A self-adjusting quasi-zero stiffness vibration isolator

Abstract

The present invention discloses a self-adjusting quasi-zero stiffness vibration isolator, comprising an airbag positive stiffness structure, a spring pull rod negative stiffness structure and a symmetrical permanent magnet stabilizing structure; the spring pull rod negative stiffness structure and the symmetrical permanent magnet stabilizing structure are alternately arranged along the circumferential direction of the airbag positive stiffness structure; the spring pull rod negative stiffness structure is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure, and the symmetrical permanent magnet stabilizing structure is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure. The beneficial effects of the present invention are as follows: the vibration isolator of the present invention can adjust the stability and positive and negative stiffness range of the vibration isolator according to different objects to be isolated, so as to adapt to different objects to be isolated and different vibration systems, thereby greatly improving the low-frequency vibration isolation bandwidth and applicable range of the quasi-zero stiffness vibration isolator, and has the characteristics of strong adaptability, fast response, low bandwidth and high stability.

Description

Technical Field

[0001] The present invention relates to the field of vibration isolation technology, in particular to a self-adjusting quasi-zero stiffness vibration isolator. Background Art

[0002] With the development of ultra-precision machining and manufacturing technology, the harm of low-frequency and ultra-low-frequency vibration has become increasingly prominent and obvious. The vibration isolation effect is achieved in the frequency band of times the natural frequency, so it is difficult to achieve low-frequency bandwidth vibration isolation performance. Quasi-zero stiffness isolators have a "high static and low dynamic" nonlinear stiffness characteristic, that is, they have high stiffness under static load to provide static stability; and have a low stiffness close to zero under dynamic load to broaden the low-frequency vibration isolation performance.

[0003] Quasi-zero stiffness isolators are effective instruments for isolating low and ultra-low frequencies. However, existing quasi-zero stiffness isolators have two main drawbacks: unadjustable stiffness and poor load-bearing stability. The unadjustable stiffness results in different equipment requiring different isolators, significantly reducing the applicability of quasi-zero stiffness isolators and increasing their cost. Poor load-bearing stability causes equipment to vibrate irregularly, leading to excitation coupling from the vibration source, making it difficult to identify the direction and type of interfering excitation, and reducing the vibration isolation performance of the isolator. Currently, most vibration isolation structures use a contact mechanism to increase stiffness and improve stability. However, the excitation can also be transmitted to the equipment or the ground through the contact mechanism, significantly reducing the vibration isolation transmission rate and affecting the low-frequency vibration isolation performance. Summary of the Invention

[0004] The object of the present invention is to provide a self-adjusting quasi-zero stiffness vibration isolator with adjustable stiffness, in view of the deficiencies in the prior art.

[0005] The technical solution adopted by the present invention is: a self-adjusting quasi-zero stiffness vibration isolator, comprising an airbag positive stiffness structure, a spring pull rod negative stiffness structure and a symmetrical permanent magnet stabilization structure;

[0006] The spring pull rod negative stiffness structure and the symmetrical permanent magnet stabilization structure are alternately arranged along the circumferential direction of the airbag positive stiffness structure; the spring pull rod negative stiffness structure is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure, and the symmetrical permanent magnet stabilization structure is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure.

[0007] According to the above scheme, the airbag positive stiffness structure includes an upper cover plate, a lower cover plate, and an airbag group formed by at least two airbags connected in series up and down; the upper end of the airbag located at the upper part is connected to the upper cover plate, and the lower end of the airbag located at the lower part is connected to the lower cover plate; the two adjacent airbags are connected by a middle connecting plate; the airbag is provided with an inflation port.

[0008] According to the above scheme, the upper cover plate, lower cover plate and middle connecting plate are all hexagonal plates, and the edges of each plate body correspond to each other up and down; two connecting bolt plates for connecting to the negative stiffness structure of the spring pull rod are respectively provided on the three spaced edges of the upper cover plate and the lower cover plate, and the connecting bolt plates on the corresponding edges of the upper cover plate and the lower cover plate also correspond to each other up and down; the middle connecting plate is provided with a connecting ear plate for connecting to the negative stiffness structure of the spring pull rod.

