CN110296146B

CN110296146B - Broadband damping vibration attenuation modularization water lubricated bearing

Info

Publication number: CN110296146B
Application number: CN201910567699.2A
Authority: CN
Inventors: 金勇�; 刘子豪; 刘正林; 欧阳武
Original assignee: Wuhan University of Technology WUT
Current assignee: Wuhan University of Technology WUT
Priority date: 2019-06-27
Filing date: 2019-06-27
Publication date: 2021-03-30
Anticipated expiration: 2039-06-27
Also published as: CN110296146A

Abstract

The invention provides a broadband damping vibration attenuation modular water-lubricated bearing which comprises an outer bushing, an inner bushing and a main shaft, wherein the outer bushing, the inner bushing and the main shaft are sequentially sleeved from outside to inside, the inner bushing comprises a plurality of groups of composite damping strips and a plurality of stop copper strips, the stop copper strips are uniformly arranged on the inner circumferential surface of the outer bushing at intervals along the circumferential direction, and the plurality of groups of composite damping strips are respectively embedded in a gap between two adjacent stop copper strips and are attached to the inner wall of the outer bushing. The invention can achieve broadband damping vibration attenuation, is suitable for vibration control in more frequency domains, has more changeability in modularization, improves the vibration attenuation and noise reduction effects of the bearing under more working conditions, and improves the comfort level of the civil ship and the concealment of the underwater vehicle.

Description

Broadband damping vibration attenuation modularization water lubricated bearing

Technical Field

The invention belongs to the technical field of mechanical bearing structures, and particularly relates to a broadband damping vibration attenuation modular water-lubricated bearing.

Background

The tail bearing of the underwater vehicle has extremely bad working conditions, the response amplitude of the shafting vibration at the position is relatively large, the tail bearing has a key effect on the attenuation capacity of the vibration as the first link element for transmitting the shafting vibration to the base and even the ship body, the acting distance of an enemy passive sonar can be reduced by about 50% when the underwater vehicle reduces the radiation noise by 6-10dB, and the acting distance of the own passive sonar can be improved by about 1 time, so the vibration reduction and noise reduction research of the tail bearing is complete on the vibration theory system of the ship propulsion shafting, and has important significance on improving the silence level and the survival capacity of ships such as the underwater vehicle.

At present, water lubrication tail bearings have made great progress in vibration and noise reduction through modes of improving bearing lubrication conditions through water tank distribution, surface texture and the like, increasing a high polymer damping layer and the like, but the water lubrication tail bearings are mainly reflected in a low-frequency response area, and underwater vehicles often generate high-frequency sound and howling under special working conditions of low speed, heavy load and the like, so that innovative thinking needs to be developed on the premise of keeping the strength and the attenuation capacity of the tail bearings in the low-frequency area, a design scheme of broadband vibration reduction is researched, and a new method and a new technology for vibration and noise reduction of the tail bearings are explored.

In recent years, the porous structure is considered as one of the main methods for improving the broadband vibration damping and noise reduction of the material, and the porous structure has been advanced in the aspects of high-speed railway carriage materials, high-speed concrete pavement, dampers, foam metal materials, aerostatic bearings, oil-lubricated bearings and the like, but the application research on the vibration damping and noise reduction of the water-lubricated tail bearing is very little.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a broadband damping vibration-damping modular water-lubricated bearing to realize broadband vibration-damping and noise reduction aiming at the existing problems.

The technical scheme adopted by the invention for solving the technical problems is as follows: the utility model provides a broadband damping vibration attenuation modularization water lubricated bearing, its characterized in that includes by outer bushing, neck bush and the main shaft of establishing to interior cover in proper order, the neck bush includes compound damping lath of array and several locking copper bars, several locking copper bars install along the even interval of circumference in the inner peripheral surface of neck bush, compound damping lath of array inlays respectively and locates in the space between two adjacent locking copper bars to laminate with the outer bushing inner wall.

According to the scheme, each group of composite damping battens is composed of a plurality of composite damping battens, and the top centers of two adjacent composite damping battens are axially provided with water grooves.

According to the scheme, each composite damping batten is formed by arranging a plurality of damping modules along the axial direction, and the damping modules are adhered to the inner wall of the outer lining.

According to the scheme, the plurality of damping modules are uniformly arranged at intervals, a gap exists between every two adjacent damping modules, and axial through holes are uniformly distributed in the damping modules.

According to the scheme, the plurality of damping modules are installed in an interference fit mode, axial through holes are uniformly distributed in the damping modules, and the axial through holes in the plurality of damping modules correspond to one another to form through holes.

According to the scheme, the plurality of damping modules are installed in an interference fit mode, axial cavities are uniformly distributed in the damping modules, and fluid is injected into the axial cavities.

