Sound-absorbing impact-resistant superstructure, preparation method and sound-absorbing device

Abstract

The invention relates to the technical field of sound absorption and noise reduction, and discloses a sound absorption and impact resistance superstructure, a preparation method and a sound absorption device.The sound absorption and impact resistance superstructure comprises a plurality of impact resistance sound absorption assemblies which are fixedly connected in a stacked mode, each impact resistance sound absorption assembly comprises a sound absorption shell, a cover plate and an impact resistance unit, and a sound absorption channel is formed in the sound absorption shell; the cover plate is located on one side of the sound absorption shell and covers one opening of the sound absorption channel, and a hole channel communicated with the sound absorption channel is formed in the cover plate. The anti-impact unit is arranged in the sound absorption channel, and the anti-impact unit is provided with a first cavity channel penetrating in the first direction. According to the sound-absorbing and impact-resisting superstructure, the impact-resisting units are arranged in the sound-absorbing channels, so that when the sound-absorbing and impact-resisting superstructure is impacted, impact energy can be effectively absorbed, impact damage is reduced, the sound-absorbing and impact-resisting performance of the superstructure can be coordinated, and the safety protection level can be improved.

Description

Technical Field

[0001] This invention relates to the field of sound absorption and noise reduction technology, and in particular to a sound-absorbing and impact-resistant superstructure, its preparation method, and a sound-absorbing device. Background Technology

[0002] With the widespread application of underwater devices (such as submarines, underwater drones, and seabed exploration equipment), the demand for underwater acoustic stealth technology is increasing. Underwater acoustic stealth structures not only need to effectively absorb sound waves emitted by targets, but also need to possess excellent shock resistance to cope with complex underwater environments.

[0003] Currently, underwater sound-absorbing structures designed using acoustic metamaterials can absorb sound waves in the low-frequency range to achieve a certain sound absorption effect. However, their impact resistance and durability are insufficient. When subjected to impacts such as water flow or explosive loads, they are prone to stress concentration, leading to local structural damage and affecting the service life of the sound-absorbing structure. Summary of the Invention

[0004] In order to solve the above-mentioned technical problems, or at least partially solve the above-mentioned technical problems, this application provides a sound-absorbing and impact-resistant superstructure, a preparation method, and a sound-absorbing device.

[0005] In a first aspect, this application provides a sound-absorbing and impact-resistant superstructure, comprising a plurality of impact-resistant sound-absorbing components stacked and fixedly connected along a first direction, wherein the impact-resistant sound-absorbing components include: The sound-absorbing shell has sound-absorbing channels inside. A cover plate, located on one side of the sound-absorbing shell, covers an opening of the sound-absorbing channel, and the cover plate has a channel communicating with the sound-absorbing channel; An impact-resistant unit is disposed within the sound-absorbing channel, the impact-resistant unit having a first cavity extending along the first direction; The impact-resistant unit includes multiple impact-resistant layers stacked along the first direction. Each impact-resistant layer has a through hole in its center. One impact-resistant layer near the cover plate abuts against the cover plate. The through holes of the multiple stacked impact-resistant layers are coaxially connected to form the first cavity. The projection of the cavity in the first cavity is located on the central axis of the first cavity. Each of the impact-resistant layers includes multiple impact-resistant components, which are assembled together in a single unit along the circumference of the sound-absorbing channel. The through-hole is formed by assembling multiple impact-resistant components along the circumference of the sound-absorbing channel.

[0006] In one embodiment, at least three impact-resistant sound-absorbing components are provided, namely an upper impact-resistant sound-absorbing component, a middle impact-resistant sound-absorbing component, and a lower impact-resistant sound-absorbing component that are stacked and fixedly connected in sequence along the first direction. The sound absorption channels of the upper impact-resistant sound absorption component, the middle impact-resistant sound absorption component, and the lower impact-resistant sound absorption component gradually increase in depth along the first direction, and the impact stiffness of the impact-resistant unit gradually increases.

[0007] In one embodiment, the upper impact-resistant sound-absorbing component includes a first impact-resistant member, which is a concave negative Poisson's ratio metamaterial cell. The concave negative Poisson's ratio metamaterial cell has a first reference line and a second reference line that pass through its center and are perpendicular to each other. The concave negative Poisson's ratio metamaterial cell includes two vertical cell walls and four inclined cell walls. The two vertical cell walls are symmetrically distributed at intervals around the first reference axis, and the four inclined cell walls are located within the space defined by the two vertical cell walls. The two inclined cell walls are connected at their closest ends to form a first concave bending structure, and their far ends are respectively connected to the upper ends of the two vertical cell walls. The other two inclined cell walls are connected at their closest ends to form a second concave bending structure, and their far ends are respectively connected to the lower ends of the two vertical cell walls. The first concave bending structure and the second concave bending structure are symmetrical about the second reference line.

