Self-contact superposition complementary type multistable quasi-zero stiffness vibration isolation device and method

Abstract

The invention discloses a self-contact superposition complementary type multi-stable quasi-zero stiffness vibration isolation device and method. The device is a self-contact superposition complementary type multi-stage multi-stable vibration isolation device design strategy provided by analogy of a special multi-layer structure of plant petals. A plurality of quasi-zero stiffness (QZS) platform areas with obvious gradient difference in bearing capacity can be obtained by utilizing the superposition complementary effect and contact enhancement behavior of interlayer buckling stiffness of a multi-layer structure, and each QZS platform can achieve an excellent low-frequency broadband vibration isolation effect. Meanwhile, by means of coupling interaction after interlayer contact, the energy loss capacity is effectively improved, and the bearing capacity is improved. Compared with an existing QZS vibration isolation device, the QZS vibration isolation device has the advantages that the bearing capacity is obviously improved, a working QZS platform is effectively widened, and the vibration reduction application requirements for the low-frequency vibration reduction effect and the reliable bearing strength in actual engineering can be well met.

Description

Technical Field

[0001] The invention belongs to the technical field of passive vibration isolation, and in particular relates to a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device and method. Background Art

[0002] Although the traditional linear vibration isolation system can achieve vibration isolation in the medium and high frequency bands, its attenuation effect on low-frequency vibration is very limited. According to the classical vibration isolation theory, if the system is to achieve the vibration isolation effect in the low frequency band, the natural frequency of the system must be reduced. For the traditional linear vibration isolation system, this will lead to a decrease in the system stiffness, the corresponding load-bearing capacity will also decrease, the static deformation of the vibration isolation system will increase, and the working space will increase; at the same time, the lower the stiffness of the vibration isolation system, the worse the stability of the vibration isolation system.

[0003] The vibration isolation structure with quasi-zero stiffness characteristics can well make up for the shortcomings of traditional linear vibration isolation technology. By reducing the dynamic stiffness of the vibration isolation system, improving the static stiffness of the system, and reducing the natural frequency of the vibration isolation system, it exhibits a unique "high static and low dynamic" stiffness characteristic, which can reduce the transmission rate of force or displacement, so that the vibration isolation system can achieve excellent low-frequency vibration isolation effect under the premise of having a certain load-bearing capacity.

[0004] Most of the QZS structures proposed in the past are obtained by combining positive stiffness components (PS) and negative stiffness components (NS), which will lead to problems such as the vibration isolation device being too bulky, occupying a large installation space, being difficult to manufacture and assemble, and having poor stability. Compared with the design method of combining positive and negative stiffness components, the compliant mechanism design method can realize the integrated, lightweight, compact and modular design of the QZS structure. However, the load-bearing performance of the existing compliant QZS structure is poor, and the obtained QZS platform area is narrow, which makes it impossible to stably and reliably realize the integrated design of load-bearing and vibration isolation. Therefore, it is necessary to develop a new QZS structural design form to realize an effective integrated design of load-bearing and vibration isolation that can be used in actual engineering. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing quasi-zero stiffness vibration isolation technology and provide a self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device and method for achieving excellent low-frequency wide-band vibration isolation effect on the basis of considerable bearing capacity, while being able to obtain a wider QZS vibration isolation platform area.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: A self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device comprises an outer layer structure, a middle layer structure, an inner layer structure and a heightening structure. The outer layer structure, the middle layer structure and the inner layer structure are independent of each other and are connected and combined through the heightening structure to form an integrated vibration isolation device.

[0007] A further improvement of the present invention is that the total height of the device is 103 mm, and the curved beam contours of the outer structure, the middle structure and the inner structure all satisfy the equation ,in x The value ranges are -52.4mm to 52.4mm, -29.0mm to 29.0mm and -14.5mm to 14.5mm respectively. The oblique straight beams of the outer structure, middle structure and inner structure are x The positive axis angles are 100° and 80° respectively.

[0008] A further improvement of the present invention is that the height of the portion of the height-increasing structure in contact with the outer layer structure is 32 mm, and the height of the portion of the height-increasing structure in contact with the middle layer structure is 11 mm.

