Compound pendulum type rotary inertial eddy current damper

Abstract

The invention discloses a compound pendulum type rotary inertial eddy current damper which comprises a compound pendulum structure, a damping structure, a support structure and an elastic device. The swing rod is arranged in the support structure in a swinging mode, the mass blocks are rotatably arranged on the rotating shaft, and the damping structure comprises a support vortex plate, an end plate, a rotating shaft vortex plate, a permanent magnet and an arc-shaped guide rail. The end plate and the rotating shaft vortex plate are coaxially fixed to the mass block, the permanent magnets are arranged on the two sides of the mass block and the outer side of the end plate in an array mode, the guide rail is arranged on the upper surface of a support bottom plate of the support structure, the side projection of the upper surface of the guide rail is arc-shaped, the vertical projection is a horizontal line segment, and the upper surface of the guide rail is a rough surface. The support vortex plate is arranged on the inner side of the support structure side face. The effective mass and energy consumption density of the damper can be remarkably improved, the vibration control effect is guaranteed, meanwhile, the applicability of the damper in different working environments is improved, the damping adjustment range is widened, and fine classification is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of structural vibration reduction, and more particularly to a compound pendulum type rotating inertia eddy current damper. Background Art

[0002] Engineering structures often suffer from poor structural stability due to high slenderness ratios and low inherent damping. For example, structures such as super-high-rise buildings, towers and piers of extra-large bridges, and the suspenders of long-span arch bridges are prone to significant vibration under loads such as wind and traffic. This can affect user comfort, cause fatigue damage, and even damage to the structure, posing significant challenges to operational safety and achieving its designed service life. Tuned mass dampers (TMDs), due to their efficient single-mode vibration reduction performance, have become the most commonly used method for structural vibration control and are widely used in high-rise buildings and bridge engineering. TMDs primarily utilize two types of energy-dissipating elements: viscous dampers and eddy current dampers. Viscous dampers are prone to leakage under reciprocating loads, have low durability, and are difficult to adjust their damping parameters. Eddy current dampers, however, lack mechanical friction and working fluid, eliminating leakage and sealing issues and offering excellent durability and environmental compatibility.

[0003] Currently, the main structural forms of eddy current damping devices are flat-plate type and rotary type based on ball screw or gear rack. Flat-plate damping devices can provide a low damping coefficient, and their energy consumption capacity often cannot meet the damping force requirements of large-scale engineering structures. Eddy current damping devices that use a ball screw pair transmission system or gear rack to convert the linear motion of the mass block into rotational motion can improve energy consumption efficiency to a certain extent, but their efficiency index is still limited by the lead and overall axial size of the ball screw pair or gear rack. In addition, they have disadvantages such as a small inertia coefficient, easy wear of the transmission mechanism, and low internal space utilization for the same external volume. These disadvantages greatly limit the application and promotion of eddy current damping devices. To this end, pendulum eddy current damping devices came into being and have been developed. For example, the patent application for "Pendulum-Type Eddy Current Tuned Mass Damping Device," with application publication number CN103132628A, discloses a tuned mass damping device that utilizes flexible slings for multi-directional horizontal vibration and eddy current energy dissipation. Vibration control is achieved through an eddy current damping generator installed at the base of the mass, and non-contact energy dissipation improves the damper's stability and durability. However, the flexible slings used to drive the mass's movement make it difficult to control its dynamic stability, failing to meet the damper's stability and durability requirements. Adjusting the damper's frequency by adjusting the sling length results in a narrow adjustable range, making it suitable only for lower frequencies and limiting its application. The patent application publication number CN105138798A, "A Pendulum-type Eddy Current Tuned Mass Damper and Method for Achieving Structural Vibration Reduction", discloses a compound pendulum-type eddy current damper, which achieves damper frequency adjustment by adjusting the distance between the spring and the pendulum rod shaft. However, the damping efficiency of the flat-plate eddy current damping device it uses is much lower than that of the rotary eddy current damping device and the adjustment range is smaller; the effective mass that the fixed pendulum mass block can provide for vibration reduction is relatively low when the working space and mass are the same. Summary of the Invention

[0004] In response to the defects existing in the prior art, the purpose of the present invention is to provide a compound pendulum rotating inertia eddy current damper, which can significantly improve the effective mass and energy consumption density of the damper while maintaining the geometric dimensions, ensure the vibration control effect, and at the same time improve the applicability of the damper in different working environments as well as the range and fine grading of damping adjustment.

