Vibration absorption unit and vibration absorption device with three-dimensional negative poisson ratio effect

Abstract

The invention relates to a vibration absorption unit with a three-dimensional negative Poisson's ratio effect and a vibration absorption device, and relates to the technical field of vibration reduction devices. The vibration absorption unit comprises a metal frame and a vibration absorption unit, wherein the metal frame has a three-dimensional negative Poisson's ratio effect; the elastic piece is arranged in the metal frame, and the elastic piece is connected with the inner wall of the metal frame; the load block is arranged in the metal frame, and the load block is connected with the elastic piece; and the fixing piece is connected with the elastic piece and the load block. The vibration absorption unit provided by the invention overcomes the defect that a traditional two-dimensional negative Poisson's ratio honeycomb structure only presents a negative Poisson's ratio effect in a single dimension, and is suitable for a multi-axis loading condition. Meanwhile, the metal frame is combined with the elastic piece and the load block in the metal frame, so that the vibration reduction effect at a specified frequency point can be achieved, the phenomenon that the low-frequency vibration line spectrum is prominent can be avoided, and when the external excitation frequency is close to the inherent frequency of the vibrator system, the energy of elastic waves is greatly absorbed; therefore, the propagation of elastic waves in the vibration absorption unit and the vibration absorption device is isolated.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration reduction devices, and in particular to a vibration absorption unit and a vibration absorption device with a three-dimensional negative Poisson's ratio effect. Background Art

[0002] The control of noise and vibration transmission of mechanical equipment is an important link that cannot be ignored in all industries. In order to attenuate the additional vibration hazards brought by mechanical equipment while completing functional work. Traditional vibration reduction methods mostly use the elastic installation method of equipment. Whether it is single-layer, double-layer or floating raft, it is passive vibration isolation, and the effect of low-frequency vibration isolation is very limited. If the disturbance frequency band of the mechanical equipment is low, the stiffness of the vibration isolator needs to be designed to be extremely small, and it is difficult to achieve both vibration absorption effect and system stability. Double-layer and floating raft vibration isolation systems have better vibration reduction effects, but the necessary mass must be achieved. It is usually required that the ratio of intermediate mass to equipment mass is greater than 0.5, and providing too much intermediate mass will inevitably bring resource and economic burdens.

[0003] Analyzing the existing vibration reduction methods, if we want to further improve the vibration reduction performance of the structure itself, this type of structure first needs to have the ability to efficiently isolate or absorb external energy, and have a certain inhibitory effect on the transmission of low-frequency vibrations; secondly, this type of structure has the characteristics of lightweight, and at the same time has a certain strength and rigidity, and can play a load-bearing role.

[0004] Under the constraints of the above requirements, honeycomb structures with negative Poisson's ratio effect are ideal design carriers. Honeycomb structures have porous characteristics and can use their load-bearing capacity to absorb energy. At the same time, through multi-scale mechanical design, the honeycomb structure can exhibit a macroscopic negative Poisson's ratio effect. Unlike positive Poisson's ratio materials that expand laterally when compressed longitudinally, negative Poisson's ratio materials shrink laterally at the same time after being compressed longitudinally. This phenomenon gives it excellent energy absorption capacity. The structural form of negative Poisson's ratio honeycombs gives it great superiority and potential in resisting vibration impact loads.

[0005] However, traditional negative Poisson's ratio honeycomb structures are mostly two-dimensional, and they only show the negative Poisson's ratio phenomenon within the plane, that is, they can only show their special properties in a single dimension. However, mechanical equipment is often in complex working conditions, and materials with two-dimensional negative Poisson's ratio effect cannot have consistent performance in multiple directions, and cannot meet the multi-directional performance requirements of mechanical equipment under complex working conditions.

[0006] Therefore, how to propose a vibration reduction structure that can achieve both vibration absorption effect and system stability and has consistent multi-directional performance has become a technical problem that needs to be solved urgently. Summary of the invention

[0007] In view of this, the present invention aims to solve the problems of large intermediate mass, poor low-frequency vibration isolation effect, inability of the vibration absorption structure to meet multi-directional performance consistency, and inability to be applied to complex working environments in traditional passive vibration isolation.

[0008] Specifically, the present invention is achieved through the following technical solutions:

[0009] According to a first aspect of the present invention, a vibration absorbing unit having a three-dimensional negative Poisson's ratio effect is provided, comprising: a metal frame having a three-dimensional negative Poisson's ratio effect; an elastic member disposed in the metal frame and connected to an inner wall of the metal frame; a load block disposed in the metal frame and connected to the elastic member; and a fixing member connecting the elastic member and the load block.

[0010] Optionally, in some technical solutions, the metal frame includes: a top wall; a side wall, one end of which is connected to the top wall; a bottom wall, which is arranged opposite to the top wall and connected to the other end of the side wall; wherein the side wall is recessed toward the interior of the metal frame, the side wall is connected to an elastic member, and the elastic member can be snapped into the metal frame.

