Self-adaptive bearing weight quasi-zero stiffness vibration isolator and control method thereof

Abstract

The invention discloses a self-adaptive bearing weight quasi-zero stiffness vibration isolator and a control method thereof, and relates to the technical field of vibration isolation equipment. The device comprises a base, the tops of the two sides of the inner wall of the base are fixedly connected with horizontal guide rails, the horizontal guide rails are slidably connected with horizontal sliding blocks, the horizontal sliding blocks are fixedly provided with magnetic torsion negative stiffness mechanisms, the output ends of the magnetic torsion negative stiffness mechanisms are fixedly connected with connecting rods, and the other ends of the connecting rods are rotationally connected with a supporting table; the supporting table is located in the center of the base. The quasi-zero stiffness is formed by the negative stiffness of the magnetic torsion negative stiffness mechanism and the positive stiffness of the vertical spring so as to achieve low-frequency vibration isolation of equipment, quasi-zero stiffness matching of the vibration isolator to equipment with different weights can be achieved by adjusting the working length of the vertical spring, the optimal low-frequency vibration isolation effect is achieved, and the low-frequency vibration isolation efficiency is improved. And the non-linear stiffness of the quasi-zero stiffness vibration isolator for equipment with different weights is completely consistent, that is, the vibration isolator has the same dynamic characteristics under the equipment with different weights.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vibration isolation equipment, in particular to a self-adaptive load weight quasi-zero stiffness vibration isolator and a control method thereof. BACKGROUND

[0002] In the field of vibration isolation equipment today, linear vibration isolators are difficult to meet the demand for good low-frequency vibration isolation due to their own limitations, so quasi-zero stiffness nonlinear vibration isolators with high static and low dynamic stiffness characteristics have emerged and been widely studied. However, it is found in practical applications that the nonlinear quasi-zero stiffness vibration isolator is extremely sensitive to the load weight, and once there is a slight error between the actual weight and the design target weight, the system balance position will deviate seriously from the quasi-zero stiffness point, thereby greatly weakening the low-frequency vibration isolation effect, which greatly limits the application range of the quasi-zero stiffness vibration isolator in practical engineering.

[0003] To solve this problem and improve the adaptability to the load weight, some studies have begun to involve the design of active control quasi-zero stiffness vibration isolators based on electromagnetic mechanisms. Although such vibration isolators can adapt to different load weights, the electromagnetic quasi-zero stiffness structure continuously consumes a large amount of energy during operation, which again limits its engineering application. Therefore, the present application proposes a self-adaptive load weight quasi-zero stiffness vibration isolator and a control method thereof. SUMMARY

[0004] The purpose of the present application is to provide a self-adaptive load weight quasi-zero stiffness vibration isolator and a control method thereof to solve the problems raised in the background.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solution: a self-adaptive load weight quasi-zero stiffness vibration isolator, comprising a base, the inner wall of the base is fixedly connected with horizontal guide rails at the top of both sides, horizontal sliding blocks are slidingly connected to the horizontal guide rails, a magnetic torsional negative stiffness mechanism is fixedly installed on the horizontal sliding blocks, a connecting rod is fixedly connected to the output end of the magnetic torsional negative stiffness mechanism, and a support table is rotatably connected to the other end of the connecting rod, and the support table is located at the center of the base.

[0006] A vertical spring is connected to the bottom center position of the support table, a sliding seat is coaxially installed at the bottom end of the vertical spring, a lead screw is coaxially and threadedly connected to the inside of the sliding seat, and the lead screw is rotatably installed on the base.

[0007] In the initial state, the support table is higher than the horizontal guide rails, the connecting rod has an initial included angle with the horizontal guide rails, and the vertical spring has no pre-compression or pre-stretching.

[0008] In the working state, the support table is flush with the horizontal guide rails, the included angle between the connecting rod and the horizontal guide rails is zero, and thus the vertical dynamic stiffness of the vibration isolator system is zero.

[0009] Further, the horizontal guide rails are fixed on the base by bolts, and the number of the horizontal guide rails is two, and the two horizontal guide rails are symmetrically arranged along the center line of the base.

