Double arrow assembled honeycomb structure

Abstract

The invention discloses a double-arrow assembled honeycomb structure, which relates to the field of layered honeycomb structures, including a first connecting plate, a negative Poisson's ratio sandwich layer and a second connecting plate, wherein the negative Poisson's ratio sandwich layer is located between the first connecting plate and the second connecting plate, and the negative Poisson's ratio sandwich layer includes a plurality of double-arrow assembly structures, wherein the double-arrow assembly structure includes a long folding plate and a short folding plate that are detachably connected; the long folding plate includes a plurality of long arrow units that are connected in sequence, and the short folding plate includes a plurality of short arrow units that are connected in sequence, and the long arrow units and the short arrow units in the double-arrow assembly structure correspond to each other one by one; the long arrow unit includes two long plates that are connected at one end, and the two long plates are both provided with a second slot that is open at the side of the long plate; the short arrow unit includes two short plates that are connected at one end, and the two short plates are both provided with a third slot that is open at the side of the short plate. The invention can realize self-locking in a two-dimensional impact process, and has strong economy and applicability.

Description

Technical Field

[0001] The invention relates to the field of layered honeycomb structures, in particular to a double-arrow assembled honeycomb structure. Background Art

[0002] In recent years, due to social development and scientific and technological progress, the performance requirements of materials / structures used in actual production processes in many fields have also increased. Developing high-performance, lightweight new structures has become one of the powerful means to explore new functions of materials, lead new directions for industries, improve the comprehensive performance of materials, and break through the bottleneck of scarce resources.

[0003] Due to the negative Poisson's ratio effect, the auxetic honeycomb structure has many unique mechanical properties, such as good load-bearing performance, extraordinary elastic constants, and superior impact resistance, energy absorption performance, fracture toughness and fatigue resistance, etc. The superior mechanical properties make it have broad application prospects in many engineering fields, and therefore attracted extensive attention from scholars at home and abroad.

[0004] The existing tensile honeycomb structure has a complex artificially designed microstructure. Application No. 202010198312.3 is a two-dimensional double-arrow negative Poisson's ratio structure and its interlocking assembly process. The first group of two-dimensional double-arrow elements are arranged in parallel and distributed in several rows along the X-axis direction, and the second group of two-dimensional double-arrow elements are arranged in several columns along the Y-axis direction. Slots are made at the intersection of the elements and assembled and interlocked. During the stacking process, the adhesion between layers is reduced, the assembly error generated during the assembly process is reduced, and the compressive strength of the structure is improved. However, the two-dimensional double-arrow element itself has the problem of being difficult to produce and prepare using traditional production technology. It usually needs to be prepared by additive manufacturing, which is expensive and cannot be mass-produced.

[0005] Therefore, developing an assembled tensile honeycomb structure that is easy to disassemble and assemble, efficient and controllable, saving time, materials and labor costs caused by disassembly and assembly as well as production and manufacturing, and being able to quickly and efficiently build the structural system required in actual engineering projects according to relevant needs is a very meaningful research direction at present, which is of great value for improving material utilization and realizing the widespread production and application of tensile honeycomb structures. Summary of the invention

[0006] One object of the present invention is to provide a double-arrow assembled honeycomb structure based on a straight-wall corrugated folded plate, comprising a first connecting plate, a middle negative Poisson's ratio sandwich layer, and a second connecting plate, wherein the middle negative Poisson's ratio sandwich layer is a layered, detachable double-arrow assembly structure composed of a long folded plate and a short folded plate structure, and two adjacent double-arrow assembly structures are also detachably connected. The advantage of this structure is that it has better energy absorption and impact resistance while being easier to disassemble and prepare, and the negative Poisson's ratio honeycomb has higher compression stiffness and strength.

[0007] This purpose is achieved by adopting the following technical solutions:

[0008] A double-arrow assembled honeycomb structure comprises a first connecting plate, a negative Poisson's ratio sandwich layer and a second connecting plate, wherein the negative Poisson's ratio sandwich layer is located between the first connecting plate and the second connecting plate, and the negative Poisson's ratio sandwich layer comprises a plurality of double-arrow assembled structures, wherein the plurality of double-arrow assembled structures are detachably connected from top to bottom. The double-arrow assembled structure comprises a detachably connected long folding plate and a short folding plate, and when the long folding plate and the short folding plate are connected, a double-arrow assembled structure is formed.

