member 22, or they may be engaged with the side beam inner member 22 via other members.

[0114] Thus, the pair of flanges 47, 48 of the cap-shaped portion 40 engage with the inner member 22 of the side beam. According to this structure, in the event of a side impact, the impact load acting on the first top plate portion 41 can be transferred from the inner member 22 of the side beam to the floor beams 16, 17 with high transmission efficiency. Therefore, through the cooperation of the side beam 15, the impact-absorbing member 30, and the floor beams 16, 17, more impact energy can be absorbed. As a result, the impact of the side beam 15 onto the battery casing 100 during a side impact can be suppressed.

[0115] Flange 47 extends upward from the upper longitudinal wall portion 45, and flange 48 extends downward from the lower longitudinal wall portion 46. In the cap-shaped portion 40, these flanges 47 and 48 are separated from each other, and the cap-shaped portion 40 has a shape that is open to the inner side of the side beam inner member 22 in the width direction X. Thus, it is preferable that the impact absorbing member 30 is joined to the side beam 15 only at the flanges 47 and 48, and no other part of the impact absorbing member 30 is arranged between the flanges 47 and 48 in the height direction Z. With such a structure, the impact absorbing member 30 can be made lighter. In addition, when spot welding the side beam inner member 22 and the impact absorbing member 30, the flanges 47 and 48 and the side beam inner member 22, which are located on the outer side of the pair of longitudinal walls 45 and 46 in the height direction Z, can be welded using a welding machine. Thus, in this embodiment, there are outwardly facing flanges 47 and 48 located on the outer side of the pair of longitudinal walls 45 and 46 in the height direction Z.

[0116] Furthermore, instead of flanges 47 and 48, an inward flange is considered to be provided between the base ends of a pair of longitudinal wall portions 45 and 46, positioned inside the vertical direction Z of the pair of longitudinal wall portions 45 and 46. This inward flange has a portion extending downward from the base end of the longitudinal wall portion 45 and a portion extending upward from the base end of the longitudinal wall portion 46, these portions being integrally formed, thus providing a plate-like portion (one inward flange) between the base ends of the longitudinal wall portions 45 and 46. If this plate-like portion is joined to the inner member 22 of the side beam, it is difficult to clamp the plate-like portion and the inner member 22 of the side beam using a welding machine. Therefore, additional materials such as adhesives are required to join the plate-like member to the inner member 22 of the side beam, reducing the freedom in setting the joining method between the impact-absorbing member and the inner member 22 of the side beam.

[0117] Furthermore, preferably, as in this embodiment, the flanges 47 and 48 of the impact-absorbing member 30 are not disposed between the flanges 211 and 221 and between the flanges 215 and 225 of the side beam 15, but are instead joined to the side wall 223 of the inner member 22 of the side beam. With this preferred structure, it is unnecessary to clamp the flanges 47 and 48 of the impact-absorbing member 30 at the flanges 211, 221 and 215, 225 of the side beam 15, and the joining of the impact-absorbing member 30 does not require the difficult alignment work of welding three or more plate-shaped members. Additionally, there are cases where flanges 211, 221 and 215, 225 are not provided near the front end 15a, near the middle column 13, and near the rear end 15b of the side beam 15. In such cases, it is still possible to join the flanges 47 and 48 of the impact-absorbing member 30 to the side beam 15 near the front end 15a, near the middle column 13, and near the rear end 15b of the side beam 15.

[0118] The second top plate portion 42 suppresses out-of-plane deformation such as the pair of longitudinal wall portions 45, 46 connected to it tilting inwards. The second top plate portion 42 is disposed between the inner surfaces of the pair of longitudinal wall portions 45, 46. The second top plate portion 42 is disposed parallel to the first top plate portion 41.

[0119] The second top plate portion 42 is disposed in the middle portion of the pair of longitudinal wall portions 45 and 46 in the erection direction (width direction X). With this structure, the pair of longitudinal wall portions 45 and 46 can be divided using the second top plate portion 42. That is, in the width direction X, the portions of each longitudinal wall portion 45 and 46 that are further outward from the second top plate portion 42 and those that are further inward from the second top plate portion 42 can be shortened respectively. As a result, out-of-plane deformation of the pair of longitudinal wall portions 45 and 46 during a side impact can be suppressed, and the energy absorption based on wall buckling can be further increased.

[0120] In this embodiment, the second top plate portion 42 is positioned biased towards the outer member 21 of the side beam and the inner member 22 of the side beam. Consequently, in the width direction X, the length from the first top plate portion 41 to the second top plate portion 42 is shorter than the length from the second top plate portion 42 to the side wall 223 of the inner member 22 of the side beam. Specifically, in this embodiment, the second top plate portion 42 is located on the outer side of the boundary between the outer member 21 and the inner member 22 of the side beam in the width direction X, namely the flanges 211, 221 and 215, 225.

[0121] Thus, the second top plate portion 42 is positioned biased towards the outer member 21 of the side beam and the inner member 22 of the side beam. This reduces the space between the first top plate portion 41 and the second top plate portion 42 (the space within the first cap member 31). As a result, in a side impact, out-of-plane deformation of the portion between the first top plate portion 41 and the second top plate portion 42 (the first portions 45a and 46a of the pair of longitudinal wall portions 45 and 46) can be suppressed. Furthermore, in a side impact, by first compressing the first closed section portion 61 and then the second closed section portion 62, impact loads from the width direction X can be absorbed sequentially from the member positioned on the outer side of the width direction X. By performing such a smooth impact absorption action, the impact absorption efficiency of the impact absorption member 30 in absorbing impact energy can be improved.

[0122] According to the above structure, the first closed section portion 61 is formed by the first top plate portion 41, the top-side portions of the pair of longitudinal wall portions 45 and 46 (i.e., the first portions 45a and 46a), and the second top plate portion 42. Furthermore, the second closed section portion 62 is formed by the second top plate portion 42, the base-side portions of the pair of longitudinal wall portions 45 and 46 (i.e., the second portions 45b and 46b), the pair of flanges 47 and 48, and the sidewall 223 of the side beam inner member 22.

[0123] In this embodiment, the impact-absorbing member 30 is formed by combining the first cap member 31 and the second cap member 32.

[0124] Both the first cap member 31 and the second cap member 32 are formed in the shape of a cap. The first cap member 31 includes a first top plate portion 41, first portions 45a and 46a of a pair of longitudinal wall portions 45 and 46, and flanges 49 and 50 formed on these first portions 45a and 46a. The second cap member 32 includes a second top plate portion 42, second portions 45b and 46b of a pair of longitudinal wall portions 45 and 46, and flanges 47 and 48.

[0125] The top plate portion of the first cap member 31 forms a first top plate portion 41, and the top plate portion of the second cap member 32 forms a second top plate portion 42. Furthermore, a pair of longitudinal wall portions of the first cap member 31, namely a pair of first portions 45a and 46a, and a pair of longitudinal wall portions of the second cap member, namely a pair of second portions 45b and 46b, cooperate to form a pair of longitudinal wall portions 45 and 46 of the impact-absorbing member 30. That is, the longitudinal wall portion 45 is formed by the first portion 45a and the second portion 45b, and the longitudinal wall portion 46 is formed by the first portion 46a and the second portion 46b.

[0126] Thus, the impact-absorbing member 30 is formed by two cap members 31 and 32. According to this structure, the impact-absorbing member 30 can be formed by combining two relatively simple structures such as cap members 31 and 32. Furthermore, the degree of freedom in setting the shape of each cap member 31 and 32 can be increased, thereby increasing the degree of freedom in setting the shape of the impact-absorbing member 30. Moreover, the deformation mode of the first cap member 31 during a side impact can be made different from the deformation mode of the second cap member 32, further increasing the degree of freedom in setting the impact-absorbing action based on the impact-absorbing member 30.

[0127] In this embodiment, the first portions 45a and 46a of the first cap member 31 and the corresponding second portions 45b and 46b of the second cap member 32 are arranged in a straight line. "Arranged in a straight line" means that while the first portions 45a and 46a overlap with the corresponding second portions 45b and 46b, creating a step corresponding to the thickness of the first portions 45a and 46a, they are essentially arranged in a straight line.

[0128] With this linear layout, in the event of a side collision, the impact load acting on the impact-absorbing member 30 from the first top plate portion 41 can be transferred with high efficiency from the inner member 22 of the side beam to the floor beams 16 and 17. Thus, through the cooperation of the side beams 15, the impact-absorbing member 30, and the floor beams 16 and 17, more impact energy can be absorbed. As a result, the impact of the side beams 15 onto the battery casing 100 can be suppressed.

[0129] In this embodiment, the base ends of the first portions 45a and 46a in the width direction X are flanges 49 and 50, which are joined to the top ends of the second portions 45b and 46b. In this embodiment, the first portions 45a and 46a, including flanges 49 and 50, are respectively formed in a straight line shape, and the inner surfaces of flanges 49 and 50 are joined to the outer surfaces of the second portions 45b and 46b. The flanges 49 and 50 of the first portions 45a and 46a are joined to the second portions 45b and 46b in such a way that the first cap member 31 does not detach from the second cap member 32 even when an impact load is applied to the impact absorbing member 30 by design.

[0130] In this way, the inner surfaces of the pair of first portions 45a and 46a of the first cap member 31 are joined to the outer surfaces of the pair of second portions 45b and 46b of the second cap member 32. Thus, a structure in which each of the first portions 45a and 46a and the corresponding second portions 45b and 46b are arranged in a straight line can be realized.

[0131] The length H1 of the first closed section portion 61 in the width direction X is smaller than the length H2 of the second closed section portion 62 in the width direction X (H2 > H1). The ratio of these lengths, H1 / H2, is preferably 1 / 3 to 1 / 2. If it is within the range of the above-mentioned ratio H1 / H2, then in the event of a side collision, the impact absorption effect generated by the collapse of the first cap member 31 and the impact absorption effect generated by the collapse of the second cap member 32 will not deviate to extremes, and the overall impact absorption efficiency of the impact absorption member 30 can be improved.

[0132] Furthermore, the relationship between the length H1 of the first closed section portion 61 in the width direction X and the plate thickness t1 of the first cap member 31 is described. The smaller H1 / t1 is, the better the out-of-plane deformation of the first cap member 31 can be suppressed during a side impact. Similarly, the relationship between the length H2 of the second closed section portion 62 in the width direction X and the plate thickness t2 of the second cap member 32 is described. The smaller H2 / t2 is, the better the out-of-plane deformation of the second cap member 32 can be suppressed during a side impact.

[0133] Next, the material of the impact absorbing component 30 will be explained.

[0134] Preferably, the impact-absorbing member 30 is formed of steel sheet. If the impact-absorbing member is, for example, made of aluminum, and aluminum is placed inside a steel side beam, electrolytic corrosion (dissimilar metal contact corrosion) occurs due to the contact between aluminum and iron, which are dissimilar metals. Therefore, electrolytic corrosion countermeasures (rust prevention treatment) are required. On the other hand, if the impact-absorbing member 30 is made of steel, the aforementioned electrolytic corrosion countermeasures are not required, and iron, which is cheaper than aluminum, can be used, thus reducing the manufacturing cost of the vehicle body 1.

[0135] In this embodiment, the first cap member 31 and the second cap member 32 of the impact absorbing member 30 are each formed of steel plate. The tensile strength of each cap member 31 and 32 can be 780 MPa to 2.5 GPa, and can also be 590 MPa to 2.5 GPa. The lower limit of the tensile strength of each cap member 31 and 32 can also be 980 MPa, 1.3 GPa, 1.5 GPa, 1.7 GPa, 2.0 GPa, or 2.3 GPa. Similarly, the upper limit of the tensile strength of each cap member 31 and 32 can also be 1.5 GPa, 1.7 GPa, 2.0 GPa, or 2.3 GPa.

[0136] Tensile strength can be evaluated according to JIS Z 2241:2011. As a test piece for determining tensile strength, test piece No. 5 of JIS Z 2241:2011 can be shown as an example. As for the sampling location of the tensile test piece, for example, the central portion of a pair of longitudinal wall portions 45, 46 of each cap member 31, 32 can be shown as an example.

[0137] As a Vickers hardness equivalent to the tensile strength of the aforementioned cap components 31 and 32, examples of Vickers hardness for each cap component 31 and 32 can be given. Examples of Vickers hardness HV1 and HV2 for each cap component 31 and 32 can be 240 to 780. The lower limit of Vickers hardness HV1 and HV2 for each cap component 31 and 32 can also be 180 corresponding to 590 MPa, 240 corresponding to 780 MPa, 300 corresponding to 980 MPa, 400 corresponding to 1.3 GPa, 460 corresponding to 1.5 GPa, 520 corresponding to 1.7 GPa, 620 corresponding to 2.0 GPa, or 710 corresponding to 2.3 GPa. In addition, the upper limit of the Vickers hardness HV1 and HV2 of each cap component 31 and 32 can also be 460 corresponding to 1.5GPa, 520 corresponding to 1.7GPa, 620 corresponding to 2.0GPa, 710 corresponding to 2.3GPa, or 780 corresponding to 2.5GPa.

[0138] The Vickers hardness of each cap component 31 and 32 can be measured as follows. Vickers hardness (HV1) "HV1" refers to the "hardness symbol" (JIS Z 2244-1:2020) when the Vickers hardness test is performed with a test force of 1 kgf (9.807 N). The Vickers hardness is measured as follows. First, a test specimen is cut from a flat plate portion such as the first top plate portion 41 of the first cap component 31 with the cut surface (test surface) parallel to the thickness direction of the flat plate portion. The specimen is then embedded in resin and the cut surface is ground. Then, at a depth of 1 / 4 of the plate thickness at the cut surface (test surface) from the surface of the test specimen, 10 points are measured at 0.5 mm intervals under a test force of 1 kgf (9.807 N), and the average value is taken.

[0139] The Vickers hardness (HV2) "HV2" is the value obtained by cutting a test specimen from a flat portion such as the second top plate portion 42 of the second cap member 32 instead of the first top plate portion 41, and performing the above-mentioned test.

[0140] In this embodiment, the tensile strength TS1 (Vickers hardness HV1) of the first cap member 31 is set to be lower than the tensile strength TS2 (Vickers hardness HV2) of the second cap member 32. That is, the strength of the outer member 21 side of the impact absorbing member 30 is lower than the strength of the inner member 22 side. With this structure, the strength of the first top plate portion 41 is set to be lower than the strength of the second top plate portion 42.