[0010] Further, the magnetic torsional negative stiffness mechanism comprises a shell fixed on the horizontal slider, and a rotating shaft is rotatably arranged in the shell through a bearing.

[0011] A plurality of outer magnets are circumferentially and equidistantly arranged on the inner wall of the shell, and the magnetic poles of the plurality of outer magnets are alternately arranged, and a plurality of inner magnets are circumferentially and equidistantly arranged on the outer side wall of the rotating shaft, and the magnetic poles of the plurality of inner magnets are alternately arranged.

[0012] Further, the number of the outer magnets and the inner magnets is even, and the outer magnets and the inner magnets are all arranged as tile-shaped magnets, and in the initial state, the magnetic poles of the corresponding outer magnets and inner magnets attract each other and keep a stable state.

[0013] Further, the number of the connecting rods and the magnetic torsional negative stiffness mechanisms is four, and the connecting rods are fixedly connected with the rotating shafts of the magnetic torsional negative stiffness mechanisms through bolts.

[0014] Further, the shape of the support table is rectangular, the four connecting rods and the magnetic torsional negative stiffness mechanisms are divided into two groups, two connecting rods and a magnetic torsional negative stiffness mechanism constitute one group, the two groups of connecting rods and magnetic torsional negative stiffness mechanisms are symmetrically arranged along the transverse center line of the base, and the connecting rods and the magnetic torsional negative stiffness mechanisms in the same group are symmetrically arranged along the vertical center line of the base.

[0015] Further, the connecting rods are rotatably connected between the rotating pins and the support table.

[0016] Further, the bottom end of the lead screw is fixedly installed with a motor, the motor is fixed on the base, the top of the motor is installed with a vertical guide rail bracket through bolts, the vertical guide rail bracket is fixedly installed with a vertical guide rail, and the sliding seat is slidably connected on the vertical guide rail for constraining the rotation of the sliding seat.

[0017] Further, the base is fixedly connected with a displacement sensor for measuring the displacement of the support table.

[0018] According to the second aspect of the present application, the present application provides a control method of an adaptive load weight quasi-zero stiffness vibration isolator, comprising the following steps:

[0019] S1. In the initial state, the connecting rods and the horizontal guide rails have an initial included angle, and the vertical springs have no pre-compression or pre-tension, and the distance between the initial state and the working state position of the support table is defined as the target displacement H0:

[0020] H0=L sinθ0

[0021] Where L is the length of the connecting rod;

[0022] S2. Place the vibration isolation device on the support platform. If the weight m of the vibration isolation device is the same as the initial design target weight m0, that is, m = m0, then under the action of the magnetic torsional negative stiffness mechanism and the vertical spring, the actual displacement Y of the support platform is measured by the displacement sensor. st Equal to the target displacement H0, that is:

[0023] Y st =H0

[0024] At this point, the isolator as a whole does not need to be adjusted;

[0025] S3. If the weight of the vibration isolation equipment is greater than the initial design target weight, that is, m>m0, then:

[0026] Y st >H0

[0027] At this time, the motor is started to drive the screw to rotate in the forward direction, and the threaded engagement relationship between the screw and the sliding seat is used to move the sliding seat upward, thereby reducing the working length of the vertical spring and increasing the restoring force of the vertical spring. At this time, the support platform will move upward under the elastic force of the vertical spring until Y st =H0, the adjustment is completed. At this time, the ideal load-bearing weight of the system will be consistent with the weight of the vibration isolation equipment, and the static equilibrium position will coincide with the quasi-zero stiffness position, thus achieving optimal vibration isolation;

[0028] S4. If the weight of the vibration isolation equipment is less than the initial design target weight of the vibration isolator, that is, m <m0,则有:

[0029] Y st <H0

[0030] At this time, the static equilibrium position of the support table is above the horizontal position. The motor is started to drive the screw to rotate in the opposite direction, and the threaded engagement relationship between the screw and the sliding seat is used to move the sliding seat downward, thereby extending the working length of the vertical spring, that is, reducing the restoring force of the vertical spring, and the support table moves downward until Y st =H0, the adjustment is completed. At this time, the ideal load-bearing weight of the system will be consistent with the weight of the equipment, and the static equilibrium position will coincide with the quasi-zero stiffness position, thus achieving optimal vibration isolation.