[0009] A further improvement of the present invention is that, by utilizing the complementary effect of the interlayer buckling stiffness superposition and the contact enhancement behavior of the outer layer structure, the middle layer structure and the inner layer structure after contact, multiple QZS platform areas with obvious gradient differences in bearing capacity are obtained, and multiple QZS platforms can achieve excellent low-frequency wide-band vibration isolation effects.

[0010] A further improvement of the present invention is that by adjusting the geometric parameters of the vibration isolation device, including the in-plane thickness of the outer layer structure, the angle of the oblique straight beam of the middle layer structure, etc., the various QZS platform characteristics of the vibration isolation device, including the position of the QZS platform and the vibration isolation effect of the QZS platform, can be directly adjusted.

[0011] A further improvement of the present invention is that, through theoretical model analysis, the elastic restoring force of the single-layer structure of the vibration isolation device F With displacement x There is a cubic function relationship without constant terms, that is, by reasonably adjusting the geometric parameter values ​​of the single-layer structure, the QZS characteristics can be achieved in the preset compression displacement range.

[0012] A further improvement of the present invention is that by symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage QZS type vibration absorption-vibration isolation integrated device is constructed, which consists of two external frames and a QZS type local resonance unit.

[0013] A further improvement of the present invention is that a gap is left between the two outer frames in the initial state, and the internal QZS type local resonance unit can achieve the expected compression state at a certain QZS platform position, thereby obtaining excellent low-frequency vibration reduction capability.

[0014] A further improvement of the present invention is that the load-bearing and vibration reduction functions of the device are designed independently, the two external frames are responsible for the load-bearing after the contact is closed, and the internal QZS type local resonance unit is responsible for vibration absorption after reaching the pre-compression state. With the synergistic effect of the two-part structure, an integrated load-bearing and vibration reduction design can be achieved under large load conditions.

[0015] A self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device method, characterized in that the method is based on the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device, comprising: It can exhibit different steady-state configurations under different external loads. When the external load is small, the vibration isolation device is in the first QZS platform state with general bearing capacity. The first QZS platform can be used to effectively block the low-frequency and wide-band vibration energy. As the external load increases, the vibration isolation device successively reaches the second QZS platform state and the third QZS platform state with better bearing capacity. The second QZS platform and the third QZS platform can be used respectively to achieve excellent low-frequency and wide-band vibration isolation performance under high bearing capacity, and finally achieve low-frequency and wide-band vibration isolation effects under various low, medium and high bearing pressure states.

[0016] Compared with the prior art, the present invention has at least the following beneficial technical effects: 1. Through the complementary effect of buckling stiffness superposition and contact enhancement behavior between multi-layer discrete structures, a variety of steady-state configurations can be obtained under different contact conditions, thereby realizing multiple QZS platform areas with obvious gradient differences in bearing capacity, which is equivalent to the superposition of QZS platform intervals of various steady-state configurations; 2. Through structural optimization design and utilizing the contact enhancement behavior of multi-layer discrete structures after interlayer contact, a QZS platform with a large load-bearing capacity is realized; 3. With the help of the coupling interaction between the multi-layer discrete structures after the inter-layer contact, the equivalent damping loss factor of the vibration isolation device as a whole is significantly improved, and the energy loss capacity of the vibration isolation device is effectively enhanced; 4. The mechanical properties of each layer of discrete structure can be designed completely independently, and the mechanical properties of each layer of discrete structure after contact satisfy the linear superposition relationship; 5. By symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage QZS vibration absorption-vibration isolation integrated device was constructed. Based on the design concept of "absorption instead of isolation", the external frame and the internal QZS type local resonance unit are used to realize the load-bearing and vibration absorption functions respectively, which can realize the load-bearing-vibration reduction integrated design under large load conditions.