[0009] Among them, the long folding plate includes a plurality of long arrow units connected in sequence, and a plurality of long arrow units are connected in sequence from left to right to obtain a long folding plate; the short folding plate includes a plurality of short arrow units connected in sequence, and a plurality of short arrow units are connected in sequence from left to right to obtain a short folding plate; in a double arrow assembly structure, the long arrow units and the short arrow units correspond to each other one by one;

[0010] The long arrow unit includes two long plates connected at one end, and the two long plates are both provided with a first card slot and a second card slot opened at the side of the long plates; the short arrow unit includes two short plates connected at one end, and the two short plates are both provided with a third card slot and a fourth card slot opened at the side of the short plates;

[0011] When the long folding plate and the short folding plate are connected, the second slots of the two long plates of the long arrow unit are respectively engaged and connected with the third slots of the two short plates of the corresponding short arrow unit to obtain a double-arrow assembly structure.

[0012] When two adjacent double-arrow assembly structures are connected, the first slot of the long plate of the long folding plate is correspondingly engaged with the fourth slot of the short plate of the short folding plate. After connecting multiple double-arrow assembly structures, the negative Poisson's ratio sandwich layer of the present invention is obtained.

[0013] The present invention is a layered structure, wherein the first connecting plate, the negative Poisson's ratio sandwich layer, and the second connecting plate are arranged in sequence. The negative Poisson's ratio sandwich layer includes a plurality of double-arrow assembly structures, in which two short plates of the short arrow unit are cross-connected with two long plates of the long arrow unit, and when the structure is impacted in the X-axis direction in the two-dimensional direction, the two cross-connected short plates and the two long plates can interact with each other to form a self-locking.

[0014] Multiple double-arrow assembly structures of the structure are connected to form a negative Poisson's ratio sandwich layer. In two adjacent double-arrow assembly structures, the two short plates of the short arrow unit of one double-arrow assembly structure are cross-connected with the two long plates of the long arrow unit of the other double-arrow assembly structure. When the structure is impacted in the Y-axis direction in the two-dimensional direction, the two cross-connected short plates and the two long plates can interact with each other to form self-locking.

[0015] At the same time, the locking position of this structure is axially grooved along the Z axis of the structure, and a locking groove is set. The Z axis direction of the structure is the width direction of the long board and the short board, wherein the width of the long board and the short board is H, and the length of the locking groove is H / 2.

[0016] The long plate and the short plate of the double-arrow assembly structure are interlocked. When the structure is subjected to an impact load in any direction in the plane, the long plate and the short plate can be restrained from each other due to the cross-connection restriction of the long plate and the short plate, and will not separate. Also, because any impact load in the plane is perpendicular to the Z axis, it will only cause squeezing of the slotted position, and will not cause the self-locking system of the structure to be destroyed.

[0017] Compared with the existing structure, this structure does not need to install a restraining device on the outside or process a connecting device on the inside, and can achieve a self-locking effect during actual use, will not produce lateral splashing, and has strong economy and applicability.

[0018] Secondly, the double-arrow assembled honeycomb structure of the present structure has better energy absorption and impact resistance effects compared with the existing energy absorption structure.

[0019] Furthermore, the two long plates in the long arrow unit are symmetrically arranged, and the angle between the two long plates and the symmetry axis is θ1; the two short plates in the short arrow unit are symmetrically arranged, and the angle between the two short plates and the symmetry axis is θ2, 90°>θ2>θ1>0°.

[0020] The thickness of the long plate and the short plate is t, and the distance between the lower end of the long folding plate and the lower end of the short folding plate in the double-arrow assembly structure is S3, wherein S3>t / 2sinθ1+t / 2sinθ2.

[0021] In two adjacent double-arrow assembly structures, the distance between the upper end of the long folding plate of one double-arrow assembly structure and the upper end of the short folding plate of the other double-arrow assembly structure is S1; wherein S1>t / 2sinθ1+t / 2sinθ2.

[0022] The first double-arrow assembly structure, the second double-arrow assembly structure and the third double-arrow assembly structure are connected in sequence, and the distance between the upper end of the long folding plate of the first double-arrow assembly structure and the lower end of the short folding plate of the third is S2, wherein S2>t / sinθ2.

[0023] The distance between the other ends of the two long plates in the long arrow unit is the same as the distance between the other ends of the two short plates in the short arrow unit.

