Electromagnetic inertial actuator

Abstract

The application provides an electromagnetic inertial actuator, permanent magnets, inner yoke iron and outer yoke iron are fixedly connected by using non-magnetic retainer, so that only ampere force exists in the magnetic circuit system, and good output linearity of the actuator is ensured. On this basis, disc-shaped spring plates with quasi-zero stiffness characteristics are arranged, the inherent frequency of the system is reduced, and low-frequency output performance is ensured. The permanent magnets, the inner yoke iron, the outer yoke iron, the end cover and the heat dissipation device are integrally designed, a large inertial actuator mover mass is formed, the effective mass of the actuator, i.e. the ratio of the mass of the movable part to the total mass, is maximized. In this way, the low-frequency output and the output value per unit mass can be improved, the total volume and mass of the inertial actuator are effectively reduced, and the installation space is saved. Meanwhile, increasing the mass of the mover can effectively reduce the low-frequency vibration displacement of the inertial actuator, and the quasi-zero stiffness characteristics can be further ensured to be realized and stable.

Description

Technical Field

[0001] This invention relates to the field of active vibration reduction technology, and more specifically, to an electromagnetic inertial actuator. Background Technology

[0002] With the continuous development of science and technology, people's requirements for vibration control are also increasing. While traditional passive control technology has advantages such as simple structure and ease of implementation, its control effect can no longer be further improved and cannot fully meet people's needs. Active vibration control, on the other hand, can adapt to changes in external disturbance frequency and has excellent control effects, gradually becoming the development trend of vibration control technology. Active vibration control refers to the process of applying a certain control strategy based on the detected vibration signal during vibration control, performing real-time calculations, and then driving actuators to exert a certain influence on the control target to achieve the purpose of suppressing or eliminating vibration.

[0003] Actuators are key components for active control and crucial links in active control systems. Their function is to apply control forces to the controlled object according to a defined control law, thereby altering the system's vibration response. Inertial actuators, sometimes called active vibration absorbers, work by converting electrical energy into mechanical energy from an external power source. This mechanical energy causes the inertial actuator's moving mass to reciprocate, generating a driving force with specific amplitude, frequency, and phase. This force is applied to the moving mass of the main system, canceling out the excitation force on the main system's moving mass and thus suppressing the main system's vibration. Currently, the most widely used inertial actuator structures are piezoelectric, magnetostrictive, and electromagnetic. Electromagnetic actuators, in particular, offer advantages such as fast response, simple structure, high actuation force, low driving current, and wide applicability, making them widely used in active control. Electromagnetic inertial actuators are further divided into moving-magnet and moving-coil types. A moving coil refers to a coil acting as the inertial mass, while a moving magnet refers to a magnet acting as the inertial mass. Among them, the moving magnet type inertial actuator can have a large inertial mass because it is easy to make the inertial mass large, thus ensuring that the actuator outputs a large inertial force.

[0004] An electromagnetic actuator includes a stator and a mover. The stator includes an excitation coil, and the mover includes a permanent magnet and a magnetic plate. When energized, the excitation coil is subjected to an Ampere force in the magnetic field. When the current is alternating current, the Ampere force acts alternately in the up and down directions, driving the mover to vibrate up and down, forming an inertial force that cancels out the external excitation force on the controlled object, thereby suppressing the vibration of the controlled object.

[0005] The following patents were found to be related to electromagnetic actuators.

[0006] 1. Patent title: Resonant line spectrum inertial actuator, active control system and control method, application number: 201811589162.8, applicant: Xi'an Jiaotong University.

[0007] 2. Patent Name: A Quasi-Zero Stiffness Inertial Actuator, Application No.: 201621422588.0, Applicant: Suzhou Dongling Intelligent Vibration Reduction and Noise Reduction Technology Co., Ltd.

[0008] 3. Patent Name: Integrated Inertial Electromagnetic Actuator, Application No.: 201410055324.5, Applicant: Harbin Engineering University.

