A wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, control method and platform

Abstract

This invention provides a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, control method, and platform. The device includes a loading platform, an upper cover plate, a lower cover plate, a low dynamic stiffness module, a guide rod, a high static stiffness module, and a controller. The low dynamic stiffness module is coaxially formed by a long secondary, a short primary, and the motor housing, generating a constant electromagnetic support force along the vibration isolation direction through electromagnetic coupling to counteract the load gravity. The guide rod penetrates the motor housing and connects to the upper and lower cover plates, constraining its movement along the vibration isolation direction. The high static stiffness module consists of upper and lower disc-type eddy current stators and corresponding annular magnetic plates, generating electromagnetic attraction to form boundary constraints when the motor housing deviates from the equilibrium range. The loading platform is connected to the motor housing via a support rod. This invention achieves stable quasi-zero stiffness characteristics over a wide stroke range through the segmented cooperation of the low dynamic stiffness and high static stiffness modules, and also possesses a certain stiffness adjustment capability.

Description

Technical Field

[0001] This invention relates to the field of low-frequency vibration isolation technology, and in particular to a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, control method and platform. Background Technology

[0002] With the increasing demands for precision control, service reliability, and environmental adaptability in high-end equipment fields such as aerospace and shipbuilding, efficient isolation of low-frequency vibrations has become a core engineering problem that urgently needs to be solved in the field of vibration control.

[0003] Traditional linear vibration isolation systems suffer from a contradiction between natural frequency and load-bearing capacity. To achieve low-frequency isolation, system stiffness must be reduced to lower the natural frequency, often resulting in insufficient static stiffness to meet high load-bearing requirements. To resolve this contradiction, quasi-zero stiffness (QZS) vibration isolation structures based on the principle of positive and negative stiffness matching have emerged. Existing technologies often employ passive components such as three-spring mechanisms, disc springs, cam-roller mechanisms, and buckling structures, using parallel negative stiffness mechanisms to offset positive stiffness, thereby achieving "high static, low dynamic" characteristics at specific locations. However, passive quasi-zero stiffness isolators typically only exhibit ideal performance near fixed loads and small displacements, making it difficult to adapt to complex and variable external load fluctuations.

[0004] In recent years, electromagnetic negative stiffness mechanisms have gradually become an important research direction in high-performance vibration isolation technology due to their advantages such as non-contact operation, fast response, and high adjustability. However, existing electromagnetic quasi-zero stiffness vibration isolators still have the following problems:

[0005] The effective quasi-zero stiffness range is narrow. Due to the nonlinear mechanical characteristics of positive and negative stiffness matching, the vibration isolator exhibits near-zero stiffness characteristics only within a very small stroke range (between a few millimeters and tens of millimeters). Under severe loads or large displacement excitation, it is easy to deviate from the quasi-zero stiffness range, resulting in a significant deterioration in vibration isolation performance.

[0006] Large stroke performance instability is due to the fact that its design mechanism essentially still relies on displacement-related nonlinear force cancellation, making it difficult to maintain stable low dynamic stiffness over a wide stroke range.

[0007] It lacks the ability to adapt to varying loads and struggles to balance gravity compensation throughout the entire stroke with stiffness limit protection under extreme conditions.

[0008] Therefore, the challenge lies in breaking free from the constraints of traditional parallel positive and negative stiffness mechanisms and providing a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, control method, and platform that can maintain stable quasi-zero stiffness characteristics over a wide stroke range and has segmented stiffness adjustment capabilities. Summary of the Invention

[0009] The purpose of this invention is to provide a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, control method and platform, which aims to solve the technical problems of existing quasi-zero stiffness vibration isolators having a narrow effective range, deteriorated vibration isolation performance over large strokes and insufficient adaptability to variable loads.

[0010] To achieve the above objectives, in a first aspect, the present invention provides a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, comprising a loading platform, an upper cover plate and a lower cover plate disposed opposite to each other; and further comprising:

[0011] The low dynamic stiffness module includes a long secondary, a short primary and a motor housing arranged coaxially in sequence. The short primary is floated and sleeved on the outside of the long secondary and nested inside the motor housing. When energized, the short primary is electromagnetically coupled to the long secondary to generate a constant electromagnetic support force along the vibration isolation direction.

[0012] A guide rod that can slide through the motor housing, with its two ends connected to the upper cover plate and the lower cover plate respectively;

[0013] The high static stiffness module includes a disc-shaped eddy current stator and an annular magnetic plate disposed on the upper and lower sides of the low dynamic stiffness module. The two annular magnetic plates are fixed to the upper and lower surfaces of the motor housing, respectively. The two disc-shaped eddy current stators are disposed on the inner surfaces of the upper and lower cover plates, respectively. When energized, the disc-shaped eddy current stators interact with the corresponding annular magnetic plates to generate electromagnetic attraction.

[0014] The controller is electrically connected to the low dynamic stiffness module and the high static stiffness module, respectively.

[0015] The loading platform is positioned directly above the upper cover plate and is connected to the motor housing via a support rod.

[0016] The low dynamic stiffness module provides electromagnetic support constant force to counteract the load gravity, while the high static stiffness module provides boundary constraint force when the motor housing deviates from the equilibrium range, so that the vibration isolator forms segmented quasi-zero stiffness characteristics.

[0017] As a further improvement to the above solution, the long secondary includes a cylindrical iron secondary and a cylindrical copper secondary arranged coaxially;

[0018] The cylindrical iron secondary is fixedly disposed between the upper cover plate and the lower cover plate, and the cylindrical copper secondary is attached to the outer surface of the cylindrical iron secondary.

[0019] As a further improvement to the above scheme, the short primary includes a cylindrical linear induction motor stator core and a three-phase AC winding embedded in the cylindrical linear induction motor stator core.

[0020] As a further improvement to the above solution, the short primary is sleeved outside the long secondary and fixedly connected to the motor housing so as to float synchronously with the motor housing along the vibration isolation direction.

[0021] As a further improvement to the above solution, the high static stiffness module includes an upper disc eddy current stator and a lower disc eddy current stator. The upper disc eddy current stator is disposed on the inner surface of the upper cover plate and is correspondingly disposed with an annular magnetic plate fixed on the upper surface of the motor housing.

[0022] The lower disc-type eddy current stator is disposed on the inner surface of the lower cover plate and is correspondingly disposed with the annular magnetic plate fixed to the lower surface of the motor housing.

[0023] As a further improvement to the above scheme, the upper disc eddy current stator and the lower disc eddy current stator have the same structure, each including several stator cores, each corresponding to several DC coils surrounding the stator cores, and arranged circumferentially around the cylindrical iron secondary to form a disc eddy current stator.