[0008] In one embodiment, in the same impact-resistant layer of the upper impact-resistant sound-absorbing component, the vertical cell walls of two adjacent first impact-resistant members are in contact with each other; and / or, the end faces of the four inclined cell walls of two adjacent first impact-resistant members are in contact with each other.

[0009] In one embodiment, the distance H between the first concave bending structure and the second bending structure along the extension direction of the second reference line satisfies the following relationship: in, The length of the vertical cell wall is given.

[0010] In one embodiment, the middle layer impact-resistant sound-absorbing assembly includes a second impact-resistant member, the second impact-resistant member having a second cavity extending along the first direction; The second impact-resistant component includes multiple honeycomb panels, which are connected in sequence to form a regular hexagonal honeycomb structure.

[0011] In one embodiment, within the same impact-resistant layer of the middle impact-resistant sound-absorbing assembly, the surfaces of the honeycomb panels of two adjacent second impact-resistant members are bonded together; and / or, In the two adjacent impact-resistant layers of the middle impact-resistant sound-absorbing assembly, the end faces of the honeycomb panels of the two adjacent second impact-resistant members are connected to each other to communicate with their respective second cavities.

[0012] In one embodiment, the lower impact-resistant sound-absorbing component includes a third impact-resistant member, which includes at least two corrugated plates. One corrugated plate extends along a second direction, and the other corrugated plate extends along a third direction, with the crests of the two corrugated plates intersecting to form a single unit. The second direction and the third direction intersect to form a cross angle φ, and the cross angle φ is in the range of 60°≤φ≤120°.

[0013] In one embodiment, in the lower impact-resistant sound-absorbing assembly, the corrugated plates of two adjacent third impact-resistant members are stacked correspondingly.

[0014] Secondly, this application also provides a sound-absorbing device, including a plurality of sound-absorbing and impact-resistant superstructures as described in the first aspect, wherein the plurality of sound-absorbing and impact-resistant superstructures are arranged in parallel in a plane, and the cover edges of adjacent superstructures are in contact with each other.

[0015] Thirdly, this application also provides a method for preparing the sound-absorbing and impact-resistant superstructure as described in the first aspect, comprising the following steps: S100. Construct a three-dimensional model of the superstructure and import the data of the three-dimensional model into the laser selective melting printing equipment; S200: Set the laser scanning method and process parameters, and then use a laser selective melting printing equipment to print according to the process parameters to obtain a superstructure printing substrate; S300: The sample is separated from the printing substrate using a cutting process, and the sample components are subjected to processes including removing residual powder, heat treatment, cleaning and drying. After the processing is completed, a sound-absorbing and impact-resistant superstructure is obtained.

[0016] The technical solutions provided in this application have the following advantages compared with the prior art: Multiple impact-resistant components are assembled circumferentially along the sound-absorbing channel to form an impact-resistant layer. These layers are then stacked to form an impact-resistant unit, which is placed within the sound-absorbing channel of the sound-absorbing shell. This allows the sound-absorbing and impact-resistant superstructure to effectively absorb impact energy and reduce impact damage when subjected to impact. This achieves a balance between the superstructure's sound absorption and impact resistance performance, thus improving safety protection levels. Furthermore, the sound-absorbing and impact-resistant superstructure employs multiple impact-resistant sound-absorbing components stacked along a first direction. By adjusting the parameters of each component, it can absorb sound waves of different frequencies, significantly broadening the sound absorption band and meeting the needs of different frequency ranges and noise control. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] In the attached image: Figure 1 This is a schematic diagram of the sound-absorbing and impact-resistant superstructure of this application; Figure 2 This is a schematic diagram of the impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 3 This is a cross-sectional view of the sound-absorbing shell in a sound-absorbing and impact-resistant superstructure of this application; Figure 4 This is a structural schematic diagram of the upper impact-resistant component, the middle impact-resistant component, and the lower impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 5 This is a schematic diagram of the impact-resistant layer of the upper impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 6 This is a schematic diagram of the first impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 7 This is a front view of the first impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 8 This is a schematic diagram of the impact-resistant layer of the middle layer impact-resistant component of a sound-absorbing and impact-resistant superstructure according to this application; Figure 9 This is a schematic diagram of the second impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 10 This is a schematic diagram of the impact-resistant layer of the lower impact-resistant component of a sound-absorbing and impact-resistant superstructure according to this application; Figure 11 This is a schematic diagram of the third impact-resistant component in a sound-absorbing and impact-resistant superstructure of this application; Figure 12 This is a structural schematic diagram of a sound-absorbing device according to this application.

