CN214698811U - Gas bearing and compressor comprising same - Google Patents

Abstract

The invention provides a gas bearing and a compressor comprising the same, relates to the technical field of compressors, and solves the technical problems that a static pressure gas bearing used by a compressor is poor in bearing capacity and a dynamic pressure gas bearing is easy to destabilize. The gas bearing comprises a bearing body, a tilting pad assembly and a shallow cavity assembly which are arranged on the bearing body, and a gas supply assembly which is connected with the tilting pad assembly and the shallow cavity assembly to supply external high-pressure gas; the gas supply assembly is internally provided with a first gas supply unit and a second gas supply unit which are respectively connected with the tilting pad assembly and the shallow cavity assembly in a gas transmission way; the compressor includes a gas bearing. The invention is used for a centrifugal compressor, has the advantages of a tilting pad hydrostatic bearing and a shallow cavity bearing, can ensure that the bearing does not rub a thrust disc in the global operation process of the compressor, thereby influencing the service life of the bearing, and improves the operation stability of a rotor in a high-rotating-speed state.

Description

Gas bearing and compressor comprising same

Technical Field

The invention relates to the technical field of compressors, in particular to a gas bearing and a compressor comprising the same.

Background

The centrifugal compressor is an air-conditioning compressor which utilizes the rotation of a high-speed impeller to generate centrifugal force to compress gas, and the conventional centrifugal compressor has fixed frequency, variable frequency, magnetic suspension and gas suspension at present, wherein the gas suspension centrifugal compressor has the advantages of simple structure, no oil, no friction, low cost and the like, and becomes the development trend of the future centrifugal compressor.

Because the centrifugal compressor is a device for compressing refrigerant, the two ends of the rotor are stressed in different sizes, so that the rotor inevitably moves forwards or backwards, a thrust bearing is required to be arranged in a rotor system to balance the forward or backward force of the rotor, and the stress condition and the working state of the centrifugal compressor are directly influenced by terminal equipment, so that the function of the thrust bearing is very important.

The air suspension centrifugal compressor adopts a gas bearing to support a rotor and balance axial force, and the gas bearing mainly comprises a dynamic pressure gas bearing and a static pressure gas bearing; the dynamic pressure gas bearing is a self-supporting bearing, does not need an additional gas supply system for supplying gas, and mainly works by adopting a dynamic pressure principle; the static pressure gas bearing generates a gas film through an active ventilation mode so as to support the rotor, and the rotor and the bearing cannot rub under the global operation state, so that the static pressure gas bearing is low in loss and long in service life. The dynamic pressure gas bearing needs a certain takeoff rotating speed, and the rotor cannot take off at a low rotating speed; in the starting and stopping stage, friction is generated between the rotor and the bearing, and the bearing capacity of the dynamic pressure gas bearing is relatively low; the static pressure gas bearing has no self-adaptability, so that the rotor is easy to be unstable in operation in a high rotating speed state, and when the air supply pressure difference is large, the bearing generates an air hammer to easily cause instability.

The air suspension compressor generally has high rotating speed, and because the pressure ratio of the centrifugal compressor is large, when a dynamic pressure gas bearing is singly adopted, the bearing capacity of the bearing is insufficient, so that the axial force cannot be well balanced, and when a static pressure bearing is singly adopted, a rotor is stable and volatile at high rotating speed and needs large air supply pressure.

Disclosure of Invention

The invention aims to provide a gas bearing and a compressor comprising the same, and aims to solve the technical problems that the bearing capacity of a static pressure gas bearing used by the compressor is poor and the dynamic pressure gas bearing is easy to destabilize in the prior art.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a gas bearing which comprises a bearing body, a tilting pad assembly, a shallow cavity assembly and a gas supply assembly, wherein the tilting pad assembly and the shallow cavity assembly are arranged on the bearing body, and the gas supply assembly is connected with the tilting pad assembly and the shallow cavity assembly to supply external pressurized gas.

As a further improvement of the invention, the gas supply assembly is internally provided with a first gas supply unit and a second gas supply unit which are respectively connected with the tilting pad assembly and the shallow cavity assembly in a gas transmission way.