[0024] As a further improvement to the above solution, four guide rods are provided, and the four guide rods are evenly distributed at 90° around the central axis of the long secondary module to guide the movement of the low dynamic stiffness module.

[0025] As a further improvement to the above solution, the support rod is provided with four rods, which are evenly distributed at 90° around the central axis of the long secondary stage, and the four support rods and the four guide rods are staggered in the circumferential direction to transfer the weight of the load-bearing object to the low dynamic stiffness module so that the loading platform and the low dynamic stiffness module move together.

[0026] As a further improvement to the above solution, the controller is used to adjust the current parameters of the low dynamic stiffness module to adjust the electromagnetic support constant force output by the low dynamic stiffness module; the controller is also used to adjust the current parameters of the high static stiffness module to adjust the boundary constraint force output by the high static stiffness module.

[0027] As a further improvement to the above solution, the loading platform is equipped with a gravity sensor electrically connected to the controller for detecting load information;

[0028] The controller adjusts the current parameters of the low dynamic stiffness module based on the load information detected by the gravity sensor, so that the electromagnetic support constant force output by the low dynamic stiffness module matches the load gravity.

[0029] In a second aspect, the present invention also provides a control method for the broadband adjustable electromagnetic quasi-zero stiffness isolator described in the first aspect, comprising the following steps:

[0030] S1. Obtain the load information of the load carried by the vibration isolator, and control the low dynamic stiffness module to output the electromagnetic support constant force along the vibration isolation direction according to the load information, so that the electromagnetic support constant force matches the load gravity, so as to establish the balanced working state of the vibration isolator.

[0031] S2. Control the high static stiffness module to be in a preset working state, so that the upper high static stiffness module and the lower high static stiffness module have the ability to output boundary constraint force in their respective effective action areas.

[0032] S3. During the operation of the vibration isolator, the position of the motor housing relative to the equilibrium zone is detected. When the motor housing is within the equilibrium zone, the low dynamic stiffness module provides electromagnetic support constant force to counteract the load gravity. When the motor housing deviates from the equilibrium zone and enters the corresponding effective action zone, the high static stiffness module on the corresponding side outputs boundary constraint force, which works together with the low dynamic stiffness module to form a segmented quasi-zero stiffness vibration isolation.

[0033] As a further improvement to the above scheme, the step of controlling the output of the low dynamic stiffness module to generate the electromagnetic support constant force along the vibration isolation direction based on the load information specifically includes: the controller adjusting the current parameters of the low dynamic stiffness module to adjust the electromagnetic support constant force generated by the electromagnetic coupling between the short primary and long secondary after energization.

[0034] Preferably, the current parameters of the low dynamic stiffness module include the current amplitude and / or frequency supplied to the short primary.

[0035] As a further improvement to the above solution, the control high static stiffness module is in a preset working state, specifically including: the controller adjusts the current parameters of the disc eddy current stator so that the disc eddy current stator outputs electromagnetic attraction when the corresponding annular magnetic plate enters the effective range; the current parameters include the magnitude of the DC current flowing into the disc eddy current stator.

[0036] As a further improvement to the above scheme, when an increase in load is detected, the controller increases the current parameter of the low dynamic stiffness module to improve the electromagnetic support constant force output by the low dynamic stiffness module; when a decrease in load is detected, the controller decreases the current parameter of the low dynamic stiffness module to reduce the electromagnetic support constant force output by the low dynamic stiffness module.

[0037] As a further improvement to the above scheme, when the motor housing deviates upward from the balance range and enters the effective range of the upper disc-type eddy current stator, electromagnetic attraction is generated by the interaction between the upper disc-type eddy current stator and the corresponding annular magnetic plate; when the motor housing deviates downward from the balance range and enters the effective range of the lower disc-type eddy current stator, electromagnetic attraction is generated by the interaction between the lower disc-type eddy current stator and the corresponding annular magnetic plate.

[0038] Thirdly, the present invention also provides a wideband adjustable electromagnetic quasi-zero stiffness vibration isolation platform, including a base and a vibration isolation platform from top to bottom, and a plurality of wideband adjustable electromagnetic quasi-zero stiffness vibration isolators as described in the first aspect. The plurality of vibration isolators are disposed between the base and the vibration isolation platform, and their two ends are respectively hinged and fixed to the base and the vibration isolation platform.

[0039] Because the present invention adopts the above technical solutions, the beneficial effects of this application are as follows:

[0040] This invention provides a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, which adopts a segmented matching design of a low dynamic stiffness module and a high static stiffness module along the vibration isolation direction. Firstly, it achieves complete decoupling of the two core functions of load support and boundary constraint from a structural perspective: the low dynamic stiffness module, through electromagnetic coupling of a long secondary and a short primary, can output a stable electromagnetic constant force along the vibration isolation direction throughout the entire design stroke, completely offsetting the load gravity and providing the system with a foundation load without stiffness fluctuations; while the effective operating range of the high static stiffness module is limited to the two ends of the quasi-zero stiffness equilibrium range, and it does not intervene at all within the equilibrium range, and will not have any additional impact on the system stiffness. Based on the segmented functional matching design, the system only has a constant electromagnetic force output by the low dynamic stiffness module within the equilibrium range, without any additional stiffness interference. Therefore, the system stiffness can always remain zero within this range. At the same time, since the low dynamic stiffness module adopts a long secondary structure, its effective constant force output stroke can be flexibly designed to be hundreds or even thousands of millimeters according to actual working conditions. The corresponding quasi-zero stiffness effective working range can be extended to the same length, fundamentally solving the inherent defects of existing quasi-zero stiffness vibration isolators, such as narrow effective working range and only being able to adapt to small amplitude vibrations, and greatly expanding the applicable scenarios of low-frequency vibration isolation. Meanwhile, this invention addresses the industry pain point of balancing ultra-wide vibration isolation range with system operational stability through segmented functional decomposition: within the equilibrium range, the high static stiffness module completely deactivates, preserving the system's zero-stiffness vibration isolation characteristics and ensuring the vibration isolation effect; when the system is affected by external excitation and the displacement exceeds the equilibrium range, the high static stiffness module can quickly intervene, providing a boundary constraint force that significantly increases with displacement through the electromagnetic interaction of the disc-type eddy current stator and the annular magnetic plate, limiting further displacement and preventing system instability. This design achieves an ultra-wide quasi-zero stiffness vibration isolation range while ensuring the reliability of the system throughout its entire stroke, significantly improving the environmental adaptability of the vibration isolation device.

