Gas thrust bearings, bearing assemblies, compressors, air conditioners and automobiles

Abstract

The present disclosure relates to a gas thrust bearing, a bearing assembly, a compressor, an air conditioner and an automobile. The bearing assembly includes: a rotor having a thrust plate; a bearing housing located on one side of the thrust plate along the axial direction of the rotor; and a plurality of foil groups arranged along the circumferential direction of the bearing housing, wherein the foil group includes: a wave foil located on one side of the bearing housing adjacent to the thrust plate; and a top foil located on the side of the wave foil away from the bearing housing, wherein the top foil includes a first top foil segment and at least two second top foil segments, the first top foil segment is parallel to the surface of the thrust plate, and the at least two second top foil segments are inclined at an angle relative to the surface of the thrust plate; according to the rotation direction of the rotor during operation, the first top foil segment is located downstream of the at least two second top foil segments, and the inclination angle of the second top foil segment located upstream relative to the surface of the thrust plate is greater than the inclination angle of the second top foil segment located downstream relative to the surface of the thrust plate. The embodiment of the present disclosure can quickly form a stable dynamic pressure gas film.

Description

Technical Field

[0001] The present disclosure relates to the field of bearings, and in particular to a gas thrust bearing, a bearing assembly, a compressor, an air conditioner and an automobile. Background Art

[0002] Hydrogen fuel cell vehicles are a strategic breakthrough for new energy vehicles in the 21st century, with advantages such as high power performance, fast hydrogen refueling, and long driving range. Air compressors provide high-pressure air sources for fuel cell systems, and common types include centrifugal air compressors, screw air compressors, and scroll air compressors. Compared with screw and scroll air compressors, centrifugal air compressors have higher speeds and energy efficiency, and can provide higher pressure ratio air sources, thereby significantly improving the power density and overall performance of the stack.

[0003] The foil dynamic pressure gas thrust bearing is a type of dynamic pressure sliding bearing. It has the advantages of low friction loss, high speed, good high temperature stability, and no need for lubricating oil. It is very suitable for use in high-speed centrifugal air compressors. In related technologies, the typical structure of the foil dynamic pressure gas thrust bearing includes a bearing housing, a corrugated foil, and a top foil, which provide axial stiffness and damping for the rotor system.

[0004] Similar to the pads of the lubricating oil thrust bearing, the top foil of the foil dynamic pressure gas thrust bearing is generally designed in a fan shape to act as a pad. In order to ensure uniform force, the top foil is evenly distributed in the circumferential direction. The wave foil located on the lower side of the top foil has a corrugated structure, which plays an elastic support role and is the main source of stiffness and damping of the thrust bearing. One end of the wave foil and one end of the top foil are fixed to the bearing seat, and the other end of the wave foil and the other end of the top foil are free ends. There is a wedge-shaped convergence angle between the front end of the top foil and the bearing housing, and the rear end of the top foil is parallel to the bearing housing. When the rotor rotates at high speed, under the action of the above-mentioned wedge-shaped convergence angle, a dynamic pressure gas film is formed to support the rotor. Summary of the invention

[0005] The inventor has found through research that the key to the working of the foil dynamic pressure gas thrust bearing is to form a dynamic pressure gas film to support the rotor, but when this bearing is used in a hydrogen fuel cell vehicle, it will face the following technical problems: the vehicle needs to be started frequently, which means that the air compressor that provides the high-pressure gas source to the fuel cell system must also be started frequently with the vehicle, and the foil dynamic pressure gas thrust bearing, as a type of dynamic pressure bearing, has not yet formed an air film during the startup phase. In order to reduce bearing wear, the relevant technology increases the wedge convergence angle of the bearing to improve the dynamic pressure effect and quickly form an air film, but a wedge convergence angle that is too large will lead to a large air film pressure gradient and uneven air film pressure distribution, which is not conducive to bearing stability.

[0006] In view of this, the embodiments of the present disclosure provide a gas thrust bearing, a bearing assembly, a compressor, an air conditioner and an automobile, which can quickly form a stable dynamic pressure gas film.

