Energy absorbing material

Abstract

The energy absorbing member (10, 10A) comprises a member body (11) and an inward-facing flange (12). The member body (11) includes a first plate portion (111), a second plate portion (112), and a first ridge portion (114). The first ridge portion (114) connects the first plate portion (111) and the second plate portion (112). The inward-facing flange (12) is provided on the edge of the member body (11) in the direction of extension of the first ridge portion (114). The inward-facing flange (12) is continuous with at least the first ridge portion (114). The inward-facing flange (12) protrudes inward from the member body (11) when viewed along the extension direction. When Lp is the protruding length of the inward-facing flange (12) at the plate portion (111,112) and Lr is the protruding length of the inward-facing flange (12) at the first ridge portion (114), the following conditions are met: Lp ≥ 0 mm, Lr > 0 mm, and Lr ≥ Lp.

Description

【Technical Field】 , , , , , , 【0005】 , , , 【0001】 The present disclosure relates to an energy absorption member for a vehicle. 【Background Art】 【0002】 Various members are used in vehicles such as automobiles. The members for vehicles are, for example, press-molded products. Patent Document 1 discloses press-molded products suitable for members such as bumper reinforcements, rockers (side sills), belt lines, cross members, and the like. 【0003】 The press-molded product of Patent Document 1 includes two first surface portions and second surface portions each connected to each of the first surface portions via ridge line portions. This press-molded product has an inward continuous flange. The inward continuous flange includes a first flange, a second flange, and a ridge line portion flange. The first flange is provided on each of the first surface portions at an end in the longitudinal direction of the press-molded product. The second flange is provided on the second surface portion at an end in the longitudinal direction of the press-molded product. The ridge line portion flange is provided on the ridge line portion at an end in the longitudinal direction of the press-molded product. The width of the ridge line portion flange is smaller than the width of each of the first flange and the second flange. Patent Document 1 describes that since the width of the ridge line portion flange is smaller than the width of each of the first flange and the second flange, the excess elongation at the tip of the ridge line portion flange is reduced and the occurrence of wrinkles is reduced. 【Prior Art Documents】 【Patent Documents】 【0004】 【Patent Document 1】<00,00021>Japanese Patent No. 6128226 【Summary of the Invention】<00000,23> 【Problems to be Solved by the Invention】 <00000,27> Vehicles may be equipped with energy-absorbing components. These components are designed to absorb collision energy during a vehicle collision. Energy-absorbing components are required to exhibit high energy absorption performance. 【0006】 This disclosure aims to improve the energy absorption performance of energy absorption components for vehicles. [Means for solving the problem] 【0007】 The energy absorbing member for a vehicle according to this disclosure comprises a member body and an inward-facing flange. The member body includes a first plate portion, a second plate portion, and a first ridge portion. The first ridge portion connects the first plate portion and the second plate portion. The inward-facing flange is provided on the edge of the member body in the extending direction of the first ridge portion. The inward-facing flange is continuous with at least the first ridge portion. The inward-facing flange protrudes inward from the member body when viewed along the extending direction. When the protrusion length of the inward-facing flange at the first plate portion and the second plate portion is Lp, and the protrusion length of the inward-facing flange at the first ridge portion is Lr, the following conditions are met: Lp ≥ 0 mm, Lr > 0 mm, and Lr ≥ Lp. [Effects of the Invention] 【0008】 According to this disclosure, the energy absorption performance of energy absorption members for vehicles can be improved. [Brief explanation of the drawing] 【0009】 [Figure 1] Figure 1 is a schematic diagram showing the usage state of the energy absorbing member according to the first embodiment. [Figure 2] Figure 2 is a perspective view of the energy absorbing member according to the first embodiment. [Figure 3] Figure 3 is a cross-sectional view of the energy absorbing member shown in Figure 2, taken along line III-III. [Figure 4] Figure 4 is a cross-sectional view taken along line IV-IV of the energy absorbing member shown in Figure 2. [Figure 5]Figure 5 is a VV cross-sectional view of the energy absorbing member shown in Figure 2. [Figure 6] Figure 6 is a cross-sectional view of the energy absorbing member shown in Figure 2, taken along the line VI-VI. [Figure 7] Figure 7 is a perspective view of the energy absorbing member according to the second embodiment. [Figure 8] Figure 8 is a cross-sectional view taken along line VIII-VIII of the energy absorbing member shown in Figure 7. [Figure 9] Figure 9 is a cross-sectional view taken along line IX-IX of the energy absorbing member shown in Figure 7. [Figure 10] Figure 10 is a cross-sectional view of the energy absorbing member shown in Figure 7. [Figure 11A] Figure 11A is a perspective view of an energy absorbing member according to a modified example of the first embodiment. [Figure 11B] Figure 11B is a perspective view of an energy absorbing member according to a modified example of the first embodiment. [Figure 12] Figure 12 is a perspective view of an energy absorbing member according to a modified example of each embodiment. [Figure 13] Figure 13 is a perspective view of an energy absorbing member according to another modified example of the first embodiment. [Figure 14] Figure 14 is a perspective view of an energy absorbing member according to yet another modification of the first embodiment. [Figure 15] Figure 15 is a perspective view of an energy absorbing member according to yet another modification of the first embodiment. [Figure 16] Figure 16 is a cross-sectional view of an energy absorbing member according to another modified example of each embodiment. [Figure 17] Figure 17 is a graph showing the energy absorption per unit weight for Example 1 and Comparative Example 1. [Figure 18] Figure 18 is a graph showing the energy absorption amounts for Example 2 and Comparative Example 2. [Figure 19] Figure 19 is a graph showing the energy absorption amounts for Examples 3-1 to 3-2 and Comparative Examples 3-1 to 3-2. [Figure 20]FIG. 20 is a graph showing the relationship between R / t and the energy absorption amount. BEST MODE FOR CARRYING OUT THE INVENTION 【0010】 The energy absorption member for a vehicle according to the embodiment includes a member main body and an inward flange. The member main body includes a first plate portion, a second plate portion, and a first ridge portion. The first ridge portion connects the first plate portion and the second plate portion. The inward flange is provided at the edge of the member main body in the extending direction of the first ridge portion. The inward flange is at least continuous with the first ridge portion. The inward flange protrudes inward from the member main body when viewed along the extending direction. When the protruding length of the inward flange at the first plate portion and the second plate portion is Lp, and the protruding length of the inward flange at the first ridge portion is Lr, Lp≧0 mm, Lr>0 mm, and Lr≧Lp are satisfied (first configuration). 