Impact absorbing structure and bumper core material

Abstract

This impact absorbing structure is provided with: first and second support parts arranged to be separated from each other; and a plurality of deformation parts coupled to the first and second support parts via first and second corresponding coupling parts, which are first and second coupling parts respectively corresponding to the first and second support parts. Each of the plurality of deformation parts has: first and second beam portions that extend linearly while inclining to the same side with respect to a corresponding straight line passing through the first corresponding coupling part and the second corresponding coupling part, as separation distance increases from the first and second corresponding coupling parts; and a third beam portion that is connected to ends of the first and second beam portions on the sides opposite to the first and second corresponding coupling parts, and that extend in a curved shape protruding to the side approaching the corresponding straight line.

Description

Impact absorbing structures and bumper core materials

[0001] The present disclosure relates to an impact absorbing structure and a bumper core material.

[0002] Patent Document 1 discloses a bumper core material made of a polypropylene-based resin foam. This bumper core material is provided, for example, inside the front bumper of an automobile vehicle, and when the vehicle collides with an object in front of it, it deforms so as to crush itself, thereby absorbing the collision energy and protecting the vehicle body and occupants inside the vehicle.

[0003] Japanese Patent Application Laid-Open No. 2004-168077

[0004] The bumper core material disclosed in Patent Document 1 is made of a polypropylene-based resin foam, and therefore can prevent a large impact force from being applied to a pedestrian in the event of a collision with the pedestrian, but the amount of energy that can be absorbed by its own deformation is small, so there is a risk that it will not be able to prevent damage to the vehicle when the vehicle collides with an object. Therefore, in order to achieve both increased collision safety when a vehicle collides with a person and greater prevention of vehicle damage by absorbing collision energy, it is necessary to devise an impact absorption structure that can be used for a bumper core material or the like, which can ensure a larger amount of absorbable collision energy while suppressing the reaction force generated in the early stages of a collision.

[0005] According to a first aspect of the present disclosure, there is provided an impact absorbing structure comprising first and second support portions arranged at a distance from each other, and a plurality of deformation portions connected to the first and second support portions via first and second corresponding connection portions, which are corresponding first and second connection portions, respectively. Each of the plurality of deformation portions has first and second beam portions that extend linearly while inclining toward the same side with respect to a corresponding straight line passing through the first and second corresponding connection portions as they move away from the first and second corresponding connection portions, and a third beam portion that is connected to the ends of the first and second beam portions opposite the first and second corresponding connection portions and extends in a convex curve toward the side approaching the corresponding straight line, and at least some of the plurality of deformation portions are arranged so that any number of first deformation portions that extend while inclining toward one side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions and second deformation portions that extend while inclining toward the other side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions are alternately arranged.

[0006] According to a second aspect of the present disclosure, there is provided a shock absorbing structure including first and second support portions arranged at a distance from each other, and a plurality of deforming portions connected to the first and second support portions via first and second corresponding connection portions, which are corresponding first and second connection portions, respectively. The plurality of deforming portions each include first and second beam portions that extend linearly while inclining toward the same side with respect to a corresponding line passing through the first and second corresponding connection portions as they move away from the first and second corresponding connection portions, and a third beam portion that is connected to ends of the first and second beam portions opposite the first and second corresponding connection portions and extends in a curved shape that is convex toward the corresponding line. Each of the plurality of deforming portions is connected to at least one of the first and second support portions and is inclined toward the corresponding line. When a load is applied in a direction along the line ⑧, as the displacement of the distance between the first and second support portions increases, the curvature of the third beam portion decreases as the inclination angle of the first and second beam portions with respect to the corresponding straight line increases until a portion of each of the first and second beam portions abuts against the first and second support portions, and the curvature of the third beam portion increases in a second stage while the portion of each of the first and second beam portions abuts against the first and second support portions.