[0009] 4. Patent Name: Moving Magnet Inertial Actuator, Application No.: 201220498060.7, Applicant: 711 Research Institute of China Shipbuilding Industry Corporation.

[0010] 5. Patent title: A series extended inertial actuator, application number: 201721469528.9, applicant: Xi'an Jiaotong University.

[0011] 6. Patent title: A pair-mounted integrated inertial actuator, application number: 201921136958.8, applicant: Xi'an Jiaotong University.

[0012] 7. Patent Name: A Composite Electromagnetic Dynamic Vibration Absorber, Application No.: 201922485495.2, Applicant: Zhongke Zhensheng (Suzhou) Electronic Technology Co., Ltd.

[0013] 8. Patent Name: An Electromagnetic Active Vibration Absorber, Application No.: 202220432717.3, Applicant: Zhongke Zhensheng (Suzhou) Electronic Technology Co., Ltd.

[0014] 9. Patent title: An electromagnetic active vibration absorber, application number: 201720827826.4, applicant: Wuhan Yuanhai Bocheng Technology Co., Ltd.

[0015] 10. Patent title: An electromagnetic active vibration absorber, application number: 201910859524.9, applicant: South China University of Technology.

[0016] 11. Patent Name: Vibratory acoustic compressor, Application No.: US19920904210A, Applicant: HARMAN INT IND.

[0017] 12. Patent title: Force actuator with dual magnetic operation, application number: US19970998731A, applicant: MOTRAN IND INC.

[0018] 13. Patent Name: Inertial voice type coil actuator, Application No.: US20040995145A, Applicants: VINCENT STEPHEN S; KATZ ROBERT; DUCHESNE SYLVAIN.

[0019] Analysis of the above patents reveals that existing inertial actuator technology generally suffers from the following problems and drawbacks:

[0020] 1) The natural frequency of inertial actuators in the prior art is relatively high, resulting in low output at low frequencies and limiting the operating frequency range of the product; or the existing technology used when designing inertial actuators with lower natural frequencies will increase the system size, weight and complexity and bring other adverse effects.

[0021] 2) In the existing technology, the inertial actuator has a small output per unit volume mass, which means that in order to achieve the set vibration reduction effect, the actuator structure is more complex and the size and weight are larger, which limits the practical application of the product.

[0022] 3) The magnetic circuit structure design of the inertial actuator in the existing technology is unreasonable, resulting in poor output linearity and affecting the effect of active vibration control; in addition, the moving magnet structure design is prone to the problem of mover eccentricity, causing assembly difficulties. When eccentric, the mover and stator will collide, reducing the reliability of the equipment. The collision will generate friction and vibration, causing the output-displacement linearity to deviate from the ideal value.

[0023] 4) Existing inertial actuators lack heat dissipation devices, resulting in excessive temperature rise during operation, which limits the output performance of the product and affects its reliability.

[0024] Of the 13 patents mentioned above, the first patent discloses a resonant line spectrum inertial actuator, an active control system, and a control method. Its purpose is to use a harmonic oscillator to lock the output vibration within the resonant region of the inertial oscillator, achieving a larger output force with a smaller electromagnetic driving force. Its structure includes a shell, coil, oscillator, adjustable stiffness spring system, harmonic oscillator, and power amplifier. The oscillator includes a magnetic plate, permanent magnet, guide post, and counterweight, collectively forming the mover mass. This solves the second technical problem mentioned above. However, this technical solution designs the inner and outer yokes as an integrated magnetic structure (i.e., the upper, middle, and lower magnetic plates are integrated). In addition to the Ampere force, the magnetic circuit structure is also subject to the electromagnetic attraction generated by the electromagnet (this electromagnetic force is related not only to the current magnitude but also to the air gap length), causing the mover to become eccentric. This leads to the third technical problem during the mover's movement, exhibiting force-displacement nonlinearity. The first patent addresses the first technical problem mentioned above by reducing the natural frequency of the inertial actuator suspension system through quasi-zero stiffness technology, thereby improving the low-frequency and even ultra-low-frequency output performance of the actuator. However, its spring system, which uses the Euler compression rod principle, cannot be radially positioned and requires a separate linear bearing for guidance. This leads to friction during operation and increases the system's size and complexity. None of the 13 patents mentioned above address the fourth technical problem. Summary of the Invention