[0005] The technical solution adopted by the present invention to solve this technical problem is: a compound pendulum type rotating inertia eddy current damper, including a compound pendulum structure, a damping structure, a bracket structure and an elastic device; The compound pendulum structure includes a pendulum rod, a rotating shaft, and a mass block; the pendulum rod is swingably arranged in the support structure, the lower end of the pendulum rod is connected to the rotating shaft, and the mass block is a disc-shaped structure, and multiple mass blocks are rotatably arranged on the rotating shaft; The damping structure comprises a support vortex plate, an end plate, a rotating shaft vortex plate, permanent magnets and a circular arc guide rail; the end plate and the rotating shaft vortex plate are coaxially fixed with the mass block, the permanent magnets are arranged in an array on the two sides of the mass block and the outer side of the end plate, the guide rail is arranged on the upper surface of the support bottom plate of the support structure, the upper surface side projection of the guide rail is arc-shaped, the vertical projection is a horizontal line segment, the upper surface of the guide rail is a rough surface, and the support vortex plate is arranged on the inner side of the side surface of the support structure. The elastic device is mechanically connected with the swing rod and provides a restoring force for the mass block, so that the static position of the compound pendulum structure is located at the lowest position in the middle of the slide rail; the elastic device is not only a link for mechanical connection in the TMD, but also a core for realizing frequency tuning, energy transfer and dynamic balance; the design of the stiffness parameter of the elastic device is directly related to the vibration reduction performance of the TMD, and the mass of the mass block and the energy dissipation characteristics of the damping element need to be optimized in cooperation to achieve the best vibration reduction effect.

[0006] As a further scheme of the present application, the support structure comprises a support top plate, a support vertical rod and a support bottom plate; the upper and lower ends of the support vertical rod are connected with the support top plate and the support bottom plate respectively to form a frame structure.

[0007] As a further scheme of the present application, the elastic device comprises an elastic element, an elastic element back plate and an elastic element limiting piece. The elastic element back plate is connected with the support vertical rod through a reserved hole and a bolt, the distance of the elastic element back plate relative to the support top plate is adjustable, the elastic element is arranged between the elastic element back plate and the swing rod, the swing rod is provided with the elastic element limiting piece which can adjust the position along the axial direction of the swing rod, and the elastic element limiting piece is used for connecting the elastic element.

[0008] As a further scheme of the present application, the compound pendulum structure further comprises a swing shaft, a swing shaft ear plate, a swing shaft bearing and a bearing cover plate. The swing shaft ear plate is vertically fixed on the lower surface of the support top plate, the swing shaft is connected with the swing shaft ear plate through the swing shaft bearing, and the bearing cover plate is used for limiting the swing shaft bearing from being displaced along the thickness direction of the swing shaft ear plate during work; the swing rod is a rigid rod, and the two ends of the swing rod are connected with the swing shaft and the rotating shaft respectively; the swing rod is vertically arranged with the swing shaft, and the swing shaft and the rotating shaft are arranged in parallel.

[0009] As a further scheme of the present application, a stiffener plate is arranged at the connection position of the swing shaft and the swing rod.

[0010] As a further scheme of the present application, the rotating shaft vortex plate is fixedly connected with the rotating shaft, and the side surface of the rotating shaft vortex plate is parallel to the side surface of the mass block and the distance therebetween is adjustable.

[0011] As a further scheme of the present application, the side surface of the support vortex plate is parallel to the side surface of the end plate and the distance therebetween is adjustable, and the outer side of the end plate is provided with permanent magnets.

[0012] As a further solution of the present invention, the permanent magnets are arranged in a Halbach array on both sides of the mass block and outside the end plate.

[0013] The present invention has at least the following beneficial effects: 1. The disc-shaped mass used in this patent amplifies the equivalent inertial mass through the rotating inertia effect. The composite design of the compound pendulum and rotating inertia significantly improves the inertial mass effect and achieves the "small volume, large inertia" characteristic.