[0017] In summary, according to the above characteristics of a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device provided by the present invention, the vibration isolation device provided by the present invention can achieve excellent vibration isolation effect in a wide bandwidth range of the low frequency band on the basis of obtaining considerable bearing capacity. This device is a design strategy of a self-contact superposition complementary multi-stage multi-stable vibration isolation device proposed by analogy with the special multi-layer structure of plant petals. It utilizes the superposition complementary effect and contact enhancement behavior of the interlayer buckling stiffness of the multi-layer structure to obtain multiple quasi-zero stiffness platform areas with obvious gradient differences in bearing capacity. At the same time, with the help of the coupling interaction after the interlayer contact, the energy loss capacity is effectively improved, and the bearing capacity is improved. In addition, for ultra-large load application conditions, a design scheme based on "absorption instead of isolation" is proposed. By symmetrically arranging two self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage stiffness vibration absorption-vibration isolation integrated device is constructed. In summary, compared with the existing QZS vibration isolation device, the bearing capacity of this QZS vibration isolation device is significantly improved, and the QZS vibration isolation platform is effectively widened, which can well meet the vibration reduction application requirements for low-frequency vibration reduction effect and reliable bearing strength in actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The design idea of ​​the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device is presented; Figure 2 Five types of adjustable parameter distributions of self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 3 The simulation results of the quasi-static force-displacement compression curve of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 4a Setting the constraint conditions for dynamic analysis of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 4b The simulation results of the vibration isolation effect of the first QZS platform of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 4c The simulation results of the vibration isolation effect of the second QZS platform of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 4d The vibration isolation effect simulation results of the third QZS platform of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 5a The experimental test results of the quasi-static force-displacement compression curve of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device; Figure 5b The vibration isolation effect test results of the first QZS platform and the second QZS platform of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device are shown in Figure 1. Figure 6 It is a model of a multi-stage stiffness vibration absorption-vibration isolation integrated device with "absorption instead of isolation" and its principle diagram; Figure 7a It is the simulation result of the vibration reduction effect of the multi-stage stiffness vibration absorption and vibration isolation integrated device in the first QZS platform compression state, the second QZS platform compression state and the third QZS platform compression state; Figure 7b These are the experimental test results of the vibration reduction effect of the multi-stage stiffness vibration absorption and vibration isolation integrated device in the compression state of the first QZS platform and the compression state of the second QZS platform. DETAILED DESCRIPTION

[0019] The technical scheme in the implementation case of the present invention is described below in conjunction with the relevant calculation and measurement results of the implementation case of the present invention in the accompanying drawings. Obviously, the implementation case described is only a part of the implementation case of the present invention, not all the implementation cases. Based on the implementation case in the present invention, all other implementation cases obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

[0020] Example 1 The present invention provides a self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device, comprising an outer layer structure 1, a middle layer structure 2, an inner layer structure 3 and a heightening structure 4. The outer layer structure 1, the middle layer structure 2 and the inner layer structure 3 are independent of each other and are connected and combined by the heightening structure 4 to form an integrated vibration isolation device.

[0021] In this embodiment, the total height of the device is 103 mm, and the curved beam contours of the outer structure 1, the middle structure 2, and the inner structure 3 all satisfy the equation ,in x The value ranges are -52.4mm to 52.4mm, -29.0mm to 29.0mm and -14.5mm to 14.5mm respectively. The oblique straight beams of the outer structure 1, the middle structure 2 and the inner structure 3 are x The positive axis angles are 100° and 80° respectively. The height of the contact part between the heightened structure 4 and the outer structure 1 is 32 mm, and the height of the contact part between the heightened structure 4 and the middle structure 2 is 11 mm.

[0022] In this embodiment, by utilizing the complementary effect of interlayer buckling stiffness superposition and contact enhancement behavior of the outer layer structure 1, the middle layer structure 2 and the inner layer structure 3 after contact, multiple QZS platform areas with obvious gradient differences in bearing capacity are obtained, and multiple QZS platforms can achieve excellent low-frequency wide-band vibration isolation effect.

[0023] In this embodiment, by means of the coupling interaction between the outer layer structure 1, the middle layer structure 2 and the inner layer structure 3 after contact and merging, not only the bearing capacity of the device is significantly improved, but also the strain energy density of the overall structure of the device is significantly improved, and the damping loss capacity of the device for vibration energy is effectively enhanced.

[0024] In this embodiment, by adjusting the geometric parameters of the vibration isolation device, including the in-plane thickness of the outer layer structure 1, the oblique straight beam angle of the middle layer structure 2, etc., the various QZS platform characteristics of the vibration isolation device can be directly adjusted, including the position of the QZS platform and the vibration isolation effect of the QZS platform.