[0031] The present invention has at least the following beneficial effects:

[0032] 1. The present invention utilizes the negative stiffness of the magnetic torsion negative stiffness mechanism and the positive stiffness of the vertical spring to form a quasi-zero stiffness to achieve low-frequency vibration isolation of the equipment. The working length of the vertical spring can easily achieve quasi-zero stiffness matching of the vibration isolator for equipment of different weights, thereby obtaining the optimal low-frequency vibration isolation effect. The control method is extremely simple. Furthermore, the nonlinear stiffness of the quasi-zero stiffness vibration isolator is completely consistent for equipment of different weights, that is, the vibration isolator has the same dynamic characteristics for equipment of different weights.

[0033] 2. The present invention is essentially a passive vibration isolator that uses permanent magnets to achieve matching for different load masses. Compared with electromagnetic active control quasi-zero stiffness vibration isolators that require continuous energy input, the vibration isolator does not require continuous external energy input when working. It only needs to control the motor to adjust the working length of the vertical spring after the device is placed to achieve load weight adaptation.

[0034] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a front view of the overall structure of the present invention;

[0036] Figure 2 A top view of the overall structure of the present invention;

[0037] Figure 3 This is a schematic diagram of the sliding seat rotation constraint structure of the present invention;

[0038] Figure 4 Schematic diagram of the three-dimensional magnetic torsional negative stiffness mechanism of the present invention;

[0039] Figure 5 Schematic cross-sectional view of the magnetic torsional negative stiffness mechanism of the present invention;

[0040] Figure 6 Schematic diagram of the magnet arrangement of the magnetic torsional negative stiffness mechanism of the present invention, wherein the arrow indicates the magnetization direction;

[0041] Figure 7 is a relationship diagram between vertical load and vertical displacement of the vibration isolator of the present invention;

[0042] Figure 8 This is a diagram showing the relationship between the torque of the magnetic torsional negative stiffness mechanism of the present invention and the angle between the connecting rod and the horizontal guide rail;

[0043] Figure 9 Schematic diagram of the control method of the present invention.

[0044] Reference numerals:

[0045] 1. Support platform; 2. Magnetic torsional negative stiffness mechanism; 3. Connecting rod; 4. Rotating pin; 5. Horizontal slider; 6. Horizontal guide rail; 7. Fastening screw; 8. Vertical spring; 9. Displacement sensor; 10. Motor; 11. Screw; 12. Sliding seat; 13. Base; 14. Vertical guide rail; 15. Vertical guide rail bracket; 16. Rotating shaft; 17. Housing; 18. External magnet; 19. Internal magnet; 20. Bearing. DETAILED DESCRIPTION

[0046] The following will be combined with the accompanying drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the embodiments described are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present disclosure.

[0047] Example 1:

[0048] See also Figures 1-9 The present invention provides a technical solution: an adaptive load-bearing quasi-zero stiffness vibration isolator, comprising a base 13, horizontal guide rails 6 fixedly connected to the top of both sides of the inner wall of the base 13, a horizontal slider 5 slidably connected to the horizontal guide rails 6, a magnetic torsional negative stiffness mechanism 2 fixedly mounted on the horizontal slider 5, an output end of the magnetic torsional negative stiffness mechanism 2 fixedly connected to a connecting rod 3, the other end of the connecting rod 3 rotatably connected to a support platform 1, and the support platform 1 is located at the center of the base 13;

[0049] A vertical spring 8 is connected to the center of the bottom of the support platform 1. A sliding seat 12 is coaxially mounted on the bottom end of the vertical spring 8. A screw rod 11 is coaxially threadedly connected to the inside of the sliding seat 12. The screw rod 11 is mounted on the motor 10.

[0050] In the initial state, the support platform 1 is higher than the horizontal guide rail 6, the connecting rod 3 and the horizontal guide rail 6 have an initial angle, and the vertical spring 8 is not pre-compressed or pre-stretched;

[0051] In the working state, the support platform 1 is flush with the horizontal guide rail 6, and the angle between the connecting rod 3 and the horizontal guide rail 6 is zero, thereby achieving zero vertical dynamic stiffness of the vibration isolator system.