[0014] 2. With the same TMD mass ratio, the integrated compound pendulum and rotating inertial structure are more compact. Eddy current damping offers the advantages of being contactless and fluid-free, operating stably in environments ranging from -40°C to 80°C. The shaft can utilize sealed bearings with an anti-corrosion coating to adapt to high-temperature and smoky environments.

[0015] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an elevation view of the compound pendulum type rotating inertia eddy current damper of the present invention; Figure 2 It is a side view of the compound pendulum type rotating inertia eddy current damper of the present invention.

[0017] Among them, 1-swing shaft ear plate, 2-stiffening plate, 3-swing shaft, 4-swing shaft bearing, 5-elastic element back plate, 6-elastic element, 7-rotating shaft, 8-rotating shaft bearing, 9-mass block, 10-permanent magnet, 11-end plate, 12-bracket eddy current plate, 13-rotating shaft eddy current plate, 14-swing rod, 15-bearing cover plate, 16-bracket top plate, 17-elastic element limiter, 18-guide rail, 19-bracket bottom plate, 20-bracket vertical rod, 21-bolt. DETAILED DESCRIPTION

[0018] The present invention is described in detail and completely below with reference to the accompanying drawings. Those skilled in the art will be able to implement the present invention based on this description. Before describing the present invention with reference to the accompanying drawings, it should be noted that the technical solutions and technical features provided in various parts of the present invention, including those described below, may be combined with each other unless they conflict.

[0019] In addition, the embodiments of the present invention described below are generally only part of the embodiments of the present invention, rather than all of the embodiments. Therefore, based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making any creative efforts should fall within the scope of protection of the present invention.

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific implementation process is as follows: like Figures 1 and 2 As shown, the present invention provides a compound pendulum type rotating inertia eddy current damper, comprising a compound pendulum structure, a damping structure, a support structure and an elastic device; The compound pendulum structure includes a pendulum rod 14, a rotating shaft 7, and a mass 9; the pendulum rod 14 is swingably disposed in a support structure, the lower end of the pendulum rod 14 is connected to the rotating shaft 7, and the mass 9 is a disc-shaped structure. Multiple mass blocks 9 of the same structure are rotatably disposed on the rotating shaft 7. The number of mass blocks 9 is determined according to actual needs. In this embodiment, the mass block 9 is connected to the rotating shaft 7 via a rotating shaft bearing 8. The damping structure includes a support vortex plate 12, an end plate 11, a shaft vortex plate 13, a permanent magnet 10, and an arc-shaped guide rail 18. The end plate 11 and shaft vortex plate 13 are coaxially fixed to the mass 9. The permanent magnets 10 are arranged in an array on both sides of the mass 9 and outside the end plate 11. The guide rail 18 is arranged on the upper surface of the support base plate 19 of the support structure. The side projection of the upper surface of the guide rail 18 is an arc and the elevation projection is a horizontal line segment. The upper surface of the guide rail 18 is a rough surface. The curvature radius R of the arc-shaped guide rail 18 is equal to the sum of the equivalent pendulum length of the compound pendulum and the radius of the disk-shaped mass 9. The mass 9 rolls freely along the arc-shaped track, and its rotation axis is always orthogonal to the tangent direction of the compound pendulum. The support vortex plate 12 is arranged on the inner side of the support structure, that is, the support vortex plate 12 is arranged on the inner side of the support vertical rod 20. The shaft vortex plate 13 and the support vortex plate 12 can be made of aluminum or copper.

[0021] The elastic device is mechanically connected to the pendulum rod and provides a restoring force for the mass block so that the static position of the compound pendulum structure is located at the lowest position in the middle of the slide rail.

