Energy-absorbing element and energy-absorbing buffer including the energy-absorbing element

Abstract

This invention discloses an energy-absorbing element and its energy-absorbing buffer. The energy-absorbing element comprises at least two structural units in the form of truncated conical shells. The structural units are sequentially stacked along their own axes to form a layered sleeve structure, with circumferential overlapping interfaces between the side walls of adjacent structural units. When an external load is applied to the energy-absorbing element, the structural units can exhibit circumferential elastic strain under the interaction force of the circumferential overlapping interfaces between adjacent structural units, enabling interface slippage between adjacent structural units. The energy-absorbing element of this invention not only inherits the advantages of discrete structures (the structure can be disassembled and assembled, and individual components can be replaced after failure), but also possesses the characteristics of a "circumferential stress-dominated" structure, i.e., high load-bearing capacity. Simultaneously, the structure has good energy dissipation capacity, thus possessing good buffering and vibration reduction performance. Moreover, the presence of the circumferential overlapping interfaces effectively hinders crack propagation.

Description

Technical Field

[0001] This invention relates to the field of vibration energy absorption and dissipation technology, and particularly to an energy-absorbing element and an energy-absorbing buffer including the energy-absorbing element. Background Technology

[0002] The demand for lightweight, multifunctional structures is becoming increasingly urgent for next-generation aerospace design missions. New application scenarios are also placing new demands on multifunctional structures. Manned deep space exploration requires deployable and scalable multifunctional structures as temporary energy-absorbing buffers and vibration-damping platforms for equipment. Scenarios such as space station docking and spacecraft landing in outer space not only require lightweight structures as energy-absorbing and vibration-damping devices, but also require these structures to be reusable (not irreversibly damaged after impact and can be reused) or recyclable (i.e., some components can be recovered and reused after failure) to reduce transportation costs.

[0003] Therefore, it is particularly necessary to design an energy-absorbing element that has both good load-bearing performance and light weight, as well as functions such as buffering and energy absorption, shock absorption and noise reduction, scalability, easy repair or recyclability. Summary of the Invention

[0004] In view of this, the present invention provides an energy-absorbing element and an energy-absorbing buffer including the energy-absorbing element, which not only has high load-bearing capacity, but also has good energy dissipation capacity, thereby possessing good buffering and vibration reduction functions.

[0005] The first aspect of this invention discloses an energy-absorbing element comprising at least two structural units, each structural unit being a truncated conical shell with an internal hollow structure; the at least two structural units are sequentially stacked along their own axial direction to form a layered sleeve structure, with the side walls of adjacent structural units at least partially in circumferential contact and overlapping to have a circumferential overlapping interface; the structural units are designed such that when an external load is applied to the energy-absorbing element, the structural units can have circumferential elastic strain under the interaction force of the circumferential overlapping interface between adjacent structural units, allowing for interface slip between adjacent structural units, thereby dissipating energy through friction during the interface slip process.

[0006] In this invention, the energy-absorbing element is formed by sequentially stacking at least two truncated conical shells along the axial direction. This allows the energy-absorbing element to inherit the advantages of discrete structures, such as simple manufacturing processes, high design flexibility, and the ability to transport individual discrete components separately and assemble and deploy them according to actual working conditions. It also possesses the characteristics of a "circumferential stress-dominated" structure, i.e., high load-bearing capacity. Simultaneously, the presence of circumferentially overlapping interfaces effectively hinders crack propagation, and the interfacial slip between adjacent structural units provides excellent energy dissipation capabilities, resulting in good buffering and vibration reduction performance. Furthermore, the combination of multiple mechanisms also contributes to the structure's recyclability, enabling it to be used as a recyclable multifunctional device in various fields such as aerospace.

[0007] Furthermore, the energy-absorbing element of this invention is actually a "circumferential stress-dominated" sleeve-type discrete structure system. In this system, each structural unit acts as a sleeve-type discrete element, and adjacent discrete elements have circumferential overlapping interfaces. This allows the structural unit to exhibit circumferential elastic strain under the interaction force of the circumferential overlapping interfaces between adjacent structural units when an external load is applied to the energy-absorbing element, enabling interface slip between adjacent structural units. That is, in the energy-absorbing element of this invention, the overall axial deformation of the structure is closely related to the interface slip between structural units. The circumferential elastic strain of a single structural unit determines the magnitude of the interface slip, which in turn depends on the interaction force between the structural units. This creates a mechanism in which interface slip and structural deformation are coupled together. Based on this mechanism, when subjected to impact or vibration loads, the presence of the circumferential overlapping interfaces causes significant differences in the energy dissipation, crack propagation, and material damage characteristics of the structure compared to traditional "integral (also known as continuous)" structures.

