阅读说明：本技术 一种带有不均匀孔径的强制润滑轴承 (Forced lubrication bearing with uneven aperture ) 是由 曹贻鹏 张润泽 张新玉 张文平 刘晨 杨国栋 明平剑 柳贡民 国杰 赵晓臣 于 2020-05-18 设计创作，主要内容包括：本发明提供的是一种带有不均匀孔径的强制润滑轴承。在轴承本体内部开有总管,轴承本体沿轴向和周向均开有通向轴承本体内表面的加压孔,所有加压孔在轴承本体内部汇聚于总管,总管通过管路连接压力伺服机构,轴承本体沿周向展开则加压孔呈M×N的网格,各加压孔的圆心呈矩阵形式等距规则分布,沿轴向加压孔的孔径不一致、自首向尾呈小-大-小的趋势变化,沿轴向加压孔的孔径一致。该系统在轴系处于低速运转条件时启动,通过加压孔对运转中的轴系下方强制注入加压介质,使由加压孔喷出的加压介质对轴系负荷较大的位置进行托举,保证轴系旋转情况下与轴承之间始终形成液膜,从而改善轴承润滑不良的状态,缓解轴承摩擦磨损。(The invention provides a forced lubrication bearing with uneven pore diameters. The bearing body is internally provided with a header pipe, the bearing body is provided with pressurizing holes leading to the inner surface of the bearing body along the axial direction and the circumferential direction, all the pressurizing holes are converged in the header pipe inside the bearing body, the header pipe is connected with a pressure servo mechanism through a pipeline, the bearing body is expanded along the circumferential direction, the pressurizing holes are in an MXN grid, the circle centers of the pressurizing holes are regularly distributed in a matrix form at equal intervals, the hole diameters of the pressurizing holes along the axial direction are inconsistent, and the pressurizing holes from the head to the tail are in small-large-small trend changes, and the hole diameters of the pressurizing holes along the axial direction are. The system is started when the shafting is in a low-speed running condition, and the pressurized medium is forcibly injected below the running shafting through the pressurized hole, so that the pressurized medium sprayed out of the pressurized hole lifts the position with larger shafting load, and a liquid film is always formed between the shafting and the bearing under the condition of shafting rotation, thereby improving the poor lubrication state of the bearing and relieving the friction and wear of the bearing.)

1. The utility model provides a force-feed lubrication bearing with inhomogeneous aperture, it has house steward, characterized by to open at the inside of bearing body: the bearing body is provided with pressurizing holes leading to the inner surface of the bearing body along the axial direction and the circumferential direction, all the pressurizing holes are gathered in a main pipe inside the bearing body, the main pipe is connected with a pressure servo mechanism through a pipeline, the bearing body is expanded along the circumferential direction, the pressurizing holes are in an MXN grid, the circle centers of the pressurizing holes are regularly distributed in a matrix form at equal intervals, the hole diameters of the pressurizing holes along the axial direction are inconsistent, and the pressurizing holes along the axial direction are changed from head to tail in a small-large-small trend, and the hole diameters of the pressurizing holes along the axial direction are consistent.

2. A force-lubricated bearing with non-uniform bore diameters as defined in claim 1, wherein: the pressure servo mechanism is formed by connecting a pipeline, a pump, a control valve and a control system, the control system is triggered, the control valve is opened and the pump is instructed to work under the condition that the shaft system runs at a low speed, a pressurized medium is injected into the bearing body through the pipeline through a main pipe and is injected into a gap between the shaft and the bearing through a pressurized hole in the inner surface of the bearing.

3. A force-lubricated bearing with non-uniform bore diameters as defined in claim 2, wherein: the variation trend which changes from head to tail in a small-large-small trend is determined by the position of the maximum pressure point, the aperture of the pressurizing hole is maximum at the position of the maximum pressure point of the bearing in the axial direction, the aperture of the pressurizing hole is gradually reduced towards two ends of the bearing by taking the maximum pressure point as a reference, and the variation trend of the aperture meets the linear, quadratic and higher-order polynomial of an axial length coordinate x; in the circumferential direction, the pressurizing holes are arranged at the positions, which are vertically below the bearings and contacted with the shaft system, and the centers of the pressurizing holes are arranged at equal intervals in the circumferential direction until the height of the center of the bearing is reached.

