1. A water lubrication tail bearing device with high bearing capacity and vibration reduction is characterized by comprising a bearing lining, a bearing bush, a sealing end cover and a damping structure, wherein the bearing lining and a bearing shaft sleeve are of a coaxial cylindrical structure, the inner wall of the bearing lining is matched with a working shaft, and the outer wall of the bearing lining is matched with the bearing bush; the outer wall of the bearing bush is connected with the base; the sealing end cover is annular and coaxially arranged at the end part of the bearing bush, a notch is formed in the inner side wall of the sealing end cover, a sealing oil cavity is formed between the notch and the end face of the bearing bush, and oil is injected into the sealing oil cavity; the damping structure is a gap structure penetrating through two end faces of the bearing bush, and the gap structure is respectively communicated with the sealing oil cavities at two ends; when the vibration is generated, the gap structure is stretched and deformed, and oil in the sealing oil cavity is axially sucked and discharged in the gap structure.

2. The water lubricated tail bearing assembly of claim 1 wherein said gap structure includes at least two annular cuts in the seal end cap, each ring of intermittent cuts having a different diameter; the radial overlapped part of the discontinuous joint-cutting forms a parallel gap structure, and the joint-cutting of the parallel gap structure forms an oil passage; and a through hole with the diameter larger than the width of the cutting seam is arranged on the parallel gap structure and is used as an oil injection hole.

3. The water lubricated tail bearing assembly of claim 2 wherein said parallel gap structure comprises two layers of annular parallel slits, the parallel slits being partially overlapping and partially offset; two short cutting seams are additionally arranged on the overlapped part of the two layers of parallel cutting seams to form an S-shaped spring body, and the two short cutting seams are oil passing channels; when vibration is generated, the S-shaped spring body generates rhythmical stretching deformation under the action of the exciting force, and oil liquid is sucked and discharged in each joint slot along the axial direction.

4. The water lubricated tail bearing device of claim 3 wherein there are two sets of symmetrically disposed S-shaped spring bodies and the sets of S-shaped spring bodies are evenly spaced circumferentially along the end face of the bearing sleeve.

5. The water lubricated tail bearing device of claim 2 wherein said parallel gap structure comprises three layers of annular parallel slits, the overlapping portions of the parallel slits forming a flexible sheet which is subjected to bending deformation under the action of the excitation force during vibration, and oil is sucked and discharged axially through the slits.

6. The water lubricated tail bearing device of claim 2 wherein the parallel gap structure is formed in the bearing sleeve by an electric discharge cutting technique.

7. The water lubricated tail bearing assembly of claim 1 wherein the inner side of the seal end cap is provided with an annular groove, and a seal ring is disposed in the annular groove and is made of a rubber material.

8. The water lubricated tail bearing device of claim 3 wherein the seal end cap is circumferentially spaced apart by a plurality of bolt holes adapted to the fastening screws by which the seal end cap is secured to the end face of the bearing bushing; the bolt holes and the S-shaped spring bodies are alternately arranged at intervals.

9. The water lubricated tail bearing device of claim 1 wherein said notch is a stepped groove, a sealed oil cavity being formed between the stepped groove and the bearing bushing.

Background

The stern bearing is a key component of a propulsion shafting and is used for bearing the weight of a propeller and a transmission shaft. The water lubrication tail bearing is used as a first link for transmitting shafting vibration to a foundation and even a ship body, and the vibration damping performance of the water lubrication tail bearing plays an important role in controlling the shafting vibration. The water lubricated bearing has severe working conditions, and because the interface of the water lubricated bearing is in a mixed lubrication state, local contact friction and abrasion are easy to occur, and abnormal noise and shaft vibration are generated.

