New energy automobile energy absorption structure based on following curve gradient multi-cell self-similar unit

Abstract

The invention discloses a new energy automobile energy absorption structure based on a following curve gradient multi-cell self-similar unit, which comprises a first multi-cell self-similar structure, and the first multi-cell self-similar structure comprises a gradient multi-cell self-similar unit. The gradient multi-cell self-similarity unit comprises a polygonal pipe and a plurality of similar polygonal energy absorption pipes which are arranged in the polygonal pipe and similar to the polygonal pipe, and the plurality of similar polygonal energy absorption pipes are sequentially distributed in a spiral mode along a following curve from outside to inside. The energy absorption structure of the new energy automobile has a good energy absorption effect when being impacted, deformation is stable, the energy absorption efficiency is high, a good anti-collision effect is achieved, and therefore safety is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to an energy absorption structure of a new energy vehicle based on a polyhedral self-similar unit following a curve gradient. Background Art

[0002] In recent years, the number of cars has increased, resulting in frequent car accidents. The energy-absorbing structure of the front cabin of a car is of great significance to the safety of a car collision. During a frontal collision of a car, the collision energy absorbed by the front longitudinal beam and the energy-absorbing box accounts for more than half of the collision energy of the entire vehicle, and the deformation mode and energy-absorbing characteristics of these two energy-absorbing structures have a decisive influence on the transmission path of the collision force and the acceleration response during the collision. Therefore, with the trend of increasing attention to car collision safety and lightweight body, the design of such energy-absorbing structures has become a key research technology for major automobile manufacturers and research institutes.

[0003] Thin-walled structures are widely used in anti-collision energy-absorbing parts of automobiles due to their excellent mechanical properties. Therefore, existing energy-absorbing structures are mainly thin-walled structures. Existing energy-absorbing structures are mainly used in fuel vehicles. With the development of modern new energy technologies, new energy vehicles are gradually accepted by the public. The requirements for energy-absorbing structures of new energy vehicles and fuel vehicles are relatively different. Due to the particularity of new energy batteries, the collision energy-absorbing space is small, and new energy vehicles are required to have better anti-collision performance, so as to effectively protect new energy batteries and personnel.

[0004] The existing thin-walled structures still have defects such as unstable deformation and low energy absorption efficiency when impacted; the existing thin-walled structures cannot meet the needs of new energy vehicles. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned problems and provide an energy absorption structure for new energy vehicles based on following curve gradient polyhedral self-similar units; the energy absorption structure for new energy vehicles has a good energy absorption effect when impacted, stable deformation, high energy absorption efficiency, and a good anti-collision effect, thereby improving safety.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A new energy vehicle energy absorption structure based on a curve-following gradient polyhedral self-similar unit comprises a first polyhedral self-similar structure, wherein the first polyhedral self-similar structure comprises a gradient polyhedral self-similar unit, wherein the gradient polyhedral self-similar unit comprises a polygonal tube and a plurality of similar polygonal energy absorption tubes arranged inside the polygonal tube and similar to the polygonal tube, wherein the plurality of similar polygonal energy absorption tubes are distributed in a spiral manner from outside to inside along the following curve.

[0008] The working principle of the above-mentioned energy-absorbing structure of new energy vehicles is as follows:

[0009] Multiple similar polygon energy-absorbing tubes are distributed in a spiral manner along the following curve from the outside to the inside in sequence, so that multiple similar polygon energy-absorbing tubes form a hierarchical structure. When the energy-absorbing structure of new energy vehicles is subjected to an external impact, the multiple similar polygon energy-absorbing tubes inside will absorb and disperse the impact energy, and the internal hierarchical structure will produce stacking deformation to form folds, which can quickly absorb energy and reduce the impact of the impact force on the structure.

[0010] A preferred solution of the present invention is that the side edges of the similar polygon energy-absorbing tube located in the outermost layer are connected to the inner side surface of the polygon tube; among two adjacent similar polygon energy-absorbing tubes, the side edges of the similar polygon energy-absorbing tube located in the inner layer are connected to the inner side surface of the similar polygon energy-absorbing tube located in the outer layer. In the above structure, the similar polygon energy-absorbing tube located in the outermost layer is connected to the polygon tube, and adjacent similar polygon energy-absorbing tubes are connected to each other, which can improve the strength of the energy-absorbing structure of new energy vehicles, disperse the impact energy, and improve the anti-collision effect.

[0011] Preferably, the cross-sectional shapes of the polygon tube and the similar polygon energy-absorbing tube are both polygons; any two polygons are similar polygons; among two adjacent polygons, each vertex of the polygon located in the inner layer is connected to each side of the polygon located in the outer layer one by one; the vertex is a point on the side edge of the similar polygon energy-absorbing tube. The purpose is to make the structure more stable by setting the polygon tube and the similar polygon energy-absorbing tube with a polygonal cross-sectional shape, which can improve the strength and energy-absorbing effect of the energy-absorbing structure of new energy vehicles.

[0012] Preferably, among two adjacent polygons, the vertex positions are selected on each side of the polygon located in the outer layer in the same proportion, and the vertex positions are the vertex positions of the polygon located in the inner layer. In the above structure, the purpose is to make the vertices of the polygon located on the following curve, and two adjacent polygons are connected to each other. When an external impact acts on the energy-absorbing structure of new energy vehicles, each polygon inside will absorb and disperse the impact energy, and the internal hierarchical structure will produce stacking deformation to form folds, reducing the impact of the impact force on the structure.

[0013] Preferably, both the polygonal tube and the similar polygonal energy-absorbing tube are formed by enclosing a plurality of side plates connected end to end in sequence, and each side plate corresponds to a side of the polygon one by one; at the vertex position, each side of the polygon is divided into two line segments, the longer line segment is the long line segment, and the shorter line segment is the short line segment; the part of the side plate corresponding to the long line segment is the long connecting plate, and the part of the side plate corresponding to the short line segment is the short connecting plate; the similar polygonal energy-absorbing tubes are arranged from outside to inside. When the number of similar polygonal energy-absorbing tubes is even, the long connecting plates of the similar polygonal energy-absorbing tubes in the odd layers are removed; when the number of similar polygonal energy-absorbing tubes is odd, the long connecting plates of the similar polygonal energy-absorbing tubes in the second-to-last layer and the odd layers before the second-to-last layer are removed. In the above structure, by removing some long connecting plates and retaining the short connecting plates to achieve connection, the gap between the polygonal tube and the similar polygonal energy-absorbing tube and between two similar polygonal energy-absorbing tubes can be increased, reducing the structural weight while taking into account stability and compressive resistance.