4. A force-lubricated bearing with non-uniform bore diameters as defined in claim 3, wherein: in the axial direction, the largest diameter pressure hole is located at the midpoint of the bearing.

5. A force-lubricated bearing with non-uniform bore diameters as defined in claim 3, wherein: in the axial direction, the largest diameter pressurizing hole is located at a position to the left or right of the midpoint of the bearing.

Technical Field

The invention relates to a radial sliding bearing, in particular to a radial sliding bearing with forced lubrication.

Background

The radial sliding bearing has the advantages of large bearing capacity, good adaptability and the like, is widely applied to rotary components of ships and machinery, and for the application fields, the control of the operation cost and the increase of the service life of the bearing are the primary conditions for selecting the bearing, so that the reduction of the frictional wear of a bearing system is an important index which is preferably considered in the bearing design. Under the rated operation condition of a shaft system, the shaft and the bearing are separated by a layer of liquid film, the friction coefficient is not large due to the shearing action of the liquid film, and the shaft and the bearing which operate in the hydrodynamic pressure lubrication stage have little abrasion and can be almost ignored. However, when the equipment is started and is in a working condition of higher load and lower rotating speed, such as a low-speed sailing stage of a ship, particularly a starting stage of a shafting of the ship, a shaft is in contact with a bearing part or even in direct contact, the bearing is in a mixed lubrication or boundary lubrication state, the friction coefficient of the bearing is very large at the moment, and if the load of the bearing is higher under the condition, the bearing is seriously abraded, which is a problem that a user of the equipment avoids as much as possible and is difficult to avoid. The invention mainly solves the problem of how to avoid the friction of the bearing under the condition of low speed and heavy load and ensure that the bearing runs in a better lubricating state as much as possible.

The current research emphasizes the analysis and control of the bearing lubrication characteristic, and adopts a plurality of methods to control the lubrication characteristic of the radial sliding bearing by means of simulation and test. The current general design concept focuses on two aspects: firstly, research is carried out from the material perspective to improve and enhance the material characteristics, and a wear-resistant and hard new material and the like are adopted; secondly, the structural optimization developed from the bearing structure angle adopts novel bearing structure, such as changing axle bush thickness, axle bush structure, pipe chute bearing, spiral slot type lubricating structure etc..

In the design of a water-lubricated rubber bearing structure published in naval vessel science and technology 2011vol.33, the optimization research on the water-lubricated rubber bearing structure mainly focuses on the research on the influence of the bearing structure on the hydrodynamic lubrication state, such as the structural factors of the cross-sectional shape of a bearing bush, the thickness of the rubber layer of the bearing bush, the arrangement form of the bearing bush and the like, and the result shows that the friction coefficient of the bearing in normal operation can be reduced by reducing the thickness of the rubber layer of the bearing bush and the arrangement form of the arrangement of the bottom of the bearing into a water flowing groove.

In the article of 'dynamic pressure lubrication characteristic and dynamic contact finite element simulation analysis of spiral groove water lubrication rubber alloy bearing' of university of Chongqing, the spiral groove water lubrication rubber bearing is taken as a research object, a dynamic pressure lubrication mechanism is combined, the dynamic pressure characteristic of the bearing is researched, the influence rule of parameters such as rotating speed, eccentricity, transition fillet, spiral angle, groove number and the like on parameters such as liquid film pressure is given, and the method has reference significance for further optimization of the spiral groove water lubrication rubber alloy bearing.

In the patent document entitled "water-lubricated hydrostatic stern bearing for ship" of the university of wuhan theory of technology, a pressure water outlet groove with gradually increasing length is formed on the inner surface of the lower part of a bearing liner, so that high-pressure water flows between the liner and a stern shaft to form a water film and reduce the direct contact area, thereby achieving the purpose of reducing frictional vibration and providing reference for the optimized design of the stern bearing for the ship.