【0011】 In the energy absorption member according to the first configuration, an inward flange is provided at the edge of the member main body. The inward flange is provided at least continuously with the first ridge portion that connects the first plate portion and the second plate portion of the member main body. The protruding length Lr of the inward flange at the first ridge portion is not less than the protruding length Lp of the inward flange at the first plate portion and the second plate portion. Since the rigidity of the energy absorption member is increased by this inward flange, when a collision load is input in the extending direction of the first ridge portion to the energy absorption member, cross-sectional deformation of the energy absorption member is less likely to occur. Therefore, the collision load can be supported by the first ridge portion, and the energy absorption amount of the energy absorption member increases. That is, the energy absorption performance of the energy absorption member can be improved. 【0012】 In the energy absorption member according to the first configuration, the inward flange may include a curved portion. The curved portion is adjacent to the edge of the member main body. The curved portion has a curved shape convex outward of the energy absorption member in a cross-sectional view of the inward flange. When the radius of curvature of the curved portion is R and the plate thickness of the member main body is t, R / t≦15.0 may be satisfied (second configuration). 【0013】 In the second configuration, the radius of curvature R of the curved portion of the inward-facing flange is small relative to the plate thickness t of the member body. More specifically, the radius of curvature R of the curved portion and the plate thickness t of the member body satisfy R / t ≤ 15.0. This makes it easier for the first ridge portion to support the collision load, and the amount of energy absorbed by the energy absorbing member can be increased. 【0014】 In the energy absorbing member according to the first or second configuration, the inward-facing flange may be continuous with at least one of the first plate portion and the second plate portion and the first ridge portion (third configuration). 【0015】 In the third configuration, the inward-facing flange is continuous not only with the first ridge of the member body, but also with one or both of the first and second plate portions. This makes it less likely for the cross-sectional deformation of the energy-absorbing member to occur when a collision load is applied, and increases the amount of energy absorbed by the energy-absorbing member. 【0016】 In an energy absorbing member relating to any of the first to third configurations, the member body may further include a third plate portion and a second ridge portion. The third plate portion is positioned on the opposite side of the second plate portion from the first plate portion. The second ridge portion connects the first plate portion and the third plate portion (fourth configuration). 【0017】 In the energy absorbing member according to the fourth configuration, the member body may include a plurality of convex portions. Each of the plurality of convex portions includes a first plate portion, a second plate portion, a third plate portion, a first ridge portion, and a second ridge portion. The plurality of convex portions may be arranged and connected such that the second plate portion on one of two adjacent convex portions faces the third plate portion on the other of the two convex portions (fifth configuration). 【0018】 In the fifth configuration, the member body includes multiple convex portions, and each of the convex portions is provided with an inward-facing flange that is continuous with at least the first ridge portion. This makes it less likely for the cross-sectional deformation of the energy absorbing member to occur when a collision load is applied, and increases the amount of energy absorbed by the energy absorbing member. 【0019】 An energy absorbing member relating to any of the first to fifth configurations may have a Vickers hardness of 300 HV or more (sixth configuration). 【0020】 In the sixth configuration, the Vickers hardness of the energy-absorbing member is 300 HV or higher. This further improves the energy absorption performance of the energy-absorbing member. 【0021】 Embodiments of this disclosure will be described below with reference to the drawings. In these drawings, the same or equivalent components are denoted by the same reference numerals, and the same description will not be repeated. 【0022】 <First Embodiment> Figure 1 is a schematic diagram showing the usage state of the energy absorbing member 10 according to this embodiment. The energy absorbing member 10 is used in a vehicle. Figure 1 shows an example in which the energy absorbing member 10 is used in a vehicle battery pack. The energy absorbing member 10 is attached, for example, to the battery pack case 20. However, the energy absorbing member 10 may be used in vehicle parts other than the battery pack. For example, the energy absorbing member 10 can be placed within a vehicle frame member such as a side sill. 【0023】 Referring to Figure 1, the case 20 includes a peripheral wall 21, a bottom plate 22, and a flange 23. The case 20 has, for example, a rectangular shape when viewed from above. In this case, the peripheral wall 21 may include side walls 211, 212, 221, and 222. The side walls 211 and 212 face each other in the width direction of the case 20 and extend in the longitudinal direction of the case 20. Side wall 221 connects side walls 211 and 212 on one side in the longitudinal direction of the case 20. Side wall 222 connects side walls 211 and 212 on the other side in the longitudinal direction of the case 20. The side walls 221 and 222 face each other in the longitudinal direction of the case 20. The width direction and longitudinal direction of the case 20 may correspond to the vehicle width direction and vehicle length direction of the vehicle on which the case 20 is mounted, respectively. 