[0025] In this embodiment, through theoretical model analysis, the elastic restoring force of the single-layer structure of the vibration isolation device is F With displacement x There is a cubic function relationship without constant terms, that is, by reasonably adjusting the geometric parameter values ​​of the single-layer structure, the QZS characteristics can be achieved in the preset compression displacement range.

[0026] In this embodiment, the outer layer structure 1, the middle layer structure 2, and the inner layer structure 3 are completely independently adjustable, the design parameters of each layer structure can be independently determined according to needs, and the coupling mechanical properties of each layer structure after contacting each other satisfy a linear superposition relationship.

[0027] In this embodiment, a multi-stage QZS type vibration absorption and isolation integrated device is constructed by symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, which consists of two external frames 5 and a QZS type local resonance unit 6.

[0028] In this embodiment, a gap is left between the two external frames 5 in the initial state, and the size of the gap can be customized so that when the two are in contact and closed, the internal QZS type local resonance unit 6 can achieve the expected compression state at a certain QZS platform position, thereby obtaining excellent low-frequency vibration damping capability.

[0029] In this embodiment, the load-bearing and vibration reduction functions of the device are designed independently. The two external frames 5 are responsible for load-bearing after the contact is closed, and the internal QZS type local resonance unit 6 is responsible for vibration absorption after reaching the pre-compression state. The synergistic effect of the two-part structure can effectively realize the load-bearing and vibration reduction integrated design under large load conditions.

[0030] Example 2 The present invention provides a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device method, comprising: It can exhibit different steady-state configurations under different external loads. When the external load is small, the vibration isolation device is in the first QZS platform state with general bearing capacity. The first QZS platform can be used to effectively block the low-frequency and wide-band vibration energy. As the external load increases, the vibration isolation device successively reaches the second QZS platform state and the third QZS platform state with better bearing capacity. The second QZS platform and the third QZS platform can be used respectively to achieve excellent low-frequency and wide-band vibration isolation performance under high bearing capacity, and finally achieve low-frequency and wide-band vibration isolation effects under various low, medium and high bearing pressure states.

[0031] Example 3 The present invention provides a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device, which is composed of an outer layer structure 1, a middle layer structure 2, an inner layer structure 3 and a heightening structure 4. By symmetrically arranging two self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage QZS type vibration absorption-vibration isolation integrated device is constructed, including two external frames 5 and a QZS type local resonance unit 6.

[0032] 1. Design and experimental verification of a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device Inspired by the multi-layer petal structure in nature, a new self-contact superposition complementary multi-stable QZS vibration isolation device is proposed by equivalently and optimizing the original petal structure. Figure 1 As shown. The final optimized vibration isolation device consists of two parts: a deformable part made of TPU material and an auxiliary part made of aluminum alloy. Among them, the deformable part includes three discrete structures of outer layer, middle layer and inner layer. The deformable part obtains the expected multiple QZS platforms with different load-bearing capacities through deformation contact. The auxiliary part mainly provides a larger deformation working space between the discrete structures of each layer. The main design parameters of the vibration isolation device include the outer layer thickness B 1 , middle layer thickness B 2 、Inner layer thickness B 3 , the distance between the outer layer and the middle layer H 1 And the distance H between the middle layer and the inner layer 2 , as attached Figure 2 As an implementation case, a multi-layer QZS vibration isolation device is designed with an outer layer thickness of B 1 , middle layer thickness B 2 And the inner layer thickness B 3 Both are 20mm, the distance between the outer layer and the middle layer is H 1 The distance between the middle layer and the inner layer is 30 mm. 2 The quasi-static force-displacement compression curve is shown in the attached figure. Figure 3As shown, it can be seen that this type of vibration isolation device can obtain three QZS platforms with obvious gradient differences in load-bearing capacity under three steady-state configurations, namely the first steady-state QZS platform with a load-bearing capacity of 21.1 N, the second steady-state QZS platform with a load-bearing capacity of 107.1 N, and the third steady-state QZS platform with a load-bearing capacity of 137.7 N. The feasibility of realizing the design of a high-load-bearing and wide QZS platform with this type of vibration isolation device structure has been verified.