[0014] Preferably, the polygon is a triangle. The structures of the triangular polygonal tube and the similar polygonal energy-absorbing tube are simpler.

[0015] Preferably, the polygon is a quadrilateral. The energy-absorbing effect of the quadrilateral polygonal tube and the similar polygonal energy-absorbing tube is good. The quadrilateral makes the internal space of the polygonal tube and the similar polygonal energy-absorbing tube larger. During the collision process, the structures of each layer interact with each other to produce stacking deformation, and the number of folds generated becomes more and more uniform, improving the energy absorption ability while reducing the initial peak force.

[0016] Preferably, the polygon is a hexagon. The energy-absorbing effect of the hexagonal polygonal tube and the similar polygonal energy-absorbing tube is good. Adjacent hexagons are in contact and connected with good connection stability, thus improving the overall structural rigidity. When the energy-absorbing structure of a new energy vehicle is subjected to a certain impact force, more folds are generated at the contact points of adjacent hexagons. Secondly, the external impact force will be transmitted through the contact ends of adjacent hexagons. After the gap between each layer is buffered and transitioned, the impact force is effectively reduced, thereby reducing the impact on the energy-absorbing structure of the new energy vehicle and endowing it with good impact resistance and buffering ability, which is beneficial to reducing the damage caused by the impact.

[0017] Preferably, the number of the gradient multi-cell self-similar units is six; the six gradient multi-cell self-similar units are arrayed along the circumferential direction or mirror-combined with the side edges of the polygonal tube as the center, and the outer side surfaces of the polygonal tubes of two adjacent gradient multi-cell self-similar units are connected to each other. In the above structure, the polygonal tubes of the six gradient multi-cell self-similar units are integrally arranged, so that the outer shape of the entire energy absorption structure of the new energy vehicle becomes a hexagonal prism shape, and the outer side surfaces of two adjacent polygonal tubes are connected to each other, making the overall structure more compact, which is beneficial to improving the rigidity of the overall structure. During the deformation process, the structures at all levels interact with each other, increasing the number of folds generated during the deformation process, making the fold wavelength shorter and more uniform. During the collision stage, the fluctuation of the impact force is smaller, the energy absorption is greatly improved, and the collision is more stable.

[0018] Preferably, the energy absorption structure of the new energy vehicle further includes a second multi-cell self-similar structure, and the second multi-cell self-similar structure is connected in series with the first multi-cell self-similar structure; wherein, the second multi-cell self-similar structure includes a gradient multi-cell self-similar unit, and the other structures of the gradient multi-cell self-similar unit of the second multi-cell self-similar structure are the same as those of the gradient multi-cell self-similar unit of the first multi-cell self-similar structure. The difference is that the polygon of the gradient multi-cell self-similar unit of the second multi-cell self-similar structure is a hexagon. In the above structure, the first multi-cell self-similar structure formed by arraying six gradient multi-cell self-similar units along the circumferential direction is combined with the hexagonal second multi-cell self-similar structure into a whole, obtaining a series of gradient multi-cell self-similar units with following curves, effectively reducing the weight of the structure, making the structure more lightweight, and also ensuring the rigidity of the overall structure. During the collision stage, the fluctuation of the impact force is smaller, the energy absorption is greatly improved, and the collision is more stable.

[0019] The present invention has the following beneficial effects compared with the prior art:

[0020] In the energy absorption structure of the new energy vehicle in the present invention, multiple similar polygonal energy absorption tubes are sequentially distributed in a spiral manner along the following curve from the outside to the inside, so that the multiple similar polygonal energy absorption tubes form a hierarchical structure. When the energy absorption structure of the new energy vehicle is subjected to an external impact, the multiple similar polygonal energy absorption tubes inside will absorb and disperse the impact energy, and the internal hierarchical structure will produce stacking deformation and form folds, which can quickly absorb energy, reducing the influence of the impact force on the structure, having a good energy absorption effect, stable deformation, high energy absorption efficiency, and playing a good anti-collision effect, thereby improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic three-dimensional structure diagram of the first specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0022] Figure 2It is a top view of the first specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0023] Figure 3 It is a three-dimensional structure schematic diagram of the second specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0024] Figure 4 It is a top view of the second specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0025] Figure 5 It is a series of structure schematic diagrams of the first and second specific embodiments of the energy absorption structure of the new energy vehicle in the present invention.

[0026] Figure 6 It is a three-dimensional structure schematic diagram of the third specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0027] Figure 7 It is a top view of the third specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0028] Figure 8 It is a three-dimensional structure schematic diagram of the fourth specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0029] Figure 9 It is a top view of the fourth specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0030] Figure 10 It is a series of structure schematic diagrams of the third and fourth specific embodiments of the energy absorption structure of the new energy vehicle in the present invention.

[0031] Figure 11 It is a three-dimensional structure schematic diagram of the fifth specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0032] Figure 12 It is a top view of the fifth specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0033] Figure 13 It is a three-dimensional structure schematic diagram of the sixth specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0034] Figure 14 It is a top view of the sixth specific embodiment of the energy absorption structure of the new energy vehicle in the present invention.

[0035] Figure 15 It is a series of structure schematic diagrams of the fifth and sixth specific embodiments of the energy absorption structure of the new energy vehicle in the present invention.

[0036] Figure 16 Top view of the gradient multi - cell self - similar unit of the seventh specific embodiment of the energy - absorbing structure for new - energy vehicles in the present invention.

[0037] Figure 17 Stereogram of the circumferential - direction array in the seventh specific embodiment of the energy - absorbing structure for new - energy vehicles in the present invention.