[0011] Optionally, in some technical solutions, the top wall includes two cross-arranged top wall plates, the bottom wall includes two cross-arranged bottom wall plates, two ends of the side wall are respectively connected to one end of the top wall plate and one end of the bottom wall plate, and the size of the bottom wall plate is the same as that of the top wall plate; the two ends of the side wall are inclined toward the inside of the metal frame along the height direction of the metal frame, and the height of the metal frame is expressed as:

[0012]

[0013] Wherein, d represents the height of the metal frame, H represents the length of the top wall plate and / or the bottom wall plate, and θ represents the concave angle of the side wall.

[0014] Optionally, in some technical solutions, the elastic member includes two cross-arranged elastic strips, along the length direction of the elastic strips, the end faces of the two elastic strips are both concave inwards, the concave angle of the elastic strips is the same as the inclination angle of the side wall, and the length of the elastic member is expressed as:

[0015]

[0016] Wherein, Y represents the length of the elastic strip, H represents the length of the top wall plate and / or the bottom wall plate, L represents the distance from one end of the side wall to the angle turning point, θ represents the concave angle of the elastic strip, and N represents the width of the elastic strip.

[0017] Optionally, in some technical solutions, the load block is in the shape of a cylinder, a second through hole is provided at the center of the load block, and the mass of the load block is expressed as:

[0018] M=(1 / 2πR2 -1 / 2πr 2 )kρ;

[0019] Wherein, M represents the mass of the load block, π represents the pi, R represents the radius of the load block, r represents the radius of the second through hole, k represents the thickness of the load block, and ρ represents the material density of the load block.

[0020] Optionally, in some technical solutions, a first through hole is provided at the center of the elastic member, a second through hole is provided at the center of the load block, the fixing member includes a stud bolt and a fastening nut, the stud bolt is provided in the first through hole and the second through hole, and the fastening nut can fix the load block on the elastic member.

[0021] Optionally, in some technical solutions, the vibration absorbing unit with three-dimensional negative Poisson's ratio effect also includes: an adhesion layer, located in the first through hole, connecting the elastic member and the stud bolt; wherein the adhesion layer can fix the stud bolt in the first through hole.

[0022] According to a second aspect of the present invention, a vibration absorbing device with a three-dimensional negative Poisson's ratio effect is provided, comprising the vibration absorbing unit with a three-dimensional negative Poisson's ratio effect as proposed in the first aspect.

[0023] Optionally, in some technical schemes, the number of vibration absorbing units includes multiple, and the multiple vibration absorbing units are arranged in arrays along the x-axis, y-axis and z-axis directions, and every two vibration absorbing units on the z-axis share a top wall or a bottom wall of a metal frame; wherein, the array number n1 on the z-axis is the number of honeycomb layers, the array number on the x-axis is n2, and the array number on the y-axis is n3, the number of vibration absorbing units in a single layer of honeycomb is n2×n3, and the number of vibration absorbing units in each layer of honeycomb is the same.

[0024] Optionally, in some technical solutions, the number of the vibration absorbing units includes multiple, and any vibration absorbing unit shares a side wall of a metal frame with two adjacent vibration absorbing units.

[0025] The technical solution provided by the present invention brings at least the following beneficial effects:

[0026] The present invention provides a vibration absorbing unit and a vibration absorbing device with a three-dimensional negative Poisson's ratio effect. The vibration absorbing unit and the vibration absorbing device are both honeycomb structures and are based on a three-dimensional negative Poisson's ratio honeycomb cell. The three-dimensional negative Poisson's ratio honeycomb cell is also a metal frame. An elastic member, a load block and a fixing member are arranged in the metal frame. The fixing member fixes the load block on the elastic member, so that the fixing member, the elastic member and the load block form an oscillator system. The vibration absorbing unit and the vibration absorbing device proposed by the present invention have excellent mechanical properties such as light weight, high specific modulus, high specific strength and high energy absorption, and overcome the defect that the traditional two-dimensional negative Poisson's ratio honeycomb structure only presents the negative Poisson's ratio effect in a single dimension, so that the vibration absorbing unit and the vibration absorbing device have higher isotropic consistency and are suitable for multi-axial loading. At the same time, the combination of the metal frame and the elastic member and the load block inside it can achieve the effect of vibration reduction at a specified frequency point, and can eliminate the phenomenon of prominent low-frequency vibration line spectrum. When the external excitation frequency is close to the natural frequency of the oscillator system, the energy of the elastic wave is greatly absorbed, thereby isolating the propagation of the elastic wave in the vibration absorbing unit and the vibration absorbing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0029] Figure 1 One of the structural schematic diagrams of a vibration absorbing unit with a three-dimensional negative Poisson's ratio effect provided by an embodiment of the present invention;

[0030] Figure 2 A second structural schematic diagram of a vibration absorbing unit with a three-dimensional negative Poisson's ratio effect provided by an embodiment of the present invention;

[0031] Figure 3 A third structural schematic diagram of a vibration absorbing unit with a three-dimensional negative Poisson's ratio effect provided by an embodiment of the present invention;

[0032] Figure 4 One of the structural schematic diagrams of a metal frame provided by an embodiment of the present invention;

[0033] Figure 5 A second structural schematic diagram of a metal frame provided in an embodiment of the present invention;