[0033] The above attached Figure 3 The QZS characteristics of this type of vibration isolation device are only studied from the perspective of statics. Therefore, the dynamic characteristics of the vibration isolation device are analyzed to illustrate its excellent low-frequency and broadband vibration isolation effect. The simulation constraint conditions for the multi-layer vibration isolation device are set as shown in the attached figure. Figure 4a As shown in the figure, a negative Z-axis compression displacement is applied from the top surface of the vibration isolation device to compress it to a certain expected steady-state configuration. A completely fixed constraint is set on the bottom surface of the device and a positive Z-axis sweep acceleration excitation is applied. At the same time, acceleration input points A are set on the bottom and top surfaces of the device. in and acceleration output point A out , by calculating the vibration acceleration transmission loss T = 20lg (A out / A in ) is used to measure the vibration isolation effect of the vibration isolation device.

[0034] The vibration isolation effects under the three steady-state configurations are calculated as shown in the attached figure. Figure 4b , Attachment Figure 4c and attached Figure 4d Attached Figure 4b The first QZS platform shows the vibration isolation capability of the first steady-state configuration. It can be seen that the first QZS platform starts to show vibration isolation effect from about 8.6Hz, and the best vibration isolation effect of 18.7dB appears around 70.1Hz. Except for a small range around 340Hz, the first QZS platform can achieve obvious vibration isolation effect for almost all frequency bands below 500Hz. Figure 4c The vibration isolation effect of the second stable configuration QZS platform and the attached Figure 4dThe analysis of the vibration isolation effect of the third steady-state configuration QZS platform is the same as above. The second QZS platform began to show vibration isolation effect from about 18.2Hz, and the best vibration isolation effect of 26.9dB appeared near 112.9Hz. Except for a small range near 320Hz, the second QZS platform can also achieve good vibration isolation effect for almost all frequency bands below 500Hz. The third QZS platform can show vibration isolation effect from the lowest input frequency of 5Hz, and the acceleration transmission loss in the whole frequency band of 5-500Hz is negative, that is, it can completely achieve excellent vibration isolation effect for the vibration energy in the whole frequency band of 5-500Hz, among which the best vibration isolation effect of 31.1dB is shown near 317.0Hz.

[0035] As attached Figure 5a As shown in the figure, the performance of the processed vibration isolation device samples was verified using a quasi-static compression test bench. It can be seen that the test results are consistent with the simulation results in the previous article. The experimental test results also show that this type of vibration isolation device can produce three QZS platforms with obvious gradient differences in bearing capacity, and the experimental test curves are basically consistent with the simulation curves. Figure 5b As shown in the figure, the vibration isolation effect of multiple QZS platforms of the vibration isolation device sample was tested and verified by using a vibration measurement test bench. Due to limited experimental conditions, only the vibration isolation effect of the first and second QZS platforms was tested, and the test results were basically consistent with the simulation calculation results. In summary, combined with the static analysis results and dynamic analysis results of the vibration isolation device, it is shown that this type of device can produce multiple QZS platforms with obvious gradient differences in load-bearing capacity, and each QZS platform can show excellent vibration isolation effect for low-frequency broadband vibration energy below 500Hz, verifying the feasibility of realizing the integrated design of load-bearing and vibration isolation through this type of multi-layer self-contact superimposed complementary structure.

[0036] 2. Design and experimental verification of a multi-stage stiffness vibration absorption and isolation integrated device that uses absorption instead of isolation Due to the limitations of the working principle of vibration isolation technology itself, it is quite challenging to achieve ultra-large load-bearing and vibration isolation integrated design by relying solely on vibration isolation. Therefore, based on the design concept of "absorption instead of isolation", by installing the load-bearing function and vibration reduction function in different components, the ultra-large load-bearing and vibration isolation integrated design can be achieved efficiently and conveniently. Figure 6As shown, the multi-stage stiffness vibration absorption and isolation integrated device is composed of an external bearing frame and a QZS type local resonance unit. Among them, the QZS type local resonance unit is composed of two mirror-symmetrically arranged self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation devices. By properly adjusting the reserved distance between the external bearing frames, when the two frames are in contact and closed, the internal QZS type local resonance unit can be in a certain stable configuration compression state of the expected design, and the two self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation devices are both in a certain QZS platform position, that is, the equivalent stiffness of the "spring-oscillator" system of the local resonance unit is approximately zero, which can achieve effective dissipation of low-frequency vibration energy.