[0025] The technical problem to be solved by the present invention is to address the shortcomings of existing technologies, which increase the mass of the mover and improve the low-frequency output characteristics by fixing the permanent magnet together with the inner and outer yokes, but the output-displacement linearity is low, and reduce the natural frequency of the inertial actuator suspension system by using quasi-zero stiffness technology, but the structure is complex. The present invention provides an electromagnetic inertial actuator that has both a high output value per unit mass of the mover and high output-displacement linearity, as well as quasi-zero stiffness characteristics and a simple structure.

[0026] The above-mentioned objectives of the present invention are achieved through the following technical solutions:

[0027] An electromagnetic inertial actuator includes a mover and a stator. The mover includes a permanent magnet, an inner yoke, and an outer yoke. The stator includes an excitation coil and a coil mounting frame. The inner yoke includes inner yoke one and inner yoke two, which are connected in series to form the inner core of the mover. The outer yoke is radially surrounded by the inner core of the mover, and the outer yoke is connected to the inner core of the mover by a cage made of non-magnetic material. The excitation coil is located between the outer yoke and the inner core of the mover, and has gaps between itself and the outer yoke, the inner core of the mover, and the cage.

[0028] To achieve high output-displacement linearity, the following settings are implemented: 1. Inner yoke one, permanent magnet, and inner yoke two are sequentially connected in series to form a single unit, ensuring structural stability; 2. The inner core of the mover and the outer yoke are then fixedly connected using a cage, preventing the excitation coil from attracting the inner and outer yokes together, and maintaining a fixed gap between the inner and outer yokes; 3. The cage is made of non-magnetic material, ensuring it does not affect the magnetic circuit. These three points ensure that the magnetic circuit structure of the product is only affected by Ampere force, resulting in high output linearity. Furthermore, the fixed gap between the inner and outer yokes facilitates convenient and reliable assembly.

[0029] Before energization, the permanent magnet generates a constant magnetic field, forming closed magnetic lines of force along the inner and outer yokes. After energization, the excitation coil experiences an Ampere force in the magnetic field. When the current is alternating current, the Ampere force acts alternately in the vertical direction, driving the mover part to vibrate up and down, generating an inertial force. This force is transmitted to the controlled object through the central rod, canceling out the external excitation force on the controlled object, thereby suppressing the vibration of the controlled object.

[0030] The permanent magnet of this invention is made of neodymium iron boron material and is axially magnetized. The outer yoke, inner yoke one, and inner yoke two are made of DT4 electrical pure iron material with high magnetic permeability. The cage is made of non-magnetic materials such as high-strength aluminum or stainless steel. The excitation coil is made of enameled wire, and the enameled wire of the upper and lower coils is wound in opposite directions to ensure that the current direction is opposite when energized.

[0031] Preferably, the inner yoke one, the permanent magnet, and the inner yoke two are installed in series, axially locked using a locking nut, and then fixed together on the cage.

[0032] Furthermore, the stator also includes a center rod, with a coil mounting bracket fixed at each end of the center rod, and an excitation coil fixed at each end of the coil mounting bracket; the center rod passes through the coil mounting bracket, the inner core of the mover, and the coil mounting bracket in sequence to connect with the controlled object, wherein the center rod moves through the inner core of the mover.

[0033] The stator includes a center rod, which is not only part of the stator but also plays a role in transmitting vibration. The center rod is used to mount the coil mounting bracket and transmit vibration, making the structure compact while enclosing all stator components within the outer yoke. This makes the outer yoke act like a shell for the actuator, facilitating the increase of the mover's mass.

