Electromagnetic damping device adopting halbach permanent magnet array

Abstract

The utility model relates to the technical field of damping equipment, in particular to an electromagnetic damping device adopting a halbach permanent magnet array. The method is specifically applied to civil engineering building damping. Comprising a protective shell, and a spring unit, an electromagnetic damping unit and an inerter mass unit are arranged in the protective shell; the electromagnetic damping unit, the inerter mass unit and the spring unit are located on the left side and the right side of the protective shell respectively. According to the electromagnetic damping device adopting the halbach permanent magnet array, relative movement between the halbach permanent magnet array and a conductor is adopted to generate damping force, a mass flywheel and a spring are connected in combination with a gear rack, and mechanical energy is dissipated by generating huge inertial mass and utilizing reciprocating movement of the spring and generating eddy current damping force. According to the device, the spring unit, the inerter unit and the electromagnetic damping unit can operate together through vibration at any end, mechanical energy is consumed, and the purpose of damping is achieved.

Description

Technical Field

[0001] This utility model relates to the field of vibration damping equipment technology, and specifically to an electromagnetic vibration damping device employing a Halbach permanent magnet array. It is applied to vibration damping in civil engineering buildings. Background Technology

[0002] With rapid socio-economic development, building heights are continuously increasing. The widespread use of high-performance building materials has further reduced structural damping, making seismic resistance crucial. Traditional viscous dampers mainly consist of a piston, a sealing ring, and a liquid-filled chamber. When the liquid-filled chamber leaks, the pressure inside the cylinder disappears rapidly, causing a sharp decline or even complete loss of the damper's vibration reduction performance, posing a threat to structural safety. Furthermore, viscous dampers are expensive to manufacture and maintain. In contrast, electromagnetic damping, with its stable high-temperature performance, good durability, and lack of leakage risk, has promising application prospects.

[0003] Single electromagnetic damping is difficult to apply in practical engineering due to its low damping coefficient. The generation mechanism of electromagnetic damping shows that amplifying the relative motion between the magnet and the conductor or strengthening the magnetic field can effectively increase the energy dissipation density of electromagnetic damping. The Halbach permanent magnet array, by arranging magnets in a specific combination, can increase the magnetic field on one side, thereby increasing the energy dissipation of electromagnetic damping.

[0004] Traditional TMD (Transmission Method) systems suffer from the problem of requiring excessively large mass blocks when controlling large structures. These excessively large mass blocks impose enormous loads on the controlled structure and are also very expensive. By combining a mass flywheel with a ball screw drive system, the apparent mass of the flywheel, which initially has a smaller mass, can be magnified to thousands or even tens of millions of times its original mass. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of current TMD (Traction Dampers) development by providing an electromagnetic damping device based on a Halbach permanent magnet array. Through the synergistic action of the drive screw, ball nuts, permanent magnets, and gear rack, compared to conventional electromagnetic damping, the Halbach permanent magnet array enhances the magnetic field strength on one side, amplifying the damping coefficient of the electromagnetic damping component. Simultaneously, the ball nuts amplify the actual mass of the flywheel, with the amplification factor related to the radius ratio of the flywheel and the ball screw. Compared to traditional TMD, this reduces the actual mass of the damper. The amplification factor is: ,in, The rotational torque of the original mass block. For the lead of the ball screw, The acceleration of the ball screw, i.e., the acceleration of the external excitation, is used to increase the upper limit of the damper's working strength. This solves the problems of high cost and long-term performance degradation leading to high maintenance costs associated with viscous dampers, and also addresses the issue of excessively large TMD mass blocks. Overall, this device is more convenient, durable, and has a longer service life, making it suitable for controlling low-frequency vibrations in civil engineering structures.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This utility model provides an electromagnetic vibration damping device using a Halbach permanent magnet array, including a protective shell, and a spring unit, an electromagnetic damping unit, and an inertial mass unit are arranged inside the protective shell; the electromagnetic damping unit is located in the middle of the protective shell, the inertial mass unit is located on the left side of the protective shell, and the spring unit is located on the right side of the protective shell.

[0008] The spring unit includes a rack and a spring; the electromagnetic damping unit includes a gear, a drive shaft, and a Halbach permanent magnet array; the inertial-capacitive mass unit includes a rack, a ball screw, and a mass flywheel.