[0034] Figure 6 A third structural schematic diagram of a metal frame provided in an embodiment of the present invention;

[0035] Figure 7 A fourth structural schematic diagram of a metal frame provided in an embodiment of the present invention;

[0036] Figure 8 One of the structural schematic diagrams of an oscillator system provided by an embodiment of the present invention;

[0037] Fig. 9 A second structural schematic diagram of an oscillator system provided by an embodiment of the present invention;

[0038] Fig.10 A third structural schematic diagram of an oscillator system provided by an embodiment of the present invention;

[0039] Fig.11 A schematic diagram of the structure of a load block provided by an embodiment of the present invention;

[0040] Fig.12 A fourth structural schematic diagram of an oscillator system provided by an embodiment of the present invention;

[0041] Fig.13 A schematic diagram of the structure of an elastic member provided by an embodiment of the present invention;

[0042] Fig.14 One of the structural schematic diagrams of a vibration absorbing device with a three-dimensional negative Poisson's ratio effect provided by an embodiment of the present invention;

[0043] Fig.15 A second structural schematic diagram of a vibration absorbing device with a three-dimensional negative Poisson's ratio effect provided by an embodiment of the present invention;

[0044] Fig.16 A schematic diagram of the structure of a simplified power model provided in an embodiment of the present invention.

[0045] Figures 1 to 16 The corresponding relationship between the reference numerals and the component names is as follows:

[0046] 1 vibration absorbing unit, 11 metal frame, 111 top wall, 1111 top wall plate, 112 side wall, 113 bottom wall, 1131 bottom wall plate, 12 elastic member, 121 elastic strip, 122 first through hole, 13 load block, 131 second through hole, 14 fixing member, 141 stud bolt, 142 fastening nut, 15 adhesive layer, 16 weight, 17 damper, 18 spring, 2 vibration absorbing device. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] According to a first aspect of the present invention, a vibration absorbing unit 1 having a three-dimensional negative Poisson's ratio effect is provided. Figure 1 , Figure 2 and Figure 3 As shown, the vibration absorbing unit 1 includes: a metal frame 11, the metal frame 11 has a three-dimensional negative Poisson's ratio effect; an elastic member 12, which is arranged in the metal frame 11 and connected to the inner wall of the metal frame 11; a load block 13, which is arranged in the metal frame 11 and connected to the elastic member 12; and a fixing member 14, which connects the elastic member 12 and the load block 13.

[0049] The vibration absorbing unit 1 with three-dimensional negative Poisson's ratio effect provided by the present invention comprises a metal frame 11, an elastic member 12, a load block 13 and a fixing member 14. Among them, the metal frame 11 has a three-dimensional negative Poisson's ratio effect. In fact, the metal frame 11 is a three-dimensional negative Poisson's ratio honeycomb cell, in which an elastic member 12, a load block 13 and a fixing member 14 are arranged. The fixing member 14 fixes the load block 13 on the elastic member 12, so that the load block 13 and the elastic member 12 form an oscillator system, and then when the external vibration occurs, the vibration absorbing unit 1 can absorb the external vibration energy. The vibration absorbing unit 1 proposed by the present invention has excellent mechanical properties such as light weight, high specific modulus, high specific strength and high energy absorption, and overcomes the defect that the traditional two-dimensional negative Poisson's ratio honeycomb structure only presents the negative Poisson's ratio effect in a single dimension, so that the vibration absorbing unit 1 has higher isotropic consistency and is suitable for multi-axis loading. At the same time, the combination of the metal frame 11 and the elastic member 12 and the load block 13 inside it can achieve the effect of vibration reduction at a specified frequency point, and can avoid the phenomenon of prominence of low-frequency vibration line spectra. When the external excitation frequency is close to the natural frequency of the oscillator system, the energy of the elastic wave is greatly absorbed, thereby isolating the propagation of the elastic wave in the vibration absorption unit 1.

[0050] It is understandable that the meaning of "three-dimensional" in the three-dimensional negative Poisson's ratio effect is that the structure exhibits a negative Poisson's ratio effect in three axial directions. That is, when any axial direction is subjected to a tensile load or a compressive load, the other two directions simultaneously expand outward or contract inward. For example, when subjected to a vibration load, the vibration absorbing unit 1 with a three-dimensional negative Poisson's ratio effect will have better deformation efficiency and contraction performance due to the above deformation mechanism, and can absorb more energy from the external load.

[0051] Optionally, the metal frame 11 is made of alloy material to increase the overall load-bearing capacity and rigidity of the vibration absorbing unit 1. The elastic member 12 is made of a highly elastic polymer such as rubber, and the load block 13 is made of a high-density heavy object such as iron, copper or lead. The load block 13 and the elastic member 12 form a vibrator system through a fixing member 14.

[0052] Optionally, in some embodiments, Figure 4 As shown, the metal frame 11 includes: a top wall 111; a side wall 112, one end of which is connected to the top wall 111; a bottom wall 113, which is arranged opposite to the top wall 111, and the bottom wall 113 is connected to the other end of the side wall 112; wherein the side wall 112 is recessed toward the interior of the metal frame 11, and the side wall 112 is connected to the elastic member 12, and the elastic member 12 can be snapped into the metal frame 11.