[0007] In one aspect of the present disclosure, a bearing assembly is provided, comprising: a rotor having a rotating shaft and a thrust plate fixedly connected to or integrally formed with the rotating shaft; a bearing housing, sleeved on the rotating shaft and located on one side of the thrust plate along the axial direction of the rotor; and a plurality of foil groups, mounted on a side of the bearing housing adjacent to the thrust plate and arranged along the circumferential direction of the bearing housing, wherein at least one foil group of the plurality of foil groups comprises: a bump foil, located on a side of the bearing housing adjacent to the thrust plate, and one end of which is connected to the bearing housing; and a top foil, located on one side of the bump foil away from the bearing housing. side, and one end is connected to the bearing housing, wherein the top foil includes a first top foil segment and at least two second top foil segments, the first top foil segment is parallel to the surface of the thrust plate, and the at least two second top foil segments are inclined at an angle relative to the surface of the thrust plate; according to the rotation direction of the rotor when working, the first top foil segment is located downstream of the at least two second top foil segments, and the inclination angle of the second top foil segment located upstream of the at least two second top foil segments relative to the surface of the thrust plate is greater than the inclination angle of the second top foil segment located downstream of the at least two second top foil segments relative to the surface of the thrust plate.

[0008] In some embodiments, the first top foil segment and the at least two second top foil segments are connected sequentially along the circumference of the bearing housing.

[0009] In some embodiments, the top foil also includes: a third top foil segment, which is parallel to the surface of the thrust plate and has a greater distance from the surface of the thrust plate than the distance between the first top foil segment and the surface of the thrust plate, wherein, according to the rotation direction of the rotor during operation, the third top foil segment is located upstream of the at least two second top foil segments and is connected to the second top foil segment located upstream of the at least two second top foil segments.

[0010] In some embodiments, the inclination angles of the at least two second top foil segments relative to the surface of the thrust plate are both greater than 0° and less than 15°.

[0011] In some embodiments, a projected length of an upstream second foil segment among the at least two second foil segments on the surface of the thrust disk is smaller than a projected length of a downstream second foil segment among the at least two second foil segments on the surface of the thrust disk.

[0012] In some embodiments, each foil group in the plurality of foil groups has the same structure and size.

[0013] In some embodiments, the number of the plurality of foil groups is an even number greater than zero.

[0014] In some embodiments, an axial end surface of the bearing housing supporting the plurality of foil groups is parallel to a surface of the thrust plate.

[0015] In some embodiments, the bump foil includes a first bump foil segment located between the first top foil segment and the bearing housing, the first bump foil segment including a plurality of first corrugations and a plurality of second corrugations, the stiffness of the first corrugations being higher than the stiffness of the second corrugations.

[0016] In some embodiments, the height of the first corrugation is less than the height of the second corrugation.

[0017] In some embodiments, the span of the first corrugation is smaller than the span of the second corrugation.

[0018] In some embodiments, at least one of the first corrugations and at least one of the second corrugations are alternately arranged along an extension direction of the first top foil segment relative to the at least two second top foil segments.

[0019] In some embodiments, a first number of the first corrugations and a second number of the second corrugations are arranged alternately, and the first number is the same as the second number, or is smaller than the second number, or is larger than the second number.

[0020] In some embodiments, the wave foil also includes a second wave foil segment, which is located between the at least two second top foil segments and the bearing housing and connected to the first wave foil segment, and the second wave foil segment includes a plurality of third corrugations, and the heights of the plurality of third corrugations gradually increase along the rotation direction of the rotor during operation.

[0021] In one aspect of the present disclosure, a gas thrust bearing is provided, comprising: a bearing housing having an axial end face and an axially extending axial hole, wherein the axis of the axial hole is perpendicular to the axial end face of the bearing housing; and a plurality of foil groups, mounted on the axial end face of the bearing housing and arranged along the circumference of the bearing housing, wherein at least one foil group of the plurality of foil groups comprises: a bump foil, abutting against the axial end face of the bearing housing and having one end connected to the bearing housing; and a top foil, located on a side of the bump foil away from the bearing housing and having one end connected to the bearing housing, wherein the top foil The foil includes a first top foil segment and at least two second top foil segments, the first top foil segment is parallel to the axial end face of the bearing shell, and the at least two second top foil segments are inclined at an angle relative to the axial end face of the bearing shell; according to the rotation direction of the rotor relative to the bearing shell during operation, the first top foil segment is located downstream of the at least two second top foil segments, and the inclination angle of the second top foil segment located upstream of the at least two second top foil segments relative to the axial end face of the bearing shell is greater than the inclination angle of the second top foil segment located downstream of the at least two second top foil segments relative to the axial end face of the bearing shell.