[0141] By setting such tensile strength (Vickers hardness), in a side impact, the first cap member 31 can begin to deform and absorb impact energy before the second cap member 32. Within the closed cross-sectional space 23, the first cap member 31, located on the side away from the battery casing 100 in the impact-absorbing member 30, deforms first, thereby delaying the deformation of the second cap member 32 on the side closer to the battery casing 100. In other words, the deformation of the second cap member 32 can be suppressed until the first cap member 31 is fully deformed. As a result, the amount of impact energy absorbed by the collapse of the first cap member 31 can be increased, and the contact between the inner member 22 of the side beam, which collapses together with the collapse of the second cap member 32, and the side wall 100b of the battery casing 100 can be suppressed. Moreover, the second cap member 32 is of high strength, thus further increasing the amount of impact energy absorbed by the second cap member 32.

[0142] The tensile strength TS2 (Vickers hardness HV2) of the second cap member 32 is preferably about 1.3 to 1.7 times the tensile strength TS1 (Vickers hardness HV1) of the first cap member 31, and can be exemplified as about 1.5 times. With this setting, the first cap member 31 can be crushed during a side impact, and the second cap member 32 can begin to crush after the first cap member 31 has fully collapsed. Furthermore, it can suppress the situation where cracks form in the first cap member 31 during a large-scale crushing event during a side impact, thus reducing the impact energy absorption efficiency. As a more specific example, a structure can be illustrated by setting the tensile strength TS1 of the first cap member 31 to 980 MPa and the tensile strength TS2 of the second cap member 32 to 1.5 GPa. In this structure, compared to setting the tensile strengths TS1 and TS2 of each cap member 31 and 32 to be the same, the impact energy absorption value can be further improved.

[0143] The plate thicknesses t1 and t2 of each cap component 31 and 32 can be 0.8 mm to 2.3 mm, and can also be 1.4 mm to 2.3 mm. The plate thicknesses t1 and t2 of each cap component 31 and 32 can be the same or different, but from a lightweighting point of view, smaller plate thicknesses t1 and t2 are preferred. The lower limits of the plate thicknesses t1 and t2 of each cap component 31 and 32 can be 0.8 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, and 2.2 mm. The upper limits of the plate thicknesses t1 and t2 of each cap component 31 and 32 can be 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, and 2.2 mm.

[0144] In this embodiment, the plate thickness t1 of the first cap member 31 is set to be smaller than the plate thickness t2 of the second cap member 32.

[0145] The thickness t2 of the second cap member 32 is preferably about 1.3 to 1.7 times the thickness t1 of the first cap member 31, and can be exemplified as about 1.5 times. By setting these thickness ratios t2 / t1 to the above range, the second cap member 32 can begin to collapse after the first cap member 31 has fully collapsed during a side impact.

[0146] The tensile strength ratio TS2 / TS1 of each cap component 31 and 32 can be set to 1.3 to 1.7 (e.g., 1.5) and the plate thickness ratio t2 / t1 can be set to 1, or the tensile strength ratio TS2 / TS1 of each cap component 31 and 32 can be set to 1 and the plate thickness ratio t2 / t1 can be set to 1.3 to 1.7 (e.g., 1.5).

[0147] The combination of the plate thicknesses t1 and t2 of each cap component 31 and 32 with the tensile strengths TS1 and TS2 can be set such that the first cap component 31 begins to collapse before the second cap component 32 in a side collision, and the second cap component 32 begins to collapse after the first cap component 31 has fully collapsed.

[0148] For the Vickers hardness HV1 and plate thickness t1 at the first cap member 31, and the Vickers hardness HV2 and plate thickness t2 at the second cap member 32, it is preferred that 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, and HV1×t1<HV2×t2.

[0149] By setting HV1 to 180 ≤ HV1, the strength of the first cap member 31 can be sufficiently ensured, and the impact energy absorption efficiency can be improved. Furthermore, by setting HV2 ≤ 780, cracking during deformation of the second cap member 32 can be suppressed, further improving impact energy absorption efficiency. Additionally, by setting 0.8 mm ≤ t1, the stiffness of the first cap member 31 can be sufficiently ensured, suppressing cracking in the first cap member 31. Furthermore, by setting t2 ≤ 2.3 mm, the second cap member 32 can be made lighter. Moreover, by setting HV1 × t1 < HV2 × t2, the following operation can be performed more reliably: in a side impact, the first cap member 31 begins to collapse before the second cap member 32, and the second cap member 32 begins to collapse after the first cap member 31 has fully collapsed.

[0150] Thus, the impact absorbing component 30 is formed by multiple components 31 and 32, so there is a high degree of freedom in distinguishing and using the Vickers hardness HV1 and HV2 of each component 31 and 32, and in selecting the plate thickness t1 and t2.

[0151] With the above structure, in this embodiment, the degree of freedom in setting the shape of the impact-absorbing member 30 can be further improved, and the side beam structure 14 and the lower structure 2 of the vehicle can achieve high side impact resistance performance.

[0152] In particular, in this embodiment, impact-absorbing members 30 are arranged on both sides (left and right sides) of the width direction X of the vehicle body 1, so that the impact-absorbing members 30 can absorb the impact energy regardless of whether a side collision occurs on the right or left side of the vehicle body 1.

[0153] Furthermore, the impact-absorbing member 30 disposed on the side of the battery housing 100 can absorb impact energy. As a result, even in the event of a side collision, the gap A between the inner member 22 of the side beam and the side wall 100b of the battery housing 100 can be suppressed from disappearing. Therefore, the contact between the side beam 15 and the side wall 100b of the battery housing 100 can be suppressed.

[0154] The embodiments of this disclosure have been described above. However, this disclosure is not limited to the embodiments described above. Various modifications can be made to this disclosure within the scope of the claims. Furthermore, the following mainly describes structures different from the embodiments and variations described above, and the same reference numerals are used to refer to the same structures, with detailed descriptions omitted.

[0155] [First variation of the first embodiment]

[0156] Figure 3 This is a schematic cross-sectional view showing the main parts of a first variation of the first embodiment of the present disclosure. In this embodiment, the second top plate portion 42 is positioned biased towards the outer member 21 of the side beam and the inner member 22 of the side beam. On the other hand, in the first variation of the first embodiment, the second top plate portion 42 is positioned biased towards the inner member 22 of the side beam and the outer member 21 of the side beam.

[0157] Therefore, in the width direction X, the length from the first top plate portion 41 to the second top plate portion 42 is longer than the length from the second top plate portion 42 to the side beam inner member 22.

[0158] This arrangement of the second top plate portion 42 increases the space (first cap member 31) between the first top plate portion 41 and the second top plate portion 42. As a result, in a side impact, the impact energy that can be absorbed by the collapse of the first portions 45a and 46a of the pair of longitudinal wall portions 45 and 46 can be increased. Moreover, in a side impact, by first collapsing the first closed section portion 61 and then collapsing the second closed section portion 62, the impact load from the width direction X can be absorbed sequentially from the member located on the outer side in the width direction X. By performing such a smooth impact absorption action, the impact absorption member 30 can improve the impact energy absorption efficiency.

[0159] [Second variation of the first embodiment]

[0160] In this embodiment, an example has been described where the tensile strength TS1 (Vickers hardness HV1) of the first cap member 31 is lower than the tensile strength TS2 (Vickers hardness HV2) of the second cap member 32. However, this is not always the case. The tensile strength TS1 (Vickers hardness HV1) of the first cap member 31 can also be higher than the tensile strength TS2 (Vickers hardness HV1) of the second cap member 32. In this case, a structure obtained by swapping the tensile strength TS1 (Vickers hardness HV1) of the first cap member 31 and the tensile strength TS2 (Vickers hardness HV1) of the second cap member 32 can be illustrated. With such a structure, the strength on the outer member 21 side of the impact-absorbing member 30 can be higher than the strength on the inner member 22 side.

[0161] With this structure, the peak value of the impact load acting on the first cap member 31 can be further increased during a side collision, and the first cap member 31 can absorb more impact energy.

[0162] Furthermore, in a second variation of this first embodiment, a structure can be illustrated by interchangeing the plate thickness t1 of the first cap member 31 and the plate thickness t2 of the second cap member 32. That is, the plate thickness t1 of the first cap member 31 can be larger than the plate thickness t2 of the second cap member 32. With such a structure, the peak value of the impact load acting on the first cap member 31 can be further increased during a side impact, and more impact energy can be absorbed by the first cap member 31.

[0163] [Third variation of the first embodiment]

[0164] Figure 4 This is a schematic perspective view showing the main parts of a third modification of the first embodiment of this disclosure. Figure 4 The impact-absorbing member 30 shown has reinforcing ribs 70. The reinforcing ribs 70 can be formed in the first top plate portion 41 of the impact-absorbing member 30, in a pair of longitudinal wall portions 45 and 46, or in the second top plate portion 42. In the first modified example, the reinforcing ribs 70 are formed in the pair of longitudinal wall portions 45 and 46.

[0165] The reinforcing rib 70 includes a first reinforcing rib 71 formed in the first portion 45a, 46a of a pair of longitudinal wall portions 45, 46 and a second reinforcing rib 72 formed in the second portion 45b, 46b of a pair of longitudinal wall portions 45, 46.

[0166] The first reinforcing rib 71 is provided to improve the impact absorption effect during side collisions by increasing the resistance of the impact-absorbing member 30 to bending deformation. The first reinforcing rib 71 extends in the front-rear direction Y and is formed by making the first portions 45a and 46a undulate in the height direction Z. In the third variation of this first embodiment, it is formed by making the first portions 45a and 46a recessed inward toward the closed cross-section space 23. Alternatively, the first reinforcing rib 71 can also be formed by making the first portions 45a and 46a recessed outward toward the closed cross-section space 23. One or more first reinforcing ribs 71 are formed in the width direction X (two in this third variation), all of which have the same shape in the front-rear direction Y.

[0167] The second reinforcing rib 72 is provided to suppress out-of-plane deformation of the longitudinal wall portions 45 and 46 during a side impact. The second reinforcing rib 72 extends in the width direction X and is formed by undulating the second portions 45b and 46b in the height direction Z. In the first modified example, it is formed by recessing the second portions 45b and 46b inwards towards the closed cross-section space 23. Alternatively, the second reinforcing rib 72 can also be formed by recessing the second portions 45b and 46b outwards towards the closed cross-section space 23. Multiple second reinforcing ribs 72 are formed separately in the front-rear direction Y.

[0168] The first reinforcing rib 71 may also be formed in the first top plate portion 41. Alternatively, a second reinforcing rib 72 may be formed in the first portions 45a and 46a of the pair of longitudinal wall portions 45 and 46, and a first reinforcing rib 71 may be formed in the second portions 45b and 46b. Furthermore, the reinforcing rib 70 may be formed throughout the entire area of ​​the impact-absorbing member 30 in the longitudinal direction Y, or it may be formed only in the portions where the floor beams 16 and 17 are located.

[0169] Thus, by forming reinforcing ribs 70 in the impact-absorbing member 30, the buckling of the impact-absorbing member 30 during a side collision can be suppressed, resulting in the absorption of more impact energy.

[0170] Furthermore, for structures like the second reinforcing rib 72, which are formed in multiple separate parts in the front-rear direction Y, it is difficult to manufacture the impact-absorbing member 30 by extrusion molding of aluminum alloy. However, if the impact-absorbing member 30 is made of steel plate, then such a second reinforcing rib 72 can be formed.

[0171] [Fourth variation of the first embodiment]

[0172] Figure 5This is a cross-sectional view showing the main parts of the fourth variation of the first embodiment of this disclosure. In the above embodiment, the structure of the impact-absorbing member 30 formed by two cap members 31 and 32 was described as an example, but it may not be like this. In the fourth variation of this first embodiment, the impact-absorbing member 30 is formed by a cap member 35 and a second top plate member 36 provided within the cap member 35 as a top plate member.

[0173] The cap member 35 is formed in the shape of a cap and includes a first top plate portion 41, a pair of longitudinal wall portions 45 and 46, and flanges 47 and 48. The cap-shaped portion 40 is formed by the cap member 35. In the fourth variation of this first embodiment, the pair of longitudinal wall portions 45 and 46 are arranged in a tapered configuration where the distance between them narrows as they extend outward toward the width direction X.

[0174] The second top plate member 36 is disposed between the inner surfaces of a pair of longitudinal wall portions 45 and 46. In this fourth modification, the second top plate member 36 has a shape that protrudes toward the first top plate portion 41.

[0175] By using the shape of the second top plate member 36, the efficiency of impact energy transmission can be improved during side collisions, and the effect of suppressing out-of-plane deformation of the cap member 35 can be enhanced.

[0176] The second top plate member 36 will be described in more detail. The second top plate member 36 includes a second top plate portion 42 parallel to the first top plate portion 41, and flanges 37 and 38 located at both ends in the height direction Z of the second top plate portion 42 and joined to the inner surfaces of a pair of longitudinal wall portions 45 and 46. The upper flange 37 is curved away from the first top plate portion 41 as it approaches the upper longitudinal wall portion 45. The lower flange 38 is curved away from the first top plate portion 41 as it approaches the lower longitudinal wall portion 46.

[0177] The tensile strength and plate thickness of the cap member 35 can also be set in the same way as the tensile strength TS1 and plate thickness t1 of the first cap member 31 in the embodiment. The tensile strength and plate thickness of the second top plate member 36 can also be set in the same way as the tensile strength TS2 and plate thickness t2 of the second cap member 32 in the embodiment.

[0178] Furthermore, for the Vickers hardness HV2 and plate thickness t2 at the cap member 35, and the Vickers hardness HV1 and plate thickness t1 at the second top plate member 36, it is preferable that 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, and HV1×t1<HV2×t2. The meanings of each value are the same as in the first embodiment. By satisfying such conditions, the following operation can be performed more reliably: in a side impact, the first closed section 61 begins to collapse before the second closed section 62, and the second closed section 62 begins to collapse after the first closed section 61 has fully collapsed.

[0179] [Fifth variation of the first embodiment]

[0180] Figure 6 This is a cross-sectional view showing the main parts of a fifth modification of the first embodiment of the present disclosure. In the embodiment, two closed-section portions 61 and 62 are formed by two cap members 31 and 32. However, in the impact-absorbing member 30, three or more closed-section portions may be formed by three or more n members. In this fifth modification, three closed-section portions 61, 62, and 63 are formed by three cap members 31, 32, and 33.