[0009] According to the above scheme, the self-adjusting spring pull rod negative stiffness structure includes two parallel arranged negative stiffness components, and the two negative stiffness components are located on the outside of the same side of the middle connecting plate; the negative stiffness component includes a cross, a mechanical linear spring, an upper pull rod and a lower pull rod; the cross is arranged on the outside of the middle connecting plate, and the inner end of the horizontal section of the cross is connected to one end of the mechanical linear spring, and the other end of the mechanical linear spring is connected to the middle connecting plate; the upper end of the vertical section of the cross is hinged to the lower end of the upper pull rod, and the upper end of the upper pull rod is hinged to the upper cover plate; the lower end of the vertical section of the cross is hinged to the upper end of the lower pull rod, and the lower end of the lower pull rod is hinged to the lower cover plate.

[0010] According to the above scheme, in each negative stiffness component, there are two upper pull rods, which are arranged in parallel. The lower ends of the two upper pull rods are connected to the upper end of the vertical section of the cross through the same pin, and the upper ends of the two upper pull rods are connected to the connecting bolt plate of the upper cover through the same pin; there are two lower pull rods, which are arranged in parallel. The upper ends of the two lower pull rods are connected to the lower end of the vertical section of the cross through the same pin, and the lower ends of the two lower pull rods are connected to the connecting bolt plate of the lower cover through the same pin.

[0011] According to the above solution, the symmetrical permanent magnet stabilization structure is arranged on the periphery of the airbag positive stiffness structure, and is alternately arranged with the respective adjustment spring pull rod negative stiffness structures.

[0012] According to the above scheme, the symmetrical permanent magnet stabilization structure includes a fixed permanent magnet assembly, a lifting permanent magnet assembly and a driving assembly; the fixed permanent magnet assembly has two groups, which are respectively installed on the outer sides of the upper cover plate and the lower cover plate through connecting seats; the lifting permanent magnet assembly has two groups, which are respectively arranged at the upper and lower parts of the driving assembly; the lifting permanent magnet assembly located at the upper part is arranged in pairs with the fixed permanent magnet assembly on the outer side of the upper cover plate; the lifting permanent magnet assembly located at the lower part is arranged in pairs with the fixed permanent magnet assembly on the outer side of the lower cover plate; the driving assembly is fixed on the middle connecting plate, and the driving ends of the driving assembly are respectively connected to the two lifting permanent magnet assemblies; the driving assembly can drive the two lifting permanent magnet assemblies to move up and down, thereby changing the air gap between them and the corresponding fixed permanent magnet assemblies.

[0013] According to the above scheme, the structure of the fixed permanent magnet assembly and the lifting permanent magnet assembly is the same, both including a mounting frame and a permanent magnet arranged in the mounting frame; wherein the permanent magnet of the fixed permanent magnet assembly and the permanent magnet of its corresponding lifting permanent magnet assembly are directly opposite to each other and have the same polarity; the mounting frame of the fixed permanent magnet assembly is connected to the upper cover plate or the lower cover plate, and the mounting frame of the lifting permanent magnet assembly is connected to the drive assembly.

[0014] According to the above scheme, the driving assembly includes a base, and a driving mechanism provided at the upper and lower parts of the base; the base is connected to the middle connecting plate; the driving mechanism includes a horizontal threaded rod, two moving blocks and two lifting rods; the threaded rod is rotatably mounted on the base, and the two moving blocks are threadedly connected to the threaded rod and are respectively located at the two ends of the threaded rod; one end of the two lifting rods is hinged to the two moving blocks respectively, and the other end of the two lifting rods is hinged to the mounting frame of the lifting permanent magnet assembly.

[0015] According to the above solution, the mounting frame of the lifting permanent magnet assembly is provided with an ear plate, which is connected to the end of the lifting rod through a pin; the end of the threaded rod is provided with a knob for driving the threaded rod to rotate.

[0016] The beneficial effects of the present invention are:

[0017] 1. The vibration isolator of the present invention has quasi-zero stiffness regardless of whether it is installed above or below. The stability and positive and negative stiffness range of the vibration isolator can be adjusted according to different objects to be isolated to adapt to different objects to be isolated and different vibration systems, greatly improving the low-frequency vibration isolation bandwidth and applicable range of the quasi-zero stiffness vibration isolator.