[0007] According to a third aspect of the present disclosure, there is provided an impact absorbing structure comprising first and second support portions arranged at a distance from each other, and a plurality of deformation portions connected to the first and second support portions via first and second corresponding connection portions, which are corresponding first and second connection portions, respectively. The multiple deformation portions each have first and second beam portions that extend linearly while inclining toward the same side with respect to a corresponding line passing through the first and second corresponding connection portions as they move away from the first and second corresponding connection portions, and a third beam portion that is connected to the ends of the first and second beam portions opposite the first and second corresponding connection portions and extends in a convex curve toward the corresponding line, and the shock absorbing structure is configured to exhibit, when a load is applied to at least one of the first and second support portions in a direction along the corresponding line, a first displacement region in which the displacement amount increases while maintaining a first reaction force band, and a second displacement region in which the displacement amount increases while maintaining a second reaction force band that is larger than the first reaction force band.

[0008] According to a fourth aspect of the present disclosure, there is provided a shock absorbing structure including first and second support portions spaced apart from each other in a first direction, and a pair of deforming portions provided between the first support portion and the second support portion, wherein the pair of deforming portions includes a pair of first linear beam portions extending from the first support portion in the first direction so as to gradually increase the distance between them, a pair of second linear beam portions extending from the second support portion in a direction opposite to the first direction so as to gradually increase the distance between them, and a pair of arc-shaped beam portions provided between the pair of first linear beam portions and the pair of second linear beam portions and arranged so that the convex portions of the arcs face each other, and the shock absorbing structure is configured to generate a first displacement region that displaces while maintaining a first reaction force band and a second displacement region that displaces while maintaining a second reaction force band larger than the first reaction force band when a load is applied to the first support portion or the second support portion in the first direction.

[0009] Other features and advantages of the present disclosure can be seen from the following description and the accompanying drawings, which are given by way of example and are not exhaustive.

[0010] FIG. 1 is a front view showing a shock absorbing structure according to an embodiment of the present disclosure. FIG. 2 is a diagram showing a load-displacement curve representing the relationship between a load applied from above to the shock absorbing structure shown in FIG. 1 and the amount of displacement of the shock absorbing structure. FIG. 3 is a diagram showing the deformation state of the shock absorbing structure at a characteristic stage of the load-displacement curve shown in FIG. 2. FIG. 4 is a perspective view showing an example of a bumper core material including a shock absorbing structure according to an embodiment of the present disclosure. FIG. 5 is a front view showing a shock absorbing structure according to another embodiment of the present disclosure. FIG. 6 is a diagram showing a load-displacement curve representing the relationship between a load applied from above to the shock absorbing structure shown in FIG. 6 and the amount of displacement of the shock absorbing structure. FIG. 7 is a diagram showing the deformation state of the shock absorbing structure at a characteristic stage of the load-displacement curve shown in FIG. 8. FIG. 9 is a front view showing a shock absorbing structure according to another embodiment of the present disclosure.

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0012] First, a configuration of a shock absorbing structure 100 according to an embodiment of the present disclosure will be described. Fig. 1 is a front view showing a shock absorbing structure according to an embodiment of the present disclosure.

[0013] As shown in Fig. 1, the shock absorbing structure 100 of this embodiment has first and second support portions 110, 120 arranged at an interval from each other, and first and second deformable portions 130, 140 provided between the first and second support portions 110, 120. The shock absorbing structure 100 is formed as a single unit by these members 110 to 140. Note that Fig. 1 schematically shows the cross-sectional shapes of the members 110 to 140 that appear on the front of the shock absorbing structure 100, and these members 110 to 140 have a thickness and a depth toward the rear of the paper surface of Fig. 1.

[0014] The first and second deforming portions 130, 140 each have a first linear beam portion (first beam portion) 132, 142, a second linear beam portion (second beam portion) 134, 144, and first and second arc-shaped beam portions (third beam portions) 136, 146 provided between the first linear beam portion 132, 142 and the second linear beam portion 134, 144. The first linear beam portions 132, 142 have one end fixed to the first support portion 110 via first fixing portions (first corresponding connection portions) 133, 143, respectively, and extend such that the spacing between them increases with increasing distance from the first support portion 110. Similarly, the second linear beam portions 134, 144 each have one end fixed to the second support portion 120 via a second fixing portion (second corresponding connection portion) 135, 145, and extend such that the distance between them increases as they move away from the second support portion 120. The first and second arc-shaped beam portions 136, 146 are arranged so that the convex sides of their arcs face each other. In this way, the first and second deforming portions 130, 140 are arranged so that they are mirror images of each other.