[0181] The impact-absorbing member 30 may also include the three cap members 31, 32, and 33 described above. The first cap member 31 has a first top plate portion 41 and first portions 45a and 46a that are parts of a pair of longitudinal wall portions 45 and 46. The second cap member 32 has a second top plate portion 42 and second portions 45b and 46b that are parts of a pair of longitudinal wall portions 45 and 46. The third cap member 33 includes a third top plate portion 43, third portions 45c and 46c that are parts of a pair of longitudinal wall portions 45 and 46, and a pair of flanges 47 and 48. The third top plate portion 43 connects the pair of third portions 45c and 46c. The longitudinal wall portion 45 is formed by the first portion 45a, the second portion 45b, and the third portion 45c. Similarly, the longitudinal wall portion 46 is formed by the first portion 46a, the second portion 46b, and the third portion 46c.

[0182] A reinforcing rib 71 extending uniformly in the front-rear direction Y is formed on the first top plate portion 41 of the first cap member 31, but this reinforcing rib 71 may be omitted. The inner surfaces of the base ends of the first portions 45a and 46a of the first cap member 31, i.e., the flanges 49 and 50, are joined to the outer surfaces of the second portions 45b and 46b of the second cap member 32. The inner surfaces of the base ends of the second portions 45b and 46b of the second cap member 32, i.e., the flanges 79 and 80, are joined to the outer surfaces of the third portions 45c and 46c of the third cap member 33.

[0183] The first closed section portion 61 is formed by the first cap member 31 and the second top plate portion 42. Similarly, the second closed section portion 62 is formed by the second cap member 32 and the third top plate portion 43. In addition, the third closed section portion 63 is formed by the third cap member 33 and the side wall 223 of the side beam inner member 22.

[0184] In this fifth variation, the lengths of the closed section portions 61, 62, and 63 in the width direction X are approximately the same, but they may also be different from each other. For example, in the width direction X, the length of the third closed section portion 63 may be greater than the length of the second closed section portion 62 and the length of the first closed section portion 61, or the length of the third closed section portion 63 may be less than the length of the second closed section portion 62 and the length of the first closed section portion 61.

[0185] As described above, when three or more closed sections are formed, the order in which the closed sections 61, 62, and 63 begin to collapse and the ease of collapse during a side impact can be determined by setting the strength and plate thickness of each closed section 61, 62, and 63.

[0186] [Other variations of the first embodiment]

[0187] In the first embodiment and various modifications described above, a reinforcing member may also be sandwiched between the impact-absorbing member 30 and the floor beams 16 and 17. With this reinforcing member present, it is possible to suppress the bending of the floor beams 16 and 17 due to the impact load transmitted from the impact-absorbing member 30 to the floor beams 16 and 17 via the side beam 15.

[0188] Furthermore, the impact-absorbing member 30 in the first embodiment and various modifications described above can be formed from aluminum alloy or from composite materials such as CFRP (Carbon Fiber Reinforced Plastics).

[0189] Furthermore, in the first embodiment and various modifications described above, an example was given of a structure that transmits the impact load during a side collision to the floor beams 16 and 17 instead of to the battery casing 100. However, this is not always the case; a structure that transmits the impact load during a side collision to the battery casing 100 and absorbs the impact is also possible.

[0190] Furthermore, in the first embodiment and various modifications described above, the example given is a configuration where the first top plate portion 41 is separated from the side beam outer member 21. However, this configuration may not be the case; for example, it may be as follows: Figure 7 As shown, the first top plate portion 41 contacts the side wall 213 without engaging with it. In this structure, during a side impact, the impact-absorbing member 30 can undergo a two-stage collapse by sequentially compressing through the two closed section portions 61 and 62 while minimizing the impact of deformation of the side beam outer member 21. This improves the efficiency of impact energy absorption. In other words, during a side impact, the impact-absorbing member 30 can deform and absorb the impact while being less affected by the deformation of the side beam outer member 21. Therefore, the impact absorption performance of the impact-absorbing member 30 can be utilized more effectively.

[0191] [Second Embodiment]

[0192] (Body)

[0193] Figure 8This is an exploded perspective view showing a portion of the car body 1, including the lower structure 502, which includes the side beam structure 514 of the second embodiment of this disclosure. Figure 9 It is along the lower structure 502 Figure 8 A cross-sectional view of the IX-IX line. Furthermore... Figure 9 This diagram shows the battery casing 600 fixed to the lower structure 502; the inner side of the cross-section is omitted. In this specification, the direction along the travel direction of the vehicle body 501 (vehicle) is defined as the longitudinal direction Y of the vehicle body; the travel direction of the vehicle body is defined as the front; the opposite side is defined as the rear; the vertical direction of the vehicle body is defined as the height direction Z; and the direction orthogonal to the longitudinal direction Y and the height direction Z is defined as the width direction X of the vehicle body. Furthermore, in the width direction X, the direction away from the center of the vehicle body 501 is defined as the outer side, and the opposite direction is defined as the inner side. In addition, in this specification, unless otherwise specified, the cross-section orthogonal to the longitudinal direction Y is simply referred to as a "cross-section".

[0194] like Figure 8 and Figure 9 As shown, body 501 is a part of a vehicle, and a car can be cited as an example of a vehicle. As an example of a car, a passenger car can be cited. Examples of such passenger cars include sedan passenger cars, coupe passenger cars, hatchback passenger cars, minivan passenger cars, and SUV (Sport Utility Vehicle) passenger cars. Furthermore, the vehicle can be, for example, an electric vehicle (Battery Electric Vehicle) or a hybrid vehicle (HV) including a plug-in hybrid, capable of driving the drive wheels using electricity from a battery 601 located at the lower part of body 501.

[0195] The vehicle body 501 includes a frame 510 and a battery casing 600.

[0196] The frame 510 has a front column 511, a top column 512, a middle column 513, a side beam structure 514 including side beams 515, floor beams 516 and 517, and a floor panel 518.

[0197] The front pillar 511, the top pillar 512, the middle pillar 513, and the side beam structure 514 including the side beam 515 are provided separately in the width direction X.

[0198] The front pillar 511 has: a pillar member 511a that extends upward and rearward, and is joined to the top pillar 512; and a pillar member 511b that is disposed below the pillar member 511a.

[0199] The top pillar 512 is located on the roof of the vehicle body 501 and extends rearward from the pillar member 511a.

[0200] The central column 513 is configured along the height direction Z, connecting the top column 512 and the side beam 515.

[0201] Side beam 515 is an example of a "structural member" of this disclosure. Side beam 515 is provided at the lower part of the outer portion in the width direction X of the vehicle body 501. Side beam 515 is connected to the lower part of the center pillar 513 and is arranged along the longitudinal direction Y of the vehicle body 501. Side beam 515 forms a closed section shape in a section orthogonal to the longitudinal direction Y.

[0202] Floor crossbeams 516 and 517 are members extending in the width direction X, positioned between and connecting a pair of left and right side beams 515 and 515. Floor crossbeams 516 and 517 are located on the front seat side of the passenger compartment (cabin) formed by the vehicle body 501. Floor crossbeams 516 and 517 are separately positioned in the front-rear direction Y, with floor crossbeam 17 positioned behind floor crossbeam 16. The cross-sectional shape of each floor crossbeam 516 and 517, orthogonal to the width direction X, is a cap shape, cooperating with the floor panel 518 to form a closed cross-section. The floor panel 518 forms the bottom of the passenger compartment of the vehicle body 501 and is fixed to the floor crossbeams 516 and 517.

[0203] Slide rails (not shown) are installed on floor beams 516 and 517. The slide rails support the seats (not shown) for occupants to sit on.

[0204] A plate-shaped floor panel 518 is provided below the floor beams 516 and 517. A battery housing 600 is provided below the floor panel 518. The battery housing 600 houses a battery 601 containing batteries such as lithium-ion batteries.

[0205] To protect the battery 601 in a side collision with a utility pole or similar object (pole-side collision), the side beam 515 is positioned outward of the battery 601 in the width direction X. Hereinafter, a side collision will be simply referred to as a "side collision." The side beam 515 extends in the longitudinal direction Y. The battery housing 600 may also be fixed to the side beam 515. In this second embodiment, the width direction end 600a of the battery housing 600 is fixed to, for example, the lower wall 724 of the side beam inner member 522 (described later) of the side beam 515. A side wall 600b, for example, rising upward from the width direction end 600a, is formed as a protective wall for the battery 601 in the middle portion of the battery housing 600 in the width direction X. The battery 601 is positioned inward of the side wall 600b in the width direction X. A gap 500A is formed between the side wall 600b and the side beam inner member 522. The gap 500A varies depending on the vehicle type, but can be exemplified as a value ranging from a few millimeters to several hundred millimeters. Furthermore, the structure of the battery housing 600 described in this embodiment is just one example. As long as the battery housing 600 is positioned inside the side beam 515 in the width direction X, there are no limitations on its specific shape or configuration.

[0206] (Side beam construction)

[0207] Hereinafter, when describing the side beam structure 514, unless otherwise specified, the structure at the section orthogonal to the longitudinal direction Y will be described. A pair of side beam structures 514 are provided separately in the width direction X. The lower structure 502 of the vehicle body 501 includes each side beam structure 514 and the battery housing 600.

[0208] Each side beam structure 514 includes the aforementioned side beam 515 and impact-absorbing member 530.

[0209] The side beam 515 includes an outer side beam member 521 and an inner side beam member 522 disposed inside the outer side beam member 521 in the width direction X.

[0210] The outer member 521 and the inner member 522 of the side beam each have a cap-shaped cross section, which together form a closed cross section space 523 at the side beam 515.

[0211] The outer side beam member 521 has a shape that opens inward in the width direction X, and the inner side beam member 522 has a shape that opens outward in the width direction X. The outer side beam member 521 and the inner side beam member 522 are fixed together by welding or fastening members when their flanges 711, 721 and 715, 725 are abutted against each other. In this embodiment, the outer side beam member 521 and the inner side beam member 522 are joined together, for example, by welding. Various welding methods can be used, such as spot welding, TIG welding, arc welding, laser welding, and plasma welding. Fastening members can be structural adhesives, rivets, straps, or nuts; various components can be used. The joining method for joining other parts of the vehicle body 501 is the same as described above.

[0212] The outer member 521 of the side beam has an upper flange 711, an upper wall 712 extending outward from the upper flange 711 in the width direction X, a side wall 713 extending downward from the upper wall 712, a lower wall 714 extending inward from the side wall 713 in the width direction X, and a lower flange 715 extending downward from the lower wall 714.

[0213] The inner member 522 of the side beam has an upper flange 721, an upper wall 722 extending inward from the upper flange 721 in the width direction X, a side wall 723 extending downward from the upper wall 722 and engaging with the floor beams 516 and 517, a lower wall 724 extending outward from the side wall 723 in the width direction X, and a lower flange 725 extending downward from the lower wall 724.

[0214] The upper flanges 711 and 721 are joined together by the joining method described above. Similarly, the lower flanges 715 and 725 are joined together by the joining method described above.

[0215] The upper wall 712 and lower wall 714 of the outer member 521 of the side beam can be parallel to each other along the width direction X, or inclined in a manner that varies in spacing in the height direction Z as it extends outward toward the width direction X. Similarly, the upper wall 722 and lower wall 724 of the inner member 522 of the side beam can be parallel to each other along the width direction X, or inclined in a manner that varies in spacing in the height direction Z as it extends inward toward the width direction X.

[0216] Furthermore, the side beam 515 can be either symmetrical or asymmetrical in the width direction X, and there is no specific limitation on its shape.

[0217] (Main structure of impact absorbing components)

[0218] The impact absorbing member 530 works in conjunction with the side beam 515 to plastically deform during a side collision, thereby absorbing the impact energy of the side collision.

[0219] The impact-absorbing member 530 is formed of multiple members (in this embodiment, a first cap member 31 and a second cap member 32), and is supported on the side beam 515 within the closed cross-sectional space 523 of the side beam 515. Specifically, the impact-absorbing member 530 has a second cap member 532 and a first cap member 531, respectively formed in a cap shape and arranged in the width direction X, in a cross-section orthogonal to the longitudinal direction Y. Furthermore, the impact-absorbing member 530 is formed by combining the second cap member 532 and the first cap member 531.

[0220] The impact-absorbing member 530 includes: a cap-shaped portion 540 having a first top plate portion 531e extending in the height direction Z and a pair of longitudinal wall portions 545, 546 extending from both ends of the first top plate portion 531e in the height direction Z along the width direction X; and a second top plate portion 532e, which is separately disposed from the first top plate portion 531e in the width direction X, connecting the pair of longitudinal wall portions 545, 546 to each other.

[0221] The second top plate portion 532e divides the inner space of the hat-shaped portion 540 in the width direction X, thereby forming a first closed section portion 561 including the first top plate portion 531e and a second closed section portion 562 adjacent to the first closed section portion 561 in the width direction X. The impact absorbing member 530 is separated from the side beam outer member 521, or the impact absorbing member 530 is in contact with the side beam outer member 521 without being engaged with it.

[0222] The first cap member 531 has: a pair of first flanges 531a, 531b that engage with the second top plate portion 532e; a pair of first longitudinal wall portions 531c, 531d that extend from the pair of first flanges 531a, 531b; and a first top plate portion 531e that connects the pair of first longitudinal wall portions 531c, 531d.

[0223] The second cap member 532 has: a pair of second flanges 532a and 532b supported on the side beam 515; a pair of second longitudinal wall portions 532c and 532d extending from the pair of second flanges 532a and 532b; and a second top plate portion 532e connecting the pair of second longitudinal wall portions 532c and 532d.