As a further improvement of the present invention, the gas supply assembly includes a bearing gas supply plate connected to the bearing body, a shallow gas supply groove and a tilting pad gas supply ring are provided on a side of the bearing gas supply plate facing the bearing body, and the first gas supply unit includes a shallow gas supply hole penetrating through the bearing gas supply plate and communicating with the shallow gas supply groove; the second air supply unit comprises an inclinable pad air supply hole which is arranged on the bearing air supply plate in a penetrating mode and communicated with the inclinable pad air supply ring.

As a further improvement of the invention, the shallow cavity air supply groove and the tilting pad air supply ring are both in circular ring structures, and the centers of the two circular ring structures are superposed.

As a further improvement of the invention, the shallow cavity assembly comprises a shallow cavity air inlet ring which is arranged on one side of the bearing body and is matched with the specification and shape of the shallow cavity air supply groove, a plurality of shallow cavities which are arranged on the other side of the bearing body, and shallow cavity air inlet holes of which two ends are respectively communicated with the shallow cavity air inlet ring and the shallow cavities.

As a further improvement of the invention, the height of the shallow cavity air inlet ring is smaller than the depth of the shallow cavity air supply groove.

As a further development of the invention, all of the shallow cavities are arranged in the shape of a circular ring along the center of the bearing body.

As a further improvement of the present invention, the tilting pad assembly includes a tilting pad air inlet groove disposed on one side of the bearing body and having a specification shape adapted to the tilting pad air supply ring, a tilting pad disposed in the shallow cavity, a porous mass disposed above the tilting pad, and a tilting pad air inlet hole disposed on the tilting pad and communicating with the tilting pad air inlet groove and the shallow cavity.

As a further improvement of the invention, the tilting pad is also provided with a supporting rib for preventing the porous mass from being broken.

As a further improvement of the invention, the diameter of the shallow cavity air inlet hole is 0.6-1 mm.

The invention provides a compressor, which comprises the gas bearing.

As a further development of the invention, the compressor is a centrifugal compressor.

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

the gas bearing provided by the invention is a tilting pad thrust gas bearing with high stability and high bearing capacity and without global friction loss, has the advantages of a tilting pad hydrostatic bearing and a shallow cavity bearing, can ensure that the bearing does not rub a thrust disc in the global operation process of a compressor, thereby influencing the service life of the bearing, and improves the operation stability of a rotor in a high-rotating-speed state; the gas supply components in the gas bearing are respectively connected with different gas supply pipelines, and the tilting pad components and the shallow cavity components in the gas bearing are supplied with gas by two paths, so that the optimum pressure can be supplied to different gas bearing parts, the capability of the bearing is ensured to the maximum extent, the reliability of the bearing is improved, and the gas supply quantity can be reduced aiming at the capability of different bearings under the high-speed state, and the power consumption of a gas supply system is reduced to the maximum extent.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a front sectional view of a gas bearing of the present invention;

FIG. 2 is a top view of the gas bearing of the present invention;

FIG. 3 is a front sectional view of a bearing body in the gas bearing of the present invention;

FIG. 4 is a top view of a bearing body in the gas bearing of the present invention;

FIG. 5 is a front sectional view of a bearing gas supply plate in the gas bearing of the present invention;

FIG. 6 is a top view of a bearing gas feed plate in the gas bearing of the present invention.

In figure 1, a bearing body; 11. a locking hole; 2. a tiltable tile assembly; 21. the tilting pad air inlet groove; 22. a tilt pad; 23. a porous mass; 24. an air inlet hole of the tilting pad; 25. supporting ribs; 3. a shallow cavity assembly; 31. a shallow cavity air inlet ring; 32. a shallow cavity; 33. a shallow cavity air inlet; 4. a gas supply assembly; 41. a bearing gas supply plate; 42. a shallow cavity air supply slot; 43. a tilting pad gas supply ring; 44. a shallow cavity gas supply hole; 45. an air supply hole of the tilting pad; 46. and locking the threaded hole.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

As shown in fig. 1, the present invention provides a gas bearing, which comprises a bearing body 1, a tilting pad assembly 2 and a shallow cavity assembly 3 arranged on the bearing body 1, and a gas supply assembly 4 connected with both the tilting pad assembly 2 and the shallow cavity assembly 3 for supplying external pressurized gas. It should be noted here that the supplied pressurized gas refers to a gas having a pressure greater than the ambient atmospheric pressure.