[0038] Figure 18 Top view of the circumferential - direction array in the seventh specific embodiment of the energy - absorbing structure for new - energy vehicles in the present invention.

[0039] Figure 19 Stereogram of the mirror - image combination in the seventh specific embodiment of the energy - absorbing structure for new - energy vehicles in the present invention.

[0040] Figure 20 Top view of the mirror - image combination in the seventh specific embodiment of the energy - absorbing structure for new - energy vehicles in the present invention.

[0041] Figure 21 Structure schematic diagram of the eighth specific embodiment of the energy - absorbing structure for new - energy vehicles in the present invention.

[0042] Figure 22 Force - displacement curve graph of the axial impact test of six energy - absorbing structures for new - energy vehicles in the present invention and the existing - technology structure.

[0043] Figure 23 Energy - absorption curve graph of the axial impact test of six energy - absorbing structures for new - energy vehicles in the present invention and the existing - technology structure.

[0044] Figure 24 Folding - deformation process graph of the axial impact test of five energy - absorbing structures for new - energy vehicles in the present invention and the existing - technology structure.

[0045] Figure 25 Result - comparison graph of the energy - absorption evaluation parameters of six energy - absorbing structures for new - energy vehicles in the present invention and the existing - technology structure.

[0046] Figure 26 Radar graph of the energy - absorption evaluation parameters of six energy - absorbing structures for new - energy vehicles in the present invention and the existing - technology structure. Specific embodiments

[0047] In order to enable those skilled in the art to well understand the technical solution of the present invention, the present invention will be further described below in conjunction with embodiments and drawings. However, the embodiments of the present invention are not limited thereto.

[0048] Embodiment 1

[0049] See Figures 1 - 2 、Figures 6 - 7 and Figures 11 - 12 , this embodiment discloses an energy absorption structure for a new energy vehicle based on a following curve gradient multi-cell self-similar unit 101, which includes a first multi-cell self-similar structure. The first multi-cell self-similar structure includes a gradient multi-cell self-similar unit 101. The gradient multi-cell self-similar unit 101 includes a polygonal tube 1 and a plurality of similar polygonal energy absorption tubes 2 disposed inside the polygonal tube 1 and similar to the polygonal tube 1. The plurality of similar polygonal energy absorption tubes 2 are distributed in a spiral manner along the following curve from the outside to the inside in sequence.

[0050] See Figures 1 - 2 、 Figures 6 - 7 and Figures 11 - 12 , the similarity between the polygonal tube 1 and the similar polygonal energy absorption tube 2 means that they have the same shape but different sizes. Following curve: Each vertex of the polygon makes each vertex follow an adjacent vertex in a certain direction, and at the same time the vertex approaches the midpoint of the polygon. The trajectory left by each vertex is the following curve. Pursuit curve: Describes the trajectory formed when an object (the pursuer) continuously follows another moving object (the target) with a specific strategy. The following curve in this embodiment means that the fixed points of the polygons in each layer are all distributed on this pursuit curve.

[0051] See Figures 1 - 2 、 Figures 6 - 7 and Figures 11 - 12 , the side edge 3 of the outermost similar polygonal energy absorption tube 2 is connected to the inner side surface of the polygonal tube 1; among two adjacent similar polygonal energy absorption tubes 2, the side edge 3 of the inner similar polygonal energy absorption tube 2 is connected to the inner side surface of the outer similar polygonal energy absorption tube 2. In the above structure, the outermost similar polygonal energy absorption tube 2 is connected to the polygonal tube 1, and the adjacent similar polygonal energy absorption tubes 2 are connected to each other, which can improve the strength of the energy absorption structure of the new energy vehicle and can disperse the impact energy to improve the anti-collision effect.

[0052] See Figures 1 - 2 、 Figures 6 - 7 and Figures 11 - 12 , the cross-sectional shapes of the polygonal tube 1 and the similar polygonal energy absorption tube 2 are both polygons, and the polygon is an equilateral polygon; any two polygons are similar polygons; among two adjacent polygons, each vertex of the inner polygon is connected to each side of the outer polygon in a one-to-one correspondence; the vertex is a point on the side edge 3 of the similar polygonal energy absorption tube 2. The purpose is to make the structure more stable by setting the polygonal tube 1 and the similar polygonal energy absorption tube 2 with a polygonal cross-sectional shape, which can improve the strength and energy absorption effect of the energy absorption structure of the new energy vehicle.

[0053] See Figures 1 - 2 、 Figures 6 - 7 andFigures 11 - 12 , in two adjacent polygons, vertex positions 4 are selected at the same ratio on each side of the outer polygon, and the vertex position 4 is the position of the vertex of the inner polygon. In the above structure, the purpose is to make the vertices of the polygon located on the follower curve, and two adjacent polygons are connected to each other. When an external impact acts on the energy absorption structure of the new energy vehicle, each inner polygon will absorb and disperse the impact energy, and the internal hierarchical structure will produce stacking deformation to form wrinkles, so as to reduce the influence of the impact force on the structure.

[0054] See Figures 1 - 2 , the polygon in this embodiment can be a triangle. When the number of triangles is 3, the gradient multi-cell self-similar unit 101 becomes the gradient multi-cell self-similar unit of the 3rd-order triangle follower curve. Specifically, when the number of triangles is n, the gradient multi-cell self-similar unit 101 becomes the gradient multi-cell self-similar unit of the nth-order triangle follower curve.

[0055] See Figures 1 - 2 , Figures 6 - 7 and Figures 11 - 12 , the working principle of the above energy absorption structure of the new energy vehicle is as follows:

[0056] Multiple similar polygon energy absorption tubes 2 are distributed spirally along the follower curve from the outside to the inside in turn, so that multiple similar polygon energy absorption tubes 2 form a hierarchical structure. When the energy absorption structure of the new energy vehicle is subjected to an external impact, the multiple similar polygon energy absorption tubes 2 inside will absorb and disperse the impact energy, and the internal hierarchical structure will produce stacking deformation to form wrinkles, which can quickly absorb energy and reduce the influence of the impact force on the structure.

