Integrated quasi-zero stiffness structure, quasi-zero stiffness vibration isolation device and vibration isolation method

Abstract

The present invention discloses an integrated quasi-zero stiffness structure, a quasi-zero stiffness vibration isolation device and a vibration isolation method. The integrated quasi-zero stiffness structure is composed of a plurality of parallel inclined beam units connected in series, rigid connectors connecting each beam segment, and constraint bearing components at both ends of the structure. The structure generates quasi-zero stiffness through the mutual constraint between adjacent beam segments, and its action mechanism is different from that of the existing quasi-zero stiffness structures. It does not require positive and negative stiffness matching, has accurate and stable quasi-zero stiffness, and has relatively high initial stiffness and high load-bearing capacity. The present invention discloses the form of this type of structure, the mechanical mechanism for the structure to generate quasi-zero stiffness, and the quasi-zero stiffness device based on this type of structure. Compared with the traditional quasi-zero stiffness vibration isolation device, it has the advantages of light weight, high strength, reliable stiffness, simple and integral structure, and broad application prospects.

Description

Technical Field

[0001] The present invention mainly relates to the field of structural vibration control, and particularly relates to an integrated quasi-zero stiffness structure, a quasi-zero stiffness vibration isolation device and a vibration isolation method. Background Art

[0002] As the main method of vibration control, the passive vibration isolation system has advantages such as low energy consumption, low cost, and strong reliability. The main control factor affecting the vibration isolation ability of the vibration isolation system is the stiffness of the system. Reducing the stiffness of the vibration isolation system can lower the natural frequency of the system to isolate vibration hazards. The quasi-zero stiffness vibration isolation system can make the whole system in a quasi-zero stiffness state by setting positive and negative stiffness structures and through optimized design and parameter adjustment, showing excellent vibration isolation performance of high static and low dynamic, and can effectively improve the stability and load-bearing capacity of the vibration isolation system. Therefore, the quasi-zero stiffness vibration isolation device has a wide range of applications in the fields of precision instrument vibration isolation, building and bridge earthquake resistance, ship machinery noise reduction, high-speed vehicle vibration reduction, etc.

[0003] Traditional quasi-zero stiffness vibration isolation devices mostly use springs as negative stiffness structures to offset the positive stiffness generated by the structure. However, the separated positive and negative stiffness structures make the overall structure relatively complex, occupy a large installation space, and at the same time, if the stiffness matching of one of the positive and negative stiffness structures is inaccurate, the whole device will lose the quasi-zero stiffness characteristic, greatly affecting the vibration isolation ability of the device. Therefore, how to make the vibration isolation device have a precisely controllable quasi-zero stiffness characteristic while ensuring the miniaturization of the device is one of the key issues in the current research field of structural vibration control.

[0004] Patents generating quasi-zero stiffness characteristics through positive and negative stiffness matching, such as "An Integrated Quasi-Zero Stiffness Vibration Isolation and Buffer Element and a Vibration Isolation and Buffer Assembly", use the buckling deformation of an inclined single solid beam as the negative stiffness mechanism, and match it with a buckling bar with positive stiffness characteristics to make the whole show quasi-zero stiffness characteristics within a certain range. It requires relatively precise positive and negative stiffness matching. Although the overall stiffness characteristic of the device can be changed by adjusting the bolt pre-tightening force, it needs to be continuously regulated during application and is difficult to generate a precisely determined quasi-zero stiffness. From the force-displacement curve provided by it, its initial stiffness and bearing capacity are relatively low, the length of the platform section is short and there is a certain fluctuation, the change range showing quasi-zero stiffness characteristics is small and not stable enough. In addition, the pre-tightening force and the inclination rate range of the beam rod generating quasi-zero stiffness characteristics are small, and the application range is limited. Summary of the Invention

[0005] The object of the present invention is to disclose an integrated quasi-zero stiffness structure, a quasi-zero stiffness vibration isolation device and a vibration isolation method. The integrated quasi-zero stiffness structure directly generates quasi-zero stiffness through the mutual restraint behavior between two beam segment units arranged in parallel, and the geometric dimension range capable of generating quasi-zero stiffness is wider, allowing a significantly increased initial stiffness and load-bearing capacity. The device based on this structure can be flexibly adjusted according to actual usage conditions.

