CN113864330A

CN113864330A - Self-aligning variable-pitch bearing

Info

Publication number: CN113864330A
Application number: CN202111308112.XA
Authority: CN
Inventors: 郭玉飞; 徐猛; 张丽娜; 杜姗珊; 孙晓旭; 肖长春; 杨金雷; 田琳; 王迪; 吕宝; 武广富
Original assignee: Wafangdian Bearing Group National Bearing Engineering Technology Research Center Co Ltd
Current assignee: Wafangdian Bearing Group National Bearing Engineering Technology Research Center Co Ltd
Priority date: 2021-11-05
Filing date: 2021-11-05
Publication date: 2021-12-31
Anticipated expiration: 2041-11-05
Also published as: CN113864330B

Abstract

The invention belongs to the technical field of bearing equipment manufacturing, and in particular relates to a self-aligning pitch bearing, comprising a first outer ring, a second outer ring, an inner ring and rollers, wherein the outer diameter of the inner ring is provided with an annular boss, the annular The two sides of the boss are respectively provided with a first outer ring and a second outer ring, the two sides of the annular boss form a first raceway and a second raceway, and the two rows of tapered rollers are respectively installed on the first raceway and the second raceway. In the second raceway, the outer circular surface of the annular boss forms the third raceway, and the self-aligning roller is installed in the third raceway. The pitch bearing of the present invention improves the problem of uneven load distribution while continuously improving the bearing capacity.

Description

Self-aligning variable-pitch bearing

Technical Field

The invention belongs to the technical field of bearing equipment manufacturing, and particularly relates to a self-aligning variable-pitch bearing.

Background

With the gradual recognition of people on clean energy in recent years, the cognition of people on wind power generation is also deep, and the occupation ratio of wind power generation units is larger and larger. Wind energy is increasingly gaining attention as a clean renewable energy source in all countries of the world. Wind power generation has rapidly developed worldwide and even becomes the main source of electricity in some countries. With the continuous development of the wind power industry, the small-power small-megawatt wind turbine set gradually loses the competitive advantage, and the whole machine manufacturing enterprises at home and abroad are eagerly developing the large-power large-impeller-diameter wind turbine set with the power of 3.0MW and above 3.0 MW.

The variable pitch bearing is an indispensable key part in the design of the whole fan, bears the influence of axial load, radial load and overturning moment during working, and has the characteristics of complex working condition load condition, poor working condition environment, lower overall rigidity and the like, so that the strength of the variable pitch bearing not only influences the overall service life of the bearing, but also has important influence on the overall stability and efficient and safe operation of the wind generating set. The traditional variable-pitch bearing is easy to carry out unbalance loading, so that the load on the whole roller path of the bearing is not uniformly distributed, and the problems of early failure and the like are caused.

Disclosure of Invention

According to the defects in the prior art, the invention aims to provide a bearing with a high bearing and compact structure, which is mainly applied to a variable-pitch bearing of a large-megawatt large-blade wind generating set and is used for solving the problem of uneven load distribution in the operation process of the traditional three-row cylindrical roller variable-pitch bearing.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: the self-aligning variable pitch bearing comprises a first outer ring, a second outer ring, an inner ring and rollers, wherein an annular boss is arranged on the outer diameter of the inner ring, the first outer ring and the second outer ring are respectively arranged on two sides of the annular boss, a first roller path and a second roller path are formed on two side faces of the annular boss, two rows of tapered rollers are respectively installed in the first roller path and the second roller path, a third roller path is formed on the outer circular face of the annular boss, and the aligning rollers are installed in the third roller path.

Further, the two rows of tapered rollers are axial tapered rollers bearing axial loads.

Furthermore, the aligning roller is a radial aligning roller bearing a radial load, and the third raceway is an arc raceway.

Further, the third raceway is arranged in the middle of the outer circular surface of the annular boss.

Further, the first outer ring and the second outer ring are positioned in a matched mode through a trapezoid table to form an outer ring of the variable-pitch bearing together.

