CN212615886U

CN212615886U - Sliding bearing assembly

Info

Publication number: CN212615886U
Application number: CN202021018149.XU
Authority: CN
Inventors: 张国强; 倪志伟; 范建明; 龚颖
Original assignee: COB PRECISION PARTS Inc
Current assignee: COB PRECISION PARTS Inc
Priority date: 2020-06-05
Filing date: 2020-06-05
Publication date: 2021-02-26
Anticipated expiration: 2030-06-05

Abstract

The utility model relates to a slide bearing assembly, it includes radial slide bearing and bearing frame. Wherein the journal bearing is of a cylindrical configuration having an inner cavity for supporting the drive shaft, the journal bearing having a plurality of first oil holes extending in a wall thickness direction thereof. The bearing housing is configured to hold the radial sliding bearing. Wherein the wall thickness of the journal bearing is gradually reduced from a central position toward both ends of the journal bearing in the longitudinal direction of the journal bearing. According to the utility model discloses a sliding bearing assembly can be so that the transmission shaft under operating condition and radial slide bearing between establish the oil film layer, sliding bearing assembly can be applicable to aerogenerator.

Description

Sliding bearing assembly

Technical Field

The utility model relates to a supporting component of transmission shaft specifically relates to a slide bearing assembly, and it is particularly useful for the application of working under the difficult condition and the environment of high load.

Background

Compared with the traditional energy industry, the wind driven generator generates electricity by utilizing natural wind, so that the wind driven generator has the characteristics of cleanness and environmental protection. As shown in fig. 1, the wind power generator has a support column 1, a nacelle 2, blades 3, and a transmission power generation system. Disposed within the nacelle 2 is a drive-by-wire power generation system that includes a drive shaft 30 extending from one end of the nacelle 2. The end of the drive shaft 30 extending from the nacelle 2 is fixed with blades 3, such as 3 or 2 blades, and the other end is located in a gearbox 4 in the nacelle 2. The nacelle 2 is rotatably fixed to the support column 1, thereby ensuring that the blades 3 are facing the incoming flow. Further, the control system can control the blades 3 to rotate about the longitudinal axis, so as to improve the wind power generation efficiency.

In order to increase the frontal area, the blades 3 of modern wind generators usually have a length of tens of meters, even tens of meters, and therefore have a heavy weight. The weight of the blade 3 is borne by one end of the drive shaft, and thus the load borne by the bearing for supporting the drive shaft is large. In addition, the bearing is stressed further because the wind direction and the wind force of the wind in the natural environment change constantly.

Based on the above situation, the transmission shaft of the existing wind driven generator mostly adopts a rolling bearing. For example, document CN209146153U proposes an improved rolling bearing structure for wind power. Document CN105220062A proposes a wind turbine bearing with special components and special technology. The bearing of this document enables the service life of the wind turbine to be increased. However, the rolling bearings of the above documents and other prior arts are mainly made of alloy steels such as ZGCr15 and ZGCr15SiMn, and have complicated structures, and the manufacturing process of the rolling bearings is complicated. In addition, the large rolling bearing has the characteristics of high manufacturing cost and high subsequent maintenance and replacement cost.

In other mechanical devices, the drive shaft may also be supported by a sliding bearing. Because the blades 3 of the wind driven generator are influenced by wind power and wind with changeable wind directions, the transmission shaft needs to bear the influence of acting force with alternating magnitude and direction, and the conventional sliding bearing cannot be directly applied to the wind driven generator.

SUMMERY OF THE UTILITY MODEL

To the above-mentioned defect of the bearing of aerogenerator transmission shaft according to prior art, the utility model aims to provide a can resist alternating stress environment, be applicable to the slide bearing subassembly of aerogenerator transmission shaft.

This object is achieved by a sliding bearing assembly according to the present invention. The plain bearing assembly includes a radial plain bearing and a bearing housing. Wherein the journal bearing is of a cylindrical configuration having an inner cavity for supporting the drive shaft, the journal bearing having a plurality of first oil holes extending in a wall thickness direction thereof. The bearing housing is configured to hold the radial sliding bearing. Wherein the wall thickness of the journal bearing is gradually reduced from a central position toward both ends of the journal bearing in the longitudinal direction of the journal bearing.

