A multi-frequency damped modulation squeeze film damper

Abstract

The present invention discloses a multi-frequency damped modulation squeeze film damper, which comprises a housing, a squeezing member and a plurality of resonators. The squeezing member includes a first squeezing plate, a second squeezing plate arranged from top to bottom in sequence, and a damping liquid squeeze film arranged between the first squeezing plate and the second squeezing plate. An installation cavity is formed on the first squeezing plate. The resonator is connected with a first elastic seal, and the damping liquid squeeze film contacts the first elastic seal. In the present invention, a push rod is fixedly connected to a platform or structure to be vibration-damped and a carrier platform. The relative movement between the first squeezing plate and the second squeezing plate during vibration forms a damping liquid squeeze film. The fluid load of the squeeze film applies a boundary excitation to the resonator. The first squeezing plate and the resonator undergo forced vibration. The multiple resonators distributed on the first squeezing plate will change the amplitude-frequency and phase-frequency characteristics of the first squeezing plate, obtaining multiple resonance frequency points, so as to simultaneously suppress multiple resonance points of the platform or structure to be vibration-damped.

Description

Technical Field

[0001] The present invention relates to the field of ultra-precision vibration damping technology, and particularly to a multi-frequency point damping modulation squeeze film damper. Background Art

[0002] Suppressing resonance amplification has an important impact on the performance of mechanical equipment. The vibration suppression of the peak response at the resonance frequency point requires large damping to achieve. However, for high-frequency vibrations, larger damping will cause the vibration to deteriorate; traditional passive (passive) frequency-variable damping can achieve large damping at low frequencies and small damping at medium and high frequencies, but for the multi-line spectrum vibrations that occur in rotating machinery, small damping at medium and high frequencies cannot achieve effective vibration suppression effects. How to achieve vibration suppression at multiple line spectrum frequency points on the basis of large damping at low frequencies and small damping at high frequencies is a scientific problem that urgently needs to be solved.

[0003] Generally, a damper achieves the damping effect by shearing or squeezing viscous fluid. For Newtonian fluid, the damping coefficient of the damper does not change with the frequency. For a squeeze film damper, the squeeze surface with an elastic base has a specific natural frequency. The elastic base generates forced vibration under the action of the squeeze film fluid load. After reaching the natural frequency, the phase of its vibration will change, increasing the local squeeze amplitude and generating a large damping force. After the squeeze frequency is greater than the natural frequency of the elastic base, the local squeeze amplitude decreases due to the phase change, generating a small damping force. Due to this vibration characteristic of the elastic base, a squeeze film rheological characteristic that changes with frequency is generated. The fluid load of the squeeze film has a strong coupling effect on the natural frequency of its elastic squeeze surface. The stiffness, mass, and damping parameters of the elastic base will all affect its natural frequency and forced vibration characteristics, resulting in changes in the squeeze film rheological characteristics. The rheological characteristics of the squeeze film will in turn change the natural frequency of the elastic base.

[0004] The layout and modal order of the distributed elastic base are the basis for accurately regulating the large damping frequency points. At the same time, its frequency response characteristics need to be considered, including the vibration response amplitude and phase, and the amplitude and phase are affected by the mass and area of the elastic base. However, the current rheological mechanism affected by the elastic base is still unclear.

[0005] For example, a squeeze film type self-tuning vibration absorber with the publication number CN111692257B includes a spring oscillator and a squeeze bottom plate. A liquid film is arranged between the spring oscillator and the squeeze bottom plate. When the spring oscillator vibrates, it squeezes the liquid film to generate a damping force to dissipate the vibration energy. The squeeze surfaces of the spring oscillator and the squeeze bottom plate have superhydrophobic characteristics or surface pore structures to reduce the damping force; however, in this technical solution, only large damping at low frequencies and small damping at medium and high frequencies can be achieved, but for the multi-line spectrum vibrations that occur in rotating machinery, small damping at medium and high frequencies cannot achieve effective vibration suppression effects.

[0006] To solve the above problems, the present invention provides a multi-frequency damping modulation squeeze film damper to solve the problem of poor vibration reduction effect of the conventional squeeze film damper. Summary of the Invention

[0007] The object of the present invention is to provide a multi-frequency damping modulation squeeze film damper to achieve the purpose of improving the vibration effect of the damper.