As an alternative embodiment of the present invention, as shown in fig. 1 and 2, the gas supply assembly 4 has a first gas supply unit and a second gas supply unit connected to the tilting pad assembly 2 and the shallow chamber assembly 3 respectively for gas transmission. It should be noted that the air sources of the first air supply unit and the second air supply unit may be the same or different, as long as two air supplies can be adopted to respectively provide the air with the required pressure to different positions of the bearing, and the air supply pressure regulation and supply of the two air supply units are controlled independently from each other. Through the arrangement, a bearing structure with two parts supplying air independently is formed, and air with different flow rates is supplied to different bearing parts, so that the bearing operates in the optimal state, and the reliability of the bearing is improved.

The gas bearing provided by the invention is a tilting pad thrust gas bearing with high stability and high bearing capacity and without global friction loss, has the advantages of a tilting pad static pressure bearing and a shallow cavity bearing, can ensure that a rotor does not rub a thrust disc in the global operation process of a compressor, thereby influencing the service life of the rotor, and improves the operation stability of the rotor in a high-speed state, and is more stable in a high-speed state; the gas supply components in the gas bearing are respectively connected with different gas supply pipelines, and the tilting pad components and the shallow cavity components in the gas bearing are supplied with gas by two paths, so that the optimum pressure can be supplied to different gas bearing parts, the capability of the bearing is ensured to the maximum extent, the reliability of the bearing is improved, and the gas supply quantity can be reduced aiming at the capability of different bearings under the high-speed state, and the power consumption of a gas supply system is reduced to the maximum extent.

As shown in fig. 5 and 6, the gas supply assembly 4 further includes a bearing gas supply plate 41 connected to the bearing body 1, the bearing gas supply plate 41 is provided with a shallow cavity gas supply groove 42 and a tilting pad gas supply ring 43 toward the bearing body 1, and the first gas supply unit includes a shallow cavity gas supply hole 44 penetrating through the bearing gas supply plate 41 and communicating with the shallow cavity gas supply groove 42; the second air supply unit includes a tilting pad air supply hole 45 penetrating through the bearing air supply plate 41 to communicate with the tilting pad air supply ring 43.

Specifically, the bearing air supply plate 41 is provided with two air supply holes, namely a tilting pad air supply hole 45 and a shallow cavity air supply hole 44, the center positions of the two holes are different, the two air supply holes are respectively arranged on the shallow cavity air supply groove 42 and the tilting pad air supply ring 43, the two air supply holes are respectively connected with different air supply pipelines, and two air supply paths are adopted; the bearing air supply plate 41 is also designed with a locking threaded hole 46.

In an alternative embodiment of the present invention, the shallow cavity air supply groove 42 and the tilting pad air supply ring 43 are both circular ring structures, and their centers coincide. Specifically, the shallow cavity air feed slot 42 is located outside the tilting pad air feed ring 43.

As shown in fig. 3 and 4, the shallow cavity assembly 3 further includes a shallow cavity air intake ring 31 disposed on one side of the bearing body 1 and adapted to the specification and shape of the shallow cavity air supply groove 42, a plurality of shallow cavities 32 disposed on the other side of the bearing body 1, and shallow cavity air intake holes 33 having two ends respectively communicated with the shallow cavity air intake ring 31 and the shallow cavities 32.

By arranging the shallow cavity assembly, the gas bearing is a thrust gas bearing structure with a shallow cavity structure, the dynamic pressure effect is enhanced in a high-speed state, and the bearing capacity can be improved.