[0006] In order to achieve the above technical object, the present invention adopts the following technical solutions:

[0007] An integrated quasi-zero stiffness structure, comprising: a vertical load-bearing structure, multiple groups of integrated quasi-zero stiffness beam bodies, and a constraint force transmission member;

[0008] Multiple groups of the integrated quasi-zero stiffness beam bodies are arranged symmetrically about the center of the vertical load-bearing structure;

[0009] Each group of integrated quasi-zero stiffness beam bodies includes two beam segment units arranged in parallel up and down. The two beam segment units are inclined or zigzag, and the inclination directions of the two beam segment units are the same. The middle parts of the two beam segment units are connected in series by a rigid connecting member capable of transmitting axial force, shear force and bending moment;

[0010] The displacement of one side of the integrated quasi-zero stiffness beam body is restricted by the fixed constraint force transmission member, and the other side is connected to the vertical load-bearing structure. The lateral displacement and bending of the integrated quasi-zero stiffness beam body are restricted by symmetry, and the horizontal deformations of the two beam segment units cancel each other out, and only vertical deformation can occur.

[0011] Furthermore, the lengths, widths and thicknesses of the two beam segment units arranged in parallel are the same. The length of the rigid connecting member l is the same as the width of the beam segment unit, the height of the rigid connecting member h is the spacing between the beam segment units, and the width of the rigid connecting member b is adjusted according to the thickness of the single-sided beam segment unit to ensure that the beam segment rotation angle at the rigid connecting member is close to zero.

[0012] The present invention further discloses a quasi-zero stiffness vibration isolation device, which is formed by connecting multiple of the above-mentioned integrated quasi-zero stiffness structures in parallel up and down. Among them, each integrated quasi-zero stiffness structure includes:

[0013] A vertical pressure-bearing part;

[0014] Four groups of integrated quasi-zero stiffness beam bodies, symmetrically arranged around the vertical pressure-bearing part with the vertical pressure-bearing part as the center. The other end of each integrated quasi-zero stiffness beam body is connected to a constraint force transmission member;

[0015] The vertical pressure-bearing part is provided with a first connection hole;

[0016] The first connection holes between every two vertical pressure-bearing parts are connected by force transmission through a first connection structure;

[0017] The vertical pressure-bearing part at the uppermost end is connected to the vibration isolation workpiece through a second connection structure and a pressure-bearing seat;

[0018] The constraint force transmission member is provided with second connection holes for connecting to the base.

[0019] The present invention further discloses a quasi-zero stiffness vibration isolation device, including two annular platforms arranged symmetrically up and down, and an annular vibration isolation unit connected between the two annular platforms through a constraint force transmission member. The annular vibration isolation unit is composed of a plurality of the integrated quasi-zero stiffness beam bodies and the constraint force transmission members connected in series circumferentially. Among them,

[0020] A plurality of first constraint force transmission members are symmetrically arranged with respect to the center of the first annular platform between the first annular platform at the uppermost end of the device and the annular vibration isolation unit. One end of the first constraint force transmission member is connected to the first annular platform, and the other end is connected to the second constraint force transmission member between every two of the integrated quasi-zero stiffness beam bodies on the annular vibration isolation unit;

[0021] A plurality of third constraint force transmission members are symmetrically arranged with respect to the center of the second annular platform between the second annular platform at the lowermost end of the device and the annular vibration isolation unit. One end of the third constraint force transmission member is connected to the second annular platform, and the other end is connected to the fourth constraint force transmission member between every two of the integrated quasi-zero stiffness beam bodies on the annular vibration isolation unit;

[0022] The first constraint force transmission member and the third constraint force transmission member are arranged in a circumferential dislocation along the annular platform.

[0023] Furthermore, when there are multiple annular vibration isolation units, a third annular platform is connected between two adjacent annular vibration isolation units.

[0024] The present invention further discloses a vibration isolation method based on the integrated quasi-zero stiffness structure. Under the action of a vertical load, due to the elastic jump phenomenon, the deformations of two mutually parallel beam segment units in the integrated quasi-zero stiffness beam body are different, resulting in a change in the axial stiffness of the integrated quasi-zero stiffness beam body, forming a constant vertical force, presenting a platform segment in the force-displacement curve. When the gravity load of the upper workpiece to be vibration-isolated corresponds to the vertical force of the platform segment of the structure, the structure exhibits stable quasi-zero stiffness characteristics.