[0009] A spring is mounted on the rack of the spring unit. One end of the rack extends out of the protective shell, and the other end meshes with the gear of the electromagnetic damping unit. The gear rotates through a drive shaft. A Halbach permanent magnet array is mounted on the outside of the gear, and the gear drives the Halbach permanent magnet array to rotate synchronously. The other side of the gear meshes with one end of the rack of the inertial mass unit. The rack is equipped with a ball screw and a mass flywheel. The gear drives the racks of the inertial mass unit and the spring unit to move synchronously. The other end of the rack of the inertial mass unit extends out of the protective shell. The portions of the racks of the inertial mass unit and the spring unit that extend out of the protective shell are connected to the equipment to be damped.

[0010] The electromagnetic damping unit includes a gear, a drive shaft, a disk, a Halbach permanent magnet array, a conductor, a back iron, and a circular stop. The disk is connected to the gear via the drive shaft. The Halbach permanent magnet array is fixed to the side of the disk. The conductor is fixed to the back iron, and the back iron is fixed to the circular stop. The circular stop is welded to the protective shell, connecting the conductor, the back iron, and the circular stop. There is a certain gap between the Halbach permanent magnet array and the conductor.

[0011] The spring unit includes a rack and a spring; the spring uses two sets of compression springs, with the springs mounted on the rack and a transverse stop on the rack. The protective shell has a stop protrusion, and a spring is placed between the transverse stop and the stop protrusion. When the rack moves forward, one spring is compressed by the transverse stop and bears pressure, while the other spring is not subjected to force.

[0012] The inertial-capacitance mass unit includes a rack, a ball screw, and a mass flywheel; the spring unit includes a linear bearing, a spring, a rack, and a lateral retainer; the rack is connected to the protective shell via the linear bearing, and the lateral retainer is welded to the rack; the inertial-capacitance mass unit consists of a transmission screw, a ball nut, balls, a fixed bearing on the outside of the nut, and a mass flywheel, forming a transmission system with a ball screw; the mass flywheel is mounted on the outside of the ball nut, and when the ball screw is fed linearly, it drives the ball nut to rotate via the balls, which in turn drives the mass flywheel to rotate, while the ball screw itself does not rotate; the force is borne by the ball screw transmission system.

[0013] The two compression springs are located between the transverse stop and the stop protrusion, respectively.

[0014] It also includes a negative stiffness component, which consists of two sets of Halbach permanent magnet arrays. One set of Halbach permanent magnet arrays is located at one end of the rack of the inertial-capacitive mass unit, and the other set of Halbach permanent magnet arrays is located on the protective shell. The two sets of Halbach permanent magnet arrays are arranged in parallel, and the corresponding NN or SS poles are in a state of magnetic repulsion.

[0015] The conductor is made of a high-conductivity material, such as aluminum or copper; the Halbach permanent magnet array uses neodymium iron boron permanent magnets.

[0016] The electromagnetic damping unit has two sets of electromagnetic damping components in its disk, Halbach permanent magnet array, conductor, and back iron. The two sets of electromagnetic damping components are located at both ends of the transmission shaft, and the gear is located in the middle of the transmission shaft.

[0017] A gap is provided between the Halbach permanent magnet array and the conductor, and a gap is provided in the electromagnetic damping component. The gaps are connected to form an air gap cavity.

[0018] Furthermore, an electromagnetic damping device based on a Halbach permanent magnet array includes a spring unit, an inertial mass unit, and an electromagnetic damping unit. The spring unit comprises a rack and two sets of tension springs, one end of which is connected to the rack, and the other end to a protective shell. The inertial mass unit includes a drive screw, a ball nut, a fixed bearing, and a mass flywheel. To ensure that the mass flywheel can rotate while the protective shell remains stationary, the mass flywheel is mounted on the outside of the ball nut, and the fixed bearing is mounted between the outside of the ball nut and the protective shell. The electromagnetic damping unit includes a gear, a disk, a drive shaft, a back iron, a conductor, and a Halbach permanent magnet array. The disk is connected to the gear via the drive shaft, the Halbach permanent magnet array is fixed to the side of the disk, and the conductor is fixed to the protective shell. One end of the rack is a circular rod, and the other end is a rack, which is fixed to the protective shell via a linear bearing. The rack contacts the gear, and when the rack moves linearly, it drives the gear to rotate. One end of the spring is fixed to the disk extending from the circular rod end of the rack, and the other end is connected to the protective shell. When the rack moves, the spring follows the rack in an elastic motion. One end of the transmission screw is a ball groove, and the other end is a rack. When the transmission screw moves linearly, it drives the ball nut to rotate via the balls, which in turn drives the mass flywheel to rotate, amplifying the mass; simultaneously, it drives the gear to rotate via the rack. The ball nut is connected to the protective shell via a fixed bearing.