[0053] In this embodiment, the metal frame 11 includes a top wall 111, a side wall 112 and a bottom wall 113. The top wall 111 and the bottom wall 113 are arranged opposite to each other, and the top wall 111 and the bottom wall 113 are located on both sides of the side wall 112. In the height direction, the top wall 111 is located above the side wall 112, and the bottom wall 113 is located below the side wall 112. At the same time, the side wall 112 is recessed toward the inside of the metal frame 11, forming a metal frame 11 with a three-dimensional negative Poisson's ratio effect. By expanding the two-dimensional concave hexagonal structure in an orthogonal plane and constructing it in a three-dimensional space in the form of a rod, that is, the top wall 111, the side wall 112 and the bottom wall 113 of the metal frame 11 can be understood as a kind of rod. There are four side walls 112, and the four side walls 112, the top wall 111, and the bottom wall 113 surround a hollow metal frame 11. The elastic member 12 is embedded in the metal frame 11. The shape of the connection between the elastic member 12 and the side wall 112 is the same as the concave shape of the side wall 112, so that the elastic member 12 is clamped inside the metal frame 11 to improve the connection stability between the elastic member 12 and the metal frame 11. At the same time, the elastic member 12 and the load block 13 embedded in the metal frame 11 are matched and fixed with the side wall 112 of the metal frame 11, providing a certain support effect when the vibration absorbing unit 1 is loaded and squeezed.

[0054] In addition, the connection between the elastic member 12 and the side wall 112 is fixed to each other by adhesive, so as to further improve the connection reliability between the elastic member 12 and the metal frame 11.

[0055] Optionally, in some embodiments, Figure 5 , Figure 6 and Figure 7As shown, the top wall 111 includes two cross-arranged top wall plates 1111, the bottom wall 113 includes two cross-arranged bottom wall plates 1131, the two ends of the side wall 112 are respectively connected to one end of the top wall plate 1111 and one end of the bottom wall plate 1131, and the size of the bottom wall plate 1131 is the same as that of the top wall plate 1111; the two ends of the side wall 112 are inclined toward the inside of the metal frame 11 along the height direction of the metal frame 11, and the height of the metal frame 11 is expressed as:

[0056]

[0057] Wherein, d represents the height of the metal frame 11 , H represents the length of the top wall plate 1111 and / or the bottom wall plate 1131 , and θ represents the concave angle of the side wall 112 .

[0058] In this embodiment, the top wall 111 and the bottom wall 113 have the same structure and size. The top wall 111 includes two cross-arranged top wall flat plates 1111, and the bottom wall 113 includes two cross-arranged bottom wall flat plates 1131. Both the top wall 111 and the bottom wall 113 are cross-shaped, and the setting direction of the top wall flat plate 1111 is the same as the setting direction of the bottom wall flat plate 1131. At the same time, the two ends of the side wall 112 are respectively connected to one end of the top wall plate 1111 and one end of the bottom wall plate 1131, and the two ends of the side wall 112 are gradually inclined toward the center direction of the side wall 112, and are inclined close to the inside of the metal frame 11 to form a concave side wall 112. The concave angle, the height of the metal frame 11, and the length of the top wall plate 1111 or the bottom wall plate 1131 satisfy the above relationship. That is, this embodiment limits the design parameters of the metal frame 11 so that the metal frame 11 has a three-dimensional negative Poisson's ratio effect, so that the vibration absorbing unit 1 has higher isotropic consistency and is suitable for multi-axis loading. It makes up for the defect that the two-dimensional negative Poisson's ratio honeycomb structure can only present a negative Poisson's ratio effect in a single dimension.

[0059] Optionally, in some embodiments, Figure 8 , Fig. 9 and Fig.10 As shown, the elastic member 12 includes two cross-arranged elastic strips 121. Along the length direction of the elastic strips 121, the end surfaces of the two elastic strips 121 are both concave inwards. The concave angle of the elastic strips 121 is the same as the inclination angle of the side wall 112. The length of the elastic member 12 is expressed as:

[0060]

[0061] Among them, Y represents the length of the elastic strip 121, H represents the length of the top wall plate 1111 and / or the bottom wall plate 1131, L represents the distance from one end of the side wall 112 to the angle turning point, θ represents the concave angle of the elastic strip 121, and N represents the width of the elastic strip 121.

[0062] In this embodiment, the elastic member 12 includes two cross-arranged elastic strips 121, and along the length direction of the elastic strips 121, the end faces of the two elastic strips 121 are both concave inwards, and the angle of the concave elastic strip 121 is the same as the inclination angle of the side wall 112. Among them, the length of the elastic strip 121, the length of the wall plate or the bottom wall plate 1131, the distance from one end of the side wall 112 to the angle turning point, the concave angle of the elastic strip 121, and the width of the elastic strip 121 satisfy the above relationship, that is, this embodiment enables the elastic member 12 to adapt to and match the internal space of the metal frame 11 by limiting the design parameters of the elastic member 12, thereby improving the connection stability between the elastic member 12 and the metal frame 11.

