Gas bearings and compressors

Abstract

The present disclosure relates to a gas bearing and a compressor. The gas bearing comprises: a bearing shell (10), having an inner cavity extending in an axial direction, the 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 (30), respectively arranged in the at least one static pressure mounting section (11b); and at least one dynamic pressure foil group (20), respectively arranged in the at least one dynamic pressure mounting section (11a), wherein the inner diameter d2 of the at least one porous material inner sleeve (30) is smaller than the inner diameter d1 of the at least one dynamic pressure foil group (20). The embodiments of the present disclosure can provide good support for rotors with a larger speed range, thereby improving service life and working stability.

Description

Technical Field

[0001] The present disclosure relates to the field of bearings, and in particular to a gas bearing and a compressor. Background Art

[0002] Gas bearings are a type of bearing that uses gas as a lubricating medium and utilizes the dynamic pressure effect or static pressure effect of the gas fluid to form a lubricating gas film that supports the load. In related technologies, gas bearings can be divided into dynamic pressure gas bearings, static pressure gas bearings, and extrusion gas bearings according to the different mechanisms of lubricating gas film generation. Gas bearings are often selected as an ideal replacement for traditional oil bearings due to their advantages such as low friction loss, good stability, and low vibration. Especially in the fields of high-speed turbines, precision machine tool manufacturing, and space technology, gas bearings have very broad application prospects. Summary of the invention

[0003] The inventors have found that both the hydrodynamic gas bearings and the static gas bearings in the related art have certain limitations. The hydrodynamic gas bearing uses the wedge-shaped space formed between the rotor and the bearing surface to produce a wedge effect. As the rotor speed continues to increase, the surrounding gas is continuously dragged into the wedge-shaped space due to the viscosity of the gas, resulting in a continuous increase in the air pressure in the wedge-shaped space. The hydrodynamic gas film can only be formed when the bearing speed reaches a certain value. However, during the start-up and stop of the rotor, due to insufficient speed, an effective lubricating gas film cannot be formed between the hydrodynamic gas bearing and the rotor, resulting in severe dry friction between the top foil of the bearing and the surface of the rotor, causing the bearing surface to gradually suffer severe wear under the action of dry friction, thereby affecting the service life of the hydrodynamic gas bearing. In the later stage of wear, there may even be severe adhesive wear between the foil and the rotor.

[0004] The hydrostatic gas bearing provides gas of a certain pressure through an external gas supply system, and then the gas is transmitted to the gap between the bearing and the rotor through the throttling structure, and then forms an air film in the matching gap between the rotor and the bearing to support the rotor. However, when the rotor speed is high, the hydrostatic gas bearing cannot effectively absorb and suppress the vibration of the rotor due to the lack of a damping mechanism, resulting in reduced bearing stability, which limits the use of hydrostatic gas bearings in high-speed and high-line speed working environments.

[0005] 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 in a larger speed range, thereby improving service life and working stability.

[0006] In one aspect of the present disclosure, there is provided a gas bearing, comprising:

[0007] The bearing shell has an inner cavity extending in the axial direction, wherein the inner cavity includes at least one static pressure installation section and at least one dynamic pressure installation section arranged in the axial direction;

[0008] at least one inner sleeve made of porous material, respectively disposed in the at least one static pressure mounting section;

[0009] At least one dynamic pressure foil group is respectively arranged in the at least one dynamic pressure installation section,

[0010] The inner diameter d2 of the at least one porous material inner sleeve is smaller than the inner diameter d1 of the at least one dynamic pressure foil group.

[0011] In some embodiments, the at least one static pressure mounting segment includes at least two static pressure mounting segments, a portion of the at least two static pressure mounting segments is axially located on one side of the at least one dynamic pressure mounting segment, and another portion of the at least two static pressure mounting segments is axially located on the other side of the at least one dynamic pressure mounting segment.

[0012] In some embodiments, the at least one porous material inner sleeve includes at least two porous material inner sleeves, which are respectively arranged in the at least two static pressure mounting sections, and the at least two static pressure mounting sections have the same structure and size, and the at least two porous material inner sleeves have the same structure and size.

[0013] In some embodiments, the at least one porous material inner sleeve includes two porous material inner sleeves, and the at least one dynamic pressure foil group includes one dynamic pressure foil group, and the one dynamic pressure foil group is located between the two porous material inner sleeves.