[0019] Furthermore, the gear is connected to a rack on one side and a transmission screw on the other. When the gear rotates, it drives the disk to rotate via the transmission shaft. The Halbach permanent magnet array is fixed to the side of the disk, the conductor is fixed to the back iron, the back iron is fixed to the protective shell, and the conductor remains stationary. When the disk rotates, it drives the Halbach permanent magnet array to rotate, the conductor cuts the magnetic field lines, generating eddy currents within the conductor, and simultaneously generating a Lorentz force that opposes the rotation of the conductor. The magnet is generally a neodymium iron boron permanent magnet; if a greater magnetic field strength is required, an electromagnet should be used. The conductor is made of excellent conductive materials, such as copper or aluminum. The working principle of the electromagnetic vibration damping device in this scheme is as follows: when the rack vibrates in a certain direction, the spring will be stretched and compressed in the corresponding direction, consuming mechanical energy. This energy is transmitted through the rack to the gear, which in turn drives the disk to reciprocate through the transmission shaft. The disk drives the Halbach permanent magnet array to move relative to the conductor. At the same time, the gear drives the transmission screw to reciprocate linearly, which in turn drives the mass flywheel to reciprocate in rotation via the ball nut. When the lead screw vibrates in a certain direction, it drives the mass flywheel to reciprocate through the ball nut, generating a large inertial mass and thus dissipating mechanical energy. Simultaneously, the rack at the other end of the lead screw drives a gear, which in turn drives a disk to reciprocate through a drive shaft. The disk causes the Halbach permanent magnet array to move relative to the conductor. At the same time, the gear drives the rack to reciprocate linearly, and the spring is stretched and compressed in the corresponding direction. When the gear reciprocates due to the vibration of the rack / lead screw, it drives the disk to reciprocate, causing the Halbach permanent magnet array to move relative to the conductor. The conductor cuts the magnetic field lines generated by the magnet, thus generating eddy currents inside the conductor and creating resistance to the magnet. This resistance is transmitted through the gear to the spring and mass flywheel connected to the rack and lead screw, and is converted into the internal energy of the spring and mass flywheel, achieving the purpose of dissipating the mechanical energy of the vibration.

[0020] This case uses a transmission device consisting of gears, racks, and ball screws, which can simultaneously transmit vibrations from any end to the spring unit, inertial capacitance unit, and electromagnetic damping unit, allowing all three to work together to consume the mechanical energy of the vibration and reduce vibration.

[0021] In summary, the electromagnetic damping device employing a Halbach permanent magnet array in this case utilizes the relative motion between the Halbach permanent magnet array and the conductor to generate damping force. Combined with a gear and rack connection between a mass flywheel and a spring, it dissipates mechanical energy by generating a large inertial mass, utilizing the reciprocating motion of the spring, and generating eddy current damping force. This device can achieve vibration reduction by having the spring unit, inertial capacitance unit, and electromagnetic damping unit work together to dissipate mechanical energy through vibration at either end. Compared to the TMD (Transient Damping Device) which uses a mass flywheel, this design reduces the actual mass of the damper; the virtual mass generated is related to the acceleration at both ends of the damping device. The static friction of the eddy current damper is reduced compared to a viscous damper, resulting in better durability. Furthermore, the electromagnetic damping device using a Halbach permanent magnet array in this case increases the magnetic field strength compared to conventional eddy current dampers, generating a larger eddy current damping force, thus offering significant advantages over both. Traditional viscous dampers face problems such as aging seals, oil leakage, and high maintenance costs, while TMDs face the problem of excessively large mass blocks; the Halbach electromagnetic damper and inertial capacitance unit used in this application effectively solve the above technical problems.

[0022] As a preferred embodiment of this utility model, the transmission lead screw can be changed from the original lead screw-rack to a ball nut-rack-circular rod, and a negative stiffness component formed by a Halbach permanent magnet array arranged regularly with magnets can be installed at the corresponding position of the circular rod.