[0015] The first and second deforming portions 130, 140 are described in more detail below. The first and second deforming portions 130, 140 are arranged side by side in the left-right direction in Fig. 1 . In the first deforming portion 130, the first and second linear beam portions 132, 134 extend while inclining toward the same side (left side in Fig. 1 ) with respect to a corresponding straight line L1 (see the dashed line in Fig. 1 ) passing through the first and second fixed portions 133, 135 as they move away from the first and second fixed portions 133, 135. The first arc-shaped beam portion 136 is connected to the ends of the first and second linear beam portions 132, 134 opposite the first and second fixed portions 133, 135, and extends in a convex arc shape toward the side approaching the corresponding straight line L1 (right side in Fig. 1 ). In the second deformation portion 140, the first and second linear beam portions 142, 144 extend while inclining toward the same side (the right side in FIG. 1 ) of a corresponding straight line L2 (see the two-dot chain line in FIG. 1 ) passing through the first and second fixed portions 143, 145 as they move away from the first and second fixed portions 143, 145, and the second arc-shaped beam portion 146 is connected to the ends of the first and second linear beam portions 142, 144 opposite the first and second fixed portions 143, 145, and extends in a convex arc toward the side approaching the corresponding straight line L2 (the left side in FIG. 1 ). The corresponding straight lines L1, L2 are parallel to each other. The first and second linear beam portions 132, 134 of the first deformation portion 130 and the first and second linear beam portions 142, 144 of the second deformation portion 140 are all the same length and extend linearly with the same inclination relative to the corresponding lines L1, L2. The first and second arc-shaped beam portions 136, 146 extend arc-like with the same curvature. Note that the first and second arc-shaped beam portions 136, 146 are not limited to being arc-shaped as long as they are curved, and may be, for example, elliptical arc-shaped or sinusoidal.

[0016] In each of the deformation portions 130, 140, it is preferable that the first linear beam portion 132, 142, the second linear beam portion 134, 144, and the first and second arcuate beam portions 136, 146 between the first linear beam portion 132, 142 and the second linear beam portion 134, 144 are integrally molded, and further it is preferable that each of the deformation portions 130, 140 is also integrally molded with the first and second support portions 110, 120. The shock absorbing structure 100 of the present embodiment can be configured as an integrally molded member that is integrally molded by, for example, injection molding, blow molding, extrusion molding, or 3D printing of a resin material, or casting, forging, pressing, cutting, extrusion molding, or 3D printing of a metal material. Alternatively, in the shock absorption structure 100 of this embodiment, the beam portions in each of the deformation portions 130, 140 may be joined or fastened to each other by any fastening means such as adhesive, welding, bolting or riveting, and further, each of the deformation portions 130, 140 and the first and second support portions 110, 120 may be joined or fastened to each other by similar means.

[0017] Fig. 2 is a diagram showing a load-displacement curve representing the relationship between a load (reaction force of the shock absorption structure 100) applied from above to the shock absorption structure 100 shown in Fig. 1 and the amount of displacement of the shock absorption structure 100 (amount of displacement of the distance between the first and second support parts 110, 120). Fig. 3 is a diagram showing the deformation state of the shock absorption structure 100 at characteristic stages of the load-displacement curve shown in Fig. 2.

[0018] Here, a description will be given of a specific example of the shock absorbing structure 100 of this embodiment. In this example, as an example, each component of the shock absorbing structure 100 is configured in accordance with the following requirements. (Material) Polycarbonate (Dimensions) Overall dimensions of structure 100: width (left-right direction in the figure) 33.4 mm, depth (direction on the paper surface in the figure) 150 mm, height (up-down direction in the figure) 80 mm Thickness of each member 110-140: 2.5 mm Length of straight beam portions 132, 134; 142, 144: 29.1 mm Radius and arc length of arc-shaped beams 136, 146: radius 13.8 mm, arc length 30.8 mm Spacing between first straight beam portions 132, 142 at the connection portion with first support portion 110 (distance between the centers of each beam portion): 6 mm Spacing between second straight beam portions 134, 144 at the connection portion with second support portion 120 (distance between the centers of each beam portion): 6 mm

[0019] 2 and 3 show the results of a simulation of the load (reaction force) of the shock absorption structure 100 and the amount of displacement in the vertical direction when a load is applied from above to the shock absorption structure 100 configured in accordance with the above requirements. As a result of the simulation, the inventors confirmed that the shock absorption structure 100 deforms in the following order: first stage, then second stage.