[0014] In some embodiments, the difference between the inner diameter of the at least one dynamic pressure foil group and the inner diameter of the at least one porous material inner sleeve is 5-8 μm.

[0015] In some embodiments, the dynamic pressure foil group includes:

[0016] A plurality of support corrugated foils are connected to the inner wall of the dynamic pressure mounting section of the bearing housing, each support corrugated foil is in an arc shape as a whole, and has a plurality of arc-shaped corrugations along the extension direction of the support corrugated foil;

[0017] A first top foil connected to the inner wall of the dynamic pressure mounting section of the bearing housing, the first top foil being located on a side of the supporting bump foil adjacent to the axis of the bearing housing and supporting the supporting bump foil in a radial direction;

[0018] a second top foil connected to the inner wall of the dynamic pressure mounting section of the bearing housing, the second top foil being located on a side of the first top foil adjacent to the axis of the bearing housing and supporting the first top foil in a radial direction,

[0019] The inner diameter d1 of the dynamic pressure foil group is the inner diameter of the second top foil.

[0020] In some embodiments, the inner wall of the dynamic pressure mounting section of the bearing shell has multiple groups of wire grooves corresponding to the multiple support wave foils, the first end of the support wave foil corresponding to each group of wire grooves is fixed in the group of wire grooves, the first end of the first top foil is fixed in a group of wire grooves among the multiple groups of wire grooves, the first end of the second top foil is fixed in a group of wire grooves among the multiple groups of wire grooves, the extension direction of the second end of the support wave foil corresponding to each group of wire grooves relative to the first end is opposite to the extension direction of the second end of the first top foil relative to the first end, and the extension direction of the second end of the support wave foil corresponding to each group of wire grooves relative to the first end is the same as the extension direction of the second end of the second top foil relative to the first end.

[0021] In some embodiments, each group of wire slots includes non-pin hole wire slots, and the first end of the supporting wave foil corresponding to each group of wire slots is inserted and fixed in the non-pin hole wire slots. At least one group of wire slots among the multiple groups of wire slots includes a pin hole wire slot, and the first end of the first top foil and the first end of the second top foil are both inserted in the pin hole wire slot and fixed by a pin.

[0022] In some embodiments, the first end of the first top foil and the first end of the second top foil are both inserted into the same pin hole wire groove.

[0023] In some embodiments, a height h1 of at least one of the multiple arc-shaped corrugations of the supporting wave foil is 0.4 to 0.6 mm, and / or a diameter d3 of at least one of the multiple arc-shaped corrugations of the supporting wave foil is 4 to 5 mm, and / or an angle difference α between every two adjacent arc-shaped corrugations of the multiple corrugations of the supporting wave foil relative to the axis of the bearing shell is 3° to 5°.

[0024] In some embodiments, the outer wall of the bearing shell has at least one first annular groove and an air inlet hole, each static pressure mounting section of the bearing shell has an air outlet hole, the body of the bearing shell has an air supply flow channel connecting the air inlet hole and the air outlet hole, and the at least one first annular groove is configured as an annular sealing ring fixedly mounted in the first annular groove.

[0025] In some embodiments, the outer peripheral surface of the porous material inner sleeve has a plurality of airflow grooves, the plurality of airflow grooves are arranged at intervals along the axial direction, flow openings are provided between adjacent airflow grooves, and the air supply outlet is directly opposite to at least one of the plurality of airflow grooves.

[0026] In some embodiments, a depth of at least one of the plurality of air flow grooves is 0.3-0.5 mm.

[0027] In some embodiments, the width of the through-flow opening is the same as the width of each of the plurality of air flow slots.

[0028] In some embodiments, the air supply channel is a straight channel that passes through the body of the bearing shell, the air supply channel is parallel to the axis of the bearing shell, and sealing screw plugs are provided at both ends of the air supply channel.

[0029] In one aspect of the present disclosure, a compressor is provided, comprising the aforementioned gas bearing.

[0030] Therefore, according to the embodiment of the present disclosure, at least one porous material inner sleeve and at least one dynamic pressure foil group are respectively arranged in at least one static pressure installation section and at least one dynamic pressure installation section arranged axially in the inner cavity of the bearing shell, and the inner diameter of the porous material inner sleeve is smaller than the inner diameter of the dynamic pressure foil group. This enables the gas bearing of the embodiment of the present disclosure to achieve reliable support for the rotor through the static pressure radial bearing section corresponding to the porous material inner sleeve when the rotor is at a lower speed, and to provide support with higher stiffness and damping to the rotor through the dynamic pressure radial bearing section corresponding to the dynamic pressure foil group when the rotor is at a higher speed, so that the gas bearing of the embodiment of the present disclosure can provide good support for the rotor in a wider speed range, and improve the service life and working stability.