In the case of a radial sliding bearing whose wall thickness extends in the direction of the length of the radial sliding bearing, the inner wall of the radial sliding bearing does not completely contact the drive shaft, at least in the case of a rotation of the drive shaft. Under the condition that lubricating oil is injected from the outside through the oil hole of the radial sliding bearing, the lubricating oil with certain pressure is extruded by the transmission shaft, and the pressure is further increased. The high-pressure lubricating oil flows to a gap formed by the inner wall surface of the radial sliding bearing and the outer surface of the transmission shaft, and under the vibration and rotation action of the transmission shaft, the high-pressure lubricating oil generates partial speed in the radial direction and the axial direction of the transmission shaft, and the high-pressure lubricating oil starts to flow towards all directions and supports the transmission shaft from the inner wall surface of the radial sliding bearing. At the moment, the transmission shaft in a suspended state can obtain a good lubricating effect; the radial sliding bearing spaced apart from the drive shaft is subjected to a smaller frictional force.

According to a preferred embodiment of the invention, the journal bearing is configured such that its outer diameter is gradually reduced from the axial center towards both ends of the journal bearing so as to remain at least partially out of contact between the outer wall surface of the journal bearing and the opposite inner surface of the bearing seat.

According to a preferred embodiment of the present invention, the journal bearing is configured such that the inner diameter thereof gradually increases from the axial center toward both ends of the journal bearing, so that the outer wall surface of the transmission shaft and the opposite inner surface of the journal bearing are at least partially out of contact.

Under the condition that the inner wall surface and the outer wall surface of the radial sliding bearing are both set to be irregular cylinders, the inner wall surface and the outer wall surface of the radial sliding bearing can generate oil film layers. The journal bearing can also be disengaged from the bearing seat, and in the case of a high-speed rotation of the drive shaft, the journal bearing can be rotated synchronously at a low speed, which leads to a further reduction in the friction to which the drive shaft is subjected.

According to a preferred embodiment of the present invention, the radial sliding bearing satisfies: 10^-1≥(D₀-D_x) /(2X X) ≧ 0, where D₀Is the outer diameter of the journal bearing at the axial center position, D_xIs the outer diameter of the radial sliding bearing at a position at a distance X from the axial center.

According to a preferred embodiment of the present invention, the radial sliding bearing satisfies: 10^-1≥(d_x-d₀) /(2X X) ≧ 0, where d₀Is the inner diameter of the radial sliding bearing at the axially central position, d_xIs the inner diameter of the radial sliding bearing at a position at a distance X from the axial center.

According to a preferred embodiment of the invention, the radial slide bearing has an outer wall surface and/or an inner wall surface in a longitudinal section of the radial slide bearing which is of arcuate configuration.

According to a preferred embodiment of the invention, the radial slide bearing has a longitudinal section in which the outer wall surface and/or the inner wall surface of the radial slide bearing is of conical configuration.

According to a preferred embodiment of the present invention, at least a part of the inner wall surface and/or the outer wall surface of the radial sliding bearing is a cylindrical surface, and the cylindrical surface satisfies: l is more than or equal to 70% L and more than or equal to 20% L, wherein L is the axial length of the radial sliding bearing; l is the axial extension of the cylindrical surface.

According to a preferred embodiment of the present invention, the diameter d of the first oil hole is: d is more than or equal to 25mm and more than or equal to 1 mm.

According to a preferred embodiment of the present invention, a total area S1 of cross sections of the plurality of first oil holes and a total area S of the outer wall surface of the journal bearing satisfy: 10% S is greater than or equal to S1.

According to a preferred embodiment of the present invention, the radial sliding bearing is characterized in that the inner wall surface and/or the outer wall surface has at least one annular oil groove communicating with the first oil hole.

According to a preferred embodiment of the present invention, the plain bearing assembly further comprises a thrust bearing sheet in an annular configuration, wherein the thrust bearing sheet can be mounted on at least one end of the plain journal bearing in the axial direction.

According to a preferred embodiment of the present invention, the thrust bearing sheet includes at least one second oil hole extending in a wall thickness direction thereof.

According to a preferred embodiment of the present invention, the thickness of the thrust bearing sheet is reduced gradually from the inner ring position to the outer ring position of the thrust bearing, and the inner diameter of the thrust bearing sheet is equal to the inner diameter of the journal bearing of one end of the journal bearing.

According to a preferred embodiment of the present invention, the first end face of the thrust bearing piece facing away from the journal bearing is a plane perpendicular to the axial direction thereof.

