CN215171567U

CN215171567U - Gas bearing and compressor

Info

Publication number: CN215171567U
Application number: CN202023184244.XU
Authority: CN
Inventors: 董明珠; 刘华; 张治平; 杨玉明
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2020-12-25
Filing date: 2020-12-25
Publication date: 2021-12-14
Anticipated expiration: 2030-12-25

Abstract

The present disclosure relates to a gas bearing and a compressor. The gas bearing includes: a bearing housing (10) having an axially extending inner cavity comprising at least one static pressure mounting section (11b) and at least one dynamic pressure mounting section (11a) arranged in an axial direction; at least one porous material inner sleeve (20) respectively arranged in the at least one static pressure mounting section (11 b); at least one elastic material layer (30) respectively disposed in the at least one dynamic pressure mounting section (11 a); and at least one top foil (40) respectively arranged inside the at least one layer of elastomeric material (30), wherein the inner diameter d2 of the at least one inner sleeve (20) of porous material is smaller than the inner diameter d1 of the at least one top foil (40). The embodiment of the disclosure can provide good support for the rotor with a larger rotating speed range, and can meet the working requirement of severe working conditions.

Description

Gas bearing and compressor

Technical Field

The disclosure relates to the field of bearings, in particular to a gas bearing and a compressor.

Background

Gas bearings are a type of bearing in which gas acts as a lubricating medium, and a lubricating gas film that supports a load is formed by utilizing the dynamic pressure effect or static pressure effect of a gas fluid. In the related art, gas bearings are classified into dynamic pressure gas bearings, static pressure gas bearings, and squeeze type gas bearings according to the mechanism of generation of a lubricating gas film. The gas bearing is often selected as an ideal substitute of the traditional oil bearing by virtue of a series of advantages of small friction loss, good stability, small vibration and the like, and particularly has very wide application prospect in the fields of high-speed turbine, precision machine tool manufacturing and space technology.

Disclosure of Invention

The inventor researches and discovers that both the dynamic pressure gas bearing and the static pressure gas bearing in the related art have certain limitations. The static pressure gas bearing provides gas with certain pressure through an external gas supply system, then the gas is transmitted to a gap between the bearing and the rotor through a throttling structure, and then a gas film is formed in a matching gap between the rotor and the bearing to play a role in supporting the rotor. However, when the rotor speed is high, the static pressure gas bearing cannot effectively absorb and suppress the vibration of the rotor due to the lack of a damping mechanism, so that the stability of the bearing is reduced, and the use of the static pressure gas bearing in a high-speed and high-linear-speed working environment is limited.

The dynamic pressure gas bearing utilizes the wedge-shaped space formed between the rotor and the bearing surface to generate the wedge-shaped effect, and the ambient gas is continuously dragged into the wedge-shaped space due to the viscosity of the gas along with the continuous increase of the speed of the rotor, so that the air pressure in the wedge-shaped space is continuously increased. The dynamic pressure air film can be formed when the rotating speed of the bearing reaches a certain value. However, in the process of starting and stopping the rotor, due to insufficient rotating speed, an effective lubricating gas film cannot be formed between the dynamic pressure gas bearing and the rotor, so that serious dry friction exists between a top foil of the bearing and the surface of the rotor, the surface of the bearing is gradually seriously abraded under the action of the dry friction, the service life of the dynamic pressure gas bearing is influenced, and the situation that the foil and the rotor are seriously adhered and abraded in the later abrasion stage can even occur.

In addition, for the dynamic pressure foil bearing, under some complex and severe working conditions, such as an aircraft air conditioner compressor and a vehicle-mounted oilless air compressor, due to the impact of the ultra-large gravity acceleration in the acceleration process of the aircraft and the instantaneous large acceleration caused by the change along with road conditions in the running process of an automobile, the force which is several times or even tens of times of the gravity of the rotor is generated between the rotor and the dynamic pressure foil bearing, so that the wave foil of the dynamic pressure foil bearing is subjected to severe plastic deformation, the fit clearance between the rotor and the bearing is changed, and the gas bearing cannot form an effective gas film in the running process directly, so that the bearing fails to work.

In view of this, the embodiments of the present disclosure provide a gas bearing and a compressor, which can provide good support for a rotor with a larger rotation speed range, and can meet the working requirement of severe working conditions.