[0031] In addition, the integrated bearing shell makes it easier to ensure the coaxiality of the gas bearing during processing, thereby ensuring the bearing installation accuracy, thereby improving the quality of the air film formed by the gas bearing, and on the other hand, also obtaining higher structural strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings, which constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0033] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0034] Figure 1 is a schematic structural diagram of some embodiments of the gas bearing according to the present disclosure;

[0035] Figure 2 is a schematic longitudinal cross-sectional view of the mounting structure of some embodiments of the gas bearing according to the present disclosure along the axial direction;

[0036] Figure 3 is a schematic longitudinal cross-sectional view of an exploded structure along the axial direction of some embodiments of the gas bearing disclosed herein;

[0037] Figure 4 is a schematic structural diagram of a hydrodynamic bearing segment in an axial perspective according to some embodiments of the gas bearing disclosed herein;

[0038] Figure 5 yes Figure 4 An enlarged schematic diagram of the middle circle A;

[0039] Figure 6 It is a schematic diagram of the three-dimensional structure of the inner sleeve of the porous material in some embodiments of the gas bearing disclosed in the present invention.

[0040] It should be understood that the size of each part shown in the accompanying drawings is not drawn according to the actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. DETAILED DESCRIPTION

[0041] 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 present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the components and steps, the composition of the materials, the numerical expressions and the numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary and not as limiting.

[0042] The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. The words "include" or "comprise" and similar words mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of including other elements. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0043] 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 an intermediate device between the specific device and the first device or the second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other device without an intermediate device, or may not be directly connected to the other device but have an intermediate device.

[0044] All terms (including technical terms or scientific terms) used in the present disclosure have the same meanings as those understood by ordinary technicians in the field to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, such as general dictionaries, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined herein.

[0045] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0046] Figure 1 Schematic diagram of the structure of some embodiments of the gas bearing according to the present disclosure. Figure 2 It is a schematic longitudinal cross-sectional view along the axial direction of the mounting structure of some embodiments of the gas bearing according to the present disclosure. Figure 3 1 is a schematic longitudinal cross-sectional view of an exploded structure of some embodiments of a gas bearing according to the present disclosure along the axial direction.

[0047] refer to Figure 1-Figure 3 In some embodiments, the gas bearing comprises: a bearing shell 10, at least one porous material inner sleeve 30 and at least one dynamic pressure foil group 20. The bearing shell 10 has an inner cavity extending in the axial direction, and the inner cavity comprises at least one static pressure installation section 11b and at least one dynamic pressure installation section 11a arranged in the axial direction. At least one porous material inner sleeve 30 is respectively arranged in the at least one static pressure installation section 11b. At least one dynamic pressure foil group 20 is respectively arranged in the at least one dynamic pressure installation section 11a.

[0048] In this embodiment, at least one inner sleeve of a porous material and at least one dynamic pressure foil group are respectively arranged in at least one static pressure installation section and at least one dynamic pressure installation section arranged axially in the inner cavity of the bearing shell, so as to utilize the performance of the dynamic pressure radial bearing and the static pressure radial bearing under different rotation speed conditions of the rotor, respectively, to make up for the shortcomings of the static pressure radial bearing and the static pressure radial bearing in the related technology. The axial direction here refers to the direction parallel to the axis s of the gas bearing. In addition, the one-piece bearing shell can make it easier to ensure the coaxiality of the gas bearing during processing, thereby ensuring the bearing installation accuracy, thereby improving the quality of the air film formed by the gas bearing, and on the other hand, it can also obtain higher structural strength.

[0049] refer to Figure 2 , the inner diameter d2 of at least one porous material inner sleeve 30 is smaller than the inner diameter d1 of at least one dynamic pressure foil group 20. This design enables the porous material inner sleeve to support the rotor in the low-speed stage of the rotor, so that the rotor can float smoothly in the low-speed stage. Compared with the dynamic pressure radial bearing in the related art, it can avoid the serious dry friction between the dynamic pressure radial bearing section and the rotor surface in the low-speed stage of the rotor. In addition, it also enables the dynamic pressure foil group to support the rotor with higher stiffness and damping in the high-speed stage of the rotor. Compared with the static pressure radial bearing in the related art, it can avoid the stability problem of the static pressure radial bearing section in the high-speed stage of the rotor. In this way, the rotor can be further suspended in the full speed range of operation, thereby greatly extending the service life of the gas bearing and the working stability and reliability.