[0037] As attached Figure 7a As shown in the figure, by adjusting the reserved space between the external frames, the vibration acceleration transmission loss of the QZS type local resonance unit in the compression state of the first QZS platform, the second QZS platform and the third QZS platform is calculated respectively. The calculation results show that under the compression state of the three QZS platforms, the "absorption instead of isolation" multi-stage stiffness vibration absorption-vibration isolation integrated device can achieve a good vibration isolation effect on the low-frequency broadband vibration energy in the frequency band of 5-355Hz. Among them, the first QZS platform compression can achieve an average attenuation effect of about 12dB in the low frequency band of 5-100Hz compared with the uncompressed control group. The second QZS platform compression can achieve an average attenuation effect of about 12dB in the low frequency band of 5-50Hz compared with the uncompressed control group. The third QZS platform compression can achieve an average attenuation effect of about 9.7dB in the low frequency band of 5-100Hz compared with the uncompressed control group.

[0038] As attached Figure 7b As shown in the figure, the vibration measurement test bench was used to test and verify the processed multi-stage stiffness vibration absorption and vibration isolation integrated device. The test results are basically consistent with the simulation calculation results. The first QZS platform compression and the second QZS platform compression can both show excellent vibration attenuation effects in the low frequency range of 10-310Hz compared with the uncompressed control group. Among them, the resonance peak of the first platform compression is attenuated from the original 2.1dB to -15.5dB compared with the control group.

[0039] According to the above data, it can be seen that the technical effects that the present invention can achieve are as follows: 1. Through the complementary effect of buckling stiffness superposition and contact enhancement behavior between multi-layer discrete structures, a variety of steady-state configurations can be obtained under different contact conditions, thereby realizing multiple QZS platform areas with obvious gradient differences in bearing capacity. The overall QZS working range of the device is equivalent to the superposition of QZS platform ranges of various steady-state configurations; 2. Through the optimization design of the structural form, the contact enhancement behavior of the multi-layer discrete structure after interlayer contact is utilized to realize a QZS platform with a large load-bearing capacity. The load-bearing capacity of the third QZS platform is 137.7N, which is nearly 5.5 times the load-bearing capacity of the first QZS platform of 21.1N. 3. With the help of the coupling interaction between the multi-layer discrete structures after the inter-layer contact, the equivalent damping loss factor of the vibration isolation device as a whole is significantly improved, and the energy loss capacity of the vibration isolation device is effectively enhanced; 4. The mechanical properties of each layer of discrete structure can be designed completely independently, and the mechanical properties of each layer of discrete structure after contact satisfy the linear superposition relationship. The complete decoupling relationship between the mechanical properties of each layer of discrete structure makes such structures more efficient, convenient and flexible to customize; 5. By symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, based on the design idea of ​​"absorption instead of isolation", a multi-stage stiffness vibration absorption-vibration isolation integrated device is constructed. The external frame is responsible for bearing, and the internal QZS type local resonance unit is responsible for vibration absorption. By adjusting the parameters of the external frame and the QZS local resonance unit respectively, the bearing capacity and vibration reduction effect of the overall device can be customized, and finally the bearing-vibration reduction integrated design under large bearing conditions is realized.

[0040] In summary, according to the above characteristics of a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device provided by the present invention, the vibration isolation device provided by the present invention can achieve excellent vibration isolation effect in a wide bandwidth range of the low frequency band on the basis of obtaining considerable bearing capacity. This device is a design strategy of a self-contact superposition complementary multi-stage multi-stable vibration isolation device proposed by analogy with the special multi-layer structure of plant petals. It utilizes the superposition complementary effect and contact enhancement behavior of the interlayer buckling stiffness of the multi-layer structure to obtain multiple quasi-zero stiffness platform areas with obvious gradient differences in bearing capacity. At the same time, with the help of the coupling interaction after the interlayer contact, the energy loss capacity is effectively improved, and the bearing capacity is improved. In addition, for ultra-large load application conditions, a design scheme based on "absorption instead of isolation" is proposed. By symmetrically arranging two self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage stiffness vibration absorption-vibration isolation integrated device is constructed. In summary, compared with the existing QZS vibration isolation device, the load-bearing capacity of this QZS vibration isolation device is significantly improved, and the working QZS platform is effectively widened, which can well meet the vibration reduction application requirements for low-frequency vibration reduction effect and reliable bearing strength in actual engineering.