[0034] Furthermore, it also includes a quasi-zero stiffness device, which is a disc-shaped spring symmetrically arranged at both ends of the central rod. The center of the disc-shaped spring is fixed to the stator, and the edge of the disc-shaped spring is fixed to the mover, thereby connecting the mover and the stator.

[0035] Furthermore, the center of the disc spring is fixed to the center rod of the stator, and the edge of the disc spring is fixed to the outer yoke of the mover.

[0036] Using disc reeds to achieve near-zero stiffness characteristics of the actuator reduces the natural frequency of the inertial actuator, improving the low-frequency and even ultra-low-frequency output of the product without increasing its size, weight, or structural complexity, and also widening the operating frequency range.

[0037] It is also important to note that although there is a gap between the inner core of the mover and the central rod in this invention, the mover will not rub against the central rod when it vibrates up and down. This is because there is no magnetic attraction between the inner core of the mover and the central rod; and because the disc-shaped spring is fixed to the central rod and supported between the outer yokes, and the disc-shaped spring has high radial stiffness, the mover will hardly become eccentric. Therefore, this invention has a compact and ingenious structure, possessing both good quasi-zero stiffness characteristics and high output-displacement linearity.

[0038] Furthermore, the height-to-thickness ratio of the disc-shaped spring structure is...

[0039] Furthermore, it also includes an upper end cover and a lower end cover, with an outer yoke fixed between the upper and lower end covers. The disc-shaped spring, stator, and mover core are all located within the space enclosed by the upper and lower end covers and the outer yoke, with the central rod of the stator passing through the lower end cover and connecting to the controlled object. The upper and lower end covers not only serve a protective function but also connect to the outer yoke, making them part of the mover, increasing the mover mass, and thus significantly improving the output force per unit mass of the mover. In electromagnetic inertial actuators equipped with quasi-zero stiffness devices, increasing the mover mass can effectively reduce the low-frequency vibration displacement of the inertial actuator, further ensuring the realization and stability of quasi-zero stiffness characteristics. The end covers mentioned in this invention refer to the upper and lower end covers. Another ingenious aspect of this invention's structure is that the cooperative structure of the stator and mover allows the outer yoke to connect to the upper and lower end covers, making the end covers part of the mover.

[0040] Furthermore, the end face connecting the outer yoke to the end cap is L-shaped, with the protruding part of the L-shaped end face facing outwards; the corresponding part where the end cap mates with the outer yoke is an inverted L-shape; the disc spring is placed in the recessed part of the L-shaped end face of the outer yoke, and the depth of the recessed part of the L-shaped end face of the outer yoke is equal to the sum of the thickness of the edge of the disc spring and the thickness of the protruding part of the inverted L-shaped end face of the end cap; fasteners are used to pass through the end cap, disc spring, and outer yoke to fix the end cap, disc spring, and outer yoke together. The outer yoke, with its L-shaped end face and the protruding part of the L-shaped end face facing outwards, provides radial limiting for both the end cap and the disc spring, and also facilitates the installation and positioning of the end cap and disc spring.

[0041] Furthermore, a heat dissipation device is fixed to the outside of the outer yoke. This reduces the temperature during product operation, improving its output performance and reliability. Moreover, by installing heat dissipation devices of different sizes, the mover mass can be adjusted within a certain range, broadening the product's performance range. Due to the structure of this invention, a heat dissipation device can be arranged on the outside of the outer yoke. Preferably, it is a detachable heat dissipation device.

[0042] Preferably, the heat dissipation device is a heat sink.

[0043] This invention integrates the permanent magnet, inner and outer yokes, end caps, and heat dissipation device into a single design, resulting in a larger mover mass for the inertial actuator. This maximizes the effective mass of the actuator, meaning the proportion of the moving part's mass to the total mass is high. This improves low-frequency output and output per unit mass, while effectively reducing the overall volume and mass of the inertial actuator, saving installation space. Furthermore, increasing the mover mass effectively reduces low-frequency vibration displacement of the inertial actuator, further ensuring quasi-zero stiffness characteristics and stability.