[0020] In the first stage of deformation of the shock absorption structure 100, as shown in Figures 3(A) to 3(c), due to the deformation of the first linear beam portions 132, 142, the second linear beam portions 134, 144, and the first and second arcuate beam portions 136, 146, the inclination angles of the first linear beam portions 132, 142 and the second linear beam portions 134, 144 with respect to the corresponding lines L1, L2 gradually increase while the curvature of the first and second arcuate beam portions 136, 146 gradually decreases, so that a portion of each of the first linear beam portions 132, 142 abuts against the first support portion 110 and a portion of each of the second linear beam portions 134, 144 abuts against the second support portion 120. In this first stage of deformation, as shown in FIG. 2, in the region where the displacement is 0 mm to approximately 10 mm, the load (reaction force) and the displacement increase gradually and approximately linearly as the displacement increases, and in the region where the displacement is approximately 10 mm to 42 mm, the load remains at approximately 1800 N to 2500 N even when the displacement increases.

[0021] 3(C) to 3(E), in a state in which a portion of each of the first linear beam portions 132, 142 abuts against the first support portion 110 and a portion of each of the second linear beam portions 134, 144 abuts against the second support portion 120, the curvature of the first and second arcuate beam portions 136, 146 gradually increases due to the deformation of the first and second arcuate beam portions 136, 146. In this second stage of deformation, as shown in FIG. 2, in the region of approximately 42 mm to approximately 50 mm of displacement, the load (reaction force) and the displacement gradually increase in a substantially linear manner as the displacement increases, and in the region of approximately 50 mm to approximately 60 mm of displacement, the load remains at approximately 5500 N to 6000 N even when the displacement increases.

[0022] When the deformation of the shock absorbing structure 100 progresses further and reaches a bottoming-out state where it no longer deforms, the amount of displacement does not increase and only the load increases.

[0023] As described above, the impact absorption structure 100 of this embodiment provides a load-displacement characteristic having two deformation regions: a first displacement region (a region of approximately 10 mm to approximately 42 mm in FIG. 2 ) in which the impact is displaced while being substantially maintained in a first reaction force band where the reaction force against the load is relatively low; and a second displacement region (a region of approximately 50 mm to approximately 60 mm in FIG. 2 ) in which the impact is displaced while being substantially maintained in a second reaction force band where the reaction force against the load is relatively high. Therefore, the first displacement region can suppress the reaction force, while the second displacement region can absorb more of the collision energy. In other words, the amount of absorbable collision energy can be increased while suppressing the reaction force generated at the initial stage of a collision. Therefore, when the impact absorption structure 100 is used as a core material for a vehicle bumper, the first displacement region can suppress the impact on a pedestrian because the reaction force is relatively small, and the second displacement region can absorb more of the vehicle collision energy. As a result, it is possible to achieve both improved collision safety for people when a vehicle collides with them and better protection for the vehicle and its occupants by absorbing collision energy.

[0024] FIG. 4 is a perspective view showing an example of a bumper core material 200 including the shock absorbing structure 100 of this embodiment.

[0025] As shown in Figure 4, the bumper core material 200 has a configuration in which the impact absorbing structures 100 of this embodiment are arranged in parallel in a row. The bumper core material 200 has a first side surface portion 210 and a second side surface portion 220, which also serve as the first and second support portions 110, 120 of the impact absorbing structure 100. By disposing the bumper core material 200 configured in this manner on the back side of the bumper of a vehicle, as described above, it is possible to increase the collision safety of people when the vehicle collides with them and to absorb collision energy to protect the vehicle and occupants in the vehicle.

[0026] In the above-described embodiment, the first and second deforming portions 130, 140 are arranged in this order from the left side of the shock absorbing structure 100 shown in Fig. 1 , but the present invention is not limited to this. For example, shock absorbing structures 100B, 100C shown in Fig. 5 and Fig. 6 may also be used.

[0027] The shock absorbing structure 100B shown in Fig. 5 differs from the shock absorbing structure 100 shown in Fig. 1 in that the positions of the first and second deforming portions 130, 140 in the left-right direction in the figure are swapped. That is, in the shock absorbing structure 100B, the second and first deforming portions 140, 130 are arranged side by side in this order from the left side in the figure. The shock absorbing structure 100 and the shock absorbing structure 100B are identical to each other except for the swapped positions in the left-right direction in the figure, and therefore the shock absorbing structure 100B can achieve the same effects as the shock absorbing structure 100.