[0057] Embodiment 2

[0058] See Figures 1 - 15, on the basis of Embodiment 1, both the polygonal tube 1 and the similar polygonal energy-absorbing tube 2 are formed by sequentially connecting multiple side plates end to end in a surrounding manner, and the side plates correspond one by one to the sides of the polygon; the vertex position 4 divides each side of the polygon into two line segments, the longer line segment is the long line segment, and the shorter line segment is the short line segment; the part of the side plate corresponding to the long line segment is the long connecting plate 5, and the part of the side plate corresponding to the short line segment is the short connecting plate 6, that is, the side plate is divided into two parts, the long connecting plate 5 and the short connecting plate 6; the similar polygonal energy-absorbing tubes 2 are arranged from outside to inside. When the number of similar polygonal energy-absorbing tubes 2 is even, the long connecting plates 5 of the similar polygonal energy-absorbing tubes 2 in the odd layers are removed; when the number of similar polygonal energy-absorbing tubes 2 is odd, the long connecting plates 5 of the similar polygonal energy-absorbing tubes 2 in the second-to-last layer and the odd layers before the second-to-last layer are removed. Removing the long connecting plate 5 can be regarded as setting a through groove between the outermost similar polygonal energy-absorbing tube 2 and the polygonal tube 1 and between adjacent similar polygonal energy-absorbing tubes 2, and the through groove removes the long connecting plate 5. In the above structure, part of the long connecting plate 5 is removed and the short connecting plate 6 is retained, and the connection is realized through the short connecting plate 6. The short connecting plate 6 can be regarded as a connecting rib plate. Removing the long connecting plate 5 can increase the gap between the polygonal tube 1 and the similar polygonal energy-absorbing tube 2 and between two similar polygonal energy-absorbing tubes 2, reducing the structural weight while taking into account stability and compressive resistance.

[0059] See Figures 1 - 5 , the polygon is a triangle (equilateral triangle). Both the polygonal tube 1 and the similar polygonal energy-absorbing tube 2 are formed by sequentially connecting three side plates end to end in a surrounding manner. The gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of a triangular following curve. The triangular polygonal tube 1 is called a triangular tube, and the triangular similar polygonal energy-absorbing tube 2 is called a similar triangular energy-absorbing tube; by setting the triangular shape, the structures of the polygonal tube 1 and the similar polygonal energy-absorbing tube 2 are simpler. The wall thickness of the polygonal tube 1 is 0.6 mm, the diameter of the inscribed circle of the triangle of the polygonal tube 1 is 30 mm, and the length (axial length) of the polygonal tube 1 is 50 mm.

[0060] See Figures 1 - 5 , the design method of the energy-absorbing structure of the new energy vehicle includes: the cross-sectional shape of the polygonal tube 1 is a triangle, and based on the triangle, a variety of gradient multi-cell self-similar units 101 of following curves are obtained through transformation by order, ratio, and deletion method. The triangle of the polygonal tube 1 is the first-order triangle, and the triangle of the outermost similar polygonal energy-absorbing tube 2 is the second-order triangle, and the order increases sequentially from outside to inside one by one.

[0061] The three sides of the first-order triangle are simultaneously segmented in the ratios of 1:9, 2:8, or 3:7. The segmentation points are the vertex positions 4. The segmentation points are taken as the vertices of the next-order (second-order) triangle, and then the segmentation points of each side are connected in sequence to form the second-order triangle. The second-order triangle is the cross-sectional shape of the outermost similar polygon energy-absorbing tube 2. The wall thickness of the similar polygon energy-absorbing tube 2 is 0.3 mm. According to this rule, 2nd-order triangular follower curve gradient multi-cell self-similar units with 3 different ratios can be obtained. The vertex position 4 (segmentation point) divides each side of the first-order triangle into two line segments. The longer line segment is the long line segment, and the shorter line segment is the short line segment.

[0062] There are multiple deletion methods. The first deletion method (abbreviated as 1 / 1) is: when the order is odd, the long line segments of the sides of the even-order triangles are deleted. The second deletion method (abbreviated as 1 / 2) is: when the order is even, the long line segments of the sides of the second-to-last order and the even-order triangles before the second-to-last order are deleted.

[0063] Taking the ratio of 3:7 and the order of 3 as an example, each side of the first-order triangle is segmented in the ratio of 3:7. After taking the segmentation points, the segmentation points are connected in sequence to form the third-order triangle. The wall thickness of the similar polygon energy-absorbing tube 2 corresponding to the third-order triangle is 0.3 mm. The first deletion method (abbreviated as 1 / 1) is introduced, and the long line segments (line segments with a length ratio of 7) of the sides of the second-order triangle are deleted, and the short line segments (line segments with a length ratio of 3) are retained; and the first-order triangle and the third-order triangle are retained to form a 2nd-order triangular follower curve gradient multi-cell self-similar unit. That is, the initial total order is 3. After the deletion method, the retained order is 2, forming a 2nd-order triangular follower curve gradient multi-cell self-similar unit. Based on this idea, the 3rd-order triangular follower curve gradient multi-cell self-similar unit is based on a triangle with an order of 5 (odd order). The long line segments (line segments with a length ratio of 7) of the sides of the second-order and fourth-order triangles are deleted, that is, the long line segments of the sides of the even-order triangles are deleted, and the short line segments (line segments with a length ratio of 3) are retained. The short line segments connect the first, third, and fifth-order triangles. By varying the order, ratio, and deletion method, 2nd-order triangular follower curve gradient multi-cell self-similar units with n orders are obtained, where n represents the number of triangles retained after the deletion method.

[0064] Taking the ratio of 3:7 and the order of 6 as an example, a second deletion method (abbreviated as 1 / 2) is introduced. Based on a triangle of order 6 (even order), the long line segments (line segments with a length ratio of 7) of each side of the second-order, fourth-order, and fifth-order triangles are deleted, that is, the long line segments of each side of the second-to-last order and the even-order triangles before the second-to-last order are deleted. The second-to-last order is the fifth order, and the second order and the fourth order belong to the even-order triangles before the fifth order. The short line segments (line segments with a length ratio of 3) are retained; the short line segments connect the first-order, third-order, and sixth-order triangles to form another gradient multi-cell self-similar unit of a 3-order triangle following curve.