[0050] In other words, by setting the inner diameter d2 of the porous material inner sleeve 30 to be smaller than the inner diameter d1 of the dynamic pressure foil group 20, the action sequence of the static pressure radial bearing section corresponding to the porous material inner sleeve and the dynamic pressure radial bearing section corresponding to the dynamic pressure foil group under different rotor speeds can be achieved, thereby fully utilizing the performance of the dynamic pressure radial bearing and the static pressure radial bearing under different rotor speed conditions, and better compensating for the respective shortcomings of the static pressure radial bearing and the static pressure radial bearing in the related technology.

[0051] In some embodiments, at least one static pressure installation section 11b includes at least two static pressure installation sections 11b. A portion of the at least two static pressure installation sections 11b is axially located on one side of the at least one dynamic pressure installation section 11a, and another portion of the at least two static pressure installation sections 11b is axially located on the other side of the at least one dynamic pressure installation section 11a. This arrangement facilitates the assembly of the dynamic pressure foil group and the porous material inner sleeve in the inner cavity of the bearing shell, reduces the difficulty of assembly, and easily ensures the bearing accuracy.

[0052] It should be noted that two adjacent dynamic pressure foil groups can also be regarded as a dynamic pressure foil group that is longer in the axial direction, and two adjacent porous material inner sleeves can also be regarded as a porous material inner sleeve that is longer in the axial direction. In this way, the above arrangement can be regarded as a gas bearing with a combination of static pressure-dynamic pressure-static pressure. In other embodiments, the gas bearing can also adopt a combination of dynamic pressure-static pressure, or a combination of dynamic pressure-static pressure-dynamic pressure, etc. The gas bearing in this embodiment based on the static pressure-dynamic pressure-static pressure combination of the integrated bearing shell is easier to assemble, has a more compact structure, and is easier to ensure precision.

[0053] refer to Figure 2 and Figure 3 In some embodiments, the at least one porous material inner sleeve 30 includes at least two porous material inner sleeves 30, which are respectively arranged in the at least two static pressure installation sections 11b. The at least two static pressure installation sections 11b have the same structure and size, and the at least two porous material inner sleeves 30 have the same structure and size. This structure can balance the force of the gas bearing to obtain better working stability.

[0054] exist Figure 2 and Figure 3 In the embodiment, the at least one porous material inner sleeve 30 includes two porous material inner sleeves 30, and the at least one dynamic pressure foil group 20 includes one dynamic pressure foil group 20, and the one dynamic pressure foil group 20 is located between the two porous material inner sleeves 30. The structure of this gas bearing has high working stability, and the small number of sections can simplify assembly. In addition, the small number of sections of this gas bearing makes the overall axial width relatively small, so that it is easier to ensure assembly accuracy and is not easy to be worn.

[0055] In the above embodiment, the difference between the inner diameter of at least one dynamic pressure foil group 20 and the inner diameter of the at least one porous material inner sleeve 30 is preferably 5-8 μm. This value range enables the dynamic pressure radial bearing segment corresponding to the dynamic pressure foil group 20 to obtain a relatively suitable air film thickness, which can reduce the wear risk of the rotor and the dynamic pressure radial bearing segment on the one hand, and reduce the risk of instability caused by vibration of the dynamic pressure radial bearing segment when the rotor rotates at high speed on the other hand.

[0056] Figure 4 It is a schematic structural diagram of the hydrodynamic bearing segment in an axial perspective in some embodiments of the gas bearing disclosed herein. Figure 5 yes Figure 4 Enlarged diagram of the middle circle A. Figure 4 and Figure 5 In some embodiments, the dynamic pressure foil group 20 includes: a plurality of support bump foils 21, a first top foil 22, and a second top foil 23. The plurality of support bump foils 21 are connected to the inner wall of the dynamic pressure mounting section 11a of the bearing housing 10, and each support bump foil 21 is in an arc shape as a whole, and has a plurality of arc-shaped corrugations along the extension direction of the support bump foil 21. In some embodiments, the plurality of support bump foils 21 include three arc-shaped support bump foils 21 of substantially the same length.