【0024】 The base plate 22 is positioned below the peripheral wall 21 and is connected to the peripheral wall 21 around its entire circumference. The flange 23 is connected to the peripheral wall 21 on the opposite side of the base plate 22. The flange 23 is connected around the entire circumference of the peripheral wall 21 and protrudes outward from the peripheral wall 21. 【0025】 The energy absorbing member 10 is attached directly or indirectly to the peripheral wall 21 of the case 20. For example, at least one energy absorbing member 10 is attached to each of the side walls 211 and 212 that are opposite in the vehicle width direction. However, the energy absorbing member 10 may be attached to one or both of the side walls 221 and 222 that are opposite in the vehicle length direction. That is, the energy absorbing member 10 may be attached to the front side wall 221, or to the rear side wall 222. 【0026】 In the example shown in Figure 1, the energy absorbing member 10 is located on the outside of the case 20. However, the energy absorbing member 10 may also be located inside the case 20. One or more energy absorbing members 10 are attached to at least one of the side walls 211, 212, 221, and 222, either from outside or inside the case 20. 【0027】 Figure 2 is a perspective view of the energy absorbing member 10. Referring to Figure 2, the energy absorbing member 10 comprises a member body 11 and at least one inward-facing flange 12. 【0028】 In this embodiment, the member body 11 includes a plurality of convex portions 11C. The member body 11 may include 2 to 15 convex portions 11C. The member body 11 may also include 10 or fewer convex portions 11C. Each convex portion 11C includes plate portions 111, 112, 113 and edge portions 114, 115. 【0029】 The ridge portion 114 is continuous with the plate portion 111. The plate portion 112 is continuous with the ridge portion 114. That is, the ridge portion 114 connects the plate portion 111 and the plate portion 112. The ridge portion 114 extends between the plate portions 111 and 112. In this embodiment, the ridge portion 114 extends in a direction corresponding to the vehicle width direction of the vehicle in which the energy absorbing member 10 is used. 【0030】 The plate portion 113 and the ridge portion 115 are positioned on the opposite side of the plate portion 111 from the plate portion 112 and the ridge portion 114. The ridge portion 115 is continuous with the plate portion 111. The plate portion 113 is continuous with the ridge portion 115. That is, the ridge portion 115 connects the plate portion 111 and the plate portion 113. The ridge portion 115 extends between the plate portions 111 and 113. In this embodiment, the ridge portion 115 extends in a direction corresponding to the vehicle width direction of the vehicle in which the energy absorbing member 10 is used. 【0031】 Multiple convex portions 11C are arranged and connected along a direction intersecting the extending direction of the ridge portions 114 and 115. More specifically, multiple convex portions 11C are arranged such that the plate portion 112 of one of two adjacent convex portions 11C faces the plate portion 113 of the other convex portion 11C. In this embodiment, the direction of arrangement of the convex portions 11C is the longitudinal direction of the energy absorbing member 10. The longitudinal direction of the energy absorbing member 10 may correspond to the vehicle length direction of the vehicle in which the energy absorbing member 10 is used. 【0032】 Adjacent convex portions 11C are connected by a bottom portion 116. The bottom portion 116 connects the plate portion 112 of one convex portion 11C to the plate portion 113 of the other convex portion 11C on the opposite side of the plate portion 111. When the plate portion 111 side of each convex portion 11C is considered the upper side and the opposite side the lower side, the bottom portion 116 connects the lower ends of adjacent convex portions 11C. As a result, the member body 11 can have a wave shape when viewed along the extending direction of the ridge portions 114 and 115. 【0033】 In this embodiment, flanges 117 are provided on the convex portions 11C located at both ends in the longitudinal direction of the energy absorbing member 10. At these convex portions 11C, the flanges 117 are connected to the plate portion 112, 113 that does not have a bottom portion 116, and protrude from the plate portion in the longitudinal direction of the energy absorbing member 10. 【0034】 Figure 3 is a cross-sectional view of the energy absorbing member 10 shown in Figure 2, taken along line III-III. In Figure 2, the cross-section (longitudinal section) of the member body 11 perpendicular to the extension direction of the ridges 114 and 115 is shown. 【0035】 Referring to Figure 3, the plate portion 111 extends in the longitudinal direction of the energy absorbing member 10 in a longitudinal cross-sectional view of the member body 11. The plate portion 111 may be parallel or non-parallel to the longitudinal direction of the energy absorbing member 10. In this embodiment, the plate portion 111 is substantially straight in a longitudinal cross-sectional view of the member body 11. 【0036】 Plate portion 111 is connected to plate portion 112 via ridge portion 114. Plate portion 111 is also connected to plate portion 113 via ridge portion 115. Ridge portions 114 and 115 are corner portions between plate portions 112, 113 and plate portion 111, respectively. Ridge portions 114 and 115 have an outwardly convex curved shape in a longitudinal cross-sectional view of the member body 11. Ridge portions 114 and 115 can smoothly connect plate portions 112, 113 and plate portion 111. On the other hand, plate portions 112 and 113, like plate portion 111, can have a substantially straight shape in a longitudinal cross-sectional view of the member body 11. However, plate portions 111, 112, and 113 may have concave or convex beads or the like in part. 【0037】 The plate portions 112 and 113 may be parallel or non-parallel to each other in a longitudinal cross-sectional view of the member body 11. In this embodiment, the plate portions 112 and 113 are inclined with respect to a direction perpendicular to the plate portion 111 such that they move further apart from each other as they move away from the plate portion 111. The plate portions 112 and 113 are connected to a bottom portion 116 or a flange 117. 