[0065] The ratio of this embodiment is 1:9 or 2:8 or 3:7. As needed, other ratios can be set, and there are many deletion methods, and other deletion methods can be selected according to the energy absorption requirements.

[0066] Embodiment 3

[0067] See Figures 6 - 7 , other structures in this embodiment are the same as those in Embodiment 1. The difference is that the polygon in this embodiment can be a quadrilateral. When the number of quadrilaterals is 3, the gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of a 3-order quadrilateral following curve. When the number of quadrilaterals is n, the gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of an n-order quadrilateral following curve.

[0068] Embodiment 4

[0069] See Figures 6 - 10 , other structures in this embodiment are the same as those in Embodiment 2. The difference is that the polygon is a quadrilateral (equilateral quadrilateral). The polygon tube 1 and the similar polygon energy absorption tube 2 are both formed by four side plates connected end to end in sequence. The design method of the energy absorption structure of the new energy vehicle is the same as that of Embodiment 2, except that the matrix is a quadrilateral. The gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of a quadrilateral following curve; the polygon tube 1 of the quadrilateral is called a quadrilateral tube, and the similar polygon energy absorption tube 2 of the quadrilateral is called a similar quadrilateral energy absorption tube; the energy absorption effect of the polygon tube 1 of the quadrilateral and the similar polygon energy absorption tube 2 is better than that of the triangle in Embodiment 2. At the same order, the internal space of the gradient multi-cell self-similar unit of the quadrilateral following curve is larger. During the collision process, the hierarchical structures interact with each other to produce stacking deformation, and the number of folds generated becomes more and more uniform, the energy absorption ability is improved, and at the same time, the initial peak force is reduced.

[0070] Taking the ratio of 3:7 and the order of 3 as an example, the first deletion method is introduced. The long line segments (line segments with a length ratio of 7) of each side of the second-order quadrilateral are deleted, and the short line segments (line segments with a length ratio of 3) are retained; and the first-order quadrilateral and the third-order quadrilateral are retained to form a gradient multi-cell self-similar unit of a 2-order quadrilateral following curve.

[0071] See Figures 8 - 9 , taking the ratio of 3:7 and the order of 6 as an example, the second deletion method is introduced. The first-order quadrilateral, the third-order quadrilateral and the sixth-order quadrilateral are retained to form a gradient multi-cell self-similar unit of a 3-order quadrilateral following curve.

[0072] Among them, the length of the gradient multi-cell self-similar unit 101 in this embodiment is 50 mm, the diameter of the inscribed circle of the first-order quadrilateral is 30 mm, the wall thickness of the polygon tube 1 corresponding to the first-order quadrilateral is 0.6 mm, and the wall thickness of the similar polygon energy-absorbing tube 2 corresponding to the second-order and above quadrilaterals is 0.3 mm. The gradient multi-cell self-similar unit of the quadrilateral following curve in this embodiment can also be set to other sizes to meet the requirements.

[0073] Embodiment 5

[0074] See Figures 11 - 12 , the other structures in this embodiment are the same as those in Embodiment 1. The difference is that the polygon in this embodiment can be a hexagon. When the number of hexagons is 3, the gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of a 3-order hexagon following curve. Specifically, when the number of hexagons is n, the gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of an n-order hexagon following curve.

[0075] Embodiment 6

[0076] See Figures 13 - 15, the other structures in this embodiment are the same as those in Embodiment 2. The difference is that the polygon is a hexagon (equilateral hexagon). The polygon tube 1 and the similar polygon energy-absorbing tube 2 are both formed by enclosing six side plates connected end to end in sequence. The design method of the energy-absorbing structure of the new energy vehicle is the same as that in Embodiment 2. The difference is that the matrix is a hexagon. The gradient multi-cell self-similar unit 101 becomes a gradient multi-cell self-similar unit of a hexagonal following curve; the energy-absorbing effect of the hexagonal polygon tube 1 and the similar polygon energy-absorbing tube 2 is better than that of the quadrilateral in Embodiment 4. Adjacent hexagons are in contact and connected, and the connection stability is good, thus improving the overall structural rigidity. When the energy-absorbing structure of the new energy vehicle is subjected to a certain impact force, more wrinkles are generated at the contact points of adjacent hexagons. Secondly, the external impact force will be transmitted through the contact ends of adjacent hexagons. After the gap between each layer is buffered and transitioned, the impact force is effectively reduced, thereby reducing the impact on the energy-absorbing structure of the new energy vehicle and making it have good anti-impact ability and buffering ability, which is beneficial to reducing the damage caused by the impact.

[0077] Taking the ratio of 3:7 and the order of 3 as an example, the first deletion method is introduced. The long line segments (line segments with a length ratio of 7) of each side of the second-order hexagon are deleted, and the short line segments (line segments with a length ratio of 3) are retained; and the first-order hexagon and the third-order hexagon are retained to form a gradient multi-cell self-similar unit of a 2-order hexagonal following curve.

[0078] See Figures 13 - 14 , taking the ratio of 3:7 and the order of 6 as an example, the second deletion method is introduced. The first-order hexagon, the third-order hexagon, and the sixth-order hexagon are retained to form a gradient multi-cell self-similar unit of a 3-order hexagonal following curve.

[0079] Among them, the length of the gradient multi-cell self-similar unit 101 in this embodiment is 50 mm, the inscribed circle diameter of the first-order hexagon is 30 mm, the wall thickness of the polygon tube 1 corresponding to the first-order hexagon is 0.6 mm, and the wall thickness of the similar polygon energy-absorbing tube 2 corresponding to the second-order and above hexagons is 0.3 mm. The gradient multi-cell self-similar unit of the quadrilateral following curve in this embodiment can also be set to other sizes to meet the requirements.

[0080] Embodiment 7

[0081] See Figures 16 - 20 , the other structures in this embodiment are the same as those in Embodiment 1. The polygon is also a triangle (equilateral triangle). The difference is that the gradient multi-cell self-similar unit of the triangular following curve is self-combined, and is arrayed along the circumferential direction or mirror-combined with the side edge of the polygon tube 1 as the center. The number of the gradient multi-cell self-similar units 101 is 6.