[0008] To achieve the above object, the present invention provides the following solution:

[0009] A multi-frequency damping modulation squeeze film damper includes a housing, a squeezing member disposed in the housing, and a plurality of harmonic oscillators with adjustable natural frequencies. The squeezing member includes a first squeezing plate, a second squeezing plate arranged from top to bottom, and a damping liquid squeeze film disposed between the first squeezing plate and the second squeezing plate. An installation cavity for installing the harmonic oscillator is formed on the first squeezing plate. The installation cavity is separated from the damping liquid by a first elastic seal disposed at the bottom. The harmonic oscillator is connected to the first elastic seal, and the damping liquid squeeze film contacts the first elastic seal.

[0010] Preferably, the harmonic oscillator includes a column with a bottom end disposed in the installation cavity and a top end extending out of the installation cavity, a first mass block disposed at the bottom end of the column, a second mass block disposed at the top end of the column, and a spring sleeved on the part of the column extending out of the installation cavity. Two ends of the spring respectively abut against the second mass block and the first squeezing plate, and the first mass block is connected to the first elastic seal.

[0011] Preferably, the installation cavity includes a connecting channel and an installation chamber that communicate with each other. The column extends into the installation chamber through the connecting channel, and the first mass block is disposed in the installation chamber.

[0012] Preferably, a first limiting sleeve is disposed in the connecting channel. An inner wall of the first limiting sleeve does not contact an outer wall of the column and is used to ensure vertical movement of the column in the connecting channel.

[0013] Preferably, a second elastic seal is disposed on a circumference of the first squeezing plate, and the second elastic seal abuts against an inner wall of the housing.

[0014] Preferably, the damper further includes a first connecting rod connected to the first squeezing plate and a second connecting rod connected to the second squeezing plate. The first connecting rod and the second connecting rod respectively extend out of the housing through a first through hole and a second through hole and are respectively connected to an object to be shock-absorbed and a load platform.

[0015] Preferably, a connecting portion is disposed on the first squeezing plate, and the first connecting rod is connected to the connecting portion through a positioning pin.

[0016] Preferably, a scissor mechanism and a ball screw are provided between the second connecting rod and the second pressing plate. One end of the scissor mechanism is connected to the second connecting rod, and the other end is connected to the second pressing plate. The ball screw is used to adjust the lifting of the scissor mechanism and extends to the outside of the housing.

[0017] Preferably, a plurality of the harmonic oscillators are uniformly arranged on a circle with the same radius centered on the center of the first pressing plate.

[0018] Preferably, a plurality of elastic limiting elements are provided on the inner top surface of the housing. The distance from the bottom of the elastic limiting element to the first pressing plate is less than the distance from the top end of the column to the inner top surface of the housing.

[0019] The present invention has achieved the following technical effects compared with the prior art:

[0020] 1. In the present invention, the first connecting rod and the second connecting rod are fixedly connected to the platform or structure to be vibration-damped and the carrier platform. The relative movement between the first pressing plate and the second pressing plate during vibration forms a damping liquid extrusion film. The fluid load of the extrusion film applies a boundary excitation to the harmonic oscillator. The first pressing plate and the harmonic oscillator undergo forced vibration. The multiple harmonic oscillators distributed on the first pressing plate will change the amplitude-frequency and phase-frequency characteristics of the first pressing plate, obtaining multiple resonance frequency points, thereby simultaneously suppressing multiple resonance points of the platform or structure to be vibration-damped.

[0021] 2. In the present invention, the harmonic oscillator includes a column with a bottom end disposed in the installation cavity and a top end extending out of the installation cavity, a first mass block disposed at the bottom end of the column, a second mass block disposed at the top end of the column, and a spring sleeved on the part of the column extending out of the installation cavity. The two ends of the spring are respectively abutted against the second mass block and the first pressing plate. The first mass block is connected to the first elastic seal; by adjusting the weights of the first mass block and the second mass block, the natural frequency of the harmonic oscillator is changed, thereby changing the amplitude-frequency and phase-frequency characteristics of the first pressing plate.