[0023] Generally, positive stiffness components impede the motion of an object, while negative stiffness components, on the contrary, promote the motion of the object under force. The negative stiffness component formed by the Halbach permanent magnet array, connected to the electromagnetic damping unit and the inertial capacitance unit in this way, is equivalent to interconnection. Therefore, when the transmission screw moves, it increases the lead of the transmission screw, thereby driving the rotation of the Halbach permanent magnet array on the gear and disk, thus increasing the area and speed of conductor cutting, increasing the damping force, and increasing energy consumption. Since the negative stiffness component amplifies the displacement of the device, its addition increases the stroke of the transmission screw and simultaneously amplifies the acceleration of the mass flywheel. The mass flywheel generates a greater inertial force to impede the movement of the transmission screw, achieving the purpose of energy consumption.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0025] This electromagnetic damping device, employing a Halbach permanent magnet array, uses a mass flywheel and a ball screw system to convert linear motion into axial motion, amplifying the actual mass by thousands or even tens of millions of times. Compared to TMD (Transient Damping Device), it can produce an apparent mass equivalent to the actual mass required by TMD, achieving a damping effect comparable to TMD; furthermore, it reduces the actual mass of the damper, facilitating installation in practical engineering and lowering manufacturing costs.

[0026] The electromagnetic damping device using the Halbach permanent magnet array in this scheme employs eddy current damping. Compared to viscous dampers, electromagnetic damping has advantages such as good durability and no leakage risk. Compared to other arrays with the same number of magnets, the Halbach array has a higher air gap magnetic flux density and a higher electromagnetic force, while also achieving a good single-sided magnetic shielding effect, reducing the impact of the magnetic field on the structure.

[0027] This scheme employs a Halbach permanent magnet array electromagnetic damping device that converts the linear motion of the controlled structure into the rotational motion of the electromagnetic damping unit through a gear and rack mechanism. The gear drives the disk to rotate, amplifying the motion and increasing the damping force and energy consumption of the electromagnetic damping unit. Simultaneously, the vibration at one end can drive the electromagnetic damping unit and the unit at the other end to consume energy, achieving the joint operation of the spring unit, inertial capacitance unit, and electromagnetic damping unit to consume mechanical energy and achieve the purpose of vibration reduction. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of this utility model;

[0029] Figure 2 This is a cross-sectional schematic diagram of the electromagnetic damping unit of this utility model;

[0030] Figure 3 A schematic diagram of the Halbach electromagnetic array arrangement;

[0031] Figure 4 A schematic diagram of a structure for adding a Halbach permanent magnet array to form a negative stiffness component;

[0032] Figure 5 A schematic diagram of the application of vibration damping devices to elastic supports;

[0033] Figure 6 This is a schematic diagram of a finite element simulation.

[0034] Figure 7 This is a schematic diagram of the electromagnetic array arrangement;

[0035] Figure 8 This is a schematic diagram of the magnetic flux density mode;

[0036] Figure 9 This is a schematic diagram of the damping force.

[0037] Figure 10 This represents the maximum inter-story drift angle.

[0038] Figure 11 Time history diagram of displacement at the top layer of the structure;

[0039] Figure 12Arrangement of Halbach electromagnetic array positive stiffness components;

[0040] Figure 13 Arrangement of negative stiffness components for Halbach electromagnetic array.

[0041] Icons: 1. Linear bearing; 2. Protective shell; 3. Tension spring; 4. Rack; 5. Gear; 6. Drive shaft; 7. Disc; 8. Permanent magnet; 9. Conductor; 10. Back iron; 11. Air gap cavity; 12. Fixed bearing; 13. Mass flywheel; 14. Ball nut; 15. Ball; 16. Ball screw; 17. Lateral stop; 18. Circular stop. Detailed Implementation

[0042] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0043] The terms "front," "rear," "left," "right," "up," and "down" used in this embodiment description refer to the directions shown in the accompanying drawings. The terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. These terms of orientation or positional relationship are merely for the convenience of description or simplification of the description in the specific embodiments, to facilitate quick understanding of the solution by those skilled in the art, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on this utility model.

[0044] An electromagnetic damping device using a Halbach permanent magnet array includes a protective shell 2, and a spring unit, an electromagnetic damping unit, and an inertial mass unit are arranged inside the protective shell 2; the electromagnetic damping unit is located in the middle of the protective shell 2, the inertial mass unit is located on the left side of the protective shell 2, and the spring unit is located on the right side of the protective shell 2.

[0045] The spring unit includes a rack 4 and a spring 3; the electromagnetic damping unit includes a gear 5, a drive shaft 6, and a Halbach permanent magnet array 8; the inertial-capacitive mass unit includes a rack 4, a ball screw, and a mass flywheel.