According to a preferred embodiment of the invention, the second end face of the journal bearing is provided with at least one oil reservoir extending in the radial direction of the journal bearing.

According to a preferred embodiment of the invention, the inner wall surface and/or the outer wall surface of the radial sliding bearing is provided with a lubricating layer consisting of a binder and a modifying additive.

According to a preferred embodiment of the invention, the thrust bearing sheet is oriented towards and/or away from the end face of the journal bearing, the end face of the journal bearing being provided with a lubricating layer consisting of a binder and a modifying additive.

According to a preferred embodiment of the present invention, the binder is selected from: alkyd resin, polyacrylate, epoxy resin, phenolic resin, silicone resin, polyformaldehyde, polyamide, polyurethane, polyphenylene sulfide, fluoropolymer, polyether ether ketone, polyimide resin, silicate, phosphate, borate, ceramic and a mixture formed by combining one or more of the modified substances of any one of the materials.

According to a preferred embodiment of the present invention, the modifying additive is selected from: graphite, carbon nano-tube, polytetrafluoroethylene, ultra-high molecular weight polyethylene, molybdenum disulfide, tungsten disulfide, zinc sulfide, calcium fluoride, boron nitride, metallic lead, metallic silver and metallic bismuth.

On the basis of the common knowledge in the field, the above preferred embodiments can be combined arbitrarily to obtain the preferred embodiments of the present invention.

Other systems, methods, features and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the invention, and be protected by the accompanying claims.

Drawings

For a better understanding of the above and other objects, features, advantages and functions of the present invention, reference should be made to the preferred embodiments illustrated in the accompanying drawings. Like reference numerals in the drawings refer to like parts. It will be appreciated by persons skilled in the art that the drawings are intended to illustrate preferred embodiments of the invention without any limiting effect on the scope of the invention, and that the various components in the drawings are not to scale.

FIG. 1 is a schematic view of a wind turbine;

2A-2B are perspective views of different embodiments of a radial plain bearing according to the present invention;

FIG. 3 is a perspective view of a thrust bearing sheet of a plain bearing assembly according to the present invention;

4A-4E are schematic illustrations of longitudinal cross-sections of different embodiments of radial plain bearings;

fig. 5 is a schematic view of the operation of a propeller shaft employing a plain bearing assembly of the present invention.

Description of reference numerals:

supporting columns: 1;

a nacelle: 2;

a blade: 3;

radial sliding bearing: 10;

a first oil hole: 11;

inner wall surface of radial sliding bearing: 12;

outer wall surface of radial sliding bearing: 13;

thrust bearing piece: 20;

second end face of thrust bearing sheet: 21;

a second oil hole: 22;

an oil storage tank: 23.

Detailed Description

The inventive concept will be described in detail below with reference to the accompanying drawings. What has been described herein is merely a preferred embodiment in accordance with the present invention, and those skilled in the art will appreciate that other ways of implementing the present invention on the basis of the preferred embodiment will also fall within the scope of the present invention. In the following detailed description, directional terms, such as "upper", "lower", "longitudinal", "lateral", and the like, are used with reference to the orientation depicted in the accompanying drawings. The components of embodiments of the present invention can be positioned in a number of different orientations and the directional terminology is used for purposes of illustration and is in no way limiting.

The sliding bearing assembly of the present disclosure includes the radial sliding bearing 10 shown in fig. 2, the thrust bearing sheet 20 shown in fig. 3, and a bearing seat, not shown. The bearing seats for holding the journal bearing 10 and the thrust bearing sheet 20 have receiving grooves adapted to the shape of the journal bearing 10 and the thrust bearing sheet 20, respectively, which are conventional in the art and thus will not be described herein.

The radial plain bearing 10 is of cylindrical configuration having an inner cavity for supporting a drive shaft 30 located within the gearbox 4 of a wind turbine. The sliding bearing assembly of the present disclosure is applicable not only to the one-piece propeller shaft 30 shown in fig. 1, but also to a composite propeller shaft in which a plurality of segments of propeller shafts are combined by flange connection or the like. For a compound driveshaft, the plain bearing assembly of the present disclosure is adapted to mate with a driveshaft section located within a gearbox. Further, more preferably, the sliding bearing assembly of the present disclosure is also applicable to other rotating members of the nacelle step-up gear box 4. The unitary driveshaft shown in fig. 1, the driveshaft section where the unitized driveshaft is located within gearbox 4, and other rotating components suitable for use in the plain bearing assembly of the present disclosure will be collectively referred to hereinafter as "driveshaft 30".