[0022] In some embodiments, the inclination angles of the at least two second top foil segments relative to the axial end surface of the bearing housing are both greater than 0° and less than 15°.

[0023] In some embodiments, a projected length of a second top foil segment located upstream of the at least two second top foil segments on the axial end surface of the bearing housing is smaller than a projected length of a second top foil segment located downstream of the at least two second top foil segments on the axial end surface of the bearing housing.

[0024] In some embodiments, the bump foil includes a first bump foil segment located between the first top foil segment and the bearing housing, the first bump foil segment including a plurality of first corrugations and a plurality of second corrugations, the stiffness of the first corrugations being higher than the stiffness of the second corrugations.

[0025] In some embodiments, the height of the first corrugation is less than the height of the second corrugation.

[0026] In some embodiments, the span of the first corrugation is smaller than the span of the second corrugation.

[0027] In some embodiments, at least one of the first corrugations and at least one of the second corrugations are alternately arranged along an extension direction of the first top foil segment relative to the at least two second top foil segments.

[0028] In some embodiments, a first number of the first corrugations and a second number of the second corrugations are arranged alternately, and the first number is the same as the second number, or is smaller than the second number, or is larger than the second number.

[0029] In some embodiments, the wave foil also includes a second wave foil segment, which is located between the at least two second top foil segments and the bearing housing and connected to the first wave foil segment, and the second wave foil segment includes a plurality of third corrugations, and the heights of the plurality of third corrugations gradually increase along the rotation direction of the rotor during operation.

[0030] In one aspect of the present disclosure, a compressor is provided, comprising: the aforementioned bearing assembly, or the aforementioned gas thrust bearing.

[0031] In one aspect of the present disclosure, an air conditioner is provided, comprising: the aforementioned compressor, or the aforementioned bearing assembly, or the aforementioned gas thrust bearing.

[0032] In one aspect of the present disclosure, a vehicle is provided, comprising: the aforementioned compressor, or the aforementioned bearing assembly, or the aforementioned gas thrust bearing.

[0033] Therefore, according to the embodiment of the present disclosure, according to the rotation direction of the rotor during operation, at least two second top foil segments are provided upstream of the first top foil segment of the dynamic pressure bearing area in the top foil, so that the at least two second top foil segments are inclined at an angle (i.e., a wedge-shaped convergence angle) relative to the surface of the thrust plate, and the inclination angle of the second top foil segment located upstream relative to the surface of the thrust plate is greater than the inclination angle of the second top foil segment located downstream relative to the surface of the thrust plate, so that the dynamic pressure gas flows through the wedge-shaped gap with a wedge-shaped convergence angle from large to small and then enters the dynamic pressure bearing area. Since the wedge-shaped convergence angle corresponding to the second top foil segment located upstream is relatively large, a large-area sudden change wedge-shaped convergence area can be formed to improve the dynamic pressure effect of the bearing, so that the compressor can quickly form a dynamic pressure gas film during the startup process, reducing bearing wear. The wedge-shaped convergence angle corresponding to the second top foil segment located downstream is relatively small, and the area of ​​the formed wedge-shaped convergence area changes slightly, so that the pressure gradient mutation is relatively small, thereby reducing the gas film fluctuation, making the dynamic pressure gas film more stable, and thus reducing the rotor vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] 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.

[0035] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0036] Figure 1 is a schematic structural diagram of some embodiments of the bearing assembly according to the present disclosure;

[0037] Figure 2 is a schematic structural diagram of some embodiments of the bearing assembly according to the present disclosure from an axial perspective;

[0038] Figure 3 yes Figure 2 Schematic diagram of the AA section;

[0039] Figure 4 yes Figure 3 A magnified schematic diagram of the middle B area;

[0040] Figure 5 is a schematic diagram of the arrangement of the top foil in each foil group according to some embodiments of the bearing assembly of the present disclosure;

[0041] Figure 6 FIG. 4 is a schematic diagram of the arrangement of bump foils in each foil group in some embodiments of the bearing assembly according to the present disclosure.