In one aspect of the present disclosure, there is provided a gas bearing including:

the bearing comprises a bearing shell, a bearing sleeve and a bearing sleeve, wherein the bearing shell is provided with an inner cavity extending along the axial direction, and the inner cavity comprises at least one static pressure mounting section and at least one dynamic pressure mounting section which are arranged along the axial direction;

at least one porous material inner shaft sleeve respectively arranged in the at least one static pressure mounting section;

at least one elastic material layer respectively arranged in the at least one dynamic pressure mounting section; and

at least one top foil arranged inside the at least one layer of elastomeric material, respectively,

wherein an inner diameter d2 of the at least one inner sleeve of porous material is smaller than an inner diameter d1 of the at least one top foil.

In some embodiments, the at least one elastomeric layer has a thickness of 1.5 to 2.5 mm.

In some embodiments, the material of the elastic material layer comprises modified ethylene propylene rubber having a peak elastic deformation of not more than 0.5%.

In some embodiments, the at least one top foil comprises a plurality of top foils, the at least one layer of resilient material comprises a plurality of layers of resilient material in one-to-one correspondence with the plurality of top foils, and each top foil is located inside and in surface contact with the inside of a corresponding layer of resilient material.

In some embodiments, the free end of each top foil overlaps the inner side surface of an adjacent top foil by an angular difference θ of 8 ° to 10 ° from the fixed end of said adjacent top foil.

In some embodiments, the at least one static pressure mounting section comprises at least two static pressure mounting sections, a portion of the at least two static pressure mounting sections being located axially on one side of the at least one dynamic pressure mounting section and another portion of the at least two static pressure mounting sections being located axially on the other side of the at least one dynamic pressure mounting section.

In some embodiments, the at least one inner sleeve of porous material comprises at least two inner sleeves of porous material respectively disposed within the at least two static pressure mounting sections, the at least two static pressure mounting sections are identical in structure and size, and the at least two inner sleeves of porous material are identical in structure and size.

In some embodiments, the at least one static pressure mounting section comprises two static pressure mounting sections and the at least one dynamic pressure mounting section comprises one dynamic pressure mounting section, the one dynamic pressure mounting section being axially located between the two static pressure mounting sections.

In some embodiments, the difference between the inner diameter d1 of the at least one top foil and the inner diameter d2 of the at least one porous material inner sleeve is 7-10 μm.

In some embodiments, the outer wall of the bearing shell has at least one first annular groove and an air supply inlet hole, each static pressure mounting section of the bearing shell has an air supply outlet hole, the body of the bearing shell has an air supply flow passage communicating the air supply inlet hole and the air supply outlet hole, and the at least one first annular groove is configured as an annular seal ring fixedly sleeved in the first annular groove.

In some embodiments, the outer circumferential surface of the porous material inner sleeve has a plurality of air flow grooves arranged at intervals in the axial direction, a flow opening is provided between adjacent air flow grooves, and the air supply outlet hole faces at least one of the air flow grooves.

In some embodiments, at least one of the plurality of air flow slots has a depth of 0.3 to 0.5 mm.

In some embodiments, the width of the vent is the same as the width of each of the plurality of airflow slots.

In some embodiments, the gas supply channel is a straight line channel penetrating through the body of the bearing housing, the gas supply channel is parallel to the axis of the bearing housing, and sealing plugs are arranged at both ends of the gas supply channel.

In one aspect of the present disclosure, there is provided a compressor comprising the aforementioned gas bearing.

Therefore, according to the embodiment of the disclosure, the inner shaft sleeve made of the porous material is arranged at the static pressure mounting section of the inner cavity of the bearing shell, the elastic material layer and the top foil are arranged at the dynamic pressure mounting section, and the inner diameter of the inner shaft sleeve made of the porous material is smaller than that of the top foil. On one hand, the gas bearing disclosed by the embodiment of the disclosure can realize reliable supporting effect on the rotor through the static pressure radial bearing section corresponding to the porous material inner shaft sleeve when the rotor is at a lower speed, and can provide supporting effect with higher rigidity and damping for the rotor through the elastic material layer and the top foil when the rotor is at a higher speed, so that the gas bearing disclosed by the embodiment of the disclosure can provide good support for the rotor in a larger rotating speed range, and the service life and the working stability are improved; on the other hand, excellent rigidity and damping are realized through the radial extrusion force and the circumferential friction force between the elastic material layer and the top foil, so that the self-excited vibration generated in the high-speed running process of the rotor is effectively prevented, and meanwhile, the influence of huge impact and a strong gravity field can be remarkably resisted, and the reliability of the rotor is remarkably improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure.