[0020] Icon labels: 10. Impact-resistant sound-absorbing component; 11. Sound-absorbing shell; 11a. Sound-absorbing cavity; 12. Cover plate; 12a. Channel; 13. Impact-resistant unit; 13a. First cavity; 131. Impact-resistant layer; 20. Upper impact-resistant sound-absorbing component; 21. First impact-resistant element; 21a. Vertical cell wall; 21b. Inclined cell wall; 30. Middle impact-resistant sound-absorbing component; 31. Second impact-resistant element; 31a. Honeycomb panel; 31b. Second cavity; 40. Lower impact-resistant sound-absorbing component; 41. Third impact-resistant element; 41a. Corrugated plate; X. First direction; Y. Second direction; Z. Third direction; B. First concave bending structure; C. Second bending structure; P. Second reference line; Q. First reference line. Detailed Implementation

[0021] To provide a clearer understanding of the technical features, objectives, and effects of this invention, specific embodiments are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the orientations or positional relationships indicated by terms such as "front," "rear," "upper," "lower," "left," "right," "longitudinal," "horizontal," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," and "tail" are based on the orientations or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific orientation. They are only for the convenience of describing this technical solution and do not indicate that the device or element referred to must have a specific orientation; therefore, they should not be construed as limitations on this invention.

[0022] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "linking," "fixing," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. When an component is referred to as being "on" or "below" another component, the component can be located "directly" or "indirectly" on the other component, or there may be one or more intermediary components. The terms "first," "second," "third," etc., are only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," "third," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0023] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0024] The following explains and describes the relevant technical terms involved in the embodiments of this application.

[0025] The first direction, second direction, and third direction defined in this embodiment are for the convenience of describing the positional relationship between components; specifically, the sound-absorbing shell can be used as a reference. The first direction, second direction, and third direction are mutually perpendicular. The first direction refers to the height direction of the sound-absorbing shell (refer to...). Figure 4 The X direction in the text refers to the direction of the sound-absorbing shell, and the second direction refers to the length direction of the sound-absorbing shell (refer to the X direction). Figure 4 The Y direction in the text refers to the width direction of the sound-absorbing shell (see reference). Figure 4 (in the Z direction).

[0026] Furthermore, in this embodiment, "multiple" refers to two or more, and the specific setting depends on actual needs.

[0027] Please refer to Figure 1 This application provides a sound-absorbing and impact-resistant superstructure, which includes multiple impact-resistant sound-absorbing components 10 stacked and fixedly connected along a first direction X. The impact-resistant sound-absorbing components 10 can be connected by methods including but not limited to adhesive bonding, thus achieving a seamless seal and eliminating gaps or holes that may be generated by mechanical connections such as bolts and rivets, while ensuring the structural strength of the sound-absorbing and impact-resistant superstructure; it can also be integrally printed using 3D printing.

[0028] Please refer to Figure 2 and Figure 3Specifically, each impact-resistant sound-absorbing component 10 includes a sound-absorbing shell 11 and a cover plate 12. The sound-absorbing shell 11 has a sound-absorbing channel 11a formed inside. The cover plate 12 is located on one side of the sound-absorbing shell 11 and covers an opening of the sound-absorbing channel 11a. The cover plate 12 has a hole 12a communicating with the sound-absorbing channel 11a. In other words, by defining a sound-absorbing channel 11a inside the sound-absorbing shell 11 and covering one opening of the sound-absorbing channel 11a with a cover plate 12, a semi-closed resonant sound-absorbing structure is formed. When sound waves are incident on the surface of the cover plate 12, the holes 12a on the cover plate 12 capture and guide the sound waves into the sound-absorbing channel 11a. When the frequency of the incident sound waves is close to the natural frequency of the sound-absorbing channel 11a and the holes 12a, strong vibrations will occur in the holes 12a, causing air molecules to collide with the inner wall of the holes 12a due to vibration, so as to convert some of the sound energy into heat and dissipate it. The sound waves entering the sound-absorbing channel 11a will be reflected and superimposed between its inner walls, so that the air in the sound-absorbing channel 11a is repeatedly compressed and expanded due to vibration, and then the sound energy is further consumed by the viscous resistance of the air, thereby achieving the sound absorption effect.

[0029] In addition, after the cover plate 12 covers the opening of the sound absorption channel 11a, it can effectively block external impurities such as dust, moisture, and particulate matter from entering the channel, and prevent impurities from adhering to the channel wall or the subsequent impact-resistant unit 13, thereby ensuring the long-term stability of the acoustic characteristics (such as volume and inner wall friction coefficient) of the sound absorption channel 11a and the structural integrity of the impact-resistant unit 13.

[0030] However, underwater sound-absorbing structures, due to insufficient impact resistance and durability, are prone to stress concentration when subjected to water flow or sound wave impacts, leading to localized structural damage and affecting sound absorption performance. Therefore, please refer to... Figure 2 and Figure 3 In one embodiment, each impact-resistant sound-absorbing component 10 further includes an impact-resistant unit 13 disposed within the sound-absorbing channel 11a. The impact-resistant unit 13 has a first cavity 13a extending along a first direction X. The impact-resistant unit 13 includes multiple impact-resistant layers 131 stacked along the first direction X. Each impact-resistant layer 131 has a through hole in its center. One impact-resistant layer 131 near the cover plate 12 abuts against the cover plate 12. The through holes of the multiple stacked impact-resistant layers 131 coaxially connect to form the first cavity 13a. The projection of the hole 12a within the first cavity 13a is located on the central axis of the first cavity 13a.