The traditional water lubrication tail bearing is composed of a lining and a lining, wherein the lining is made of copper or stainless steel, and the lining is made of polymer composite materials such as rubber (NBR), sialon (Thordon) and Feroform (Feroform). At present, aiming at the problem of vibration reduction of a water lubrication tail bearing, liner structure optimization and material modification are two common optimization methods. In the aspect of optimizing the lining structure, the lubricating performance of the bearing can be improved and the shafting vibration is indirectly reduced by optimizing the geometric parameters of the surface layer of the bushing, the geometric parameters of the water tank or designing the surface structure; the modification of the lining material is to improve the performance of the bearing by adding a small amount of modified elements or components on the basis of the existing lining material. However, the optimization methods are difficult to simultaneously satisfy the improvement of the bearing capacity and the vibration reduction capacity, the main reason is that the bearing inner liner layer simultaneously bears the requirements of the bearing and the vibration reduction functions, but under severe working conditions such as unbalance loading and heavy loading, the soft inner liner layer can generate obvious extrusion deformation, the optimization methods such as inner liner optimization and micro texture are often compacted to greatly weaken the damping effect, and the contradiction of good regulation of the bearing and the vibration reduction is difficult to achieve by simply optimizing the physical properties of the inner liner.

From the viewpoint of vibration isolation, the bearing liner serves as vibration isolation, and it is desirable that the vibration energy transmitted from the shaft to the bearing housing be as small as possible. According to the theory of linear vibration isolation, only when the excitation frequency is greater thanThe system is only operated when the natural frequency of the vibration isolation system is multipliedHas vibration isolation effect. Therefore, the natural frequency of the bearing lining should be minimized without changing the excitation frequency. However, in order to increase the bearing capacity of the bearing, the bearing needs to have a relatively high stiffness, which, however, tends to result in a higher natural frequency. Therefore, the contradiction between high bearing capacity and low natural frequency becomes one of the bottlenecks in the development of the ship water lubrication tail bearing vibration reduction technology.

Disclosure of Invention

The invention aims to provide a water-lubricated tail bearing device with high bearing capacity and vibration reduction aiming at the defects of the prior art, and solves the problem that the high bearing capacity and the low natural frequency of the water-lubricated tail shaft of the prior ship are contradictory.

The technical scheme adopted by the invention is as follows: a water lubrication tail bearing device with high bearing capacity and vibration reduction comprises a bearing lining, a bearing bush, a sealing end cover and a damping structure, wherein the bearing lining and a bearing shaft sleeve are of a coaxial cylindrical structure, the inner wall of the bearing lining is matched with a working shaft, and the outer wall of the bearing lining is matched with the bearing bush; the outer wall of the bearing bush is connected with the base; the sealing end cover is annular and coaxially arranged at the end part of the bearing bush, a notch is formed in the inner side wall of the sealing end cover, a sealing oil cavity is formed between the notch and the end face of the bearing bush, and oil is injected into the sealing oil cavity; the damping structure is a gap structure penetrating through two end faces of the bearing bush, and the gap structure is respectively communicated with the sealing oil cavities at two ends; when the vibration is generated, the gap structure is stretched and deformed, and oil in the sealing oil cavity is axially sucked and discharged in the gap structure.

According to the scheme, the gap structure comprises at least two layers of intermittent cutting seams annularly cut on the bearing bush, and the diameters of the intermittent cutting seams of all rings are different; the radial overlapped part of the discontinuous joint-cutting forms a parallel gap structure, and the joint-cutting of the parallel gap structure forms an oil passage; and a through hole with the diameter larger than the width of the cutting seam is arranged on the parallel gap structure and is used as an oil injection hole.

According to the scheme, the parallel gap structure comprises two layers of annular parallel cutting seams, wherein the parallel cutting seams are partially overlapped and partially staggered; two short cutting seams are additionally arranged on the overlapped part of the two layers of parallel cutting seams to form an S-shaped spring body, and the two short cutting seams are oil passing channels; when vibration is generated, the S-shaped spring body generates rhythmical stretching deformation under the action of the exciting force, and oil liquid is sucked and discharged in each joint slot along the axial direction.

According to the scheme, every two S-shaped spring bodies are symmetrically arranged to form a group, and a plurality of groups of S-shaped spring bodies are evenly distributed at intervals along the circumferential direction of the end face of the bearing bush.