The present disclosure may be more clearly understood from the following detailed description, taken with reference to the accompanying drawings, in which:

FIG. 1 is a schematic structural view of some embodiments of a gas bearing according to the present disclosure;

FIG. 2 is a schematic structural view of a gas bearing according to some embodiments of the present disclosure from an axial perspective;

FIG. 3 is a schematic cross-sectional AA view of FIG. 2;

FIG. 4 is a schematic longitudinal cross-sectional view of an exploded structure in an axial direction according to some embodiments of the gas bearing of the present disclosure;

FIG. 5 is an enlarged schematic view of circle B in FIG. 2;

FIG. 6 is a perspective view of an inner sleeve of porous material in accordance with some embodiments of the gas bearing of the present disclosure.

It should be understood that the dimensions of the various parts shown in the figures are not drawn to scale. Further, the same or similar reference numerals denote the same or similar components.

Detailed Description

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the disclosure, its application, or uses. The present disclosure may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that: the relative arrangement of parts and steps, the composition of materials, numerical expressions and numerical values set forth in these embodiments are to be construed as merely illustrative, and not as limitative, unless specifically stated otherwise.

The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element preceding the word covers the element listed after the word, and does not exclude the possibility that other elements are also covered. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

In the present disclosure, when a specific device is described as being located between a first device and a second device, there may or may not be intervening devices between the specific device and the first device or the second device. When a particular device is described as being coupled to other devices, that particular device may be directly coupled to the other devices without intervening devices or may be directly coupled to the other devices with intervening devices.

All terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs unless specifically defined otherwise. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

FIG. 1 is a schematic structural view of some embodiments of a gas bearing according to the present disclosure. FIG. 2 is a schematic structural view of a gas bearing from an axial perspective according to some embodiments of the present disclosure. Fig. 3 is a schematic AA cross-sectional view of fig. 2. FIG. 4 is a schematic longitudinal cross-sectional view of an exploded structure in an axial direction according to some embodiments of the gas bearing of the present disclosure. Fig. 5 is an enlarged schematic view of circle B in fig. 2.

Referring to fig. 1-5, in some embodiments, a gas bearing includes: a bearing housing 10, at least one inner sleeve 20 of porous material, at least one layer of elastomeric material 30 and at least one top foil 40. The bearing housing 10 has an axially extending inner cavity comprising at least one static pressure mounting section 11b and at least one dynamic pressure mounting section 11a arranged in the axial direction.

At least one inner sleeve 20 of porous material is respectively arranged in the at least one static pressure mounting section 11 b. At least one elastic material layer 30 respectively disposed in the at least one dynamic pressure mounting section 11 a. At least one top foil 40, respectively, arranged inside said at least one layer of elastomeric material 30.

The embodiment realizes excellent rigidity and damping through the radial extrusion force and the circumferential friction force between the elastic material layer and the top foil, thereby effectively preventing the self-excited vibration generated by the rotor in the high-speed operation process, and simultaneously being capable of obviously resisting the influence of huge impact and a strong gravity field, and obviously improving the reliability of the rotor. Compared with the risk that permanent plastic deformation possibly occurs to cause failure in the related technology when the wave foil is adopted under a huge impact or strong gravity field, the wave foil is still elastically deformed even if the wave foil is subjected to huge impact or works under the strong gravity field in the working process, and therefore the working stability is greatly improved.

Referring to FIG. 3, the inner diameter d2 of the at least one inner sleeve 20 of porous material is smaller than the inner diameter d1 of the at least one top foil 40. Compared with the dynamic pressure radial bearing in the related technology, the dynamic pressure radial bearing can avoid serious dry friction between the dynamic pressure radial bearing section and the surface of the rotor in the low-speed stage of the rotor. And moreover, the matched structure of the elastic material layer and the top foil can support the rotor with higher rigidity and damping in the high-speed stage of the rotor, and compared with the static pressure radial bearing in the related art, the stability problem of the static pressure radial bearing section in the high-speed stage of the rotor can be avoided. Therefore, the suspension of the rotor in the full-speed working range can be further realized, and the service life of the gas bearing and the working stability and reliability are greatly prolonged.

In other words, by setting the inner diameter d2 of the inner sleeve 30 made of porous material to be smaller than the inner diameter d1 of the top foil 40, the action sequence of the static pressure radial bearing section corresponding to the inner sleeve made of porous material and the dynamic pressure radial bearing section corresponding to the top foil at different rotating speeds of the rotor can be realized, so that the performance of the dynamic pressure radial bearing and the static pressure radial bearing under different rotating speed conditions of the rotor can be fully realized, and the short plates of the static pressure radial bearing and the static pressure radial bearing in the related art can be better compensated.