[0022] In the above technical solution, when the pendulum 14 swings, the rotating shaft 7 drives the mass 9 (including the permanent magnet 10), the rotating shaft eddy current plate 13, and the end plate 11 (including the permanent magnet 10) to swing together about the axis of the pendulum shaft 3. This swinging causes the mass 9 to roll along the upper surface of the guide rail 18 and the rotating shaft eddy current plate 13 and the end plate 11 to move translationally along the upper surface of the guide rail 18. The permanent magnets 10 embedded in the two side surfaces of the mass 9 rotate relative to the rotating shaft eddy current plate 13, generating a rotational eddy current damping effect (rotational damping device). The permanent magnets 10 on the outer surface of the end plate 11 and the bracket eddy current plate 12 move translationally relative to each other, generating a flat-plate eddy current effect (flat-plate damping device). This achieves a highly efficient and finely adjustable composite eddy current damping system, adding a more efficient rotational damping device while maintaining the functions of the existing flat-plate damping device.

[0023] For conventional engineering applications, the surface roughness of the mass block 9 can be designed to be Ra = 0.4μm (ground), and the surface roughness of the arc-shaped guide rail 18 can be Ra = 0.8μm (lapped), balancing performance and cost. Alternatively, a surface roughness gradient can be applied to the guide rail 18 along the rolling direction of the mass block 9. With the center (lowest position) of the guide rail 18 as the vertical symmetry plane, the center and the 5mm extension to either side have a roughness of Ra = 0.8μm (accelerating the escape from static friction), a roughness of Ra = 0.4μm (stabilizing rolling) from 5mm to 30mm, and a roughness of Ra = 0.6μm (suppressing relative motion) at the 30mm edge of the guide rail 18. The rolling surface roughness of the mass block 9 can be set to 0.2-0.4μm. In this technical solution, the surface roughness gradient design can significantly improve the system's dynamic response speed, motion smoothness, and durability. The rolling surface roughness can significantly optimize the system's friction performance, motion accuracy, and environmental tolerance, making it particularly suitable for engineering applications with stringent requirements for response speed and durability, such as bridges.

[0024] In a preferred embodiment of the present application, the support structure includes: a support top plate 16, a support vertical rod 20, and a support bottom plate 19; the upper and lower ends of the support vertical rod 20 are respectively connected to the support top plate 16 and the support bottom plate 19 to form a frame structure.

[0025] In a preferred embodiment of the present application, the elastic device includes: an elastic element 6, an elastic element back plate 5, and an elastic element limiter 17; The elastic element backplate 5 is connected to the bracket vertical rod 20 via pre-reserved openings and bolts 21. The distance between the elastic element backplate 5 and the bracket top plate 16 is adjustable. A pair of elastic elements 6 are symmetrically positioned between the elastic element backplate 5 and the rocker arm 14, providing restoring force for swinging in both directions, maintaining its resting position at the middle (lowest) position of the slide rail. The rocker arm 14 is equipped with an elastic element stopper 17, which can be adjusted along the axial direction of the rocker arm 14. This stopper 17 is connected to the elastic element 6. By changing this position, the TMD frequency can be finely and continuously adjusted.

[0026] In a preferred embodiment of the present application, the compound pendulum structure further comprises: a pendulum shaft 3, a pendulum shaft ear plate 1, a pendulum shaft bearing 4, and a bearing cover plate 15; The pendulum shaft ear plate 1 is vertically fixed on the lower surface of the bracket top plate 16, the pendulum shaft 3 is connected to the pendulum shaft ear plate 1 through the pendulum shaft bearing 4, and the pendulum rod 14 is driven to rotate by the pendulum shaft 3. The bearing cover plate 15 is used to limit the displacement of the pendulum shaft bearing 4 along the thickness direction of the pendulum shaft ear plate 1 during operation; the pendulum rod 14 is a rigid rod, and the two ends of the pendulum rod 14 are respectively connected to the pendulum shaft 3 and the rotating shaft 7. It can be a fixed connection (such as welding) or a detachable connection (such as bolting) to enhance the adaptability of the component; the pendulum rod 14 is arranged perpendicular to the pendulum shaft 3, and the pendulum shaft 3 and the rotating shaft 7 are arranged parallel.

[0027] In a preferred embodiment of the present application, a stiffening plate 2 is provided at the connection between the rocking shaft 3 and the rocking rod 14 to enhance the fatigue performance of the connection position.

