Self-contacting superimposed complementary multi-stable quasi-zero stiffness vibration isolation device and method

Abstract

The application discloses a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device and method, which is a self-contact superposition complementary multi-stage multi-stable vibration isolation device design strategy proposed by analogy with the special multi-layer structure of a plant petal. The device utilizes the superposition complementary action and contact enhancement behavior of the buckling stiffness between the multi-layer structure layers, can obtain multiple quasi-zero stiffness (QZS) platform regions with obvious gradient differences in bearing capacity, and each QZS platform can realize excellent low-frequency broadband vibration isolation effect. Meanwhile, with the help of the coupling interaction after the interlayer contact, the energy loss capacity is effectively improved, and the bearing capacity is improved. Compared with the existing QZS vibration isolation device, the QZS vibration isolation device has obvious improvement in bearing capacity, and the working QZS platform is effectively widened, so that the vibration reduction application requirements for low-frequency damping effect and reliable bearing strength in actual engineering can be well met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of passive vibration isolation, and particularly relates to a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device and method. BACKGROUND

[0002] Although the traditional linear vibration isolation system can realize vibration isolation in the medium and high frequency bands, the attenuation effect on low frequency vibration is very limited. According to the classical vibration isolation theory, if the vibration isolation effect of the system in the low frequency band is to be realized, the natural frequency of the system must be reduced, which will lead to the reduction of the stiffness of the system, the corresponding 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 the traditional linear vibration isolation technology. By reducing the dynamic stiffness of the vibration isolation system, the static stiffness of the system is improved, the natural frequency of the vibration isolation system is reduced, and the unique "high static and low dynamic" stiffness characteristics are exhibited. The vibration isolation system can reduce the force or displacement transmissibility, so that the vibration isolation system can realize excellent low-frequency vibration isolation effect under the premise of having certain 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 excessive bulk of the vibration isolation device, large installation space, great difficulty in manufacturing and assembling, and poor stability. Compared with the positive and negative stiffness component combination design method, the QZS structure can be realized by the compliant mechanism design method, which can realize the integration, lightweight, compactness and modularization of the QZS structure. However, the existing QZS structure designed by the compliant mechanism has poor bearing performance, and the obtained QZS platform area is narrow, which cannot stably and reliably realize the bearing-vibration isolation integrated design. Therefore, it is necessary to develop a new QZS structure design form to realize effective bearing-vibration isolation integrated design that can be used in engineering practice. SUMMARY

[0005] The application aims to overcome the shortcomings of the existing quasi-zero stiffness vibration isolation technology, and provides a self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device and method, which can realize excellent low-frequency wide-band vibration isolation effect on the basis of having considerable bearing capacity, and can obtain a wider QZS vibration isolation platform area.

[0006] In order to achieve the above-mentioned purpose, the application adopts the following technical solutions:

[0007] A self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device includes an outer layer structure, a middle layer structure, an inner layer structure and an increased height 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 increased height structure to form an integrated vibration isolation device.

[0008] 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.

[0009] A further improvement of the present invention is that the height of the portion of the heightened structure in contact with the outer structure is 32 mm, and the height of the portion of the heightened structure in contact with the middle structure is 11 mm.

[0010] A further improvement of the present invention is that, by utilizing the complementary effect of the interlayer buckling stiffness superposition and 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 all achieve excellent low-frequency and wide-band vibration isolation effects.

[0011] 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.

[0012] 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 is F and 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.

[0013] 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-isolation integrated device is constructed, which consists of two external frames and a QZS type local resonance unit.

[0014] 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 damping capability.

[0015] 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 load-bearing after contact and closure, 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.

[0016] 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:

[0017] 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 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, ultimately achieving low-frequency and wide-band vibration isolation effects under various low, medium and high bearing pressure conditions.

[0018] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0019] 1. Through the complementary effect of buckling stiffness superposition and contact enhancement behavior between multi-layer discrete structures, multiple steady-state configurations can be obtained under different contact conditions, thereby realizing multiple QZS platform regions with obvious gradient differences in load-bearing capacity, which is equivalent to the superposition of QZS platform intervals of various steady-state configurations;

[0020] 2. Through structural optimization and design, the contact enhancement behavior of multi-layer discrete structures after interlayer contact is utilized to achieve a QZS platform with a large load-bearing capacity;

[0021] 3. By leveraging the coupling interaction between the multi-layer discrete structures after inter-layer contact, the equivalent damping loss factor of the entire vibration isolation device is significantly improved, effectively enhancing the energy loss capacity of the vibration isolation device;

[0022] 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;

[0023] 5. By symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage QZS vibration absorption and isolation integrated device was constructed. Based on the design concept of "absorption instead of isolation", the external frame and internal QZS type local resonance unit are used to realize the load-bearing and vibration absorption functions respectively, which can realize the load-bearing and vibration reduction integrated design under large load conditions.

