Double-elliptical annular negative Poisson's ratio buffering and energy absorbing structure

Abstract

The utility model discloses a double elliptical annular negative Poisson's ratio buffer energy absorption structure, which is characterized in that a unit cell unit array is arranged on a bottom plate, two concave hexagonal frames in each unit cell unit are laterally symmetrical concave hexagons, the two concave hexagonal frames are arranged in a mutually crossed manner to form an outer frame of the unit cell unit, and the outer frame of the unit cell unit is provided with a concave hexagonal frame. The two elliptical rings are arranged in an outer frame formed by the two concave hexagonal frames, and the two elliptical rings are tangent to each other. According to the buffering and energy absorbing structure, the inner oval annular structure is additionally arranged on the basis of a traditional inwards-concave hexagon, the advantages of the traditional inwards-concave hexagon are considered, meanwhile, the inner support of the negative Poisson's ratio buffering structure is additionally arranged, the buffering performance of the whole structure is enhanced, and when the buffering and energy absorbing structure is impacted by loads, the buffering effect is good. The inward-concave hexagonal structure contracts inwards under stress, an obvious negative Poisson's ratio effect is generated, and higher load impact and more energy absorption can be borne.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the buffer energy-absorbing super material field, concretely relates to a double ellipse annular negative poisson's ratio buffer energy-absorbing structure. BACKGROUND

[0002] The negative poisson's ratio super material is a novel super material with unique deformation behavior, and the difference between the negative poisson's ratio super material and traditional material is that the negative poisson's ratio super material shrinks in another direction perpendicular to the pressure when being pressed in a certain direction, and this deformation behavior is called negative poisson's ratio effect. Due to the negative poisson's ratio effect, the negative poisson's ratio super material shrinks to the impacted part when being impacted, and the local structure density of the impacted part is enhanced, so that the structure has excellent properties such as high energy absorption, indentation resistance, strong fracture toughness and the like.

[0003] The traditional concave negative poisson's ratio structure has single deformation mode, and is prone to large platform stress fluctuation, stress concentration and insufficient protection support force in the face of extreme impact load, so the protection function needs to be improved. SUMMARY

[0004] In order to solve the above technical defects in the prior art, the utility model provides a kind of.

[0005] The technical solution for achieving the purpose of the utility model is as follows:

[0006] A double ellipse annular negative poisson's ratio buffer energy-absorbing structure includes a bottom plate and a unit cell;

[0007] The unit cell array is arranged on the bottom plate, and the unit cell and the bottom plate are integrally formed.

[0008] Further, the unit cell includes a concave hexagonal frame and an elliptical ring.

[0009] The concave hexagonal frame is a laterally symmetrical concave hexagon, and there are two concave hexagonal frames, which are arranged intersecting each other to form an outer frame of the unit cell.

[0010] The elliptical ring has two, and the two elliptical rings are arranged in the outer frame formed by the two concave hexagonal frames, and are arranged tangentially between the two elliptical rings.

[0011] Further, the minor axis of the elliptical ring is in the vertical direction.

[0012] Further, the inward bending angle of the concave hexagonal frame is 60°

[0013] Further, the bottom edge of the concave hexagonal frame is arranged parallel to the bottom plate.

[0014] Further, the concave hexagonal frame and the elliptical ring are both center-symmetrical structures.

[0015] Further, the cell unit array is arranged on the bottom plate, and is provided with multiple rows and multiple columns.

[0016] Further, the bottom plate, the inner recessed hexagonal frame and the elliptical ring are all made of TPU flexible material.

[0017] Compared with the prior art, the utility model has the advantages that:

[0018] The cell unit of the scheme increases the internal elliptical ring structure on the basis of the traditional inner recessed hexagon, not only takes into account the advantages of the traditional inner recessed hexagon, but also increases the internal support of the negative Poisson's ratio buffer structure, enhances the buffer performance of the overall structure, when the structure is subjected to load impact, the inner recessed hexagonal structure is inwards contracted under stress, and obvious negative Poisson's ratio effect is generated.