[0041] Secondly, the low dynamic stiffness module of this invention adopts a structure in which a long secondary, a short primary, and the motor housing are arranged coaxially in sequence. The short primary can float up and down along the long secondary and is nested entirely within the motor housing. This ensures constant force output from the electromagnetic support while facilitating a more compact axial force path. Combined with the guiding effect of the guide rod on the movement trajectory of the motor housing, the motor housing can move relatively stably along the vibration isolation direction, reducing the adverse effects of sway on vibration isolation performance. This helps maintain the stability of the device's working state under large stroke conditions and alleviates the problem of easy degradation of vibration isolation performance under large stroke conditions.

[0042] Furthermore, this invention incorporates high static stiffness modules on both the upper and lower sides of the low dynamic stiffness module, and employs correspondingly arranged disc-type eddy current stators and annular magnetic plates to form a double-boundary constraint structure. When the motor housing deviates upward or downward from the equilibrium range, the corresponding high static stiffness module generates electromagnetic attraction, limiting its displacement. This structure allows the device to maintain low dynamic stiffness within the intermediate working range, while providing additional constraints near the boundaries, thus balancing the low stiffness required for vibration isolation with the stability requirements under large displacement conditions.

[0043] Furthermore, the load-bearing platform of this invention is connected to the motor housing via support rods, enabling the load to be transferred to the main structure where both the low dynamic stiffness module and the high static stiffness module participate in the operation. This connection method, in conjunction with the aforementioned coaxial arrangement structure, facilitates a more direct load transfer path, thereby improving the system's stress coordination during load-bearing and vibration isolation processes.

[0044] Furthermore, this invention provides a controller electrically connected to both the low dynamic stiffness module and the high static stiffness module, allowing for separate adjustments to the two types of modules based on operating conditions. Specifically, the controller can adjust the operating parameters of the low dynamic stiffness module to alter the magnitude of the electromagnetic support constant force, better matching it to different loads. Simultaneously, it can adjust the operating parameters of the high static stiffness module to change the boundary constraint force. Thus, the device not only maintains its corresponding operating state under different load conditions but also provides targeted constraints based on displacement deviations, thereby improving its adaptability to variable load conditions.

[0045] Finally, this invention employs electromagnetic methods for support and constraint, which, compared to structures relying on nonlinear combinations of mechanical springs to achieve quasi-zero stiffness characteristics, reduces the degree to which mechanical contact components directly participate in the main support and boundary constraint processes. This provides flexibility in structural adjustment, parameter control, and adaptability to operating conditions, and also lays the structural foundation for achieving broadband adjustable vibration isolation. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0047] Figure 1 This is a three-dimensional schematic diagram of a broadband adjustable electromagnetic quasi-zero stiffness vibration isolator disclosed in this invention;

[0048] Figure 2 This is a three-dimensional cross-sectional schematic diagram of a broadband adjustable electromagnetic quasi-zero stiffness vibration isolator disclosed in this invention;

[0049] Figure 3 This is a cross-sectional schematic diagram of the low dynamic stiffness module disclosed in this invention;

[0050] Figure 4 This is a three-dimensional schematic diagram of the high dynamic stiffness module disclosed in this invention;

[0051] Figure 5 This invention discloses a segmented working principle diagram of a broadband adjustable electromagnetic quasi-zero stiffness vibration isolator. Figure (a) shows the structure and stroke segmentation of the vibration isolator; Figure (b) shows the electromagnetic attraction F of the lower high static stiffness module. h2 Characteristic curves; Figure (c) shows the electromagnetic force F of the low dynamic stiffness module. l Characteristic curves; Figure (d) shows the electromagnetic attraction F of the upper high static stiffness module. h1 Characteristic curves; Figure (e) is a schematic diagram of the total restoring force curve of the system, and Figure (f) is a schematic diagram of the stiffness curve of the system;

[0052] Figure 6 This is a three-dimensional schematic diagram of a broadband adjustable electromagnetic quasi-zero stiffness vibration isolation platform disclosed in this invention.

[0053] Figure label:

[0054] 01. Wideband adjustable electromagnetic quasi-zero stiffness vibration isolator; 1. Loading platform; 2. Upper cover plate; 3. Lower cover plate; 4. Low dynamic stiffness module; 41. Long secondary; 411. Cylindrical iron secondary; 412. Cylindrical copper secondary; 42. Short primary; 421. Cylindrical linear induction motor stator core; 422. Three-phase AC winding; 43. Motor housing; 5. Guide rod; 6. High static stiffness module; 61. Upper disc eddy current stator; 62. Lower disc eddy current stator; 63. Annular magnetic plate; 64. Stator core; 65. DC coil; 7. Support rod; 02. Base; 03. Vibration isolation table.

[0055] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] It should be noted that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0058] Example 1

[0059] See Figures 1-5 This invention provides a wideband adjustable electromagnetic quasi-zero stiffness vibration isolator to improve the problems of existing quasi-zero stiffness vibration isolators, such as narrow effective working range, easy degradation of vibration isolation performance under large stroke conditions, and insufficient adaptability to variable load conditions.

[0060] Specifically, the vibration isolator includes a loading platform 1, an upper cover plate 2 and a lower cover plate 3 arranged opposite each other, as well as a low dynamic stiffness module 4, a guide rod 5, a high static stiffness module 6, a controller, and a support rod 7.

[0061] The low dynamic stiffness module 4 is disposed between the upper cover plate 2 and the lower cover plate 3, and includes a long secondary 41, a short primary 42, and a motor housing 43 arranged coaxially in sequence. The long secondary 41 is fixedly disposed vertically, while the short primary 42 is flexibly fitted around the long secondary 41 and nested inside the motor housing 43. When the short primary 42 is energized, it electromagnetically couples with the long secondary 41, thereby generating a constant electromagnetic support force along the vibration isolation direction. This constant electromagnetic support force is mainly used to counteract the load gravity, enabling the vibration isolator to maintain its working state near the equilibrium range. Since the low dynamic stiffness module 4 adopts an electromagnetic support form with the long secondary 41 and the short primary 42 coaxially coupled, the support effect is mainly achieved through electromagnetic coupling. Therefore, it is beneficial to form a low dynamic stiffness in the intermediate working range, providing a basis for low-frequency vibration isolation. The low dynamic stiffness module 4 does not rely on mechanical springs to provide the main support force, thus having good flexibility in structural and parameter adjustment, and providing a basis for forming a low dynamic stiffness state in a wider working range.

[0062] The guide rod 5 can slide through the motor housing 43, and its two ends are connected to the upper cover plate 2 and the lower cover plate 3, respectively. The motor housing 43 and the guide rod 5 are in sliding engagement, so that the motor housing 43 drives the short primary 42 to move mainly in the vertical direction. As a result, the motion trajectory of the motor housing 43 is guided and constrained, which helps to reduce the adverse effects of yaw, tilt and other factors on vibration isolation performance, and is especially helpful in maintaining motion stability under large stroke conditions.