[0082] See Figures 16 - 18, specifically, the circumferential array mode is as follows: 6 gradient multi-cell self-similar units 101 are arrayed along the circumferential direction, and the outer sides of the polygon tubes 1 of two adjacent gradient multi-cell self-similar units 101 are connected to each other. A circular array is performed with the side edges of the polygon tubes 1 in the gradient multi-cell self-similar unit 101 as the center. In the above structure, the polygon tubes 1 of the 6 gradient multi-cell self-similar units 101 are integrally arranged, so that the outer shape of the entire energy absorption structure of the new energy vehicle becomes a hexagonal prism shape. The outer sides of two adjacent polygon tubes 1 are connected to each other, making the overall structure more compact, which is beneficial to improving the rigidity of the overall structure. During the deformation process, the structures at all levels interact with each other, increasing the number of folds generated during the deformation process, making the fold wavelength shorter and more uniform. During the collision stage, the fluctuation of the impact force is smaller, the energy absorption is greatly improved, and the collision is more stable.

[0083] See Figures 16 - 20 , in this embodiment, a single gradient multi-cell self-similar unit 101 is a gradient multi-cell self-similar unit of a 5th-order triangular follower curve, and the number of the similar polygon energy absorption tubes 2 is 4, that is, the cross-sectional shape of a single gradient multi-cell self-similar unit 101 has a total of 5 triangles from the outside to the inside. The length of the single gradient multi-cell self-similar unit 101 is 50 mm, that is, the side edge length is 50 mm. The inscribed circle diameter of the first-order triangle is 10 mm, the wall thickness of one side of the polygon tube 1 corresponding to the first-order triangle is 0.6 mm, and the wall thicknesses of the other two sides are 0.3 mm. The wall thicknesses of the second, third, fourth, and fifth-order triangles are all 0.3 mm. With the side edges connected by the wall thicknesses of 0.3 mm on both sides of the first-order triangle as the center, 6 gradient multi-cell self-similar units 101 are circularly arrayed, so that the 6 gradient multi-cell self-similar units 101 are arrayed and combined to form a gradient multi-cell self-similar circular array combination structure of a triangular follower curve, that is, the first multi-cell self-similar structure. The outermost layer of the first multi-cell self-similar structure forms a hexagonal shape, and the inscribed circle diameter of the outermost hexagon is 30 mm.

[0084] See Figure 16 and Figures 19 - 20, the way of mirror combination is as follows: six gradient multi-cell self-similar units 101 are divided into two pairs. Each pair of gradient multi-cell self-similar units 101 is symmetrically distributed with the side edge of the polygonal tube 1 as the center, and the outer side surfaces of the polygonal tubes 1 of two adjacent gradient multi-cell self-similar units 101 are connected to each other. The length of the single gradient multi-cell self-similar unit 101 is 50 mm, that is, the length of the side edge is 50 mm. The diameter of the inscribed circle of the first-order triangle is 10 mm. The wall thickness of one side of the polygonal tube 1 corresponding to the first-order triangle is 0.6 mm, and the wall thicknesses of the other two sides are 0.3 mm. The wall thicknesses of the second, third, fourth, and fifth-order triangles are all 0.3 mm. Taking the side edge connected by the wall thicknesses of 0.3 mm on both sides of the first-order triangle as the center for mirroring, three pairs of gradient multi-cell self-similar units 101 are each mirror-combined. That is, six gradient multi-cell self-similar units 101 are divided into three pairs, and each pair is symmetrically arranged, so that the six gradient multi-cell self-similar units 101 are array-combined to form a gradient multi-cell self-similar mirror-symmetric combined structure following a triangular curve, that is, the first multi-cell self-similar structure. The outermost layer of the first multi-cell self-similar structure forms a hexagonal shape, and the diameter of the inscribed circle of the outermost hexagon is 30 mm. The outer side surfaces of adjacent polygonal tubes 1 are connected to each other, making the overall structure more compact, which is beneficial to improving the rigidity of the overall structure. During the deformation process, the structures at all levels interact with each other, increasing the number of folds generated during the deformation process, making the fold wavelength shorter and more uniform. During the collision stage, the fluctuation of the impact force is smaller, the energy absorption is greatly improved, and the collision is more stable.

[0085] Example 8

[0086] See Figure 21 , the energy absorption structure of the new energy vehicle in this embodiment further includes a second multi-cell self-similar structure 200, and the second multi-cell self-similar structure 200 is connected in series with the first multi-cell self-similar structure 100; wherein, the first multi-cell self-similar structure 100 is the first multi-cell self-similar structure of Example 7. The second multi-cell self-similar structure 200 and the first multi-cell self-similar structure 100 are connected in series to form a gradient multi-cell self-similar series structure following a series curve.

[0087] See Figure 21, specifically, the second multi-cell self-similar structure 200 includes a gradient multi-cell self-similar unit 101. The other structures of the gradient multi-cell self-similar unit 101 of the second multi-cell self-similar structure 200 are the same as those of the gradient multi-cell self-similar unit 101 of the first multi-cell self-similar structure 100. The difference is that the polygon of the gradient multi-cell self-similar unit 101 of the second multi-cell self-similar structure is a hexagon, while the polygon of the gradient multi-cell self-similar unit 101 of the first multi-cell self-similar structure is a triangle. Specifically, the second multi-cell self-similar structure is the first multi-cell self-similar structure in Embodiment 6. In the above structure, the first multi-cell self-similar structure 100 formed by arranging 6 gradient multi-cell self-similar units 101 along the circumferential direction is combined with the hexagonal second multi-cell self-similar structure 200 to form a whole, obtaining a gradient multi-cell self-similar series structure of a serial following curve, effectively reducing the weight of the structure, making the structure lighter, and also ensuring the rigidity of the overall structure. During the collision stage, the fluctuation of the impact force is smaller, the energy absorption is greatly improved, and the collision is more stable.