[0028] The shock absorption structure 100C shown in Fig. 6 differs from the shock absorption structure 100 shown in Fig. 1 in that the first deforming portion 130 is replaced with a second deforming portion 140. That is, in the shock absorption structure 100C, two second deforming portions 140 are arranged side by side in the left-right direction in the figure. When the shock absorption structure 100C is viewed from the back, it can be said that two first deforming portions 130 are arranged side by side in the left-right direction in the figure.

[0029] Fig. 7 is a diagram showing a load-displacement curve representing the relationship between a load applied from above to the shock absorption structure 100C shown in Fig. 6 and the amount of displacement of the shock absorption structure 100C. Fig. 8 is a diagram showing a deformation state of the shock absorption structure 100C at a characteristic stage of the load-displacement curve shown in Fig. 7. In the embodiment, as an example, the shock absorption structure 200B is configured according to the same requirements as the shock absorption structure 100 described above.

[0030] 7 and 8 show the results of a simulation of the load (reaction force) and the displacement in the vertical direction of the shock absorption structure 100C when a load is applied from above in the figure to a shock absorption structure 100C configured according to the same requirements as the shock absorption structure 100. A comparison of FIGS. 2 and 7 and also of FIGS. 3 and 8 reveals that the first and second stages in the simulation results for the shock absorption structure 100 correspond to the first to fourth and second stages in the simulation results for the shock absorption structure 100C, and that FIGS. 3(A) to 3(E) and FIGS. 8(A) to 8(E) correspond to each other. Therefore, the shock absorption structure 100C shown in FIG. 6 can also achieve the same effects as the shock absorption structure 100 shown in FIG. 1.

[0031] The shock absorbing structure 100C is provided with two second deformation portions 140 (first deformation portions 130 when viewed from the rear surface), but may be provided with three or more.

[0032] In the above-described embodiment, as in the shock absorbing structures 100 and 100B shown in Fig. 1 and Fig. 5, one first deforming portion 130 and one second deforming portion 140 are arranged to be mirror images of each other, but this is not limited to this. For example, as in the shock absorbing structure 100D shown in Fig. 9, a plurality of first deforming portions 130 (three in Fig. 9) and the same number of second deforming portions 140 may be arranged to be mirror images of each other. Furthermore, the number of first deforming portions 130 and the number of second deforming portions 140 may be different.

[0033] In the above-described embodiment, the shock absorbing structure 100, 100B shown in FIG. 1 or FIG. 5 includes one set of first and second deformable portions 130, 140. However, this is not limiting. For example, multiple sets of the first and second deformable portions 130, 140 of the shock absorbing structure 100 may be arranged side by side (see FIG. 4). Also, multiple sets of the first and second deformable portions 130, 140 of the shock absorbing structure 100B may be arranged side by side. Furthermore, n1 (n1≧1) sets of the first and second deformable portions 130, 140 of the shock absorbing structure 100 and n2 (n2≧1) sets of the first and second deformable portions 130, 140 of the shock absorbing structure 100B may be arranged side by side in any order. At least one of n3 (n3≧1) first deformable portions 130 and n4 (n4≧1) second deformable portions 140 may be added to these.

[0034] In the above-described embodiment, the first deformation portion 130 and / or the second deformation portion 140 are arranged side by side in the left-right direction of the figure, as in the shock absorbing structures 100, 100B, 100C, 100D shown in Figures 1, 5, 6, and 9, but in addition to or instead of this, the first deformation portion 130 and / or the second deformation portion 140 may be arranged side by side in a direction penetrating the paper surface, for example.

[0035] In the above-described embodiment, the first and second support portions 110, 120 are linear (flat) and have a constant distance from each other, as in the shock absorbing structures 100, 100B, and 100C shown in FIGS. 1, 5, and 6. However, this is not limiting. For example, the first and second support portions 110, 120 may be curved (see FIG. 4). Additionally or alternatively, the distance between the first and second support portions 110, 120 may not be constant. For example, as in the shock absorbing structure 100E shown in FIG. 10, the second support portion 120 may have a step, so that the distance between the first and second support portions 110, 120 is not constant.