In some embodiments, the at least one static mount section 11b comprises at least two static mount sections 11 b. A portion of the at least two static pressure mounting sections 11b is located on one side of the at least one dynamic pressure mounting section 11a in the axial direction, and another portion of the at least two static pressure mounting sections 11b is located on the other side of the at least one dynamic pressure mounting section 11a in the axial direction. The arrangement mode facilitates the assembly of the elastic material layer, the top foil and the porous material inner shaft sleeve in the inner cavity of the bearing shell, reduces the assembly difficulty and is easy to ensure the bearing precision.

It should be noted that two adjacent dynamic pressure foil sets may also be regarded as one dynamic pressure foil set that is longer in the axial direction, and two adjacent porous material inner sleeves may also be regarded as one porous material inner sleeve that is longer in the axial direction. Thus, the above arrangement can be regarded as a gas bearing having a combination of static pressure-dynamic pressure-static pressure. In other embodiments, the gas bearing may also adopt a combination of dynamic pressure-static pressure, a combination of dynamic pressure-static pressure-dynamic pressure, and the like. The gas bearing based on the static pressure-dynamic pressure-static pressure combination mode of the integrated bearing shell has the advantages of lower assembly difficulty, more compact structure and easier guarantee of precision.

Referring to fig. 3 and 4, in some embodiments, the at least one inner sleeve 30 of porous material comprises at least two inner sleeves 30 of porous material disposed within the at least two static pressure mounting sections 11b, respectively. The structure and the size of the at least two static pressure mounting sections 11b are the same, and the structure and the size of the at least two inner shaft sleeves 30 made of porous materials are the same. The structure can balance the stress of the gas bearing to obtain better working stability.

In fig. 3 and 4, the at least one static pressure mounting section 11b includes two static pressure mounting sections 11b, and the at least one dynamic pressure mounting section 11a includes one dynamic pressure mounting section 11a, and the one dynamic pressure mounting section 11a is located between the two static pressure mounting sections 11b in the axial direction. The gas bearing has high structural working stability, and the assembly can be simplified due to the small number of stages. And, this kind of gas bearing section number is less for whole axial width is relatively less, thereby guarantees the assembly precision more easily and is difficult to be worn and torn.

In the above embodiment, the difference between the inner diameter d1 of the at least one top foil 40 and the inner diameter d2 of the at least one inner sleeve 30 made of porous material is preferably 7-10 μm. The value range can enable the dynamic pressure radial bearing section corresponding to the top foil to obtain a relatively proper air film thickness, so that on one hand, the abrasion risk of the rotor and the dynamic pressure radial bearing section can be reduced, and on the other hand, the risk of instability caused by vibration of the dynamic pressure radial bearing section when the rotor rotates at a high speed is reduced.

Referring to FIGS. 2 and 5, in some embodiments, the at least one elastomeric layer 30 has a thickness of 1.5-2.5 mm. The value range can enable the dynamic pressure radial bearing section to obtain proper air film thickness, on one hand, a good buffering effect can be provided, the processing difficulty is reduced, and on the other hand, the deformation is controlled through proper thickness so as to meet the requirement of bearing capacity of the bearing.

As can be seen in fig. 5, the layer of resilient material 30 may be secured to the inner wall of the bearing housing 10 by means of an adhesive layer 33. The material of the elastic material layer 30 may include a polymer elastic material, such as modified ethylene propylene rubber with a peak elastic deformation of not more than 0.5%, so as to satisfy the requirements of both hardness and deformation while satisfying excellent elasticity.

In some embodiments, the at least one top foil 40 comprises a plurality of top foils 40, and the at least one resilient material layer 30 comprises a plurality of resilient material layers 30 in one-to-one correspondence with the plurality of top foils 40. Each top foil 40 is located inside a corresponding elastomeric layer 30 and is in surface contact with the inside surface of the corresponding elastomeric layer 30. In fig. 2 and 5, three top foils 40 form a three-segment lap joint structure with three layers of elastomeric material 30. The three top foils are installed in the same direction, and the fixed ends of the top foils are inserted into the fixed wire grooves in the inner wall of the bearing shell and are fixed by the fixed blocks. The fixing mode generates self-pre-tightening by bending back tension of the top foil of the foils, so that pre-tightening effect is generated among the foils.