Referring to fig. 2A, the radial sliding bearing 10 has a plurality of first oil holes 11 extending in the wall thickness direction thereof. The first oil holes 11 are arranged at equal intervals in both the longitudinal direction and the circumferential direction of the radial sliding bearing 10; the first oil holes 11 of adjacent rows are staggered along the length of the radial sliding bearing 10, and the first oil holes 11 distributed in this way help to form an oil film layer with relatively uniform pressure on the surface of the transmission shaft 30 installed in the inner cavity of the radial sliding bearing 10.

The diameter d of the first oil hole 11 is optionally set to 25mm, 15mm, 10mm, 5mm, 3mm, 1mm, etc., which may be selected according to the overall size of the radial sliding bearing 10 and the pressure of the injected lubricating oil. Preferably, the total area S1 of the cross-sections of the plurality of first oil holes 11 and the total area S of the outer wall surface 13 of the radial slide bearing 10 should satisfy: 10% S ≧ S1, and more preferably 8% S ≧ S1 ≧ 3% S, can be maintained the structural strength of radial sliding bearing 10 and, under the circumstances, lubricating oil can flow between radial sliding bearing inner and outer wall surfaces 12, 13 with appropriate pressure, thus make lubricating oil realize good dynamic balance.

Alternatively, referring to fig. 2B, the outer wall surface 13 of the radial sliding bearing 10 may be provided with an annular oil groove communicating with the first oil hole 11. Lubricating oil can be injected into the annular oil groove 14 through the bearing housing. Similarly, the inner wall surface 12 of the radial sliding bearing 10 may be provided with an annular oil groove 14.

Referring to fig. 4, which shows a schematic longitudinal cross-sectional view of fig. 2A of a different embodiment of the radial slide bearing 10, it will be appreciated that the complete longitudinal cross-sectional view of the radial slide bearing 10 should also include an underside portion that is symmetrical up and down with respect to the wall of fig. 4. In which fig. 4 only shows the upper part of the longitudinal section of the journal bearing 10 of fig. 2A, in order to clearly show the changes of the inner and outer wall surfaces of the journal bearing wall by means of markings or the like. It will be appreciated that the longitudinal cross-sectional schematic view of the radial sliding bearing 10 of fig. 2B may be seen in fig. 4 except for a slight difference from fig. 4 at the location of the annular oil groove 14.

As shown in fig. 4A to 4E, the wall thickness of the radial slide bearing 10 gradually decreases from the center position OO 'toward both ends of the radial slide bearing 10 in the longitudinal direction AA' of the radial slide bearing 10. In the first embodiment of fig. 4A, the outer diameter of the radial slide bearing 10 is gradually reduced from the axial center OO' toward both ends of the radial slide bearing 10 so that there is at least partial no contact between the outer surface of the radial slide bearing 10 and the opposite inner surface of the bearing housing. Similarly, the radial slide bearing 10 is configured such that the inner diameter thereof gradually increases from the axial center OO' toward both ends of the radial slide bearing 10 so that there is at least partial no contact between the outer surface of the drive shaft 30 and the opposite inner surface of the radial slide bearing 10.

The material of the radial sliding bearing 10 according to the present disclosure may be selected from a copper alloy having good heat dissipation properties. The copper alloy should have a high hardness or the like for withstanding the alternating gravitational load in the radial direction of the drive shaft 30. Preferably, the copper alloy should have the following conditions: the tensile strength is more than or equal to 550MPa, the yield strength (Rp0.2) is more than or equal to 200MPa, the elongation is more than or equal to 5 percent, and the hardness is more than or equal to 100HB (Brinell hardness).

After the drive shaft 30 in a cylindrical configuration is mounted to the journal bearing 10 as shown in fig. 4, and the journal bearing 10 is mounted to the bearing housing (see the surface S for mating with the journal bearing in the bearing housing of fig. 5), contact is made between the journal bearing 10 and the bearing housing, and between the journal bearing 10 and the drive shaft 30 only between the axial center OO' of the journal bearing 10 and its vicinity and the corresponding members. The radial sliding bearing 10 generates a slight clearance between the bearing seat and the drive shaft 30 in other areas.