[0036] Although the present disclosure has been described above through the disclosed embodiments and examples, the above-described embodiments and examples do not limit the invention according to the claims. Furthermore, combinations of the features described in the embodiments and examples of the present disclosure may also be included within the technical scope of the present disclosure.

[0037] [Notes] [1] A first shock absorbing structure of the present disclosure is a shock absorbing structure including first and second support parts arranged at intervals from each other, and a plurality of deforming parts connected to the first and second support parts via first and second corresponding connection parts that are corresponding first and second connection parts, respectively, wherein the plurality of deforming parts are each made up of first and second beam parts that extend linearly while inclining toward the same side with respect to a corresponding line that passes through the first corresponding connection part and the second corresponding connection part as they move away from the first and second corresponding connection parts, and The gist of the invention is that the device has a third beam portion connected to an end opposite to the first and second corresponding connection portions and extending in a convex curve toward the corresponding straight line, and at least some of the multiple deformation portions are arranged so that any number of first deformation portions extend while inclining toward one side of the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions, and second deformation portions extend while inclining toward the other side of the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions.

[0038] In the first impact absorption structure of the present disclosure, the plurality of deformation portions each include first and second beam portions that extend linearly while inclining toward each other with respect to a corresponding line passing through the first and second corresponding connection portions as they move away from the first and second corresponding connection portions, and a third beam portion that is connected to ends of the first and second beam portions opposite the first and second corresponding connection portions and extends in a convex curve toward the corresponding line. At least some of the plurality of deformation portions are arranged so that any number of first deformation portions that extend while inclining toward one side with respect to the corresponding line as the first and second beam portions move away from the first and second corresponding connection portions and second deformation portions that extend while inclining toward the other side with respect to the corresponding line as the first and second beam portions move away from the first and second corresponding connection portions are alternately arranged. This makes it possible to suppress the reaction force generated at the initial stage of a collision while ensuring a greater amount of absorbable collision energy. The inventors confirmed this through simulations and the like.

[0039] [2] In the first shock absorbing structure of the present disclosure (the shock absorbing structure described in [1] above), the plurality of deformation portions may have an equal number of first deformation portions that extend while inclining toward one side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions, and second deformation portions that extend while inclining toward the other side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions.

[0040] [3] A second shock absorbing structure of the present disclosure is a shock absorbing structure including first and second support parts arranged at intervals from each other, and a plurality of deforming parts connected to the first and second support parts via first and second corresponding connection parts that are corresponding first and second connection parts, respectively, wherein the plurality of deforming parts each include first and second beam parts that extend linearly while inclining toward the same side with respect to a corresponding line that passes through the first and second corresponding connection parts as they move away from the first and second corresponding connection parts, and first and second beam parts that are connected to ends of the first and second beam parts opposite the first and second corresponding connection parts and have a convex curve on the side approaching the corresponding line. and a third beam portion extending linearly, and each of the plurality of deformation portions is configured to deform in the following order when a load is applied to at least one of the first and second support portions in a direction along the corresponding straight line: a first stage in which the curvature of the third beam portion decreases as the inclination angle of the first and second beam portions with respect to the corresponding straight line increases until a portion of each of the first and second beam portions abuts against the first and second support portions as the displacement of the distance between the first and second support portions increases; and a second stage in which the curvature of the third beam portion increases with a state in which a portion of each of the first and second beam portions abuts against the first and second support portions.

[0041] In the second shock absorption structure of the present disclosure, the multiple deformation portions each have first and second beam portions that extend linearly while inclining toward the same side with respect to a corresponding straight line passing through the first and second corresponding connection portions as they move away from the first and second corresponding connection portions, and a third beam portion that is connected to the ends of the first and second beam portions opposite the first and second corresponding connection portions and extends in a convex curve toward the side approaching the corresponding straight line. The plurality of deformation portions are configured to deform in the following order when a load is applied to at least one of the first and second support portions in a direction along the corresponding line: (1) a first stage in which the curvature of the third beam portion decreases as the inclination angle of the first and second beam portions with respect to the corresponding line increases until a portion of each of the first and second beam portions abuts against the first and second support portions as the displacement of the distance between the first and second support portions increases; and (2) a second stage in which the curvature of the third beam portion increases in a state in which a portion of each of the first and second beam portions abuts against the first and second support portions. This makes it possible to suppress the reaction force generated at the initial stage of a collision while ensuring a greater amount of absorbable collision energy. The inventors confirmed this through simulations and other means.