According to the scheme, the plurality of damping modules are installed in an interference fit mode, the head damping module and the tail damping module are of solid structures, and axial through holes are uniformly distributed in the middle damping module.

According to the scheme, the outer bushing is made of metal, and the inner bushing is made of nitrile rubber.

The invention has the beneficial effects that: the broadband damping vibration attenuation modular water-lubricated bearing is low in maintenance cost, the whole bearing lining is composed of the rubber damping modules, the bearing is damaged in the use process, only the rubber damping modules are required to be replaced, and the whole bearing is not required to be disassembled in maintenance; the combination of the rubber damping modules with different mesh structures is adopted, so that the rubber damping device can be suitable for more working conditions, the rubber damping modules with different mesh structures are arranged at different positions according to the requirements of rigidity, load and the like, and the application range is wide; the damping vibration reduction of the broadband can be achieved, the vibration control device is suitable for vibration control of more frequency domains, the modularization has more changeability, the vibration reduction and noise reduction effects of the bearing under more working conditions are improved, and the comfort level of a civil ship and the concealment of an underwater vehicle are improved.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

FIG. 2 is a schematic structural view of a composite damping slat according to one embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a damping module according to an embodiment of the present invention.

Fig. 4 is a diagram illustrating a damping mechanism of a water lubricated bearing according to an embodiment of the present invention.

Fig. 5 is a diagram illustrating a modal analysis result of the damping module according to an embodiment of the present invention.

FIG. 6 is a graph of the displacement frequency response at the top surface of the damping module in accordance with one embodiment of the present invention.

Fig. 7 is a diagram of a damping mechanism of a general tail bearing.

Fig. 8 is a graph of modal analysis results for a solid damping module.

FIG. 9 is a graph of displacement frequency response at the top surface of a solid damping module.

Wherein: 1-outer lining, 2-inner lining, 3-main shaft, 4-composite damping lath, 5-stop copper bar, 6-water tank, 7-damping module and 8-axial through hole.

Detailed Description

For a better understanding of the present invention, reference is made to the following description taken in conjunction with the accompanying drawings and examples.

As shown in fig. 1-4, a broadband damping vibration attenuation modularization water lubricated bearing comprises an outer bushing 1, an inner bushing 2 and a main shaft 3 which are sequentially sleeved from outside to inside, wherein the inner bushing comprises a plurality of groups of composite damping strips 4 and a plurality of stop strips 5, the plurality of stop strips are uniformly arranged on the inner circumferential surface of the outer bushing at intervals along the circumferential direction, the plurality of groups of composite damping strips are respectively embedded in a gap between two adjacent stop strips and attached to the inner wall of the outer bushing, and the stop strips are arranged to enable the composite damping strips to be tightly attached and fixed. The outer bushing is made of metal, the elastic modulus is 7.08 multiplied by 106Pa, the density is 1240 kg/m3, the Poisson ratio is 0.47, and the inner bushing is made of nitrile rubber, so that the rubber has good oil resistance, water resistance, solvent resistance and high-pressure oil resistance, and has good compressibility, abrasion resistance and elongation.

Each group of composite damping laths consists of a plurality of composite damping laths, and the top centers of two adjacent composite damping laths are provided with a water tank 6 along the axial direction. Each composite damping lath is formed by arranging a plurality of damping modules 7 along the axial direction, and the damping modules are adhered to the inner wall of the outer lining.

Example one

A plurality of damping modules are installed at even intervals, a gap exists between every two adjacent damping modules, axial through holes 8 are uniformly distributed in the damping modules, and the axial through holes in the plurality of damping modules can be in one-to-one correspondence to form through holes or not. When the main shaft rotates at different speeds, vibration and noise with different frequencies can be generated, vibration energy of the vibration is reduced when the vibration radially penetrates through the tail bearing strip, and compared with the strip without the axial through hole, a part of the vibration energy is consumed after the vibration energy enters the axial through hole, so that the vibration energy capable of penetrating through the inner bushing can be further reduced, and the noise can be absorbed to a certain extent to attenuate the vibration (see fig. 4 and 7). The water in the gaps among the damping modules flows when the main shaft rotates to form fluid-solid coupling, and under the action of external excitation, the water also vibrates and rubs with the outer liner and the damping modules, so that the vibration transmission is attenuated by the damping effect enhanced by the fluid-solid coupling action area.

Example two:

the damping modules are installed in an interference fit mode, axial cavities are evenly distributed on the damping modules, fluid such as silicon oil is injected into the axial cavities, when the main shaft rotates, the silicon oil in the holes vibrates under the action of external excitation and rubs with the wall surface, and the transmission of vibration is attenuated by the damping effect enhanced by the fluid-solid coupling action area.