[0022] 3. In the present invention, a scissor mechanism and a ball screw are provided between the second connecting rod and the second pressing plate. One end of the scissor mechanism is connected to the second connecting rod, and the other end is connected to the second pressing plate. The ball screw is used to adjust the lifting of the scissor mechanism and extends to the outside of the housing. By adjusting the height of the scissor mechanism through the ball screw, the thickness of the damping liquid extrusion film between the first pressing plate and the second pressing plate is further completed, thereby achieving the control and adjustment of the damping force. Description of the Drawings

[0023] To more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Appendix Figure 1 is the main sectional view of the present invention;

[0025] Appendix Figure 2 is the top view of the present invention;

[0026] Among them, 1, the first connecting rod; 2, the housing; 3, the elastic limiting element; 4, the second elastic sealing element; 5, the first pressing plate; 6, the second pressing plate; 7, the third elastic sealing element; 8, the ball screw; 9, the scissor mechanism; 10, the first elastic sealing element; 11, the second connecting rod; 12, the first mass block; 13, the column; 14, the first limiting sleeve; 15, the second mass block; 16, the positioning pin; 17, the second limiting sleeve. Specific embodiments

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] The purpose of the present invention is to provide a multi-frequency point damping modulation squeeze film damper to achieve the purpose of improving the vibration effect of the damper.

[0029] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0030] Reference Figures 1 to 2, a multi-frequency damped modulation squeeze film damper, comprising a housing 2, a squeezing member disposed within the housing 2, and a plurality of resonators with adjustable natural frequencies. The squeezing member includes a first squeezing plate 5, a second squeezing plate 6 disposed successively from top to bottom, and a damping liquid squeeze film disposed between the first squeezing plate 5 and the second squeezing plate 6. An installation cavity for installing the resonators is formed on the first squeezing plate 5. The installation cavity is separated from the damping liquid by a first elastic seal member disposed at the bottom. The resonator is connected to the first elastic seal member, and the damping liquid squeeze film contacts the first elastic seal member. In the present invention, by fixedly connecting the first link and the second link to the platform or structure to be vibration-damped and the carrier platform, the relative movement between the first squeezing plate 5 and the second squeezing plate 6 during vibration forms a damping liquid squeeze film. The fluid load of the squeeze film applies a boundary excitation to the resonator. The first squeezing plate 5 and the resonator undergo forced vibration. A plurality of resonators distributed on the first squeezing plate 5 will change the amplitude-frequency and phase-frequency characteristics of the first squeezing plate 5, obtaining a plurality of resonance frequency points, thereby simultaneously suppressing a plurality of resonance points of the platform or structure to be vibration-damped.

[0031] Reference Figure 1 , the resonator includes a column 13 with its bottom end disposed within the installation cavity and its top end extending out of the installation cavity, a first mass block 12 disposed at the bottom end of the column 13, a second mass block 15 disposed at the top end of the column 13, and a spring sleeved on the portion of the column 13 extending out of the installation cavity. The two ends of the spring respectively abut against the second mass block 15 and the first squeezing plate 5. The first mass block 12 is connected to the first elastic seal element 10. By adjusting the weights of the first mass block 12 and the second mass block 15, the natural frequency of the resonator is changed, thereby changing the amplitude-frequency and phase-frequency characteristics of the first squeezing plate 5.

[0032] Reference Figure 1 , the installation cavity includes a connecting channel and an installation chamber that are interconnected. The column 13 extends into the installation chamber through the connecting channel, and the first mass block 12 is disposed within the installation chamber.

[0033] Reference Figure 1 , a first limiting sleeve 14 is disposed within the connecting channel. The inner wall of the first limiting sleeve 14 does not contact the outer wall of the column 13 and is used to ensure the vertical movement of the column 13 within the connecting channel.

[0034] Reference Figures 1 to 2 , a second elastic seal member 4 is disposed on the circumference of the first squeezing plate 5. The second elastic seal member abuts against the inner wall of the housing 2.

[0035] Reference Figures 1 to 2, further comprising a first connecting rod 1 connected to the first pressing plate 5 and a second connecting rod 11 connected to the second pressing plate. The first connecting rod 1 and the second connecting rod 11 respectively extend out of the housing 2 through a first through hole and a second through hole and are respectively connected to the object to be shock-absorbed and the load platform.

[0036] Reference Figures 1 to 2 , a connecting portion is provided on the first pressing plate 5, and the first connecting rod 1 is connected to the connecting portion through a positioning pin 16.