[0025] Beneficial effects:

[0026] First. Compared with the existing quasi-zero stiffness vibration isolation devices, the vibration isolation device of the present invention does not need to set up mechanisms that can provide positive stiffness and negative stiffness respectively, nor does it require complex stiffness matching. The quasi-zero stiffness is generated by the mutual restraint and interaction of the axial constraint beams, which is different from the mechanism of generating quasi-zero stiffness in existing devices. The vibration isolation characteristics of high static and low dynamic are realized with a simple and lightweight structure, that is, it has both high load capacity and low natural frequency, can effectively reduce the vibration impact, and has good engineering application prospects. Moreover, it allows for higher initial stiffness and bearing capacity, and has better shock absorption and vibration control advantages.

[0027] Second. The integrated quasi-zero stiffness beam body of the present invention has relatively low stiffness requirements for the end constraint force transmission components. Traditional quasi-zero stiffness vibration isolation devices need to provide a large negative stiffness, so the stiffness requirements for their constraint components are relatively high. When using constraint components with relatively large stiffness, their mass and volume will also increase accordingly, and it is difficult for the constraint components to play a complete constraint role, resulting in the negative stiffness mechanism being difficult to reach a stable state. However, since the present invention does not combine the use of positive stiffness and negative stiffness mechanisms and does not need to provide too large a negative stiffness, it can directly achieve quasi-zero stiffness. Therefore, the stiffness requirements for the constraint force transmission components are relatively low, and at the same time, the structure is made simpler and lighter.

[0028] Third. The integrated quasi-zero stiffness beam body of the present invention is provided with rigid connecting pieces in the middle of multiple series-parallel beam segments, making the curvature change in the beam more uniform and the ultimate strain of the beam smaller. At the same time, when the device is damaged, it still has certain quasi-zero stiffness characteristics and high load-bearing capacity, improving the seismic performance of the structure to a certain extent and ensuring the structural safety.

[0029] Fourth. The present invention can form various vibration isolation devices by connecting the integrated quasi-zero stiffness structures in parallel up and down, such as Figure 8 , and connecting them in series in a left-right ring shape, such as Figure 11 . Through the series-parallel connection method, the length of the platform section of the load-displacement curve can be increased, providing a more stable quasi-zero stiffness for the structure. In actual engineering applications, by adjusting the curvature of the circumferential series vibration isolation device, successive and multi-directional quasi-zero stiffness can be provided, greatly improving the vibration isolation performance. At the same time, based on this integrated quasi-zero stiffness beam body, impact-resistant metamaterials can also be formed.

[0030] Fifth. The cylindrical vibration isolation device of the present invention, such as Figure 11 , reduces the stiffness requirements for the lateral constraint components by connecting the integrated quasi-zero stiffness beam bodies end to end, further reducing the structural mass.

[0031] Sixth. The integrated quasi-zero stiffness beam body described in the present invention can adjust the initial stiffness of the structure and the vertical force of the platform section through its overall height. The vibration isolation device described in the present invention arranges a certain number of integrated quasi-zero stiffness beam bodies so that the gravity load of the workpiece to be vibration isolated corresponds to the vertical force of the platform section of the structure, generating quasi-zero stiffness to isolate external vertical vibration excitation.

[0032] Seventh. The vibration isolation device described in the present invention has good deformation performance and good energy absorption effect.

[0033] Eighth. The integrated quasi-zero stiffness structure described in the present invention and the vibration isolation device based on this structure can both be realized by 3D printing or machining technology. The materials used can be materials such as nylon, rubber, and metal, and the materials and specifications can be selected and adjusted according to different loads. Description of the Drawings

[0034] Figure 1 is a schematic diagram of the integrated quasi-zero stiffness structure of the present invention;

[0035] Figure 2 is the front view of the integrated quasi-zero stiffness structure of the present invention;

[0036] Figure 3 is the left view of the integrated quasi-zero stiffness structure of the present invention;

[0037] Figure 4 is the top view of the integrated quasi-zero stiffness structure of the present invention;

[0038] Figure 5 is a schematic diagram of the mechanism of the series negative stiffness beams restricting each other to generate quasi-zero stiffness;