[0052] Regarding the technical solution of this embodiment, Figure 3 As shown, a vertical guide rail bracket 15 is installed on the top of the motor by bolts, a vertical guide rail 14 is fixedly installed on the vertical guide rail bracket 15, and a sliding seat 12 is slidably connected to the vertical guide rail 14 to constrain the rotation of the sliding seat.

[0053] According to the technical solution of this embodiment, the horizontal guide rail 6 is fixed to the base 13 by bolts. There are two horizontal guide rails 6, and the two horizontal guide rails 6 are arranged in a mirror-symmetrical manner along the center line of the base 13. The mirror-symmetrical arrangement enables the horizontal slider 5 to be evenly stressed during the sliding process, reducing the offset or shaking caused by uneven force, thereby improving the stability of the entire vibration isolation system. The symmetrical arrangement of the two horizontal guide rails 6 forms an overall rigid frame, which enhances the structural stiffness of the entire base 13, so that the base 13 can maintain better integrity when subjected to external impact or vibration, thereby improving the anti-interference ability of the vibration isolator.

[0054] Regarding the technical solution of this embodiment, Figure 4 and Figure 5 As shown, the magnetic torsional negative stiffness mechanism 2 includes a housing 17 fixed on the horizontal slider 5, and a rotating shaft 16 is rotatably mounted inside the housing 17 through a bearing 20, and the rotating shaft 16 and the housing 17 are coaxially arranged;

[0055] Multiple outer magnets 18 are installed on the inner wall of the shell 17 at equal intervals along the circumferential direction, and the magnetic poles of the multiple outer magnets 18 are arranged alternately. Multiple inner magnets 19 are installed on the outer wall of the rotating shaft 16 at equal intervals along the circumferential direction, and the magnetic poles of the multiple inner magnets 19 are arranged alternately.

[0056] Specifically, due to the stable balance of magnetic force, the entire system is in a stable state in the initial state, which is convenient for accurate measurement and control of parameters such as displacement. In the subsequent adaptive weight adjustment process, when the weight of the equipment changes and the balance position of the system needs to be adjusted, this stable magnetic foundation can make the adjustment process smoother. For example, when the motor 10 drives the screw 11 to rotate and changes the working length of the vertical spring 8, the magnetic torsional negative stiffness mechanism 2 can smoothly cooperate with this adjustment under the action of the stable magnetic force, so that the support platform 1 can smoothly move to the new balance position and maintain the quasi-zero stiffness characteristic. At the same time, the outer magnet 18 and the inner magnet 19 are respectively installed on the shell 17 and the rotating shaft 16, and are arranged at equal intervals along the circumference. This layout can make full use of the circumferential space of the shell 17 and the rotating shaft 16, improving space utilization. The design of the tile-shaped magnet also allows the magnet to better fit the shape of the shell 17 and the rotating shaft 16, further optimizing the spatial structure, so that the magnetic torsional negative stiffness mechanism 2 can generate a large magnetic torsional torque in a limited space, which is conducive to the compact design of the vibration isolator as a whole.

[0057] Furthermore, if Figure 6As shown, the number of outer magnets 18 and inner magnets 19 is set to be even, and the outer magnets 18 and inner magnets 19 are set to be tile-shaped magnets. In the initial state, the magnetic poles of the outer magnets 18 and inner magnets 19 corresponding to each other attract each other and remain in a stable state. The number of outer magnets 18 and inner magnets 19 is even, and the magnetic poles are arranged alternately. This symmetrical arrangement can make the magnetic force evenly distributed around the rotating shaft 16. In the initial state, the magnetic poles of the outer magnets 18 and inner magnets 19 corresponding to each other attract each other and remain in a stable state. This is like applying a stable constraint force to the rotating shaft 16, so that the rotating shaft 16 can stably maintain the initial position when not disturbed by external forces. During the operation of the vibration isolator, even if disturbed by a certain degree of vibration, the balance of this magnetic force can help the rotating shaft 16 quickly recover to a stable state, enhancing the stability and reliability of the entire magnetic torsional negative stiffness mechanism 2.