[0024] The height of the long folding plate is Y1, and the height of the short folding plate is Y2, wherein S2=Y1-Y2-2S1-S3.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] The present invention has a layered structure, and the middle negative Poisson's ratio sandwich layer can achieve self-locking during a two-dimensional impact process, that is, there is no need to install a restraining device on the outside or process a connecting device on the inside, and it has strong economy and applicability.

[0027] The preparation of the present invention can be completed only by cutting and mold stamping or bending, without the need for preparation by 3D printing technology. It can be manufactured by traditional preparation technology, with simple process flow, fast manufacturing speed, low price and high economic benefit.

[0028] The present invention is easy to disassemble and install, no positioning device is needed between the substructures during the assembly process, the installation has no technical difficulty, consumes little time, and can meet the assembly needs of emergency situations.

[0029] The negative Poisson's ratio sandwich layer of the present invention is composed of a plurality of long folding plates and short folding plates. The sizes of the long folding plates and the short folding plates can be freely selected according to the site conditions, the number of layers can be controlled, and the scale of the self-locking system can be adjusted at any time, which has good flexibility and adjustability.

[0030] The negative Poisson's ratio sandwich layer of the present invention has a negative Poisson's ratio effect (tensile expansion effect) and has many unique mechanical properties, such as higher compression stiffness and strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0032] Figure 1 and Figure 2 This is a schematic diagram of the double-arrow assembled honeycomb structure in Example 1;

[0033] Figure 3 It is a schematic diagram of the double-arrow assembly structure in Example 1;

[0034] Figure 4 This is a schematic diagram of the long folding plate structure in Example 1;

[0035] Figure 5 This is a schematic diagram of the short folded plate structure in Example 1;

[0036] Figure 6 This is a structural schematic diagram of several double-arrow assembly structures in Example 1 connected in sequence;

[0037] Figure 7 This is a schematic diagram of the structure of the angle θ1 in Example 2;

[0038] Figure 8 This is a schematic diagram of the structure of the angle θ2 in Example 2;

[0039] Fig. 9Schematic diagram of the positional relationship among S1, S2 and S3 in Example 2;

[0040] Fig.10 It is a schematic diagram of the relationship between the double-arrow assembled honeycomb structure and the existing double-arrow structure regarding the upper plate support reaction force and compression ratio.

[0041] Marks and corresponding parts names in the attached drawings:

[0042] 1-long board, 2-first card slot, 3-second card slot, 4-short board, 5-third card slot, 6-fourth card slot, 7-long folding board, 8-short folding board, 9-first connecting board, 10-second connecting board. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0044] In the description of the present invention, it should be understood that the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inside", "outside", etc., indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the scope of protection of the present invention.

[0045] Example 1

[0046] Double arrow assembled honeycomb structure Figure 1 and Figure 2 As shown, it includes a first connecting plate 9, a negative Poisson's ratio sandwich layer and a second connecting plate 10, and the negative Poisson's ratio sandwich layer is located between the first connecting plate 9 and the second connecting plate 10. The first connecting plate 9, the negative Poisson's ratio sandwich layer and the second connecting plate 10 are connected to each other by laser welding. Among them, the first connecting plate 9 and the second connecting plate 10 are both solid aluminum alloy flat plates prepared by cold rolling process. The negative Poisson's ratio sandwich layer includes a number of double-arrow assembly structures, and the double-arrow assembly structures are as shown in FIG. Figure 3 As shown, the double-arrow assembly structure includes a detachably connected long folding plate 7 and a short folding plate 8, and the lower end of the long folding plate 7 is cross-connected with the lower end of the short folding plate 8.

[0047] Among them, Figure 4As shown, the long folding plate 7 includes a plurality of long arrow units connected in sequence, and a long folding plate is obtained by connecting the plurality of long arrow units in sequence from left to right. The long arrow unit includes two long plates 1 connected at one end, and the two long plates 1 are provided with a first card slot 2 and a second card slot 3 opened on the side of the long plate 1; in some embodiments, the number of long arrow units in the long folding plate 7 can be adjusted according to actual usage.

[0048] like Figure 5 As shown, the short folding plate 8 includes a plurality of short arrow units connected in sequence, and a plurality of short arrow units are connected in sequence from left to right to obtain a short folding plate; the short arrow unit includes two short plates 4 connected at one end, and the two short plates 4 are both provided with a third card slot 5 and a fourth card slot 6 opened on the side of the short plate 4; in some embodiments, the number of short arrow units in the short folding plate 8 can be adjusted according to actual usage.