In the above publications, new concepts have been proposed for the bearing structure. However, in practical situations, the contact force distribution of the radial sliding bearing and the shafting should satisfy the reynolds equation, rather than simply increasing or decreasing from head to tail, and the pressure distribution is about distributed in the form of a high-order polynomial of the bearing length x from the maximum bearing position of the bearing to both sides.

Disclosure of Invention

The invention aims to provide a forced lubrication bearing with uneven pore diameters, which can effectively relieve the friction degree of the bearing.

The purpose of the invention is realized as follows:

the bearing body is internally provided with a header pipe, the bearing body is provided with pressurizing holes leading to the inner surface of the bearing body along the axial direction and the circumferential direction, all the pressurizing holes are converged in the header pipe inside the bearing body, the header pipe is connected with a pressure servo mechanism through a pipeline, the bearing body is expanded along the circumferential direction, the pressurizing holes are in an MXN grid, the circle centers of the pressurizing holes are regularly distributed in a matrix form at equal intervals, the hole diameters of the pressurizing holes along the axial direction are inconsistent, and the pressurizing holes from the head to the tail are in small-large-small trend changes, and the hole diameters of the pressurizing holes along the axial direction are.

The present invention may further comprise:

1. the pressure servo mechanism is formed by connecting a pipeline, a pump, a control valve and a control system, the control system is triggered, the control valve is opened and the pump is instructed to work under the condition that the shaft system runs at a low speed, a pressurized medium is injected into the bearing body through the pipeline through a main pipe and is injected into a gap between the shaft and the bearing through a pressurized hole in the inner surface of the bearing.

2. The variation trend which changes from head to tail in a small-large-small trend is determined by the position of the maximum pressure point, the aperture of the pressurizing hole is maximum at the position of the maximum pressure point of the bearing in the axial direction, the aperture of the pressurizing hole is gradually reduced towards two ends of the bearing by taking the maximum pressure point as a reference, and the variation trend of the aperture meets the linear, quadratic and higher-order polynomial of an axial length coordinate x; in the circumferential direction, the pressurizing holes are arranged at the positions, which are vertically below the bearings and contacted with the shaft system, and the centers of the pressurizing holes are arranged at equal intervals in the circumferential direction until the height of the center of the bearing is reached.

3. In the axial direction, the largest diameter pressure hole is located at the midpoint of the bearing.

4. In the axial direction, the largest diameter pressurizing hole is located at a position to the left or right of the midpoint of the bearing.

In order to solve the problems in the prior art, the invention provides a bearing capable of relieving the lubricating state of a radial sliding bearing, which mainly adopts a forced lubricating mode and a corresponding structural design, considers the shape of a lubricating liquid film generated under the low-speed running working condition of a shafting, and provides a pressurizing hole aperture design for effectively relieving the friction degree of the bearing. In order to achieve the purpose of the invention, the characteristics of the bearing rotating speed, the bearing load range and the liquid film pressure distribution are considered, and the guiding idea of the overall scheme of the invention is provided.

Compared with the prior art, the invention has the following beneficial effects:

(1) low friction and wear performance. A porous forced lubrication bearing structure with the diameter of a pressurizing hole basically consistent with the pressure change of a liquid film is provided, so that the bearing structure can still keep effective lubrication under the conditions of low rotating speed and high load, the abrasion of the bearing is reduced, and the service life is prolonged.

(2) Downward compatibility. When the shaft system runs in a fluid dynamic pressure lubrication stage under a rated working condition, the control valve 5-4 can be closed, and the bearing is not different from a conventional bearing. When the rotating speed of the shafting is low, the control valve 5-4 is opened to generate the forced lubrication effect, and meanwhile, the pressurized medium can lift the shafting, so that the state that the load of the bearing is high is relieved.