[0042] 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

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] refer to Figure 1-Figure 6 In some embodiments, the bearing assembly includes: a rotor 10, a bearing housing 21 and a plurality of foil groups. The rotor 10 has a rotating shaft 12 and a thrust plate 11 fixedly connected to or integrally formed with the rotating shaft 12. The rotor 10 is configured to rotate around an axis 13. The bearing housing 21 is sleeved on the rotating shaft 12 and is located on one side of the thrust plate 11 along the axial direction of the rotor 10. The bearing housing 21 may be an annular thin plate-shaped part. A plurality of foil groups are mounted on the bearing housing 21 on one side adjacent to the thrust plate 11 and are arranged along the circumference of the bearing housing 21.

[0049] The overall shape of the foil group here can be a fan ring, so it can also be called a tile. The number of multiple foil groups can be an even number greater than 0, such as 4, 6, 8, etc., to improve the bearing capacity and stability of the bearing. Figure 5 and Figure 6 The bearing assembly may include 6 foil groups, and the 6 foil groups are evenly arranged along the circumferential direction on the surface of the bearing housing 21. In other embodiments, the number of the plurality of foil groups may also be an odd number.

[0050] In some embodiments, each foil group in the plurality of foil groups has the same structure and size, so that the dynamic pressure air film formed at each position of the bearing circumference is more uniform. In other embodiments, the foil groups in the plurality of foil groups may have different structures and sizes.

[0051] Among the multiple foil groups, at least one foil group includes a bump foil and a top foil. The bump foil is located on a side of the bearing housing 21 adjacent to the thrust plate 11, and one end is connected to the bearing housing 21. The top foil is located on a side of the bump foil away from the bearing housing 21, and one end is connected to the bearing housing 21.

[0052] refer to Figure 3 and Figure 4The top foil includes a first top foil segment 22 and at least two second top foil segments. The first top foil segment 22 is parallel to the surface of the thrust disk 11, and the at least two second top foil segments are inclined relative to the surface of the thrust disk 11. Figure 4 In the embodiment, at least two second top foil segments include second top foil segments 231 and 232, wherein in the rotation direction of the rotor 10 during operation, the second top foil segment 231 is located upstream, and the second top foil segment 232 is located downstream.

[0053] According to the rotation direction ω of the rotor 10 during operation, the first top foil segment 22 is located downstream of the at least two second top foil segments, and the second top foil segment located upstream of the at least two second top foil segments (e.g. Figure 4 The inclination angle θ1 of the second top foil segment 231 in the thrust plate 11 relative to the surface of the thrust plate 11 is greater than the second top foil segment (e.g. Figure 4 The second top foil segment 232 in the figure has an inclination angle θ2 relative to the surface of the thrust plate 11.

[0054] According to the principle of dynamic pressure effect, in order to form a dynamic pressure gas film, there is a wedge-shaped gap between the working surface of the top foil and the working surface of the thrust plate. The space between the two working surfaces is filled with a gas with a certain viscosity, such as air or gaseous refrigerant, and there is a relative sliding speed between the two working surfaces. The gas flows in from the larger cross-section of the wedge-shaped gap and flows out from the smaller cross-section.

[0055] In this embodiment, the first top foil segment 22 parallel to the surface of the thrust disc 11 forms a bearing area A1 with the thrust disc 11, and the bearing area A1 is the main bearing area of ​​the bearing. At least two second top foil segments are inclined at an angle (i.e., a wedge-shaped convergence angle) relative to the surface of the thrust disc 11. When the thrust disc 11 rotates at a high speed relative to the bearing housing 21 and the plurality of foil groups, the dynamic pressure gas with a certain viscosity is driven to flow through the wedge-shaped gap formed between the at least two second top foil segments and the thrust disc 11, and enter the bearing area A1. The high-pressure gas film formed in the bearing area A1 can support the thrust disc 11.