[0057] refer to Figure 5 In some embodiments, the height h1 of at least one of the multiple arcuate corrugations of the support corrugated foil 22 is 0.4-0.6 mm. In some embodiments, the diameter d3 of at least one of the multiple arcuate corrugations of the support corrugated foil 22 is 4-5 mm. In some embodiments, the angle difference α between each two adjacent arcuate corrugations of the multiple arcuate corrugations of the support corrugated foil 22 relative to the axis of the first bearing sleeve 21 is 3°-5°.

[0058] The first top foil 22 is connected to the inner wall of the dynamic pressure installation section 11a of the bearing housing 10. The first top foil 22 is located on the side of the support bump foil 21 adjacent to the axis of the bearing housing 10 and supports the support bump foil 21 in the radial direction. The second top foil 23 is connected to the inner wall of the dynamic pressure installation section 11a of the bearing housing 10. The second top foil 23 is located on the side of the first top foil 22 adjacent to the axis of the bearing housing 10 and supports the first top foil 22 in the radial direction. In this embodiment, the inner diameter d1 of the dynamic pressure foil group 20 is the inner diameter of the second top foil 23.

[0059] In this embodiment, the dynamic pressure foil group 20 can obtain better stiffness and damping when the rotor is in high-speed conditions through the combined structure of the single wave foil and double top foil, so as to prevent the rotor from self-excited vibration, thereby effectively improving the working stability of the rotor under high-speed conditions.

[0060] exist Figure 2-Figure 4 In the embodiment, the inner wall of the dynamic pressure installation section 11a of the bearing housing 10 has a plurality of wire grooves corresponding to the plurality of support bump foils 21, and the first end of the support bump foil 21 corresponding to each wire groove is fixed in the wire groove. The first end of the first top foil 22 is fixed in one of the plurality of wire grooves, and the first end of the second top foil 23 is fixed in one of the plurality of wire grooves. The support bump foil 21, the first top foil 22, and the second top foil 23 can be connected to the interior of the bearing housing 10 through pin hole wire grooves or non-pin hole wire grooves, respectively.

[0061] The extension direction of the second end of the support bump foil 21 corresponding to each group of wire slots relative to the first end is opposite to the extension direction of the second end of the first top foil 22 relative to the first end, and the extension direction of the second end of the support bump foil 21 corresponding to each group of wire slots relative to the first end is the same as the extension direction of the second end of the second top foil 23 relative to the first end. Figure 5 In the embodiment, the extending direction of the supporting bump foil 21 is the clockwise direction, the extending direction of the first top foil 22 is the counterclockwise direction, and the extending direction of the second top foil 23 is the clockwise direction.

[0062] refer to Figure 5 In some embodiments, each group of wire slots includes a non-pin hole wire slot 17a, and the first end of the supporting corrugated foil 21 corresponding to each group of wire slots is inserted and fixed in the non-pin hole wire slot 17a. At least one group of wire slots in the plurality of groups of wire slots includes a pin hole wire slot 17b, and the first end of the first top foil 22 and the first end of the second top foil 23 are both inserted in the pin hole wire slot 17b and fixed by a pin. This fixing method generates a self-pretightening effect through the bending tension of the first top foil 22 and the second top foil 23, and generates a pretightening effect between the first top foil 22 and the supporting corrugated foil 21.

[0063] exist Figure 4 and Figure 5 In the embodiment, the first end of the first top foil 22 and the first end of the second top foil 23 are both inserted into the same pin hole wire groove 17b. In this way, the first top foil 22 and the second top foil 23 can be together surrounded by a closed ring, so as to form a reliable support for each supporting bump foil 21.

[0064] Figure 6 Schematic diagram of the three-dimensional structure of the porous material inner sleeve in some embodiments of the gas bearing disclosed in the present invention. Figure 2 , Figure 3 and Figure 6In some embodiments, the outer wall of the bearing housing 10 has at least one first annular groove 12 and an air supply inlet 13, each static pressure mounting section 11b of the bearing housing 10 has an air supply outlet 15, the body of the bearing housing 10 has an air supply flow passage 14 connecting the air supply inlet 13 and the air supply outlet 15, and the at least one first annular groove 12 is configured as an annular sealing ring fixedly sleeved in the first annular groove 12. These first annular grooves 12 can increase the damping of the gas bearing and can play an airtight role through the annular sealing ring. In some embodiments, the material of the bearing housing 10 includes a relatively lightweight aluminum alloy material.