Further, the large end sides of the two rows of tapered rollers are close to the end where the roller contact stress is large.

Further, the inner ring or the outer ring of the variable pitch bearing is connected with the blade structure, and the large end sides of the two rows of tapered rollers are close to the blade structure.

Further, the first raceway and the second raceway are of unequal length structures.

Furthermore, two sides of the variable-pitch bearing are connected with the hub structure through an inner ring or an outer ring, and an axial raceway close to the hub side is longer than an axial raceway on the other side.

Further, a sealing ring is arranged between the first outer ring and the inner ring, and a sealing ring is arranged between the second outer ring and the inner ring.

The invention has the beneficial effects that: the variable-pitch bearing disclosed by the invention has the advantage that the problem of uneven load distribution is solved under the condition of continuously improving the bearing capacity of the bearing.

Drawings

FIG. 1 is a schematic view of a pitch bearing configuration;

FIG. 2 is an enlarged view of the axial tapered roller;

FIG. 3 is an enlarged view of a radially aligning roller;

FIG. 4 is contact stress at maximum contact force of the blade side roller;

FIG. 5 is the contact stress at maximum contact force of the hub side roller;

in the figure: 1. the device comprises a first outer ring, a second outer ring, 3, an inner ring, 4, an axial tapered roller, 5, a radial aligning roller, 6 and a sealing ring.

Detailed Description

In order to make the structure and function of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention.

Referring to the attached drawings 1-3, the self-aligning variable pitch bearing comprises a first outer ring 1, a second outer ring 2, an inner ring 3 and rollers, wherein an annular boss is arranged on the outer diameter of the inner ring 3, the first outer ring 1 and the second outer ring 2 are respectively arranged on two sides of the annular boss, a first rolling path and a second rolling path are formed on two side surfaces of the annular boss, two rows of tapered rollers 4 are respectively arranged in the first rolling path and the second rolling path, and the two rows of tapered rollers are axial tapered rollers bearing axial loads; the outer circle surface of the annular boss forms a third raceway, the third raceway is an arc raceway, the aligning roller 5 is installed in the third raceway, and the aligning roller is a radial aligning roller bearing a radial load.

Furthermore, the third raceway is arranged in the middle of the outer circular surface of the annular boss, so that stress is balanced.

Further, the first outer ring 1 and the second outer ring 2 are positioned in a matched mode through a trapezoid table to form an outer ring of the variable-pitch bearing together.

Further, the inner ring 3 or the outer ring of the variable pitch bearing is connected with a blade structure, the other side of the variable pitch bearing is connected with a hub structure, and the large end sides of the two rows of tapered rollers 4 are close to the blade structure. In the embodiment, fig. 1-3 illustrate an inner ring connecting blade structure and an outer ring side connecting hub structure, that is, the large end sides of two rows of tapered rollers are close to the inner ring.

Further, the first raceway and the second raceway are of unequal length structures. Two sides of the variable pitch bearing are connected with the hub structure through an inner ring or an outer ring, and an axial raceway close to the hub side is longer than an axial raceway on the other side.

Further, a sealing ring is arranged between the first outer ring 1 and the inner ring 3, and a sealing ring 6 is arranged between the second outer ring 2 and the inner ring 3.

The structure and advantages of the pitch bearing of the invention will be explained in the following by an analysis with specific data.

1) Compared with the structure of the traditional four-point contact ball, the structure of the traditional variable-pitch bearing has the advantages that the structure of the four-point contact ball is changed into a three-row cylindrical roller structure, and two rows of axial rollers and one row of radial rollers have the same size, can bear larger load, and is applied to larger machine types; the same load can be selected for a smaller size bearing, which is a great cost advantage.

2) The three rows of rollers of the traditional three-row roller bearing are all cylindrical roller structures, the bearing capacity of the structure is high, however, unbalance loading is easy to occur in the operation process of the bearing, the load distribution on the whole roller path of the bearing is uneven, and early failure is caused, and the contact stress distribution result of two rows of axial roller paths is shown in fig. 4 and fig. 5 by taking the finite element calculation result of a three-row cylindrical roller variable-pitch bearing of a certain machine type as an example.