[0039] Figure 6 is the front view of the quasi-zero stiffness vibration isolation device in Embodiment 1 of the present invention;

[0040] Figure 7 is the top view of the quasi-zero stiffness vibration isolation device in Embodiment 1 of the present invention;

[0041] Figure 8 is the three-dimensional view of the quasi-zero stiffness vibration isolation device in Embodiment 1 of the present invention;

[0042] Figure 9 is the front view of the quasi-zero stiffness vibration isolation device in Embodiment 2 of the present invention;

[0043] Figure 10 is the top view of the quasi-zero stiffness vibration isolation device in Embodiment 2 of the present invention;

[0044] Figure 11 is the three-dimensional view of the quasi-zero stiffness vibration isolation device in Embodiment 2 of the present invention;

[0045] Figure 12 is the further deformation diagram of Embodiment 2;

[0046] Figure 13 is the force-displacement curve obtained from the test of Embodiment 1;

[0047] Figure 14 is the force-displacement curve obtained from the test of Embodiment 2;

[0048] Figure 15 is the force transmission and deformation process of the integrated quasi-zero stiffness beam body;

[0049] Figure 16 is the maximum vertical height L y on the minimum stiffness of the structure;

[0050] Figure 17 is the influence of the deformation in the beam on the lateral stiffness of the left beam;

[0051] Figure 18 is the force-displacement curve of the right beam under different lateral stiffness constraints;

[0052] In the figure: 10 - vertical bearing part; 11 - first connection hole; 20 - integrated quasi-zero stiffness structure; 21 - first beam segment unit; 22 - second beam segment unit; 23 - rigid connection member; 30 - constraint force transmission member; 31 - second connection hole; 32 - first constraint force transmission member; 33 - second constraint force transmission member; 34 - third constraint force transmission member; 35 - fourth constraint force transmission member; 4 - bearing seat; 5 - first connection structure; 6 - second connection structure; 70 - annular table surface; 71 - first annular table surface; 72 - second annular table surface; 73 - third annular table surface; 8 - third connection hole. Specific Embodiment

[0053] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings of the specification and specific embodiments.

[0054] Currently existing tests have shown that the overall height of the integrated quasi-zero stiffness structure will affect the platform of the structure force-displacement curve according to the magnitude of the vertical force and the initial stiffness, and the required structural bearing capacity can be obtained by changing the overall height of the integrated quasi-zero stiffness structure.

[0055] Combined with Figures 1 to 4 to illustrate the specific embodiment of the integrated quasi-zero stiffness structure. The present invention proposes an integrated quasi-zero stiffness structure, including a vertical bearing part, a constraint force transmission member, and an integrated quasi-zero stiffness beam body. A plurality of the integrated quasi-zero stiffness beam bodies are symmetrically connected around the vertical bearing part with the vertical bearing part as the center, and the other end of each integrated quasi-zero stiffness beam body is respectively connected to a constraint force transmission member;

[0056] The integrated quasi-zero stiffness beam body includes two beam segment units arranged in parallel up and down, and the middle parts of the two beam segment units arranged in parallel are connected by a rigid connecting member capable of transmitting axial force, shear force and bending moment;

[0057] Under the action of vertical force, the horizontal displacements of the two beam segment units arranged in parallel cancel each other out. The two beam segment units arranged obliquely or tortuously only undergo vertical deformation under the restriction of the constraint force transmission member. During vertical deformation, the two obliquely or tortuously arranged beam segment units generate negative stiffness characteristics through the stress energy storage-release process and elastic jump.

[0058] Further, on the inclined or tortuous beam segment, the two beam segments arranged in parallel are the same in size, shape and material.

[0059] Further, on the inclined or tortuous beam segment, the cross-sections of the two beam segments arranged in parallel are rectangular.

[0060] In the integrated quasi-zero stiffness beam body 20 of the two vertically load-bearing parts of the beam segments arranged in parallel in this example, the lengths, widths and thicknesses of the two beam segments arranged in parallel are the same. The width of the middle rigid connecting member is the same as the width of the beam segment, the thickness of the rigid connecting member is the distance between the beam segments, and the length of the rigid connecting member is about 4 times the thickness of the single-sided beam segment;

[0061] The vertical load-bearing part and the surface of the constraint force transmission member are respectively provided with first connection holes. The thickness of the vertical load-bearing part is about 2 times the distance between the parallel beam segments, and the thickness of the constraint force transmission member is the same as the distance between the parallel beam segments.