[0063] Optionally, in some embodiments, Fig.10 and Fig.11 As shown, the load block 13 is in the shape of a cylinder, and a second through hole 131 is provided at the center of the load block 13. The mass of the load block 13 is expressed as:

[0064] M=(1 / 2πR 2 -1 / 2πr 2 )kρ;

[0065] Wherein, M represents the mass of the load block 13 , π represents the pi, R represents the radius of the load block 13 , r represents the radius of the second through hole 131 , k represents the thickness of the load block 13 , and ρ represents the material density of the load block 13 .

[0066] In this embodiment, the load block 13 is in the shape of a cylinder, and a second through hole 131 is provided at the center of the load block 13. The number of load blocks 13 includes two, which are respectively provided on the upper and lower sides of the elastic member 12. The load block 13 is further fixed to the elastic member 12 by a fixing member 14, so that the load block 13 and the elastic member 12 form an oscillator system, thereby reducing the vibration caused by external interference and improving the service life of the mechanical equipment. At the same time, it can also absorb the energy of sound waves, thereby reducing the noise generated by the mechanical equipment. The mass of the load block 13, the radius of the load block 13, the radius of the second through hole 131, the thickness of the load block 13 and the material density of the load block 13 satisfy the above relationship, that is, this embodiment defines the design parameters of the load block 13, so that the oscillator system formed by the load block 13 and the elastic member 12 can eliminate low-frequency vibrations, greatly absorb the ability of elastic waves, and isolate the elastic waves outside the vibration absorption unit 1.

[0067] Optionally, in some embodiments, Fig.12As shown, a first through hole 122 is provided at the center of the elastic member 12, a second through hole 131 is provided at the center of the load block 13, and the fixing member 14 includes a stud bolt 141 and a fastening nut 142, the stud bolt 141 is provided in the first through hole 122 and the second through hole 131, and the fastening nut 142 can fix the load block 13 on the elastic member 12.

[0068] In this embodiment, a first through hole 122 is provided at the center of the elastic member 12, a second through hole 131 is provided at the center of the load block 13, the fixing member 14 includes a stud 141 and a fastening nut 142, the number of the load block 13 includes at least one, and the length of the stud 141 is greater than the thickness of the elastic member 12. When installing the load block 13, the stud 141 can be passed through the first through hole 122, and then the second through hole 131 of the load block 13 is inserted into the protruding stud 141, and the two ends of the stud 141 are tightened by the fastening nut 142 to complete the fixing of the load block 13. Of course, the number of the load block 13 can also include multiple, which can be set at one end of the elastic member 12 or at the upper and lower ends of the elastic member 12, and the load block 13 is further fixed to the elastic member 12 by the stud 141 and the fastening nut 142, so that the elastic member 12 and the load block 13 form a vibrator system to absorb vibration energy, improve the service life of the mechanical equipment, and absorb the noise generated by the mechanical equipment.

[0069] Optionally, in some embodiments, Fig.12 and Fig.13 As shown, the vibration absorbing unit 1 with three-dimensional negative Poisson's ratio effect also includes: an adhesion layer 15, located in the first through hole 122, connecting the elastic member 12 and the stud bolt 141; wherein the adhesion layer 15 can fix the stud bolt 141 in the first through hole 122.

[0070] In this embodiment, the vibration absorbing unit 1 also includes an adhesive layer 15, which is located in the first through hole 122. One side of the adhesive layer 15 is connected to the elastic member 12, and the other side of the adhesive layer 15 is connected to the stud bolt 141, so that the stud bolt 141 and the elastic member 12 are fixed to each other, thereby avoiding failure of the fixing member 14 due to irregular vibration energy, and further improving the installation stability of the load block 13.

[0071] According to a second aspect of the present invention, a vibration absorbing device 2 with a three-dimensional negative Poisson's ratio effect is provided, comprising the vibration absorbing unit 1 with a three-dimensional negative Poisson's ratio effect as proposed in the first aspect.

[0072] The vibration absorbing device 2 with three-dimensional negative Poisson's ratio effect provided by the present invention includes the vibration absorbing unit 1 with three-dimensional negative Poisson's ratio effect as proposed in the first aspect. Therefore, the vibration absorbing device 2 with three-dimensional negative Poisson's ratio effect has all the beneficial effects of the vibration absorbing unit 1 with three-dimensional negative Poisson's ratio effect proposed in the first aspect, which will not be repeated here.

[0073] Optionally, in some embodiments, Fig.14 As shown, the number of vibration absorbing units 1 includes multiple ones, and the multiple vibration absorbing units 1 are arranged in arrays along the x-axis, y-axis and z-axis directions, and every two vibration absorbing units 1 on the z-axis share a top wall 111 or a bottom wall 113 of a metal frame 11; wherein, the array number n1 on the z-axis is the number of honeycomb layers, the array number on the x-axis is n2, and the array number on the y-axis is n3, the number of vibration absorbing units 1 in a single layer of honeycomb is n2×n3, and the number of vibration absorbing units 1 in each layer of honeycomb is the same.