【0038】 The bottom portion 116 may include a bottom body 116a and two ridge portions 116b. The bottom body 116a extends in the longitudinal direction of the energy absorbing member 10 in a longitudinal cross-sectional view of the member body 11. The bottom body 116a may be parallel or non-parallel to the longitudinal direction of the energy absorbing member 10. In this embodiment, the bottom body 116a is substantially straight in a longitudinal cross-sectional view of the member body 11. However, the bottom body 116a may have concave or convex beads or the like in part thereof. The bottom body 116a is connected via the ridge portions 116b to the plate portion 112 of one of the adjacent convex portions 11C and the plate portion 113 of the other convex portion 11C. The ridge portions 116b are corner portions between the plate portions 112, 113 and the bottom body 116a. The ridge portion 116b has a curved shape that is convex on the opposite side from the ridge portion 114 or 115 when viewed in a longitudinal section of the member body 11. The ridge portion 116b can smoothly connect the plate portions 112, 113 and the bottom body 116a. 【0039】 The flange 117 may include a flange body 117a and a ridge portion 117b. The flange body 117a extends in the longitudinal direction of the energy absorbing member 10 in a longitudinal cross-sectional view of the member body 11. The flange body 117a may be parallel or non-parallel to the longitudinal direction of the energy absorbing member 10. In this embodiment, the flange body 117a is substantially straight in a longitudinal cross-sectional view of the member body 11. However, the flange body 117a may have concave or convex beads or the like in part thereof. The flange body 117a is connected via the ridge portion 117b to the plate portion 112 or 113 of the convex portion 11C located at both ends in the longitudinal direction of the energy absorbing member 10. The ridge portion 117b is the corner portion between the plate portion 112 or 113 and the flange body 117a. The ridge portion 117b has a curved shape that is convex on the opposite side from the ridge portion 114 or 115 when viewed in a longitudinal section of the member body 11. The ridge portion 117b can smoothly connect the plate portion 112 or 113 and the flange body 117a. 【0040】 The main body of the component 11 has a plate thickness t. The plate thickness t is the plate thickness measured at the flat portion of the plate portion 111. Although not particularly limited, the plate thickness t is, for example, 0.1 mm or more, and preferably 0.6 mm or more. The plate thickness t is, for example, 6.0 mm or less, and preferably 2.6 mm or less. 【0041】 Returning to Figure 2, the inward-facing flange 12 is provided integrally with the member body 11 in the energy-absorbing member 10. The inward-facing flange 12 is provided on the edge of the member body 11 in the direction of extension of the ridge portions 114 and 115. The inward-facing flange 12 protrudes inward from the member body 11 when viewed along the direction of extension of the ridge portions 114 and 115. The inward-facing flange 12 is provided on at least one of the convex portions 11C. In this embodiment, the inward-facing flange 12 is provided on each of the convex portions 11C. 【0042】 In each of the convex portions 11C, the inward-facing flange 12 is continuous with at least the ridge portion 114 of the member body 11. If the member body 11 has two ridge portions 114 and 115, the inward-facing flange 12 may be continuous with each of the ridge portions 114 and 115. The inward-facing flange 12 is continuous with the entirety of the ridge portions 114 and 115. In this embodiment, in addition to the ridge portions 114 and 115, the inward-facing flange 12 is also continuous with the plate portions 111, 112 and 113. That is, the inward-facing flange 12 is provided on the member body 11 across the plate portion 112, the ridge portion 114, the plate portion 111, the ridge portion 115, and the plate portion 113. 【0043】 Figure 4 is a cross-sectional view of the energy absorbing member 10 shown in Figure 2, taken along line IV-IV. Figure 5 is a cross-sectional view of the energy absorbing member 10 shown in Figure 2, taken along line VV. Figure 6 is a cross-sectional view of the energy absorbing member 10 shown in Figure 2, taken along line VI-VI. Figure 4 shows the cross-section (transverse plane) of the member body 11 and the inward flange 12 when cut along the thickness direction and extension direction of the ridge portion 114 at the position of the ridge portion 114. Figure 5 shows the cross-section (transverse plane) of the member body 11 and the inward flange 12 when cut along the thickness direction of the plate portion 111 and the extension direction of the ridge portion 114 at the position of the plate portion 111. Figure 6 shows the cross-section (transverse plane) of the member body 11 and the inward flange 12 when cut along the thickness direction of the plate portion 112 and the extension direction of the ridge portion 114 at the position of the plate portion 112. 【0044】 Referring to Figure 4, the inward-facing flange 12 may include a curved portion 121 and a straight portion 122. In a cross-sectional view of the inward-facing flange 12, the curved portion 121 has a curved shape that is convex outward from the energy-absorbing member 10. The curved portion 121 is adjacent to the edge of the member body 11 in the direction of extension of the ridge portion 114. The curved portion 121 is provided continuously with the ridge portion 114. 【0045】 The curved portion 121 has a radius of curvature R. The radius of curvature R is the radius of curvature of the inner surface of the curved portion 121. The radius of curvature R may be, for example, the radius of the approximate circle formed from both ends (ends of R) and their midpoints on the inner surface of the curved portion 121 in the cross-section of the inward flange 12 shown in Figure 4. The radius of curvature R is, for example, 0.1 mm or more, preferably 0.5 mm or more. The radius of curvature R is, for example, 90.0 mm or less, preferably 35.0 mm or less. The radius of curvature R of the curved portion 121 and the plate thickness t of the member body 11 (Figure 3) preferably satisfy R / t ≤ 15.0. The radius of curvature R and plate thickness t more preferably satisfy R / t ≤ 10.0. The radius of curvature R and plate thickness t may satisfy R / t ≥ 0.5. 【0046】 In a cross-sectional view of the inward-facing flange 12, the straight portion 122 is substantially straight. The straight portion 122 is provided continuously with the curved portion 121. The straight portion 122 is connected to the edge of the member body 11 in the extending direction of the ridge portion 114 via the curved portion 121. The straight portion 122 is connected to the ridge portion 114 by the curved portion 121. The end of the straight portion 122 opposite to the curved portion 121 is a free end. 