[0008] Furthermore, the energy-absorbing element is designed such that when the external load exceeds a predetermined critical load, at least one structural unit within the energy-absorbing element undergoes plastic deformation to dissipate the energy generated during load application. Preferably, when the external load exceeds the predetermined critical load, the truncated conical shell located at the uppermost and / or lowermost end of the energy-absorbing element undergoes plastic deformation. That is, when the external load exceeds the critical load of the energy-absorbing element, energy is dissipated by the destruction of at least one structural unit. Here, destruction refers to destructive plastic deformation, through which energy is "absorbed." Although this deformation is irreversible, since the energy-absorbing element of the present invention is a discrete structure, i.e., formed by stacking multiple structural units, even if one or more of the structures undergoes irreversible destruction, they can be replaced individually, and the other structural units can continue to be used. The critical load refers to the maximum load that the energy-absorbing element can withstand before the structural unit is destroyed; when this critical load is exceeded, one or more structural units of the energy-absorbing element will undergo plastic deformation and destruction. The critical load can be determined in advance through calculation, and is not limited here.

[0009] As can be seen from the above, in this invention, before the external load reaches the predetermined critical load of the energy-absorbing element, the energy-absorbing element dissipates the energy generated during the application of the load by means of friction caused by the interface slippage between adjacent structural units; and when the external load exceeds the predetermined critical load of the energy-absorbing element, the energy-absorbing element dissipates the energy generated during the application of the load by means of the plastic deformation of the structural units therein.

[0010] Compared to a single truncated conical shell that absorbs energy through mechanisms such as local buckling and plastic deformation, the sleeve structure formed by stacking multiple truncated conical shells in this invention dissipates energy through interfacial friction under small deformations, and absorbs energy through the fracture of a single truncated conical shell after reaching the critical load. Moreover, because it is designed as a sleeve structure, it can be transported separately and assembled into energy-absorbing elements according to actual engineering needs. If a single truncated conical shell is damaged, it can be replaced, while the other structural units can continue to be used.

[0011] Furthermore, the height of the overlapping section between adjacent structural units in the axial direction of the structural unit exceeds one-third of the height of the structural unit itself. This allows for the formation of a large-area circumferential overlapping interface between adjacent structural units. On the one hand, it provides good load-bearing performance in the initial state; on the other hand, when subjected to impact or vibration loads, the large contact interface can provide sufficient circumferential elastic deformation to achieve relatively stable interface slippage, thereby providing stable buffering performance.

[0012] Furthermore, more than three structural units are provided, and in each of the three sequentially adjacent structural units, there is an overlapping area between the overlapping interface between the upper structural unit and the middle structural unit and between the lower structural unit and the middle structural unit. This feature allows the structural units in the energy-absorbing element of this invention to maintain good overall cooperation while possessing their individual discrete advantages. Specifically, when subjected to impact or vibration loads, it is not only the two energy-absorbing elements closest to the impact point that dissipate the vibration energy, but also, thanks to the aforementioned overlapping area, the vibration energy can be transferred from top to bottom, allowing each structural unit in the energy-absorbing element to participate in the work, thereby optimizing the dissipation of vibration energy. In addition, due to the existence of the aforementioned overlapping area, the overall load-bearing capacity of the energy-absorbing element is better in the initial state.

[0013] Furthermore, the cone angle of the structural unit is greater than or equal to 45° and less than or equal to 85°. The cone angle refers to the angle between the larger end of the side wall of the structural unit, which is a truncated conical shell, and the horizontal direction. In a preferred embodiment, the cone angle is 70°, 75°, or 80°.

[0014] Furthermore, the structural units are made of isotropic materials. Specifically, the structural units are made of isotropic materials selected from one of the following: alumina, silicon carbide, titanium diboride, silicon carbide, beryllium oxide, silicon nitride, titanium alloy, aluminum alloy, steel, polyetheretherketone (PEEK), polyamide (PA), polypropylene (PP), polyethylene terephthalate (PETG), ABS, PLA, and polytetrafluoroethylene (PTEF).

[0015] A second aspect of the present invention also discloses an energy-absorbing buffer, which includes a retainer and an energy-absorbing element as described above, wherein at least one set of energy-absorbing elements is provided, and the retainer holds the energy-absorbing element from the outside.

