A lever-type parameter-adjustable universal vibration damping device

Abstract

The present invention relates to the technical field of structural vibration control, and in particular to a lever-type parameter-adjustable universal vibration damping device. It comprises a suspension structure, a vibration damping structure, a support structure and a cylinder. The present invention designs the connecting part of a simple pendulum as a rigid lever. A cylinder with a certain rigidity is provided on the outside to provide a universal fulcrum of the lever, and the vertical position of the fulcrum can be adjusted by adjusting the number of gaskets at the bottom connection of the cylinder. The mass block is designed to be in the shape of a spherical shell with a certain thickness, with a spherical shell-shaped permanent magnet attached to the bottom. During movement, the mass block causes the spherical shell-shaped conductive metal plate below to cut the magnetic flux lines, thereby generating magnetic damping. By adjusting the number of gaskets at the bottom connection of the conductive metal plate, the vertical position of the metal plate can be adjusted, and by changing the magnetic field strength at its position, the magnitude of the eddy current damping can be changed. The operating frequency and damping of the device of the present invention are adjustable, and vibration in any direction can be reduced. It can cope with structural vibrations caused by various complex environments, and effectively improve the structural safety of the vibration damping object.

Description

Technical Field

[0001] The present invention relates to the technical field of structural vibration control, in particular to a lever-type parameter-adjustable universal vibration damping device. Background Art

[0002] With the development of urbanization and social progress, there are more and more high-rise buildings and facilities, and the environmental factors they face are becoming increasingly complex. In particular, the structural vibration problem of high-rise buildings and facilities such as skyscrapers, transmission towers, and wind turbines is prominent, seriously affecting structural safety and even the safety of people and property. High-rise buildings and facilities are often subject to wind-induced vibrations. This type of vibration is characterized by low frequency, random direction, and long excitation time. Currently, installing vibration damping devices on high-rise buildings and facilities is a common way to control structural vibration and improve structural safety. The vibration damping devices that control this type of vibration are mostly dynamic vibration absorption structures, which are divided into traditional suspended pendulum dynamic vibration absorbers, mass-spring dynamic vibration absorbers, and rubber-supported dynamic vibration absorbers.

[0003] (1) Traditional suspended pendulum dynamic vibration absorber. Using the principle of a simple pendulum, a mass block is suspended inside the vibration-damping object, and its vibration frequency is determined by the length of the rope. When the vibration-damping object vibrates, the pendulum automatically deflects to the other side, generating a braking force to reduce the vibration of the vibration-damping object. Traditional suspended pendulum dynamic vibration absorber. The required mass block is too large, occupies a large space, is difficult to apply damping, has a narrow operating frequency range, is difficult to adjust, and has difficulty coping with complex environments.

[0004] (2) Mass-spring dynamic vibration absorber. Two compression springs are used to support the two sides of the mass block inside the box. The mass block can move in the direction of the spring's expansion and contraction. Its vibration frequency is determined by the spring stiffness and the mass of the mass block. When the vibration object vibrates, the mass block moves to the other side at the same frequency, generating a braking force to reduce the vibration of the vibration object. Mass-spring dynamic vibration absorber. It can only control one-way or two-way vibration, and long-term operation will result in high friction loss.

[0005] (3) Rubber-supported dynamic vibration absorber. A rubber block is used to support and connect a mass block on the horizontal plane of the vibration-control object. The vibration frequency during horizontal vibration is determined by the stiffness of the rubber block and the mass of the mass block. The rubber block also provides damping. Similarly, when the vibration-control object vibrates, the mass block moves to the other side at the same frequency, generating a braking force to reduce the vibration of the vibration-control object. Rubber-supported dynamic vibration absorber. Rubber is prone to aging and degradation after long-term operation, and can only support relatively small mass blocks, affecting the vibration control performance. Summary of the Invention

[0006] The purpose of the present invention is to address the problems existing in the background technology and propose a lever-type parameter-adjustable universal vibration damping device that can control vibration in any direction. It does not require a vibration damping device with a large mass block and can effectively reduce the vibration of the structure of the vibration object.

[0007] The technical solution of the present invention is a lever-type parameter-adjustable universal vibration damping device, comprising a suspension structure, a vibration damping structure, a support structure, and a cylinder. The suspension structure comprises a support, a ball bearing, and a rigid connecting rod. The support is fixed to the lower part of the top structure of the vibration damping object. The ball bearing is mounted on the support for universal rotation. The top of the rigid connecting rod is connected to the ball bearing, and the bottom is connected to the vibration damping structure.