[0063] The high static stiffness module 6 includes disc-shaped eddy current stators and annular magnetic plates 63 disposed on the upper and lower sides of the low dynamic stiffness module 4. The two annular magnetic plates 63 are fixed to the upper and lower surfaces of the motor housing 43, respectively, and the two disc-shaped eddy current stators are disposed on the inner surfaces of the upper cover plate 2 and the lower cover plate 3, respectively. When energized, the disc-shaped eddy current stators interact with the corresponding annular magnetic plates 63 to generate electromagnetic attraction. When the motor housing 43 is near the equilibrium range, the high static stiffness module 6 does not bear the main supporting role; when the motor housing 43 is within the equilibrium range, the distance between the disc-shaped eddy current stators on the upper and lower sides and the corresponding annular magnetic plates 63 is large, and the high static stiffness module 6 does not participate in the main function; when the motor housing 43 deviates upward or downward from the equilibrium range and enters the effective range of the corresponding disc-shaped eddy current stator, the high static stiffness module 6 on the corresponding side begins to generate electromagnetic attraction, thereby forming a boundary constraint force. In other words, the low dynamic stiffness module 4 mainly bears the gravity counteracting effect within the equilibrium range, while the high static stiffness module 6 mainly participates in the constraint effect in the boundary region. Through this segmented action, the low stiffness support in the middle working range can be combined with the additional constraints in the boundary range, which helps to widen the effective working range of quasi-zero stiffness and improve the working stability under large displacement conditions.

[0064] The load-bearing platform 1 is positioned directly above the upper cover plate 2 and connected to the motor housing 43 via a support rod 7, enabling the load to be transferred to the vibration isolation main structure. This connection method provides a more direct load transfer path, facilitating coordinated motion between the load-bearing platform 1, the motor housing 43, and related electromagnetic components, thus ensuring stable force transmission during vibration isolation. The support rod 7 directly transfers the load to the motor housing 43, allowing both the electromagnetic support constant force generated by the low dynamic stiffness module 4 and the boundary constraint force generated by the high static stiffness module 6 to act on the load-bearing system. This configuration makes it easier to align the system's load-bearing center with the electromagnetic action center, reducing the impact of additional off-center loads on vibration isolation performance.

[0065] In this embodiment, the low dynamic stiffness module 4 and the high static stiffness module 6 are coaxially arranged in the vertical direction, and they adopt a segmented structural arrangement. Specifically, the central axes of the low dynamic stiffness module 4 and the high static stiffness module 6 coincide, and their directions of action are both vertical, so that the load-bearing support and boundary constraint effects of the vibration isolator are both carried out around the same axis of motion. This arrangement helps to reduce the adverse effects of factors such as eccentric loading and sway on the vibration isolation performance, and helps to improve the overall operational stability of the device under large stroke conditions.

[0066] See Figure 5 In the vertical direction, the movement position of the motor housing 43 is represented by the displacement coordinate y, and the working stroke is divided into y1 to y4. For details, see [link to documentation]. Figure 5 (a) Along the y-axis, the system travel is divided into three working intervals using coordinates 0, y1, y2, y3, and y4: [0, y1], [y1, y3], and [y3, y4]. Here, y2 is the static equilibrium position of the system, located within the core vibration isolation interval [y1, y3]. Therefore, the working process of the vibration isolator can be divided into the following stages:

[0067] 1. Within the stroke range [0, y4], the low dynamic stiffness module 4 is always working and generates a constant electromagnetic support force F to counteract the vibration isolation load gravity. l .

[0068] 2. Within the travel range [y1, y3], due to the large distance between the annular magnetic plates 63 on both sides and the corresponding disc-type eddy current stator, there is basically no electromagnetic attraction. Therefore, the low dynamic stiffness module 4 mainly works in this range, while the high static stiffness module 6 does not play a major role. At this time, the main output of the vibration isolator is the electromagnetic support constant force F. l It is used to counteract the gravity of the vibration isolation load, where the middle position y2 is the static equilibrium position.

[0069] 3. Within the travel range [0, y1], except for the low dynamic stiffness module 4 which continues to work, the motor housing 43 moves downward and enters the effective range of the lower disc-type eddy current stator 62. The lower high static stiffness module 6 interacts with the corresponding annular magnetic plate 63, generating a downward electromagnetic attraction force -F. h1 Therefore, the resultant electromagnetic force within this interval is F. l -F h1 .

[0070] 4. Within the travel range [y3, y4], except for the low dynamic stiffness module 4 which continues to work, the motor housing 43 moves upward and enters the effective range of the upper disc-type eddy current stator 61. The upper high static stiffness module 6 interacts with the corresponding annular magnetic plate 63, generating an upward electromagnetic attraction force F. h2 Therefore, the resultant electromagnetic force within this interval is F. l +Fh2 .

[0071] As can be seen from the above working process, within the interval [y1, y3] near the static equilibrium position y2, the vibration isolator mainly relies on the low dynamic stiffness module 4 for support, resulting in low system dynamic stiffness, which is beneficial for meeting low-frequency vibration isolation requirements. However, in the interval near the upper and lower boundaries, the high static stiffness module 6 intervenes in a timely manner and provides boundary constraint forces, thereby helping to limit further displacement and improve working stability under large stroke conditions. Simultaneously, when the vibration isolation load or external working conditions change, the operating parameters of the low dynamic stiffness module 4 and the high static stiffness module 6 can be adjusted by the controller to change the electromagnetic support constant force and boundary constraint forces, enabling the device to better adapt to the quasi-zero stiffness vibration isolation requirements under different working conditions, thus improving the problem of insufficient variable load adaptability in existing technologies.

[0072] The controller is electrically connected to both the low dynamic stiffness module 4 and the high static stiffness module 6. The controller adjusts the operating parameters of the low dynamic stiffness module 4 to change the electromagnetic support constant force generated by the electromagnetic coupling between the short primary winding 42 and the long secondary winding 41. Simultaneously, the controller also adjusts the operating parameters of the high static stiffness module 6 to change the electromagnetic attraction force formed between the disc-type eddy current stator and the annular magnetic plate 63. Thus, the support and boundary constraint effects can be adjusted separately according to different load conditions and displacement states. Compared with a quasi-zero stiffness vibration isolation structure with fixed parameters, this method is beneficial for improving the device's adaptability to variable load conditions.