Drawings

FIG. 1a is a schematic diagram of the change in bore diameter with the point of maximum pressure at the center of the bearing;

FIG. 1b is a cross-sectional view A-A of FIG. 1 a;

FIG. 1C is a cross-sectional view C-C of FIG. 1 a;

FIG. 2a is a schematic diagram of the change in bore diameter when the point of maximum pressure is not at the center of the bearing;

FIG. 2b is a cross-sectional view A-A of FIG. 2 a;

FIG. 2C is a cross-sectional view C-C of FIG. 2 a;

FIG. 3 is a general schematic including a pressure servo;

FIG. 4 is a schematic diagram showing the center position of the shaft hole and the change in the bore diameter when the pressure maximum point is located at the center of the bearing;

FIG. 5 is a schematic diagram showing the center position of the shaft hole and the change in the bore diameter when the pressure maximum point is not located at the center of the bearing;

fig. 6a to 6f are the pressure distributions obtained by model calculations, wherein fig. 6a is the original bearing without bore (Pmax 12.9 Mpa); fig. 6b is a model in the patent document entitled "water lubricated hydrostatic stern bearing for marine vessel" (Pmax 7.65 Mpa); fig. 6c is a model of the present invention with the pressure maximum point at the bearing center (Pmax ═ 3.77 MPa); fig. 6d is the original bearing without the bore (Pmax 38.8 Mpa); fig. 6e is a model in the patent document entitled "water lubricated hydrostatic stern bearing for marine vessel" (Pmax 30.6 Mpa); fig. 6f is a model when the maximum pressure point of the present invention is not at the bearing center (Pmax is 10.65 MPa).

Detailed Description

The invention is described in more detail below by way of example with reference to the accompanying drawings.

The radial sliding bearing in a low-speed heavy-load environment mainly comprises the following two parts: the bearing body is connected with the pressure servo mechanism through a pipeline. The bearing can be used for water lubrication and oil lubrication, the bearing and the pressurizing aperture on the bearing can be scaled according to the actual size of the shafting, the pressure of the pressure servo mechanism is adjusted according to the operation condition of the shafting, and the forced lubrication of the bearing is realized.

With reference to fig. 1a to 1c, 2a to 2c and 3, the bearing body 1 is axially provided with a pressurizing hole 2, circumferentially provided with a pressurizing hole 3, and internally provided with a header pipe 4. The wear area of the shaft 11 and the bearing is mainly the lower surface of the bearing, and thus the pressurizing holes are mainly concentrated in this area. Pressurizing holes are formed in the axial direction and the circumferential direction of the bearing body 1, the pressurizing holes are converged in the main pipe 4 in the bearing body through communicating holes, and the main pipe 4 and the pressurizing holes 2 and 3 in the inner surface of the bearing are guaranteed to be the only inlets and outlets for pressurizing media and the outside. If the bearing is expanded in the circumferential direction, the arrangement of the pressurizing holes approximates an M × N grid.

For the M rows and the N columns of the pressurizing holes 2 and 3, the circle centers of the pressurizing holes are regularly distributed in a matrix form at equal intervals, the aperture of the pressurizing holes is inconsistent, and the pressurizing holes are changed from head to tail in a small-large-small trend. The pressurized medium is divided into pressure holes 2 and 3 which are staggered in the bearing body through a manifold 4, and flows into a gap between the running shaft and the bearing through an opening on the inner surface of the bearing, so that forced lubrication is realized.

The variation trend of the pore diameter of the pressurizing hole in the axial direction depends on the position of the maximum pressure point. Therefore, the positions of the maximum pressure points in the axial direction can be respectively positioned at the middle point, the left side and the right side of the bearing. The circumferential pressurizing holes 3 are arranged at the position below the bearing and contacted with the shaft system, and are arranged along the circumferential direction at equal intervals until the height of the circle center of the bearing on the basis of the position.

The aperture of the axial pressurizing hole 2 is the largest at the position of the maximum pressure point of the bearing, the aperture of the pressurizing hole is gradually reduced towards two ends of the bearing by taking the maximum pressure point as a reference, and the variation trend of the aperture meets linear, quadratic and higher-order polynomials of an axial length coordinate x (the total length of the bearing is L). The bearing diameter is D. The circumferential pressurizing holes 3 are arranged at the positions below the bearing plumb and contacted with the shaft system, and the centers of the pressurizing holes are arranged at equal intervals along the circumferential direction until the height of the center of the bearing is reached.