[0224] (The effect of the main structure of the impact-absorbing component)

[0225] By having the aforementioned structure, the impact-absorbing member 530 forms multiple ridge portions 532f, 532g, 532h, 532i, 531f, 531g, 531h, and 531i. Therefore, during a side impact, the impact energy absorption efficiency during the deformation of the closed cross-section of the second cap member 532 and the first cap member 531 is improved through the action of these multiple ridge portions 532f, 532g, 532h, 532i, 531f, 531g, 531h, and 531i. In particular, the multiple ridge portions 531f, 531g, 531h, and 531i are formed in the first cap member 531, which is the first to bear the impact load, further increasing the amount of impact energy absorbed when the first cap member 531 collapses. As a result, the impact energy absorption efficiency of the impact-absorbing member 530 is improved. Therefore, the impact-absorbing member 530 can be made lightweight, and the amount of impact energy absorbed by the impact-absorbing member 530 can be increased, further improving the weight efficiency of impact energy absorption. Moreover, by adjusting the shape of the second cap member 532 and the shape of the first cap member 531, the deformation start time and deformation mode of the second cap member 532 and the first cap member 531 during a side collision can be set. Therefore, the impact absorption action of the impact-absorbing member 530 during a side collision can be set according to the characteristics of the vehicle (the presence or absence of the battery housing 600, the layout of the battery housing 600, etc.). As a result, higher side collision resistance performance can be achieved for the vehicle. Furthermore, since the impact-absorbing member 530 is formed by multiple members (the second cap member 532 and the first cap member 531 in this embodiment), the freedom of shape setting can be further increased compared to the case where the impact-absorbing member 530 is formed by a single member.

[0226] (Detailed structural example of impact-absorbing components)

[0227] In the impact-absorbing member 530, by forming multiple closed-section portions (in this embodiment, two closed-section portions 561 and 562 formed by the side beam 515, the second cap member 532, and the first cap member 531) in the width direction X, the multiple closed-section portions 561 and 562 are collapsed in stages during a side impact, thereby absorbing more impact energy. Furthermore, the impact-absorbing member 530 is formed by multiple members (in this embodiment, two cap members 531 and 532). Therefore, by combining the strength (tensile strength) and plate thickness of each cap member 531 and 532, the collapse characteristics of each closed-section portion 561 and 562 can be made to a desired state. For example, the first cap member 531 may collapse relatively large during a side impact (in the initial stage of a side impact) to absorb the impact, while the second cap member 532 may collapse relatively small during a side impact to suppress the amount of intrusion of the side beam 515 and the like into the width direction during a side impact.

[0228] In this embodiment, the impact absorbing member 530 has the same cross-sectional shape throughout its entire region, but it may also have different shapes in different portions along the front-rear direction Y. In this embodiment, the impact absorbing member 530 is formed with a shape that protrudes outward in the width direction X, but it may also be formed with a shape that protrudes inward in the width direction X (in the same direction as...). Figure 9 (The shape shown is symmetrical). The impact absorbing member 530 can be disposed in the entire area of ​​the part where the side beam 515 is disposed, or it can be disposed in a localized area in the front-rear direction Y. In this embodiment, the impact absorbing member 530 is disposed continuously from the front end 515a to the rear end 515b of the side beam 515.

[0229] In this embodiment, the impact absorbing member 530 is formed in a top-to-bottom symmetrical shape, but it can also be a top-to-bottom asymmetrical shape. The impact absorbing member 530 is formed from multiple members, so that the impact absorbing member 530 can be easily manufactured regardless of whether it is a top-to-bottom symmetrical or top-to-bottom asymmetrical shape.

[0230] In the second embodiment, the impact-absorbing member 530 is disposed between the side wall 713 of the outer member 521 and the side wall 723 of the inner member 522. In this second embodiment, the impact-absorbing member 530 has a slender shape that decreases in length in the height direction Z as it moves outward toward the width direction X. The impact-absorbing member 530 is elongated in the width direction X, and its length in the width direction X is greater than its length in the height direction Z.

[0231] (Detailed structural example of the second cap component)

[0232] The second cap member 532 is arranged adjacent to the side beam inner member 522.

[0233] The second cap component 532 includes a pair of second flanges 532a and 532b, a pair of base end side second ridge portions 532f and 532g, a pair of second longitudinal wall portions 532c and 532d, a pair of top end side second ridge portions 532h and 532i, and a second top plate portion 532e.

[0234] The pair of second flanges 532a and 532b of the second cap member 532 are the portions that are joined to the side beam 515. In this embodiment, they are joined to the inner surface of the side wall 723 of the inner member 522 of the side beam by the joining method described above. The second flanges 532a and 532b may not be directly joined to the inner member 522 of the side beam, but may be joined to the inner member 522 of the side beam via other members such as supplementary members (reinforcing members).

[0235] Thus, the second flanges 532a and 532b of the impact-absorbing member 530 are joined to the inner member 522 of the side beam. According to this structure, in the event of a side impact, the impact load acting on the first top plate portion 531e can be transferred from the inner member 522 of the side beam to the floor beams 516 and 517 with high transmission efficiency. Therefore, through the cooperation of the side beam 515, the impact-absorbing member 530, and the floor beams 516 and 517, more impact energy can be absorbed. As a result, the impact of the side beam 515 onto the battery casing 600 during a side impact can be suppressed.

[0236] The lengths of the second flanges 532a and 532b are not particularly limited, but if they are shorter than the length of the second top plate portion 532e, the total length of the second cap member 532 in the height direction Z can be shortened. On the other hand, if the lengths of the second flanges 532a and 532b are greater than the length of the second top plate portion 532e, the bonding strength between the second cap member 532 and the side beam 515 in the height direction Z can be further improved.

[0237] The upper second flange 532a extends upward from the upper second longitudinal wall portion 532c, and the lower second flange 532b extends downward from the lower second longitudinal wall portion 532d. These second flanges 532a and 532b are separate from each other, and the second cap member 532 has a shape that opens inward toward the side beam inner member 522 in the width direction X. Thus, preferably, the impact absorbing member 530 and the side beam inner member 522 are joined only at the second flanges 532a and 532b, and no other part of the impact absorbing member 530 is disposed between the second flanges 532a and 532b in the height direction Z. With such a structure, the impact absorbing member 530 can be made lighter. Furthermore, when spot welding the side beam inner member 522 and the impact absorbing member 530, the second flanges 532a and 532b, which are positioned outside the pair of second longitudinal wall portions 532c and 532d in the height direction Z, can be clamped and welded using a welding machine. Thus, in this embodiment, there are outwardly facing second flanges 532a and 532b positioned outside the pair of second longitudinal wall portions 532c and 532d in the height direction Z. The lower end of the upper second flange 532a and the upper end of the lower second flange 532b are connected to the second longitudinal wall portions 532c and 532d via the base end side second ridge portions 532f and 532g.

[0238] The second ridge portions 532f and 532g on the base end side are curved in an arc shape in the cross section, which has the function of improving the impact energy absorption of the second cap member 532 during impact absorption. The radius of curvature of the second ridge portions 532f and 532g on the base end side in the cross section is in the range of several mm to tens of mm.

[0239] The pair of second longitudinal wall portions 532c and 532d of the second cap member 532 are arranged along the width direction X, and the spacing between the pair of second longitudinal wall portions 532c and 532d increases as they extend toward the side beam inner member 522. With this arrangement of the pair of second longitudinal wall portions 532c and 532d, the second cap member 532 can evenly bear the impact load acting inward from the side beam outer member 521 in the width direction X. Therefore, in the event of a side collision, the amount of impact energy absorbed by the impact absorbing member 530 can be further improved. Furthermore, the pair of second longitudinal wall portions 532c and 532d can also be arranged parallel (horizontally) to the width direction X, or the spacing between the pair of second longitudinal wall portions 532c and 532d can narrow as they extend toward the side beam inner member 522.

[0240] The top end of the upper second longitudinal wall portion 532c and the top end of the lower second longitudinal wall portion 532d are connected to the second top plate portion 532e via the top side second ridge portions 532h and 532i.

[0241] The second ridge sections 532h and 532i on the top side are curved in an arc shape in the cross section, which has the function of improving the impact energy absorption of the second cap member 532 during impact absorption. The radius of curvature of the second ridge sections 532h and 532i on the top side in the cross section is in the range of several mm to tens of mm.

[0242] The second top plate portion 532e suppresses out-of-plane deformation such as the pair of second longitudinal wall portions 532c and 532d connected to it tilting inwards. In this embodiment, the second top plate portion 532e is arranged parallel to the first top plate portion 531e of the first cap member 531. The second top plate portion 532e connects the pair of second longitudinal wall portions 532c and 532d. Furthermore, the second top plate portion 532e is joined to the pair of first flanges 531a and 531b by the joining method described above.

[0243] Furthermore, in this embodiment, the second top plate portion 532e is parallel to the height direction Z. With such a structure, in the event of a side impact, the second top plate portion 532e can evenly bear the horizontal load acting on it in the height direction Z via the side wall 713 of the side beam outer member 521 and the first cap member 531. This further increases the collapse amount of the second cap member 532, allowing it to absorb more impact energy.

[0244] The second top plate portion 532e is disposed in the middle portion of the impact-absorbing member 530 in the standing direction (width direction X) of the pair of second longitudinal wall portions 532c and 532d. By having the second top plate portion 532e, the outer portion and the inner portion of the second top plate portion 532e in the impact-absorbing member 530 can be shortened respectively in the width direction X. As a result, the out-of-plane deformation of the pair of second longitudinal wall portions 532c and 532d and the pair of first longitudinal wall portions 531c and 531d (described later) of the first cap member 531 during a side impact can be suppressed, further increasing the energy absorption based on wall buckling motion.

[0245] The second top plate portion 532e is positioned relative to the inner member 522 of the side beam, which is offset from the outer member 521. This allows for a further increase in the length (height H531) of the first cap member 531. Consequently, in a side impact, the length (impact absorption stroke) of the first cap member 531 that can absorb impact by collapsing in the width direction X can be increased. Furthermore, the space within the second cap member 532 can be reduced. As a result, in a side impact, the out-of-plane deformation of the pair of second longitudinal wall portions 532c and 532d of the second cap member 532 can be suppressed. Moreover, in a side impact, by first collapsing the first cap member 531 and then the second cap member 532, impact loads from the width direction X can be absorbed sequentially from the members positioned on the outer side in the width direction X. By performing such a smooth impact absorption action, the impact energy absorption efficiency of the impact absorbing member 530 can be improved.

[0246] (Detailed structural example of the first cap component)

[0247] The first cap member 531 is positioned relative to the outer member 521 of the side beam and the inner member 522 of the side beam. This arrangement of the second cap member 532 and the first cap member 531 allows the first cap member 531 to collapse first and absorb impact energy during a side collision.

[0248] The first cap member 531 has a pair of first flanges 531a and 531b, a pair of base end side first ridge portions 531f and 531g, a pair of first longitudinal wall portions 531c and 531d, a pair of top end side first ridge portions 531h and 531i, and a first top plate portion 531e.

[0249] The first flanges 531a and 531b of the first cap member 531 are joined to the outer side of the second top plate portion 532e of the second cap member 532 by the joining method described above. The first flanges 531a and 531b may not be directly joined to the second top plate portion 532e, but may be joined to the second top plate portion 532e via a supplement (reinforcing member).

[0250] The lengths of the first flanges 531a and 531b are not particularly limited, but it is preferable that they do not extend from the second top plate portion 532e in the height direction Z, in order to make the first cap member 531 lightweight. Furthermore, the end faces 531j and 531k of the first flanges 531a and 531b face the height direction Z and do not oppose the second cap member 532 in the height direction Z. Alternatively, the first flanges 531a and 531b may contact the second top plate portion 532e of the second cap member 532, but not the second ridge portions 532h and 532i on the top side. By configuring the first flanges 531a and 531b as described above, the longitudinal wall portions 531c and 531d of the first cap member 531 are arranged offset from the area obtained by extending the longitudinal wall portions 532c and 532d of the second cap member 532 in the length direction of these longitudinal wall portions 532c and 532d. With this arrangement of the first cap member 531, when an impact load is applied to the first cap member 531, the first flanges 531a and 531b can firmly support the longitudinal wall portions 531c and 531d. As a result, more impact energy can be absorbed by promoting the deformation of the longitudinal wall portions 531c and 531d between the base end side first ridge portions 531f and 531g and the top end side first ridge portions 531h and 531i.

[0251] The upper first flange 531a extends upward from the upper first longitudinal wall portion 531c, and the lower first flange 531b extends downward from the lower first longitudinal wall portion 531d. These first flanges 531a and 531b are separate from each other, and the second cap member 532 has a shape that opens inward to the side beam inner member 522 in the width direction X. Thus, preferably, the first cap member 531 joins only at the second top plate portion 532e of the second cap member 532, and no other part of the impact absorbing member 530 is disposed between the first flanges 531a and 531b in the height direction Z. With such a structure, the impact absorbing member 530 can be made lighter. Furthermore, when spot welding the second cap member 532 and the first cap member 531, the first flanges 531a and 531b and the second top plate portion 532e, which are located on the outer side of the pair of first longitudinal wall portions 531c and 531d in the height direction Z, can be welded using a welding machine. Thus, in this embodiment, there are outwardly facing first flanges 531a and 531b located on the outer side of the pair of first longitudinal wall portions 531c and 531d in the height direction Z. The lower end of the upper first flange 531a and the upper end of the lower first flange 531b are connected to the first longitudinal wall portions 531c and 531d via the base end side first ridge portions 531f and 531g.

[0252] The first ridge portions 531f and 531g on the base end side are curved in an arc shape in the cross section, which has the function of improving the impact energy absorption of the first cap member 531 during impact absorption. The radius of curvature of the first ridge portions 531f and 531g on the base end side in the cross section is in the range of several mm to tens of mm. The radius of curvature of the first ridge portions 531f and 531g on the base end side can be the same as, smaller than, or larger than the radius of curvature of the second ridge portions 532f and 532g on the base end side of the second cap member 532.

[0253] The pair of first longitudinal wall portions 531c and 531d of the first cap member 531 are arranged along the width direction X, and the spacing between the pair of first longitudinal wall portions 531c and 531d increases as they extend toward the side beam inner member 522. This arrangement of the pair of first longitudinal wall portions 531c and 531d allows impact loads acting from the side beam outer member 521 toward the inner side in the width direction X to be evenly transferred from the first cap member 531 to the second cap member 532. Therefore, the impact energy absorption of the impact absorbing member 530 can be further improved during a side collision. Furthermore, the pair of first longitudinal wall portions 531c and 531d can be arranged either parallel (horizontally) to the width direction X, or the spacing between the pair of first longitudinal wall portions 531c and 531d can narrow as they extend toward the side beam inner member 522.

[0254] The top end of the upper first longitudinal wall portion 531c and the top end of the lower first longitudinal wall portion 531d are connected to the first top plate portion 531e via the top side first ridge portions 531h and 531i.