[0008] The supporting structure includes supporting ribs, a base, and a bracket; the base is arranged on the bracket; a gasket is arranged between the base and the bracket, the supporting ribs are arranged on the base, and through holes are provided on the base and the bracket, and are connected and fixed using a first bolt and a first nut;

[0009] The vibration damping structure includes a mass block, a magnet, and a conductive metal plate; the mass block and the conductive metal plate are both spherical shells; the mass block is hoisted at the bottom of the rigid connecting rod, and the magnet is installed at the bottom of the mass block; the conductive metal plate is fixed by a base and support ribs; the sphere centers of the mass block, magnet, and conductive metal plate coincide with each other;

[0010] The whole composed of the mass block and the magnet swings in any direction around the ball bearing under the external vibration excitation;

[0011] The top plate of the cylinder is disc-shaped, with a circular tubular connector at its center; a spherical protrusion is provided on the rigid metal rod; the spherical protrusion contacts the circular tubular connector; a cylinder bracket is provided at the bottom of the cylinder, with a gasket provided between the cylinder bracket and the cylinder; threaded holes are provided on the cylinder bracket and the cylinder, and are connected and fixed using a second bolt and a second nut;

[0012] The bracket and the lower end of the cylinder bracket are both buried inside the base of the vibration control object.

[0013] Preferably, the number of the spacers is set in multiples according to the height to be adjusted.

[0014] Preferably, the stacked thickness of the multiple gaskets does not exceed the height of the circular tubular connector.

[0015] Preferably, the magnet is in the shape of a spherical shell.

[0016] Preferably, the magnet is a combination of multiple small flat magnets.

[0017] Preferably, the relative movement between the conductive metal plate and the magnet generates eddy current damping.

[0018] Preferably, the swing of the rigid connecting rod is subject to the reverse restraining force of the top plate of the cylinder.

[0019] Preferably, the contact point between the rigid link and the top plate is a constraint fulcrum.

[0020] Preferably, a vibration sensor is installed at a side position with the same radius as the center of mass of the mass block and the magnet to measure the operating frequency of the vibration control device.

[0021] Compared with the prior art, the present invention has the following beneficial technical effects:

[0022] The present invention combines the dynamic vibration absorption principle and the lever principle, and uses a controllable eddy current damping component to provide damping, thereby improving the design of a traditional simple pendulum device into a vibration control device. The connecting part of the simple pendulum is designed as a rigid lever. A cylinder with a certain rigidity is provided on the outside to provide a universal fulcrum for the lever. The vertical position of the fulcrum can be adjusted by adjusting the number of gaskets at the bottom connection of the cylinder. This is a frequency adjustment method. The mass block is designed to be spherical with a certain thickness, and a spherical permanent magnet is attached to the bottom. During movement, the spherical conductive metal plate below cuts the magnetic flux lines, thereby generating magnetic damping. By adjusting the number of gaskets at the bottom connection of the conductive metal plate, the vertical position of the metal plate can be adjusted, the magnetic field strength at its position can be changed, and the size of the eddy current damping can be changed. This is a damping adjustment method. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A model diagram of the vibration control object and the vibration control device in the present invention;

[0024] Figure 2 It is a top view of the top plate of the present invention;

[0025] Figure 3 The dynamic model of the vibration control object and the vibration control device in the present invention;

[0026] Figure 4 It is a mechanical signal transmission route map in the present invention;

[0027] Figure 5 is the optimal mass ratio μ and natural angular frequency ratio Ω n / ω n and mass ratio μ s The relationship curve diagram;

[0028] Figure 6 The amplitude ratio X1 / U and frequency ratio ω / Ω of the vibration object after the vibration control device is installed n relationship curve diagram.

[0029] Figure numerals: 1. Top structure of the vibration control object; 2. Side wall support of the vibration control object; 3. Base of the vibration control object; 4. Support; 5. Ball bearing; 6. Rigid connecting rod; 7. Mass block; 8. Magnet; 9. Conductive metal plate; 10. Support rib; 11. Base; 12. Bracket; 13. First nut; 14. First bolt; 15. Top plate; 16. Cylinder; 17. Spherical protrusion; 18. Second bolt; 19. Gasket; 20. Second nut; 21. Cylinder bracket. DETAILED DESCRIPTION

[0030] Example 1

[0031] This invention proposes a lever-type, parameter-adjustable, universal vibration damping device. When a building, or the object, is stimulated by environmental factors and vibrates, the top structure 1 and the sidewall supports 2 of the object undergo relative motion relative to the base 3. This relative motion fundamentally affects the overall structural safety. This horizontal vibration of the top structure 1 drives the rigid connecting rod 6, mass 7, and magnet 8 to swing around the ball bearing 5 in a direction opposite to that of the top structure 1, thereby generating a braking force.

[0032] As conductive metal plate 9 cuts through magnetic flux lines, it generates eddy currents within it, dissipating some of the vibration energy of mass 7 and magnet 8 as heat. The eddy currents generated between conductive metal plate 9 and magnet 8 act as damping, preventing excessive swing of mass 7 and magnet 8 and broadening the operating frequency range of the vibration control device.