[0019] The scheme absorbs the axial impact load energy through the double-elliptical ring negative Poisson's ratio structure, prevents the harm of external impact to the human body.

[0020] The utility model will be described in further detail below in combination with the drawings and specific embodiments. DRAWINGS

[0021] Figure 1 It is a perspective view of the double-elliptical ring negative Poisson's ratio buffer energy-absorbing structure of the utility model.

[0022] Figure 2 It is a front view of the double-elliptical ring negative Poisson's ratio buffer energy-absorbing structure of the utility model.

[0023] Figure 3 It is a plan view of the double-elliptical ring negative Poisson's ratio buffer energy-absorbing structure of the utility model.

[0024] Figure 4 It is a schematic view of the double-elliptical ring negative Poisson's ratio buffer energy-absorbing structure of the utility model.

[0025] Figure 5 It is a sectional view of the double-elliptical ring negative Poisson's ratio buffer energy-absorbing structure of the utility model.

[0026] Figure 6 It is an application schematic view of the double-elliptical ring negative Poisson's ratio buffer energy-absorbing structure in the embodiment of the utility model.

[0027] Figure 7The stress-strain curve diagram of the double-elliptical annular negative Poisson's ratio buffer energy absorption structure in the embodiment of the utility model is applied. DETAILED DESCRIPTION

[0028] It is easy to understand that, according to the technical scheme of the utility model, a person skilled in the art can imagine various embodiments of the utility model without changing the essential spirit of the utility model. Therefore, the following specific embodiments and drawings are only exemplary descriptions of the technical scheme of the utility model, and should not be regarded as the whole or as a limitation or restriction on the technical scheme of the utility model. On the contrary, the purpose of providing these embodiments is to enable a person skilled in the art to more thoroughly understand the utility model. The preferred embodiments of the utility model are described in detail below in conjunction with the drawings, wherein the drawings form part of the present application and are used together with the embodiments of the utility model to explain the innovative concept of the present application.

[0029] EMBODIMENT

[0030] In combination Figure 1 A double-elliptical annular negative Poisson's ratio buffer energy absorption structure, comprising a bottom plate 1 and a plurality of unit cells;

[0031] The array of unit cells is arranged on the bottom plate 1, and the unit cells and the bottom plate 1 are integrally formed. The bottom plate 1 is a square aperture array structure for fixing the unit cells, facilitating the realization of the 3D printing process. On the one hand, it is convenient to connect to other carriers after being made;

[0032] The unit cells are arranged in an array on the bottom plate 1 and are provided with multiple rows and multiple columns.

[0033] The unit cell comprises an inner recessed hexagonal frame 2 and an elliptical ring 3.

[0034] The inner recessed hexagonal frame 2 is a laterally symmetrical inner recessed hexagon, and there are two inner recessed hexagonal frames 2, which are arranged intersecting each other to form an outer frame of the unit cell.

[0035] The elliptical ring 3 has two, and the two elliptical rings 3 are the same in shape and size, arranged in the outer frame formed by the two inner recessed hexagonal frames 2, and the two elliptical rings 3 are arranged tangentially between them. The elliptical ring 3 has an elliptical short axis in the vertical direction.

[0036] The bottom edge of the inner recessed hexagonal frame 2 is arranged parallel to the bottom plate 1.

[0037] More specifically, the concave hexagonal frame 2 and the elliptical ring 3 are both centrally symmetrical structures. The concave hexagonal frame 2 and the elliptical ring 3 are arranged in two rows vertically and in multiple rows symmetrically arranged in all directions. The concave hexagonal frame 2 is ∑-shaped laterally. Two concave hexagons 2 intersect in a cross shape. Every two elliptical rings 3 form a group of intersections. The two groups are connected vertically at the center of the two concave hexagons.

[0038] In this embodiment, the inward bending angle 4 of the concave hexagonal frame 2 is 60°, and the entire unit cell can be considered as two sets of concave hexagons 2 and four sets of elliptical rings 3 intersecting and connecting. Figure 1 , Figure 2 , Figure 3 As shown, the structure in this embodiment is composed of a 4×4×2 cell array, with dimensions of 40mm×40mm×15mm.