[0088] The overall length of the energy absorption structure of the new energy vehicle in this embodiment is 50 mm, the length of the first multi-cell self-similar structure 100 is 30 mm, the diameter of the circumscribed circle of the first-order triangle is 10 mm, and the wall thickness corresponding to the first-order triangle is 0.6 mm. The order of the first multi-cell self-similar structure is 5, and the wall thicknesses corresponding to the second, third, fourth, and fifth-order triangles are 0.3 mm. The length of the second multi-cell self-similar structure 200 is 20 mm; the gradient multi-cell self-similar unit of the second multi-cell self-similar structure 200 is a gradient multi-cell self-similar unit of a 5th-order hexagonal following curve. The diameter of the circumscribed circle of the first-order hexagon is 30 mm, the corresponding wall thickness is 0.6 mm, and the ratio is 2:8. The wall thicknesses of the remaining hexagons are 0.3 mm.

[0089] See Figures 22 - 23 , perform axial simulation impact tests on the gradient multi-cell self-similar units of 3rd-order triangles, quadrilaterals, and hexagons with a ratio of 2:8 and no introduced deletion method of order 3, the gradient multi-cell self-similar units of 3rd-order triangle following curves with a ratio of 3:7 and the introduction of the second deletion method (abbreviated as 1 / 2) of order 5, the gradient multi-cell self-similar mirror-symmetric combination structure of triangle following curves, the gradient multi-cell self-similar series structure of serial following curves, and the hexagonal single tube in the prior art, and obtain the energy absorption curve, force-displacement curve, and crashworthiness performance data. Figure 22 , Figure 23 , Figure 25 and Figure 26Among them, the triangle represents a gradient multi-cell self-similar unit of a 3rd-order triangle following curve with a ratio of 2:8 and no introduced deletion order of 3. The quadrilateral represents a gradient multi-cell self-similar unit of a 3rd-order quadrilateral following curve with a ratio of 2:8 and no introduced deletion order of 3. The hexagon represents a gradient multi-cell self-similar unit of a 3rd-order hexagon following curve with a ratio of 2:8 and no introduced deletion order of 3. The triangle 1 / 2 represents a gradient multi-cell self-similar unit of a 3rd-order triangle following curve with a ratio of 3:7 and the introduction of the second deletion method (abbreviated as 1 / 2) with an order of 5. The hexagon single tube represents the hexagon single tube in the prior art. The triangular symmetric combination represents the gradient multi-cell self-similar mirror symmetric combination structure of the triangle following curve. The triangular combined with hexagonal gradient combination represents the gradient multi-cell self-similar series structure of the following curves in series in Example 8.

[0090] From Figure 22 's energy absorption curve, it can be seen that the gradient multi-cell self-similar mirror symmetric combination structure of the triangle following curve is superior to the gradient multi-cell self-similar series structure of the following curves in series. The energy absorption effects of these two structures increase significantly, and the energy absorption efficiency continues to rise. Both are 3 times more energy-absorbing than the gradient multi-cell self-similar units of the triangle, quadrilateral, and hexagon following curves. From Figure 22 's force-displacement curve, it can be seen that all seven structures reach the peak force rapidly in the initial stage of the impact, and then enter the relatively stable stage. The gradient multi-cell self-similar mirror symmetric combination structure of the triangle following curve and the gradient multi-cell self-similar series structure of the following curves in series finally enter the densification stage and the impact force rises rapidly. It can be seen from the figure that the force-displacement curves of the seven structures fluctuate smoothly. In the collision stage, the smaller the fluctuation of the impact force, the more stable the collision, and it is more conducive to protecting the integrity of the structure.

[0091] See Figures 24 - 25 , EA represents energy absorption, SEA represents specific energy absorption, IPCF represents initial peak force, MCF represents average impact load, and CFE represents load efficiency. From Figure 25 and Figure 26 it can be seen that among the gradient multi-cell self-similar units of the 3rd-order triangle following curve, the energy absorption of the gradient multi-cell self-similar unit of the triangle following curve with the second deletion method (abbreviated as 1 / 2) is similar to that of the gradient multi-cell self-similar unit of the triangle following curve without deletion. However, due to the lighter mass of the gradient multi-cell self-similar unit of the triangle following curve with the second deletion method (abbreviated as 1 / 2), the specific energy absorption is increased by 14.85%, realizing the lightweight of the structure. The initial peak force drops by 15.2 kN, making the impact force received by the structure smaller in the collision stage, which is more conducive to protecting the integrity of the structure. The load efficiency is increased by 4%. It can be seen from Figure 24From the wrinkling deformation process diagram, it can be seen that the gradient multi-cellular self-similar unit of the triangular following curve with the second deletion method (abbreviated as 1 / 2) forms more wrinkles and has a shorter wavelength, indicating that the energy absorption efficiency is improved in this process. Therefore, the energy absorption effect of the gradient multi-cellular self-similar structure of the triangular following curve with the second deletion method is better than that of the gradient multi-cellular self-similar unit of the triangular following curve without deletion method.

[0092] Among different polygons with the same order (gradient multi-cellular self-similar units of the same-order polygon following curve) and the same ratio, the energy absorption of the hexagon is more than that of the triangle and the quadrilateral. And when the diameter of the inscribed circle of the first-order polygon is 30mm, the mass of the hexagon is lighter than that of the triangle and the quadrilateral. The initial peak force is 23.37kN lower than that of the triangle. As a result, the specific energy absorption of the hexagon is 22.65J / g, which is 10.33J / g and 4.18J / g larger than that of the triangle and the quadrilateral respectively. The load efficiency of the hexagon is 0.44, which is 0.2 and 0.05 higher than that of the triangle and the quadrilateral. This shows that in the case of a single polygon, with the same order and the same ratio, the gradient multi-cellular self-similar unit of the hexagon following curve has better energy absorption performance. The energy absorptions of the triangular symmetric combination (gradient multi-cellular self-similar mirror symmetric combination structure of the triangular following curve) and the triangular combined with hexagon gradient combination (gradient multi-cellular self-similar series structure of the series following curve) are 3124.63J and 3155.38J respectively. The energy absorption of the triangular combined with hexagon gradient combination is 345.4% higher than that of the triangle and 224% higher than that of the hexagon. The initial peak force of the triangular combined with hexagon gradient combination is 138.98kN, which is 15.58kN lower than that of the triangular symmetric combination. Since the mass of the triangular combined with hexagon gradient combination is smaller than that of the triangular symmetric combination, the specific energy absorption of the triangular combined with hexagon gradient combination is 35.69J / g, which is 6.41J / g higher than that of the triangular symmetric combination. It can be seen from this that the gradient multi-cellular self-similar series structure of the series following curve has better energy absorption performance than the gradient multi-cellular self-similar mirror symmetric combination structure of the triangular following curve.