[0044] The present invention has the following beneficial effects:

[0045] 1) To address the problem of poor linearity in the output of inertial actuators, which affects the effectiveness of active vibration control, this invention utilizes a cage to fix the permanent magnet and the outer yoke, maintaining a constant gap. This prevents the permanent magnet from causing eccentricity in the outer yoke during installation. Furthermore, the cage structure is made of non-magnetic materials such as high-strength aluminum or stainless steel, ensuring that the magnetic circuit structure composed of the permanent magnet and the inner and outer yokes is only subjected to the Ampere force F = BIL, where the force constant BL is generally constant after the structure is determined. Therefore, the electromagnetic thrust of the actuator is linearly related to the current magnitude and independent of the displacement, greatly improving the linearity of the inertial actuator's output. Additionally, the fixed gap between the inner and outer yokes reduces the likelihood of eccentricity and facilitates convenient and reliable assembly.

[0046] 2) In order to solve the problem that the high natural frequency of the inertial actuator suspension system leads to low low-frequency output and limits the operating frequency range of the product, this invention adopts a disc spring structure to achieve quasi-zero stiffness characteristics, thereby reducing the natural frequency of the inertial actuator. Without increasing the size, weight and structural complexity, it improves the low-frequency and even ultra-low-frequency output of the product and widens the operating frequency range.

[0047] 3) To address the problem that low power output density per unit volume of inertial actuators leads to complex structures and large volumes, thus limiting the engineering applications of the products, this invention uses an innovative structural design to fix high-density components such as permanent magnets, inner and outer yokes, upper and lower end covers, and heat sinks together to form the mover part of the actuator. The stator part only contains coils and their supports, which maximizes the mover mass of the inertial actuator, improves the low-frequency power output and the power output per unit volume, and results in a compact and efficient structure.

[0048] 4) To address the adverse effects of excessive heat generation on product performance and lifespan during prolonged operation of inertial actuators, this invention installs heat sinks on the outer side of the actuator's armature. These heat sinks are stamped parts with a multi-grid structure mounted perpendicular to the surface of the outer yoke, resulting in a compact structure and significantly increased heat dissipation area. The heat sinks are easily connected to the outer yoke surface with screws. Furthermore, a thermally conductive medium is applied between the heat dissipation device and the outer yoke to maximize the actuator's heat dissipation speed and effectiveness. Additionally, by installing heat sinks of different sizes and models, the mass of the inertial actuator's mover can be adjusted within a certain range, broadening the product's performance range. Attached Figure Description

[0049] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0050] In the picture:

[0051] Figure 1 This is a schematic diagram of an electromagnetic inertial actuator.

[0052] Figure 2 This is a graph showing the mechanical properties of disc springs with different height-to-thickness ratios z.

[0053] Figure 3 This is a cross-sectional view of the magnetic circuit structure of an electromagnetic inertial actuator.

[0054] Figure 4 This is a structural diagram of a diaphragm disc reed (front view).

[0055] Figure 5 This is a top view of the diaphragm disc reed structure.

[0056] Outer yoke -1; Inner yoke one -2; Permanent magnet -3; Excitation coil -4; Disc spring -5; Upper end cover -6; Locking nut one -7; Locking nut two -8; Center rod -9; Screw -10; Coil bracket -11; Inner yoke two -12; Cage -13; Heat sink -14; Lower end cover -15. Detailed Implementation

[0057] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0058] Example 1

[0059] As can be seen from the background technology, existing electromagnetic inertial actuators mainly suffer from four major problems. This embodiment improves the actuator structure, enabling it to have higher output-displacement linearity, lower frequency output performance, higher output value per unit mass of the actuator, and better heat dissipation. Specific improvements are as follows:

[0060] An electromagnetic inertial actuator includes a mover and a stator, such as Figure 1 As shown, the mover includes a permanent magnet 3, an inner yoke, and an outer yoke 1; the stator includes an excitation coil 4 and a coil mounting bracket 11. The inner yoke includes inner yoke 1 2 and inner yoke 2 12, which are connected in series to form the mover core. The outer yoke 1 is radially surrounded by the mover core, and the outer yoke 1 is connected to the mover core via a cage 13, which is made of a non-magnetic material. The excitation coil 4 is located between the outer yoke 1 and the mover core, and there is a gap between it and the outer yoke 1, the mover core, and the cage 13. The permanent magnet 3 is made of neodymium iron boron and is axially magnetized. The outer yoke 1, inner yoke 1 2, and inner yoke 2 12 are made of DT4 electrical pure iron with high magnetic permeability. The cage 13 is made of non-magnetic materials such as high-strength aluminum or stainless steel. The excitation coil 4 is made of enameled wire, and the winding direction of the enameled wire of the upper and lower coils is opposite to ensure that the current direction is opposite when energized.

[0061] In the prior art described in the background document 1, when energized, the electromagnetic package 8 and the magnetic plate 10 generate electromagnetic attraction, causing the mover to become eccentric. Therefore, this structure causes the mover to exhibit force-displacement nonlinearity during movement. This application effectively solves this technical problem by implementing the following settings to achieve high output linearity: 1. The inner yoke 1, permanent magnet 3, and inner yoke 2 12 are sequentially connected in series to form a whole, stabilizing this part of the structure; 2. The inner core of the mover is then fixedly connected to the outer yoke 1 using a retainer 13, preventing the excitation coil 4 from attracting the inner and outer yokes 1 together, and fixing the gap between the inner and outer yokes 1; 3. The retainer 13 is made of non-magnetic material, so it does not affect the magnetic circuit. These three points ensure that the magnetic circuit structure of the product is only affected by Ampere force, resulting in high output linearity.

[0062] like Figure 1 As shown, inner yoke 12, permanent magnet 3, and inner yoke 212 are installed in series and axially locked using locking nut 7, and then fixed together on cage 13.

[0063] like Figure 1As shown, the stator also includes a central rod 9, with a coil mounting bracket 11 fixed at each end of the central rod 9, and an excitation coil 4 fixed at each end of the coil mounting bracket 11. The central rod 9 passes through the coil mounting bracket 11, the inner core of the mover, and the coil mounting bracket 11 in sequence to connect with the controlled object, wherein the central rod 9 moves through the inner core of the mover.

[0064] It also includes a quasi-zero stiffness device, which consists of disc-shaped springs symmetrically arranged at both ends of the central rod 9. The center of the disc-shaped springs is fixed to the central rod 9 of the stator. Figure 1 As shown, the center of the disc spring 5 is connected to the coil mounting bracket 11 using locking nut 28. The edge of the disc spring 5 is fixed to the outer yoke 1 of the mover. To address the problem that the high natural frequency of the inertial actuator suspension system results in low low-frequency output and limits the product's operating frequency range, this application utilizes a disc spring 5 structure for suspension between the stator and mover of the inertial actuator, reducing the product's natural frequency and improving low-frequency output performance (i.e., increasing the low-frequency output value). Furthermore, the height-to-thickness ratio of the disc spring structure is designed as z.

[0065] like Figure 2 The figure shows the mechanical property curves of disc springs with different aspect ratios. λ1 represents the displacement of disc spring 5 during operation, and P represents the load borne by disc spring 5. Figure 2 The mechanical characteristic curves of disc springs with different thickness ratios z show that by matching the design parameters of the inertial actuator (mass of the mover and stiffness of the disc spring), the system displacement can be made to achieve quasi-zero stiffness characteristics within the range of points A and B. At this time, the natural frequency of the inertial actuator is very low, which can effectively improve its low-frequency output value and broaden the operating frequency range of the product, especially the low-frequency range.