[0033] In this embodiment, by changing the number of gaskets 19 between the base 11 and the bracket 12, the relative distance between the conductive metal plate 9 and the magnet 8 can be adjusted, thereby changing the size of the eddy current damping between the two; by changing the number of gaskets between the base 11 and the bracket 12, the size of the above-mentioned eddy current damping can be adjusted to adapt to external vibration excitation in different environments.

[0034] The top plate 15 of the cylinder 16 is a component with a certain mass, and the cylinder 16 is a component with a certain horizontal rigidity to limit the swing of the rigid metal connecting rod 6, but it cannot completely limit it. Another intermediate constraint fulcrum is formed on the rigid metal connecting rod 6 by the top plate 15, the cylinder 16 and the spherical protrusion 17. In the absence of this structure, the support 4, the ball bearing 5, the rigid connecting rod 6, the mass block 7 and the magnet 8 are a traditional simple pendulum structure. When the mass of the vibration control object is too large, the mass block 7 and the magnet 8 need to have a larger mass to meet the vibration control requirements. After introducing the above-mentioned intermediate constraint fulcrum, according to the principle of leverage, the purpose of using a smaller mass block to obtain the same vibration control effect can be achieved.

[0035] Similarly, by varying the number of spacers 19 between cylinder 16 and cylinder support 21, the position of the aforementioned swing fulcrum can be adjusted, thereby adjusting the operating frequency of the entire vibration control device to accommodate external vibration excitation in different environments. The operating frequency of this vibration control device can be measured by installing a vibration sensor on the side of the mass block 7 and magnet 8 at the same radius as the center of mass after all components are installed.

[0036] Example 2

[0037] Considering the structural characteristics of high-rise building facilities, after reasonable simplification, Figure 3 The dynamic model of the vibration control object and the vibration control device is shown, and the mechanical signal transmission route diagram of the model is drawn as follows Figure 4As shown. M (kg) is the mass of the top structure of the vibration control object, K (N / m) is the horizontal stiffness of the side wall support of the vibration control object, x1 (m) is the horizontal displacement of M, m (kg) is the mass of the top structure of the cylinder support, k (N / m) is the horizontal stiffness of the side wall of the cylinder support, x2 (m) is the horizontal displacement of m, m p (kg) is the mass of the mass block connected below the connecting rod, c p is the magnitude of the eddy current damping on the mass block, x p (m) is m p where l1(m) is the length of the upper section of the connecting rod at the intermediate restraint fulcrum, l2(m) is the length of the lower section of the connecting rod at the intermediate restraint fulcrum, and f(N) is the excitation force on the top structure of the vibration control object, f = Fsinωt. Let U be the static deformation of the top structure of the vibration control object under the static force F, then U = F / K.

[0038] Write the exciting force as f = Fe jωt , the displacement of M can be expressed as here, is the complex amplitude of x1. Figure 4 , list Used in conjunction with the frequency transfer function between U Expressed in the form of:

[0039]

[0040]

[0041] Introduce the following parameter definitions

[0042] Natural angular frequency of the vibration object, rad / s

[0043] Natural angular frequency of the cylindrical support structure, rad / s

[0044] λ=l2 / l1:leverage ratio

[0045] μ s =m / M: Mass ratio of the cylindrical support structure to the vibration control object

[0046] μ=m p / M: Ratio of the mass of the pendulum to the mass of the object being vibrated

[0047] Damping ratio, (N·s / m)

[0048] Using these parameters, we can rearrange the formula ① and get the amplitude ratio X1 / U as shown in formula ③. 3 item.

[0049]

[0050] in:

[0051]

[0052] Assume that the area of ​​the magnet facing downward is A, the thickness of the metal conductor plate is t, the resistivity is σ, and the magnetic induction intensity at the location of the metal conductor plate is B. The calculation formula for eddy current damping is as follows:

[0053]

[0054] The values ​​of m, k, l1, and l2 can be determined arbitrarily according to the spatial conditions on site of the vibration control object.

[0055] After the above parameters are determined, μ and c p The parameter determination formulas are shown in formula ⑥ and formula ⑦ respectively. Then you can press the c p The numerical values ​​of the eddy current damping components are designed according to formula ⑤. At this point, the design parameters of the device are completed.