[0018] 2. The present invention combines a double-layer airbag and a spring connecting rod to achieve the stiffness adjustment function of the quasi-zero stiffness vibration isolator by changing the air pressure in the airbag and the automatic adjustment characteristics of the spring connecting rod mechanism. The present invention designs a non-contact, variable-distance permanent magnet structure, which can greatly increase the stability of the vibration isolator without affecting its vibration isolation transmission rate, thereby improving its vibration isolation performance. The permanent magnet structure mechanism can also adjust the relative distance of the permanent magnets according to the type of vibration-isolated equipment, change the stiffness required for stability, and achieve the load-bearing stability of different vibration-isolated objects.

[0019] 3. The self-adjusting spring pull rod negative stiffness structure designed in the present invention realizes the self-adjusting function of positive and negative stiffness without the need for horizontal alignment, and simplifies the negative stiffness structure. The negative stiffness structure and the permanent magnet structure are distributed in an alternating interval, which has the advantages of structural stability and convenient decoupling.

[0020] 4. The present invention has the characteristics of simple structure, reliable operation, strong stability, low vibration transmission rate, fast response, low bandwidth and easy control. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1It is a structural diagram of a specific embodiment of the present invention.

[0022] Figure 2 Schematic diagram of the positive stiffness structure of the airbag in this embodiment.

[0023] Figure 3 Schematic diagram of the upper cover.

[0024] Figure 4 Schematic diagram of the middle connecting plate.

[0025] Figure 5 Schematic diagram of a single negative stiffness component in this embodiment.

[0026] Figure 6 Schematic diagram of the symmetrical permanent magnet stabilization structure in this embodiment.

[0027] Figure 7 Schematic diagram of the structure for fixing the permanent magnet assembly.

[0028] Figure 8 A schematic diagram of the drive assembly.

[0029] Among them: 1. Airbag positive stiffness structure; 1-1. Upper cover plate; 1-2. Lower cover plate; 1-3. Airbag; 1-4. Middle connecting plate; 1-5. Connecting bolt plate; 1-6. Connecting ear plate; 1-7. Inflation port; 2. Spring pull rod negative stiffness structure; 2-1. Cross; 2-2. Upper pull rod; 2-3. Lower pull rod; 2-4. Spring; 3. Symmetrical permanent magnet stabilization structure; 3-1. Fixed permanent magnet assembly; 3-2. Lifting permanent magnet assembly; 3-3. Driving mechanism; 3-3-1. Base; 3-3-2. Threaded rod; 3-3-3. Moving block; 3-3-4. Lifting rod; 3-4. Connecting seat; 3-5. Mounting frame; 3-6. Permanent magnet. DETAILED DESCRIPTION

[0030] In order to better understand the present invention, the present invention is further described below with reference to the accompanying drawings and specific embodiments.

[0031] like Figure 1 A self-adjusting quasi-zero stiffness vibration isolator shown includes an airbag positive stiffness structure 1, a spring pull rod negative stiffness structure 2, and a symmetrical permanent magnet stabilization structure 3;

[0032] The spring pull rod negative stiffness structure 2 and the symmetrical permanent magnet stabilization structure 3 are alternately arranged along the circumferential direction of the airbag positive stiffness structure 1; the spring pull rod negative stiffness structure 2 is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure 1, and the symmetrical permanent magnet stabilization structure 3 is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure 1.

[0033] In this embodiment, three groups of the spring pull rod negative stiffness structures 2 and the symmetrical permanent magnet stabilization structures 3 are provided respectively, and the spring pull rod negative stiffness structures 2 and the symmetrical permanent magnet stabilization structures 3 are alternately arranged along the periphery of the airbag positive stiffness structure 1 .

[0034] Preferably, if Figure 1 As shown, the airbag positive stiffness structure 1 includes an upper cover plate 1-1, a lower cover plate 1-2, and an airbag 1-3 group formed by at least two airbags 1-3 connected in series up and down; the upper end of the airbag 1-3 located at the upper part is connected to the upper cover plate 1-1, and the lower end of the airbag 1-3 located at the lower part is connected to the lower cover plate 1-2; the two adjacent airbags 1-3 are connected by a middle connecting plate 1-4; the airbag 1-3 is provided with an inflation port 1-7.