[0056] Since the wedge-shaped convergence angle (i.e., the inclination angle θ1) corresponding to the second top foil section located upstream is relatively large, a large-area sudden change wedge-shaped convergence area A2 can be formed to improve the dynamic pressure effect of the bearing, so that the compressor can quickly form a dynamic pressure air film during the startup process, reducing bearing wear. The wedge-shaped convergence angle (i.e., the inclination angle θ2) corresponding to the second top foil section located downstream is relatively small, and the area of ​​the formed wedge-shaped convergence area A3 changes slightly, so that the pressure gradient mutation is relatively small, avoiding the adverse effect of the pressure gradient mutation on the stability of the air film too quickly, thereby reducing the fluctuation of the air film, making the dynamic pressure air film more stable, and further reducing the vibration of the rotor. In this way, the requirements of bearing life and working stability of the frequently started automobile including the air compressor using this embodiment can be met to a greater extent.

[0057] refer to Figure 4 and Figure 5 In some embodiments, the top foil further includes a third top foil segment 24. The third top foil segment 24 is parallel to the surface of the thrust disk 11, and the distance between the third top foil segment 24 and the surface of the thrust disk 11 is greater than the distance between the first top foil segment 22 and the surface of the thrust disk 11. According to the rotation direction ω of the rotor 10 during operation, the third top foil segment 24 is located upstream of the at least two second top foil segments, and is located upstream of the second top foil segment (e.g. Figure 4 The second top foil segment 231) is connected.

[0058] The third top foil segment 24 can be overlapped on the corrugated foil and fixedly connected to the bearing housing 21 by welding or other fixing methods. The third top foil segment 24 forms an airflow inlet with the thrust plate 11. When the thrust plate 11 rotates at a high speed relative to the top foil, the airflow is driven to enter from the wider airflow inlet, and then enter the bearing area A1 through the wedge-shaped convergence areas A2 and A3.

[0059] The first top foil segment 22 and the at least two second top foil segments are sequentially connected along the circumference of the bearing housing 21. Figure 5 In the embodiment, the third top foil segment 24 is in the shape of a strip extending in the radial direction of the rotor 10, and the connection line between the first top foil segment 22 and the second top foil segment, the connection line between adjacent second top foil segments among the plurality of second top foil segments, and the connection line between the second top foil segment and the third top foil segment 24 are all parallel. The first top foil segment 22, the plurality of second top foil segments, and the third top foil segment together form a top foil in the shape of a fan ring.

[0060] The inclination angle of the second top foil segment relative to the surface of the thrust plate 11 can be determined comprehensively according to parameters such as bearing load, rotor speed, gas temperature, gas viscosity, etc. In some embodiments, the inclination angles of at least two second top foil segments relative to the surface of the thrust plate 11 are both greater than 0° and less than 15°.

[0061] The length of each second top foil segment can be designed so that the projection length L1 of the second top foil segment (e.g., the second top foil segment 231) located upstream among the at least two second top foil segments on the surface of the thrust plate 11 is smaller than the projection length L2 of the second top foil segment (e.g., the second top foil segment 232) located downstream among the at least two second top foil segments on the surface of the thrust plate 11. This helps the second top foil segment 231, which is shorter and has a larger wedge-shaped convergence angle, to quickly form a dynamic pressure air film during the compressor startup phase, thereby reducing bearing wear, and helps the second top foil segment 232, which is longer and has a smaller wedge-shaped convergence angle, to reduce pressure gradients and reduce air film fluctuations.

[0062] The inventor has found through research that the road conditions are complex when the car is driving, and it often accelerates and decelerates, so the air compressor needs to provide the fuel cell system with air sources of different pressures through variable speed. As the speed of the air compressor changes, the bearing stiffness required by the rotor system also changes, and generally increases with the increase of the speed. However, in the foil dynamic pressure gas thrust bearing, the bearing capacity of the single foil structure is determined after the bearing is assembled, and the adaptability of the formed air film strength is limited, and there is a problem that the bearing stiffness does not match the variable speed.