[0073] In some preferred embodiments, a gravity sensor is installed on the loading platform 1, electrically connected to the controller, to detect the current load information. The controller adjusts the current parameter of the low dynamic stiffness module 4 based on the detected load information, ensuring that the electromagnetic support constant force output by the low dynamic stiffness module 4 matches the load gravity. When the load increases, the controller increases the current parameter of the low dynamic stiffness module 4 to enhance the electromagnetic support constant force; when the load decreases, the controller decreases the current parameter of the low dynamic stiffness module 4 to reduce the electromagnetic support constant force. Through this method, the device can maintain the corresponding support state under different load masses, avoiding significant deviations in the operating point due to load changes, thereby improving the problem of insufficient adaptability of existing structures to variable loads.

[0074] During operation, the low dynamic stiffness module 4 and the high static stiffness module 6 can form a segmented quasi-zero stiffness working state. Specifically, within the equilibrium range, the low dynamic stiffness module 4 outputs a constant electromagnetic support force to counteract the gravity of the load. At this time, the high static stiffness module 6 does not play a major role, and the system exhibits low dynamic stiffness, which is beneficial for isolating low-frequency vibrations. When the motor housing 43 deviates from the equilibrium range and approaches the upper and lower boundaries, the corresponding high static stiffness module 6 begins to output electromagnetic attraction, forming a boundary constraint force to limit the displacement from increasing further. In this way, the device can maintain the low stiffness characteristics required for vibration isolation within the intermediate working range, while obtaining additional stabilizing effect when the displacement approaches the boundary, which is beneficial for balancing vibration isolation performance and operational stability under large stroke conditions.

[0075] Furthermore, since both the low dynamic stiffness module 4 and the high static stiffness module 6 operate electromagnetically, the controller can adjust their parameters separately. Therefore, it can perform matched control according to different operating bandwidths, load levels, and displacement states. This setup not only helps achieve adjustable vibration isolation over a wider frequency range but also provides a foundation for the device to maintain a relatively stable operating state under complex conditions.

[0076] In a preferred embodiment, the long secondary 41 includes a coaxially arranged cylindrical iron secondary 411 and a cylindrical copper secondary 412. The cylindrical iron secondary 411 is fixedly disposed between the upper cover plate 2 and the lower cover plate 3, and the cylindrical copper secondary 412 is fitted onto the outer surface of the cylindrical iron secondary 411. With the above structure, the cylindrical iron secondary 411 can form a relatively stable mounting foundation, which is beneficial for sealing the magnetic circuit and enhancing the magnetic field; the cylindrical copper secondary 412 is disposed outside the cylindrical iron secondary 411, which facilitates electromagnetic coupling with the external short primary 42, thereby providing conditions for the low dynamic stiffness module 4 to generate electromagnetic support constant force. At the same time, the coaxial arrangement of the cylindrical iron secondary 411 and the cylindrical copper secondary 412 is beneficial for concentrating the electromagnetic effect along the vibration isolation direction and reducing the adverse effects of eccentric force on vibration isolation performance.

[0077] Furthermore, the short primary 42 includes a cylindrical linear induction motor stator core 421 and a three-phase AC winding 422 embedded in the cylindrical linear induction motor stator core 421. The cylindrical linear induction motor stator core 421 is used to guide and concentrate the magnetic field. After the three-phase AC winding 422 is energized, it forms a traveling wave magnetic field and electromagnetically couples with the long secondary 41, thereby generating a constant electromagnetic support force along the vibration isolation direction. This structure allows the short primary 42 to form a relatively concentrated electromagnetic action area within a limited space, enabling the low dynamic stiffness module 4 to stably output the constant electromagnetic support force to counteract the load gravity within the equilibrium range, thus providing a foundation for a working state with low dynamic stiffness.

[0078] In this embodiment, the short primary 42 is sleeved outside the long secondary 41 and fixedly connected to the motor housing 43, so as to float synchronously with the motor housing 43 along the vibration isolation direction. The motor housing 43 serves as the main load-bearing structure, used to support, fix, and protect the short primary 42. Through the above arrangement, on the one hand, a stable coaxial fit relationship can be maintained between the short primary 42 and the long secondary 41, which is beneficial to maintaining the stability of the electromagnetic coupling process; on the other hand, the short primary 42 moves synchronously with the motor housing 43, which facilitates the low dynamic stiffness module 4 to continuously output support at different displacement positions. Combined with the constraint of the guide rod 5 on the movement direction of the motor housing 43, the short primary 42 can move mainly along the vibration isolation direction relative to the long secondary 41, thereby helping to reduce the sway effect under large stroke conditions and maintain the stable operation of the device.

[0079] Specifically, after the three-phase AC winding 422 is energized, it generates a traveling wave magnetic field. This traveling wave magnetic field cuts the cylindrical copper secondary winding 412 and induces eddy currents on its surface. The induced eddy currents interact with the traveling wave magnetic field, thereby generating an electromagnetic support constant force along the vibration isolation direction on the short primary winding 42. This electromagnetic support constant force cancels out the gravity of the vibration isolator load, allowing the low dynamic stiffness module 4 to bear the main support role within the equilibrium range. When there is external vibration excitation and the relevant components are displaced within the equilibrium range, since gravity and the electromagnetic support constant force are basically balanced, and the high static stiffness module 6 does not participate in the main role at this time, the system dynamic stiffness is low, which is beneficial for achieving low-frequency vibration isolation.

[0080] In a preferred embodiment, the high static stiffness module 6 includes an upper disc-type eddy current stator 61 and a lower disc-type eddy current stator 62. The upper disc-type eddy current stator 61 is disposed on the inner surface of the upper cover plate 2 and corresponds to the annular magnetic guide plate 63 fixed to the upper surface of the motor housing 43; the lower disc-type eddy current stator 62 is disposed on the inner surface of the lower cover plate 3 and corresponds to the annular magnetic guide plate 63 fixed to the lower surface of the motor housing 43. This corresponding upper and lower arrangement allows the high static stiffness module 6 to function when the motor housing 43 deviates upwards or downwards from the equilibrium range, thereby forming symmetrical boundary constraints on both sides in the vertical direction. This helps to maintain the low dynamic stiffness characteristics in the middle working range while improving the operational stability of the device under large stroke conditions.

[0081] Furthermore, the upper disc-type eddy current stator 61 and the lower disc-type eddy current stator 62 adopt the same structure, both including several stator cores 64 and several DC coils 65 respectively surrounding each stator core 64. The several stator cores 64 and their corresponding DC coils 65 are arranged circumferentially around the cylindrical iron secondary 411 to form a disc-type eddy current stator. With the above structure, the disc-type eddy current stator can form a distributed electromagnetic action area along the circumference of the cylindrical iron secondary 411, which is beneficial to improving the uniformity of the force distribution between the stator and the corresponding annular magnetic plate 63, reducing the adverse effect of local force concentration on motion stability, and helping the corresponding annular magnetic plate 63 to enter the effective action range of the corresponding disc-type eddy current stator more stably when the motor housing 43 undergoes vertical displacement.