As an alternative embodiment of the present invention, the height of the shallow cavity feed ring 31 is less than the depth of the shallow cavity feed slots 42. When the bearing body 1 and the bearing air supply plate 41 are connected together, there is a space between the end of the cavity air supply ring 31 and the bottom of the cavity air supply groove 42, which forms an annular cavity air supply channel along which pressurized air is supplied to flow and to the cavities 32 at different positions of the bearing body 1 through the cavity air supply holes 33.

Further, all the shallow cavities 32 are arranged in a circular ring shape along the center of the bearing body 1. Each cavity 32 is a ring sector structure, but the cavities 32 may be arranged in other regular or irregular shapes such as circle, triangle, rectangle, trapezoid, polygon, etc.

As an alternative embodiment of the present invention, the tilting pad assembly 2 includes a tilting pad air inlet groove 21 disposed on one side of the bearing body 1 and having a specification shape matched with the tilting pad air supply ring 43, a tilting pad 22 disposed in the shallow cavity 32, a porous block 23 disposed above the tilting pad 22, and a tilting pad air inlet hole 24 disposed on the tilting pad 22 and communicating with the tilting pad air inlet groove 21 and the shallow cavity 32.

The gas bearing of the invention is a porous static pressure gas bearing with a tilting pad structure, which increases the self-adaptability and damping characteristic of the whole bearing, improves the operation stability and reliability of the whole rotor system, and the tilting pad 22 is also provided with a support rib 25 for preventing the porous mass 23 from being broken.

As shown in fig. 4, the number of the support ribs 25 is four, and the support ribs are divided into two groups and symmetrically arranged along the symmetry center line of the tilt pad 22.

Further, the diameter of the shallow cavity air inlet hole 33 is 0.6-1 mm.

Example 1:

the gas bearing comprises a bearing body 1, wherein a locking hole 11, a shallow cavity air inlet ring 31 and a tilting pad air inlet groove 21 are designed on the bearing body 1; the shallow cavity air inlet ring 31, the tilting pad air inlet groove 21, the shallow cavity air supply groove 42 on the bearing air supply plate 41 and the tilting pad air supply ring 43 are matched with each other and are connected together by penetrating screws through the locking hole 11 and the locking threaded hole 46, so that a reliable air supply assembly 4 is formed; the bearing body 1 mainly comprises a shallow cavity 32 and a tilting pad 22, wherein the tilting pad 22 is also provided with a porous block 23, the tilting pad 22 can adjust the position thereof along with the change of load (the specific adjusting position refers to the turning along the symmetrical line of the tilting pad 22), so that the bearing reliability is improved, but the bearing capacity of the tilting pad bearing is low, therefore, in the invention, the bearing mainly plays a role in low-speed and start-stop stages, the dynamic pressure effect of the shallow cavity bearing is enhanced in a high-speed state, the static pressure bearing is large, therefore, in a high-speed state, the shallow cavity bearing mainly plays a role, at the moment, the air supply pressure can be adjusted to match different working states, the two bearing forms are mutually matched, so that the bearing has large bearing capacity and higher reliability; the shallow cavity 32 is further designed with a shallow cavity air supply hole 33 (generally 0.6-1mm), the tilting pad 22 is designed with a tilting pad air inlet hole 24 and a support rib 25, and the support rib 25 is mainly used for improving the strength and preventing the porous mass 23 from being broken.

The invention also provides a compressor comprising the gas bearing.

Further, the compressor is a centrifugal compressor.

The invention provides a tilting pad thrust gas bearing with high load bearing and high stability and without friction loss in the whole domain, which has larger load bearing capacity and self-adaptability (the angle of a pad is automatically adjusted to adapt to the running change of a rotor according to the load change), so that the tilting pad thrust gas bearing has better reliability; the bearing has the characteristics of a tilting pad static pressure gas bearing and a shallow cavity dynamic and static pressure gas bearing, namely the stability of the tilting pad gas bearing and the large bearing of the shallow cavity bearing, and because the bearing has a tilting pad part, the bearing has good adaptability, under the conditions of starting and stopping and low speed, the load is lower, the tilting pad part of the bearing provides main bearing to enable a rotor to float, the bearing can not rub a thrust disc any more, under the high-speed running condition, the load is increased, the rotor vibration is intensified, the tilting pad bearing part can be freely deformed to adapt to the running change of the rotor, the dynamic pressure effect of the shallow cavity part and the tilting pad part in the bearing is increased, the bearing capacity of the bearing is increased, the rotor is enabled to stably float, at the moment, the static pressure part only needs to supplement certain bearing, and the fixed part of the bearing can provide enough bearing capacity for the bearing, the defect of insufficient bearing capacity of the tilting pad part is made up, so that the air supply power consumption can be reduced, and the tilting pad part has self-adaptability, so that extra damping can be provided for a bearing, and the vibration of a rotor at a high speed is reduced; the bearing is simple to process, and the service life of the bearing is prolonged.