According to the scheme, the parallel gap structure comprises three layers of annular parallel cutting seams, the parts of the parallel cutting seams which are overlapped form elastic sheets, the elastic sheets can generate bending deformation under the action of excitation force when vibration is generated, and oil liquid is sucked and discharged in the cutting seams along the axial direction.

According to the scheme, the parallel gap structure is manufactured on the bearing bush by adopting an electric spark cutting technology.

According to the scheme, the inner side of the sealing end cover is provided with an annular groove, a sealing ring is arranged in the annular groove, and the sealing ring is made of rubber materials.

According to the scheme, a plurality of bolt holes matched with fastening screws are formed in the sealing end cover at intervals in the circumferential direction, and the sealing end cover is fixed on the end face of the bearing bush through the fastening screws; the bolt holes and the S-shaped spring bodies are alternately arranged at intervals. According to the scheme, the notch is a stepped groove, and a sealing oil cavity is formed between the stepped groove and the bearing bush.

The invention has the beneficial effects that:

1. the bearing lining is made of high-rigidity materials, the damping structure is additionally arranged in the bearing lining, when a shafting runs, vibration generated by various factors is transmitted to the bearing, the damping structure can generate rhythmic tensile deformation under the action of exciting force, oil is sucked and discharged in a gap along the axial direction to generate a piston effect, and large damping is generated, so that energy dissipation is formed, the aim of reducing shafting vibration is fulfilled, the contradiction between high bearing capacity and low natural frequency of the existing bearing is effectively solved, and the high bearing capacity of the water lubrication tail bearing can be met while an obvious vibration reduction effect is provided.

2. According to the invention, the damping structures are circumferentially arranged at intervals, and raw materials between the damping structures can provide higher rigidity, namely, the independent design of rigidity and damping is realized on the bearing bush, so that the enough rigidity can be maintained while the large damping is provided.

3. The invention can pertinently select the distribution position and the size of the damping structure according to the actual working condition requirement, improve the working performance of the bearing, meet the requirements of each vibration reduction direction and strength, and is suitable for the bearing design in the occasions with complex working environment and high vibration noise requirement, such as ships and warships.

4. The invention has simple structure, strong bearing capacity and good vibration damping effect.

Drawings

FIG. 1 is a diagram of a kinetic model of the present invention.

Fig. 2 is an assembly schematic of the present invention.

Fig. 3 is a schematic structural diagram of a bearing main body according to the first embodiment.

Fig. 4 is a schematic view of a damping structure according to the first embodiment.

Fig. 5 is a schematic view of a bearing structure of the second embodiment.

Fig. 6 is a schematic view of a damping structure according to a second embodiment.

FIG. 7 is a schematic view of the installation of the end cap of the present invention.

Fig. 8 is a front view of a sealed end cap of the present invention.

In the figure: 1. a working shaft; 2. water film lining stiffness; 3. a bearing; 4. the structural rigidity of the bushing; 5. damping of the water film lining; 6. damping of the bushing structure; 7. a bearing bush; 8. sealing the end cap; 9. a base; 10. a bearing liner; 11. bolt holes; 12. a damping structure; 13. an oil filler hole; 14. a support body; 15. a parallel gap structure; an S-shaped spring body; 17. fastening screws; 18. an elastic sheet; 19. a seal ring; 20. sealing the oil cavity; 21. and (5) fastening the screw.

Detailed Description

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

As shown in fig. 2, the water lubricated tail bearing device with high bearing capacity and vibration reduction comprises a bearing lining 10, a bearing bush 7, a sealing end cover 8 and a damping structure 12, wherein the bearing lining 10 and the bearing bush 7 are of coaxial cylindrical structures, the inner wall of the bearing lining 10 is matched with a working shaft 1, and the outer wall of the bearing lining 10 is matched with the bearing bush 7, preferably fixed in an interference fit manner; the outer wall of the bearing bush 7 is connected with a base 9; the sealing end cover 8 is annular and coaxially arranged at the end part of the bearing bush 7, a notch is formed in the inner side wall of the sealing end cover 8, a sealing oil cavity 20 is formed between the notch and the end face of the bearing bush 7, and oil is injected into the sealing oil cavity 20; the damping structure 12 and the bearing bush 7 are integrated, the damping structure 12 is a gap structure penetrating through two end faces of the bearing bush 7, and the gap structure is respectively communicated with the sealing oil cavities 20 at two ends; when vibration is generated, the gap structure is stretched and deformed, oil in the sealed oil cavity 20 is axially sucked and discharged in the gap structure, and a piston effect is generated, so that energy dissipation is formed, and the purpose of reducing shafting vibration is achieved. In the invention, oil liquid with different viscosities can be filled in the sealed oil cavity 20 according to actual requirements so as to adjust the damping.