[0082] In the initial equilibrium state, due to the large distance between the upper disc-type eddy current stator 61, the lower disc-type eddy current stator 62, and the corresponding annular magnetic plate 63, there is basically no electromagnetic interaction between them. At this time, the device mainly relies on the low dynamic stiffness module 4 to provide the electromagnetic support constant force to counteract the load gravity, while the high static stiffness module 6 does not participate in the main function. With this setting, the support function within the equilibrium range can be mainly undertaken by the low dynamic stiffness module 4, which is conducive to maintaining a low dynamic stiffness.

[0083] When the system is subjected to disturbances or load changes, the motor housing 43 will displace in the vibration isolation direction. If the disturbance or load change is small, the motor housing 43 remains within the equilibrium range, and the high static stiffness module 6 does not play a major role; the system mainly relies on the support of the low dynamic stiffness module 4 to maintain its operating state. If the disturbance or load change is large, the motor housing 43 deviates from the equilibrium range and enters the effective range of the corresponding disc-type eddy current stator. In this case, the corresponding annular magnetic plate 63 fixed on the motor housing 43 will interact electromagnetically with the corresponding disc-type eddy current stator, generating an electromagnetic attraction force in the corresponding direction, thus forming a boundary constraint force. This boundary constraint force is used to suppress further displacement of the motor housing 43 and promote its return to the equilibrium range. Therefore, the high static stiffness module 6 only intervenes when deviating from the equilibrium range, and can cooperate with the low dynamic stiffness module 4 in different operating ranges, thereby improving the operational stability under large displacement conditions.

[0084] Furthermore, by changing the current parameters of the DC coil 65 in the disc-type eddy current stator, the magnitude of the boundary constraint force formed by the high static stiffness module 6 can be altered. Therefore, the constraint characteristics of the high static stiffness module 6 can be adjusted according to different loads and vibration isolation requirements, allowing it to better match the current operating conditions and thus improving the device's adaptability to different conditions.

[0085] In a preferred embodiment, four guide rods 5 are provided, and the four guide rods 5 are evenly distributed at 90° around the central axis of the long secondary stage 41. The four guide rods 5 are respectively connected to the upper cover plate 2 and the lower cover plate 3, and slide in engagement with the motor housing 43 to guide the movement of the low dynamic stiffness module 4. By adopting the method of evenly distributing the four guide rods 5 around the central axis of the long secondary stage 41, the movement constraint of the low dynamic stiffness module 4 in the vibration isolation direction can be more balanced, which is beneficial to reducing sway and tilt during the movement process, thereby improving the operating stability of the device under large stroke conditions. At the same time, the symmetrical arrangement of the four guide rods 5 along the central axis also makes it easier to keep the movement direction of the low dynamic stiffness module 4 consistent with the direction of action of the electromagnetic support constant force, thereby helping to maintain the force coordination during the vibration isolation process.

[0086] Furthermore, four support rods 7 are provided, evenly distributed at 90° angles around the central axis of the long secondary module 41, and the four support rods 7 and the four guide rods 5 are staggered in the circumferential direction. The four support rods 7 are used to transfer the weight of the load-bearing object to the low dynamic stiffness module 4, so that the loading platform 1 and the low dynamic stiffness module 4 move together. With the above arrangement, on the one hand, the support rods 7 can transfer the load on the loading platform 1 to the motor housing 43 and the low dynamic stiffness module 4 more evenly, which helps to reduce the adverse effects of local force concentration on motion stability; on the other hand, the staggered arrangement of the support rods 7 and the guide rods 5 in the circumferential direction can take into account both load-bearing and force transmission and motion guidance functions in a limited space, avoiding mutual interference between the two in the structural arrangement, thereby improving the compactness and stress stability of the overall structure.

[0087] During operation, the loading platform 1 is linked to the low dynamic stiffness module 4 via four support rods 7. When the load changes or the system is subjected to external disturbances, the loading platform 1 can move synchronously with the low dynamic stiffness module 4. Simultaneously, the four guide rods 5 constrain the motion trajectory of the low dynamic stiffness module 4, causing it to primarily displace along the vibration isolation direction. Thus, the support rods 7 are responsible for relatively stable load transmission, while the guide rods 5 are responsible for relatively stable constraint of the motion direction. Their cooperation helps ensure that the low dynamic stiffness module 4 outputs a relatively stable electromagnetic support constant force within the equilibrium range, and provides a relatively stable motion foundation for the high static stiffness module 6 to exert its constraint effect in the boundary region. Through this structural design, the performance degradation of existing vibration isolators under large stroke conditions caused by uneven force distribution or insufficient guidance can be improved to a certain extent.

[0088] Example 2

[0089] The present invention also provides a control method based on the wideband adjustable electromagnetic quasi-zero stiffness vibration isolator described in Embodiment 1, which is used to coordinate the segmented action relationship between the low dynamic stiffness module 4 and the high static stiffness module 6, so that the device maintains the corresponding vibration isolation working state under different loads and different displacements, thereby improving the problems of insufficient adaptability of existing quasi-zero stiffness vibration isolators to variable load conditions and decreased stability under large stroke conditions.

[0090] Specifically, the control method includes the following steps:

[0091] S1. Obtain the load information of the load carried by the vibration isolator, and control the low dynamic stiffness module 4 to output the electromagnetic support constant force along the vibration isolation direction according to the load information, so that the electromagnetic support constant force matches the load gravity, so as to establish the balanced working state of the vibration isolator.

[0092] Specifically, the load information of the vibration isolator currently bearing the load can be obtained by a gravity sensor installed on the loading platform 1, and the load information can be sent to the controller. Based on the obtained load information, the controller adjusts the operating parameters of the low dynamic stiffness module 4 so that the electromagnetic support constant force generated by the electromagnetic coupling between the short primary winding 42 and the long secondary winding 41 matches the current load gravity. Through this control method, the low dynamic stiffness module 4 can establish corresponding support states under different load conditions, thereby keeping the motor housing 43 operating near the equilibrium range. This configuration allows the device to adjust its support function promptly when the load changes, improving its adaptability to variable load conditions.

[0093] S2. Control the high static stiffness module 6 to be in a preset working state, so that the upper high static stiffness module 6 and the lower high static stiffness module 6 have the ability to output boundary constraint force in their respective effective action areas.

[0094] Specifically, the controller sets the operating parameters of the upper disc-type eddy current stator 61 and the lower disc-type eddy current stator 62 so that they can output corresponding electromagnetic attraction when the corresponding annular magnetic plate 63 enters the effective range. At this time, the high static stiffness module 6 does not play a major supporting role within the equilibrium range, but is pre-positioned in a responsive state so as to intervene in time when the motor housing 43 deviates from the equilibrium range. Through the above settings, the high static stiffness module 6 can form a preset boundary constraint capability outside the equilibrium range, thereby providing a basis for motion restriction under large displacement conditions.