[0031] In other words, multiple impact-resistant layers 131 are stacked along the first direction X to form an impact-resistant unit 13, which is then placed in the sound-absorbing channel 11a. When an external impact occurs, the impact energy is first received by the impact-resistant layer 131 near the cover plate 12, and then the energy is initially dissipated through its deformation (such as elastic compression, local bending, etc.). The remaining impact energy is then transferred to the next impact-resistant layer 131 for dissipation. In this way, the impact energy is dissipated in layers, which can significantly reduce the load intensity of a single impact on a single structure, avoid the overall structure from breaking or deforming due to instantaneous overload, and effectively enhance the impact resistance of the sound-absorbing and impact-resistant superstructure.

[0032] It should be noted that because the projection of the perforation is located on the central axis of the first cavity 13a, the sound waves, after entering the sound-absorbing channel 11a through the perforation, will propagate directly along the central axis of the first cavity 13a. This reduces the premature collision between the sound waves and the inner wall of the impact-resistant layer 131, allowing the sound waves more time to dissipate energy through resonance, friction, and reflection from the channel wall, thus achieving a better sound absorption effect. If the projection of the perforation within the first cavity 13a is offset, the sound waves may directly impact the joints of the impact-resistant layer 131 or the edge of a certain impact-resistant component. On the one hand, this will reduce the sound absorption efficiency due to impact reflection; on the other hand, long-term sound wave vibration may exacerbate fatigue damage to the impact-resistant component.

[0033] Furthermore, each impact-resistant layer 131 includes multiple impact-resistant components, which are assembled together circumferentially along the sound-absorbing channel 11a to form a single unit. The through-hole is formed by assembling multiple impact-resistant components circumferentially along the sound-absorbing channel 11a. This allows localized impact stress to be evenly distributed circumferentially across the multiple impact-resistant components. For example, when the impact load is biased towards one side of the first cavity 13a, the impact-resistant component on that side will transfer the stress to adjacent components. The load is balanced through the interaction of the splicing surfaces, preventing a single impact-resistant component from cracking or detaching due to stress concentration, thus improving the overall stability of the impact-resistant layer 131.

[0034] Furthermore, when multiple impact-resistant layers 131 are stacked, tiny gaps inevitably exist between the layers; at the same time, the circumferential splicing of the impact-resistant components also forms minute gaps. Due to the existence of these gaps and gaps, a viscous friction effect can be generated on mid-to-high frequency sound waves, causing air molecules to vibrate violently in the gaps when the sound waves pass through. This allows the molecular components to collide and rub against the wall, converting sound energy into heat energy, which is beneficial to improving the sound absorption effect.

[0035] In summary, the sound-absorbing and impact-resistant superstructure of this application utilizes multiple impact-resistant components assembled circumferentially along the sound-absorbing channel 11a to form an impact-resistant layer 131. These multiple impact-resistant layers 131 are then stacked to form an impact-resistant unit 13, which is subsequently placed within the sound-absorbing channel 11a of the sound-absorbing shell 11. This allows the sound-absorbing and impact-resistant superstructure to effectively absorb impact energy and reduce impact damage when subjected to impact, achieving a balance between sound absorption and impact resistance, thus improving safety protection levels. Furthermore, the sound-absorbing and impact-resistant superstructure employs multiple impact-resistant sound-absorbing components 10 stacked along the first direction X. By adjusting the design parameters of each impact-resistant sound-absorbing component 10, it is possible to absorb sound waves of different frequencies, thereby significantly broadening the sound absorption band and meeting the needs of different frequency ranges and noise control.

[0036] To facilitate understanding of the working principle of the sound-absorbing and impact-resistant superstructure of this application, the following example uses three sound-absorbing components stacked and connected together as an example, but it is not limited to this.

[0037] Please refer to Figure 4 The impact-resistant sound-absorbing component 10 comprises at least three layers, namely an upper impact-resistant sound-absorbing component 20, a middle impact-resistant sound-absorbing component 30, and a lower impact-resistant sound-absorbing component 40, which are sequentially stacked and fixedly connected along the first direction X. Taking the upper impact-resistant sound-absorbing component 20 absorbing mid-to-high frequency sound waves, the middle impact-resistant sound-absorbing component 30 absorbing mid-to-low frequency sound waves, and the lower impact-resistant sound-absorbing component 40 absorbing low frequency sound waves as an example, when a sound wave is incident on the upper impact-resistant sound-absorbing component 20, it absorbs the mid-to-high frequency sound waves. Then, the middle impact-resistant sound-absorbing component 30 absorbs the mid-to-low frequency sound waves, and finally, the lower impact-resistant sound-absorbing component 40 absorbs the low-frequency sound waves that were not absorbed by the middle impact-resistant sound-absorbing component 30. Through optimized design of the material parameters and structural dimensions of each layer of components, multiple reflections, scattering, and internal losses occur at the interface of the sound waves, further improving the sound absorption efficiency. Meanwhile, the interlayer connection has certain damping characteristics, which helps to dissipate impact energy and takes into account both sound absorption and impact resistance.