Preferably, the bearing bush 7 is made of high-rigidity materials such as carbon steel; the clearance structure comprises at least two layers of intermittent cutting seams which are annularly cut on the bearing bush 7, and the diameters of the intermittent cutting seams of each circle are different; the radial overlapped part of the discontinuous cutting seam forms a parallel gap structure 15, and the cutting seam of the parallel gap structure 15 forms an oil passage; a through hole having a diameter larger than the slit width is opened as the oil filler hole 13 in the parallel gap structure 15. In this embodiment, the parallel gap structure 15 is formed by cutting a slit on the bearing bush 7 by using an electric spark cutting technique.

Preferably, as shown in fig. 7, the inner side of the end cover 8 is provided with an annular groove, and a sealing ring 19 is arranged in the annular groove, and the sealing ring 19 is pressed to perform a sealing function when being matched with the bearing bush 7. In this embodiment, there are two annular grooves, and two sealing rings 19 are correspondingly disposed, where the sealing rings 19 are made of rubber material and are disposed on the inner side and the outer side of the sealing gap 20 to perform a strict sealing function.

Preferably, as shown in fig. 8, a plurality of bolt holes 11 adapted to fastening screws 17 are circumferentially formed in the seal end cover 8 at intervals, and the seal end cover 8 is fixed to the end face of the bearing bush 7 by the fastening screws 17; the bolt holes 11 and the S-shaped spring bodies 16 are alternately arranged at intervals, so that rigidity reduction caused by too close distance between the bolt holes 11 and the oil-containing gaps is prevented.

Preferably, the notch is a stepped groove, a sealed oil cavity 20 is formed between the stepped groove and the bearing bush 7, oil is filled in the sealed oil cavity 20 after oil is injected, and damping is generated during vibration to play a role in vibration reduction. Tests show that the end sealing can significantly influence the damping coefficient of the oil film damping structure 12, the width of the sealing gap 20 is in negative correlation with the damping coefficient, and the depth of the stepped groove is set according to the working condition of the using equipment.

Example one

As shown in fig. 3 and 4, the parallel gap structure 15 includes two layers of annular parallel slits, and the parallel slits are partially overlapped and partially staggered; two short cutting seams are additionally arranged on the overlapped part of the two layers of parallel cutting seams to form an S-shaped spring body 16, and the two short cutting seams are also oil passing channels; when vibration is generated, the S-shaped spring body 16 generates rhythmic stretching deformation under the action of the exciting force, oil is sucked and discharged in each joint slot along the axial direction, and a piston effect is generated, so that energy dissipation is formed, and the purpose of reducing shafting vibration is achieved.

Preferably, every two S-shaped spring bodies 16 are symmetrically arranged to form a group, and a plurality of groups of S-shaped spring bodies 16 are uniformly distributed at intervals along the circumferential direction of the end face of the bearing bush 7. In this embodiment, the S-shaped spring bodies 16 provide greater damping but lower stiffness, while the two S-shaped spring bodies 16 are not machined between them to serve as the support 14 providing greater stiffness.