[0039] In addition, the base plate 1, the concave hexagonal frame 2, and the elliptical ring 3 are all made of TPU flexible material.

[0040] In implementing this invention, the buffer energy-absorbing structure array is arranged to the required size and placed perpendicular to the impact location, such as... Figure 6 As shown, a double-elliptical annular negative Poisson's ratio buffer energy-absorbing structure is placed in a universal testing machine apparatus, which includes a pressure sensor 5 and a fixing plate 6. The double-elliptical annular negative Poisson's ratio buffer energy-absorbing structure is placed between the pressure sensor 5 and the fixing plate 6 and is firmly fixed by the fixing plate 6. When subjected to external impact loads, the cellular structure can absorb a large amount of impact energy generated by external collisions through its own deformation. It has the characteristics of high energy absorption and deformation stability, which can effectively prevent external impacts from harming the human body. Moreover, it is printed using TPU flexible material fused deposition modeling technology, which is inexpensive and makes it an excellent buffer energy-absorbing structure.

[0041] The structure is composed of a 4×4×2 unit cell array, with dimensions of 40mm×40mm×15mm. It employs a displacement loading method, with a compression rate of 12mm / min and a maximum deformation of 65%. The stress-strain curve is shown below. Figure 7 As shown, the deformation of the buffer energy-absorbing structure can be divided into three stages: the elastic stage, the plateau stage, and the densification stage. The energy absorption per unit mass is 0.24 J, which is six times that of the traditional concave hexagon.

[0042] In summary, the structure proposed in this design can absorb the impact energy generated by external collisions through its own deformation when subjected to load impacts. It has the characteristics of high energy absorption and stable deformation, which can effectively prevent external impacts from harming the human body. Furthermore, it is printed using fused deposition modeling technology, which is cost-effective and makes it a good buffer energy absorption structure.

[0043] The above examples show and describe the basic principles and main features of the present application. Those skilled in the art should understand that the present application is not limited to the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed application.

Claims

1. A dual-elliptical ring-shaped negative Poisson's ratio cushion energy-absorbing structure, characterized in that, The crystal cell unit array is arranged on the bottom plate (1), and the crystal cell unit and the bottom plate (1) are integrally formed. The crystal cell unit comprises an inner recessed hexagonal frame (2) and an elliptical ring (3). The inner recessed hexagonal frame (2) is a laterally symmetrical inner recessed hexagon, and there are two inner recessed hexagonal frames (2) which are arranged in a cross manner to form an outer frame of the crystal cell unit. There are two elliptical rings (3) which are arranged in a tangent manner between the two elliptical rings (3) in the outer frame formed by the two inner recessed hexagonal frames (2). The elliptic short axis of the elliptical ring (3) is in the vertical direction.

2. Double-elliptical toroidal negative Poisson's ratio energy absorbing structure according to claim 1, characterized in that, The inner bending angle (4) of the inner recessed hexagonal frame (2) is 60°.

3. The bi-elliptical ring-shaped negative Poisson's ratio cushion energy absorbing structure according to claim 1, wherein, The bottom edge of the inner recessed hexagonal frame (2) is arranged in parallel with the bottom plate (1).

4. The bi-elliptical ring-shaped negative Poisson's ratio cushion energy absorbing structure of claim 1, wherein, The inner recessed hexagonal frame (2) and the elliptical ring (3) are both center-symmetrical structures.

5. The bi-elliptical ring-shaped negative Poisson's ratio cushion energy absorbing structure of claim 1, wherein, The crystal cell unit array is arranged on the bottom plate (1) and is arranged in multiple rows and multiple columns.

6. Double-elliptical toroidal negative Poisson's ratio cushion and energy absorbing structure according to any one of claims 1 to 5, characterized in that, The bottom plate (1), the inner recessed hexagonal frame (2) and the elliptical ring (3) are all made of TPU flexible material.

7. The bi-elliptical ring-shaped negative Poisson's ratio cushion and energy absorbing structure of claim 1, wherein, ​

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