[0038] The sound absorption channels 11a of the upper, middle, and lower impact-absorbing sound-absorbing components 20, 30, and 40 gradually increase in depth along the first direction X. Specifically, the upper impact-absorbing component 20 has the smallest sound absorption channel 11a, concentrating its resonant frequency in the mid-to-high frequency range; the lower impact-absorbing component 40 has the largest sound absorption channel 11a, focusing its resonant frequency in the low-frequency range; and the middle impact-absorbing component 30 has a sound absorption channel 11a with a depth between the two, covering the mid-to-low frequency transition range and filling the gap in sound absorption bands between the upper and lower layers. This creates a continuous sound absorption gradient of mid-to-high frequency, mid-to-low frequency, and low frequency, completely overcoming the limitation of traditional single-depth channels that can only absorb narrow-band noise.

[0039] Meanwhile, the impact stiffness of the impact-resistant units 13 in the upper impact-resistant sound-absorbing component 20, the middle impact-resistant sound-absorbing component 30, and the lower impact-resistant sound-absorbing component 40 gradually increases. That is to say, the impact-resistant unit 13 of the upper impact-resistant sound-absorbing component 20 has the lowest stiffness. When an external impact occurs, the upper layer can quickly absorb the peak impact energy through greater elastic deformation, significantly reducing the impact intensity transmitted to the middle layer and preventing subsequent layers from being overloaded. After being buffered by the upper and middle impact-absorbing components, the remaining impact energy has been greatly reduced. Since the impact-resistant unit 13 of the lower impact-resistant sound-absorbing component 40 has the highest stiffness, it can use its high stiffness to resist deformation, ensuring that the superstructure as a whole will not be punctured or permanently deformed. The stiffness of the middle layer is between the two, which can bear the impact energy transmitted from the upper layer and further dissipate it, while avoiding abrupt changes in stiffness, so that the impact energy will form stress concentration between the layers.

[0040] Please refer to Figures 5 to 7 In one embodiment, the upper impact-resistant sound-absorbing component 20 includes a first impact-resistant member 21, which is a concave negative Poisson's ratio metamaterial cell. The concave negative Poisson's ratio metamaterial cell has a first reference line Q and a second reference line P that pass through its center and are perpendicular to each other. The first reference line Q and the second reference line P are defined here for the convenience of describing the structure of the concave negative Poisson's ratio metamaterial cell and do not serve a limiting function.

[0041] The concave negative Poisson's ratio metamaterial cell includes two vertical cell walls 21a and four inclined cell walls 21b. The two vertical cell walls 21a are symmetrically distributed at intervals along a first reference axis, and the four inclined cell walls 21b are located within the space defined by the two vertical cell walls 21a. The two inclined cell walls 21b are connected at their closest ends to form a first concave bending structure B, and their far ends are connected to the upper ends of the two vertical cell walls 21a respectively. The other two inclined cell walls 21b are connected at their closest ends to form a second concave bending structure, and their far ends are connected to the lower ends of the two vertical cell walls 21a respectively. The first concave bending structure B and the second concave bending structure are symmetrical about a second reference line P.

[0042] In practical applications, when the upper impact-resistant sound-absorbing component 20 is subjected to a load in the first direction X, the impact load is first transmitted to the first concave bending structure B. At this time, the two inclined cell walls 21b are subjected to force, causing them to begin to rotate slightly around the connection point with the vertical cell wall 21a, and then gradually unfold from the original V-shape. At the same time, under the force transmission of the vertical cell wall 21a, the two inclined cell walls 21b at the lower end also unfold synchronously. The two symmetrical vertical cell walls 21a are subjected to load and begin to contract towards the center along the second reference line P. After the impact energy reaches its peak, the inclined cell walls 21b unfold to the maximum angle (close to a straight state), and the two vertical cell walls 21a contract to the minimum distance. At this time, the compression of the cell in the first reference line Q direction reaches the maximum, and the contraction in the second reference line P direction reaches the maximum, thus having better impact resistance. In other words, the first impact-resistant component 21 adopts a concave negative Poisson's ratio metamaterial cell, which not only has good resilience, but also can deform and recover quickly during the impact of load, so as to effectively absorb impact energy and enhance the impact resistance of the metastructure.