[0056]

[0057]

[0058] in:

[0059]

[0060] K0=-2A 2 C 2 ω 10 +(2ABC 2 +6A 2 C)ω 8 -(4A 2 +8ABC)ω 6 +(4AC+2B 2 C+6AB-2BC 2 )ω 4 -(2C 2 -4A-2B 2 )ω 2 +(2B-2C)

[0061] ⑨

[0062] K2=(3A 2 F 2 +C 2 D 2 )ω 8 -(4ABF 2 +4CD 2 )ω 6 +(B2 F 2 +4CDE+3D 2 +2AF 2 -C 2 E 2 )ω4 - (4DE)ω 2 +(E 2 -F 2 )

[0063] ⑩

[0064] K4=-2F 2 D 2 ω 6 +2DEF 2 ω 4

[0065] According to the spatial conditions of the vibration control object, the values ​​of m, k, l1, and l2 are preliminarily specified, then λ, Ω n 、ω n 、μ s According to formula ⑥, when the lever ratio λ = 5, the optimal mass ratio μ and the natural angular frequency ratio Ω are plotted. n / ω n and mass ratio μ s The relationship diagram is as follows Figure 5 shown.

[0066] This diagram is limited to the case where the lever ratio λ = 5. By creating corresponding charts for different lever ratios, you can use these charts to facilitate design and adjust the values ​​of the initially selected parameters m, k, l1, and l2 to meet installation space requirements and cost considerations.

[0067] After the optimal mass ratio value is determined, substitute it into formula ⑦ to obtain the optimal damping value c in the current state. p Then the parameters of each component of eddy current damping can be designed according to formula ⑤ based on this value.

[0068] When λ=5、m / M=0.1、Ω n / ω n =1 / 3, μ=0.0098, the amplitude ratio X1 / U and frequency ratio ω / Ω of the vibration control object are obtained according to formula ③. n The relationship curve is as follows Figure 6 As shown in the figure, it can be seen that the vibration of the object being controlled is greatly suppressed.

[0069] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A lever-type parameter-adjustable universal vibration damping device, comprising a suspension structure, a vibration damping structure, a support structure and a cylinder (16), characterized in that: The suspension structure includes a support (4), a ball bearing (5) and a rigid connecting rod (6); the support (4) is fixed to the lower part of the top structure (1) of the vibration control object; the ball bearing (5) is mounted on the support (4) for universal rotation; the top of the rigid connecting rod (6) is connected to the ball bearing (5), and the bottom is connected to the vibration control structure; The supporting structure comprises a supporting rib (10), a base (11), and a bracket (12); the base (11) is arranged on the bracket (12); a gasket (19) is arranged between the base (11) and the bracket (12), and the supporting rib (10) is arranged on the base (11); through holes are provided on both the base (11) and the bracket (12), and are connected and fixed using a first bolt (14) and a first nut (13); The vibration damping structure includes a mass block (7), a magnet (8) and a conductive metal plate (9); the mass block (7), the magnet (8) and the conductive metal plate (9) are all spherical shell-shaped; the mass block (7) is suspended at the bottom of the rigid connecting rod (6), and the magnet (8) is installed at the bottom of the mass block (7); the conductive metal plate (9) is fixed by a base (11) and a supporting rib (10); the sphere centers of the mass block (7), the magnet (8) and the conductive metal plate (9) coincide with each other; The mass block (7) and the magnet (8) are integrally formed to swing in any direction around the ball bearing (5) under the action of external vibration excitation; The top plate (15) of the cylinder (16) is disc-shaped, and a circular tubular connector is provided at the center thereof; a spherical protrusion (17) is provided on the rigid connecting rod (6); the spherical protrusion (17) contacts the circular tubular connector; a cylinder bracket (21) is provided at the bottom of the cylinder (16), and a gasket (19) is provided between the cylinder bracket (21) and the cylinder (16); the number of gaskets (19) is set according to the height to be adjusted; through holes are provided on the cylinder bracket (21) and the cylinder (16), and are connected and fixed using a second bolt (18) and a second nut (20); the swing of the rigid connecting rod (6) is subject to the reverse constraint force of the top plate (15) of the cylinder (16), and the contact point between the rigid connecting rod (6) and the top plate (15) is the constraint fulcrum; the top plate (15) of the cylinder (16) is a mass of m The cylinder (16) is a member with a horizontal stiffness of k The components are used to limit the swing of the rigid link (6), but they cannot limit it completely; the top structural mass of the vibration control object is M , the horizontal stiffness of the side wall support of the vibration control object is K ; The lower ends of the bracket (12) and the cylinder bracket (21) are both buried inside the vibration control object base (3).

2. The lever-type parameter-adjustable universal vibration damping device according to claim 1, characterized in that: The stacked thickness of the multiple gaskets (19) does not exceed the height of the circular tubular connector.

3. The lever-type parameter-adjustable universal vibration damping device according to claim 1, characterized in that: The relative motion between the conductive metal plate (9) and the magnet (8) generates eddy current damping.

4. The lever-type parameter-adjustable universal vibration damping device according to claim 1, characterized in that: A vibration sensor is installed at a side position with the same radius as the center of mass of the mass block (7) and the magnet (8) to measure the operating frequency of the vibration control device.

Images