[0016] In one embodiment, the retainer is a honeycomb structure made of a flexible material, comprising a plurality of honeycomb cells arranged in relation to each other, each honeycomb cell having at least one honeycomb cell cavity, and each honeycomb cell cavity having at least one set of energy-absorbing elements.

[0017] Furthermore, the honeycomb cell is a regular polygon, and the outer edge of the larger end of each structural unit of the energy-absorbing element maintains tangential contact with the inner wall of the corresponding honeycomb cell cavity. Through this tangential contact between the structural unit and the inner wall of the honeycomb cell cavity, when the energy-absorbing element dissipates vibrational load energy, a portion of the energy absorbed by the energy-absorbing element can be transferred to the retainer through contact with the honeycomb retainer. That is, the retainer can also participate in energy dissipation, thus forming a synergistic integral energy-absorbing buffer between the energy-absorbing element and the honeycomb retainer. By leveraging the combined energy absorption effect of the energy-absorbing element and the honeycomb retainer, the energy dissipation capability of the energy-absorbing buffer of the present invention is greatly improved. Moreover, when the energy-absorbing element is subjected to radial load, radial vibration energy can be dissipated through the tangential contact between the structural unit and the inner wall of the honeycomb cell cavity.

[0018] In the energy-absorbing buffer of the first embodiment of the present invention, the energy-absorbing element is installed after the honeycomb retainer. In the initial state, the energy-absorbing element extends out of the honeycomb cell of the retainer at least at the uppermost structural unit portion. When the energy-absorbing element is subjected to axial load, the structural unit of the energy-absorbing element will undergo circumferential elastic deformation due to the interaction force between the circumferential overlapping interfaces, thereby causing interface slippage between adjacent structural units of the energy-absorbing element. During this process, energy dissipation occurs due to friction.

[0019] In another embodiment, the retainer includes a plurality of retaining inserts arranged along the axial direction of the structural unit, one retaining insert corresponding to each layer of structural unit and sleeved and fixed on the outside of the corresponding layer of structural unit.

[0020] Beneficial Effects: In this invention, the energy-absorbing element is formed by sequentially stacking at least two truncated conical shells along the axial direction. This allows the energy-absorbing element to inherit the advantages of discrete structures, such as simple manufacturing processes, high design flexibility, and the ability to transport individual discrete components separately and assemble and deploy them according to actual working conditions. It also possesses the characteristics of a "circumferential stress-dominated" structure, i.e., high load-bearing capacity. Simultaneously, the presence of circumferential overlapping interfaces effectively hinders crack propagation, and the interface slippage between adjacent structural units provides excellent energy dissipation capabilities, resulting in good buffering and vibration reduction performance. Furthermore, the combination of multiple mechanisms also contributes to the structure's recyclability, enabling it to be used as a recyclable multifunctional device in aerospace and other fields.

[0021] The energy-absorbing element of the present invention and the energy-absorbing buffer including the energy-absorbing element are disclosed in detail below with reference to the embodiments shown in the accompanying drawings and the reference numerals. Attached Figure Description

[0022] Figure 1 A perspective view of the energy-absorbing element of the present invention is shown;

[0023] Figure 2 A front view of the energy-absorbing element of the present invention is shown;

[0024] Figure 3 An axial cross-sectional view of the energy-absorbing element of the present invention is shown;

[0025] Figure 4 A perspective view of the structural unit in the energy-absorbing element of the present invention is shown;

[0026] Figure 5 A cross-sectional view of a structural unit in the energy-absorbing element of the present invention is shown;

[0027] Figure 6 A perspective view of the energy-absorbing buffer of the first embodiment is shown;

[0028] Figure 7 A top view of the energy-absorbing buffer of the first embodiment is shown;

[0029] Figure 8 A perspective view of the retainer in the energy-absorbing buffer of the first embodiment is shown;

[0030] Figure 9 A top view of the retainer in the energy-absorbing buffer of the first embodiment is shown;

[0031] Figure 10 A perspective view of the energy-absorbing buffer of the second embodiment is shown;

[0032] Figure 11 A top view of the energy-absorbing buffer of the second embodiment is shown;

[0033] Figure 12 A perspective view of the retainer in the energy-absorbing buffer of the second embodiment is shown;

[0034] Figure 13 A top view of the retainer in the energy-absorbing buffer of the second embodiment is shown.