[0255] The first edge portions 531h and 531i on the top side are curved in an arc shape in the cross section, which has the function of improving the impact energy absorption of the first cap member 531 during impact absorption. The radius of curvature of the first edge portions 531h and 531i on the top side in the cross section is in the range of several mm to tens of mm.

[0256] The first top plate portion 531e and the first longitudinal wall portions 531c and 531d of the first cap member 531 are the first parts of the impact-absorbing member 530 to bear the impact load during a side collision.

[0257] In this embodiment, the first top plate portion 531e is positioned relative to the outer member 521 of the side beam and the inner member 522 of the side beam. This ensures sufficient length of the impact-absorbing member 530 in the width direction X. Consequently, in the event of a side impact, the length of the impact-absorbing member 530 that can absorb the impact by collapsing in the width direction X (impact absorption stroke) can be increased.

[0258] In this embodiment, the first top plate portion 531e contacts the side wall 713 of the side beam outer member 521, but does not engage with the side wall 713 of the side beam outer member 21.

[0259] With this preferred structure, it is easy to install the impact-absorbing member 530 within the side beam 515. This is because it eliminates the need to join the first top plate portion 531e to the side wall 713 of the outer member 521 of the side beam. If the first top plate portion 531e were joined to the side wall 713 of the outer member 521 of the side beam by welding, a welding machine would need to be clamped at both the first top plate portion 531e and the side wall 713. Therefore, installing the impact-absorbing member 530 within the side beam 515 is time-consuming. This time-consuming process applies regardless of whether the welding is spot welding, laser welding, or adhesive-based bonding.

[0260] Furthermore, with this preferred structure, in a side collision, the impact-absorbing member 530 can undergo a two-stage collapse by sequentially compressing through two closed section portions 561 and 562 while minimizing deformation of the outer member 521 of the side beam, thus improving the impact energy absorption efficiency. In other words, in a side collision, the impact-absorbing member 530 can deform and absorb the impact while being less affected by the deformation of the outer member 521 of the side beam. Therefore, the impact absorption performance of the impact-absorbing member 530 can be utilized more effectively.

[0261] Furthermore, the first top plate portion 531e can also be separated from the side wall 713 of the outer member 521 of the side beam to a degree that it does not come into contact with the vehicle even under vibration during driving. In this way, if the first top plate portion 531e separates from the outer member 521 of the side beam, in the event of a relatively minor side impact, deformation of the components caused by impact transmission from the outer member 521 of the side beam to the impact-absorbing member 530 and the inner member 522 of the side beam can be suppressed. In the event of a relatively minor side impact, the impact acts on the outer member 521 of the side beam, but this impact is not transmitted from the outer member 521 of the side beam to the impact-absorbing member 530. Therefore, impact transmission to the inner member 522 of the side beam via the impact-absorbing member 530 is avoided. In this case, the deformation of the side beam 515 is less, thus suppressing the reduction in vehicle driving performance (straight-line performance, etc.). Furthermore, during vehicle repair, the sidewall 713 of the outer side beam component 521 needs to be repaired. On the other hand, the impact-absorbing component 530 and the inner side beam component 522 can be left unrepaired, further reducing the time and cost of vehicle maintenance. Moreover, in the event of a large side collision, the impact energy can be efficiently absorbed by the deformation of the impact-absorbing component 530 and the inner side beam component 522 through the impact-absorbing component 530 to the inner side beam component 522, via the impact transmission from the outer side beam component 521 to the inner side beam component 522.

[0262] In terms of utilizing the entire first top plate portion 531e to bear the impact load from the side wall 713 of the side beam outer member 521, it is preferable that the first top plate portion 531e is arranged parallel to the side wall 713. The first top plate portion 531e connects a pair of first longitudinal wall portions 531c and 531d. The first top plate portion 531e is the shortest part in the height direction Z of the impact absorbing member 530. In terms of improving the efficiency of absorbing impact energy acting in the width direction X during a side collision, it is preferable that the first top plate portion 531e is arranged parallel to the second top plate portion 532e.

[0263] According to the above structure, the pair of longitudinal wall portions 531c and 531d (a pair of first parts) of the first cap member 531 cooperate with the pair of longitudinal wall portions 532c and 532d (a pair of second parts) of the second cap member 532 to form the pair of longitudinal wall portions 545 and 546 of the cap-shaped portion 540 of the impact absorbing member 530.

[0264] (Structural examples of the first closed section and the second closed section)

[0265] According to the above structure, the second closed section portion 562 is formed by a second top plate portion 532e, a pair of top-side second ridge portions 532h and 532i, a pair of second longitudinal wall portions 532c and 532d, a pair of base-side second ridge portions 532f and 532g, a pair of second flanges 532a and 532b, and the side wall 723 of the side beam inner member 522. Furthermore, the first closed section portion 561 is formed by a first top plate portion 531e, a pair of top-side first ridge portions 531h and 531i, a pair of first longitudinal wall portions 531c and 531d, a pair of base-side first ridge portions 531f and 531g, a pair of first flanges 531a and 531b, and the second top plate portion 532e.

[0266] In this second embodiment, the second longitudinal wall portions 532c and 532d of the second cap member 532 are not arranged in a straight line with the corresponding first longitudinal wall portions 531c and 531d of the first cap member 531. With such a stepped straight-line layout, in the event of a side collision, the multiple ridge portions 531f~531i and 532f~532i can absorb the impact load acting on the impact absorption member 530 from the first top plate portion 531e.

[0267] (Example of materials for impact-absorbing components)

[0268] Next, the material and other details of the impact-absorbing component 530 will be explained.

[0269] When the impact-absorbing component 530 is made of steel sheet, iron, which is cheaper than aluminum, can be used, thus reducing the manufacturing cost of the body 501.

[0270] In this second embodiment, the second cap member 532 and the first cap member 531 of the impact absorbing member 530 are each formed of steel plate. The tensile strength of each cap member 531 and 532 can be 590 MPa to 2.5 GPa. More specifically, the lower limit of the tensile strength of each cap member 531 and 532 can also be 780 MPa, 980 MPa, 1.3 GPa, 1.5 GPa, 1.7 GPa, 2.0 GPa, or 2.3 GPa. Furthermore, the upper limit of the tensile strength of each cap member 531 and 532 can also be 1.5 GPa, 1.7 GPa, 2.0 GPa, or 2.3 GPa.

[0271] Tensile strength can be evaluated according to JIS Z 2241:2011. As a test piece for determining tensile strength, test piece No. 5 of JIS Z 2241:2011 can be used as an example. As for the sampling location of the tensile test piece, for example, the central portion of a pair of second longitudinal wall portions 532c and 532d of the second cap member 532, and the central portion of a pair of first longitudinal wall portions 531c and 531d of the first cap member 531 can be used as examples.

[0272] As for Vickers hardness HV1 and HV2 equivalent to the tensile strength of the aforementioned cap components 531 and 532, examples of Vickers hardness HV1 and HV2 for each cap component 531 and 532 can be given. Examples of Vickers hardness HV1 and HV2 for each cap component 531 and 532 can be 240 to 780. The lower limit of Vickers hardness HV1 and HV2 for each cap component 531 and 532 can also be 180 corresponding to 590 MPa, 240 corresponding to 780 MPa, 300 HV corresponding to 980 MPa, 400 corresponding to 1.3 GPa, 460 corresponding to 1.5 GPa, 520 corresponding to 1.7 GPa, 620 corresponding to 2.0 GPa, or 710 corresponding to 2.3 GPa. In addition, the upper limit of the Vickers hardness HV1 and HV2 of each cap component 531 and 532 can also be 460 corresponding to 1.5GPa, 520 corresponding to 1.7GPa, 620 corresponding to 2.0GPa, 710 corresponding to 2.3GPa, or 780 corresponding to 2.5GPa.

[0273] The Vickers hardness of each cap component 531 and 532 can be measured as follows. Vickers hardness (HV1) "HV1" refers to the "hardness symbol" (JIS Z 2244-1:2020) when a Vickers hardness test is performed with a test force of 1 kgf (9.807 N). The Vickers hardness is measured as follows. First, a test specimen is cut from a flat plate portion such as the first top plate portion 531e of the first cap component 531 with the cut surface (test surface) parallel to the thickness direction of the flat plate portion. The specimen is then embedded in resin and the cut surface is ground. Then, at a depth of 1 / 4 of the plate thickness at the cut surface (test surface) from the surface of the test specimen, 10 points are measured at 0.5 mm intervals under a test force of 1 kgf (9.807 N), and the average value is taken.

[0274] The Vickers hardness (HV2) "HV2" is the value obtained by cutting a test specimen from a flat portion such as the second top plate portion 532e of the second cap member 532 instead of the first top plate portion 531e mentioned above and performing the above test.

[0275] In this second embodiment, the tensile strength TS1 (Vickers hardness HV1) of the first cap member 531 is set to be lower than the tensile strength TS2 (Vickers hardness HV2) of the second cap member 532 (TS1 < TS2). That is, the strength of the outer side member 521 of the impact absorbing member 530 is lower than the strength of the inner side member 522.

[0276] By setting this tensile strength, in a side impact, the first cap member 531 can begin to deform and absorb impact energy before the second cap member 532. Within the closed cross-sectional space 523, the first cap member 531, located on the side away from the battery housing 600 in the impact-absorbing member 530, deforms first, thereby delaying the deformation of the second cap member 532 on the side closer to the battery housing 600. In other words, the deformation of the second cap member 532 can be suppressed until the first cap member 531 is fully deformed. As a result, the amount of impact energy absorbed by the collapse of the first cap member 531 can be increased, and the contact between the inner member 522 of the side beam, which collapses together with the collapse of the second cap member 532, and the side wall 600b of the battery housing 600 can be suppressed. Moreover, the second cap member 532 is of high strength, thus further increasing the amount of impact energy absorbed by the second cap member 532.

[0277] The tensile strength TS2 (Vickers hardness HV2) of the second cap member 532 is preferably about 1.3 to 1.7 times the tensile strength TS1 (Vickers hardness HV1) of the first cap member 531, and can be exemplified as about 1.5 times. With this setting, the first cap member 531 can be crushed during a side impact, and the second cap member 532 can begin to crush after the first cap member 531 has fully collapsed. Furthermore, it can suppress the situation where cracks form in the first cap member 531 during a side impact due to significant collapse, thus reducing the impact energy absorption efficiency. As a more specific example, a structure can be illustrated by setting the tensile strength TS1 of the first cap member 531 to 980 MPa and the tensile strength TS2 of the second cap member 532 to 1.5 GPa. In this structure, compared to setting the tensile strengths TS1 and TS2 of each cap member 531 and 532 to be the same, the impact energy absorption value can be further improved.

[0278] (Example of plate thickness for impact-absorbing components)

[0279] The plate thickness of each cap member 531 and 532 can be 0.8 mm to 2.3 mm. The plate thickness of each cap member 531 and 532 can be the same or different, but from the viewpoint of lightweighting, a smaller plate thickness is preferred. In this second embodiment, the plate thickness t1 of the first cap member 531 is set to be smaller than the plate thickness t2 of the second cap member 532. The plate thickness t2 of the second cap member 532 is preferably about 1.3 to 1.7 times the plate thickness t1 of the first cap member 531, and can be about 1.5 times. By setting these plate thickness ratios t2 / t1 to the above range, the second cap member 532 can begin to collapse after the first cap member 531 has fully collapsed during a side impact. Examples of lower limits for the plate thicknesses t1 and t2 of cap components 531 and 532 include 0.8mm, 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2.0mm, and 2.2mm. Examples of upper limits for the plate thicknesses t1 and t2 of each cap component 531 and 532 include 1.8mm, 1.9mm, 2.0mm, 2.1mm, and 2.2mm.

[0280] (An example of the strength ratio and plate thickness ratio of a cap component)

[0281] The tensile strength ratio TS2 / TS1 of each cap component 531 and 532 can be set to 1.3 to 1.7 (e.g., 1.5) and the plate thickness ratio t2 / t1 can be set to 1, or the tensile strength ratio TS2 / TS1 of each cap component 531 and 532 can be set to 1 and the plate thickness ratio t2 / t1 can be set to 1.3 to 1.7 (e.g., 1.5).

[0282] The combination of the plate thicknesses t1 and t2 of each cap component 531 and 532 with the tensile strengths TS1 and TS2 can be set such that, in a side collision, the first cap component 531 begins to collapse before the second cap component 532, and the second cap component 532 collapses after the first cap component 531 has fully collapsed.

[0283] For the Vickers hardness HV1 and plate thickness t1 at the first cap member 531, and the Vickers hardness HV2 and plate thickness t2 at the second cap member 532, it is preferred that 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, and HV1×t1<HV2×t2.

[0284] By setting HV1 to 180 ≤ HV1, the strength of the first cap member 531 can be sufficiently ensured, thereby improving the impact energy absorption efficiency. Furthermore, by setting HV2 ≤ 780, cracking during deformation of the second cap member 532 can be suppressed, further improving impact energy absorption efficiency. Additionally, by setting 0.8 mm ≤ t1, the stiffness of the first cap member 531 can be sufficiently ensured, suppressing cracking in it. Furthermore, by setting t2 ≤ 2.3 mm, the second cap member 532 can be made lighter. Moreover, by setting HV1 × t1 < HV2 × t2, the following operation can be performed more reliably: in a side impact, the first cap member 531 begins to collapse before the second cap member 532, and the second cap member 532 begins to collapse after the first cap member 531 has fully collapsed.

[0285] Thus, the impact absorbing component 530 is formed by multiple cap components 531 and 532, so there is a high degree of freedom in distinguishing and using the Vickers hardness HV1 and HV2 of the multiple cap components 531 and 532, and in selecting the plate thickness t1 and t2.

[0286] (An example of the effect of the second embodiment)

[0287] With the above structure, in this second embodiment, the degree of freedom in setting the shape of the impact-absorbing member 530 can be further improved, and the side beam structure 514 and the lower structure 502 of the vehicle can achieve high side impact resistance performance.

[0288] In particular, in this embodiment, impact-absorbing members 530 are arranged on both sides (left and right sides) of the width direction X of the vehicle body 501, so that the impact-absorbing members 530 can absorb the impact energy regardless of whether a side collision occurs on the right or left side of the vehicle body 501.

[0289] Furthermore, the impact-absorbing member 530 disposed on the side of the battery housing 600 can absorb impact energy, thereby protecting the battery housing 600 and the battery 601 inside the battery housing 600.