[0065] The porous material inner sleeve 30 is located radially inside the static pressure installation section 11b of the bearing housing 10. An external gas source can pass high-pressure gas from the outside of the bearing housing 10 to the outside of the porous material inner sleeve 30 through the gas supply inlet hole 13 via the gas supply flow channel 14 and the gas supply outlet hole 15, and the porous material allows the gas film to evenly act on the rotor inside the porous material inner sleeve 30. In some embodiments, the porous material includes porous graphite.

[0066] refer to Figure 2 and Figure 3 The air supply passage 14 is a straight passage that runs through the body of the bearing housing 10, the air supply passage 14 is parallel to the axis of the bearing housing 10, and sealing screw plugs 16 are provided at both ends of the air supply passage 14. The air passage structure of the bearing housing 10 is more convenient to process and form.

[0067] exist Figure 6 In the embodiment, at least one first annular groove 12 includes a plurality of first annular grooves 12 spaced apart in the axial direction. A portion and another portion of the plurality of first annular grooves 12 are respectively located on both sides of the gas supply inlet hole 13 in the axial direction. For example, two first annular grooves 12 may be located on both sides of the gas supply inlet hole 13 in the axial direction of the gas bearing, thereby improving the airtight effect and keeping the damping of the gas bearing consistent in the axial direction.

[0068] refer to Figure 6 In some embodiments, the outer peripheral surface of the porous material inner sleeve 30 has a plurality of air flow grooves 31, the plurality of air flow grooves 31 are arranged at intervals along the axial direction, and a flow opening 32 is provided between adjacent air flow grooves 31, and the air supply outlet 15 is directly opposite to at least one of the plurality of air flow grooves 31. The air flow grooves 31 can form a plurality of air flow channels with the bearing housing 10, so that the high-pressure gas can be uniformly discharged along the inner surface of the porous material inner sleeve 30, thereby providing a more uniform support effect on the rotor.

[0069] exist Figure 6In the embodiment, the width of the through-flow opening 32 is the same as the width of each of the plurality of air flow grooves 31, so that the high pressure gas is more evenly distributed. In addition, the depth of at least one of the plurality of air flow grooves 31 is 0.3-0.5 mm.

[0070] Any of the above-mentioned gas bearings of the present disclosure can be used in various types of equipment using rotors, such as compressors. Therefore, an embodiment of the present disclosure provides a compressor, comprising any of the above-mentioned gas bearings.

[0071] So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.

[0072] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents 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, characterized in that: include: The bearing shell (10) has an inner cavity extending in the axial direction, wherein the inner cavity comprises at least one static pressure installation section (11b) and at least one dynamic pressure installation section (11a) arranged in the axial direction; At least one porous material inner sleeve (30) is respectively arranged in the at least one static pressure installation section (11b); At least one dynamic pressure foil group (20) is respectively arranged in the at least one dynamic pressure installation section (11a), The inner diameter d2 of the at least one porous material inner sleeve (30) is smaller than the inner diameter d1 of the at least one dynamic pressure foil group (20); the outer wall of the bearing shell (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 shell (10) has an air supply outlet hole (15); the body of the bearing shell (10) has an air supply flow channel (14) connecting the air supply inlet hole (13) and the air supply outlet hole (15); the at least one first annular groove (12) is The invention is configured as an annular sealing ring fixedly sleeved in the first annular groove (12); the outer peripheral surface of the porous material inner sleeve (30) has a plurality of air flow grooves (31), and the plurality of air flow grooves (31) are arranged at intervals along the axial direction to form a plurality of air flow channels between the bearing shell (10), so that high-pressure gas can be evenly discharged along the inner surface of the porous material inner sleeve (30), and a flow port (32) is provided between adjacent air flow grooves (31), and the air supply outlet (15) is directly opposite to at least one of the plurality of air flow grooves (31).

2. The gas bearing according to claim 1, characterized in that 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 axially located 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 axially located on the other side of the at least one dynamic pressure mounting section (11a).

3. The gas bearing according to claim 2, characterized in that: The at least one porous material inner shaft sleeve (30) comprises at least two porous material inner shaft sleeves (30), which are respectively arranged in the at least two static pressure installation sections (11b); the at least two static pressure installation sections (11b) have the same structure and size, and the at least two porous material inner shaft sleeves (30) have the same structure and size.