Referring to fig. 5, in some embodiments, the free end of each top foil overlaps the inside surface of an adjacent top foil by an angular difference θ of 8 ° to 10 ° from the fixed end of the adjacent top foil. In fig. 5, the plurality of elastomeric layers 30 includes a first elastomeric layer 31 and a second elastomeric layer 32. The plurality of top foils 40 comprises a first top foil 41 and a second top foil 42.

The first elastomeric layer 31 is circumferentially adjacent to the second elastomeric layer 32, as are the respective first and second top foils 41, 42. The fixed end 42b of the second top foil 42 is inserted into the fixing line slot on the inner wall of the bearing housing and fixed by the fixing block 43, and the free end extends along the counterclockwise circumferential direction. The free end of the first top foil 41 also extends in the counterclockwise circumferential direction and overlaps the inner side surface of the second top foil 42. The angular difference θ between the lap joint position 41a and the fixed end 42b of the second top foil 42 is 8 ° to 10 °. This angular difference facilitates both the formation of a wedge-shaped gas film and minimizes or avoids excessive wear on the free end of the top foil.

Referring to fig. 3 and 4, in some embodiments, the outer wall of the bearing housing 10 has at least one first annular groove 12 and an air supply inlet hole 13, each static pressure mounting section 11b of the bearing housing 10 has an air supply outlet hole 15, the body of the bearing housing 10 has an air supply flow passage 14 communicating the air supply inlet hole 13 and the air supply outlet hole 15, and the at least one first annular groove 12 is configured as an annular seal ring fixedly disposed in the first annular groove 12. These first annular grooves 12 increase the damping of the gas bearing and may act as gas seals by means of the annular sealing rings. In some embodiments, the material of the bearing shell 10 comprises a relatively lightweight aluminum alloy material.

The inner sleeve 20 of porous material is located radially inside the static pressure mounting section 11b of the bearing housing 10. An external gas source can introduce high-pressure gas from the outside of the bearing housing 10 to the outside of the porous material inner sleeve 20 through the gas supply inlet holes 13 via the gas supply flow passage 14 and the gas supply outlet holes 15, and make the gas film uniformly act on the rotor inside the porous material inner sleeve 20 through the porous material. In some embodiments, the porous material comprises porous graphite.

In fig. 3 and 4, the air supply channel 14 is a straight channel penetrating through the body of the bearing housing 10, the air supply channel 14 is parallel to the axis of the bearing housing 10, and both ends of the air supply channel 14 are provided with sealing plugs 16. The air channel structure of the bearing shell 10 is more convenient to process.

The at least one first annular groove 12 includes a plurality of first annular grooves 12 arranged at intervals in the axial direction. A part and another part of the plurality of first annular grooves 12 are respectively located on both sides of the air supply inlet hole 13 in the axial direction. For example, two first annular grooves 12 may be provided on both sides of the gas feed hole 13 in the axial direction of the gas bearing, so that the gas bearing can be kept uniform in damping in the axial direction while improving the gas-tight effect.

FIG. 6 is a perspective view of an inner sleeve of porous material in accordance with some embodiments of the gas bearing of the present disclosure. Referring to fig. 4 and 6, in some embodiments, the outer circumferential surface of the inner sleeve 20 of porous material has a plurality of air flow grooves 21, the plurality of air flow grooves 21 are arranged at intervals in the axial direction, a flow opening 22 is provided between adjacent air flow grooves 21, and the air supply hole 15 faces at least one of the plurality of air flow grooves 21. These air flow grooves 21 may form a plurality of air flow passages with the bearing housing 10 so that high-pressure air can be uniformly discharged along the inner surface of the porous material inner sleeve 20, thereby providing a more uniform supporting function to the rotor.

In fig. 6, the width of the flow opening 22 is the same as the width of each of the plurality of gas flow grooves 21, so that the high-pressure gas is more uniformly distributed. In addition, the depth of at least one of the airflow grooves 21 is 0.3-0.5 mm.

Any of the embodiments of the gas bearing of the present disclosure described above may be used in various types of apparatuses that use rotors, such as compressors. Accordingly, embodiments of the present disclosure provide a compressor including any one of the gas bearings described above.

Thus, various embodiments of the present disclosure have been described in detail. Some details that are well known in the art have not been described in order to avoid obscuring the concepts of the present disclosure. It will be fully apparent to those skilled in the art from the foregoing description how to practice the presently disclosed embodiments.