In the invention, the two S-shaped spring bodies 16 in the same group are symmetrically arranged, so that the damping effect generated by the action of the two S-shaped spring bodies points to the axis. The position and the shape of the S-shaped spring body 16 are limited by three angles a, b and c, wherein the angle a is an included angle between a connecting line of the middle oil hole and the axis and the central line of the S-shaped spring body 16 so as to determine the position of the S-shaped spring body 16; the angle b is an included angle between the end points of the two ends of the S-shaped spring body 16 and a connecting line of the axis so as to determine the shape of the S-shaped spring body 16; the angle c is the angle between the connecting line of the oil filling hole and the axis and the end point of the S-shaped spring body 16 on the same side, and can be used for adjusting the whole length of the gap so as to adjust the oil filling amount. By adjusting the angles of the three angles, the distribution position and the size of the S-shaped spring body 16 can be designed in a targeted manner, and the requirements on vibration reduction effect and rigidity in all directions are met.

Example two

As shown in fig. 5 and 6, the parallel gap structure 15 includes three layers of annular parallel slits, the overlapped portions of the parallel slits form an elastic sheet 18, when vibration occurs, the elastic sheet 18 is bent and deformed under the action of an excitation force, and oil is sucked and discharged in the slits along the axial direction. The middle layer cutting seam is divided into a left section and a right section, and the left section and the right section form a bilaminar elastic sheet 18 which is bilaterally symmetrical with the upper layer cutting seam and the lower layer cutting seam. The remaining features of the damping structure formed by the spring plate 18 are similar to those of the S-shaped spring body 16. This embodiment can provide a large damping force and also has good linearity characteristics under high loads.

In the invention, the damping structure 12 is machined on the bearing bush 7 by using an electric spark cutting technology; the parallel gap structures 15 are distributed along the circumferential direction of the bearing, are provided with oil injection holes 13, and can be filled with oil liquid with different viscosities so as to adjust the damping; the materials between the gaps form an elastic variable structure which acts with the oil film to provide damping to realize vibration reduction. The parallel gap structures 15 can provide large damping but lower rigidity, materials among different groups of gap structures can provide large rigidity as supporting structures, and the position shape can be determined by setting position distribution angles and shape distribution angles so as to meet the requirements on rigidity and damping in different directions.

The water lubrication tail bearing device separates the bearing function from the vibration reduction function, and a damping structure 12 is formed at a cutting seam of the bearing bush 7. The bearing lining 10 as a bearing structure has unchanged structure and material, adopts high-rigidity materials such as copper or stainless steel and the like to provide larger bearing capacity, and retains the tribological properties of the bearing lining 10, including self-lubrication, low friction and wear resistance; the damping structure 12 as a vibration damping structure can provide large damping c2, and has higher rigidity k2 to meet the bearing requirement, so that energy dissipation and vibration damping are realized under the condition of weakening the bearing capacity of the bearing as little as possible, and the high bearing capacity of the bearing can be ensured, and meanwhile, the remarkable vibration damping effect of the bearing can be ensured.

The principle of the dynamic model of the invention is shown in figure 1, and the working shaft 1 has mass m₁The mass of the bearing 3 is m₂. The working shaft 1 and the bearing 3 do not work normallyThe two parts are in direct contact with each other, and a water film is generated between the two parts. The working shaft 1 is contacted with a water film, and the displacement response x generated by the disturbed force F of the working shaft 1₁Is transmitted to the bearing 3 through the water film to generate a displacement response x₂. The water film and bearing lining will produce water film lining stiffness 2 and water film lining damping 5, respectively k₁And c₁Indicating that this part is mainly load bearing; the bearing bush with the damping structure can provide remarkable damping effect while meeting high bearing capacity, namely, the bearing bush with sufficient bush structural rigidity 4 and remarkable bush structural damping 6 are provided, and k is used respectively₂And c₂Is represented by c₂Is relatively large to ensure a significant damping effect, k₂Relatively large to ensure that the bearing capacity is sufficient.

It should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and the present invention is not limited thereto, and although the present invention has been described in detail with reference to the embodiments, it will be apparent to those skilled in the art that modifications can be made to the technical solutions described in the above-mentioned embodiments, or equivalent substitutions of some technical features, but any modifications, equivalents, improvements and the like within the spirit and principle of the present invention shall be included in the protection scope of the present invention.