[0024] In summary, according to the above characteristics of a self-contact superimposed 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 frequency band of the low frequency band on the basis of obtaining considerable load-bearing capacity. This device is a design strategy of a self-contact superimposed complementary multi-stage multi-stable vibration isolation device proposed by analogy with the special multi-layer structure of plant petals. It utilizes the superimposed complementary effect and contact enhancement behavior of the buckling stiffness between layers of the multi-layer structure to obtain multiple quasi-zero stiffness platform areas with obvious gradient differences in load-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 load-bearing capacity is improved. In addition, for ultra-large load-bearing application conditions, a design scheme based on "absorption instead of isolation" is proposed. By symmetrically arranging two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage stiffness vibration absorption-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 QZS vibration isolation platform is effectively widened, which can well meet the vibration reduction application requirements for low-frequency vibration reduction effect and reliable load-bearing strength in actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The design idea of ​​self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device;

[0026] Figure 2 The five types of adjustable parameter distributions of the self-contact superposition complementary multistable quasi-zero stiffness vibration isolation device;

[0027] Figure 3 The simulation results of the quasi-static force-displacement compression curve of the self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device are shown;

[0028] Figure 4a Setting the constraints for dynamic analysis of the self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device;

[0029] Figure 4b The simulation results of the vibration isolation effect of the first QZS platform of the self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device are shown;

[0030] Figure 4c The simulation results of the vibration isolation effect of the second QZS platform of the self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device are shown;

[0031] Figure 4d The simulation results of the vibration isolation effect of the third QZS platform of the self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device are shown;

[0032] Figure 5aThe experimental test results of the quasi-static force-displacement compression curve of the self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device are shown;

[0033] Figure 5b The vibration isolation test results of the first and second QZS platforms of the self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device are shown.

[0034] Figure 6 The model of the "absorption instead of isolation" multi-stage stiffness vibration absorption-isolation integrated device and its principle diagram;

[0035] Figure 7a The simulation results of the vibration reduction effect of the multi-stage stiffness vibration absorption and isolation integrated device in the first QZS platform compression state, the second QZS platform compression state, and the third QZS platform compression state;

[0036] Figure 7b These are the experimental test results of the vibration reduction effect of the multi-stage stiffness vibration absorption and isolation integrated device in the compression state of the first QZS platform and the compression state of the second QZS platform. DETAILED DESCRIPTION

[0037] The technical solutions in the examples of implementation of the present invention are described below in conjunction with the relevant calculation and measurement results of the examples of implementation of the present invention in the accompanying drawings. Obviously, the examples of implementation described are only some examples of implementation of the present invention, not all examples of implementation. Based on the examples of implementation of the present invention, all other examples of implementation obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0038] Example 1

[0039] The present invention provides a self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device, which includes 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.

[0040] 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 portion between the heightened structure 4 and the outer structure 1 is 32 mm, and the height of the contact portion between the heightened structure 4 and the middle structure 2 is 11 mm.

[0041] In the embodiment, the interlayer buckling stiffness superposition complementary action and contact enhancement behavior of the outer layer structure 1, the middle layer structure 2 and the inner layer structure 3 after contact are utilized to obtain a plurality of QZS platform regions with obvious gradient difference in carrying capacity, and the plurality of QZS platforms can all achieve excellent low-frequency wide-band vibration isolation effect.

[0042] In the embodiment, the coupling interaction of the outer layer structure 1, the middle layer structure 2 and the inner layer structure 3 after contact merging not only significantly improves the carrying capacity of the device, but also significantly improves the strain energy density of the overall structure of the device, and effectively enhances the damping loss capacity of the device for vibration energy.

[0043] In the embodiment, by adjusting the geometric parameters of the vibration isolation device, including the in-plane thickness of the outer layer structure 1 and the oblique beam angle of the middle layer structure 2, the characteristics of each QZS platform 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.