[0046] A spring 3 is mounted on the rack 4 of the spring unit. One end of the rack 4 extends out of the protective shell 2, and the other end of the rack 4 meshes with the gear 5 of the electromagnetic damping unit. The gear 5 rotates through the transmission shaft 6. The Halbach permanent magnet array 8 is mounted on the outside of the gear 5, and the gear 5 drives the Halbach permanent magnet array 8 to rotate synchronously. The other side of the gear 5 meshes with one end of the rack 4 of the inertial mass unit. The rack 4 is equipped with a ball screw and a mass flywheel. The gear 5 drives the rack 4 of the inertial mass unit and the spring unit to mesh and move synchronously. The other end of the rack 4 of the inertial mass unit extends out of the protective shell 2. The parts of the rack 4 of the inertial mass unit and the spring unit that extend out of the protective shell 2 are connected to the device to be damped.

[0047] The electromagnetic damping unit includes a gear 5, a drive shaft 6, a disk 7, a Halbach permanent magnet array 8, a conductor 9, a back iron 10, and a circular stop 18. The disk is connected to the gear via the drive shaft. The Halbach permanent magnet array is fixed to the side of the disk. The conductor is fixed to the back iron. The back iron is fixed to the circular stop 18. The circular stop 18 is fixed to the protective shell 2 by welding, connecting the conductor, the back iron, and the circular stop. There is a certain gap between the Halbach permanent magnet array and the conductor.

[0048] The spring unit includes a rack and a spring; the spring uses two sets of compression springs, with a spring mounted on the rack 4, a transverse stop 17 on the rack 4, and a stop protrusion on the protective shell 2. A spring is set between the transverse stop 17 and the stop protrusion. When the rack moves forward, one spring is compressed by the transverse stop 17 and bears pressure, while the other spring is not subjected to force.

[0049] The inertial-capacitance mass unit includes a rack 4, a ball screw, and a mass flywheel; the spring unit includes a linear bearing 1, a spring 3, a rack 4, and a transverse retainer 17; the rack 4 is connected to the protective shell 2 via the linear bearing 1, and the transverse retainer 17 is welded to the rack; the inertial-capacitance mass unit consists of a transmission screw 16, a ball nut 15, balls 14, a fixed bearing 12 on the outside of the nut, and a mass flywheel 13, forming a transmission system with a ball screw; the mass flywheel is installed on the outside of the ball nut, and when the ball screw is fed linearly, it drives the ball nut to rotate via the balls, which in turn drives the mass flywheel to rotate, while the ball screw does not rotate; the force is borne by the ball screw transmission system.

[0050] The two compression springs are located between the transverse stop 17 and the stop protrusion, respectively. A negative stiffness assembly is also included, consisting of two sets of Halbach permanent magnet arrays 8. One set of Halbach permanent magnet arrays 8 is located at one end of the rack 4 of the inertial-capacitive mass unit, and the other set is located on the protective shell 2. The two sets of Halbach permanent magnet arrays 8 are arranged in parallel, with their corresponding NN or SS poles exhibiting magnetic repulsion. The Halbach permanent magnet arrays 8 use neodymium iron boron permanent magnets.

[0051] The electromagnetic damping unit comprises a disk 7, a Halbach permanent magnet array 8, a conductor 9, and a back iron 10, each equipped with two sets of electromagnetic damping components. These two sets of components are located at both ends of the drive shaft 6, with the gear 5 positioned in the middle of the drive shaft 6. A gap exists between the Halbach permanent magnet array 8 and the conductor 9, and the electromagnetic damping components also have gaps, which together form an air gap cavity 11.

[0052] See Figure 1 The electromagnetic damping device using a Halbach permanent magnet array includes a protective shell 2, a spring unit, an electromagnetic damping unit, and an inertial capacitance unit.

[0053] It should be noted that, due to Figure 1 The intermediate gear 5 and the transmission screw 16 shield the structure behind it. Figure 2 The spring unit is not cut out to show the structure of the electromagnetic damping unit.