[0058] According to the technical scheme of the embodiment, the number of connecting rods 3 and magnetic torsional negative stiffness mechanisms 2 is four, and the connecting rods 3 are fixedly connected with the rotating shafts 16 of the magnetic torsional negative stiffness mechanisms 2 through bolts. The four connecting rods 3 and magnetic torsional negative stiffness mechanisms 2 are symmetrically distributed, which can make the support table 1 bear forces more evenly in the horizontal and vertical directions, reduce tilting or shaking caused by uneven force, and thus improve the stability of the entire vibration isolation system. During the operation of the vibration isolator, even if disturbed by external forces, it can maintain a good balance state.

[0059] Further, the support table 1 is rectangular in shape, and the four connecting rods 3 and magnetic torsional negative stiffness mechanisms 2 are divided into two groups, two by two. The two groups of connecting rods 3 and magnetic torsional negative stiffness mechanisms 2 are mirror-symmetrically arranged along the horizontal center line of the base 13, and the connecting rods 3 and magnetic torsional negative stiffness mechanisms 2 in the same group are mirror-symmetrically arranged along the vertical center line of the base 13.

[0060] According to the technical scheme of the embodiment, the connecting rod 3 is rotatably connected between the rotating pin 4 and the support table 1, and the connecting rod 3 is fixedly connected with the rotating shaft 14 through the fastening screw 7.

[0061] According to the technical scheme of the embodiment, the bottom end of the lead screw 11 is fixedly installed with a motor 10, and the motor 10 is fixed on the base 13. The motor 10 is powered by an external power source.

[0062] According to the technical scheme of the embodiment, the base 13 is fixedly connected with a displacement sensor 9 for measuring the displacement of the support table 1.

[0063] The working principle of the displacement sensor 9 is to convert the mechanical displacement of an object into a measurable electrical signal, primarily based on physical effects such as resistance, inductance, capacitance, magnetostriction, optics, or ultrasound. Depending on the type, its specific principles include potentiometer-type resistance changes, changes in inductive coupling, and adjustment of the spacing between capacitor plates, ultimately outputting an electrical signal proportional to the displacement. For the technical solution of this embodiment, the displacement sensor 9 model can be set to SCHAEVITZ TR9420A displacement sensor 9. It should be noted that this embodiment does not make specific limitations here, and the type of displacement sensor 9 can be selected based on actual conditions to meet the needs of displacement detection of the support platform 1.

[0064] Next, the technical solution of the present invention is further described with reference to specific embodiments:

[0065] like Figure 8 As shown, the restoring force and displacement curve of the quasi-zero stiffness vibration isolator of this embodiment when the number of magnetic pole pairs p = 6 (6 external magnets and 6 internal magnets) and the initial angle θ0 = 60°;

[0066] The angle between the isolator connecting rod 3 and the horizontal guide rail 6 is defined as θ, and when the connecting rod 3 is above the horizontal guide rail, θ<0; the position when θ=0 is defined as the coordinate origin (the dimensionless displacement is 0), and the displacement when θ>0 is positive;

[0067] When θ0 = 2π / p, the quasi-zero stiffness point of the isolator is exactly at the origin of the coordinate system. Therefore, the selection of the initial angle of the isolator and the number of magnetic poles must meet the above requirements.

[0068] When the equipment weight m is the same as the initial design weight m0, the vibration isolator does not need to be adjusted. Under the action of gravity, the static equilibrium position will be at a quasi-zero stiffness point, thus achieving optimal low-frequency vibration isolation.

[0069] When the equipment weight m is different from the initial design weight m0, the static equilibrium position of the system will deviate from the quasi-zero stiffness point, seriously reducing the vibration isolation effect. At this time, it is necessary to adjust the pre-tensioning / compression state of the vertical spring 8 of the vibration isolator so that the load-bearing weight of the vibration isolator at the quasi-zero stiffness point is the same as the equipment weight, thereby achieving the effect of load-bearing weight adaptation.