[0035] In the present invention, the airbag positive stiffness structure 1 serves as the primary stiffness structure, providing positive stiffness for the vibration isolator. The upper cover plate 1-1, lower cover plate 1-2, and central connecting plate 1-4 are arranged parallel and spaced apart in height. Two airbags 1-3 are positioned one above the other and independently pressurized, with the inflation port 1-7 for the upper airbag 1-3 located on the upper cover plate 1-1 and the inflation port 1-7 for the lower airbag 1-3 located on the lower cover plate 1-2. The airbag positive stiffness structure 1 achieves varying load capacities and allows for hovering at different positions on the central connecting plate 1-4 through the series arrangement of the airbags 1-3 and the pressure differential between the upper and lower parts.

[0036] In the present invention, Figures 2-4 As shown, the upper cover plate 1-1, the lower cover plate 1-2 and the middle connecting plate 1-4 are all hexagonal plates, and the edges of each plate body correspond to each other up and down; two connecting bolt plates 1-5 for connecting to the spring pull rod negative stiffness structure 2 are respectively provided at the three spaced edges of the upper cover plate 1-1 and the lower cover plate 1-2, and the connecting bolt plates 1-5 on the corresponding edges of the upper cover plate 1-1 and the lower cover plate 1-2 also correspond to each other up and down; the middle connecting plate 1-4 is provided with a connecting ear plate 1-6 for connecting to the spring pull rod negative stiffness structure 2.

[0037] Preferably, if Figure 5As shown, the self-adjusting spring pull rod negative stiffness structure 2 includes two parallel arranged negative stiffness components, and the two negative stiffness components are located on the outside of the same side of the middle connecting plate 1-4; the negative stiffness component includes a cross 2-1, a mechanical linear spring 2-4, an upper pull rod 2-2 and a lower pull rod 2-3; the cross 2-1 is arranged on the outside of the middle connecting plate 1-4, and the inner end of the horizontal section of the cross 2-1 is connected to one end of the mechanical linear spring 2-4, and the other end of the mechanical linear spring 2-4 is connected to the connecting ear plate 1-6 of the middle connecting plate 1-4; the upper end of the vertical section of the cross 2-1 is connected to the middle connecting plate 1-4 by a roller The movable bearing and the pin are hinged to the lower end of the upper pull rod 2-2 (specifically, the upper end of the vertical section of the cross 2-1 and the lower end of the upper pull rod 2-2 are respectively provided with mounting holes, a rolling bearing is provided in each mounting hole, and the inner rings of the two rolling bearings are adapted to the same pin), the upper end of the upper pull rod 2-2 is hinged to the connecting bolt plate 1-5 on the upper cover plate 1-1 through the rolling bearing and the pin; the lower end of the vertical section of the cross 2-1 is hinged to the upper end of the lower pull rod 2-3 through the rolling bearing and the pin, and the lower end of the lower pull rod 2-3 is hinged to the connecting bolt plate 1-5 on the lower cover plate 1-2 through the rolling bearing and the pin.

[0038] In each negative stiffness assembly of the present invention, there are two upper tie rods 2-2, arranged in parallel. The lower ends of the two upper tie rods 2-2 are connected to the upper end of the vertical section of the cross 2-1 via a common pin, and the upper ends of the two upper tie rods 2-2 are connected to the connecting bolt plate 1-5 of the upper cover plate 1-1 via a common pin. Similarly, there are two lower tie rods 2-3, arranged in parallel. The upper ends of the two lower tie rods 2-3 are connected to the lower end of the vertical section of the cross 2-1 via a common pin, and the lower ends of the two lower tie rods 2-3 are connected to the connecting bolt plate 1-5 of the lower cover plate 1-2 via a common pin. The connecting bolt plates 1-5 of the upper cover plate 1-1 and the lower cover plate 1-2 connected to the same negative stiffness assembly correspond in position.

[0039] In the present invention, three self-adjusting spring pull rod negative stiffness structures 2 are evenly distributed around the airbag positive stiffness structure 1, such as Figure 1 As shown, the self-adjusting spring-tie rod negative stiffness structure 2 utilizes two sets of negative stiffness components, increasing negative stiffness while improving structural stability. One end of the upper and lower tie rods 2-2 and 2-3 is hinged to the upper and lower cover plates 1-2 via rolling bearings and pins, while the other end is similarly hinged to the cross 2-1. At different airbag 1-3 heights, the tie rods drive the spring equilibrium position to shift, achieving self-adjusting negative stiffness. The cross 2-1 is connected to the central connecting plate 1-4 via a mechanical linear spring 2-4, eliminating the need for horizontal alignment between the spring-tie rod structure and the airbag 1-3, achieving quasi-zero stiffness.