[0095] S3. During the operation of the vibration isolator, the position of the motor housing 43 relative to the equilibrium zone is detected. When the motor housing 43 is within the equilibrium zone, the low dynamic stiffness module 4 provides electromagnetic support constant force to counteract the load gravity. When the motor housing 43 deviates from the equilibrium zone and enters the corresponding effective action zone, the high static stiffness module 6 on the corresponding side outputs boundary constraint force, which works together with the low dynamic stiffness module 4 to form a segmented quasi-zero stiffness vibration isolation.

[0096] Specifically, during operation, the controller continuously monitors the position of the motor housing 43 relative to the equilibrium zone. When the motor housing 43 is within the equilibrium zone, the vibration isolator is mainly supported by the electromagnetic constant force provided by the low dynamic stiffness module 4, while the high static stiffness module 6 does not play a major role. At this time, the dynamic stiffness is low, which is beneficial for achieving low-frequency vibration isolation. When external disturbances or load changes cause the motor housing 43 to deviate from the equilibrium zone and enter the effective action zone of the upper or lower high static stiffness module 6, the disc-type eddy current stator on the corresponding side interacts with the annular magnetic plate 63 to generate boundary constraint forces in the corresponding direction, thereby suppressing further displacement of the motor housing 43. Thus, the low dynamic stiffness module 4 undertakes the main support role within the equilibrium zone, while the high static stiffness module 6 undertakes the additional constraint role in the boundary area. The two cooperate in different zones to form a segmented quasi-zero stiffness vibration isolation state.

[0097] In a preferred embodiment, controlling the output of the low dynamic stiffness module 4 to exert a constant electromagnetic support force along the vibration isolation direction based on load information can be achieved by adjusting the current parameters of the low dynamic stiffness module 4 using a controller. Specifically, the controller adjusts the current parameters supplied to the short primary winding 42 to change the constant electromagnetic support force generated by the electromagnetic coupling between the short primary winding 42 and the long secondary winding 41. Preferably, the current parameters include the amplitude and / or frequency of the current supplied to the short primary winding 42. By adopting the above method, the supporting effect of the low dynamic stiffness module 4 can be specifically adjusted according to different load information, allowing the constant electromagnetic support force output by the low dynamic stiffness module 4 to better match the current load gravity. This helps the vibration isolator maintain a balanced working state under different load conditions and improves the problem of insufficient adaptability of existing structures to variable load conditions.

[0098] Further, in step S2, the high static stiffness module 6 is in a preset working state, which can be achieved by adjusting the current parameters of the disc-type eddy current stator through the controller. Specifically, the controller adjusts the magnitude of the DC current flowing through the disc-type eddy current stator so that the disc-type eddy current stator outputs a corresponding electromagnetic attraction force when the corresponding annular magnetic plate 63 enters the effective range. After this setting, the high static stiffness module 6 can form a preset boundary constraint capability outside the equilibrium range, and the boundary constraint force can be adjusted according to different working conditions, so that the high static stiffness module 6 can better play its role in limiting displacement when the motor housing 43 deviates from the equilibrium range.

[0099] When an increase in load is detected, the controller increases the current parameter of the low dynamic stiffness module 4 to enhance the electromagnetic support constant force output by the module. Conversely, when a decrease in load is detected, the controller decreases the current parameter of the low dynamic stiffness module 4 to reduce the electromagnetic support constant force output by the module. Through this adjustment method, the electromagnetic support constant force output by the low dynamic stiffness module 4 can be adjusted accordingly with load changes, thereby enabling the vibration isolator to maintain a relatively stable balanced working state during load changes and preventing significant shifts in the operating point due to load variations.

[0100] Furthermore, when the motor housing 43 deviates upward from the balance range and enters the effective range of the upper disc-type eddy current stator 61, an electromagnetic attraction is generated by the interaction between the upper disc-type eddy current stator 61 and the corresponding annular magnetic plate 63. When the motor housing 43 deviates downward from the balance range and enters the effective range of the lower disc-type eddy current stator 62, an electromagnetic attraction is generated by the interaction between the lower disc-type eddy current stator 62 and the corresponding annular magnetic plate 63. Thus, the upper high static stiffness module 6 and the lower high static stiffness module 6 can provide corresponding boundary constraint forces when the motor housing 43 deviates upward or downward, respectively, thereby forming a segmented cooperation with the electromagnetic support constant force provided by the low dynamic stiffness module 4 within the balance range. In this way, the device can maintain low dynamic stiffness within the balance range, while obtaining additional constraints in a timely manner when deviating from the balance range, which is beneficial for balancing low-frequency vibration isolation requirements and operational stability under large stroke conditions.

[0101] By adjusting the current parameters of the low dynamic stiffness module 4 and the high static stiffness module 6 respectively, the low dynamic stiffness module 4 can assume a supporting role matching the load gravity, while the high static stiffness module 6 can provide a constraint role adapted to the working conditions in the boundary region. Thus, the low dynamic stiffness module 4 and the high static stiffness module 6 can work synergistically in different operating ranges, enabling the vibration isolator to better adapt to the quasi-zero stiffness vibration isolation requirements under different load levels and displacement states.

[0102] Using the above control method, the supporting effect of the low dynamic stiffness module 4 can be matched and adjusted according to the load change, and then the boundary constraint effect of the high static stiffness module 6 can be selectively activated according to the displacement state of the motor housing 43. In this way, it is not only beneficial to maintain a low dynamic stiffness of the device within the equilibrium range, but also beneficial to provide additional constraints in a timely manner when the displacement approaches the boundary, thereby taking into account the low-frequency vibration isolation requirements and the operational stability under large stroke conditions to a certain extent.

[0103] Example 3

[0104] This invention also provides a wideband adjustable electromagnetic quasi-zero stiffness vibration isolation platform, such as... Figure 6As shown, the system includes a base 02, a vibration isolation platform 03, and several broadband adjustable electromagnetic quasi-zero stiffness vibration isolators 01 arranged vertically from bottom to top. The vibration isolators 01 are the broadband adjustable electromagnetic quasi-zero stiffness vibration isolators 01 described in Embodiment 1. All vibration isolators 01 are located between the base 02 and the vibration isolation platform 03, with both ends hinged and fixed to the base 02 and the vibration isolation platform 03, respectively.