[0044] In the embodiment, through theoretical model analysis, the elastic restoring force of the single-layer structure of the vibration isolation device F and displacement x is a cubic function without constant term, that is, by reasonably adjusting the geometric parameter values of the single-layer structure, the QZS characteristics can be realized in the preset compression displacement interval.

[0045] In the embodiment, the outer layer structure 1, the middle layer structure 2 and the inner layer structure 3 are completely independent and adjustable, the design parameters of each layer structure can be independently determined as needed, and the coupling mechanical characteristics of each layer structure after mutual contact satisfy the linear superposition relationship.

[0046] In the embodiment, by symmetrically arranging two self-contacting superposition complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage QZS type vibration absorption-isolation integrated device is constructed, which is composed of two external frames 5 and one QZS type local resonance unit 6.

[0047] In the embodiment, the two external frames 5 have a gap in the initial state, and the size of the gap can be customized designed, so that when the two external frames 5 are in contact and closed, the internal QZS type local resonance unit 6 can reach the expected compression state at a certain QZS platform position, thereby obtaining excellent low-frequency vibration damping capacity.

[0048] In the embodiment, the carrying and damping functions of the device are designed independently, the two external frames 5 are responsible for carrying after contact and closure, and the internal QZS type local resonance unit 6 is responsible for vibration absorption after reaching the pre-compression state, and under the synergistic action of the two parts, the carrying-damping integrated design under large carrying working conditions can be effectively realized.

[0049] Embodiment 2

[0050] The application provides a self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device method, which comprises the following steps:

[0051] The vibration isolation device can exhibit different stable states under different external loads, and when the external load is small, the vibration isolation device is in a first QZS platform state with general load-carrying capacity, and the first QZS platform can be used to effectively block low-frequency wide-band vibration energy; as the external load increases, the vibration isolation device sequentially reaches a second QZS platform state and a third QZS platform state with better load-carrying capacity, and the second QZS platform and the third QZS platform can be used to realize excellent low-frequency wide-band vibration isolation performance under high load-carrying capacity, and finally realize low-frequency wide-band vibration isolation effect under low, medium and high load pressure states.

[0052] Embodiment 3

[0053] The self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device provided by the application is composed of an outer layer structure 1, a middle layer structure 2, an inner layer structure 3 and a heightening structure 4. Two self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices are symmetrically arranged to construct a multi-stage QZS type vibration absorption and isolation integrated device, which comprises two external frames 5 and a QZS type local resonance unit 6.

[0054] (I) Design and experimental verification of self-contact superimposed complementary multi-stable quasi-zero stiffness vibration isolation device

[0055] Inspired by the multi-layer petal structure in nature, a new self-contact superimposed complementary multi-stable QZS vibration isolation device is proposed by equivalent and optimization of the original petal structure, as shown in the accompanying Figure 1 The vibration isolation device finally obtained through optimization is composed of a deformed part made of TPU material and an auxiliary part made of aluminum alloy material. The deformed part includes three layers of discrete structures, i.e., an outer layer, a middle layer and an inner layer, and the deformed part obtains the expected multiple QZS platforms with different load-carrying capacities through deformation contact. The auxiliary part mainly provides a larger deformation working space for the discrete structures. The main design parameters of the vibration isolation device include the thickness of the outer layer B1, the thickness of the middle layer B2, the thickness of the inner layer B3, the distance between the outer layer and the middle layer H1 and the distance between the middle layer and the inner layer H2, as shown in the accompanying Figure 2 As an implementation example, a multi-layer QZS vibration isolation device is designed, the thickness of the outer layer B1, the thickness of the middle layer B2 and the thickness of the inner layer B3 are all 20 mm, the distance between the outer layer and the middle layer H1 is 30 mm, and the distance between the middle layer and the inner layer H2 is 20 mm. The quasi-static force-displacement compression curve is calculated and shown in the accompanying Figure 3As shown in the figure, this type of vibration isolation device can obtain three QZS platforms with significantly different load capacities in three stable configurations: the first stable QZS platform with a load capacity of 21.1 N, the second stable QZS platform with a load capacity of 107.1 N, and the third stable QZS platform with a load capacity of 137.7 N. This verifies the feasibility of this type of vibration isolation device structure to achieve a high-load-bearing, wide QZS platform design.