[0063] refer to Figure 4 and Figure 6 In some embodiments, the corrugated foil includes a first corrugated foil segment 25. The first corrugated foil segment 25 is located between the first top foil segment 22 and the bearing housing 21. The first corrugated foil segment 25 includes a plurality of first corrugations 251 and a plurality of second corrugations 252, and the stiffness of the first corrugations 251 is higher than the stiffness of the second corrugations 252. The second corrugations 252 with lower stiffness are used to meet the requirements for bearing stiffness at low speeds, and the first corrugations 251 with higher stiffness are used to meet the requirements for bearing stiffness at high speeds. By integrating the first corrugated foil segment with different stiffnesses to carry the dynamic pressure air film, the bearing capacity and bearing adaptability of the bearing can be effectively improved.

[0064] For the corrugated foil formed by the same material, the smaller the span and the smaller the corrugation height, the greater the stiffness. Conversely, the larger the span and the larger the corrugation height, the smaller the stiffness. Figure 4 In some embodiments, the height H1 of the first corrugation 251 is less than the height H2 of the second corrugation 252. When the rotor speed is low, the required bearing capacity is small. Since H2>H1, the second corrugation 252 with lower stiffness first contacts the top foil and provides stiffness support; as the speed gradually increases, the bearing capacity required by the rotor also increases, and the height H2 of the second corrugation 252 is compressed and reduced to provide greater bearing stiffness; when the speed increases to a certain extent, the height H2 of the second corrugation 252 is compressed to be equal to the height H1 of the first corrugation 251. At this time, the first corrugation 251 and the second corrugation 252 begin to jointly support the top foil and provide greater bearing stiffness.

[0065] In order to achieve a greater stiffness difference between different corrugations, refer to Figure 4 and Figure 6 In some embodiments, the span S1 of the first corrugation 251 can be smaller than the span S2 of the second corrugation 252, so as to further meet the bearing load requirements of the rotor with variable speed. In other embodiments, on the basis that the stiffness of the first corrugation 251 is higher than the stiffness of the second corrugation 252, the spans of the first corrugation 251 and the second corrugation 252 can also be equal.

[0066] In order to make the load distribution more uniform, Figure 4 and Figure 6 In the embodiment, at least one first corrugation 251 and at least one second corrugation 252 are alternately arranged along the extension direction of the first top foil segment 22 relative to the at least two second top foil segments 2, so that the formed high-pressure air film remains stable.

[0067] In order to further improve the load distribution uniformity of the bearing area A1 and keep the formed high-pressure air film stable, in some embodiments, a first number of the first corrugations and a second number of the second corrugations are arranged alternately, and the first number is the same as the second number. For example, one first corrugation and one second corrugation are arranged alternately, or two first corrugations and two second corrugations are arranged alternately, that is, arranged as two first corrugations, two second corrugations, two first corrugations, two second corrugations, etc.

[0068] In other embodiments, the numbers of the first corrugations and the second corrugations arranged alternately may be different. For example, the first number (e.g., 2 or 3) is greater than the second number (e.g., 1), which can improve the overall stiffness of the bearing and help the bearing adapt to the high speed of the rotor. For another example, the first number (e.g., 1) is less than the second number (e.g., 2 or 3), which can reduce the overall stiffness of the bearing and help the bearing adapt to the low speed of the rotor.

[0069] refer to Figure 4 and Figure 6 In some embodiments, the bump foil further comprises a second bump foil segment 26. The second bump foil segment 26 is located between the at least two second top foil segments and the bearing housing 21, and is connected to the first bump foil segment 25. That is, the second bump foil segment 26 corresponds to the wedge-shaped convergence area A2, and its shape also changes with the inclination angle of the second bump foil segment. Figure 4 In the embodiment, the second corrugated foil segment 26 includes a plurality of third corrugations, the heights of which gradually increase along the rotation direction ω of the rotor 10 during operation, so as to support the second corrugated foil segment which is arranged tilted.