[0074] In this embodiment, the number of vibration absorbing units 1 includes multiple ones, and the vibration absorbing unit 1 is the smallest basic unit of the vibration absorbing device 2. Specifically, in a three-dimensional coordinate system, multiple vibration absorbing units 1 are arranged in an array along the x-axis, y-axis and z-axis directions, respectively, and every two vibration absorbing units 1 on the z-axis share a top wall 111 or a bottom wall 113 of a metal frame 11. That is, in a vibration absorbing device 2 composed of multiple vibration absorbing units 1, every two vibration absorbing units 1 on the z-axis share a top wall 111 or a bottom wall 113 of a metal frame 11. This arrangement allows gaps to exist between adjacent vibration absorbing units 1, has the advantage of being lightweight, provides more contact surfaces in a smaller space, and thus increases the ability to absorb vibration energy. In addition, the number of vibration absorbing units 1 in each layer of honeycomb is the same, so that the overall vibration absorption effect of the vibration absorbing device 2 is more balanced.

[0075] Optionally, in some embodiments, Fig.15 As shown, the number of the vibration absorbing units 1 includes multiple ones, and any vibration absorbing unit 1 shares a side wall 112 of the metal frame 11 with two adjacent vibration absorbing units 1 .

[0076] In this embodiment, the number of vibration absorbing units 1 includes multiple ones, and the vibration absorbing unit 1 is the smallest basic unit of the vibration absorbing device 2. In the three-dimensional coordinate system, any vibration absorbing unit 1 shares a side wall 112 of the metal frame 11 with two adjacent vibration absorbing units 1, so as to avoid the existence of gaps between the vibration absorbing units 1 and the vibration absorbing units 1. In the case of the same number of vibration absorbing units 1, this arrangement method can make the volume of the vibration absorbing device 2 smaller, the space utilization rate higher, and improve the vibration energy absorption capacity of the vibration device under unit volume.

[0077] In a specific application, the present invention provides a honeycomb dynamic vibration absorbing structure with a three-dimensional negative Poisson's ratio effect, such as Figure 1The figure shows a minimum vibration-absorbing structural unit (vibration-absorbing unit 1) provided in the present invention, which is composed of a three-dimensional negative Poisson's ratio honeycomb core (metal frame 11), an elastic member 12 embedded in the basic honeycomb cell, a load block 13, a fastening nut 142, and a double-headed threaded bolt 141.

[0078] like Figure 3 and Fig.12 As shown, the outer frame of the minimum vibration absorbing structural unit is a three-dimensional negative Poisson's ratio cell structure, and the elastic member 12 is embedded in the cell structure through slot matching, and an adhesive layer is provided between the two, and they are fixed to each other through a specific adhesive. The load block 13 is fixed to the elastic member 12 through a stud threaded bolt 141 and a fastening nut 142. The specific implementation method is as follows: the elastic member 12 has a cylindrical opening (first through hole 122) in the center, and the stud threaded bolt 141 passes through it; an adhesive layer 15 is provided between the opening of the elastic member 12 and the bolt, and the two are kept fixed to each other; the load block 13 is sleeved on the bolt through the central opening and is fastened to the elastic member 12 through a nut.

[0079] One of the core components of the honeycomb dynamic vibration absorption structure with three-dimensional negative Poisson's ratio effect proposed by the present invention is a three-dimensional negative Poisson's ratio honeycomb cell (metal frame 11). The special deformation mechanism of the cell enables it to exhibit a negative Poisson's ratio effect in multiple axes after being loaded. Specifically, by expanding the two-dimensional concave hexagonal structure in an orthogonal plane, a three-dimensional negative Poisson's ratio cell is constructed in a three-dimensional space in the form of a rod. Figure 4 Schematic diagram of the design of three-dimensional negative Poisson's ratio cell structure.

[0080] like Figure 5 , Figure 6 and Figure 7 As shown, the height of the three-dimensional negative Poisson's ratio honeycomb cell is d, and the cross-sections of all rods in the cell are set to be rectangles of the same size. The side lengths of the cross-section rectangles of the rods in the cell are t1 and t2 respectively. Since the cell rods will be shared with adjacent cells during the periodic array process, the sharing mode of the cells needs to be specifically analyzed under different arrays and connection methods. The cross-sections of the horizontal rods and the concave rods can be described as rectangles with side lengths of t1 and t2 respectively. The length of the rods in the horizontal direction (top wall 111 or bottom wall 113) is H, the length of the rods in the concave direction (side wall 112) is L, and the structural concave angle is θ. The relationship between the height of the three-dimensional negative Poisson's ratio honeycomb cell and the length of the rods in the concave direction can be expressed as:

[0081]

[0082] Theoretical analysis shows that the mechanical properties of the three-dimensional negative Poisson's ratio honeycomb of the dynamic vibration absorption structure can be determined by selecting appropriate design geometric parameters. At the micro level, the geometric shape of the cell, the thickness of the rod t1, t2, the length of the horizontal rod H, the length of the rod in the concave direction L and the structural concave angle θ are adjusted; at the macro level, the number of layers of the three-dimensional negative Poisson's ratio honeycomb and the number of cells contained between the layers are adjusted.