Preferably, referring to FIG. 4, an outer diameter D of journal bearing 10 at a central location OO 'of journal bearing 10 in a length direction AA' (i.e., the longitudinal direction) is provided₀The outer diameter D of the radial slide bearing 10 at a distance X from the axial center OO_xSatisfies the following conditions: 10^-1≥(D₀-D_x) and/(2X) is not less than 0. Inner diameter d of radial slide bearing 10 at the center position of radial slide bearing 10₀The inner diameter d of the radial slide bearing 10 at a distance X from the axial center OO_xSatisfies the following conditions: 10^-1≥(d_x-d₀)/(2*X)≥0。

In the longitudinal sectional view of the radial sliding bearing 10 of the first embodiment of fig. 4A, the outer wall surface 13 and the inner wall surface 12 of the radial sliding bearing 10 are configured in an arc shape. The radial sliding bearing 10 takes the largest wall thickness at the central position. At this time, the outer diameter D_xPreferably, the following requirements are met: 10^-1≥(D₀-D_x)/(2*X)≥10^-12(ii) a Inner diameter d_xPreferably, the following requirements are met: 10^-1≥(d_x-d₀)/(2*X)≥10^-12。

Outer part of radial plain bearing 10The wall surface 13 and the inner wall surface 12 may not be symmetrical with respect to a center line AA' in the thickness direction of the radial sliding bearing 10 shown in fig. 4A. As a preferred embodiment, the extent of the curvature of the inner wall surface 12 of the radial sliding bearing 10 is greater than the extent of the curvature of the outer wall surface 13 of the radial sliding bearing 10, i.e., (d)_x-d₀)≥(D₀-D_x)。

As an alternative preferred embodiment, the diameter of the outer wall surface 13 and/or the inner wall surface 12 of the radial slide bearing 10 may vary linearly in a longitudinal section of the radial slide bearing 10, i.e. the outer wall surface 13, the inner wall surface 12 are of a conical configuration.

As a preferred embodiment of the radial sliding bearing 10 having the inner wall surface 12 or the outer wall surface 13 of the tapered configuration, in several types of radial sliding bearings 10 shown in fig. 4B to 4E, the inner wall surface 12 and the outer wall surface 13 of the radial sliding bearing 10 are provided as cylindrical surfaces at least in the vicinity of the axial center position thereof. In the non-operating state of the wind turbine, the transmission shaft 30 and the bearing seat have a relatively large contact area with the radial sliding bearing 10 in the corresponding region, and therefore, the maximum load applied to the transmission shaft 30 and the radial sliding bearing 10 can be significantly reduced.

For the embodiments of fig. 4B-4E, the cylindrical surfaces in the inner and/or outer wall surfaces of the radial slide bearing preferably satisfy: 70%. L.gtoreq.l.gtoreq.20%. L, for example, L is 20%. L, 35%. L, 50%. L, 60%. L, etc., where L is the axial extension of the cylindrical surface. The axial center of the cylindrical surface preferably coincides with the axial center of the radial plain bearing, i.e. the distance X' between the axial end of the cylindrical surface and the axial center is: 35% L is more than or equal to X' is more than or equal to 10% L.

Similarly to the first embodiment shown in fig. 4A, the magnitude of the taper of the inner wall surface 12 of the second embodiment shown in fig. 4B is preferably set to be larger than the taper of the outer wall surface 13 of the radial sliding bearing 10.

It should be understood that, based on the inventive concept of the present disclosure, the inner wall surface 12 and the outer wall surface 13 may instead transition in an arc configuration from the end of the cylindrical surface to the portion at the axial ends of the journal bearing 10 in the embodiment of fig. 4B-4D.

See alsoIn fig. 4E, inner wall surface 12 of radial sliding bearing 10 may be provided with a stepped cylindrical surface. Specifically, the cylindrical surface segments X are provided near the axial center and at both ends of the radial sliding bearing 10, respectively₁ ^’、X₂ ^’The two cylindrical surface sections are connected by means of arc transition or conical transition.

Similarly, it is also possible to provide a multi-step cylindrical surface similar to fig. 4E on the outer wall surface 13 of the radial sliding bearing 10, or to provide a multi-step cylindrical surface on both the inner wall surface 12 and the outer wall surface 13 of the radial sliding bearing 10. When the multi-segment cylindrical surface is provided on both the inner wall surface 12 and the outer wall surface 13 of the radial sliding bearing 10, the axial positions of the respective segmented cylindrical surfaces of the inner wall surface 12 and the outer wall surface 13 are preferably set to be the same, which can avoid significant deformation of the radial sliding bearing 10 during long-term use.