[0093] See Figures 22 - 26 , in addition, in the automotive field, the energy absorption boxes of existing automobiles usually adopt thin-walled structures (square / circular / hexagonal), which have simple processes and low costs, but their energy absorption efficiency is relatively limited. For the existing thin-walled structures, such as the hexagonal single tube, the dimensions of the hexagonal single tube are: the structural length is 50mm, the diameter of the inscribed circle is 30mm, and the wall thickness is 0.6mm. Through Figure 25It can be seen that the gradient multi-cell self-similar mirror-symmetric composite structure following the triangular curve has an energy absorption 706.05% higher than that of the hexagonal single tube in the prior art, a specific energy absorption (SEA) 118.82% higher, a load efficiency 130.3% higher, and an initial peak force 104.07 kN higher than that of the hexagonal single tube, indicating that the gradient multi-cell self-similar mirror-symmetric composite structure following the triangular curve has better rigidity. In addition, the gradient multi-cell self-similar unit following the hexagonal curve has an energy absorption 148.81% higher than that of the hexagonal single tube, a specific energy absorption 38.87% higher, a load efficiency 33.33% higher, and an initial peak force 28.55 kN higher than that of the hexagonal single tube, indicating that the gradient multi-cell self-similar unit following the hexagonal curve has better rigidity than the hexagonal single tube. According to Figure 24 It can be seen that during axial compression, the hexagonal single tube forms fewer wrinkles, shorter wavelengths, absorbs less energy, and has the slowest growth rate of energy absorption effect. The gradient multi-cell self-similar unit following the hexagonal curve and the gradient multi-cell self-similar series structure of the series-connected following curves have denser wrinkles, shorter average wrinkle wavelengths, and more energy absorption, with a better energy absorption effect.

[0094] The above is a preferred embodiment of the present invention, but the embodiments of the present invention are not limited to the above content. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. An energy-absorbing structure for a new energy vehicle based on a multi-cell self-similar unit with a following curve gradient, characterized in that It includes a first multi-cell self-similar structure, and the first multi-cell self-similar structure includes gradient multi-cell self-similar units. The gradient multi-cell self-similar unit includes a polygonal tube and a plurality of similar polygonal energy-absorbing tubes arranged inside the polygonal tube and similar to the polygonal tube. The plurality of similar polygonal energy-absorbing tubes are distributed in a spiral manner along a following curve from the outside to the inside in sequence.

2. The energy-absorbing structure of the new energy vehicle according to claim 1, wherein The side edges of the outermost similar polygonal energy-absorbing tube are connected to the inner side surface of the polygonal tube; among two adjacent similar polygonal energy-absorbing tubes, the side edges of the inner similar polygonal energy-absorbing tube are connected to the inner side surface of the outer similar polygonal energy-absorbing tube.

3. The energy absorption structure of the new energy vehicle according to claim 2, characterized in that, The cross-sectional shapes of the polygonal tube and the similar polygonal energy-absorbing tubes are both polygons; any two polygons are similar polygons; among two adjacent polygons, each vertex of the inner polygon is connected to each side of the outer polygon in a one-to-one correspondence; the vertex is a point on the side edge of the similar polygonal energy-absorbing tube.

4. The energy absorption structure of the new energy vehicle according to claim 3, characterized in that, Among two adjacent polygons, the vertex positions are selected at the same ratio on each side of the outer polygon, and the vertex positions are the positions of the vertices of the inner polygon.

5. The energy absorber structure of the new energy vehicle according to claim 4, characterized in that Both the polygonal tube and the similar polygonal energy-absorbing tubes are formed by sequentially connecting a plurality of side plates end to end, and the side plates correspond to the sides of the polygon one by one; the vertex positions divide each side of the polygon into two line segments, the longer line segment is the long line segment, and the shorter line segment is the short line segment; the part of the side plate corresponding to the long line segment is the long connecting plate, and the part of the side plate corresponding to the short line segment is the short connecting plate; the similar polygonal energy-absorbing tubes are arranged from the outside to the inside. When the number of similar polygonal energy-absorbing tubes is even, the long connecting plates of the odd-layer similar polygonal energy-absorbing tubes are removed; when the number of similar polygonal energy-absorbing tubes is odd, the long connecting plates of the similar polygonal energy-absorbing tubes of the second-to-last layer and the odd layers before the second-to-last layer are removed.

6. The energy absorption structure of the new energy vehicle according to any one of claims 1-5, characterized in that, The polygon is a triangle.

7. The energy absorption structure of a new energy vehicle according to any one of claims 1-5, characterized in that, The polygon is a quadrilateral.

8. The energy absorption structure of a new energy vehicle according to any one of claims 1-5, characterized in that The polygon is a hexagon.

9. The energy-absorbing structure of the new energy vehicle according to claim 6, characterized in that, The number of the gradient multi-cell self-similar units is 6; the 6 gradient multi-cell self-similar units are arrayed along the circumferential direction or mirror-combined with the side edge of the polygonal tube as the center, and the outer side surfaces of the polygonal tubes of two adjacent gradient multi-cell self-similar units are connected to each other.

10. The energy-absorbing structure of a new energy vehicle according to claim 9, wherein, The energy-absorbing structure of the new energy vehicle further includes a second multi-cell self-similar structure, and the second multi-cell self-similar structure is connected in series with the first multi-cell self-similar structure; wherein, the second multi-cell self-similar structure includes one gradient multi-cell self-similar unit, and the other structures of the gradient multi-cell self-similar unit of the second multi-cell self-similar structure are the same as those of the gradient multi-cell self-similar unit of the first multi-cell self-similar structure. The difference is that the polygon of the gradient multi-cell self-similar unit of the second multi-cell self-similar structure is a hexagon.

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