[0040] Preferably, the symmetrical permanent magnetic stabilization structure 3 is arranged on the periphery of the airbag positive stiffness structure 1 and is alternately arranged with the respective spring pull rod negative stiffness structures 2 .

[0041] In the present invention, Figure 6 As shown, the symmetrical permanent magnet stabilization structure 3 includes a fixed permanent magnet component 3-1, a lifting permanent magnet component 3-2 and a driving component 3-3;

[0042] There are two groups of fixed permanent magnet assemblies 3-1, which are respectively installed on the outer sides of the upper cover plate 1-1 and the lower cover plate 1-2 through the connecting base 3-4;

[0043] There are two groups of lifting permanent magnet assemblies 3-2, which are respectively arranged at the upper and lower parts of the driving assembly 3-3; the lifting permanent magnet assembly 3-2 located at the upper part is paired with the fixed permanent magnet assembly 3-1 on the outer side of the upper cover plate 1-1; the lifting permanent magnet assembly 3-2 located at the lower part is paired with the fixed permanent magnet assembly 3-1 on the outer side of the lower cover plate 1-2; the driving assembly 3-3 is fixed on the middle connecting plate 1-4, and the driving end of the driving assembly 3-3 is respectively connected to the two lifting permanent magnet assemblies 3-2; the driving assembly 3-3 can drive the two lifting permanent magnet assemblies 3-2 to move up and down, changing the air gap between them and the corresponding fixed permanent magnet assemblies 3-1.

[0044] In the present invention, the fixed permanent magnet assembly 3-1 outside the lower cover plate 1-2 and the lifting permanent magnet assembly 3-2 above it (that is, located at the lower part of the driving assembly 3-3) are arranged in pairs; the fixed permanent magnet assembly 3-1 outside the upper cover plate 1-1 and the lifting permanent magnet assembly 3-2 below it (that is, located at the upper part of the driving assembly 3-3) are arranged in pairs.

[0045] Preferably, the fixed permanent magnet assembly 3-1 and the lifting permanent magnet assembly 3-2 have the same structure, both including a mounting frame 3-5 and a permanent magnet 3-6 arranged in the mounting frame 3-5; wherein the permanent magnet 3-6 of the fixed permanent magnet assembly 3-1 and its corresponding permanent magnet 3-6 of the lifting permanent magnet assembly 3-2 are opposite to each other up and down and have the same polarity; the mounting frame 3-5 of the fixed permanent magnet assembly 3-1 is connected to the upper cover plate 1-1 or the lower cover plate 1-2 (can be bolted), and the mounting frame 3-5 of the lifting permanent magnet assembly 3-2 is connected to the driving assembly 3-3 (can be bolted).

[0046] Preferably, the driving assembly 3-3 includes a base 3-3-1, and driving assemblies 3-3 provided at the upper and lower parts of the base 3-3-1; the base 3-3-1 is connected to the middle connecting plate 1-4; the driving assembly 3-3 includes a horizontal threaded rod 3-3-2, two moving blocks 3-3-3 and two lifting rods 3-3-4; the threaded rod 3-3-2 is rotatably mounted on the base 3-3-1, and the two moving blocks 3-3-3 are threadedly connected to the threaded rod 3-3-2 (the moving blocks 3-3-3 are provided with threaded holes adapted to the threaded rod 3-3-2), and are respectively located at both ends of the threaded rod 3-3-2; one end of the two lifting rods 3-3-4 is hinged to the two moving blocks 3-3-3, respectively, and the other end of the two lifting rods 3-3-4 is hinged to the mounting frame 3-5 of the lifting permanent magnet assembly 3-2 (hinged at the same position as the mounting frame 3-5).

[0047] In the present invention, an ear plate is provided on the mounting frame 3-5 of the lifting permanent magnet assembly 3-2, and the ear plate is connected to the end of the lifting rod 3-3-4 through a pin; the end of the threaded rod 3-3-2 is provided with a knob for driving the threaded rod 3-3-2 to rotate.