[0054] The disk is connected to a gear via a drive shaft. A Halbach permanent magnet array is fixed to the side of the disk. The conductor is fixed to a back iron, which is fixed to a circular stop 18. The circular stop 18 is welded to the protective shell 2, connecting the conductor, the back iron, and the circular stop. There is a certain gap between the Halbach permanent magnet array and the conductor. The spring unit includes a rack and a spring. The rack 4 is connected to the protective shell 2 via a linear bearing 1. A transverse stop 17 is welded to the rack. The rack 4 has a transverse stop 17, and the protective shell 2 has a stop protrusion. A spring is installed between the transverse stop 17 and the stop protrusion. When the rack moves forward, one spring is compressed by the transverse stop 17 and bears pressure, while the other spring is not subjected to force. The inertial mass unit consists of a transmission screw 16, a ball nut 15, balls 14, a fixed bearing 12 on the outside of the nut, and a mass flywheel 13, forming a transmission system with a ball screw. The mass flywheel is installed on the outside of the ball nut. When the ball screw is fed in translational motion, the balls drive the ball nut to rotate, which in turn drives the mass flywheel to rotate, while the ball screw does not rotate. The force is borne by the ball screw transmission system. The disk is connected to the gear via a drive shaft. The Halbach permanent magnet array is fixed to the side of the disk, the conductor is fixed to the back iron, and the back iron is fixed to the circular stop 18. The circular stop 18 is fixed to the protective shell 2 by welding, connecting the conductor, the back iron, and the circular stop. There is a certain gap between the Halbach permanent magnet array and the conductor. When the gear is driven by the spring unit or the inertial mass unit, it drives the Halbach permanent magnet array of the disk to rotate through the drive shaft. The conductor cuts the magnetic field lines to generate eddy current force, which hinders the movement of the disk and the gear, thereby reducing the displacement of the structure. Compared with the ordinary arrangement of magnets, the use of the Halbach permanent magnet array can strengthen the magnetic field on one side of the magnet and weaken the magnetic field on the other side.

[0055] One end of the rack 4 is a round rod with a transverse stop 17 welded to it. The spring 3 is placed between the transverse stop 17 and the disc formed by the protrusion of the protective shell. The other end is a rack that meshes with the gear 5, converting the linear motion of the rack into the rotational motion of the gear 5. The rack 4 and the protective shell 2 are connected by a linear bearing 1. When the rack 4 moves in translation, the protective shell 2 does not move with the rack 4.

[0056] One end of the transmission screw 16 is a nut groove, which is connected to the ball nut 15 by using ball 14. The ball 14 and the ball nut 15 convert the linear motion of the transmission screw into rotational motion, and drive the mass flywheel 13 to rotate. The mass flywheel 13 is fixed on the ball nut 15. The other end is a rack that meshes with the gear 5. Similarly, the linear motion of the transmission screw is converted into the rotational motion of the gear 5.

[0057] The gear 5 is connected to the tension spring 3 via the rack 4, and to the ball nut 15 via the transmission screw 16 to drive the mass flywheel 13. The gear 5 is connected to the disk 7 via the transmission shaft 6 to drive the Halbach permanent magnet array fixed on the side of the disk 7 to rotate.

[0058] The conductor 9 is embedded in the back iron 10, and the back iron 10 is embedded in the circular retainer 18. The circular retainer is fixed on the protective shell 2. An air gap cavity 11 is left between the conductor 10 and the Halbach permanent magnet array 8. When the Halbach permanent magnet array 8 rotates with the disk 7, the conductor 9 and the back iron 10 and the circular retainer 18 remain fixed.

[0059] The above description of the embodiments is provided to enable those skilled in the art to understand and use the utility model. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present utility model is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present utility model without departing from its scope should be within the protection scope of the present utility model.

[0060] Figures 1 to 3 This forms the basic structure of the case. Figure 4 This diagram illustrates a replacement structure with a Halbach permanent magnet array to form a negative stiffness component. The replacement structure further reduces the overall displacement of the structure under stress on the foundation structure, which amplifies the acceleration of the structure. The foundation structure is suitable for long-period structures, such as large bridge projects and tall structures. The negative stiffness component has significant advantages in reducing damping requirements and controlling the structure's wind vibration and seismic response.

[0061] The two compression springs are located between the transverse stop 17 and the stop protrusion, respectively. It also includes a negative stiffness assembly, which consists of two sets of Halbach permanent magnet arrays 8. One set of Halbach permanent magnet arrays 8 is located at one end of the rack 4 of the inertial-capacitive mass unit, and the other set is located on the protective shell 2. The two sets of Halbach permanent magnet arrays 8 are arranged in parallel, and their corresponding NN or SS poles exhibit magnetic repulsion.