[0070] For different equipment weights, the required pre-tension / compression amount of the vertical spring 8 is as follows: Figure 7 As shown, when the spring is pre-compressed, the support platform 1 is subjected to an upward force, and the initial installation angle of the vibration isolator increases accordingly. At this time, the magnetic torsional negative stiffness mechanism 2 provides a negative torque (the torque is defined as a negative torque when it generates a downward force on the support platform 1 through the connecting rod 3, and a positive torque when it generates an upward force, as shown in FIG. Figure 7As shown), the upward force generated by the vertical spring 8 on the support platform 1 can be balanced, so that the support platform 1 is in a stable state. At this time, the bearing device is placed on the support platform 1. When it reaches the horizontal position (the angle θ between the connecting rod and the guide rail is defined as 0), the magnetic torsional negative stiffness mechanism 2 does not provide torque, and the bearing weight of the vibration isolator is completely provided by the vertical spring 8; compared with the state without pre-compression, the force provided by the vertical spring 8 in the horizontal position in the pre-compression state is greater, so the bearing weight of the vibration isolator increases, and the greater the weight of the equipment m is compared to the initial design weight m0, the greater the pre-compression amount required for the vertical spring 8. Similarly, Figure 7 and Figure 8 As shown, pre-stretching the vertical spring 8 can reduce the load-bearing weight of the vibration isolator. When pre-compressed, the working length of the vertical spring 8 decreases (the total compression amount increases); when pre-stretched, the working length of the vertical spring 8 increases (the total compression amount decreases). Therefore, the load-bearing weight of the vibration isolator can be adjusted by controlling the working length of the vertical spring 8.

[0071] In summary, the magnetic torsional negative stiffness mechanism 2 of the present invention can provide torsional negative stiffness, provide vertical negative stiffness for the vibration isolator under the action of the connecting rod 3, and provide linear positive stiffness by the vertical spring 8. The two are connected in parallel to form a quasi-zero stiffness vibration isolator. In the initial state of the vibration isolator, there is an initial angle between the connecting rod 3 and the horizontal guide rail 6, and the vertical spring 8 is not pre-compressed or pre-stretched. During operation, the vibration-isolating device is placed above the support plate and moves downward under the action of gravity. If the weight of the device is consistent with the initial design target weight of the vibration isolator, the quasi-zero stiffness vibration isolator reaches an equilibrium position, and the vertical dynamic stiffness of the system is basically zero. That is, high static and low dynamic stiffness characteristics are achieved, which can effectively isolate the low-frequency vibration from the base 13. Therefore, the distance from the initial displacement of the support plate to the position where the angle between the connecting rod 3 and the horizontal guide rail 6 is zero is the target displacement; when the weight of the equipment is not equal to the initial design target weight of the vibration isolator, the displacement of the system when it is in the static equilibrium position seriously deviates from the target displacement, deteriorating the low-frequency vibration isolation performance. At this time, the displacement of the support plate is measured by the displacement sensor 9, and the adjustment motor 10 controls the up and down movement of the screw rod 11 slider to adjust the working length of the vertical spring 8 so that the static equilibrium displacement is consistent with the target displacement, thereby obtaining the optimal low-frequency vibration isolation effect.

[0072] Example 2:

[0073] like Figure 9 As shown, according to a second aspect of the present invention, the present invention provides a control method for an adaptive load-bearing quasi-zero stiffness vibration isolator, comprising the following steps:

[0074] S1. In the initial state, there is an initial angle between the connecting rod 3 and the horizontal guide rail 6, and the vertical spring 8 is not pre-compressed or pre-stretched. The distance between the initial state and the working state position of the support platform 1 is defined as the target displacement H0:

[0075] H0=L sinθ0

[0076] Where, L is the length of connecting rod 3;

[0077] S2. Place the vibration isolation device on the support platform 1. If the weight m of the vibration isolation device is the same as the initial design target weight m0, that is, m=m0, then under the action of the magnetic torsional negative stiffness mechanism 2 and the vertical spring 8, the actual displacement Y of the support platform 1 is measured by the displacement sensor 9. st Equal to the target displacement H0, that is:

[0078] Y st =H0

[0079] At this point, the vibration isolator as a whole does not need to be adjusted;