[0042] [4] A third shock absorbing structure of the present disclosure is a shock absorbing structure including first and second support parts arranged at intervals from each other, and a plurality of deforming parts connected to the first and second support parts via first and second corresponding connection parts that are corresponding first and second connection parts, respectively, wherein the plurality of deforming parts each include first and second beam parts that extend linearly while inclining toward the same side with respect to a corresponding line that passes through the first and second corresponding connection parts as they move away from the first and second corresponding connection parts; The shock absorbing structure has a third beam portion connected to the ends of the first and second beam portions opposite the first and second corresponding connection portions and extending in a convex curve toward the corresponding straight line, and is configured to exhibit a first displacement region in which the displacement amount increases while maintaining a first reaction force band, and a second displacement region in which the displacement amount increases while maintaining a second reaction force band larger than the first reaction force band, when a load is applied to at least one of the first and second support portions in a direction along the corresponding straight line.

[0043] In a third impact absorption structure according to the present disclosure, the plurality of deformation portions each include first and second beam portions extending linearly and inclining toward the same side with respect to a corresponding line passing through the first and second corresponding connection portions as they move away from the first and second corresponding connection portions, and a third beam portion connected to ends of the first and second beam portions opposite the first and second corresponding connection portions and extending in a convex curve toward the corresponding line. When a load is applied to at least one of the first and second support portions in a direction along the corresponding line, the impact absorption structure exhibits a first displacement region in which a displacement amount increases while maintaining a first reaction force band, and a second displacement region in which the displacement amount increases while maintaining a second reaction force band larger than the first reaction force band. This arrangement can reduce the reaction force generated at the initial stage of a collision while ensuring a greater amount of absorbable impact energy. The inventors confirmed this through simulations and other means.

[0044] [5] In any of the first to third shock absorbing structures of the present disclosure (the shock absorbing structure described in any of [1] to [4] above), the shock absorbing structure may be integrally molded.

[0045] [6] The bumper core material of the present disclosure is characterized in that it includes any one of the first to third shock absorbing structures of the present disclosure (the shock absorbing structures described in any one of [1] to [5] above). Therefore, it can achieve the same effects as those achieved by the first to third shock absorbing structures of the present disclosure.

[0046] [7] A fourth shock absorbing structure of the present disclosure is a shock absorbing structure including first and second support parts spaced apart from each other in a first direction, and a pair of deforming parts provided between the first support part and the second support part, wherein the pair of deforming parts includes a pair of first linear beam parts extending from the first support part in the first direction so that the distance therebetween gradually increases, and a pair of second linear beam parts extending from the second support part in a direction opposite to the first direction so that the distance therebetween gradually increases. The shock absorbing structure has a linear beam portion and a pair of arc-shaped beam portions provided between the pair of first linear beam portions and the pair of second linear beam portions, and arranged so that the convex portions of each arc face each other, and is configured to provide a first displacement region that displaces while maintaining a first reaction force band, and a second displacement region that displaces while maintaining a second reaction force band that is larger than the first reaction force band, when a load is applied to the first support portion or the second support portion along the first direction.

[0047] In a fourth impact absorption structure of the present disclosure, the pair of deformation portions includes a pair of first linear beam portions extending from the first support portion in a first direction such that the distance between them gradually increases, a pair of second linear beam portions extending from the second support portion in a direction opposite to the first direction such that the distance between them gradually increases, and a pair of arc-shaped beam portions disposed between the pair of first linear beam portions and the pair of second linear beam portions and arranged such that the convex portions of the arcs face each other. The impact absorption structure is configured to provide a first displacement region that displaces while maintaining a first reaction force band and a second displacement region that displaces while maintaining a second reaction force band larger than the first reaction force band when a load is applied to the first support portion or the second support portion in the first direction. This makes it possible to suppress the reaction force generated at the initial stage of a collision while more sufficiently ensuring the amount of impact energy that can be absorbed. The inventors confirmed this through simulations and other means.