[0062] like Figure 6 A finite element simulation diagram of one-sixth of the electromagnetic part of the vibration damping device; Figure 7 Schematic diagram of electromagnetic array arrangement. Figure 7 (a) and (b) are illustrations of the standard layout and the Halbach layout, respectively; Figure 8 Schematic diagram of magnetic flux density mode. Figure 8 (a) and (b) show the magnetic flux densities of the simulated ordinary and Halbach arrangements, respectively. From... Figure 8 (a) clearly shows that the magnetic flux density modulus of the ordinary arrangement near the conductor is almost the same as that of the arrangement near the disk. Figure 8 As clearly seen in (b), the magnetic flux density modulus of the Halbach arrangement is larger on the side closer to the conductor than on the side closer to the disk. Furthermore, compared to a standard arrangement, the magnetic flux density modulus of the Halbach arrangement is larger on the side closer to the conductor and smaller on the side closer to the disk. This demonstrates that the Halbach arrangement can enhance the magnetic field on one side and weaken the magnetic field on the other.

[0063] from Figure 9 The damping force comparison chart shows that the damping force generated by the Halbach arrangement is greater than that generated by the ordinary arrangement. The peak indicates that the damping force generated by the Halbach arrangement is nearly 3 times that generated by the ordinary arrangement.

[0064] TECID (Tunable Inertial Eddy Current Damper) replaces the viscous damping in TVMD (Tunable Viscous Mass Damper) with eddy current damping, such as... Figure 10 The figure shows the maximum inter-story drift response obtained when TECID and TVMD are respectively incorporated into a cantilever structure under excitation by 23 seismic waves. The conventional undamped cantilever structure is represented by C-OS, while the energy-dissipating cantilever structures with TVMD and TECID are represented by TVMD-OS and TECID-OS, respectively. C-OS under a large earthquake... The maximum displacement angle reaches 1 / 263, while the corresponding values ​​for TVMD-OS and TECID-OS are... The maximum values ​​correspond to 1 / 500 and 1 / 476 respectively, which are the lower bounds of the statistical values ​​of the maximum inter-story drift angle for the three structures. The maximum values ​​are 1 / 625, 1 / 714, and 1 / 704 respectively, and the upper bound of the statistical value is... The maximum values ​​were 1 / 169, 1 / 357, and 1 / 344, respectively, while the robustness index of inter-story drift angle for the three structures was... The maximum values ​​are 1 / 233, 1 / 666, and 1 / 625, respectively. It is evident that both TVMD-OS and TECID-OS significantly control the displacement response of the structure, but TECID-OS performs slightly better. This further demonstrates that eddy current dampers are more effective than viscous dampers in controlling the structure's displacement.

[0065] exist Figure 11 As can be seen, under the excitation of the El Mayor earthquake, the maximum displacement response of the top layer of C-OS was 0.86m, the maximum displacement response of the top layer of VD-OS was 0.56m, while the maximum displacement responses of the top layers of TVMD-OS and TECID-OS were 0.34m and 0.28m, respectively. It can be seen that TECID further improved the control of structural displacement response under the control of VD and TVMD.

[0066] The innovative features of the Halbach permanent magnet array and negative stiffness component structure are explained below:

[0067] Figure 12 and Figure 13 The Halbach electromagnetic array shown reinforces the magnetic field on each side relative to the other. The arrows point to the N pole, and the end of the arrow indicates the S pole. Figure 11 The Halbach electromagnetic array shown depicts magnets whose N and S poles are mutually attracted. When one magnet moves relative to the other, the Halbach electromagnetic array on both sides will impede the translation. Furthermore, when the opposing N and S poles move to the next opposing N and S pole, they will form N and S poles, generating a repulsive force that also impedes the translation. This is equivalent to a positive stiffness spring, which will hinder movement.

[0068] like Figure 13 The Halbach electromagnetic array shown depicts magnets with repulsive NN or SS poles. When one magnet moves relative to the other, the Halbach electromagnetic array on both sides assists in this translation. Furthermore, as one NN or SS pole moves to the next corresponding NN or SS pole, an NS pole is formed, generating attraction and aiding translation. This is equivalent to a negative stiffness component facilitating movement. The increased travel of the negative stiffness component displaces the left rack 4, which in turn drives the ball drive nut to rotate, further rotating the mass flywheel with greater damping, effectively mitigating large-stroke impacts. The negative stiffness component increases the damping travel to unload large-stroke impacts; the greater the travel displacement, the greater the damping provided.