[0048] In the present invention, two groups of driving components 3-3 are respectively provided at the upper and lower parts of the base 3-3-1. The driving component 3-3 drives the threaded rod 3-3-2 to rotate through the knob, and the two moving blocks 3-3-3 move toward or away from each other along the axis of the threaded rod 3-3-2. The ends of the two lifting rods 3-3-4 (the ends connected to the moving blocks 3-3-3) move closer or farther away accordingly, and the lifting permanent magnet assembly 3-2 connected to the two lifting rods 3-3-4 rises and falls accordingly, thereby realizing the up and down movement of the permanent magnet in the lifting permanent magnet assembly 3-2, and changing the air gap between the permanent magnet of the lifting permanent magnet assembly 3-2 and the corresponding permanent magnet of the fixed permanent magnet assembly 3-1.

[0049] The present invention adopts a structure that is symmetrical in the upper and lower parts and arranged at alternating intervals on the periphery; the symmetrical structure can realize the function of arbitrary installation suspension, and the structure arranged at alternating intervals on the periphery can realize the function of maximum decoupling. The airbag positive stiffness structure 1 is the positive stiffness main body, and the self-adjusting spring pull rod negative stiffness structure 2 and the symmetrical permanent magnet stabilization structure 3 are auxiliary structures, one provides negative stiffness and the other provides stabilizing force. The self-adjusting spring pull rod negative stiffness structure 2 is connected in parallel with the airbag positive stiffness structure 1 to form a stiffness parallel mode of interaction to form a quasi-zero stiffness characteristic. The airbags 1-3 in the airbag positive stiffness structure 1 are filled with gases of different pressures to achieve different stiffness changes; as the air pressure of the upper and lower airbags 1-3 is different, the middle connecting plate 1-4 will automatically move to the equilibrium position. At this time, the spring pull rod negative stiffness structure 2 "in parallel" with it changes with the height of the airbag 1-3. Under the action of the mechanical linear spring 2-4, the angle of the pull rod in the spring pull rod negative stiffness structure 2 is automatically adjusted to achieve the purpose of self-adjusting negative stiffness. Therefore, by changing the air pressure of airbags 1-3, a quasi-zero stiffness vibration isolator with different loads can be realized.

[0050] In the present invention, the symmetrical permanent magnet stabilization structure 3 is an auxiliary structure; the two sets of lifting permanent magnet assemblies form a symmetrical adjustable permanent magnet structure with the upper and lower fixed permanent magnet assemblies respectively. According to different bearing capacities, the air gap between the permanent magnets of the lifting permanent magnet assembly 3-2 and its corresponding fixed permanent magnet assembly 3-1 is changed to improve the stability of the quasi-zero stiffness vibration isolator. According to the weight distribution of the vibration-isolated equipment, the air gaps between the upper, middle, and middle and lower permanent magnets in the three symmetrically adjustable permanent magnet stabilization knots are adjusted respectively to achieve the purpose of adjusting the permanent magnetic repulsion, so as to achieve the functions of stable installation of the vibration-isolated equipment and prevent overturning. The symmetrical permanent magnet stabilization structure 3 and the self-adjusting spring pull rod negative stiffness structure 2 are arranged in an alternating spacing manner on the periphery, so that the stability force and the negative stiffness force are not coupled with each other, and the coupling between themselves is minimized. The symmetrical permanent magnet stabilization structure 3, while achieving the stability of the vibration-isolated equipment, can also implement real-time dynamic compensation of the stiffness of the quasi-zero stiffness vibration isolator jointly realized by the airbag positive stiffness structure 1 and the self-adjusting spring pull rod negative stiffness structure 2 within a certain vibration amplitude, thereby ensuring the continuous quasi-zero stiffness characteristics of the vibration isolator.