In addition, the number of the cylindrical surface segments of the inner wall surface 12 and the outer wall surface 13 of the radial sliding bearing 10 may be set to be more than 3 segments, for example, 4 segments, 5 segments, and so on, according to the load and the size of the radial sliding bearing. A suitable number of cylindrical surface segments may be provided by one skilled in the art based on simulation analysis, etc., based on the teachings of the present disclosure.

Fig. 3 shows a thrust bearing sheet 20 for use with the radial slide bearing 10 of fig. 2. Thrust bearing pieces 20 in an annular configuration are mounted on one end or both ends in the axial direction of the radial slide bearing 10, preferably provided at both ends of the radial slide bearing 10. The thrust bearing sheet 20 serves to receive the axial force of the propeller shaft 30.

The upper surface of the thrust bearing sheet 20 in fig. 3 is a second end surface 21 facing the radial sliding bearing 10, and the lower surface opposite thereto is a first end surface. As shown in fig. 3, the thrust bearing sheet 20 includes at least one second oil hole 22 extending in the wall thickness direction thereof, and the thrust bearing sheet 20 faces one or more oil reservoirs 23 extending in the radial direction on the second end face 21 of the radial slide bearing 10.

Preferably, the inner diameter of the thrust bearing sheet 20 is equal to the inner diameter of the radial slide bearing 10 at the end of the radial slide bearing 10 corresponding thereto, and the axial thrust force received by the radial slide bearing 10 is transmitted to the thrust bearing sheet 20.

In order to establish a reliable layer of lubricating oil film between the axial ends of the radial slide bearing 10 and the thrust bearing sheet 20, according to a preferred embodiment, the thickness of the thrust bearing sheet 20 is arranged to gradually decrease from the inner ring position to the outer ring position of the thrust bearing.

A first end face of the thrust bearing sheet 20 facing away from the journal bearing 10 may be provided as a plane perpendicular to the axial direction thereof. Thereby, the thrust bearing piece 20 is formed as a slope toward the second end face 21 of the radial slide bearing 10. Specifically, the inclined surface is a side surface of a circular truncated cone whose rotation axis is the center axis of the thrust bearing piece 20.

After the inner diameter of the thrust bearing sheet 20 is set to be the same as the inner diameter of the end of the radial slide bearing 10, as shown in fig. 3, the oil reservoir 23 extends from the inner diameter edge of the thrust bearing sheet 20 to near the outer diameter edge of the thrust bearing sheet 20 in the radial direction of the thrust bearing sheet 20.

Preferably, as shown in fig. 3, the oil reservoir 23 coincides with the second oil hole 22 in the circumferential direction of the thrust bearing piece 20, which facilitates the oil reservoir 23 to hold a surplus of lubricating oil at any time. More preferably, an oil reservoir 23 is also provided at a position adjacent to the periphery of the oil reservoir 23 overlapping the second oil hole 22.

In the embodiment of fig. 3, the oil reservoir 23 is provided at 4 positions uniformly in the circumferential direction of the thrust bearing sheet 20, and the thrust bearing sheet 20 is provided with 3 oil reservoirs 23 of equal circumferential gaps everywhere. The circumferential width of the oil reservoir 23 is preferably set to 6mm or less for ensuring that excessive oil is not kept static and deteriorated.

In order to improve the lubrication performance of the sliding bearing assembly, the inner wall surface 12 and the outer wall surface 13 of the radial sliding bearing 10 and the end surface (second end surface 21) of the thrust bearing sheet 20 facing the radial sliding bearing 10 may be further provided with a lubricating layer composed of a binder and a modifier additive.

The binder in the lubricating layer may be selected from: alkyd resin, polyacrylate, epoxy resin, phenolic resin, silicone resin, polyoxymethylene, polyamide, polyurethane, polyphenylene sulfide, fluoropolymer, polyether ether ketone, polyimide resin, silicate, phosphate, borate, ceramic, and a modified product of any of the above materials, or a mixture of a plurality of the above materials in combination.

The modifying additive in the lubricating layer may be selected from: graphite, carbon nano-tube, polytetrafluoroethylene, ultra-high molecular weight polyethylene, molybdenum disulfide, tungsten disulfide, zinc sulfide, calcium fluoride, boron nitride, metallic lead, metallic silver and metallic bismuth, or a mixture formed by combining a plurality of the materials.