[0290] [First variation of the second embodiment]

[0291] Figure 10 This is a schematic cross-sectional view showing the main parts of a first modification of the second embodiment of the present disclosure. In this embodiment, the second top plate portion 532e is positioned biased towards the side beam inner member 522, which is between the outer side beam member 521 and the inner side beam member 522. On the other hand, as... Figure 10 As shown, in the first variation of the second embodiment, the second top plate portion 532e is positioned at the side wall 713 of the side beam outer member 521, which is biased towards the side beam inner member 522.

[0292] Therefore, in the width direction X, the height H531 of the first cap member 531 is shorter than the height H532 of the second cap member 532.

[0293] In particular, in the first variation of the second embodiment, the second top plate portion 532e is located on the outer side of the width direction X, i.e., the flanges 711, 721 and 715, 725, which are the boundary between the outer side beam member 521 and the inner side beam member 522.

[0294] This arrangement increases the space between the second top plate portion 532e and the inner member 522 of the side beam (the space within the second cap member 532). As a result, in a side impact, the impact energy absorbed by the collapse of the pair of second longitudinal wall portions 532c and 532d can be increased. Moreover, in a side impact, by first collapsing the first cap member 531 and then the second cap member 532, the impact load from the width direction X can be absorbed sequentially from the members located on the outer side in the width direction X. By performing such a smooth impact absorption action, the impact absorption efficiency of the impact absorbing member 530 in absorbing impact energy can be improved.

[0295] [Second variation of the second embodiment]

[0296] Figure 11 This is a schematic cross-sectional view showing the main parts of a second variation of the second embodiment of this disclosure. In the second embodiment, the shape in which the first top plate portion 531e contacts the side beam 515 is mainly illustrated. On the other hand, it could also be, as... Figure 11 In the second variation, the first top plate portion 531e is fully separated from the side beam 515. More specifically, the first top plate portion 531e is adjacent to the side wall 713 of the side beam outer member 521, but is separated from the side wall 713.

[0297] With such a structure, vibration noise caused by the contact between the first top plate portion 531e and the outer member 521 of the side beam can be suppressed, and the impact load from the outer member 521 of the side beam, along with the collapse of the outer member 521, can be transferred to the impact absorbing member 530 during a side collision. Furthermore, the impact absorbing member 530 does not need to be joined to both the inner member 522 and the outer member 521 of the side beam, reducing the time required for installing the impact absorbing member 530 onto the side beam 515.

[0298] In terms of utilizing the first top plate portion 531e as a whole to bear the impact load from the side wall 713 of the side beam outer member 521, it is preferable that the first top plate portion 531e is arranged parallel to the side wall 713.

[0299] [Third variation of the second embodiment]

[0300] Figure 12 This is a schematic cross-sectional view showing the main parts of a third variation of the second embodiment of this disclosure. In the second embodiment, it has been described as an example where the second flanges 532a and 532b are only joined to the side wall 723 of the side beam inner member 522. On the other hand, it may also be as follows: Figure 12 As shown in the third modified example, the second flanges 532a and 532b are also joined to the portion of the side beam 515 other than the side wall 723.

[0301] In the third variation of the second embodiment, a pair of second flanges 532a and 532b are joined to the side wall 723 of the side beam inner member 522 and the upper wall 722 and lower wall 724, which are a pair of walls, by the joining method described above.

[0302] The second flanges 532a and 532b are respectively formed in the shape of the portion of the inner member 522 of the side beam opposite to the second flange 532a and 532b. In the third variation of the second embodiment, each second flange 532a and 532b is provided to be bent (bent) in the middle part in the height direction Z. The second flanges 532a and 532b only need to be joined to at least a portion of the side wall 723, the upper wall 722, and the lower wall 724. For example, they may not be joined to the connection portion (ridge portion) between the side wall 723 and the upper wall 722, or the connection portion (ridge portion) between the side wall 723 and the lower wall 724.

[0303] According to the structure of the third variation of the second embodiment, the second flanges 532a and 532b are joined not only to the side wall 723 of the side beam inner member 522, but also to the upper wall 722 and the lower wall 724. This further improves the bonding strength between the second cap member 532 and the side beam 515. As a result, even in a strong impact on the side beam 515 during a side collision, the second cap member 532 can be prevented from detaching from the side beam 515, and the impact absorption effect of the impact-absorbing member 530 can be performed more reliably.

[0304] [Fourth variation of the second embodiment]

[0305] Figure 13 This is a schematic cross-sectional view showing the main parts of the fourth modification of the second embodiment of this disclosure. In this embodiment, an example is described with the second top plate portion 532e parallel to the height direction Z (the side walls 713, 723 of the side beam 515). On the other hand, it may also be as follows: Figure 13 As shown, the second top plate portion 532e is arranged at an angle relative to the height direction Z (side walls 713, 723 of the side beam 515).

[0306] For example, it could also be, such as Figure 13 As shown, the second top plate portion 532e is inclined outward in the width direction X as it extends downward. Alternatively, the second top plate portion 532e may be inclined inward in the width direction X as it extends downward. The inclination angle θ of the second top plate portion 532e relative to the height direction Z is not particularly limited, but it is preferably 45 degrees or less for the purpose of more reliably withstanding the impact of a side collision using the second top plate portion 532e. The inclination angle θ may also be 30 degrees or less, or 15 degrees or less. In this case, it may also be as follows: Figure 13 As shown, the first top plate portion 531e and the second top plate portion 532e are arranged in parallel. Alternatively, the first top plate portion 531e may be inclined relative to the second top plate portion 532e. Alternatively, the first top plate portion 531e may be parallel to the side walls 713 and 723 of the side beam 515.

[0307] As explained above, in the fourth variation of the second embodiment, the second top plate portion 532e is inclined relative to the height direction. With this structure, for example, even if the side beam 515 collides obliquely with a column fixed to the ground, the second cap member can more reliably withstand the impact from the column. Furthermore, the height position of the first cap member 531 can be changed without altering the fixed positions of the second flanges 532a, 532b and the side beam 515. Thus, with minor design changes, the layout of the first cap member 531 can be altered, increasing the design freedom of the impact-absorbing member 530.

[0308] [Fifth variation of the second embodiment]

[0309] Figure 14 This is a schematic cross-sectional view showing the main parts of the fifth variation of the second embodiment of the present disclosure. In this embodiment, an example is described where the second top plate portion 532e has a flat shape in cross-section. Alternatively, it could be, as... Figure 14 As shown, in the cross section, the second top plate portion 532e has multiple ridge portions 541a, 541b, 541c, and 541d at the midpoint of the height direction Z, formed by the positional change in the width direction X.

[0310] In the fifth variation of the second embodiment, the second top plate portion 532e has a shape that is recessed inward toward the width direction X (recessed away from the first top plate portion 531e) by forming a reinforcing rib 541. The depth H541 of the reinforcing rib 541 is not particularly limited, but for example, it may be less than 1 / 2, less than 1 / 3, or less than 1 / 4 of the height H532 of the second cap member 532.

[0311] The reinforcing rib 541 is disposed, for example, at the central portion in the height direction Z of the second top plate portion 532e. The reinforcing rib 541 forms a recess (cap-shaped portion) in the cross section. The reinforcing rib 541 can be either symmetrical or asymmetrical in the height direction Z. The reinforcing rib 541 forms multiple (four in the fifth variation) ridge portions 541a, 541b, 541c, and 541d.

[0312] Each of the ridge sections 541a, 541b, 541c, and 541d is a curved section in the cross-section, which functions to increase the impact energy absorption of the second cap member 532 during impact absorption. The radius of curvature of each of the ridge sections 541a, 541b, 541c, and 541d in the cross-section is in the range of several millimeters to tens of millimeters.

[0313] As explained above, according to the structure of the fifth variation of the second embodiment, in the second cap member 532, in addition to the second ridge portions 532f, 532g, 532h, and 532i, there are also ridge portions 541a, 541b, 541c, and 541d formed by reinforcing ribs 541. Therefore, with more ridge portions in the second cap member 532, the impact energy absorption efficiency of the second cap member 532 during deformation can be further improved by the action of the multiple ridge portions 532f~532i and 541a~541d of the impact absorption member 530 during a side impact.

[0314] Furthermore, in the fifth variation of the second embodiment, an example was described where a reinforcing rib 541 with a recessed shape is provided in the second top plate portion 532e. However, this is not always the case. For example, the reinforcing rib may be in the second top plate portion 532e in a shape that protrudes toward the side beam outer member 521. In addition, the reinforcing rib may also be formed in a shape that protrudes toward the upper or lower side in a pair of second longitudinal wall portions 532c, 532d. Furthermore, the reinforcing rib may also be formed in the first cap member 531 in the first top plate portion 531e and protrude toward the inner or outer side in the width direction X.

[0315] Alternatively, the reinforcing ribs may be formed in a shape that protrudes upwards or downwards in one of the pair of first longitudinal wall portions 531c, 531d. More specifically, for example, it may be as shown in the accompanying drawings, which are a fifth variation of the second embodiment. Figure 15 As shown, in the first longitudinal wall portions 531c and 531d, a plurality of concave reinforcing ribs 542 extending from the base end side of the first cap member 531 toward the top end side are intermittently formed in the front-rear direction Y. Each reinforcing rib 542 extends from the first top plate portion 531e to the corresponding first flange 531a and 531b. Each reinforcing rib 542 is concave when viewed from the width direction X and has a plurality of (e.g., four) ridge portions 542a, 542b, 542c, and 542d. By providing such ridge portions 542a, 542b, 542c, and 542d, the absorption efficiency of impact energy until the first cap member 531 collapses can be further improved in the event of a side impact. Furthermore, such reinforcing ribs, similar to those of the reinforcing ribs 542, can also be formed in a pair of second longitudinal wall portions 532c and 532d of the second cap member 532.

[0316] [Sixth variation of the second embodiment]

[0317] Figure 16 This is a schematic cross-sectional view showing the main parts of the sixth modification of the second embodiment of the present disclosure. In the sixth modification of the second embodiment, in addition to the structure of the second embodiment, a second reinforcing member 552 is also provided in the impact absorbing member 530.

[0318] The second reinforcing member 552, also known as a supplement, may be formed of the same material as the second cap member 532 or the first cap member 531, or it may be formed of a different material than these cap members 531 and 532.

[0319] In the sixth variation of this second embodiment, the second reinforcing member 552 is a plate-shaped member joined to the second cap member 532. The second reinforcing member 552 can be formed either throughout the entire area where the second cap member 532 is located in the front-rear direction Y, or it can be formed locally. The second reinforcing member 552 is arranged such that it is surrounded by the second cap member 532. The second reinforcing member 552 includes: a second base 552a, which is joined along the inner side of the second top plate portion 532e; and a pair of second flanges 552b and 552c, which extend from both ends of the second base 552a in cross-section and along the inner sides of the pair of second longitudinal wall portions 532c and 532d. The second flanges 552b and 552c can also be joined to the inner sides of the pair of second longitudinal wall portions 532c and 532d. The joining method between the second reinforcing member 552 and the second cap member 532 is the same as the joining method described above.

[0320] As explained above, the second top plate portion 532e can be strengthened by providing the second reinforcing member 552. Therefore, the cooperation between the second top plate portion 532e and the second reinforcing member 552 can suppress out-of-plane deformation of the pair of second longitudinal wall portions 532c and 532d. Thus, in the event of a side impact, the impact energy absorption effect of the second cap member 532 can be more reliably utilized. Furthermore, in the sixth variation of this second embodiment, a structure in which the second reinforcing member 552 is located along the inner side of the second top plate portion 532e in the width direction X has been described as an example, but this is not necessary. The second reinforcing member 552 may also be located along the outer side of the second top plate portion 532e in the width direction X. Additionally, a plate-shaped reinforcing member similar to the second reinforcing member 552 may be arranged along the upper or lower surface of at least one of the second longitudinal wall portions 532c and 532d.

[0321] Alternatively, it could be, as in the sixth variation of the second embodiment. Figure 17As shown, a first reinforcing member 551 is disposed on the first cap member 531. The first reinforcing member 551, also called a supplement, can be formed of the same material as the second cap member 532 or the first cap member 531, or it can be formed of a different material than these cap members 531 and 532. The first reinforcing member 551 is a plate-like member joined to the first cap member 531. The first reinforcing member 551 can be formed either throughout the entire area where the first cap member 531 is located in the front-rear direction Y, or it can be formed locally. The first reinforcing member 551 is disposed in a manner surrounded by the first cap member 531. The first reinforcing member 551 includes: a first base 551a, which joins along the inner surface of the first top plate portion 531e; and a pair of first flanges 551b and 551c, which extend from both ends of the first base 551a in cross-section and along the inner surfaces of a pair of first longitudinal wall portions 531c and 531d. The first flanges 551b and 551c may also be joined to the inner surfaces of the pair of first longitudinal wall portions 531c and 531d. The joining method between the first reinforcing member 551 and the first cap member 531 is the same as the joining method described above. Furthermore, in this modified example, the structure in which the first reinforcing member 551 is positioned along the inner side of the first top plate portion 531e in the width direction X is described as an example, but this is not always the case. The first reinforcing member 551 may also be positioned along the outer side of the first top plate portion 531e in the width direction X. In addition, a plate-shaped reinforcing member similar to the first reinforcing member 551 may be arranged along the upper or lower surface of at least one of the first longitudinal wall portions 531c and 531d.

[0322] As explained above, the first top plate portion 531e is strengthened by providing the first reinforcing member 551. Therefore, the cooperation between the first top plate portion 531e and the first reinforcing member 551 can suppress out-of-plane deformation of the pair of first longitudinal wall portions 531c and 531d. Consequently, the impact energy absorption effect of the first cap member 531 can be more reliably utilized in the event of a side impact.

[0323] Alternatively, either the first reinforcing member 551 or the second reinforcing member 552 may be omitted. Furthermore, the second reinforcing member 552 may also be separated from the second top plate portion 532e. In this case, the second cap member 532 has two closed-section portions divided by the second reinforcing member 551, which can further improve the impact energy absorption efficiency during a side impact. Alternatively, the first reinforcing member 551 may also be separated from the first top plate portion 531e. In this case, the first cap member 531 has two closed-section portions divided by the first reinforcing member 551, which can further improve the impact energy absorption efficiency during a side impact.