[0080] S3. If the weight of the vibration isolation equipment is greater than the initial design target weight, that is, m>m0, then:

[0081] Y st >H0

[0082] At this time, the starting motor 10 drives the screw rod 11 to rotate forward, and the threaded engagement relationship between the screw rod 11 and the sliding seat 12 is used to move the sliding seat 12 upward, thereby reducing the working length of the vertical spring 8 and increasing the restoring force of the vertical spring 8. At this time, the support platform 1 will move upward under the elastic force of the vertical spring 8 until Y st =H0, the adjustment is completed. At this time, the ideal load-bearing weight of the system will be consistent with the weight of the vibration isolation equipment, and the static equilibrium position will coincide with the quasi-zero stiffness position, thus achieving optimal vibration isolation;

[0083] S4. If the weight of the vibration isolation equipment is less than the initial design target weight of the vibration isolator, that is, m <m0,则有:

[0084] Y st <H0

[0085] At this time, the static equilibrium position of the support platform 1 is above the horizontal position, and the starting motor 10 drives the screw rod 11 to rotate in the opposite direction, and the threaded engagement relationship between the screw rod 11 and the sliding seat 12 is used to move the sliding seat 12 downward, thereby extending the working length of the vertical spring 8, that is, reducing the restoring force of the vertical spring 8, and the support platform 1 moves downward until Y st =H0, the adjustment is completed. At this time, the ideal load-bearing weight of the system will be consistent with the weight of the equipment, and the static equilibrium position will coincide with the quasi-zero stiffness position, thus achieving optimal vibration isolation.

[0086] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0087] For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. When an element is referred to as being "assembled on", "installed on", "fixed on" or "set on" another element, it can be directly on the other element or there can be a central element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be a central element at the same time. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0088] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

[0089] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Claims

1. An adaptive load-bearing quasi-zero stiffness vibration isolator, comprising a base (13), characterized in that: Horizontal guide rails (6) are fixedly connected to the top of both sides of the inner wall of the base (13); a horizontal slider (5) is slidably connected to the horizontal guide rails (6); a magnetic torsion negative stiffness mechanism (2) is fixedly installed on the horizontal slider (5); an output end of the magnetic torsion negative stiffness mechanism (2) is fixedly connected to a connecting rod (3); the other end of the connecting rod (3) is rotatably connected to a support platform (1); and the support platform (1) is located at the center of the base (13); A vertical spring (8) is connected to the center of the bottom of the support platform (1), a sliding seat (12) is coaxially mounted on the bottom end of the vertical spring (8), a screw rod (11) is coaxially threadedly connected to the inside of the sliding seat (12), and the screw rod (11) is rotatably mounted on the base (13); In the initial state, the support platform (1) is higher than the horizontal guide rail (6), the connecting rod (3) and the horizontal guide rail (6) have an initial angle, and the vertical spring (8) is not pre-compressed or pre-stretched; In the working state, the support platform (1) is flush with the horizontal guide rail (6), and the angle between the connecting rod (3) and the horizontal guide rail (6) is zero, thereby achieving zero vertical dynamic stiffness of the vibration isolator system.

2. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 1, characterized in that: The horizontal guide rail (6) is fixed to the base (13) by bolts. There are two horizontal guide rails (6), and the two horizontal guide rails (6) are arranged in a mirror-symmetrical manner along the center line of the base (13).

3. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 2, characterized in that: The magnetic torsional negative stiffness mechanism (2) comprises a housing (17) fixed on a horizontal slider (5), a rotating shaft (16) being rotatably mounted inside the housing (17) via a bearing (20), and the rotating shaft (16) and the housing (17) being coaxially arranged. A plurality of external magnets (18) are mounted on the inner wall of the housing (17) at equal intervals along the circumferential direction, and the magnetic poles of the plurality of external magnets (18) are arranged alternately. A plurality of internal magnets (19) are mounted on the outer wall of the rotating shaft (16) at equal intervals along the circumferential direction, and the magnetic poles of the plurality of internal magnets (19) are arranged alternately.

4. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 3, characterized in that: The number of the outer magnets (18) and the inner magnets (19) is set to an even number, and the outer magnets (18) and the inner magnets (19) are both set to tile-shaped magnets. In the initial state, the magnetic poles of the outer magnets (18) and the inner magnets (19) corresponding to each other attract each other and maintain a stable state.

5. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 4, characterized in that: The number of the connecting rods (3) and the number of the magnetic torsion negative stiffness mechanisms (2) are both four, and the connecting rods (3) are fixedly connected to the rotating shaft (16) of the magnetic torsion negative stiffness mechanism (2) via bolts.

6. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 5, characterized in that: The support platform (1) is configured to be rectangular in shape, and the four connecting rods (3) and the magnetic torsion negative stiffness mechanism (2) are grouped in pairs, for a total of two groups. The two groups of connecting rods (3) and the magnetic torsion negative stiffness mechanism (2) are arranged in a mirror-symmetrical manner along the transverse center line of the base (13), and the connecting rods (3) and the magnetic torsion negative stiffness mechanism (2) in the same group are arranged in a mirror-symmetrical manner along the vertical center line of the base (13).

7. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 5, characterized in that: The connecting rod (3) is rotatably connected to the support platform (1) via a rotating pin (4).

8. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 7, characterized in that: The bottom end of the screw rod (11) is fixedly installed with a motor (10), the motor (10) is fixed on the base (13), the top of the motor is installed with a vertical guide rail bracket (15) through bolts, and a vertical guide rail (14) is fixedly installed on the vertical guide rail bracket (15). The sliding seat (12) is slidably connected to the vertical guide rail (14) to restrict the rotation of the sliding seat.

9. The adaptive load-bearing quasi-zero stiffness vibration isolator according to claim 8, characterized in that: A displacement sensor (9) is fixedly connected to the base (13) to measure the displacement of the support table (1).

10. A control method for an adaptive load-bearing quasi-zero stiffness vibration isolator, characterized in that: It includes the following steps: S1. In the initial state, there is an initial angle between the connecting rod (3) and the horizontal guide rail (6), and the vertical spring (8) has no pre-compression or pre-tension. Define the distance between the support table (1) in the initial state and the working state position as the target displacement H0: H0 = Lsinθ0 In the formula, L is the length of the connecting rod (3); S2. Place the vibration isolation device on the support platform (1). If the weight m of the vibration isolation device is the same as the initial design target weight m0, that is, m=m0, then under the action of the magnetic torsional negative stiffness mechanism (2) and the vertical spring (8), the actual displacement Y of the support platform (1) is measured by the displacement sensor (9). st Equal to the target displacement H0, that is: Y st =H0 At this time, the overall vibration isolator does not need to be adjusted; S3. If the weight of the vibration isolation device is greater than the initial design target weight, that is, m>m0, then there is: Y st >H0 At this time, the motor (10) is started to drive the screw rod (11) to rotate in the forward direction, and the threaded engagement relationship between the screw rod (11) and the sliding seat (12) is used to move the sliding seat (12) upward, thereby reducing the working length of the vertical spring (8) and increasing the restoring force of the vertical spring (8). At this time, the support platform (1) will move upward under the elastic force of the vertical spring (8) until Y st =H0, the adjustment is completed. At this time, the ideal load-bearing weight of the system will be consistent with the weight of the vibration isolation equipment, and the static equilibrium position will coincide with the quasi-zero stiffness position, thus achieving optimal vibration isolation; S4. If the weight of the vibration isolation device is less than the initial design target weight of the vibration isolator, that is, m<m0, then there is: AND st <H0 At this time, the static equilibrium position of the support platform (1) is above the horizontal position, and the starting motor (10) drives the screw rod (11) to rotate in the opposite direction, and the threaded engagement relationship between the screw rod (11) and the sliding seat (12) is used to move the sliding seat (12) downward, thereby extending the working length of the vertical spring (8), that is, reducing the restoring force of the vertical spring (8), and the support platform (1) moves downward until Y st =H0, the adjustment is completed. At this time, the ideal load-bearing weight of the system will be consistent with the weight of the equipment, and the static equilibrium position will coincide with the quasi-zero stiffness position, thus achieving optimal vibration isolation.

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