The operation mechanism of the sliding bearing assembly of the present invention is described below with reference to fig. 5, in which fig. 5 is a schematic view along the axial direction of the transmission shaft 30. As described above, after the slide bearing assembly is mounted, a slight gap is generated between the radial slide bearing 10 and the bearing housing, the drive shaft 30. After the blades 3 and the transmission shaft 30 are driven to rotate by wind power, under the condition that lubricating oil is injected into the outer part through the oil hole of the radial sliding bearing 10, the lubricating oil with certain pressure is extruded by the transmission shaft 30, and the pressure is further increased. The high-pressure lubricating oil flows to the gap formed by the inner wall surface 12 of the radial sliding bearing 10 and the outer surface of the propeller shaft 30. Under the vibration and rotation of the transmission shaft 30, the high-pressure oil generates a partial velocity in both the radial direction and the axial direction of the transmission shaft 30, and the high-pressure oil starts to flow in all directions and lift the transmission shaft 30 from the inner wall surface 12 of the radial sliding bearing 10. In particular, in the case where the inner diameter of the radial sliding bearing 10 is set to the arc-shaped configuration, the high-pressure lubrication oil at different positions may exhibit a more complicated flowing state, and the high-pressure lubrication oil is more favorable for establishing an oil film layer between the propeller shaft 30 and the radial sliding bearing 10 more quickly and for a longer time, so that the propeller shaft 30 is maintained in the suspended state shown in fig. 5 for a long period of time. Therefore, the sliding bearing according to the present disclosure is utilized in a wind power generator.

Similarly to the inner surface of the radial slide bearing 10, in the case where the outer wall surface 13 of the radial slide bearing 10 is provided in an irregular cylindrical shape, that is, in the case where the outer surface of the radial slide bearing 10 is formed in an arcuate configuration in a longitudinal section of the radial slide bearing 10, an oil film layer can be established between the outer wall surface 13 of the radial slide bearing 10 and the opposed surface S of the bearing housing, based on the similar case of the inner wall surface 12 of the radial slide bearing 10 described above. At this point, the radial sliding bearing 10 will be disengaged from the bearing seat. In the case where the drive shaft 30 rotates at a high speed, the radial sliding bearing 10 can synchronously rotate at a low speed, which results in further reduction of the frictional force to which the drive shaft 30 is subjected.

For the thrust bearing sheet 20 located at the axial end of the radial slide bearing 10, the configuration in which the wall thickness is gradually reduced from the inner ring position to the outer ring position of the thrust bearing similarly forms an oil film layer between the second end face 21 of the thrust bearing sheet 20 and the end face of the radial slide bearing 10.

In the case of a change in the force of natural wind or the direction of the wind, the inner surface of the radial sliding bearing 10 is first subjected to a potential impact. As the above-described most preferable embodiment, that is, the embodiment in which the bending width of the inner wall surface 12 of the radial sliding bearing 10 is set to be larger than the bending width of the outer wall surface 13 of the radial sliding bearing 10, the presence of relatively large amounts of lubricating oil in the inner wall surface 12 and the bearing outer surface of the radial sliding bearing 10 will more favorably alleviate the impact action.

As can be seen from the above description, the sliding bearing assembly of the present invention can ensure that the transmission shaft 30 is fixed in the inner cavity of the radial sliding bearing 10 in a "floating rotation" manner, thereby ensuring that it can be applied to the operating environment of the wind turbine. Furthermore, the journal bearing 10 can also be maintained in a suspended state, which results in a longer service life of the journal bearing 10, thereby providing a low maintenance cost feature of the plain bearing assembly according to the present disclosure.

The scope of protection of the present invention is limited only by the claims. Persons of ordinary skill in the art, having benefit of the teachings of the present invention, will readily appreciate that alternative structures to those disclosed as possible may be substituted for the alternative embodiments disclosed, and that the disclosed embodiments may be combined to create new embodiments, which likewise fall within the scope of the appended claims.

Claims

1. A plain bearing assembly adapted for use with a drive shaft of a wind generator, the plain bearing assembly comprising:

a radial plain bearing of a cylindrical configuration having an inner cavity for supporting the drive shaft, the radial plain bearing having a plurality of first oil holes extending in a wall thickness direction thereof; and

a bearing housing configured to hold the radial sliding bearing;

it is characterized in that the preparation method is characterized in that,

the wall thickness of the journal bearing is gradually reduced from the axial center toward both ends of the journal bearing in the axial direction of the journal bearing.

