Multi-degree-of-freedom dynamic vibration absorber and adjusting method

Abstract

The invention belongs to the technical field of mechanical vibration, and particularly relates to a multi-degree-of-freedom dynamic vibration absorber and an adjusting method. The multi-degree-of-freedom dynamic vibration absorber comprises a connecting bottom plate, a protective cover, a rubber block and a top plate; the connecting bottom plate and the protective cover are detachably connected to form a closed cavity, the bottom surfaces of the rubber blocks are fixed on the surface of the connecting bottom plate in the closed cavity, and the top surfaces of the rubber blocks are connected with the top plate. When the inherent frequency is consistent with the frequency of the controlled structure, the optimal dynamic vibration absorption effect can be achieved.

Description

Technical Field

[0001] The present application belongs to the technical field of mechanical vibration, and in particular relates to a method for adjusting a multi-degree-of-freedom dynamic vibration absorber. Background Art

[0002] Mechanical vibration not only reduces the performance and reliability of the machine itself, but also causes harm to the human body. It is also the cause of noise pollution. Dynamic vibration absorbers are important control devices in the field of vibration control and are widely used in mechanical manufacturing, transportation, aerospace-related structures, equipment vibration reduction and noise reduction devices. Traditional dynamic vibration absorbers can be regarded as a mass-spring-damper system attached to the main system. When the natural frequency of the system is the same as the frequency of the external exciting force, the vibration of the controlled structure can be significantly reduced. However, conventional dynamic vibration absorbers only suppress vibrations in a single direction and cannot perform vibration control of multi-degree-of-freedom structures. Summary of the invention

[0003] In order to solve the above problems, the present application provides a multi-degree-of-freedom dynamic vibration absorber, comprising:

[0004] Connect the bottom plate, protective cover, rubber block and top plate;

[0005] The connecting bottom plate and the protective cover are detachably connected to form a closed cavity. The bottom surface of the rubber block is fixed on the surface of the connecting bottom plate in the closed cavity, and the top surface of the rubber block is connected to the top plate.

[0006] Preferably, the connecting bottom plate and the protective cover are both cubes, and the enclosed cavity is a cube cavity.

[0007] Preferably, the rubber blocks include four pieces, which are respectively fixed at four corners of the connecting bottom plate, and the top plate is provided with limiting bosses at the gaps between adjacent rubber blocks.

[0008] Preferably, there is a reserved gap between the limiting boss and the rubber block.

[0009] Preferably, the four sides of the connection base plate and the protective cover are all provided with mounting edges with through holes, and the bolts pass through the through holes of the connection base plate and the protective cover to be fixedly connected with the vibration-absorbing device.

[0010] Preferably, the connecting bottom plate, the protective cover and the top plate are all made of metal.

[0011] Preferably, there is a reserved gap between the top plate and the connecting bottom plate and the protective cover.

[0012] The two long sides, the two wide sides and the top of the protective cover (4) are all provided with threaded holes, and each threaded hole is provided with an adjustable spring, the adjustable spring comprising a bolt and a spring located at the end of the bolt, and the adjustable spring is installed in the threaded hole through a threaded connection, and the adjustable spring is screwed in so that the spring of the adjustable spring is pressed against the top plate (3), and the screwing amount of the adjustable spring is adjusted to adjust the compression amount of the spring, thereby adjusting the pre-tightening force of the spring on the top plate (3), so that the vibration absorber can adapt to different forms of vibration.

[0013] Preferably, a method for adjusting a multi-degree-of-freedom dynamic vibration absorber is provided, wherein the multi-degree-of-freedom dynamic vibration absorber is used, the vibration absorber is installed on a vibration source, a plurality of sample points with different amplitudes and frequencies are set, and the vibration absorption effect of the vibration absorber on selecting springs adjustable in different directions and the number of springs at each sample point and selecting the precession of the spring is obtained;

[0014] The layout direction, spring stiffness, number of springs and spring precession of the adjustable spring of the vibration absorber with the best vibration control effect on the controlled structure among all sample points are selected; and the layout direction, spring stiffness, number and precession of the adjustable spring of the vibration absorber under different amplitudes and frequencies are obtained by interpolation, and a reference table is made.

[0015] The present application can adapt to various vibration forms by adjusting the spring and has good versatility.