[0035] Figure Labels

[0036] 1. Energy-absorbing element 6. Large end

[0037] 2 Energy Absorption Units 7 Side Walls

[0038] 3 Overlapping Interfaces 8 Retainers

[0039] 3a First Overlapping Interface 9 Honeycomb Cells

[0040] 3b Second overlapping interface 10 Cellular unit cavity

[0041] 4. Overlapping area 11. Maintain insert

[0042] 5 small end 12 insert holes Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0044] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0045] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0046] Combination Figures 1-5 As shown, this invention discloses an energy-absorbing element 1, which includes five structural units 2. Each structural unit 2 is a truncated conical shell with a hollow interior. The five structural units 2 are sequentially stacked along their own axial direction to form a layered sleeve structure, and the side walls of adjacent structural units 2 are at least partially in circumferential contact and overlap. In other preferred embodiments, two, three, or four structural units 2 can also be provided. Those skilled in the art will also understand that more than five structural units 2 can also be provided.

[0047] In this invention, structural unit 2 includes a small end 5 and a large end 6, and a side wall 7 extending from the small end 5 to the large end 6, the side wall 7 being a truncated cone shape. Structural unit 2 is designed such that when the load applied to the energy-absorbing element 1 exceeds the critical impact force at the end of the energy-absorbing element 1, structural unit 2 can exhibit circumferential elastic strain under the interaction force of the circumferential overlapping interface 3 between adjacent structural units 2, allowing for interface slippage between adjacent structural units 2.

[0048] In this invention, the cone angle θ of structural unit 2 is set to 80°. In other preferred embodiments, the cone angle θ can be set to 70° or 75°.

[0049] In this invention, the diameter D of the larger end of structural unit 2 is 10-40 cm, preferably 10 cm, 30 cm, or 40 cm, and the diameter d of the smaller end is 5-30 cm, preferably 5 cm, 10 cm, 22.5 cm, or 30 cm. The thickness of the side wall 7 of structural unit 2 is 1-2 cm, preferably 1 cm, 1.25 cm, 1.5 cm, or 2 cm. The height h of structural unit 2 is 10-25 cm, preferably 10 cm, 15 cm, 21.27 cm, or 25 cm. The total height H of the energy-absorbing element is 15 to 50 cm.

[0050] In this invention, the height of the overlapping section between adjacent structural units 2 in the axial direction of structural unit 2 exceeds one-third of the height h of structural unit 2 itself. This allows for the formation of a large-area circumferential overlapping interface 3 between adjacent structural units 2. On the one hand, it provides good load-bearing performance in the initial state; on the other hand, when subjected to impact or vibration loads, it can provide sufficient circumferential elastic deformation by means of the large contact interface to achieve relatively stable interface slippage, thereby providing stable buffering performance.

[0051] In embodiments of the present invention, in each of three sequentially adjacent structural units 2, there is an overlapping region 4 between the first overlapping interface 3a between the upper structural unit 2 and the middle structural unit 2 and the second overlapping interface 3b between the lower structural unit 2 and the middle structural unit 2. The overlapping region refers to a positional overlap, not that the first overlapping interface 3a and the second overlapping interface 3b are in direct contact. By virtue of the overlapping region 4, the structural units 2 in the energy-absorbing element 1 of the present invention can maintain good overall cooperation while possessing their individual discrete advantages.

[0052] In this invention, structural unit 2 is made of an isotropic material. Specifically, structural unit 2 is made of an isotropic material selected from one of the following: alumina, silicon carbide, titanium diboride, silicon carbide, beryllium oxide, silicon nitride, titanium alloy, aluminum alloy, steel, polyetheretherketone (PEEK), polyamide (PA), polypropylene (PP), polyethylene terephthalate (PETG), ABS material, PLA material, and polytetrafluoroethylene (PTEF).

[0053] In other embodiments, the structural units of the energy-absorbing element are made of transversely isotropic materials, such as fiber-reinforced composites.

[0054] The present invention also discloses an energy-absorbing buffer comprising the aforementioned energy-absorbing element 1.

[0055] Combination Figures 6-9 As shown, the present invention discloses an energy-absorbing buffer according to a first embodiment. In this embodiment, the energy-absorbing buffer includes a retainer 8 and, as shown... Figures 1-5 The energy-absorbing element 1 shown is held in place by the retainer 8 from the outside.

[0056] In this embodiment, the retainer 8 is a honeycomb structure made of a flexible material, comprising a plurality of honeycomb cells 9 arranged in relation to each other. Each honeycomb cell 9 has a honeycomb cell cavity 10, and a set of energy-absorbing elements 1 is disposed within each honeycomb cell cavity 10. Of course, those skilled in the art will understand that each honeycomb cell 9 can have more than one honeycomb cell cavity 10, such as two or three, and more than one set of energy-absorbing elements 1 can be disposed within each honeycomb cell cavity 10, such as simultaneously providing two or three sets of honeycomb cell cavities 10. The honeycomb retainer is made of TPU or rubber material.