After the positions of the axial pressurizing hole 2 and the circumferential pressurizing hole 3 are determined, the position of the pressurizing hole with the largest aperture is determined according to the position of the maximum pressure point, as shown by R4, R3, R2 and R1 marked in fig. 1a to 1c and fig. 2a to 2c, that is, the hole spacing is the same and the aperture is different, and the aperture is larger near the region with larger load, that is, R1 is smaller than R2, and R3 is smaller than R4. In fig. 1a to 1c, the pressure hole of the largest diameter in the axial direction is located at the midpoint of the bearing, i.e. the point of maximum pressure is at the center of the bearing. In fig. 2a to 2c, the pressure hole having the largest diameter in the axial direction is located to the left or right of the center point of the bearing, i.e., the pressure maximum point is not located at the center of the bearing.

The areas of maximum pressure and the distribution of the apertures can be arranged according to the positions indicated by the arrows in fig. 4 and 5, in which the trend of the aperture is indicated below the abscissa. Taking a ship axis as an example, because a stern bearing needs to bear the concentrated mass action of a propeller, the maximum pressure point usually appears at a position which is far away from the end part and is deviated from the propeller, and the aperture is adjusted to two sides from the maximum pressure point according to the trend that the aperture is gradually reduced; the maximum pressure point of the middle bearing usually appears at the middle position of the length of the bearing, and the aperture is adjusted to the two sides according to the trend that the aperture is gradually reduced from the maximum pressure point.

The pressure servo mechanism 5 is formed by connecting a pipeline 5-1, a pump 5-2, a control system 5-3 and a control valve 5-4. The rotating speed sensor 10 detects that the shaft system is in a low-speed running condition, triggers the control system 5-3 and opens the control valve 5-4, instructs the pump 5-2 to work, and injects a pressurized medium into the bearing body 1 through the pipeline 5-1 and the manifold 4, so that the pressurized medium is injected into a gap between the shaft and the bearing through a pressurized hole in the inner surface of the bearing. It is possible to make water-lubricated bearings, oil-lubricated bearings or liquid film-lubricated bearings.

In order to verify the effect of the invention, a model in a patent document entitled "water-lubricated hydrostatic stern bearing for ship" is taken as an example, and further effect comparison is performed on a forced lubrication bearing with distributed pores.

As shown in fig. 3, when the rotational speed of the shaft system is reduced, the control system 5-3 is activated, the control valve 5-4 is opened, the pump 5-2 is operated, the line medium is pressurized and maintained at a constant pressure, and the pressurized medium is injected into the bearing body 1 through the manifold 4.

The pressurized medium injected into the bearing main pipe 4 flows out to the inner surface of the bearing along the inner pipelines of the bearing body, namely the axial pressurized hole 2 and the circumferential pressurized hole 3, and the pressurized medium is brought into a gap between the shaft and the bearing through the rotating shaft system, so that the lubricating state of the shaft system is improved.

The aperture change trend of the pressurizing hole inside the bearing depends on the bearing load distribution, and the aperture change trend meets linear, quadratic and higher-order polynomials of an axial length coordinate x (the total length of the bearing is L).

Taking the middle bearing as an example, the position of the bearing load maximum pressure point is located at the middle point of the bearing, so that the control of the maximum aperture is set at the position of the maximum pressure point, as shown in fig. 4. The pressure distribution obtained by the model calculation is shown in fig. 6 a-6 c.

For the embodiment that the maximum pressure point of the bearing is not at the middle point of the bearing, the position of the maximum pressure point is firstly found, and the position meets the requirement

(bearing length L) is a dimensionless lengthwise coordinate whereby the maximum pressure point is setThe aperture, as shown in fig. 5, is plotted on the abscissa of the graph with the trend from left to right as small-large-small. The calculated pressure distribution is shown in fig. 6d to 6 f.

For the traditional bearing result, the model in the patent document entitled "water lubrication hydrostatic stern bearing for ship" can reduce the maximum liquid film pressure by 40%, and the model of the invention can reduce the maximum liquid film pressure by 71%, greatly reduce the liquid film pressure, relieve the bearing friction and have better application effect.