【0047】 As shown in Figure 4, the inward-facing flange 12 has a protruding length Lr at the ridge portion 114. More specifically, the cross-section of the member body 11 and the inward-facing flange 12 at the center of the ridge portion 114 in the circumferential direction of the member body 11 is used as the measurement cross-section, and the length of the inward-facing flange 12 measured along the outer surface at this measurement cross-section is the protruding length Lr. The circumferential direction of the member body 11 refers to the direction along the surface of the member body 11 in the longitudinal cross-section of the member body 11 (Figure 3). In this embodiment, the protruding length Lr is the length from the end of the curved portion 121 on the ridge portion 114 side (end of R) to the free end of the straight portion 122. 【0048】 Referring to Figure 5, in this embodiment, the inward-facing flange 12 is continuous with the plate portion 111. More specifically, the curved portion 121 of the inward-facing flange 12 is continuous with the plate portion 111 in addition to the ridge portion 114 (Figure 4). The curved portion 121 is continuous with the entire plate portion 111. However, the curved portion 121 may be continuous with only a part of the plate portion 111. The straight portion 122 is also connected to the plate portion 111 by the curved portion 121. 【0049】 Referring to Figure 6, in this embodiment, the inward-facing flange 12 is continuous with the plate portion 112. More specifically, the curved portion 121 of the inward-facing flange 12 is continuous with the plate portion 112 in addition to the ridge portion 114 (Figure 4) and the plate portion 111 (Figure 5). The curved portion 121 is continuous with the entire or substantially entire plate portion 112. However, the curved portion 121 may be continuous with only a part of the plate portion 112. The straight portion 122 is also connected to the plate portion 112 by the curved portion 121. 【0050】 As shown in Figures 5 and 6, the inward-facing flange 12 has a protruding length Lp in the plate portions 111 and 112. More specifically, the cross-section of the member body 11 and the inward-facing flange 12 at the center of the plate portion 111 in the circumferential direction of the member body 11 (Figure 5) is used as the measurement cross-section, and the length of the inward-facing flange 12 measured along the outer surface in this measurement cross-section is defined as the protruding length Lp1 in the plate portion 111. Similarly, the cross-section of the member body 11 and the inward-facing flange 12 at the center of the plate portion 112 in the circumferential direction of the member body 11 (Figure 6) is used as the measurement cross-section, and the length of the inward-facing flange 12 measured along the outer surface in this measurement cross-section is defined as the protruding length Lp2 in the plate portion 112. The protruding lengths Lp1 and Lp2 may be equal or different. The maximum value of the protruding lengths Lp1 and Lp2 is the protruding length Lp of the inward-facing flange 12 in the plate portions 111 and 112. In this embodiment, the length from the end of the curved portion 121 on the plate portion 111, 112 side (end of R) to the free end of the straight portion 122 is the protruding length Lp1, Lp2 of the plate portion 111, 112. 【0051】 The protruding length Lr of the inward-facing flange 12 at the ridge portion 114 (Figure 4), and the protruding length Lp of the inward-facing flange 12 at the plate portions 111 and 112 (Figures 5 and 6) satisfy the following conditions (1) to (3). Lp≧0mm (1) Lr>0mm (2) Lr≧Lp (3) 【0052】 The protruding length Lr of the inward-facing flange 12 at the ridge portion 114 should be greater than 0 mm, but may be 1 mm or more. The protruding length Lr is preferably 2 mm or more, and more preferably 4 mm or more. The protruding length Lr may be 50 mm or less. 【0053】 The protruding length Lp of the inward-facing flange 12 on the plate portions 111 and 112 should be 0 mm or more, but is preferably greater than 0 mm. That is, it is preferable that the inward-facing flange 12 is provided continuously on at least one of the plate portions 111 and 112 on both sides of the ridge portion 114, in addition to the ridge portion 114. In this case, the protruding length Lp is, for example, 1 mm or more, preferably 2 mm or more, and more preferably 4 mm or more. The protruding length Lp may also be 50 mm or less. 【0054】 In this embodiment, a ridge portion 115 and a plate portion 113 are provided on the opposite side of the plate portion 111 from the ridge portion 114 and plate portion 112 (Figure 2). As described above, the inward flange 12 is continuous with the ridge portion 115 and plate portion 113. Although not shown, the inward flange 12 can have a protruding length Lr (Figure 4) at the ridge portion 115, similar to the ridge portion 114. It is preferable that the protruding length Lr of the inward flange 12 at the ridge portion 115, along with the protruding length Lp (Figures 5 and 6) of the inward flange 12 at the plate portions 111 and 112, satisfies the above equations (1) to (3). The protruding length of the inward flange 12 at the plate portion 113 can be set, for example, in the same way as the protruding length Lp2 of the inward flange 12 at the plate portion 112. 【0055】 The energy absorbing member 10 according to this embodiment is typically formed from a metal plate. The energy absorbing member 10 may also be formed from a steel plate. The energy absorbing member 10 can be formed by pressing or bending a metal plate (blank). For example, the end of the blank can be bent to form a portion corresponding to the inward flange 12, and then the blank can be pressed or bent to form a member body 11 with the inward flange 12. Alternatively, the blank can be pressed or bent to form the member body 11, and then the end of the member body 11 can be bent to form the inward flange 12. 【0056】 The energy absorbing member 10 can have a Vickers hardness of 300 HV or more. Preferably, the energy absorbing member 10 has a Vickers hardness of 320 HV or more. The Vickers hardness of the energy absorbing member 10 can be obtained by performing a Vickers hardness test in accordance with JIS Z 2244:2024. Specifically, a test piece for the Vickers hardness test is cut out from the flat portion of the member body 11. The test piece can be cut out from, for example, the plate portion 111. Then, using this test piece, a Vickers hardness test is performed on a cross section along the thickness direction in accordance with JIS Z 2244:2024. More specifically, the Vickers hardness is measured at the center or near the center in the thickness direction of the cross section, and at a position 1 / 4 of the thickness away from each of the front and back surfaces, with a test force of 300 gf (2.9 N). The average of the obtained Vickers hardness is the Vickers hardness of the energy absorbing member 10. 