[0066] like Figure 2 As shown, the output of the inertial actuator gradually decreases in the frequency band below its natural frequency. Therefore, reducing the natural frequency as much as possible can effectively increase the output value over a wide frequency range.

[0067] The disc-shaped spring, coil mounting bracket 11, and mover core are arranged vertically, and the outer yoke 1 surrounds the disc-shaped spring, coil mounting bracket 11, and mover core. This structure provides space for increasing the mover mass. This embodiment also includes an upper end cover 6 and a lower end cover 15, with the outer yoke 1 fixed between the upper end cover 6 and the lower end cover 15. The disc-shaped spring, stator, and mover core are all located in the space enclosed by the upper end cover 6, the lower end cover 15, and the outer yoke 1, wherein the central rod 9 of the stator protrudes from the lower end cover 15 and connects to the controlled object. The upper end cover 6 and the lower end cover 15 not only serve a protective function, but their connection with the outer yoke 1 also makes the upper end cover 6 and the lower end cover 15 part of the mover, increasing the mover mass and further improving the output value per unit mass of the mover.

[0068] The end face of the outer yoke 1 connected to the end cap is L-shaped, with the protruding part of the L-shaped end face facing outward; the part of the end cap that mates with the outer yoke 1 is correspondingly inverted L-shaped; the disc spring is placed in the recessed part of the L-shaped end face of the outer yoke 1, and the depth of the recessed part of the L-shaped end face of the outer yoke 1 is equal to the sum of the thickness of the edge of the disc spring and the thickness of the protruding part of the inverted L-shaped end face of the end cap; the end cap, disc spring, and outer yoke 1 are fixedly connected by screws 10 passing through the end cap, disc spring, and outer yoke 1.

[0069] A heat sink 14 is also fixed to the outside of the outer yoke 1. Fasteners are used to pass through the heat sink, outer yoke 1, and retainer 13 in sequence to fix the heat sink, outer yoke 1, and retainer 13 together. The mass of the mover can be adjusted within a certain range by removing and installing the heat sink 14.

[0070] In this embodiment, the mover includes an outer yoke 1, an inner yoke 1 2, a permanent magnet 3, an upper end cover 6, a locking nut 1 7, a screw 10, an inner yoke 2 12, a cage 13, a heat sink 14, and a lower end cover 15. The stator includes an excitation coil 4, a locking nut 2 8, a center rod 9, and a coil support 11. The mover and stator are connected by a disc-shaped spring 5.

[0071] The poor linearity of the inertial actuator's output affects the effectiveness of active vibration control. In this application, the permanent magnet 3, the inner yoke, and the outer yoke 1 are fixedly connected by a non-magnetic cage 13, ensuring only Ampere force in the magnetic circuit system and guaranteeing good linearity of the actuator's output. Furthermore, a disc-shaped spring with quasi-zero stiffness is added to ensure low-frequency output performance. Because there is a gap between the inner core of the mover and the central rod 9, and the outer yoke 1 is supported by the disc-shaped spring, the mover will hardly eccentricate due to the large radial stiffness of the disc-shaped spring, maximizing the stable gap between the inner and outer yokes 1. The disc-shaped spring has both quasi-zero stiffness and a supporting function. As can be seen from the figures in Prior Art Documents 1 and 2, the structures of the two actuators cannot make the end cap and heat sink 14 part of the mover. This application utilizes the actuator's own structure to make the end cap and heat sink 14 part of the mover. The end cap not only functions as an end cap but also contributes to the output value as a mover. The heat sink 14 solves the problem of excessive temperature affecting the output performance and service life of the actuator during long-term operation, and also contributes to the output value. The structure of this application makes the best use of resources, maximizing the effective mass of the inertial actuator's mover part, resulting in a compact and efficient structure. In addition, the inertial actuator also incorporates a disc spring structure based on the quasi-zero stiffness characteristic principle, further improving the low-frequency output value of the product.