[0043] Furthermore, within the same impact-resistant layer 131 of the upper impact-resistant sound-absorbing component 20, the vertical cell walls 21a of two adjacent first impact-resistant members 21 are bonded together. That is, when the impact-resistant layer 131 is impacted, the force generated by the lateral contraction of a single cell is transmitted to adjacent cells through the bonded vertical cell walls 21a, thus preventing localized stress accumulation caused by the individual contraction of a single cell. Simultaneously, the bonded vertical cell walls 21a also form a continuous support surface, thereby enhancing the overall resistance of the impact-resistant layer 131 to lateral deformation and preventing the impact-resistant layer 131 from tilting when impacted.

[0044] And / or, the end faces of the four inclined cell walls 21b of two adjacent first impact-resistant members 21 are connected, so that the impact energy can be transferred from the stressed cell to the surrounding cells. For example, when the inclined cell wall 21b of a certain cell is impacted and unfolds, the connected end faces will distribute some of the energy to the inclined cell walls 21b of the adjacent cells, so that multiple cells can share the impact load and avoid the single cell from breaking due to energy concentration.

[0045] Furthermore, during the impact process, individual cells may tend to move away from their original positions due to the force. In this embodiment, the vertical cell wall 21a and the inclined cell wall 21b that are attached together will form a mutual locking constraint to limit the displacement of the cells and ensure that all cells always remain in the preset position of the impact-resistant layer 131, so as to avoid the structural loosening of the impact-resistant layer 131 due to cell misalignment.

[0046] In one embodiment, the distance between the first concave bending structure B and the second bending structure along the extension direction of the second reference line P is H, and they satisfy the following relationship: 1 / 3≤H / L≤2 / 3 Where L is the length of the vertical cell wall 21a.

[0047] In this embodiment, the distance between the first concave bending structure B and the second bending structure along the second reference line P is limited to the above-mentioned range to ensure that the length of the inclined cell wall 21b is moderate. During deformation, the inclined cell wall 21b can fully expand to efficiently absorb impact energy and avoid local stress concentration. If H / L < 1 / 3, the two concave bending structures will be too close, the length of the inclined cell wall 21b will be insufficient, the expansion space during deformation will be limited, and the impact energy cannot be dissipated through sufficient elastic deformation, which will easily lead to the impact load being concentrated on the local cell wall and causing fracture. If H / L > 2 / 3, the inclined cell wall 21b will be too long, the stress distribution during deformation will be uneven, which will easily cause the inclined cell wall 21b to bend or fracture, resulting in insufficient overall stiffness of the impact-resistant layer 131.

[0048] Please refer to Figure 8 and Figure 9 In one embodiment, the middle-layer impact-resistant sound-absorbing component 30 includes a second impact-resistant member 31, which has a second cavity 31b extending along a first direction X. The second impact-resistant member 31 includes multiple honeycomb panels 31a, which are sequentially connected to form a regular hexagonal honeycomb structure. This structure allows for the uniform diffusion of localized impact loads along the honeycomb walls to the surrounding area under impact, thereby eliminating localized stress concentration and ensuring that the middle-layer impact-resistant sound-absorbing component 30 does not experience localized cracking or overall collapse under impact. Furthermore, after sound waves are transmitted to the sound-absorbing cavity of the middle-layer impact-resistant sound-absorbing component 30, mid-to-low frequency sound waves resonate within the second cavity 31b of the honeycomb structure. The sound waves collide with the honeycomb panels 31a, converting sound energy into heat energy, further enhancing sound energy dissipation and preventing mid-to-low frequency sound waves from penetrating the middle-layer impact-resistant sound-absorbing component 30 and transmitting to the lower-layer impact-resistant sound-absorbing component 40.

[0049] Furthermore, within the same impact-resistant layer 131 of the middle-layer impact-resistant sound-absorbing component 30, the surfaces of the honeycomb panels 31a of two adjacent second impact-resistant components 31 are bonded together. This means that when an impact load is applied to a honeycomb panel 31a, it is quickly transferred to the surrounding honeycomb panels 31a through the bonding surface, preventing premature collapse of individual honeycomb units due to localized overload. Simultaneously, the bonded honeycomb panels 31a support each other, enhancing the overall lateral deformation resistance of the impact-resistant layer 131 and ensuring the smooth transmission of impact loads along the first direction X.

[0050] And / or, in two adjacent impact-resistant layers 131 of the middle layer impact-resistant sound-absorbing component 30, the end faces of the honeycomb panels 31a of two adjacent second impact-resistant members 31 are connected to each other to connect their respective second cavities 31b. In this way, after the impact-resistant layers 131 are stacked along the first direction X, a continuous acoustic channel along the first direction X can be formed, so that the mid-low frequency sound waves transmitted to the middle layer impact-resistant sound-absorbing component 30 can propagate layer by layer along the continuous cavity, prolonging the residence time of sound energy in the middle layer, and fully dissipating energy through air molecule collisions and friction with the honeycomb panels 31a, further improving the sound absorption effect.