Although some specific embodiments of the present disclosure have been described in detail by way of example, it should be understood by those skilled in the art that the foregoing examples are for purposes of illustration only and are not intended to limit the scope of the present disclosure. It will be understood by those skilled in the art that various changes may be made in the above embodiments or equivalents may be substituted for elements thereof without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A gas bearing, comprising:

a bearing housing (10) having an axially extending inner cavity comprising at least one static pressure mounting section (11b) and at least one dynamic pressure mounting section (11a) arranged in an axial direction;

at least one porous material inner sleeve (20) respectively arranged in the at least one static pressure mounting section (11 b);

at least one elastic material layer (30) respectively disposed in the at least one dynamic pressure mounting section (11 a); and

at least one top foil (40) respectively arranged inside the at least one layer of elastomeric material (30),

wherein the inner diameter d2 of the at least one inner sleeve (20) of porous material is smaller than the inner diameter d1 of the at least one top foil (40).

2. A gas bearing according to claim 1, wherein the at least one layer (30) of elastomeric material has a thickness of 1.5-2.5 mm.

3. Gas bearing according to claim 1, wherein the at least one top foil (40) comprises a plurality of top foils (40), wherein the at least one layer of resilient material (30) comprises a plurality of layers of resilient material (30) in one-to-one correspondence with the plurality of top foils (40), wherein each top foil (40) is located inside the corresponding layer of resilient material (30) and is in surface contact with the inside of the corresponding layer of resilient material (30).

4. A gas bearing according to claim 3, wherein the free end (41a) of each top foil (40) overlaps the inner side surface of the adjacent top foil (40) by an angular difference θ of 8 ° to 10 ° from the fixed end (42b) of the adjacent top foil (40).

5. The gas bearing according to claim 1, wherein the at least one static pressure mounting section (11b) comprises at least two static pressure mounting sections (11b), a portion of the at least two static pressure mounting sections (11b) being located axially on one side of the at least one dynamic pressure mounting section (11a) and another portion of the at least two static pressure mounting sections (11b) being located axially on the other side of the at least one dynamic pressure mounting section (11 a).

6. The gas bearing of claim 5, wherein said at least one porous material inner sleeve (20) comprises at least two porous material inner sleeves (20) disposed within said at least two static pressure mounting sections (11b), respectively, said at least two static pressure mounting sections (11b) being identical in structure and size, said at least two porous material inner sleeves (20) being identical in structure and size.

7. A gas bearing according to claim 1, wherein the at least one static pressure mounting section (11b) comprises two static pressure mounting sections (11b) and the at least one dynamic pressure mounting section (11a) comprises one dynamic pressure mounting section (11a), the one dynamic pressure mounting section (11a) being axially located between the two static pressure mounting sections (11 b).

8. Gas bearing according to claim 1, wherein the difference between the inner diameter d1 of the at least one top foil (40) and the inner diameter d2 of the at least one porous material inner sleeve (20) is 7-10 μm.

9. The gas bearing according to claim 1, characterized in that the outer wall of the bearing housing (10) has at least one first annular groove (12) and a gas supply inlet hole (13), each static pressure mounting section (11b) of the bearing housing (10) has a gas supply outlet hole (15), the body of the bearing housing (10) has a gas supply flow channel (14) communicating the gas supply inlet hole (13) and the gas supply outlet hole (15), the at least one first annular groove (12) is configured as an annular sealing ring fixedly fitted in the first annular groove (12).

10. The gas bearing according to claim 9, wherein the outer peripheral surface of the inner sleeve (20) of porous material has a plurality of gas flow grooves (21), the plurality of gas flow grooves (21) are arranged at intervals in the axial direction, flow openings (22) are provided between adjacent gas flow grooves (21), and the gas supply outlet hole (15) faces at least one of the plurality of gas flow grooves (21).

11. The gas bearing according to claim 10, wherein at least one of the plurality of gas flow grooves (21) has a depth of 0.3 to 0.5 mm.

12. The gas bearing of claim 10, wherein the width of the flow opening (22) is the same as the width of each of the plurality of gas flow slots (21).

13. The gas bearing according to claim 9, characterized in that the gas supply channel (14) is a straight channel running through the body of the bearing housing (10), the gas supply channel (14) is parallel to the axis of the bearing housing (10), and sealing plugs (16) are provided at both ends of the gas supply channel (14).

14. A compressor, comprising:

a gas bearing according to any one of claims 1 to 13.