[0056] 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 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 compressive displacement in the Z axis 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 swept frequency acceleration excitation in the positive direction of the Z axis is applied. At the same time, acceleration input points A are set on the bottom and top surfaces of the device respectively. in and acceleration output point A out , by calculating the vibration acceleration transmission loss T=20lg (A out / A in ) to measure the vibration isolation effect of the vibration isolation device.

[0057] 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 As shown. 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 significant 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 begins to show vibration isolation effect at around 18.2Hz, and the optimal vibration isolation effect of 26.9dB is achieved 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 entire frequency band of 5-500Hz is negative, which means that it can achieve excellent vibration isolation effect for vibration energy in the entire frequency band of 5-500Hz, with the optimal vibration isolation effect of 31.1dB being achieved near 317.0Hz.

[0058] As attached Figure 5a As shown in the figure, the performance of the processed vibration isolation device sample 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 test results also show that this type of vibration isolation device can produce three QZS platforms with obvious gradient differences in load capacity, and the experimental test curve basically coincides with the simulation curve. Figure 5b As shown in the figure, the vibration isolation effect of multiple QZS platforms of the vibration isolation device prototype was tested and verified using a vibration measurement test bench. Due to limited experimental conditions, only the first and second QZS platforms were tested for vibration isolation. The test results were generally consistent with the simulation results. In summary, combined with the static and dynamic analysis results of the vibration isolation device, it is demonstrated that this type of device can produce multiple QZS platforms with significantly different load-bearing capacities. Each QZS platform can exhibit excellent vibration isolation effect for low-frequency broadband vibration energy below 500Hz, verifying the feasibility of realizing an integrated load-bearing and vibration isolation design through this multi-layer self-contact superimposed complementary structure.

[0059] (II) Design and experimental verification of a multi-stage stiffness vibration absorption and isolation integrated device using absorption instead of isolation

[0060] 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 consists of an external load-bearing frame and a QZS-type local resonance unit. The QZS-type local resonance unit is composed of two mirror-symmetrically arranged self-contact superposition complementary multistable quasi-zero stiffness vibration isolation devices. By appropriately adjusting the reserved distance between the external load-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 intended design, and the two self-contact superposition complementary multistable quasi-zero stiffness vibration isolation devices are both in a certain QZS platform position. In other words, the equivalent stiffness of the local resonance unit "spring-oscillator" system is approximately zero, which can achieve effective dissipation of low-frequency vibration energy.

[0061] 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 compressed state of the first QZS platform, the second QZS platform, and the third QZS platform was calculated respectively. The calculation results show that under the compressed state of the three QZS platforms, the "absorption instead of isolation" multi-stage stiffness vibration absorption and isolation integrated device can achieve good vibration isolation effect for low-frequency broadband vibration energy in the frequency range of 5-355Hz. Among them, the compression of the first QZS platform can achieve an average attenuation effect of approximately 12dB in the low-frequency range of 5-100Hz compared to the uncompressed control group. The compression of the second QZS platform can achieve an average attenuation effect of approximately 12dB in the low-frequency range of 5-50Hz compared to the uncompressed control group. The compression of the third QZS platform can achieve an average attenuation effect of approximately 9.7dB in the low-frequency range of 5-100Hz compared to the uncompressed control group.

[0062] As attached Figure 7b As shown in the figure, experimental testing and verification of the fabricated multi-stage stiffness integrated vibration absorption and isolation device was conducted using a vibration measurement test bench. The test results were generally consistent with the simulation results. Both the first and second QZS platform compressions demonstrated excellent vibration attenuation in the low-frequency range of 10-310 Hz compared to the uncompressed control group. Specifically, the first platform compression reduced the resonance peak from 2.1 dB to -15.5 dB compared to the control group.

[0063] According to the above data, it can be seen that the technical effects that the present invention can achieve are as follows:

[0064] 1. Through the complementary effect of buckling stiffness superposition and contact enhancement behavior between multi-layer discrete structures, multiple steady-state configurations can be obtained under different contact conditions, thereby realizing multiple QZS platform areas with significantly different load-bearing capacities. The overall QZS working range of the device is equivalent to the superposition of the QZS platform ranges of various steady-state configurations.