[0016] The advantages of this application include: excessive vibration of mechanical structures will cause fatigue fracture of the structure, reduce the life of the structure, and also cause various structural failures and processing accuracy problems. Dynamic vibration absorber is a commonly used device for suppressing structural vibration, which has the advantages of simple structure and low cost. The present invention realizes multi-degree-of-freedom vibration control by multi-directional deformation of four rubber blocks arranged in the structure. When the natural frequency of the present invention is consistent with the frequency of the controlled structure, the best dynamic vibration absorption effect can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of a multi-degree-of-freedom dynamic vibration absorber according to a preferred embodiment of the present application;

[0018] Figure 2 This is a schematic diagram of a hidden protective cover for a multi-degree-of-freedom dynamic vibration absorber according to a preferred embodiment of the present application;

[0019] Figure 3 It is a schematic diagram of the structure of the multi-degree-of-freedom dynamic vibration absorber with adjustable springs in the present application. DETAILED DESCRIPTION

[0020] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be further described in detail in detail and in detail in conjunction with the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design. In the absence of conflict, the embodiments in the present application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0021] In order to solve the above problems, the present application provides a multi-degree-of-freedom dynamic vibration absorber, such as Figure 1-Figure 3 As shown, including:

[0022] Connect the bottom plate 1, the protective cover 4, the rubber block 2 and the top plate 3;

[0023] The connecting base plate 1 and the protective cover 4 are detachably connected to form a closed cavity, the bottom surface of the rubber block 2 is fixed on the surface of the connecting base plate 1 in the closed cavity, the top surface of the rubber block 2 is connected to the top plate 3, the connecting base plate 1 and the protective cover 4 are all surrounded by mounting edges with through holes, and the bolts pass through the through holes of the connecting base plate 1 and the protective cover 4 to be fixedly connected to the vibration-absorbing device. Install it near the position of the maximum vibration amplitude of the vibration-absorbing device. The protective cover 4 can effectively isolate the influence of the outside world on the main component of the present invention (dynamic vibration absorber), thereby improving the service life and reliability of the dynamic vibration absorber, and the protective cover 4 is connected to the connecting base plate by bolts, which is convenient for disassembly and maintenance; the present invention can be arranged on airborne equipment of aviation structures such as turboprop aircraft and helicopters, which can greatly reduce the vibration response of the controlled structure.

[0024] The rubber block 2 is made of high damping rubber material, and the rubber block 2 is vulcanized and bonded to the connecting bottom plate. The metal top plate 3 has a certain limiting effect on the deformation of the high damping rubber block 2, and the relative movement between the metal top plate 3 and the rubber block 2 can absorb the vibration of the vibration absorbing device.

[0025] The metal top plate 3 is connected to the high-damping rubber block 2 by means of a semi-penetrating screw, so as to limit the position of the rubber block.

[0026] In some optional embodiments, the connecting base plate 1 and the protective cover 4 are both cubes, and the enclosed cavity is a cubic cavity.

[0027] In some optional embodiments, the rubber blocks 2 include four blocks, which are respectively fixed at four corners of the connecting bottom plate 1 , and the top plate 3 is provided with limiting bosses at the gaps between adjacent rubber blocks 2 .

[0028] In some optional implementations, there is a reserved gap between the limiting boss and the rubber block 2 .

[0029] In some optional implementations, the connecting bottom plate 1 , the protective cover 4 and the top plate 3 are all made of metal.

[0030] In some optional embodiments, there are reserved gaps between the top plate 3 and the connecting bottom plate 1 and the protective cover 4 .

[0031] In some optional embodiments, threaded holes are provided on the two long sides, the two wide sides and the top of the protective cover 4, and each threaded hole is provided with an adjustable spring. The adjustable spring includes a bolt and a spring at the end of the bolt. The adjustable spring is installed in the threaded hole through a threaded connection. The adjustable spring is screwed in so that the spring of the adjustable spring is pressed against the top plate 3. The screw-in amount of the adjustable spring is adjusted to adjust the compression amount of the spring, thereby adjusting the pre-tightening force of the spring on the top plate 3, so that the vibration absorber can adapt to different forms of vibration.

[0032] A method for adjusting a multi-degree-of-freedom dynamic vibration absorber, using the multi-degree-of-freedom dynamic vibration absorber, installing the vibration absorber on a vibration source, setting a plurality of sample points with different amplitudes and frequencies, and obtaining the vibration absorption effect of selecting adjustable springs in different directions and the number of springs at each sample point, and selecting the precession of the spring;

[0033] The layout direction, spring stiffness, number of springs and spring precession of the adjustable spring of the vibration absorber with the best vibration control effect on the controlled structure among all sample points are selected; and the layout direction, spring stiffness, number and precession of the adjustable spring of the vibration absorber under different amplitudes and frequencies are obtained by interpolation, and a reference table is made.