[0062] The constraint force transmission member is fixed at one end of the integrated quasi-zero stiffness beam body. Because of its high stiffness, it can play a role in restricting the horizontal displacement of the beam body; the vertical load-bearing part connects two symmetric integrated quasi-zero stiffness beam bodies and directly bears the vertical force. Under the action of the vertical force, due to the limited horizontal displacement of each beam segment in the integrated quasi-zero stiffness beam body, the horizontal displacements of the series-connected parallel beam segments cancel each other out. Therefore, the integrated quasi-zero stiffness beam bodies symmetric about the vertical load-bearing part only undergo vertical deformation under the restriction of the fixed constraint force transmission member.

[0063] By connecting the integrated quasi-zero stiffness beam bodies in parallel up and down or in series left and right, a vibration isolation device with excellent vibration isolation performance of high static and low dynamic can be formed, and for the two series-connected parallel beam segments with different curvatures, multi-directional and successive quasi-zero stiffness can be provided for the structure, improving the vibration isolation performance of the device and expanding the application range.

[0064] An integrated structure with zero stiffness characteristics can directly provide quasi-zero stiffness without setting up complex positive and negative stiffness mechanisms. Under the action of vertical loads, the beam segments gradually undergo elastic jumps, and strain energy is transferred between different parts. The beam segment on one side of the rigid connector first undergoes an elastic jump, the vertical deformation increases, the tangential stiffness decreases, and the strain energy storage is released. As the vertical deformation of the other constrained beam segment increases, the horizontal stiffness decreases. For the two beam bodies in series, the overall structure reaches a steady state when the vertical force is constant, showing extremely low tangential stiffness.

[0065] Furthermore, the present invention forms two vibration isolation devices by combining parallel and series integrated quasi-zero stiffness structures. On the premise of knowing the mass of the workpiece to be vibration isolated, a certain number of integrated quasi-zero stiffness structures can be arranged as needed for both of them, so that the gravity load of the workpiece to be vibration isolated corresponds to the vertical force of the platform section of the structure, generating quasi-zero stiffness to isolate external vertical vibration excitation. The following is illustrated by two specific embodiments.

[0066] Embodiment 1

[0067] Specific implementation manner of Device 1: In combination with Figures 6 to 8 Illustrate the specific implementation manner of the quasi-zero stiffness vibration isolation device formed by parallel connection based on the integrated structure. This device is composed of a vertical pressure-bearing part, a first connection structure, and an integrated quasi-zero stiffness structure combined in parallel up and down. The vertical pressure-bearing part is 48 mm long, 48 mm wide, and 10 mm high, with 9 first connection holes with a diameter of 6 mm arranged, and is connected to the first connection structure. A second connection structure that penetrates up and down is arranged inside the first connection structure, so that the device can be connected to the base, the upper pressure-bearing seat, and the workpiece to be vibration isolated through bolts.

[0068] On each layer of the integrated quasi-zero stiffness beam body, 4 groups are symmetrically arranged on the left and right, and are connected in parallel up and down through the first connection structure to form a whole. The two parallel beam segments are 50 mm long, 48 mm wide, and 1 mm thick, and the distance between the upper and lower parallel beam segments is 2 mm. The length and width of the rigid connector in the middle of the beam segments are the same as those of the beam body, and the thickness is 2 mm; the length and width of the middle vertical pressure-bearing part remain unchanged, and the thickness is set to 4 mm, and 9 first connection holes with a diameter of 6 mm are arranged on the surface;

[0069] The end constraint force transmission member of the integrated quasi-zero stiffness beam body is 48 mm long, 11.5 mm wide, and 72 mm high, and 2 second connection holes are symmetrically arranged, facilitating connection to the base through bolts.

[0070] The first connection structure connects the integrated quasi-zero stiffness structures connected in parallel up and down through the first connection holes to form a whole. The overall length of the device is 170 mm, the width is 170 mm, and the height is 110 mm. Through tests, it is measured that when the device is under the action of vertical loads and reaches the quasi-zero stiffness stable state, the vertical bearing capacity is about 170 N, and the initial stiffness is about 290 N / mm.