[0065] 2. Through the way of structural form optimization design, the contact enhancement behavior of the multi-layer discrete structure after interlayer contact is utilized to realize the QZS platform with large bearing capacity, the bearing capacity of the third QZS platform is 137.7N, which is about 5.5 times of the bearing capacity of the first QZS platform 21.1N;

[0066] 3. With the coupling interaction of the multi-layer discrete structure after interlayer contact, the equivalent damping loss factor of the vibration isolation device is obviously improved, and the energy loss capacity of the vibration isolation device is effectively enhanced;

[0067] 4. The mechanical properties of each layer of discrete structure can be completely independently designed, and the mechanical properties of each layer of discrete structure after contact meet the linear superposition relationship, and the complete decoupling relationship of the mechanical properties between each layer of discrete structure makes this kind of structure can be more efficient, more convenient and more flexible customized design;

[0068] 5. By symmetrically arranging two self-contacting superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, based on the design idea of "replacing isolation with absorption", a multi-stage stiffness vibration absorption-isolation integrated device is constructed, the external frame is responsible for bearing, and the internal QZS local resonance unit is responsible for vibration absorption, by adjusting the parameters of the external frame and the QZS local resonance unit respectively, the customized design of the bearing capacity and the damping effect of the overall device can be realized, and finally the bearing-damping integrated design under large bearing working condition is realized.

[0069] In summary, according to the above characteristics of the self-contacting superimposed complementary multi-stable quasi-zero stiffness vibration isolation device provided by the application, the vibration isolation device provided by the application can realize excellent vibration isolation effect in a wide frequency band in the low frequency band on the basis of obtaining considerable bearing capacity. This device is a self-contacting superimposed complementary multi-stage multi-stable vibration isolation device design strategy proposed by analogy with the special multi-layer structure of plant petals. It utilizes the superimposed complementary action and contact enhancement behavior of the buckling stiffness of the multi-layer structure, and can obtain multiple quasi-zero stiffness platform regions with obvious gradient difference in bearing capacity. At the same time, with the coupling interaction after interlayer contact, the energy loss capacity is effectively improved, and the bearing capacity is also improved. In addition, for the super large bearing application working condition, a design scheme based on "replacing isolation with absorption" is proposed, by symmetrically arranging two self-contacting superimposed complementary multi-stable quasi-zero stiffness vibration isolation devices, a multi-stage stiffness vibration absorption-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 obviously improved, the working QZS platform is effectively widened, and the vibration reduction application requirements for low frequency damping effect and reliable bearing strength in actual engineering can be well met.

[0070] 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 that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from all points of view, the embodiments should be regarded as illustrative and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and range of equivalents of the claims are included in the present invention. Any reference signs in the claims should not be construed as limiting the claim to which they relate.

[0071] In addition, it should be understood that although this specification describes the embodiments, not every embodiment contains only one independent technical solution. This description is for clarity only. Those skilled in the art should consider the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for the purpose of illustrating the technical concept of the present invention and cannot be used to limit the scope of protection of the present invention. Any changes made based on the technical solution in accordance with the technical concept proposed by the present invention fall within the scope of protection 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 device comprises an outer layer structure (1), a middle layer structure (2), an inner layer structure (3) and a heightening structure (4), wherein 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; wherein the heightening structure (4) is arranged at the bottom, and the outer layer structure (1), the middle layer structure (2) and the inner layer structure (3) are arranged in sequence from the outside to the inside, and the bottoms are respectively connected to the heightening structure (4); The outer layer structure (1), the middle layer structure (2) and the inner layer structure (3) all include a curved beam and oblique straight beams connected to both sides of the curved beam, and the bottom of each oblique straight beam is connected to the height-increasing structure (4). 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 two 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 portion of the height-increasing structure (4) with the outer structure (1) is 32 mm, and the height of the contact portion with the middle structure (2) is 11 mm.

2. 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 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.

3. 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) and the angle of the oblique straight beam of the middle layer structure (2), 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.

4. 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 and 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.

5. 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-isolation integrated device is constructed, which consists of two external frames (5) and a QZS type local resonance unit (6).

6. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 5, 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 the expected compression state at a certain QZS platform position, thereby obtaining excellent low-frequency vibration damping capability.

7. The self-contact superposition complementary multi-stable quasi-zero stiffness vibration isolation device according to claim 5, 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. Under 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.

8. 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 7, 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 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, ultimately achieving low-frequency and wide-band vibration isolation effects under various low, medium and high bearing pressure conditions.

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