[0051] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0052] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. However, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A self-adjusting quasi-zero stiffness vibration isolator, characterized in that: It includes an airbag positive stiffness structure, a spring pull rod negative stiffness structure and a symmetrical permanent magnet stabilization structure; The spring pull rod negative stiffness structure and the symmetrical permanent magnet stabilization structure are alternately arranged along the circumferential direction of the airbag positive stiffness structure; the spring pull rod negative stiffness structure is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure, and the symmetrical permanent magnet stabilization structure is correspondingly connected to the top, middle and bottom of the airbag positive stiffness structure; The airbag positive stiffness structure includes an upper cover plate, a lower cover plate, and an airbag group formed by at least two airbags connected in series up and down; the upper end of the upper airbag is connected to the upper cover plate, and the lower end of the lower airbag is connected to the lower cover plate; the two adjacent airbags are connected by a middle connecting plate; the airbags are provided with an inflation port; The spring pull rod negative stiffness structure includes two parallel arranged negative stiffness components, and the two negative stiffness components are located on the outside of the same side of the middle connecting plate; the negative stiffness component includes a cross, a mechanical linear spring, an upper pull rod and a lower pull rod; the cross is arranged on the outside of the middle connecting plate, the inner end of the horizontal section of the cross is connected to one end of the mechanical linear spring, and the other end of the mechanical linear spring is connected to the middle connecting plate; the upper end of the vertical section of the cross is hinged to the lower end of the upper pull rod, and the upper end of the upper pull rod is hinged to the upper cover plate; the lower end of the vertical section of the cross is hinged to the upper end of the lower pull rod, and the lower end of the lower pull rod is hinged to the lower cover plate; The symmetrical permanent magnet stabilization structure includes a fixed permanent magnet assembly, a lifting permanent magnet assembly and a driving assembly; the fixed permanent magnet assembly has two groups, which are respectively installed on the outer sides of the upper cover plate and the lower cover plate through connecting seats; the lifting permanent magnet assembly has two groups, which are respectively arranged at the upper and lower parts of the driving assembly; the lifting permanent magnet assembly located at the upper part is arranged in pairs with the fixed permanent magnet assembly on the outer side of the upper cover plate; the lifting permanent magnet assembly located at the lower part is arranged in pairs with the fixed permanent magnet assembly on the outer side of the lower cover plate; the driving assembly is fixed on the middle connecting plate, and the driving ends of the driving assembly are respectively connected to the two lifting permanent magnet assemblies; the driving assembly drives the two lifting permanent magnet assemblies to move up and down, changing the air gap between them and the corresponding fixed permanent magnet assemblies; The permanent magnet of the fixed permanent magnet assembly and the permanent magnet of the corresponding lifting permanent magnet assembly are vertically opposite and have the same polarity.

2. The self-adjusting quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The upper cover plate, lower cover plate and middle connecting plate are all hexagonal plates, and the edges of each plate correspond to each other up and down; two connecting bolt plates for connecting to the negative stiffness structure of the spring pull rod are respectively provided on the three spaced edges of the upper cover plate and the lower cover plate, and the connecting bolt plates on the corresponding edges of the upper cover plate and the lower cover plate also correspond to each other up and down; the middle connecting plate is provided with a connecting ear plate for connecting to the negative stiffness structure of the spring pull rod.

3. The self-adjusting quasi-zero stiffness vibration isolator according to claim 2, characterized in that: In each negative stiffness component, there are two upper pull rods, which are arranged in parallel. The lower ends of the two upper pull rods are connected to the upper end of the vertical section of the cross through the same pin, and the upper ends of the two upper pull rods are connected to the connecting bolt plate of the upper cover through the same pin; there are two lower pull rods, which are arranged in parallel. The upper ends of the two lower pull rods are connected to the lower end of the vertical section of the cross through the same pin, and the lower ends of the two lower pull rods are connected to the connecting bolt plate of the lower cover through the same pin.

4. The self-adjusting quasi-zero stiffness vibration isolator according to claim 1, wherein: The fixed permanent magnet assembly and the lifting permanent magnet assembly have the same structure, both including a mounting frame and a permanent magnet arranged in the mounting frame; the mounting frame of the fixed permanent magnet assembly is connected to the upper cover plate or the lower cover plate, and the mounting frame of the lifting permanent magnet assembly is connected to the driving assembly.

5. The self-adjusting quasi-zero stiffness vibration isolator according to claim 4, characterized in that: The driving assembly includes a base and a driving mechanism provided at the upper and lower parts of the base; the base is connected to the middle connecting plate; the driving mechanism includes a horizontal threaded rod, two moving blocks and two lifting rods; the threaded rod is rotatably mounted on the base, and the two moving blocks are threadedly connected to the threaded rod and are respectively located at the two ends of the threaded rod; one end of the two lifting rods is hinged to the two moving blocks respectively, and the other end of the two lifting rods is hinged to the mounting frame of the lifting permanent magnet assembly.

6. The self-adjusting quasi-zero stiffness vibration isolator according to claim 5, characterized in that: The mounting frame of the lifting permanent magnet assembly is provided with an ear plate, which is connected to the end of the lifting rod through a pin shaft; the end of the threaded rod is provided with a knob for driving the threaded rod to rotate.

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