[0324] [Seventh variation of the second embodiment]

[0325] Figure 18 This is a schematic cross-sectional view showing the main parts of the seventh variation of the second embodiment of the present disclosure. In this embodiment, a structure is shown in which the interval between the first longitudinal wall portions 531c and 531d of the first cap member 531 continuously narrows as it extends outward toward the width direction X. On the other hand, in the seventh variation of the second embodiment, the first longitudinal wall portions 531c and 531d of the first cap member 531 are integrally formed in cross-section into a shape that narrows midway.

[0326] A pair of first longitudinal wall portions 531c and 531d include base end side portions 531c1 and 531d1, ridge portion 531c2 and 531d2 connected to the base end side portions 531c1 and 531d1, and top end side portions 531c3 and 531d3 connected to the base end side portions 531c1 and 531d1 via the ridge portion 531c2 and 531d2.

[0327] The base end sides 531c1 and 531d1 become narrower as they extend outward in the width direction X. The ridge portions 531c2 and 531d2 are curved portions located midway along the width direction X of the first cap member 531. The top end sides 531c3 and 531d3 become wider as they extend outward in the width direction X.

[0328] As explained above, according to the seventh variation of the second embodiment, the first cap member 531, in addition to the first ridge portions 531f, 531g, 531h, and 531i, also has ridge portions 531c2 and 531d2. Therefore, with more ridge portions in the first cap member 531, the impact energy absorption efficiency during deformation of the first cap member 531 can be further improved by the action of the multiple ridge portions of the impact absorption member 530 during a side impact. Furthermore, if the first cap member 531 collapses during a side impact, deformation occurs such that the ridge portions 531c2 and 531d2 come into contact with each other, thus forming two closed-section portions in the first cap member 531, with the contact portion of the ridge portions 531c2 and 531d2 as the boundary. Therefore, the number of closed-section portions in the first cap member 531 increases, resulting in a further improvement in the impact energy absorption efficiency. Furthermore, by changing the position of the ridge portions 531c2 and 531d2 in the width direction X, the deformation shape of the first cap member 531 can be adjusted during a side collision.

[0329] [Eighth variation of the second embodiment]

[0330] Figure 19This is a schematic cross-sectional view showing the main parts of the eighth variation of the second embodiment of this disclosure. In this embodiment, an example is described using a structure in which the second flanges 532a, 532b and the first flanges 531a, 531b extend outward in the height direction Z relative to the corresponding closed section portions 562, 561. However, this is not always the case. It could also be as follows: Figure 19 As shown, for example, the second flanges 532a and 532b are arranged toward the inside of the second closed section portion 562. Alternatively, the first flanges 531a and 531b may be arranged toward the inside of the first closed section portion 561.

[0331] [Ninth variation of the second embodiment]

[0332] Figure 20 This is a schematic cross-sectional view showing the main part of the ninth variation of the second embodiment of this disclosure. In this embodiment, an example of an impact-absorbing member 530 formed using two cap members 531 and 532 has been described. However, this is not always the case. For example, the impact-absorbing member 530 may also be formed by n (n is a natural number of 3 or more) cap members.

[0333] In the ninth variation of the second embodiment, the impact-absorbing member 530 is described as an example, consisting of three cap members 531, 532, and 533. That is, in the ninth variation of the second embodiment, the impact-absorbing member 530 includes a third cap member 533 (the nth cap member) in addition to the second cap member 532 and the first cap member 531.

[0334] The first top plate portion 531e of the first cap member 531 is separated from the outer member of the side beam 521 in the width direction X. The height H533 of the third cap member 533 (the length of the third cap member 533 in the width direction X) is not particularly limited, and can be appropriately set according to the height H532 of the second cap member 532 and the height H531 of the first cap member 531.

[0335] The third cap member 533 has: a pair of third flanges 533a and 533b that engage with the first top plate portion 531e; a pair of third longitudinal wall portions 533c and 533d that extend from the pair of third flanges 533a and 533b; and a third top plate portion 533e that connects the pair of third longitudinal wall portions 533c and 533d.

[0336] Furthermore, in this modified example, the third cap member 533 has a pair of base end side third ridge portions 533f and 533g and a pair of top end side third ridge portions 533h and 533i.

[0337] A pair of third flanges 533a and 533b are joined to the first top plate portion 531e of the first cap member 531 by the joining method described above. The third flanges 533a and 533b may also be joined to the first top plate portion 531e not directly, but via a supplement (reinforcing member).

[0338] The lengths of the third flanges 533a and 533b are not particularly limited, but it is preferable that they do not extend from the first top plate portion 531e in the height direction Z in order to make the third cap member 533 lightweight. Furthermore, the end faces 533j and 531k of the third flanges 533a and 533b face the height direction Z and are not opposite to the first cap member 531 in the height direction Z. Alternatively, the third flanges 533a and 533b may contact the first top plate portion 531e of the first cap member 531, but not the first ridge portions 531h and 531i on the top side. By configuring the third flanges 533a and 533b as described above, the longitudinal wall portions 533c and 533d of the third cap member 533 are arranged offset from the area obtained by extending the longitudinal wall portions 531c and 531d of the first cap member 531 in the length direction of these longitudinal wall portions 531c and 531d. With this arrangement of the third cap member 533, when an impact load is applied to the third cap member 533, the third flanges 533a and 533b can firmly support the longitudinal wall portions 533c and 533d. As a result, more impact energy can be absorbed by promoting the deformation of the longitudinal wall portions 533c and 533d between the third ridge portions 533f and 533g on the base end side and the third ridge portions 533h and 533i on the top end side.

[0339] The upper third flange 533a extends upward from the upper third longitudinal wall portion 533c, and the lower third flange 533b extends downward from the lower third longitudinal wall portion 533d. These third flanges 533a and 533b are separate from each other, and the third cap member 533 has a shape that opens inward to the side beam inner member 522 in the width direction X. Thus, preferably, the third cap member 533 is joined only at the first top plate portion 531e of the first cap member 531, and no other part of the impact absorbing member 530 is arranged between the third flanges 533a and 533b in the height direction Z. With such a structure, the impact absorbing member 530 can be made lighter. Furthermore, when spot welding the first cap member 531 and the third cap member 533, the third flanges 533a and 533b and the first top plate portion 531e, which are positioned outside the pair of third longitudinal wall portions 533c and 533d in the height direction Z, can be welded using a welding machine. Thus, in the ninth variation of this second embodiment, there are outwardly facing third flanges 533a and 533b positioned outside the pair of third longitudinal wall portions 533c and 533d in the height direction Z. The lower end of the upper third flange 533a and the upper end of the lower third flange 533b are connected to the third longitudinal wall portions 533c and 533d via the base end side third ridge portions 533f and 533g.

[0340] The third ridge portions 533f and 533g on the base end side are curved in an arc shape in the cross section, which has the function of improving the impact energy absorption of the third cap member 533 during impact absorption. The radius of curvature of the third ridge portions 533f and 533g on the base end side in the cross section is in the range of several mm to tens of mm. The radius of curvature of the third ridge portions 533f and 533g on the base end side can be the same as, smaller than, or larger than the radius of curvature of the first ridge portions 531f and 531g on the base end side of the first cap member 531.

[0341] The pair of third longitudinal wall portions 533c and 533d of the third cap member 533 are arranged along the width direction X, and the spacing between the pair of third longitudinal wall portions 533c and 533d increases as they extend toward the side beam inner member 522. With this arrangement of the pair of third longitudinal wall portions 533c and 533d, the third cap member 533 can evenly bear the impact load acting inward from the side beam outer member 521 in the width direction X. Therefore, the impact energy absorption of the impact absorbing member 530 can be further improved during a side collision. Furthermore, the pair of third longitudinal wall portions 533c and 533d can also be arranged parallel (horizontally) to the width direction X, or the spacing between the pair of third longitudinal wall portions 533c and 533d can narrow as they extend toward the side beam inner member 522.

[0342] The upper third longitudinal wall portion 533c and the lower third longitudinal wall portion 533d are connected to the third top plate portion 533e via the top third ridge portion 533h and 533i.

[0343] The third ridge section 533h and 533i on the top side are curved in an arc shape in the cross section, which has the function of improving the impact energy absorption of the third cap member 533 during impact absorption. The radius of curvature of the third ridge section 533h and 533i on the top side in the cross section is in the range of several mm to tens of mm.

[0344] The third top plate portion 533e is the first part of the impact-absorbing member 530 to bear the impact load during a side collision. The third top plate portion 533e suppresses out-of-plane deformation such as the pair of third longitudinal wall portions 533c and 533d connected to the third top plate portion 533e tilting inwards towards these third longitudinal wall portions 533c and 533d.

[0345] In this embodiment, the third top plate portion 533e contacts the side wall 713 of the side beam outer member 521, but does not join the side wall 713 of the side beam outer member 521.

[0346] With this preferred structure, it is easy to install the impact-absorbing member 530 within the side beam 515. This is because it eliminates the need to join the third top plate portion 533e to the side wall 713 of the outer member 521 of the side beam. If the third top plate portion 533e were joined to the side wall 713 of the outer member 521 of the side beam by welding, a welding machine would need to be clamped at both the third top plate portion 533e and the side wall 713. Therefore, installing the impact-absorbing member 530 within the side beam 515 is time-consuming. This time-consuming process applies regardless of whether the welding is spot welding or laser welding.

[0347] Furthermore, with this preferred structure, in a side collision, the impact-absorbing member 530 can undergo three-stage collapse by sequentially compressing through three closed section portions 563, 561, and 562 while minimizing the impact of deformation of the outer member 521 of the side beam. This improves the impact energy absorption efficiency. In other words, in a side collision, the impact-absorbing member 530 can deform and absorb the impact while being less affected by the deformation of the outer member 521 of the side beam. Therefore, the impact absorption performance of the impact-absorbing member 530 can be utilized more effectively.

[0348] Furthermore, the third top plate portion 533e can also be separated from the side wall 713 of the side beam outer member 521 to a degree or sufficient degree so that it does not come into contact with the vehicle under vibration during driving.

[0349] In this way, if the top plate portion 533e separates from the outer side beam member 521, deformation of the components caused by impact transmission from the outer side beam member 521 to the impact-absorbing member 530 and the inner side beam member 522 can be suppressed in the event of a relatively minor side collision. In a relatively minor side collision, the impact acts on the outer side beam member 521, but the amount of impact transmitted from the outer side beam member 521 to the impact-absorbing member 530 is minimal. Therefore, the impact transmission to the inner side beam member 522 via the impact-absorbing member 530 is less. Under such circumstances, the deformation of the side beam 515 is less, thus suppressing the reduction in vehicle handling performance (straight-line performance, etc.). Furthermore, when repairing the vehicle, the sidewall 713 of the outer side beam member 521 needs to be repaired, while the impact-absorbing member 530 and the inner side beam member 522 do not need to be repaired, further reducing the time and cost of vehicle maintenance. On the other hand, when a vehicle is involved in a large side collision, the impact energy can be efficiently absorbed by the deformation of the impact absorption member 530 and the inner member 522 of the side beam through the impact transmission from the outer member 521 of the side beam to the inner member 522 of the side beam via the impact absorption member 530.

[0350] In terms of utilizing the entire third top plate portion 533e to bear the impact load from the side wall 713 of the side beam outer member 521, it is preferable that the third top plate portion 533e is arranged parallel to the side wall 713. The third top plate portion 533e connects a pair of third longitudinal wall portions 533c and 533d. In terms of improving the efficiency of absorbing impact energy acting in the width direction X during a side collision, it is preferable that the third top plate portion 533e is arranged parallel to the second top plate portion 532e and the first top plate portion 531e.

[0351] According to the above structure, the pair of longitudinal wall portions 531c and 531d (a pair of first parts) of the first cap member 531, the pair of longitudinal wall portions 532c and 532d (a pair of second parts) of the second cap member 532, and the pair of longitudinal wall portions 533c and 533d (a pair of third parts) of the third cap member 533 cooperate to form the pair of longitudinal wall portions 545 and 546 of the cap-shaped portion 540 of the impact absorbing member 530.

[0352] Thus, in the ninth variation of this second embodiment, the impact-absorbing member 530 has an nth (n is a natural number of 3 or more) cap member formed in a cap shape in cross-section. Furthermore, the nth cap member (the third cap member 533) includes a pair of nth flanges (the third flanges 533a and 533b), a pair of nth longitudinal wall portions (the third longitudinal wall portions 533c and 533d) extending from the pair of nth flanges, and an nth top plate portion (the third top plate portion 533e) connecting the pair of nth longitudinal wall portions. Moreover, each cap member (cap members 531-533) is arranged along the width direction X, and in adjacent cap members (the second cap member 532 and the first cap member 531; the first cap member 531 and the third cap member 533), the top plate portion engages with a pair of flanges.

[0353] Thus, the impact-absorbing member 530 is formed by three or more cap members, allowing for the provision of more ridge portions. Consequently, during a side impact, the multiple ridge portions of the impact-absorbing member 530 enhance the impact energy absorption efficiency during the deformation of the closed-section shape of the second cap member 532, the first cap member 531, and the third cap member 533. In particular, the third cap member 533, which bears the impact load first, has multiple ridge portions, further increasing the amount of impact energy absorbed when the third cap member 533 collapses. As a result, the impact energy absorption efficiency of the impact-absorbing member 530 is improved. This allows for a lighter impact-absorbing member 530 while increasing its impact energy absorption capacity, further improving the weight efficiency of impact energy absorption. Furthermore, by adjusting the shape of each cap member 531 to 533, the onset time and mode of deformation for each cap member 531 to 533 during a side impact can be set. Therefore, the impact absorption action of the impact absorbing member 530 during a side collision can be set according to the characteristics of the vehicle (the presence or absence of the battery housing 600, the layout of the battery housing 600, etc.). As a result, higher side collision resistance performance can be achieved for the vehicle. Moreover, since the impact absorbing member 530 is formed by multiple members (in this embodiment, the second cap member 532, the first cap member 531, and the third cap member 533), the freedom of shape setting can be further improved compared to the case where the impact absorbing member 530 is formed by a single member.

[0354] Furthermore, in the ninth variation of this second embodiment, an example was described where the impact-absorbing member 530 is formed by three cap members 531, 532, and 533. However, the impact-absorbing member 530 may also be formed by four or more cap members. In this case, the multiple cap members are arranged along the width direction X, and in adjacent cap members, the top plate portion engages with a pair of flanges. In this case, it is also preferable that the length of the impact-absorbing member 530 in the height direction Z gradually decreases as it extends outward toward the width direction X. As a result, impact energy can be efficiently absorbed by the collapse of the impact-absorbing member 530.