[0051] Please refer to Figure 10 and Figure 11 In one embodiment, the lower impact-resistant sound-absorbing component 40 includes a third impact-resistant member 41, which comprises at least two corrugated plates 41a. One corrugated plate 41a extends along a second direction Y, and the other corrugated plate 41a extends along a third direction Z. The crests of the two corrugated plates 41a intersect to form a single unit. The intersection of the second direction Y and the third direction Z forms a crossing angle φ, the range of which is 60°≤φ≤120°.

[0052] In other words, the third impact-resistant component 41 uses two corrugated plates 41a extending along the second and third third directions Z respectively, with their crests intersecting to form a single unit. This allows the impact load to be simultaneously distributed along the second and third third directions Z and the intersection direction. For example, when an impact acts along the first direction X, the load will be transferred through the intersecting crests to multiple troughs and crests of the two corrugated plates 41a, where it is jointly borne by the crest-trough structure of the corrugated plates, thus avoiding local stress concentration. At the same time, if the intersection angle φ < 60°, the two corrugated plates 41a are too close together, resulting in redundant stiffness in one direction and insufficient stiffness in another, making it impossible to evenly distribute multi-directional loads. If the intersection angle φ > 120°, the included angle between the two corrugated plates is too large, reducing the effective area at the intersection of the crests, making it easy for the crests to detach or break due to impact. Therefore, this embodiment limits the cross angle φ to the above range, which can simultaneously enhance the impact stiffness of the second and third directions Z, so that the lower impact-resistant sound-absorbing component 40 remains stable under impact, and avoids the structure being penetrated due to insufficient stiffness in a certain direction.

[0053] Furthermore, in the lower-layer impact-resistant sound-absorbing assembly, the corrugated plates of two adjacent third impact-resistant components are stacked with corresponding crests and corresponding troughs. That is, the corresponding stacking of crests and troughs creates a continuous stress transmission band at the contact interface of adjacent corrugated plates along the corrugation extension direction (e.g., circumferential direction). This allows the stress generated by the impact to diffuse evenly along the top and sides of the crests and the bottom and sides of the troughs, rather than being confined to isolated contact points. For example, when an impact load acts on the crest region, the stress is transmitted to the trough regions on both sides through the aligned crests, and further dispersed by the continuous structure of the troughs, preventing tearing or deformation of the corrugated plates due to excessive local stress.

[0054] Please refer to Figure 12 Secondly, this application also provides a sound-absorbing device, including a plurality of sound-absorbing and impact-resistant superstructures as described in the above embodiments. The plurality of sound-absorbing and impact-resistant structures are arranged in parallel in a plane, and the edges of the cover plates 12 of adjacent superstructures are in contact with each other.

[0055] Because the single superstructure in the above embodiments has a wide-band sound absorption capability and strong impact resistance, the sound absorption device formed by arranging multiple sound-absorbing and impact-resistant superstructures in parallel will simultaneously have good sound absorption performance and enhanced impact resistance. This not only optimizes the sound absorption efficiency, but also makes it highly scalable in practical engineering applications, enabling it to perform excellent sound absorption in multiple different acoustic environments and meet the needs of different frequency ranges and noise control.

[0056] Thirdly, this application also provides a method for preparing a sound-absorbing and impact-resistant superstructure, comprising the following steps: S100. Construct a three-dimensional model of the superstructure and import the data of the three-dimensional model into the laser selective melting printing equipment; S200: Set the laser scanning method and process parameters, and then use a laser selective melting printing equipment to print according to the process parameters to obtain a superstructure printing substrate; S300: The sample is separated from the printing substrate using a cutting process, and the sample components are subjected to processes including removing residual powder, heat treatment, cleaning and drying. After the processing is completed, a sound-absorbing and impact-resistant superstructure is obtained.

[0057] For example, the above-mentioned process for removing residual powder can be carried out by using high-pressure airflow (approximately 3-5 bar), brushing, or vibration (vibration frequency 20-30 Hz) to remove the powder, thereby cleaning up the residual powder for subsequent processing. Furthermore, it should be noted that the specific steps of removing residual powder, heat treatment, cleaning, and drying in this embodiment are prior art and will not be elaborated upon.

[0058] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made with respect to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A sound-absorbing and impact-resistant superstructure, characterized in that, It includes a plurality of impact-resistant sound-absorbing components that are stacked and fixedly connected along a first direction, the impact-resistant sound-absorbing components including: The sound-absorbing shell has sound-absorbing channels inside. A cover plate, located on one side of the sound-absorbing shell, covers an opening of the sound-absorbing channel, and the cover plate has a channel communicating with the sound-absorbing channel; An impact-resistant unit is disposed within the sound-absorbing channel, the impact-resistant unit having a first cavity extending along the first direction; The impact-resistant unit includes multiple impact-resistant layers stacked along the first direction. Each impact-resistant layer has a through hole in its center. One impact-resistant layer near the cover plate abuts against the cover plate. The through holes of the multiple stacked impact-resistant layers are coaxially connected to form the first cavity. The projection of the cavity in the first cavity is located on the central axis of the first cavity. Each of the impact-resistant layers includes multiple impact-resistant components, which are assembled together in a single unit along the circumference of the sound-absorbing channel. The through-hole is formed by assembling multiple impact-resistant components along the circumference of the sound-absorbing channel.