[0083] One of the core components of the honeycomb dynamic vibration absorption structure with three-dimensional negative Poisson's ratio effect proposed by the present invention is the vibrator system. Figure 8 , Fig. 9 , Fig.10 and Fig.12 As shown, the load block 13 is fixed to the elastic member 12 by bolts and nuts to form a vibrator system. According to the working principle of the dynamic vibration absorber: the stiffness of the elastic member 12 and the weight of the load block 13 directly affect the working frequency band of the dynamic vibration absorber. The stiffness of the elastic member 12 is related to the base material and the section modulus, and the weight of the load block 13 is also related to the base material and size of the base material.

[0084] like Figure 7 and Fig. 9 As shown, the elastic member 12 is a cross-shaped structure, and the intersecting rectangle is denoted as Y in length, N in width, and O in height, and the angle of the slot is equal to the concave angle θ of the cell. The elastic member 12 and the cell gap size are perfectly matched, and the following relationship exists between the two:

[0085]

[0086] like Figure 7 , Fig. 9 , Fig.10 and Fig.11 As shown, the mass of a single load block 13 is M, and the geometric dimensions of the load block 13 are: radius R, thickness k, matrix material density ρ, and the center aperture of the load block 13 (aperture of the second through hole 131) is r. The mass M of the load block 13 and the geometric dimensions have the following relationship:

[0087] M=(1 / 2πR 2 -1 / 2πr 2 )kρ;

[0088] The dynamic vibration absorption structure formed by the three-dimensional negative Poisson's ratio cell as the frame structure proposed in the present invention has the following vibration reduction principle: the rigid frame and the vibrator simulate the principle of the dynamic vibration absorber. When the external load propagates in the present invention, the elastic wave is localized by the minimum dynamic vibration absorption unit, and the local resonance mode is excited. The dynamic simplified model is as follows: Fig.16As shown. The simplified dynamic model includes a weight 16, a damper 17 and a spring 18. The damper 17 and the spring 18 support the weight 16 together. The external excitation load is defined as F, G represents the reaction force of the oscillator system, and x represents the displacement of the load block 13. When the main peak frequency of the excitation coincides with the natural frequency of the oscillator system, the natural mode of the oscillator system is excited. Due to the influence of the phase difference, the reaction force G of the oscillator system and the external load F can theoretically cancel each other out, making the elastic wave localized and unable to be transmitted outward, thereby achieving the purpose of attenuating low-frequency vibration energy.

[0089] The dynamic vibration absorbing structure with three-dimensional negative Poisson's ratio cells as the framework can form a three-dimensional honeycomb structure through different arrays and connection methods. The present invention proposes a combination method of multiple honeycomb dynamic vibration absorbing structures.

[0090] like Fig.14 As shown, the minimum three-dimensional negative Poisson's ratio vibration absorption structure is used as the basic unit. The minimum vibration absorption unit is arrayed along the x-axis, y-axis and z-axis respectively. Every two minimum vibration absorption units on the z-axis share a horizontal rod of a three-dimensional negative Poisson's ratio cell. They are parallel translated in the x-axis and y-axis directions, and adjacent units are in contact at the corners; the number of arrays on the z-axis is n1, which is the number of honeycomb layers; the number of arrays on the x-axis is n2, the number of arrays on the y-axis is n3, the number of single-layer honeycombs is n2*n3, and the number of minimum vibration absorption units in each honeycomb layer is the same.

[0091] like Fig.15 As shown, the minimum three-dimensional negative Poisson's ratio vibration-absorbing structure is taken as the basic unit, the inward concave angle of the external frame of the minimum vibration-absorbing unit is θ, and the outward folding angle is θ / 2. When arrayed, the inward concave angle of the reference unit can match the outward folding angles of the two minimum units, and the diagonal rods in each inward concave direction are shared with the adjacent cells, and so on, to fill the array in the space.

[0092] The present invention proposes a honeycomb dynamic vibration absorption structure with a three-dimensional negative Poisson's ratio effect, wherein the design of the three-dimensional negative Poisson's ratio honeycomb structure overcomes the defect that the traditional two-dimensional negative Poisson's ratio structure cannot simultaneously present the negative Poisson's ratio effect in multiple directions when subjected to multi-axial loads, increases the stiffness of the structure under dynamic loads such as vibration and impact, and improves the overall energy absorption capacity of the honeycomb structure.

[0093] The elastic member 12 and the load block 13 embedded in the three-dimensional negative Poisson's ratio honeycomb cell form an oscillator system, and the three-dimensional negative Poisson's ratio cell is used as a frame to form a dynamic vibration absorption structure. By reasonably setting the stiffness of the elastic member 12 and the type of the load block 13, the specific low-frequency line spectrum characteristics transmitted to the structure can be eliminated, effectively solving the bottleneck of the poor effect of traditional passive vibration reduction structures on low-frequency excitation.

[0094] In summary, the combination of the three-dimensional negative Poisson's ratio honeycomb cell and the dynamic vibration absorber effectively integrates their unique mechanical advantages, making it have the characteristics of lightweight, efficient energy absorption and elimination of low-frequency line spectrum in the design of vibration reduction and isolation structure. At the same time, the present invention has better parameter designability and better adaptability in different working environments.