[0037] Reference Figure 2 , a scissor mechanism 9 and a ball screw 8 are provided between the second connecting rod and the second pressing plate 6. One end of the scissor mechanism 9 is connected to the second connecting rod, and the other end is connected to the second pressing plate 6. The ball screw 8 is used to adjust the lifting of the scissor mechanism 9 and extends to the outside of the housing 2; by adjusting the height of the scissor mechanism 9 through the ball screw 8, the thickness of the damping liquid extrusion film between the first pressing plate 5 and the second pressing plate 6 is completed, thereby achieving the control and adjustment of the damping force.

[0038] Further, a plurality of resonators are uniformly arranged on a circle with the same radius with the center of the first pressing plate 5 as the center of the circle.

[0039] Reference Figures 1 to 2 , a plurality of elastic limiting elements 3 are provided on the inner top surface of the housing 2, and the distance from the bottom of the elastic limiting element 3 to the first pressing plate 5 is less than the distance from the top of the column to the inner top surface of the housing 2.

[0040] Reference Figure 1 , a second elastic sealing element 4 is provided between the first pressing plate 5 and the housing 2, and a third elastic sealing element 7 is provided between the ball screw 8 and the housing 2.

[0041] Reference Figure 2 , a second limiting sleeve 17 is provided between the first connecting rod and the housing 2.

[0042] Adaptations made according to actual needs are all within the protection scope of the present invention.

[0043] It should be noted that for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. A multi-frequency damping modulation squeeze film damper, characterized in that, It includes a housing, an extrusion member disposed within the housing, and a number of harmonic oscillators with adjustable natural frequencies. The extrusion member includes a first extrusion plate, a second extrusion plate arranged successively from top to bottom, and a damping liquid extrusion film disposed between the first extrusion plate and the second extrusion plate. An installation cavity for installing the harmonic oscillator is formed on the first extrusion plate. The installation cavity is separated from the damping liquid by a first elastic seal disposed at the bottom. The harmonic oscillator is connected to the first elastic seal, and the damping liquid extrusion film contacts the first elastic seal. It further includes a first connecting rod connected to the first extrusion plate and a second connecting rod connected to the second extrusion plate. A scissor mechanism and a ball screw are disposed between the second connecting rod and the second extrusion plate. The harmonic oscillator includes a column with its bottom end disposed within the installation cavity and its top end extending out of the installation cavity, a first mass block disposed at the bottom end of the column, a second mass block disposed at the top end of the column, and a spring sleeved on the part of the column extending out of the installation cavity. The two ends of the spring respectively abut against the second mass block and the first extrusion plate. The first mass block is connected to the first elastic seal.

2. The multi-frequency damping modulation squeeze film damper according to claim 1, characterized in that, The installation cavity includes a connecting channel and an installation chamber that are interconnected. The column extends into the installation chamber through the connecting channel, and the first mass block is disposed within the installation chamber.

3. The multi-frequency damping modulation squeeze film damper according to claim 2, characterized in that, A first limiting sleeve is disposed within the connecting channel. The inner wall of the first limiting sleeve does not contact the outer wall of the column and is used to ensure the vertical movement of the column within the connecting channel.

4. The multi-frequency damping modulation squeeze film damper according to claim 1, characterized in that, A second elastic seal is disposed on the circumference of the first extrusion plate, and the second elastic seal abuts against the inner wall of the housing.

5. The multi-frequency damping modulation squeeze film damper according to claim 1, characterized in that, The first connecting rod and the second connecting rod respectively extend out of the housing through a first through hole and a second through hole and are respectively connected to the object to be shock-absorbed and the load platform.

6. The multi-frequency damping modulation squeeze film damper according to claim 5, characterized in that, A connecting portion is disposed on the first extrusion plate, and the first connecting rod is connected to the connecting portion through a positioning pin.

7. The multi-frequency damping modulation squeeze film damper according to claim 5, characterized in that, One end of the scissor mechanism is connected to the second connecting rod, and the other end is connected to the second extrusion plate. The ball screw is used to adjust the lifting of the scissor mechanism and extends outside the housing.

8. The multi-frequency damping modulation squeeze film damper according to claim 1, characterized in that, A number of the harmonic oscillators are evenly arranged on a circle with the center of the first extrusion plate as the center of the circle and at the same radius.

9. The multi-frequency damping modulation squeeze film damper according to claim 1, characterized in that, A number of elastic limiting elements are disposed on the inner top surface of the housing. The distance from the bottom of the elastic limiting element to the first extrusion plate is less than the distance from the top end of the column to the inner top surface of the housing.

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