[0071] Example 2

[0072] Specific implementation manner of Device 2: Combined with Figures 9 to 11 the specific implementation manner of the cylindrical vibration isolation bearing formed by integrating the quasi-zero stiffness structures in series. This device is composed of an annular tabletop, a constraint force transmission member 3, and a circumferentially series-connected vibration isolation unit. The inner diameter of the vibration isolation device is 120 mm, and the outer diameter is 140 mm. The annular tabletop is symmetrically distributed in the upper, middle, and lower parts, with a width of 10 mm, a height of 5 mm, and a spacing of 45 mm between adjacent tabletops; in the integrated quasi-zero stiffness structure, the vertical load-bearing part has a radial length of 10 mm, a width of 5 mm, and a height of 20 mm, the upper part is arranged at the quarter-point position of the tabletop, and the lower part is connected to the integrated quasi-zero stiffness beam body. The horizontal projection length of the beam body is 45 mm, the width is 10 mm, and the thickness is 1 mm. The spacing between two parallel beam segments is 4 mm. The rigid connecting member has a radial length of 10 mm, a width of 3 mm, and a thickness of 2 mm. For the convenience of installation and fixation of the device, third connection holes are provided at the upper and lower parts of the device, and bolts are used to connect to the external workpiece to be vibration-isolated.

[0073] The integrated quasi-zero stiffness beam bodies are connected end to end, and are symmetrical in the upper, lower, left, and right directions, forming a cylinder, which reduces the requirements for the stiffness of the lateral constraint force transmission members. Through tests, it is measured that when the device is under vertical load and reaches the quasi-zero stiffness stable state, the vertical bearing capacity is about 40 N, and the initial stiffness is about 10 N / mm.

[0074] Different from the vertical parallel vibration isolation device in Embodiment 1, the circumferential series-connected vibration isolation device can provide self-constraint in the horizontal direction, reduces the requirements for the lateral stiffness of the structure, further reduces the structural mass, and its platform section length of the force-displacement curve can be adjusted by adjusting the circumferential curvature.

[0075] In addition, due to the good deformation performance of the annular series-connected vibration isolation device, when it is subjected to mechanical impact, it can convert mechanical energy into internal energy and potential energy through its own deformation, and has a good energy absorption effect.

[0076] The quasi-zero stiffness vibration isolation device based on the integrated quasi-zero stiffness structure can be realized by 3D printing or machining technology. The materials used can be nylon, rubber, metal and other materials, and the materials, specifications and quantities can be selected according to different loads.

[0077] Example 3

[0078] The integrated quasi-zero stiffness structure and the quasi-zero stiffness vibration isolation device can be made of metal. When the thickness of the beam body is small, a vertical load is gradually applied, and the beam body will gradually buckle. One end of the beam body reaches the subcritical state. By using the axial mutual restraint effect between the beam bodies, the force-displacement curve shows a platform section, and the structure exhibits quasi-zero stiffness characteristics. The beam body used in the test has a thickness of 2 mm, a horizontal projection length of 30 mm, and a maximum height of the structure of 8 mm. The vertical bearing capacity of the structure when it reaches the quasi-zero stiffness stable state is measured to be about 100 N, and it has good service performance.

[0079] It can be seen from the test results that when the integrated quasi-zero stiffness structure is composed of several parallel beam segments connected in series, the low-stiffness platform area is easily observable. Their tangential stiffness is almost always very close to zero, regardless of the geometric shape of the structure, and is determined by Figure 16 , the tangential stiffness of the structure is insensitive to L y , but the platform strength increases with the increase of L y , which is beneficial to the production and use of the integrated quasi-zero stiffness structure and the quasi-zero stiffness device based on this structure. Its service performance is insensitive to the dimensional errors generated during the processing; it has the characteristics of low cost and high reliability, improves the scope of application, can significantly reduce the structural seismic frequency under seismic catastrophes, increase the structural damping ratio, and enhance the seismic performance of the structure.