Example three:

the damping modules are installed in an interference fit mode, the head damping module and the tail damping module are of solid structures, axial through holes are uniformly distributed in the middle damping module, water enters the axial through holes, when the main shaft rotates, the water in the holes vibrates under the action of external excitation and rubs with the wall surface, and the damping effect enhanced by the fluid-solid coupling effect area is utilized to damp transmission of vibration.

The axial through holes are arranged in different structures and different in natural frequency, and the damping modules in different arrangement structures can have vibration and noise reduction effects on vibration and noise with different frequencies. Because the gravity of the main shaft can generate unbalance loading, the lower half part mainly bears the load, and therefore in order to meet the rigidity requirement, the lower half part of the bearing is provided with the rubber damping module with smaller meshes. Different mesh structures are selected among the modules, and the different modules have a damping effect on external simple harmonic loads in different frequency domains, so that broadband damping is realized.

The general size parameter of the porous structure is in the mum-nm level, the oil-containing metal bearing can be formed by powder sintering, and the micro-scale porous structure is difficult to be manufactured by a high-molecular water lubrication tail bearing strip material, so that the structure design of the axial through hole of the damping module is 10^-1macro scale on the mm scale.

The smaller the aperture of the axial through hole of the damping module on the water-lubricated bearing is, the smaller the number of the axial through holes is, the less the mass reduction is caused, and the larger the static rigidity of the water-lubricated bearing is. The larger the aperture, the lower the natural frequency, and the lower the vibration displacement amplitude. A section of damping module unit body containing the axial through hole is intercepted from the bottom plate strip to carry out modal analysis and harmonic response simulation analysis, and the simulation results of the unit bodies with or without the axial through hole are compared. Through modal analysis, only modal results within 1000Hz are extracted for analysis, and from the numerical value of the natural frequency, the numerical value of each order frequency is reduced due to the fact that the quality of the structure is reduced by the perforated plate strip, but the difference is small. From the vibration mode, the first order and the second order are orthogonal bending modes, the third order is a torsion mode, the vibration modes of the two slat unit bodies are basically consistent, only the difference exists in the bending modes in the perforation direction, the perforation increases the displacement ratio of the vibration mode vector of the slat structure in height to a certain extent, but in general, the design of the saturated liquid-containing perforated slat does not greatly change the inherent characteristics and dynamic behavior characteristics of the slat, and therefore, the damping enhancement characteristic generated by liquid fluid-solid coupling in the hole can be used for attenuating the response amplitude of external excitation (see fig. 5 and 8). In the harmonic response analysis, a displacement frequency response diagram in the loaded direction (Y direction) of the top surfaces of the two unit bodies is extracted, the response amplitude of the two unit bodies is in a rising mode along with the increase of frequency, but the structural rigidity of the saturated liquid-containing perforated slat unit body is reduced due to the perforations, and the response amplitude of the top surface is relatively higher, which further illustrates the attenuation capacity of the structural design of the saturated liquid-containing perforated slat on the response amplitude, namely, when an excitation source with the same amplitude acts on the slat, the amplitude transmitted by the saturated liquid-containing perforated slat is lower (see fig. 6 and fig. 9).

The above is only a preferred embodiment of the present invention, and certainly, the scope of the present invention should not be limited thereby, and therefore, the present invention is not limited by the scope of the claims.

Claims

1. A broadband damping vibration attenuation modular water-lubricated bearing is characterized by comprising an outer bushing, an inner bushing and a main shaft, wherein the outer bushing, the inner bushing and the main shaft are sequentially sleeved from outside to inside; each group of composite damping laths consists of a plurality of composite damping laths, and the top centers of two adjacent composite damping laths are provided with water grooves along the axial direction; each composite damping batten is formed by arranging a plurality of damping modules along the axial direction, and the damping modules are stuck to the inner wall of the outer lining.

2. The broadband damping vibration attenuation modular water-lubricated bearing as claimed in claim 1, wherein the damping modules are uniformly arranged at intervals, a gap exists between every two adjacent damping modules, and axial through holes are uniformly distributed in the damping modules.

3. The broadband damping vibration-damping modular water-lubricated bearing according to claim 1, wherein the plurality of damping modules are installed in an interference fit manner, axial through holes are uniformly distributed in the damping modules, and the axial through holes in the plurality of damping modules correspond to one another to form through holes.

4. The broadband damping vibration attenuation modular water-lubricated bearing according to claim 1, wherein the damping modules are installed in an interference fit mode, axial cavities are uniformly distributed in the damping modules, and fluid is filled in the axial cavities.

5. The broadband damping vibration attenuation modular water-lubricated bearing as claimed in claim 1, wherein the plurality of damping modules are installed in an interference fit manner, the head and the tail of the damping modules are of a solid structure, and axial through holes are uniformly distributed in the middle damping module.

6. The broadband damping vibration-damping modular water-lubricated bearing according to claim 1, wherein the outer bushing is made of metal, and the inner bushing is made of nitrile rubber.