【0057】 [effect] In the energy absorbing member 10 according to this embodiment, an inward-facing flange 12 is provided at the edge of the member body 11. The inward-facing flange 12 is provided continuously with at least the ridge portion 114 of the member body 11. The protruding length Lr of the inward-facing flange 12 at the ridge portion 114 is greater than or equal to the length Lp of the inward-facing flange 12 at the plate portion 112, 112. The inward-facing flange 12 configured in this way can increase the rigidity of the energy absorbing member 10. Therefore, when an impact load is applied to the energy absorbing member 10 in the direction of extension of the ridge portion 114, cross-sectional deformation of the energy absorbing member 10 becomes less likely. Consequently, the impact load can be supported by the ridge portion 114, and the amount of energy absorbed by the energy absorbing member 10 increases. In other words, the energy absorption performance of the energy absorbing member 10 can be improved. 【0058】 In the energy absorbing member 10 according to this embodiment, it is preferable that the radius of curvature R of the curved portion 121 of the inward flange 12 satisfies R / t ≤ 15.0 together with the plate thickness t of the member body 11. In other words, it is preferable that the radius of curvature R of the curved portion 121 be set to be somewhat smaller than the plate thickness t of the member body 11. This makes it easier for the impact load to be supported by the ridge portion 114, and the amount of energy absorbed by the energy absorbing member 10 tends to increase. 【0059】 In the energy absorbing member 10 according to this embodiment, the inward-facing flange 12 is continuous not only with the ridge portion 114 of the member body 11, but also with the plate portions 111 and 112. The inward-facing flange 12 is further continuous with the plate portion 113 and the ridge portion 115. Therefore, when an impact load is applied, cross-sectional deformation of the energy absorbing member 10 is less likely to occur, and the amount of energy absorbed by the energy absorbing member 10 can be increased. 【0060】 The energy absorbing member 10 according to this embodiment has a wave shape when viewed from the side. Specifically, the member body 11 includes a plurality of convex portions 11C, and the convex portions 11C are arranged and connected in the longitudinal direction of the energy absorbing member 10. An inward flange 12 is provided on each of the convex portions 11C. Therefore, when a collision load is applied, cross-sectional deformation of the energy absorbing member 10 is less likely to occur, and the amount of energy absorbed by the energy absorbing member 10 can be increased. 【0061】 In this embodiment, the energy absorbing member 10 preferably has a Vickers hardness of 300 HV or more. This makes it possible to further improve the energy absorption performance of the energy absorbing member 10. 【0062】 <Second Embodiment> Figure 7 is a perspective view of the energy absorbing member 10A according to this embodiment. Figure 8 is a cross-sectional view of the energy absorbing member 10A shown in Figure 7, taken along line VIII-VIII. Figure 9 is a cross-sectional view of the energy absorbing member 10A shown in Figure 7, taken along line IX-IX. Figure 10 is a cross-sectional view of the energy absorbing member 10A shown in Figure 7, taken along line XX. Figures 8 to 10 show cross-sections of the energy absorbing member 10A that correspond to the cross-sections shown in Figures 4 to 6 of the energy absorbing member 10 according to the first embodiment. 【0063】 The energy absorbing member 10A according to this embodiment differs from the energy absorbing member 10 according to the first embodiment in the configuration of the inward-facing flange 12. Specifically, in the energy absorbing member 10 according to the first embodiment, the protruding length of the inward-facing flange 12 is substantially constant throughout. On the other hand, in the energy absorbing member 10A according to this embodiment, the protruding length of the inward-facing flange 12 changes along the circumferential direction of the member body 11. As shown in Figure 7, in the energy absorbing member 10A, the protruding length of the inward-facing flange 12 is smaller at the plate portions 111, 112, and 113 compared to the ridge portions 114 and 115. 【0064】 As shown in Figures 8 to 10, in this embodiment, the protruding length Lp of the inward flange 12 at the ridge portion 114 and the protruding length Lp of the inward flange 12 at the plate portions 111 and 112 satisfy the above-described equations (1) to (3), similar to the first embodiment. However, the protruding length Lr is greater than the protruding length Lp. The protruding length Lr may be 1.2 times or more the protruding length Lp. For example, the protruding length Lr is 50.0 times or less the protruding length Lp. By making the protruding length Lp at the plate portions 111 and 112 smaller than the protruding length Lr at the ridge portion 114, the energy absorption member 10A can be made lighter compared to the case where the protruding length Lp is the same as the protruding length Lr, while ensuring the energy absorption performance of the energy absorption member 10A. 【0065】 Although not shown in the illustration, similar to the first embodiment, the inward-facing flange 12 can also have a protruding length Lr (Figure 8) at the ridge portion 115. In this embodiment as well, it is preferable that the protruding length Lr of the inward-facing flange 12 at the ridge portion 115 satisfies the above equations (1) to (3) together with the protruding length Lp of the inward-facing flange 12 at the plate portions 111 and 112 (Figures 9 and 10). The protruding length Lr of the inward-facing flange 12 at the ridge portion 115 may be smaller than the protruding length Lp of the inward-facing flange 12 at the plate portions 111 and 112. The protruding length of the inward-facing flange 12 at the plate portion 113 can be set, for example, in the same way as the protruding length Lp2 of the inward-facing flange 12 at the plate portion 112. 【0066】 While embodiments relating to this disclosure have been described above, this disclosure is not limited to the embodiments described above, and various modifications are possible as long as they do not deviate from its spirit. 