Claims

1. An integrated quasi-zero stiffness structure, characterized in that, Comprising: A vertical load-bearing structure, multiple groups of integrated quasi-zero stiffness beam bodies, and constraint force transmission members; Multiple groups of the integrated quasi-zero stiffness beam bodies are arranged symmetrically about the center of the vertical load-bearing structure; Each group of integrated quasi-zero stiffness beam bodies includes two beam segment units arranged in parallel up and down. The two beam segment units are arranged obliquely or tortuously, and the inclination directions of the two beam segment units are the same. The middle parts of the two beam segment units are connected in series by a rigid connecting member capable of transmitting axial force, shear force, and bending moment; The displacement of one side of the integrated quasi-zero stiffness beam body is restricted by the fixed constraint force transmission member, and the other side is connected to the vertical load-bearing structure. The lateral displacement and bending of the integrated quasi-zero stiffness beam body are restricted by symmetry, and the horizontal deformations of the two beam segment units cancel each other out, and only vertical deformation can occur; The lengths, widths, and thicknesses of the two beam segment units arranged in parallel are the same. The length l of the rigid connecting member is the same as the width of the beam segment unit, the height h of the rigid connecting member is the spacing between the beam segment units, and the width b of the rigid connecting member is adjusted according to the thickness of the single-sided beam segment unit to ensure that the beam segment rotation angle at the rigid connecting member is close to zero.

2. The integrated quasi-zero stiffness structure according to claim 1, wherein The integrated quasi-zero stiffness structure is realized by 3D printing or machining, and the materials used are nylon, rubber, or metal materials.

3. A quasi-zero stiffness vibration isolation device, characterized in that, It is formed by connecting multiple integrated quasi-zero stiffness structures as described in claim 1 in parallel up and down. Among them, each integrated quasi-zero stiffness structure includes: a vertical pressure-bearing part; Four groups of integrated quasi-zero stiffness beam bodies are symmetrically arranged around the vertical pressure-bearing part with the vertical pressure-bearing part as the center. The other end of each integrated quasi-zero stiffness beam body is connected to a constraint force transmission member; The vertical pressure-bearing part is provided with a first connection hole; Force is transmitted and connected between the first connection holes between every two vertical pressure-bearing parts through a first connection structure; The vertical pressure-bearing part at the uppermost end is connected to the vibration isolation workpiece through a second connection structure and a pressure-bearing seat; The constraint force transmission member is provided with a second connection hole for connecting to the base.

4. A quasi-zero stiffness vibration isolation device, characterized in that, It includes two annular table surfaces arranged symmetrically up and down, and an annular vibration isolation unit connected between the two annular table surfaces through a constraint force transmission member. The annular vibration isolation unit is composed of multiple integrated quasi-zero stiffness beam bodies and constraint force transmission members as described in claim 1 connected in series circumferentially. Among them, multiple first constraint force transmission members are symmetrically arranged with the center of the first annular table surface between the first annular table surface at the uppermost end of the device and the annular vibration isolation unit. One end of the first constraint force transmission member is connected to the first annular table surface, and the other end is connected to a second constraint force transmission member between every two of the integrated quasi-zero stiffness beam bodies on the annular vibration isolation unit; Multiple third constraint force transmission members are symmetrically arranged with the center of the second annular table surface between the second annular table surface at the lowermost end of the device and the annular vibration isolation unit. One end of the third constraint force transmission member is connected to the second annular table surface, and the other end is connected to a fourth constraint force transmission member between every two of the integrated quasi-zero stiffness beam bodies on the annular vibration isolation unit; The first constraint force transmission member and the third constraint force transmission member are arranged in a circumferentially staggered manner along the annular table surface.

5. The quasi-zero stiffness vibration isolation device according to claim 4, wherein, When there are multiple annular vibration isolation units, a third annular table surface is connected between two adjacent annular vibration isolation units.

6. The quasi-zero stiffness vibration isolation device according to any one of claims 3 to 5, characterized in that The quasi-zero stiffness vibration isolation device is realized by 3D printing or machining, and the materials used are nylon, rubber or metal materials.

7. A vibration isolation method based on the integrated quasi-zero stiffness structure described in claim 1, characterized in that, Under the action of vertical load, due to the elastic jump phenomenon, the deformations of two parallel beam segments in the integrated quasi-zero stiffness beam body are different, resulting in a change in the axial stiffness of the integrated quasi-zero stiffness beam body, forming a constant vertical force, which presents a platform segment in the force-displacement curve. When the gravity load of the upper workpiece to be vibration isolated corresponds to the vertical force of the platform segment of the structure, the structure exhibits stable quasi-zero stiffness characteristics.

Images