2. The sound-absorbing and impact-resistant superstructure according to claim 2, characterized in that, The impact-resistant sound-absorbing component is provided in at least three layers, namely an upper impact-resistant sound-absorbing component, a middle impact-resistant sound-absorbing component, and a lower impact-resistant sound-absorbing component that are stacked and fixedly connected in sequence along the first direction. The sound absorption channels of the upper impact-resistant sound absorption component, the middle impact-resistant sound absorption component, and the lower impact-resistant sound absorption component gradually increase in depth along the first direction, and the impact stiffness of the impact-resistant unit gradually increases.

3. The sound-absorbing and impact-resistant superstructure according to claim 2, characterized in that, The upper impact-resistant sound-absorbing component includes a first impact-resistant element, which is a concave negative Poisson's ratio metamaterial cell. The concave negative Poisson's ratio metamaterial cell has a first reference line and a second reference line that pass through its center and are perpendicular to each other. The concave negative Poisson's ratio metamaterial cell includes two vertical cell walls and four inclined cell walls. The two vertical cell walls are symmetrically distributed at intervals around the first reference axis, and the four inclined cell walls are located within the space defined by the two vertical cell walls. The two inclined cell walls are connected at their closest ends to form a first concave bending structure, and their far ends are respectively connected to the upper ends of the two vertical cell walls. The other two inclined cell walls are connected at their closest ends to form a second concave bending structure, and their far ends are respectively connected to the lower ends of the two vertical cell walls. The first concave bending structure and the second concave bending structure are symmetrical about the second reference line.

4. The sound-absorbing and impact-resistant superstructure according to claim 3, characterized in that, In the same impact-resistant layer of the upper impact-resistant sound-absorbing component, the vertical cell walls of two adjacent first impact-resistant members are in contact with each other; and / or, the end faces of the four inclined cell walls of two adjacent first impact-resistant members are in contact.

5. The sound-absorbing and impact-resistant superstructure according to claim 3, characterized in that, The distance H between the first concave bending structure and the second bending structure along the extension direction of the second reference line satisfies the following relationship: in, The length of the vertical cell wall is given.

6. The sound-absorbing and impact-resistant superstructure according to claim 3, characterized in that, The middle layer impact-resistant sound-absorbing component includes the second impact-resistant member, the second impact-resistant member having a second cavity extending along the first direction; The second impact-resistant component includes multiple honeycomb panels, which are connected in sequence to form a regular hexagonal honeycomb structure.

7. The sound-absorbing and impact-resistant superstructure according to claim 6, characterized in that, In the same impact-resistant layer of the middle-layer impact-resistant sound-absorbing assembly, the surfaces of the honeycomb panels of two adjacent second impact-resistant members are bonded to each other; and / or, In the two adjacent impact-resistant layers of the middle impact-resistant sound-absorbing assembly, the end faces of the honeycomb panels of the two adjacent second impact-resistant members are connected to each other to communicate with their respective second cavities.

8. The sound-absorbing and impact-resistant superstructure according to claim 3, characterized in that, The lower impact-resistant sound-absorbing component includes a third impact-resistant member, which includes at least two corrugated plates. One corrugated plate extends along a second direction, and the other corrugated plate extends along a third direction. The crests of the two corrugated plates intersect to form a single unit. The second direction and the third direction intersect to form a cross angle φ, and the cross angle φ is in the range of 60°≤φ≤120°.

9. The sound-absorbing and sound-resistant superstructure according to claim 8, characterized in that, In the lower layer of the impact-resistant sound-absorbing assembly, the corrugated plates of two adjacent third impact-resistant components are stacked in a corresponding manner.

10. A sound-absorbing device, characterized in that, It includes a plurality of sound-absorbing and impact-resistant superstructures as described in any one of claims 1 to 9, wherein the plurality of sound-absorbing and impact-resistant structures are arranged in parallel in a plane, and the cover edges of adjacent superstructures are in contact with each other.

11. A method for preparing a sound-absorbing and impact-resistant metastructure as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S100. Construct a three-dimensional model of the superstructure and import the data of the three-dimensional model into the laser selective melting printing equipment; S200: Set the laser scanning method and process parameters, and then use a laser selective melting printing equipment to print according to the process parameters to obtain a superstructure printing substrate; S300: The sample is separated from the printing substrate using a cutting process, and the sample components are subjected to processes including removing residual powder, heat treatment, cleaning and drying. After the processing is completed, a sound-absorbing and impact-resistant superstructure is obtained.

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