[0049] like Figure 6 As shown, several double-arrow assembly structures are detachably connected from top to bottom in sequence. When two adjacent double-arrow assembly structures are connected, the first card slot 2 of the long plate 1 of the long folding plate 7 and the fourth card slot 6 of the short plate 4 of the short folding plate 8 are correspondingly engaged and connected. After connecting multiple double-arrow assembly structures, the double-arrow assembled honeycomb structure of the present invention is obtained.

[0050] Example 2

[0051] On the basis of the above embodiment, the two long plates 1 in the long arrow unit are symmetrically arranged, such as Figure 7 As shown, the angle between the two long plates 1 and the symmetry axis is θ1, and the two short plates 4 in the short arrow unit are symmetrically arranged, as shown in FIG. Figure 8 As shown, the angle between the two short plates 4 and the symmetry axis is θ2, 90°>θ2>θ1>0°. The thickness of the long plate 1 and the short plate 4 is t, the distance between the other ends of the two long plates 1 in the long arrow unit is L, and the distance between the other ends of the two short plates 4 in the short arrow unit is L.

[0052] like Fig. 9 As shown, the distance between the lower end of the long folding plate 7 and the lower end of the short folding plate 8 in the double-arrow assembly structure is S3, wherein S3>t / 2sinθ1+t / 2sinθ2.

[0053] In two adjacent double-arrow assembly structures, the distance between the upper end of the long folding plate 7 of one double-arrow assembly structure and the upper end of the short folding plate 8 of the other double-arrow assembly structure is S1; wherein S1>t / 2sinθ1+t / 2sinθ2.

[0054] The first double-arrow assembly structure, the second double-arrow assembly structure and the third double-arrow assembly structure are connected in sequence, and the distance between the upper end of the long folding plate 7 of the first double-arrow assembly structure and the lower end of the short folding plate 8 of the third is S2, wherein S2>t / sinθ2.

[0055] The height of the long folding plate 7 is Y1, and the height of the short folding plate 8 is Y2, wherein S2=Y1-Y2-2S1-S3.

[0056] The locking position of this structure is an axial groove along the Z axis of the structure, and a locking groove is set. The Z axis direction of the structure is the width direction of the long board 1 and the short board 4, wherein the width of the long board 1 and the short board 4 are both H, and the length of the locking groove is H / 2, wherein the longer the axial length H is, the better the self-locking effect is.

[0057] When the structure has n layers, the total height of the main structure is A=1+nS1+nS2+S3+Y2.

[0058] Preferably, θ1:θ2=1:1.5-3.5, θ1=5-30°.

[0059] Example 3

[0060] Based on the above embodiment, θ1=25°, θ2=50°, Y1=30, Y2=10, t=0.5mm, S1=1.2, S3=1.5, S2=16.1, H=30.

[0061] The double-arrow assembled honeycomb structure with negative Poisson's ratio core layer in this embodiment and the existing double-arrow structure are axially compressed to obtain energy absorption characteristics. The double-arrow assembled honeycomb structure and the existing double-arrow structure have the same number of layers and the same number of double-arrow units in each layer.

[0062] A dynamic axial compression test was conducted on the double-arrow assembled honeycomb structure and the existing double-arrow structure. The experiment obtained a schematic diagram of the double-arrow assembled honeycomb structure and the existing double-arrow structure regarding the upper plate support reaction force and compression ratio. The schematic diagram is shown in FIG. Fig.10 shown.

[0063] Among them, specific mass energy absorption and energy absorption efficiency are two important energy absorption performance evaluation indicators.

[0064] The specific mass energy absorption of the structure of the present invention is greater than that of the existing double-arrow structure, which is 1.74 times that of the existing double-arrow structure.

[0065] The energy absorption efficiency of the structure of the present invention is 2.69 times that of the existing double-arrow structure.

[0066] The initial peak stress of the structure of the present invention is 0.7 times that of the existing double-arrow structure. This smaller value indicates that the structure is less likely to be damaged when encountering a sudden impact load, and is more conducive to building an energy absorption system.

[0067] In summary, experiments have shown that the structural configuration of the present invention is more suitable for developing energy absorption systems than the existing double-arrow structure.