In order to improve the phenomenon, the following adjustments are made:

a. and a three-row roller structure is reserved, but two rows of axial rollers are arranged into a tapered roller structure, and the radial rollers are arranged into a self-aligning roller structure.

Based on the current limited analysis result, for two rows of axial raceways, the large end of the tapered roller is arranged at the end with larger contact stress, and the small end is arranged at the other end, so that the problem of uneven stress distribution is solved, the effect of stress matching on the length of the whole raceway is achieved, and the strength and the service life of the whole raceway are improved.

In the three-row roller bearing structure, compared with the size and complexity of the bearing of two rows of rollers in the axial direction, the radial rollers are relatively low in stress, and the rollers at the positions are arranged into a self-aligning structure, so that the rollers can be automatically aligned when the bearing is in an unbalanced load state in the running process, and the optimal state is always maintained to bear the load.

b. The common connection form of the variable pitch bearing, namely an inner ring connection blade structure and an outer ring connection blade structure, is analyzed, and the common trend is that the large end of the roller is placed close to the blade side, and the small end of the roller is placed far away from the blade side.

c. Based on the analysis result of the item b, the two rows of axial raceways are designed into structures with different lengths, so that the strength of the cantilever beam can be improved, and the phenomenon of raceway undercut under a large load is avoided. The lengths of the two axial raceways are determined according to the stress distribution of the two raceways, and the existing structure is that the rolling bodies close to the hub side are longer, so that the stress distribution of the two rows of raceways is more uniform, and the overall safety margin of the bearing can be improved.

The above list is only the preferred embodiment of the present invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.

Claims

1. A self-aligning pitch bearing, characterized in that it comprises a first outer ring, a second outer ring, an inner ring and a roller, the outer diameter of the inner ring is provided with an annular boss, and both sides of the annular boss are respectively provided with There are a first outer ring and a second outer ring. The two sides of the annular boss form a first raceway and a second raceway. Two rows of tapered rollers are installed in the first raceway and the second raceway respectively. The annular boss The outer circular surface of the roller forms the third raceway, and the spherical roller is installed in the third raceway.

2 . The self-aligning pitch bearing according to claim 1 , wherein the two rows of tapered rollers are axial tapered rollers bearing axial loads. 3 .

3 . The self-aligning pitch bearing according to claim 1 , wherein the self-aligning pitch roller is a radial self-aligning roller bearing radial load, and the third raceway is an arc raceway. 4 .

4 . The self-aligning pitch bearing according to claim 1 , wherein the third raceway is arranged in the middle of the outer circular surface of the annular boss. 5 .

5 . The self-aligning pitch bearing according to claim 1 , wherein the first outer ring and the second outer ring are positioned by means of a trapezoidal table to form an outer ring of the pitch bearing. 6 .

6 . The self-aligning pitch bearing according to claim 5 , wherein the large end sides of the two rows of tapered rollers are close to the end where the contact stress of the rollers is larger. 7 .

7 . The self-aligning pitch bearing according to claim 6 , wherein the inner ring or the outer ring of the pitch bearing is connected to the blade structure, and the large ends of the two rows of tapered rollers are close to the blade structure. 8 .

8 . The self-aligning pitch bearing according to claim 1 , wherein the first raceway and the second raceway are of unequal length. 9 .

9 . The self-aligning pitch bearing according to claim 8 , wherein the two sides of the pitch bearing are connected to the hub structure through the inner ring or the outer ring, and the axial raceway near the hub side is longer than the shaft on the other side. 10 . toward the raceway.

10 . The self-aligning pitch bearing according to claim 1 , wherein a sealing ring is arranged between the first outer ring and the inner ring, and a sealing ring is arranged between the second outer ring and the inner ring. 11 .