[0028] In a preferred embodiment of the present application, the shaft vortex plate 13 is fixedly connected to the shaft 7 , the side surface of the shaft vortex plate 13 is parallel to the side surface of the mass block 9 , and the distance between the two is adjustable.

[0029] In a preferred embodiment of the present application, the side surface of the bracket vortex plate 12 is parallel to the side surface of the end plate 11 and the distance between them is adjustable. A permanent magnet 10 is provided on the outer side of the end plate 11 (close to the side of the bracket vortex plate 12).

[0030] In a preferred embodiment of the present application, the permanent magnets 10 are arranged in a Halbach array on both sides of the mass block 9 and on the outside of the end plate 11. The Halbach array significantly enhances the magnetic field on one side (such as the side of the end plate 11 and the rotating shaft eddy current plate 13) through the orderly arrangement of the magnet directions, while weakening the magnetic field on the other side (such as the side from the surface of the disc-shaped mass block 9 toward the center), forming a "magnetic monopole" effect, which can greatly reduce the mutual interference of the magnetic fields.

[0031] The disc-shaped mass block 9 used in this application amplifies the equivalent inertial mass through the rotational inertia effect. The combined design of the compound pendulum and the rotational inertia significantly enhances the inertial mass effect, achieving the "small volume, large inertia" characteristic. Parameters can be designed specifically according to requirements.

[0032] In addition, the present application organically integrates the two functions of damping and equivalent mass. The damping is a rotary eddy current damping, and the equivalent mass has a rotational inertia amplification effect. During the swing of the pendulum 14, each disc-shaped mass block 9 rotates on a circular arc track, and drives each disc-shaped mass block 9 to rotate around the rotating shaft 7 at its own center. The rotating shaft eddy current plate 13 is fixed to the rotating shaft 7, that is, the eddy current plate and the permanent magnet 10 fixed on the surface of the disc-shaped mass block 9 have a relative movement, generating a rotary eddy current damping, and the damping power increases with the square of the rotation speed; the bracket eddy current plate 12 and the permanent magnet 10 on the surface of the end plate 11 of the rotating shaft 7 have a relative movement, generating a flat eddy current damping; the overall realization of the joint synergistic energy consumption of swinging and rotation further improves the damping efficiency, especially the dynamic adjustment capability of the rotary eddy current, which can solve the performance degradation problem of traditional dampers under high-frequency vibration. The synergistic energy consumption is as follows: When the pendulum moves, assuming that its swing linear velocity is, for the outermost magnet, when the pendulum moves, the electromagnetic damping force generated by its eddy current circuit is: (1) Where B is the magnetic field strength, the magnet length is a, l is the magnet size (width) in the direction perpendicular to v, the conductor plate thickness is t, ρ is the conductor plate resistivity, and n c is the number of permanent magnets.

[0033] When the single pendulum moves, the electromagnetic wheel rolls, according to the principle of physics, the linear velocity of the electromagnetic wheel rolling is equal to the linear velocity of the single pendulum swinging, then the angular velocity of the rolling wheel swinging can be obtained as: In the formula: v is the single pendulum movement speed, r is the electromagnetic wheel radius.

[0034] Obviously, when the electromagnetic wheel rotates, the electromagnetic damping force generated by the eddy current circuit is calculated according to the same principle and formula (1), then it can be obtained as: (2) Wherein, is the magnetic field strength of the electromagnetic wheel, is the length of the electromagnetic wheel magnet, is the electromagnetic wheel magnet size (length) in the direction perpendicular to v, and the electromagnetic wheel conductor plate thickness , is the resistivity of the electromagnetic wheel conductor plate, is the number of permanent magnets on the electromagnetic wheel.

[0035] During this period, the eddy current plate, permanent magnet 10, shaft 7 and bearing are all part of the effective mass of the TMD, greatly improving the mass ratio of the damper, further improving the damping effect of the damper. The disc type mass block 9 is arranged with permanent magnets 10 on both sides, and each side is arranged with a shaft eddy current plate 13, and the distance between the permanent magnet 10 and the shaft eddy current plate 13 is adjusted to realize adjustable damping, combined with the adjustable number of disc type mass block 9 and shaft eddy current plate 13 in the transverse direction, realizing the fine adjustment of TMD damping ratio.