After the invention is used, because the rotor can be supported by the tilting pad static pressure gas bearing in the starting and stopping stage of the rotor, the rotor does not need to reach higher flying rotating speed, and the difficulty of program control of the frequency converter is reduced;

after the invention is used, the tilting pad static pressure gas bearing and the shallow cavity dynamic and static pressure gas bearing provide bearing capacity simultaneously, and the bearing does not need higher gas supply pressure (the dynamic pressure effect of the shallow cavity bearing is enhanced in a high-speed running state). Thus reducing the load and power consumption of the external air supply system;

after the bearing is used, the bearing is easy to process, and the porous mass is a local porous mass, so that when one of the porous masses is damaged, only the porous mass can be replaced, and the material cost is saved.

It should be noted that "inward" is a direction toward the center of the accommodating space, and "outward" is a direction away from the center of the accommodating space.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in fig. 1 to facilitate the description of the invention and to simplify the description, but are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered as limiting the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (10)

1. The utility model provides a gas bearing which characterized in that, includes the bearing body, sets up tilting pad subassembly and shallow chamber subassembly on the bearing body and with tilting pad subassembly with the shallow chamber subassembly all is connected in order to supply the outside gas supply subassembly of taking pressure.

2. A gas bearing according to claim 1 wherein the gas supply assembly has first and second gas supply units therein in gas delivery connection with the tilting pad assembly and the shallow cavity assembly respectively.

3. The gas bearing of claim 2, wherein the gas supply assembly comprises a bearing gas supply plate connected to the bearing body, the bearing gas supply plate being provided with a shallow cavity gas supply groove and a tiltable bush gas supply ring on a side facing the bearing body, the first gas supply unit comprising a shallow cavity gas supply hole penetrating the bearing gas supply plate and communicating with the shallow cavity gas supply groove; the second air supply unit comprises an inclinable pad air supply hole which is arranged on the bearing air supply plate in a penetrating mode and communicated with the inclinable pad air supply ring.

4. A gas bearing according to claim 3 wherein the shallow cavity gas feed groove and the tiltable pad gas feed ring are both circular ring structures and have their centers coincident.

5. The gas bearing of claim 3, wherein the shallow cavity assembly comprises a shallow cavity air inlet ring arranged on one side of the bearing body and matched with the specification and shape of the shallow cavity air supply groove, a plurality of shallow cavities arranged on the other side of the bearing body, and shallow cavity air inlet holes with two ends respectively communicated with the shallow cavity air inlet ring and the shallow cavities.

6. The gas bearing of claim 5 wherein the shallow cavity gas feed ring height is less than the shallow cavity gas feed groove depth.

7. A gas bearing according to claim 5, wherein all of the shallow cavities are arranged in a circular ring shape along the centre of the bearing body.

8. A gas bearing according to claim 5 wherein said tilting pad assembly comprises a tilting pad air inlet channel disposed on one side of said bearing body and having a gauge shape adapted to said tilting pad air ring, a tilting pad disposed in said shallow cavity, a porous mass disposed above said tilting pad, and a tilting pad air inlet aperture disposed on said tilting pad in communication with said tilting pad air inlet channel and said shallow cavity.

9. A gas bearing according to claim 8 wherein the tilting pads are further provided with support ribs.

10. A compressor, characterized by comprising a gas bearing according to any one of claims 1-9.

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