[0095] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0096] The above is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features applied herein.

Claims

1. A vibration absorbing unit (1) having a three-dimensional negative Poisson's ratio effect, characterized in that: include: A metal frame (11), wherein the metal frame (11) has a three-dimensional negative Poisson's ratio effect; An elastic member (12) is disposed in the metal frame (11), and the elastic member (12) is connected to the inner wall of the metal frame (11); A load block (13) is disposed in the metal frame (11), and the load block (13) is connected to the elastic member (12); A fixing member (14) connects the elastic member (12) and the load block (13).

2. The vibration absorbing unit (1) with three-dimensional negative Poisson's ratio effect according to claim 1, characterized in that: The metal frame (11) comprises: Top wall (111); A side wall (112), one end of which is connected to the top wall (111); A bottom wall (113) is arranged opposite to the top wall (111), and the bottom wall (113) is connected to the other end of the side wall (112); The side wall (112) is recessed toward the interior of the metal frame (11), the side wall (112) is connected to the elastic member (12), and the elastic member (12) can be snap-fitted into the metal frame (11).

3. The vibration absorbing unit (1) with three-dimensional negative Poisson's ratio effect according to claim 2, characterized in that: The top wall (111) comprises two cross-arranged top wall plates (111), the bottom wall (113) comprises two cross-arranged bottom wall plates (1131), two ends of the side wall (112) are respectively connected to one end of the top wall plate (111) and one end of the bottom wall plate (1131), and the size of the bottom wall plate (1131) is the same as that of the top wall plate (111); Both ends of the side wall (112) are inclined toward the inside of the metal frame (11) along the height direction of the metal frame (11), and the height of the metal frame (11) is expressed as: Wherein, d represents the height of the metal frame (11), H represents the length of the top wall plate (111) and / or the bottom wall plate (1131), and θ represents the concave angle of the side wall (112).

4. The vibration absorbing unit (1) with three-dimensional negative Poisson's ratio effect according to claim 3, characterized in that: The elastic member (12) comprises two cross-arranged elastic strips (121), and along the length direction of the elastic strips (121), the end surfaces of the two elastic strips (121) are both concave inwards, and the concave angle of the elastic strips (121) is the same as the inclination angle of the side wall (112). The length of the elastic member (12) is expressed as: Wherein, Y represents the length of the elastic strip (121), H represents the length of the top wall plate (111) and / or the bottom wall plate (1131), L represents the distance from one end of the side wall (112) to the angle turning point, θ represents the concave angle of the elastic strip (121), and N represents the width of the elastic strip (121).

5. The vibration absorbing unit (1) with three-dimensional negative Poisson's ratio effect according to claim 1, characterized in that: The load block (13) is in the shape of a cylinder. A second through hole (131) is provided at the center of the load block (13). The mass of the load block (13) is expressed as: M=(1 / 2πR 2 -1 / 2πr 2 )kρ; Wherein, M represents the mass of the load block (13), π represents the pi, R represents the radius of the load block (13), r represents the radius of the second through hole (131), k represents the thickness of the load block (13), and ρ represents the material density of the load block (13).

6. The vibration absorbing unit (1) with three-dimensional negative Poisson's ratio effect according to any one of claims 1 to 5, characterized in that: A first through hole (122) is provided at the center of the elastic member (12), a second through hole (131) is provided at the center of the load block (13), the fixing member (14) comprises a stud bolt (141) and a fastening nut (142), the stud bolt (141) is provided in the first through hole (122) and the second through hole (131), and the fastening nut (142) is capable of fixing the load block (13) on the elastic member (12).

7. The vibration absorbing unit (1) with three-dimensional negative Poisson's ratio effect according to claim 6, characterized in that: Also includes: an adhesive layer (15), located in the first through hole (122), connecting the elastic member (12) and the stud bolt (141); The adhesive layer (15) is capable of fixing the stud bolt (141) in the first through hole (122).

8. A vibration absorbing device (2) having a three-dimensional negative Poisson's ratio effect, characterized in that: It comprises a vibration absorbing unit (1) having a three-dimensional negative Poisson's ratio effect as claimed in any one of claims 1 to 7.

9. The vibration absorbing device (2) with three-dimensional negative Poisson's ratio effect according to claim 8, characterized in that: The number of the vibration absorbing units (1) includes a plurality, the plurality of vibration absorbing units (1) are arranged in an array along the x-axis, y-axis and z-axis directions respectively, and every two vibration absorbing units (1) on the z-axis share a top wall (111) or a bottom wall (113) of the metal frame (11); The number of arrays n1 on the z-axis is the number of honeycomb layers, the number of arrays on the x-axis is n2, the number of arrays on the y-axis is n3, the number of vibration absorbing units (1) in a single honeycomb layer is n2×n3, and the number of vibration absorbing units (1) in each honeycomb layer is the same.

10. The vibration absorbing device (2) with three-dimensional negative Poisson's ratio effect according to claim 8, characterized in that: The number of the vibration absorbing units (1) includes a plurality, and any one of the vibration absorbing units (1) shares a side wall (112) of the metal frame (11) with two adjacent vibration absorbing units (1).

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