[0072] In this embodiment, the inertial actuator is mounted on the vibration control object via the central rod 9. Before power is applied, the permanent magnet 3 generates a constant magnetic field and forms closed magnetic lines of force along the inner and outer yokes 1, such as... Figure 3As shown. After being energized, the excitation coil 44 is subjected to the Ampere force in the magnetic field. When the current is alternating current, the Ampere force acts alternately in the up and down directions, driving the mover part to vibrate up and down, forming an inertial force, which is transmitted to the controlled object through the central rod 9, canceling out the external excitation force on the controlled object, thereby suppressing the vibration of the controlled object.

[0073] The disc-shaped spring 5 structure used in this invention can also be adopted. Figure 4 , Figure 5 The diaphragm disc spring 5 structure shown can achieve the same working principle and effect as this patent.

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the present invention.

Claims

1. An electromagnetic inertial actuator comprising a mover and a stator, the mover comprising a permanent magnet, an inner yoke and an outer yoke, the stator comprising a field coil and a coil mount; characterized in that, The inner yoke iron comprises an inner yoke iron one and an inner yoke iron two, the inner yoke iron one, the permanent magnet and the inner yoke iron two are sequentially connected in series to form a mover inner core; the mover inner core is radially surrounded by an outer yoke iron, the outer yoke iron is connected with the mover inner core through a retainer, the retainer is made of non-magnetic material; the excitation coil is located between the outer yoke iron and the mover inner core and has a gap between the outer yoke iron, the mover inner core and the retainer; The quasi-zero stiffness device is a disc-shaped spring plate symmetrically arranged at both ends of the center rod, the center of the disc-shaped spring plate is fixed with the stator, the edge of the disc-shaped spring plate is fixed with the mover, so as to connect the mover and the stator; the center of the disc-shaped spring plate is fixed with the center rod of the stator, and the edge of the disc-shaped spring plate is fixed with the outer yoke iron of the mover; The height and thickness ratio of the disc spring leaf structure is .

2. The electromagnetic inertial actuator according to claim 1, characterized in that The stator further comprises a center rod, one coil mounting bracket is fixed at each end of the center rod, and an excitation coil is fixed at each end of the coil mounting bracket; the center rod sequentially passes through the coil mounting bracket, the mover inner core and the coil mounting bracket to be connected with the controlled object, wherein the center rod movably passes through the mover inner core.

3. The electromagnetic inertial actuator of claim 1, wherein, The outer yoke iron is fixed between the upper end cover and the lower end cover; the disc-shaped spring plate, the stator and the mover inner core are located in the space surrounded by the upper end cover, the lower end cover and the outer yoke iron, and the center rod of the stator passes through the lower end cover to be connected with the controlled object.

4. The electromagnetic inertial actuator according to claim 3, characterized in that The end surface of the outer yoke iron connected with the end cover is L-shaped, and the protruding part of the L-shaped end surface faces outward; the part corresponding to the part of the end cover matched with the outer yoke iron is inverted L-shaped; the disc-shaped spring plate is placed in the recessed part of the L-shaped end surface of the outer yoke iron, the depth of the recessed part of the L-shaped end surface of the outer yoke iron is equal to the sum of the thickness of the edge of the disc-shaped spring plate and the thickness of the protruding part of the inverted L-shaped end surface of the end cover; a fastener is used to sequentially pass through the end cover, the disc-shaped spring plate and the outer yoke iron to fixedly connect the end cover, the disc-shaped spring plate and the outer yoke iron.

5. The electromagnetic inertial actuator of claim 3, wherein, A heat dissipation device is further fixed on the outer side of the outer yoke iron.

6. The electromagnetic inertial actuator according to claim 5, characterized in that The heat dissipation device is a heat dissipation fin.

7. The electromagnetic inertial actuator according to claim 6, characterized in that A fastener is used to sequentially pass through the heat dissipation device, the outer yoke iron and the retainer to fixedly connect the heat dissipation device, the outer yoke iron and the retainer.

Images