[0057] In this embodiment, the honeycomb cell 9 is a regular polygon shape, preferably a regular hexagon shape. The outer edge of the larger end of each structural unit 2 of the energy-absorbing element 1 is in tangential contact with the inner wall of the corresponding honeycomb cell cavity 10.

[0058] Furthermore, in this embodiment, after the energy-absorbing element 1 is installed in the honeycomb retainer 8, in the initial state, at least the uppermost structural unit 2 of the energy-absorbing element 1 extends (exposes) from the honeycomb cell 9 of the retainer 8. When the energy-absorbing element 1 is subjected to an axial load, the structural unit 2 of the energy-absorbing element 1 will undergo circumferential elastic deformation due to the interaction force between the circumferential overlapping interfaces 3, thereby causing interface slippage between adjacent structural units 2 of the energy-absorbing element 1. In this process, energy dissipation of axial load will occur. In addition, during this process, the uppermost end of the energy-absorbing element 1 will slowly move closer to the honeycomb cell 9 due to the interface slippage between the structural units 2. When the axial load is large enough, the uppermost end of the energy-absorbing element 1 will remain horizontal and level with the upper end of the honeycomb cell 9 due to the interface slippage. In this state, the honeycomb retainer 8 will also participate in bearing the load, that is, the energy-absorbing element 1 and the honeycomb retainer 8 will jointly bear the axial load, and the honeycomb retainer 8 and the energy-absorbing element 1 will jointly dissipate the vibration energy caused by the large axial load.

[0059] Combination Figures 10-13 As shown, the present invention discloses a second embodiment of an energy-absorbing buffer. In this second embodiment of the energy-absorbing buffer, the retainer 8 includes a plurality of retaining inserts 11 arranged along the axial direction of the structural unit 2. One retaining insert 11 is provided for each layer of structural unit 2 and is sleeved and fixed on the outside of the corresponding layer of structural unit 2. The retaining insert 11 is provided with insert holes 12 for receiving the corresponding layer of structural unit 2.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An energy-absorbing buffer, characterized in that, The energy-absorbing buffer includes a retainer and an energy-absorbing element, wherein the retainer holds the energy-absorbing element from the outside. The energy-absorbing element includes at least two structural units, each of which is a hollow truncated conical shell. The at least two structural units are sequentially stacked in their own axial direction to form a stacked sleeve structure. The side walls of adjacent structural units are at least partially in circumferential contact and overlap to have a circumferential overlapping interface. The structural units are designed such that when an external load is applied to the energy-absorbing element, the structural units can have circumferential elastic strain under the interaction force of the circumferential overlapping interface between adjacent structural units, so that there can be interface slip between adjacent structural units to dissipate the energy generated during the load application process. The retainer is a honeycomb structure made of flexible material, comprising a plurality of honeycomb cells arranged in relation to each other, each honeycomb cell having at least one honeycomb cell cavity, and at least one set of energy-absorbing elements disposed within each honeycomb cell cavity; The honeycomb cell is a regular polygon shape, and the outer edge of the large end of each structural unit of the energy-absorbing element is in tangential contact with the inner wall of the corresponding honeycomb cell cavity.

2. The energy-absorbing element according to claim 1, characterized in that, The energy-absorbing element is designed such that when the external load exceeds the predetermined critical load of the energy-absorbing element, at least one structural unit in the energy-absorbing element can undergo plastic deformation to dissipate the energy generated during the load application process.

3. The energy-absorbing element according to claim 1, characterized in that, The overlapping section between adjacent structural units has a height exceeding one-third of the structural unit's own height along the structural unit's axis.

4. The energy-absorbing element according to claim 1, characterized in that, The structural unit is provided in more than three parts, wherein in each of the three adjacent structural units, there is an overlapping area between the overlapping interface between the upper structural unit and the middle structural unit and between the overlapping interface between the lower structural unit and the middle structural unit.

5. The energy-absorbing element according to claim 1, characterized in that, The cone angle of the structural unit is greater than or equal to 45° and less than or equal to 85°.

6. The energy-absorbing element according to claim 1, characterized in that, The structural unit is made of an isotropic material selected from one of the following: alumina, silicon carbide, titanium diboride, beryllium oxide, silicon nitride, titanium alloy, aluminum alloy, steel, polyetheretherketone, polyamide, polypropylene, polyethylene terephthalate, ABS, PLA, and polytetrafluoroethylene.

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