【0067】 In the energy absorbing member 10 according to the first embodiment described above, an inward-facing flange 12 is provided at one end edge of the member body 11 in the direction of extension of the ridge portions 114 and 115. However, as shown in Figures 11A and 11B, inward-facing flanges 12 may be provided at both end edges of the member body 11 in the direction of extension of the ridge portions 114 and 115. Similarly, in the energy absorbing member 10A according to the second embodiment, the inward-facing flange 12 may be provided at one end edge of the member body 11 in the direction of extension of the ridge portions 114 and 115, or at both end edges of the member body 11. 【0068】 In the energy absorbing members 10 and 10A according to the first embodiment described above, inward-facing flanges 12 are continuously provided on the plate portions 111, 112, 113 and the ridge portions 114, 115 of the member body 11. However, inward-facing flanges 12 do not necessarily have to be provided on the plate portions 111, 112, and 113. For example, as shown in Figure 12, the inward-facing flanges 12 may be continuous only on the ridge portions 114 and 115. In this case, the protruding length Lp of the inward-facing flanges 12 on the plate portions 111 and 112 is zero. In the example of Figure 12 as well, the inward-facing flanges 12 may be provided on one end edge of the member body 11 in the extending direction of the ridge portions 114 and 115, or on both end edges of the member body 11. 【0069】 In the energy absorbing member 10 according to the first embodiment described above, the member body 11 includes a plurality of convex portions 11C. However, as shown in Figures 13 and 14, for example, the member body 11 may include a single convex portion 11C. In Figures 13 and 14, the member body 11 includes a single plate portion 111, 112, 113 and a ridge portion 114, 115, respectively. As shown in Figure 14, the member body 11 may further include two flanges 17. In these cases as well, the inward-facing flange 12 is provided in a continuous manner with at least the ridge portions 114, 115. In the example of Figures 13 and 14, the inward-facing flange 12 is provided in a continuous manner with the plate portions 111, 112, 113 and the ridge portions 114, 115. In the examples shown in Figures 13 and 14, the inward-facing flange 12 may be provided at one end edge of the member body 11 in the direction of extension of the ridge portions 114 and 115, or it may be provided at both end edges of the member body 11. Similarly, in the energy absorbing member 10A according to the second embodiment, the member body 11 may include a single convex portion 11C. 【0070】 In the energy absorbing member 10 according to the first embodiment described above, the plate portions 111, 112 and the ridge portion 114 of the member body 11, together with the plate portion 113 and the ridge portion 115, form a convex portion 11C. However, the member body 11 does not necessarily have to include the plate portion 113 and the ridge portion 115. For example, as shown in Figure 15, in the member body 11, the ends of the plate portions 111 and 112 opposite to the ridge portion 114 may be free ends. In this case, the inward flange 12 is provided continuously with at least the ridge portion 114. In the example of Figure 15, the inward flange 12 is provided continuously with the plate portions 111, 112 and the ridge portion 114. In the example of Figure 15 as well, the inward flange 12 may be provided at one end edge of the member body 11 in the direction of extension of the ridge portion 114, or at both end edges of the member body 11. Similarly, in the energy absorbing member 10A according to the second embodiment, the member body 11 does not necessarily have to include the plate portion 113 and the ridge portion 115. 【0071】 In the energy absorbing members 10 and 10A according to the above embodiment, the inward flange 12 includes a curved portion 121 and a straight portion 122. However, as shown in Figure 16, the inward flange 12 does not have to include a straight portion 122. In other words, the end of the curved portion 121 opposite to the member body 11 may be a free end. In this case, the length along the outer surface of the curved portion 121 becomes the protruding length of the inward flange 12. 【0072】 In the energy absorbing members 10 and 10A according to the above embodiment, the inward-facing flange 12, which is a bent portion, is provided on the convex portion 11C, while the bottom portion 16 and flange 117 are not provided with bent portions. However, bent portions may be provided on the bottom portion 16 and / or flange 117. This bent portion may be bent toward the plate portion 111 side (upper side) or toward the opposite side (lower side). [Examples] 【0073】 The present disclosure will be further described below with reference to examples. However, the present disclosure is not limited to the following examples. 【0074】 To confirm the effects of this disclosure, commercially available analysis software (LS-Dyna, manufactured by Ansys) was used to evaluate the energy absorption performance of an energy absorbing member (Figure 12) having inward-facing flanges 12 only on the ridges 114 and 115. One end of the ridges 114 and 115 in the extending direction was constrained, and a rigid plate with an inclination of 5° was impacted from the other end (the side with the inward-facing flange 12) (Example 1). For comparison, an energy absorbing member having the same shape as Example 1 except that it lacked the inward-facing flange 12 was also evaluated by impacting it with a rigid plate with an inclination of 5° from the other end, while one end of the ridges 114 and 115 in the extending direction was constrained (Comparative Example 1). The material of the energy absorbing member was assumed to be a steel plate with a Vickers hardness of 300 HV. 【0075】 Figure 17 shows the energy absorption per unit weight (EA) for Example 1 and Comparative Example 1 when the indentation amount (stroke) is 55 mm. As shown in Figure 17, in Example 1, which has an inward-facing flange 12, cross-sectional deformation was suppressed compared to Comparative Example 1, which does not have an inward-facing flange 12, and the energy absorption per unit weight was significantly increased compared to Comparative Example 1. Therefore, by providing the inward-facing flange 12 at least on the ridges 114 and 115 of the member body 11, the energy absorption performance of the energy absorption member can be improved. 