[0041] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0042] In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution according to the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device, characterized in that: The invention comprises an outer layer structure (1), a middle layer structure (2), an inner layer structure (3) and a height-increasing structure (4); the outer layer structure (1), the middle layer structure (2) and the inner layer structure (3) are independent of each other and are connected and combined by the height-increasing structure (4) to form an integrated vibration isolation device.

2. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 1, characterized in that: The total height of the device is 103 mm, and the curved beam contours of the outer structure (1), the middle structure (2) and the inner structure (3) all satisfy the equation ,in x The values ​​range from -52.4 mm to 52.4 mm, -29.0 mm to 29.0 mm and -14.5 mm to 14.5 mm respectively. The straight beams of the outer structure (1), the middle structure (2) and the inner structure (3) are x The positive axis angles are 100° and 80° respectively.

3. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 2, characterized in that: The height of the portion where the height-enhancing structure (4) contacts the outer structure (1) is 32 mm, and the height of the portion where the height-enhancing structure (4) contacts the middle structure (2) is 11 mm.

4. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 1, characterized in that: By utilizing the complementary effect of the interlayer buckling stiffness superposition and the contact enhancement behavior of the outer layer structure (1), the middle layer structure (2) and the inner layer structure (3) after contact, multiple QZS platform areas with obvious gradient differences in bearing capacity are obtained, and multiple QZS platforms can achieve excellent low-frequency and wide-band vibration isolation effects.

5. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 1, characterized in that: By adjusting the geometric parameters of the vibration isolation device, including the in-plane thickness of the outer layer structure (1), the angle of the oblique straight beam of the middle layer structure (2), etc., it is possible to directly adjust the various QZS platform characteristics of the vibration isolation device, including the position of the QZS platform and the vibration isolation effect of the QZS platform.

6. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 1, characterized in that: Through theoretical model analysis, the elastic restoring force of the single-layer structure of the vibration isolation device F With displacement x There is a cubic function relationship without constant terms, that is, by reasonably adjusting the geometric parameter values ​​of the single-layer structure, the QZS characteristics can be achieved in the preset compression displacement range.

7. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 1, characterized in that: By symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage QZS type vibration absorption-vibration isolation integrated device is constructed, which is composed of two external frames (5) and a QZS type local resonance unit (6).

8. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 7, characterized in that: A gap is left between the two outer frames (5) in the initial state, and the internal QZS type local resonance unit (6) can achieve an expected compression state at a certain QZS platform position, thereby obtaining excellent low-frequency vibration reduction capability.

9. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 7, characterized in that: The load-bearing and vibration reduction functions of the device are designed independently. The two external frames (5) are responsible for load-bearing after contact closure, and the internal QZS type local resonance unit (6) is responsible for vibration absorption after reaching the pre-compression state. With the synergistic effect of the two parts of the structure, an integrated load-bearing and vibration reduction design can be achieved under large load conditions.

10. A self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device method, characterized in that: The method is based on a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to any one of claims 1 to 9, comprising: It can exhibit different steady-state configurations under different external loads. When the external load is small, the vibration isolation device is in the first QZS platform state with general bearing capacity. The first QZS platform can be used to effectively block the low-frequency and wide-band vibration energy. As the external load increases, the vibration isolation device successively reaches the second QZS platform state and the third QZS platform state with better bearing capacity. The second QZS platform and the third QZS platform can be used respectively to achieve excellent low-frequency and wide-band vibration isolation performance under high bearing capacity, and finally achieve low-frequency and wide-band vibration isolation effects under various low, medium and high bearing pressure states.

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