2. A plain bearing assembly according to claim 1, in which the journal bearing is configured such that its outer diameter tapers from the axial centre towards both ends of the journal bearing so that there is at least partial lack of contact between the outer wall surface of the journal bearing and the opposite inner surface of the bearing seat.

3. A plain bearing assembly according to claim 2, wherein the plain radial bearing is configured such that its inner diameter gradually increases from the axial center toward both ends of the plain radial bearing, so that there is at least partial no contact between the outer wall surface of the drive shaft and the opposite inner surface of the plain radial bearing.

4. A plain bearing assembly according to claim 3, in which the radial plain bearing satisfies: 10^-1≥(D₀-D_x) /(2X X) ≧ 0, where D₀Is the outer diameter of the journal bearing at the axial center position, D_xIs the outer diameter of the radial sliding bearing at a position at a distance X from the axial center.

5. A plain bearing assembly according to claim 4, wherein the radial plain bearing satisfies: 10^-1≥(d_x-d₀) /(2X X) ≧ 0, where d₀Is the radial slideInner diameter of the movable bearing at the axial center position, d_xIs the inner diameter of the radial sliding bearing at a position at a distance X from the axial center.

6. A plain bearing assembly according to claim 5, wherein, in longitudinal cross-section of the plain radial bearing, the outer and/or inner wall surface of the plain radial bearing is of arcuate configuration.

7. A plain bearing assembly according to claim 5, wherein, in longitudinal cross-section of the plain radial bearing, the outer and/or inner wall surface of the plain radial bearing is of tapered configuration.

8. A plain bearing assembly according to claim 6, wherein at least a part of the inner and/or outer wall surfaces of the radial plain bearing is a cylindrical surface, and the cylindrical surface satisfies: l is more than or equal to 70% L and more than or equal to 20% L, wherein L is the axial length of the radial sliding bearing; l is the axial extension of the cylindrical surface.

9. A plain bearing assembly according to claim 7, wherein at least a portion of the inner and/or outer wall surfaces of the radial plain bearing is a cylindrical surface and the cylindrical surface satisfies: l is more than or equal to 70% L and more than or equal to 20% L, wherein L is the axial length of the radial sliding bearing; l is the axial extension of the cylindrical surface.

10. The plain bearing assembly of claim 1, wherein the diameter d of the first oil hole is: d is more than or equal to 25mm and more than or equal to 1 mm.

11. The plain bearing assembly according to claim 1, wherein a total area S1 of cross sections of the plurality of first oil holes and a total area S of the outer wall surface of the radial plain bearing satisfy: 10% S is greater than or equal to S1.

12. A plain bearing assembly according to any of claims 1 to 11, wherein the plain bearing assembly further comprises a thrust bearing sheet of annular configuration, wherein the thrust bearing sheet is mountable on at least one end of the radial plain bearing in the axial direction.

13. The plain bearing assembly according to claim 12, wherein the thrust bearing sheet includes at least one second oil hole extending in a wall thickness direction thereof.

14. The plain bearing assembly of claim 13, wherein the thickness of the thrust bearing sheet decreases from the inner ring position to the outer ring position of the thrust bearing, and the inner diameter of the thrust bearing sheet is equal to the plain bearing inner diameter of the end of the plain radial bearing corresponding thereto.

15. A plain bearing assembly according to claim 13, wherein the first end face of the thrust bearing sheet facing away from the journal bearing is a plane perpendicular to its axial direction.

16. A plain bearing assembly according to claim 15, wherein the second end face of the thrust bearing sheet facing the journal bearing is provided with at least one oil reservoir extending in the radial direction thereof.

17. The plain bearing assembly according to claim 1, characterized in that the inner wall surface and/or the outer wall surface of the radial plain bearing has at least one annular oil groove communicating with the first oil hole.

18. A plain bearing assembly according to claim 1, characterized in that the inner and/or outer wall surface of the radial plain bearing is provided with a lubricating layer consisting of a binder and a modifying additive.

19. A plain bearing assembly according to claim 12, wherein the end face of the thrust bearing sheet facing the journal bearing and/or the end face facing away from the journal bearing is provided with a lubricating layer consisting of a binder and a modifying additive.