【0076】 [Second Example] An analysis similar to that of the first embodiment was performed on an energy absorption member having the same shape as the energy absorption member 10A (Fig. 7) according to the second embodiment (Example 2). For comparison, an analysis similar to that of the first embodiment was performed on an energy absorption member having the same shape as that of Example 2 except for the protruding length of the inward flange 12 (Comparative Example 2). In Example 2, the protruding length Lr of the inward flange 12 at the ridge lines 114 and 115 is larger than the protruding length Lp of the inward flange 12 at the plate portions 111 and 112. Regarding the ratio of the radius of curvature R to the plate thickness t of the curved portion 121: R / t, in Example 2, R / t = 8.0 was set at the ridge lines 114 and 115, while R / t = 4.0 was set at the plate portions 111 and 112. On the other hand, in Comparative Example 2, R / t = 4.0 was set at the ridge lines 114 and 115, while R / t = 8.0 was set at the plate portions 111 and 112. In Comparative Example 2, the protruding length Lr of the inward flange 12 at the ridge lines 114 and 115 is smaller than the protruding length Lp of the inward flange 12 at the plate portions 111 and 112. The material of the energy absorption member was assumed to be the same steel plate as in the first embodiment. 【0077】 For Example 2 and Comparative Example 2, the energy absorption amount (EA) at the time when the pushing-in amount (stroke) is 20 mm is shown in Fig. 18. As shown in Fig. 18, in Comparative Example 2 where Lr < Lp, the energy absorption amount decreased compared to Example 2 where Lr ≥ Lp. Therefore, it can be said that by making the protruding length Lr of the inward flange 12 at the ridge lines 114 and 115 equal to or greater than the protruding length Lp of the inward flange 12 at the plate portions 111 and 112, the energy absorption of the energy absorption member is likely to be improved. 【0078】 [Third Example] The same analysis as in the first embodiment was performed on an energy absorbing member having an L-shape in side view (Figure 15) and an energy absorbing member having a hat shape in side view (Figure 14) (Examples 3-1 and 3-2). In this analysis, inward-facing flanges 12 were provided at both ends of the member body 11 in the extending direction of the ridges 114 and 115. For comparison, the same analysis as in the first embodiment was performed on energy absorbing members having the same shape as in Examples 3-1 and 3-2, except that they lacked the inward-facing flanges 12 (Comparative Examples 3-1 and 3-2). The material of the energy absorbing member was assumed to be the same steel plate as in the first embodiment. 【0079】 Figure 19 shows the energy absorption amount (EA) at a stroke of 20 mm for each of the examples and comparative examples. As shown in Figure 19, in Example 3-1, which has an inward-facing flange 12, cross-sectional deformation was suppressed compared to Comparative Example 3-1, which does not have an inward-facing flange 12, and the energy absorption amount was significantly increased compared to Comparative Example 3-1. Similarly, in Example 3-2, which has an inward-facing flange 12, cross-sectional deformation was suppressed compared to Comparative Example 3-2, which does not have an inward-facing flange 12, and the energy absorption amount was significantly increased compared to Comparative Example 3-2. Therefore, it can be seen that even for energy absorbing members having shapes other than a wave shape in side view, the energy absorption performance is improved by providing an inward-facing flange 12 on the member body 11. 【0080】 [Fourth embodiment] For an energy absorbing member (Figures 11A and 11B) having a wave-like shape in side view and inward-facing flanges 12 at both ends of the member body 11, the same analysis as in the first embodiment was performed while changing the ratio of the radius of curvature R of the curved portion 121 of the inward-facing flange 12 to the plate thickness t. The material of the energy absorbing member was assumed to be the same steel plate as in the first embodiment. 【0081】 Figure 20 shows the energy absorption amount (EA) at a stroke of 55 mm for each of the examples and comparative examples. As shown in Figure 20, a relatively high energy absorption amount could be secured when R / t ≤ 15.0. Therefore, it is preferable that the radius of curvature R and plate thickness t of the curved portion 121 of the inward flange 12 satisfy R / t ≤ 15.0. [Explanation of symbols] 【0082】 10,10A: Energy absorbing member 11: Main component 111: Board section (First board section) 112: Board section (Second board section) 113: Board section (3rd board section) 114: Ridge section (First ridge section) 115: Ridge section (Second ridge section) 11C: Convex part 12: Inward flange 121: Curved section 111: Board section (First board section)

Claims

[Claim 1] An energy absorbing member for vehicles, A member body including a first plate portion, a second plate portion, and a first ridge portion connecting the first plate portion and the second plate portion, An inward-facing flange is provided on the edge of the member body in the extending direction of the first ridge portion, and is at least continuous with the first ridge portion and protrudes inward from the member body when viewed along the extending direction, Equipped with, An energy absorbing member that satisfies Lp ≥ 0 mm, Lr > 0 mm, and Lr ≥ Lp, where Lp is the protruding length of the inward-facing flange in the first plate portion and the second plate portion, and Lr is the protruding length of the inward-facing flange in the first ridge portion. [Claim 2] An energy absorbing member according to claim 1, The inward-facing flange includes a curved portion adjacent to the end edge of the member body, which has a curved shape that is convex outward from the energy absorbing member in a cross-sectional view. An energy absorbing member that satisfies R / t ≤ 15.0, where R is the radius of curvature of the curved portion and t is the plate thickness of the member body. [Claim 3] An energy absorbing member according to claim 1, The inward-facing flange is an energy-absorbing member that is continuous with at least one of the first plate portion and the second plate portion and the first ridge portion. [Claim 4] An energy absorbing member according to claim 1, The member body further includes a third plate portion disposed on the opposite side of the second plate portion from the first plate portion, and a second ridge portion connecting the first plate portion and the third plate portion, thereby providing an energy absorbing member. [Claim 5] The energy absorbing member according to claim 4, The member body includes a plurality of convex portions, each comprising the first plate portion, the second plate portion, the third plate portion, the first ridge portion, and the second ridge portion. An energy absorbing member in which the plurality of convex portions are arranged and connected such that the second plate portion on one of two adjacent convex portions faces the third plate portion on the other of the two convex portions. [Claim 6] An energy absorbing member according to claim 1, The energy absorbing member is an energy absorbing member having a Vickers hardness of 300 HV or more.

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