[0036] Although the embodiments of the present application have been disclosed as above, it is not limited to the application listed in the specification and the embodiments, it can be fully applied to various fields suitable for the present application, and other modifications can be easily realized by those skilled in the art, therefore, the present application is not limited to specific details and the embodiments shown and described herein, without departing from the general concept defined by the claims and the equivalent scope.

Claims

1. A compound pendulum rotating inertia eddy current damper, characterized in that: It includes a compound pendulum structure, a damping structure, a support structure and an elastic device; The compound pendulum structure includes a pendulum rod, a rotating shaft, and a mass block; the pendulum rod is swingably arranged in the support structure, the lower end of the pendulum rod is connected to the rotating shaft, and the mass block is a disc-shaped structure, and multiple mass blocks are rotatably arranged on the rotating shaft; The damping structure includes: a bracket eddy current plate, an end plate, a rotating shaft eddy current plate, a permanent magnet, and an arc-shaped guide rail; the end plate and the rotating shaft eddy current plate are coaxially fixed to the mass block, the permanent magnets are arranged in an array on both sides of the mass block and on the outside of the end plate, the guide rail is provided on the upper surface of the bracket bottom plate of the bracket structure, the side projection of the upper surface of the guide rail is an arc, the vertical projection is a horizontal line segment, the upper surface of the guide rail is a rough surface, and the bracket eddy current plate is provided on the inner side of the side of the bracket structure; The elastic device is mechanically connected to the pendulum rod and provides a restoring force for the mass block so that the static position of the compound pendulum structure is located at the lowest position in the middle of the slide rail.

2. The compound pendulum rotating inertia eddy current damper according to claim 1, characterized in that: The support structure includes: a support top plate, a support vertical rod, and a support bottom plate; the upper and lower ends of the support vertical rod are respectively connected to the support top plate and the support bottom plate to form a frame structure.

3. The compound pendulum rotating inertia eddy current damper according to claim 2, characterized in that: The elastic device includes: an elastic element, an elastic element back plate, and an elastic element limiter; The back plate of the elastic element is connected to the vertical rod of the bracket through reserved openings and bolts. The distance between the back plate of the elastic element and the top plate of the bracket is adjustable. The elastic element is arranged between the back plate of the elastic element and the rocker arm. The rocker arm is provided with an elastic element limiter that can adjust the position along the axial direction of the rocker arm. The elastic element limiter is used to connect the elastic element.

4. The compound pendulum rotating inertia eddy current damper according to claim 3, characterized in that: The compound pendulum structure further includes: a pendulum shaft, a pendulum shaft ear plate, a pendulum shaft bearing, and a bearing cover plate; The pendulum shaft ear plate is vertically fixed on the lower surface of the bracket top plate, the pendulum shaft is connected to the pendulum shaft ear plate through the pendulum shaft bearing, and the bearing cover plate is used to limit the displacement of the pendulum shaft bearing along the thickness direction of the pendulum shaft ear plate during operation; the pendulum rod is a rigid rod, and the two ends of the pendulum rod are respectively connected to the pendulum shaft and the rotating shaft; the pendulum rod is set perpendicular to the pendulum shaft, and the pendulum shaft and the rotating shaft are set parallel.

5. The compound pendulum rotating inertia eddy current damper according to claim 4, characterized in that: A stiffening plate is provided at the connection between the pendulum shaft and the pendulum rod.

6. The compound pendulum rotating inertia eddy current damper according to claim 1, characterized in that: The rotating shaft vortex plate is fixedly connected to the rotating shaft, the side surface of the rotating shaft vortex plate is parallel to the side surface of the mass block, and the distance between the two is adjustable.

7. The compound pendulum rotating inertia eddy current damper according to claim 1 or 6, characterized in that: The side surface of the bracket eddy current plate is parallel to the side surface of the end plate and the distance between the two is adjustable. A permanent magnet is arranged on the outer side of the end plate.

8. The compound pendulum rotating inertia eddy current damper according to claim 1, characterized in that: The permanent magnets are arranged in a Halbach array on both sides of the mass block and outside the end plate.

Images