[0048] [8] In the fourth shock absorbing structure of the present disclosure (the shock absorbing structure described in [7] above), the shock absorbing structure may be integrally molded.

Claims

1. A shock absorbing structure comprising: first and second support parts arranged at a distance from each other; and a plurality of deformation parts connected to the first and second support parts via first and second corresponding connection parts which are corresponding first and second connection parts, respectively, wherein the plurality of deformation parts each have: first and second beam parts which extend linearly while being inclined toward the same side with respect to a corresponding straight line passing through the first corresponding connection part and the second corresponding connection part as they move away from the first and second corresponding connection parts; and a third beam part which is connected to the ends of the first and second beam parts opposite the first and second corresponding connection parts and extends in a curved shape which is convex toward the side approaching the corresponding straight line, At least a portion of the plurality of deformation portions are arranged so that any number of first deformation portions extend while inclining to one side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions, and second deformation portions extend while inclining to the other side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connection portions.

2. A shock absorbing structure as described in claim 1, wherein the plurality of deformation portions have an equal number of first deformation portions which extend while inclining to one side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connecting portions, and second deformation portions which extend while inclining to the other side with respect to the corresponding straight line as the first and second beam portions move away from the first and second corresponding connecting portions.

3. A shock absorbing structure comprising: first and second support parts arranged at a distance from each other; and a plurality of deformation parts connected to the first and second support parts via first and second corresponding connection parts which are corresponding first and second connection parts, respectively, wherein the plurality of deformation parts each have: first and second beam parts which extend linearly while inclining toward the same side with respect to a corresponding line passing through the first corresponding connection part and the second corresponding connection part as they move away from the first and second corresponding connection parts; and a third beam part which is connected to the ends of the first and second beam parts opposite the first and second corresponding connection parts and extends in a curved shape which is convex toward the side approaching the corresponding line, and wherein, when a load is applied to at least one of the first and second support parts in a direction along the corresponding line, each of the plurality of deformation parts: a first stage in which the curvature of the third beam portion decreases as the inclination angles of the first and second beam portions with respect to the corresponding straight line increase until a portion of each of the first and second beam portions abuts against the first and second support portions; and a second stage in which the curvature of the third beam portion increases with a portion of each of the first and second beam portions abutting against the first and second support portions.

4. A shock absorbing structure comprising: first and second support parts arranged at a distance from each other; and a plurality of deformation parts connected to the first and second support parts via first and second corresponding connection parts which are corresponding first and second connection parts, respectively, wherein the plurality of deformation parts each have: first and second beam parts extending linearly while inclining toward the same side with respect to a corresponding line passing through the first corresponding connection part and the second corresponding connection part as they move away from the first and second corresponding connection parts; and a third beam part connected to the end of the first and second beam parts opposite the first and second corresponding connection parts and extending in a curved shape convex toward the side approaching the corresponding line, and the shock absorbing structure is configured to present, when a load is applied to at least one of the first and second support parts in a direction along the corresponding line, a first displacement region in which a displacement amount increases while maintaining a first reaction force band, and a second displacement region in which the displacement amount increases while maintaining a second reaction force band larger than the first reaction force band. Shock absorbing structure.

5. A shock absorbing structure according to any one of claims 1, 3 and 4, wherein the shock absorbing structure is integrally molded.

6. A bumper core material comprising an impact absorbing structure according to any one of claims 1, 3 and 4.

7. A shock absorbing structure comprising first and second support parts arranged at an interval from each other in a first direction, and a pair of deforming parts provided between the first support part and the second support part, wherein the pair of deforming parts comprises: a pair of first linear beam parts extending such that the interval between them gradually increases as they extend from the first support part toward the first direction, a pair of second linear beam parts extending from the second support part toward a direction opposite to the first direction, and a pair of arc-shaped beam parts provided between the pair of first linear beam parts and the pair of second linear beam parts, and arranged so that the convexities of each arc face each other, and the shock absorbing structure is configured so that, when a load is applied to the first support part or the second support part along the first direction, a first displacement region that displaces while maintaining a first reaction force band, and a second displacement region that displaces while maintaining a second reaction force band larger than the first reaction force band.

8. The shock absorbing structure according to claim 7, wherein said shock absorbing structure is integrally molded.

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