[0068] The terms "first", "second", "third", etc. used herein are only used to distinguish the corresponding components for the sake of clarity of description, and are not intended to limit any order or emphasize importance, etc. In addition, the term "connected" used herein, unless otherwise specified, may refer to direct connection or indirect connection via other components.

[0069] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. Double-arrow assembled honeycomb structure, characterized in that: It comprises a first connecting plate (9), a negative Poisson's ratio sandwich layer and a second connecting plate (10), wherein the negative Poisson's ratio sandwich layer is located between the first connecting plate (9) and the second connecting plate (10), and the negative Poisson's ratio sandwich layer comprises a plurality of double-arrow assembly structures, wherein the double-arrow assembly structures comprise a long folding plate (7) and a short folding plate (8) that are detachably connected; The long folding plate (7) includes a plurality of long arrow units connected in sequence, and the short folding plate (8) includes a plurality of short arrow units connected in sequence, and the long arrow units and the short arrow units in the double-arrow assembly structure correspond to each other one by one; The long arrow unit comprises two long plates (1) connected at one end, and the two long plates (1) are both provided with a second slot (3) opened at the side of the long plates (1); the short arrow unit comprises two short plates (4) connected at one end, and the two short plates (4) are both provided with a third slot (5) opened at the side of the short plates (4); When the long folding plate (7) and the short folding plate (8) are connected, the second clamping grooves (3) of the two long plates (1) of the long arrow unit are respectively clamped and connected with the third clamping grooves (5) of the two short plates (4) of the corresponding short arrow unit; The two long plates (1) in the long arrow unit are symmetrically arranged, and the angle between the two long plates (1) and the symmetry axis is θ1; the two short plates (4) in the short arrow unit are symmetrically arranged, and the angle between the two short plates (4) and the symmetry axis is θ2, 90°>θ2>θ1>0°; the thickness of the long plate (1) and the short plate (4) is t, and the distance between the lower end of the long folding plate (7) and the lower end of the short folding plate (8) in the double arrow assembly structure is S3, wherein S3>t / 2sinθ1+t / 2sinθ2; in two adjacent double arrow assembly structures, the long folding plate of one of the double arrow assembly structures The distance between the upper end of the long folding plate (7) and the upper end of the short folding plate (8) of another double-arrow assembly structure is S1; wherein S1>t / 2sinθ1+t / 2sinθ2; the first double-arrow assembly structure, the second double-arrow assembly structure and the third double-arrow assembly structure are connected in sequence, and the distance between the upper end of the long folding plate (7) of the first double-arrow assembly structure and the lower end of the short folding plate (8) of the third double-arrow assembly structure is S2, wherein S2>t / sinθ2; the height of the long folding plate (7) is Y1, and the height of the short folding plate (8) is Y2, wherein S2=Y1-Y2-2S1-S3.

2. The double-arrow assembled honeycomb structure according to claim 1, characterized in that: The structure is provided with an embedding groove at the embedding position, the width of the long plate (1) and the short plate (4) are both H, and the length of the embedding groove is H / 2.

3. The double-arrow assembled honeycomb structure according to claim 1, characterized in that: The distance between the other ends of the two long plates (1) in the long arrow unit is the same as the distance between the other ends of the two short plates (4) in the short arrow unit.

4. The double-arrow assembled honeycomb structure according to claim 1, characterized in that: The two long plates (1) are each provided with a first card slot (2) opened on the side of the long plate (1), and the two short plates (4) are each provided with a fourth card slot (6) opened on the side of the short plate (4); two adjacent double-arrow assembly structures are detachably connected, and when the two double-arrow assembly structures are connected, the first card slot (2) of the long plate (1) of the long folding plate (7) and the fourth card slot (6) of the short plate (4) of the short folding plate (8) are correspondingly engaged and connected.

5. The double-arrow assembled honeycomb structure according to claim 1, characterized in that: The first connecting plate and the second connecting plate are solid plates, and the materials of the first connecting plate (9), the second connecting plate (10) and the negative Poisson's ratio sandwich layer are all one of aluminum alloy or stainless steel; the first connecting plate (9) and the second connecting plate (10) are prepared by rolling, and the long folding plate (7) and the short folding plate (8) are prepared by cutting and grooving and then die stamping or bending; the negative Poisson's ratio sandwich layer and the first connecting plate (9) and the second connecting plate (10) are all welded.

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