Claims

1. An electromagnetic vibration damping device employing a Halbach permanent magnet array, characterized in that, Includes a protective shell (2), inside which are installed a spring unit, an electromagnetic damping unit, and an inertial mass unit; the electromagnetic damping unit is located in the middle of the protective shell (2), the inertial mass unit is located on the left side of the protective shell (2), and the spring unit is located on the right side of the protective shell (2); The spring unit includes a rack (4) and a spring (3); the electromagnetic damping unit includes a gear (5), a drive shaft (6) and a Halbach permanent magnet array (8); the inertial-capacitive mass unit includes a rack (4), a ball screw and a mass flywheel; A spring (3) is mounted on the rack (4) of the spring unit. One end of the rack (4) extends out of the protective shell (2), and the other end of the rack (4) meshes with the gear (5) of the electromagnetic damping unit. The gear (5) rotates through the transmission shaft (6). The Halbach permanent magnet array (8) is mounted on the outside of the gear (5). The gear (5) drives the Halbach permanent magnet array (8) to rotate synchronously. The other side of the gear (5) meshes with one end of the rack (4) of the inertial mass unit. The rack (4) is equipped with a ball screw and a mass flywheel. The gear (5) drives the rack (4) of the inertial mass unit and the spring unit to mesh and move synchronously. The other end of the rack (4) of the inertial mass unit extends out of the protective shell (2). The part of the rack (4) of the inertial mass unit and the spring unit that extends out of the protective shell (2) is connected to the device to be damped.

2. The electromagnetic vibration damping device employing a Halbach permanent magnet array according to claim 1, characterized in that: The electromagnetic damping unit includes a gear (5), a drive shaft (6), a disk (7), a Halbach permanent magnet array (8), a conductor (9), a back iron (10), and a circular stop (18). The disk is connected to the gear via the drive shaft. The Halbach permanent magnet array is fixed on the side of the disk. The conductor is fixed on the back iron. The back iron is fixed on the circular stop (18). The circular stop (18) is fixed to the protective shell (2) by welding, connecting the conductor, the back iron, and the circular stop. A gap is reserved between the Halbach permanent magnet array and the conductor. The spring unit includes a rack and a spring; the spring uses two sets of compression springs, with a spring mounted on the rack (4), a transverse stop (17) on the rack (4), and a stop protrusion on the protective shell (2). A spring is set between the transverse stop (17) and the stop protrusion. When the rack moves forward, one spring is compressed by the transverse stop (17) and bears pressure, while the other spring is not subjected to force. The inertial mass unit includes a rack (4), a ball screw, and a mass flywheel; the spring unit includes a linear bearing (1), a spring (3), a rack (4), and a transverse stop (17); the rack (4) is connected to the protective shell (2) through the linear bearing (1), and the transverse stop (17) is welded to the rack; the inertial mass unit is composed of a transmission screw (16), a ball nut (15), balls (14), a fixed bearing (12) on the outside of the nut, and a mass flywheel (13), forming a transmission system with a ball screw; the mass flywheel is installed on the outside of the ball nut, and when the ball screw is fed in translation, it drives the ball nut to rotate through the balls, thereby driving the mass flywheel to rotate, and the ball screw will not rotate; the force is borne by the ball screw transmission system.

3. The electromagnetic vibration damping device employing a Halbach permanent magnet array according to claim 2, characterized in that: The two compression springs are located between the transverse stop (17) and the stop protrusion, respectively.

4. The electromagnetic vibration damping device employing a Halbach permanent magnet array according to claim 3, characterized in that: It also includes a negative stiffness component, which consists of two sets of Halbach permanent magnet arrays (8). One set of Halbach permanent magnet arrays (8) is located at one end of the rack (4) of the inertial-capacitance mass unit, and the other set of Halbach permanent magnet arrays (8) is located on the protective shell (2). The two sets of Halbach permanent magnet arrays (8) are arranged in parallel, and the corresponding NN or SS poles are in a state of magnetic repulsion.

5. The electromagnetic vibration damping device employing a Halbach permanent magnet array according to claim 4, characterized in that: The Halbach permanent magnet array (8) uses neodymium iron boron permanent magnets.

6. The electromagnetic vibration damping device employing a Halbach permanent magnet array according to claim 1, characterized in that: The electromagnetic damping unit has two sets of electromagnetic damping components on its disk (7), Halbach permanent magnet array (8), conductor (9), and back iron (10). The two sets of electromagnetic damping components are located at both ends of the transmission shaft (6), and the gear (5) is located in the middle of the transmission shaft (6).

7. The electromagnetic vibration damping device employing a Halbach permanent magnet array according to claim 6, characterized in that: A gap is provided between the Halbach permanent magnet array (8) and the conductor (9), and the electromagnetic damping component is also provided with a gap. The gaps are connected to form an air gap cavity (11).

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