[0355] [Tenth variation of the second embodiment]

[0356] Figure 21 This is a schematic cross-sectional view showing the main parts of the tenth variation of the second embodiment of this disclosure. In the second embodiment, a pair of second flanges 532a, 532b of the impact-absorbing member 530 are joined to the inner member 522 of the side beam. On the other hand, in Figure 21 In the 10th variation of the second embodiment shown, the first top plate portion 531e is joined to the inner member 522 of the side beam by the joining method described above. That is, in the 10th variation of the second embodiment, the impact absorbing member 530 is configured in a shape symmetrical to the impact absorbing member 530 of the embodiment in the width direction X. Moreover, a pair of second flanges 532a and 532b of the second cap member 532 are joined to the reinforcing plate 580 by the joining method described above. The reinforcing plate 580 is formed, for example, of the same material as the first cap member 531 or the second cap member 532, and the second flanges 532a and 532b are joined to each other.

[0357] In the 10th variation of the second embodiment, the second cap member 532 is disposed adjacent to the outer member 521 of the side beam, and the first cap member 531 is disposed at a position biased towards the inner member 522 of the side beam between the outer member 521 and the inner member 522 of the side beam.

[0358] In this way, by joining the first cap member 531 of the impact absorbing member 530 to the inner member 522 of the side beam, the absorption efficiency of impact energy during a side collision can also be improved.

[0359] In addition, by arranging the second cap member 532 adjacent to the outer member 521 of the side beam and positioning the first cap member 531 at a position biased towards the inner member 522 of the side beam, the absorption efficiency of impact energy during a side collision can also be improved.

[0360] [Eleventh variation of the second embodiment]

[0361] Figure 22This is a schematic cross-sectional view showing the main part of the 11th modification of the second embodiment of this disclosure. In this embodiment, an example of a structure in which the impact-absorbing member 530 is disposed within the side beam 515 is described. However, this is not always the case. For example, the impact-absorbing member 530 may also be disposed to the side in the width direction X of the side beam 515.

[0362] In this modified example, the impact-absorbing member 530 is positioned in the width direction X, closer to the vehicle interior than the side beam 515. The impact-absorbing member 530 can be joined to the side wall 600b of the battery housing 600 using the aforementioned joining method, or the first top plate portion 531e can be joined to the side wall 723 of the side beam inner member 522 using the same joining method. In the impact-absorbing member 530, at least one of the first top plate portion 531e and the second flanges 532a and 532b can be joined to the corresponding battery housing 600 and side beam inner member 522. Thus, when the impact-absorbing member 530 is positioned laterally between the side beam 515 and the battery housing 600, impact energy can be absorbed by the collapse of the impact-absorbing member 530 during a side collision. In this modified example, the width-direction end 600a of the battery housing 600 is disposed at the upper part of the battery housing 600, but it may also be disposed at the lower part of the battery housing 600. Furthermore, this modified example is described with the shock-absorbing member 530 disposed between the side beam 515 and the battery housing 600 as an example, but this is not always the case. For example, the shock-absorbing member 530 may also be disposed near the side beam 515, such as below it.

[0363] In this variation, the same structure as the impact-absorbing member 530 in the second embodiment is described as an example, but the impact-absorbing member 530 described in each variation can also be used instead. In this case, the second flanges 532a, 532b and the first top plate portion 531e of the impact-absorbing member 530 are joined to the side beam 515, the battery casing 600 or the components surrounding the impact-absorbing member 530.

[0364] Alternatively, it could be a variation, such as the 11th variation used to illustrate the second embodiment. Figure 23 As shown, the impact absorbing component 530 is separated from the side beam 515.

[0365] [Twelfth variation of the second embodiment]

[0366] Figure 24This is a schematic cross-sectional view showing the main parts of the 12th variation of the second embodiment of this disclosure. In the second embodiment and each of the above-described variations, the structure in which the battery housing 600 is configured to contact the floor panel 518 has been described as an example. However, this is not always the case. For example, the battery housing 600 may also be configured in a position separate from the floor panel 518.

[0367] [13th variation of the second embodiment]

[0368] In the second embodiment, an example was described where the tensile strength TS1 (Vickers hardness HV1) of the first cap member 531 is lower than the tensile strength TS2 (Vickers hardness HV2) of the second cap member 532. However, this is not always the case. The tensile strength TS1 (Vickers hardness HV1) of the first cap member 531 may be higher than the tensile strength TS2 (Vickers hardness HV1) of the second cap member 532 (TS1 > TS2). That is, the strength on the side of the outer member 521 of the impact-absorbing member 530 may be higher than the strength on the side of the inner member 522. In this case, a structure obtained by swapping the tensile strength TS1 of the first cap member 531 and the tensile strength TS2 of the second cap member 532 in the embodiment can be illustrated.

[0369] With this structure, the peak value of the impact load acting on the first cap member 531 can be further increased during a side collision, and the first cap member 531 can absorb more impact energy.

[0370] Alternatively, a structure can be illustrated by swapping the plate thickness t2 of the second cap member 532 and the plate thickness t1 of the first cap member 531 in the second embodiment (t1 > t2). With such a structure, the peak value of the impact load acting on the first cap member 531 can be further increased during a side impact, and more impact energy can be absorbed by the first cap member 531.

[0371] [14th variation of the second embodiment]

[0372] Figure 25 This is a schematic cross-sectional view showing the main part of the 14th variation of the second embodiment of the present disclosure. Figure 26This is a schematic perspective view showing the main parts of the 14th variation of the second embodiment of this disclosure. In the second embodiment and various variations, the first flanges 531a and 531b of the first cap member 531 are joined to the second top plate portion 532e of the second cap member 532, but not to the second ridge portions 532h and 532i, or the longitudinal wall portions 532c and 532d on the top side. In contrast, as shown in the 14th variation of this second embodiment, the first flanges 531a and 531b of the first cap member 531 may also be joined to the second ridge portions 532h and 532i, or the longitudinal wall portions 532c and 532d on the top side of the second cap member 532. In this case, the first flanges 531a and 531b are also joined to the second top plate portion 532e.

[0373] In this 14th modification, reinforcing ribs 570 (571, 572) may also be formed in the impact-absorbing member 530. In this 14th modification, the reinforcing ribs 571 and 572 are provided to improve the stiffness (at least one of bending stiffness and torsional stiffness) of the first cap member 531. The reinforcing rib 571 is formed in one longitudinal wall portion 531c of the first cap member 531, and the reinforcing rib 572 is formed in the other longitudinal wall portion 531d of the first cap member 531. Preferably, the positions of the pair of reinforcing ribs 571 and 572 in the front-rear direction Y are aligned. The reinforcing ribs 571 and 572 are formed by recessing the corresponding longitudinal wall portions 531c and 531d of the first cap member 531. The reinforcing ribs 571 and 572 may also be formed by setting the corresponding longitudinal wall portions 531c and 531d of the first cap member 531 to a shape that protrudes in the height direction Z. The dimensions of the reinforcing ribs 571 and 572 in the width direction X, front-to-back direction Y, and height direction Z are not particularly limited, as long as they can improve at least one of the bending stiffness and torsional stiffness of the first cap member 531.

[0374] [Other variations of the second embodiment]

[0375] In the various embodiments and modifications described above, a reinforcing member may also be sandwiched between the impact-absorbing member 530 and the floor beams 516 and 517. This reinforcing member is configured to suppress bending of the floor beams 516 and 517 due to the impact load transmitted from the impact-absorbing member 530 to the floor beams 516 and 517 via the side beam 515.

[0376] In addition, the impact-absorbing member 530 in the above-described embodiments and variations can also be formed of aluminum alloy or composite materials such as CFRP (Carbon Fiber Reinforced Plastics).

[0377] Furthermore, while the above-described embodiments and modifications primarily focus on monocoque vehicle bodies, this approach is not always applicable. For instance, this disclosure can also be applied to vehicle bodies with trapezoidal frame structures.

[0378] Industrial availability

[0379] This disclosure can be widely used as a side beam structure and the lower structure of automobiles.

[0380] Explanation of reference numerals in the attached figures

[0381] 14. Side beam structure; 15. Side beam; 16, 17. Floor beam; 21. External side beam component; 22. Internal side beam component; 23. Closed cross-section space; 30. Impact absorbing component; 31. First cap component; 32. Second cap component; 40. Cap-shaped part; 41. First top plate part; 42. Second top plate part; 45, 46. A pair of longitudinal wall parts; 45a, 46a. A pair of first parts; 45b, 46b. A pair of second parts; 47, 48. A pair of flanges; 61. First closed cross-section part; 62. Second closed cross-section part; 70. Reinforcing rib; 100. Battery casing; 101. Battery; 514. Side beam structure; 515. Side beam; 516, 517. Floor beam; 530. Impact absorbing component; 521. External component of side beam; 522. Internal component of side beam; 523. Closed cross-section space; 531. First cap component; 532. Second cap component; 540. Cap-shaped part; 531e. First top plate part; 532e. Second top plate part; 545, 546. A pair of longitudinal wall parts; 531c, 531d. Longitudinal wall parts (a pair of first parts); 532c, 532d. Longitudinal wall parts (a pair of second parts); 532a, 532b. A pair of flanges; 561. First closed cross-section part; 562. Second closed cross-section part; 570. Reinforcing rib; 600. Battery casing; 601. Battery; X. Width direction; Y. Front-rear direction; Z. Height direction.

Claims

1. A side beam structure, wherein, The side beam structure includes: A side beam, comprising an outer side beam member and an inner side beam member disposed inside the outer side beam member in the vehicle width direction, extending in the vehicle longitudinal direction and forming a closed cross-sectional space in a section orthogonal to the vehicle longitudinal direction; and Impact-absorbing components, which are formed by multiple components. The impact-absorbing member includes, in the cross-section: a hat-shaped portion having a first top plate portion extending in the vehicle height direction and a pair of longitudinal wall portions extending from both ends of the first top plate portion in the vehicle height direction along the vehicle width direction; and a second top plate portion disposed above the ground with the first top plate portion in the vehicle width direction and connecting the pair of longitudinal wall portions to each other. The second top plate portion divides the inner space of the hat-shaped portion in the vehicle width direction, thereby forming a first closed section portion including the first top plate portion and a second closed section portion adjacent to the first closed section portion in the vehicle width direction. The impact absorbing member is separated from the outer member of the side beam, or the impact absorbing member is in contact with the outer member of the side beam without being engaged with it.

2. The side beam structure according to claim 1, wherein, The impact-absorbing component is formed by combining a first cap component and a second cap component. The top plate portion of the first cap member forms the first top plate portion, and the top plate portion of the second cap member forms the second top plate portion. A pair of first portions, which are a pair of longitudinal wall portions of the first cap member, and a pair of second portions, which are a pair of longitudinal wall portions of the second cap member, cooperate to form a pair of longitudinal wall portions.

3. The side beam structure according to claim 2, wherein, The Vickers hardness of the first cap component is lower than that of the second cap component.

4. The side beam structure according to claim 2, wherein, The Vickers hardness of the first cap component is higher than that of the second cap component.

5. The side beam structure according to claim 2, wherein, The thickness of the first cap component is smaller than the thickness of the second cap component.

6. The side beam structure according to claim 2, wherein, The thickness of the first cap component is greater than the thickness of the second cap component.

7. The side beam structure according to claim 2, wherein, For the Vickers hardness HV1 and plate thickness t1 at the first cap component, and the Vickers hardness HV2 and plate thickness t2 at the second cap component, 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, HV1×t1<HV2×t2.

8. The side beam structure according to claim 2, wherein, The impact-absorbing member includes a cap member forming the cap-shaped portion and a top plate member forming the second top plate portion.

9. The side beam structure according to claim 8, wherein, For the Vickers hardness HV2 and plate thickness t2 at the cap component, and the Vickers hardness HV1 and plate thickness t1 at the top plate component... 180≤HV1, HV2≤780, 0.8mm≤t1, t2≤2.3mm, HV1×t1<HV2×t2.

10. The side beam structure according to claim 1, wherein, The second top plate portion of the impact-absorbing member has a shape that protrudes towards the first top plate portion in the cross section.

11. The side beam structure according to claim 1, wherein, The impact-absorbing component is made of steel plate.

12. The side beam structure according to claim 1, wherein, The cap-shaped portion includes a pair of flanges extending from the pair of longitudinal wall portions. A pair of the flanges are engaged with the inner member of the side beam.

13. The side beam structure according to claim 1, wherein, The impact-absorbing member is provided with reinforcing ribs.

14. The side beam structure according to claim 1, wherein, The impact-absorbing member is supported on the side beam within the closed cross-sectional space, or the impact-absorbing member is disposed to the side of the side beam in the vehicle width direction.

15. The side beam structure according to claim 2, wherein, The first cap member includes a pair of first flanges, a pair of first longitudinal wall portions extending from the pair of first flanges, and a first top plate portion connecting the pair of first longitudinal wall portions. The second cap member includes a pair of second flanges, a pair of second longitudinal wall portions extending from the pair of second flanges, and a second top plate portion connecting the pair of second longitudinal wall portions and engaging with the pair of first flanges.

16. The side beam structure according to claim 2, wherein, At least one of the described cap components further includes a reinforcing member.

17. The side beam structure according to claim 2, wherein, The impact-absorbing member further comprises an nth cap member formed in a cap shape in the cross-section, where n is a natural number greater than or equal to 3. The nth cap member includes a pair of nth flanges, a pair of nth longitudinal wall portions extending from the pair of nth flanges, and an nth top plate portion connecting the pair of nth longitudinal wall portions. Each of the cap components is arranged along the width direction of the vehicle, and in adjacent cap components, the top plate portion engages with a pair of flanges.

18. The side beam structure according to claim 1, wherein, The impact-absorbing component is made of steel plate.

19. A lower structure for a car, wherein, The lower structure of the vehicle includes the side beam structure as described in any one of claims 1 to 18. The side beams are provided separately in a pair in the vehicle width direction. The lower structure of the vehicle also includes a plurality of crossbeams disposed between the pair of said side beams and extending in the vehicle width direction. The impact-absorbing component is disposed inside each of the pair of side beams or on the inside of the vehicle width direction.

20. The lower structure of the automobile according to claim 19, wherein, The vehicle's lower structure also includes a battery housing located below the crossbeam and housing the battery.

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