4. The gas bearing according to claim 1, characterized in that The at least one porous material inner sleeve (30) comprises two porous material inner sleeves (30), and the at least one dynamic pressure foil group (20) comprises one dynamic pressure foil group (20), wherein the one dynamic pressure foil group (20) is located between the two porous material inner sleeves (30).

5. The gas bearing according to claim 1, characterized in that The difference between the inner diameter of the at least one dynamic pressure foil group (20) and the inner diameter of the at least one porous material inner sleeve (30) is 5-8 μm.

6. The gas bearing according to claim 1, characterized in that The dynamic pressure foil group (20) comprises: A plurality of support corrugated foils (21) connected to the inner wall of the dynamic pressure mounting section (11a) of the bearing housing (10), each support corrugated foil (21) being in an arc shape as a whole and having a plurality of arc-shaped corrugations along the extension direction of the support corrugated foil (21); a first top foil (22) connected to the inner wall of the dynamic pressure mounting section (11a) of the bearing shell (10), the first top foil (22) being located on a side of the supporting corrugated foil (21) adjacent to the axis of the bearing shell (10) and supporting the supporting corrugated foil (21) in a radial direction; a second top foil (23) connected to the inner wall of the dynamic pressure mounting section (11a) of the bearing shell (10), the second top foil (23) being located on a side of the first top foil (22) adjacent to the axis of the bearing shell (10) and supporting the first top foil (22) in a radial direction, Wherein, the inner diameter d1 of the dynamic pressure foil group (20) is the inner diameter of the second top foil (23).

7. The gas bearing according to claim 6, characterized in that The inner wall of the dynamic pressure mounting section (11a) of the bearing housing (10) has a plurality of groups of wire grooves corresponding to the plurality of support corrugated foils (21); the first end of the support corrugated foil (21) corresponding to each group of wire grooves is fixed in the group of wire grooves; the first end of the first top foil (22) is fixed in a group of wire grooves among the plurality of groups of wire grooves; the first end of the second top foil (23) is fixed in a group of wire grooves among the plurality of groups of wire grooves; the extension direction of the second end of the support corrugated foil (21) corresponding to each group of wire grooves relative to the first end is opposite to the extension direction of the second end of the first top foil (22) relative to the first end; and the extension direction of the second end of the support corrugated foil (21) corresponding to each group of wire grooves relative to the first end is the same as the extension direction of the second end of the second top foil (23) relative to the first end.

8. The gas bearing according to claim 7, characterized in that Each group of wire troughs comprises a non-pin hole wire trough (17a), and the first end of the supporting corrugated foil (21) corresponding to each group of wire troughs is inserted and fixed in the non-pin hole wire trough (17a); at least one group of wire troughs among the plurality of groups of wire troughs comprises a pin hole wire trough (17b), and the first end of the first top foil (22) and the first end of the second top foil (23) are both inserted in the pin hole wire trough (17b) and fixed by a pin.

9. The gas bearing according to claim 8, characterized in that The first end of the first top foil (22) and the first end of the second top foil (23) are both plugged into the same pin hole wire groove (17b).

10. The gas bearing according to claim 6, characterized in that The height h1 of at least one of the multiple arc-shaped corrugations of the supporting corrugation foil (21) is 0.4-0.6 mm, and / or the diameter d3 of at least one of the multiple arc-shaped corrugations of the supporting corrugation foil (21) is 4-5 mm, and / or the angle difference α between every two adjacent arc-shaped corrugations of the multiple corrugations of the supporting corrugation foil (21) relative to the axis of the bearing shell (10) is 3°-5°.

11. The gas bearing according to claim 1, characterized in that The depth of at least one of the plurality of air flow grooves (31) is 0.3-0.5 mm.

12. The gas bearing according to claim 1, characterized in that The width of the flow opening (32) is the same as the width of each of the plurality of air flow grooves (31).

13. The gas bearing according to claim 1, characterized in that The air supply channel (14) is a straight channel that penetrates the body of the bearing shell (10); the air supply channel (14) is parallel to the axis of the bearing shell (10); and sealing screw plugs (16) are provided at both ends of the air supply channel (14).

14. A compressor, characterized in that: include: A gas bearing according to any one of claims 1 to 13.

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