[0034] The present application can adapt to various vibration forms by adjusting the spring and has good versatility.

[0035] In the present invention, under the action of external excitation, the top plate 3 causes the rubber block 2 to deform in multiple directions under the action of inertia, including translation, torsion and bending, so that the entire structure can be controlled with multiple degrees of freedom.

[0036] The advantages of this application include: excessive vibration of mechanical structures will cause fatigue fracture of the structure, reduce the life of the structure, and also cause various structural failures and processing accuracy problems. Dynamic vibration absorber is a commonly used device for suppressing structural vibration, which has the advantages of simple structure and low cost. The present invention realizes multi-degree-of-freedom vibration control by multi-directional deformation of four rubber blocks arranged in the structure. When the natural frequency of the present invention is consistent with the frequency of the controlled structure, the best dynamic vibration absorption effect can be achieved.

[0037] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A multi-degree-of-freedom dynamic vibration absorber, characterized in that: include: Connecting the bottom plate (1), the protective cover (4), the rubber block (2) and the top plate (3); The connecting bottom plate (1) and the protective cover (4) are detachably connected to form a closed cavity; the bottom surface of the rubber block (2) is fixed on the surface of the connecting bottom plate (1) in the closed cavity; and the top surface of the rubber block (2) is connected to the top plate (3).

2. The multi-degree-of-freedom dynamic vibration absorber according to claim 1, characterized in that: The connecting bottom plate (1) and the protective cover (4) are both cube-shaped, and the enclosed cavity is a cube-shaped cavity.

3. The multi-degree-of-freedom dynamic vibration absorber according to claim 2, characterized in that: The rubber blocks (2) include four blocks, which are respectively fixed at four corners of the connecting bottom plate (1), and the top plate (3) is provided with limiting bosses at the gaps between adjacent rubber blocks (2).

4. The multi-degree-of-freedom dynamic vibration absorber according to claim 3, characterized in that: A reserved gap is provided between the limiting boss and the rubber block (2).

5. The multi-degree-of-freedom dynamic vibration absorber according to claim 3, characterized in that: The connecting bottom plate (1) and the protective cover (4) are all provided with mounting edges with through holes on all four sides, and bolts are respectively passed through the through holes of the connecting bottom plate (1) and the protective cover (4) to be fixedly connected with the vibration-absorbing device.

6. The multi-degree-of-freedom dynamic vibration absorber according to claim 3, characterized in that: The connecting bottom plate (1), the protective cover (4) and the top plate (3) are all made of metal.

7. The multi-degree-of-freedom dynamic vibration absorber according to claim 3, characterized in that: There is a reserved gap between the top plate (3) and the connecting bottom plate (1) and the protective cover (4).

8. The multi-degree-of-freedom dynamic vibration absorber according to claim 3, characterized in that: The two long sides, the two wide sides and the top of the protective cover (4) are all provided with threaded holes, and each threaded hole is provided with an adjustable spring, the adjustable spring comprising a bolt and a spring located at the end of the bolt, and the adjustable spring is installed in the threaded hole through a threaded connection, and the adjustable spring is screwed in so that the spring of the adjustable spring is pressed against the top plate (3), and the screwing amount of the adjustable spring is adjusted to adjust the compression amount of the spring, thereby adjusting the pre-tightening force of the spring on the top plate (3), so that the vibration absorber can adapt to different forms of vibration.

9. A method for adjusting a multi-degree-of-freedom dynamic vibration absorber, using the multi-degree-of-freedom dynamic vibration absorber as claimed in claim 8, characterized in that: The vibration absorber is installed on the controlled structure, and multiple sample points with different amplitudes and frequencies are set to obtain the vibration absorption effect of selecting adjustable springs in different directions and the number of springs at each sample point, as well as the selected spring screwing amount; The layout direction, spring stiffness, number of springs and spring precession of the adjustable spring of the vibration absorber with the best vibration control effect on the controlled structure among all sample points are selected; and the layout direction, spring stiffness, number and precession of the adjustable spring of the vibration absorber under different amplitudes and frequencies are obtained by interpolation, and a reference table is made.

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