[0105] In this embodiment, there are 8 vibration isolators 01, arranged in a Stewart parallel mechanism topology: the 8 vibration isolators are divided into 4 groups, with 2 in each group arranged in a cross-sloping manner to form a symmetrical parallel support structure. The upper ends of all vibration isolators 01 are hinged to the lower surface of the vibration isolation platform 03 via ball joints, and the lower ends are hinged to the upper surface of the base 02 via ball joints. The base 02 and the vibration isolation platform 03 are both coaxial circular flat plate structures, and their hinge installation positions are evenly and symmetrically distributed along the circumference to ensure uniform stress on the platform as a whole and avoid vibration isolation performance degradation caused by uneven installation.

[0106] In actual use, the equipment to be isolated is fixed on the upper surface of the vibration isolation table 03, and the base 02 is fixed on the mounting foundation. Each vibration isolator 01 can be independently adjusted in terms of parameters. By adjusting the input current inside the vibration isolator 01, the static load capacity and quasi-zero stiffness range of the corresponding vibration isolator 01 can be adjusted individually to adapt to the weight and distribution of the load on the vibration isolation table 03, ensuring that each vibration isolator 01 works in the optimal vibration isolation range. At the same time, through the coordinated adjustment of the eight vibration isolators 01, a wide range of adjustment of the overall vibration isolation bandwidth of the platform can be achieved to meet the vibration isolation requirements under different working conditions.

[0107] Through the above structural setup, this platform, relying on a parallel topology and in conjunction with the vibration isolator 01, which has high static and low dynamic stiffness characteristics, can simultaneously achieve full-dimensional broadband vibration isolation with three translational degrees of freedom (X, Y, Z) and three rotational degrees of freedom (X, Y, Z). Furthermore, thanks to the fully electromagnetically adjustable characteristics of the vibration isolator 01, the platform can adapt to different loads and excitation frequencies without replacing any mechanical components, simply by adjusting the input current. This significantly improves the platform's applicability and environmental adaptability, while simplifying the platform's debugging process and reducing the workload of on-site adaptation.

[0108] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A wideband adjustable electromagnetic quasi-zero stiffness vibration isolator, characterized in that, Includes a loading platform, an upper cover plate and a lower cover plate arranged vertically opposite each other; also includes: The low dynamic stiffness module includes a long secondary, a short primary and a motor housing arranged coaxially in sequence. The short primary is floated and sleeved on the outside of the long secondary and nested inside the motor housing. When energized, the short primary is electromagnetically coupled to the long secondary to generate a constant electromagnetic support force along the vibration isolation direction. A guide rod that can slide through the motor housing, with its two ends connected to the upper cover plate and the lower cover plate respectively; The high static stiffness module includes a disc-shaped eddy current stator and an annular magnetic plate disposed on the upper and lower sides of the low dynamic stiffness module. The two annular magnetic plates are fixed to the upper and lower surfaces of the motor housing, respectively. The two disc-shaped eddy current stators are disposed on the inner surfaces of the upper and lower cover plates, respectively. When energized, the disc-shaped eddy current stators interact with the corresponding annular magnetic plates to generate electromagnetic attraction. The controller is electrically connected to the low dynamic stiffness module and the high static stiffness module, respectively. The loading platform is positioned directly above the upper cover plate and is connected to the motor housing via a support rod. The low dynamic stiffness module provides electromagnetic support constant force to counteract the load gravity, while the high static stiffness module provides boundary constraint force when the motor housing deviates from the equilibrium range, so that the vibration isolator forms segmented quasi-zero stiffness characteristics.

2. The broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 1, characterized in that, The long secondary includes a cylindrical iron secondary and a cylindrical copper secondary arranged coaxially; The cylindrical iron secondary is fixedly disposed between the upper cover plate and the lower cover plate, and the cylindrical copper secondary is attached to the outer surface of the cylindrical iron secondary.

3. The broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 1, characterized in that, The short primary includes a cylindrical linear induction motor stator core and a three-phase AC winding embedded in the cylindrical linear induction motor stator core.

4. A broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 1, characterized in that, The short primary is sleeved outside the long secondary and fixedly connected to the motor housing so that it floats synchronously with the motor housing along the vibration isolation direction.

5. A broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 1, characterized in that, The high static stiffness module includes an upper disc eddy current stator and a lower disc eddy current stator. The upper disc eddy current stator is disposed on the inner surface of the upper cover plate and is correspondingly disposed with an annular magnetic plate fixed on the upper surface of the motor housing. The lower disc-type eddy current stator is disposed on the inner surface of the lower cover plate and is correspondingly disposed with the annular magnetic plate fixed to the lower surface of the motor housing.

6. A broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 5, characterized in that, The upper disc eddy current stator and the lower disc eddy current stator have the same structure, each including several stator cores, each corresponding to several DC coils surrounding the stator cores, and arranged circumferentially around the cylindrical iron secondary to form a disc eddy current stator.

7. A broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 1, characterized in that, The controller is used to adjust the current parameters of the low dynamic stiffness module to adjust the electromagnetic support constant force output by the low dynamic stiffness module; the controller is also used to adjust the current parameters of the high static stiffness module to adjust the boundary constraint force output by the high static stiffness module.

8. A broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to claim 1, characterized in that, The loading platform is equipped with a gravity sensor electrically connected to the controller for detecting load information; The controller adjusts the current parameters of the low dynamic stiffness module based on the load information detected by the gravity sensor, so that the electromagnetic support constant force output by the low dynamic stiffness module matches the load gravity.

9. A control method for a broadband adjustable electromagnetic quasi-zero stiffness vibration isolator according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Obtain the load information of the load carried by the vibration isolator, and control the low dynamic stiffness module to output the electromagnetic support constant force along the vibration isolation direction according to the load information, so that the electromagnetic support constant force matches the load gravity, so as to establish the balanced working state of the vibration isolator. S2. Control the high static stiffness module to be in a preset working state, so that the upper high static stiffness module and the lower high static stiffness module have the ability to output boundary constraint force in their respective effective action areas. S3. During the operation of the vibration isolator, the position of the motor housing relative to the equilibrium zone is detected. When the motor housing is within the equilibrium zone, the low dynamic stiffness module provides electromagnetic support constant force to counteract the load gravity. When the motor housing deviates from the equilibrium zone and enters the corresponding effective action zone, the high static stiffness module on the corresponding side outputs boundary constraint force, which works together with the low dynamic stiffness module to form a segmented quasi-zero stiffness vibration isolation.

10. A broadband adjustable electromagnetic quasi-zero stiffness vibration isolation platform, comprising a base and a vibration isolation platform from top to bottom, characterized in that, It also includes several broadband adjustable electromagnetic quasi-zero stiffness vibration isolators as described in any one of claims 1-8, wherein the several vibration isolators are disposed between the base and the vibration isolation table, and their two ends are respectively hinged and fixed to the base and the vibration isolation table.

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