[0070] refer to Figure 1-Figure 6The present disclosure also provides a gas thrust bearing, comprising: a bearing housing 21 and a plurality of foil groups. The gas thrust bearing can be manufactured and sold independently of the rotor 10. The bearing housing 21 has an axial end face and an axial hole extending therethrough in the axial direction, and the axis of the axial hole is perpendicular to the axial end face of the bearing housing 21. The axis of the axial hole coincides with the axis 13 of the rotating shaft of the rotor 10. A plurality of foil groups are mounted on the axial end face of the bearing housing 21 and are arranged along the circumference of the bearing housing 21.

[0071] At least one foil group among the plurality of foil groups includes a bump foil and a top foil. The bump foil abuts against the axial end surface of the bearing housing 21, and one end is connected to the bearing housing 21. The top foil is located on a side of the bump foil away from the bearing housing 21, and one end is connected to the bearing housing 21.

[0072] The top foil includes a first top foil segment 22 and at least two second top foil segments, the first top foil segment 22 is parallel to the axial end face of the bearing housing 21, and the at least two second top foil segments are inclined at an angle relative to the axial end face of the bearing housing 21; according to the rotation direction ω of the rotor 10 relative to the bearing housing 21 during operation, the first top foil segment 22 is located downstream of the at least two second top foil segments, and the inclination angle of the second top foil segment located upstream of the at least two second top foil segments relative to the axial end face of the bearing housing 21 is greater than the inclination angle of the second top foil segment located downstream of the at least two second top foil segments relative to the axial end face of the bearing housing 21.

[0073] When installing the gas thrust bearing, the axial end surface of the bearing housing 21 is parallel to the thrust disk of the rotor 10, and the rotating shaft 12 of the rotor 10 is inserted into the axial hole of the bearing housing 21. Accordingly, the inclination angle of at least two second top foil segments relative to the axial end surface of the bearing housing 21 is equal to the inclination angle of at least two second top foil segments relative to the surface of the thrust disk 11.

[0074] On this basis, the inclination angles of the at least two second top foil segments relative to the axial end surface of the bearing housing 21 may be greater than 0° and less than 15°. The projection length of the second top foil segment located upstream of the at least two second top foil segments on the axial end surface of the bearing housing 21 is less than the projection length of the second top foil segment located downstream of the at least two second top foil segments on the axial end surface of the bearing housing 21.

[0075] In some embodiments, the corrugated foil includes a first corrugated foil segment 25, the first corrugated foil segment 25 is located between the first top foil segment 22 and the bearing housing 21, the first corrugated foil segment 25 includes a plurality of first corrugations 251 and a plurality of second corrugations 252, and the stiffness of the first corrugations 251 is higher than the stiffness of the second corrugations 252. The second corrugations 252 with lower stiffness are used to meet the requirements for bearing stiffness at low speeds, and the first corrugations 251 with higher stiffness are used to meet the requirements for bearing stiffness at high speeds. By integrating the first corrugated foil segment with different stiffnesses to carry the dynamic pressure air film, the bearing capacity and bearing adaptability of the bearing can be effectively improved.

[0076] In some embodiments, the height of the first corrugation 251 is less than the height of the second corrugation 252. When the rotor speed is low, the required bearing capacity is small. Since H2>H1, the second corrugation 252 with lower stiffness first contacts the top foil and provides stiffness support; as the speed gradually increases, the bearing capacity required by the rotor also increases, and the height H2 of the second corrugation 252 is compressed and reduced to provide greater bearing stiffness; when the speed increases to a certain extent, the height H2 of the second corrugation 252 is compressed to be equal to the height H1 of the first corrugation 251. At this time, the first corrugation 251 and the second corrugation 252 begin to jointly support the top foil and provide greater bearing stiffness. Furthermore, the span of the first corrugation 251 can be smaller than the span of the second corrugation 252. This further adapts to the bearing load requirements of the rotor with variable speed.

[0077] In some embodiments, at least one first corrugation 251 and at least one second corrugation 252 are alternately arranged along the extension direction of the first top foil segment 22 relative to the at least two second top foil segments to make the load distribution of the bearing area A1 more uniform, thereby keeping the formed high-pressure air film stable.

[0078] In order to further improve the load distribution uniformity of the bearing area A1 and keep the formed high-pressure air film stable, in some embodiments, a first number of the first corrugations and a second number of the second corrugations are arranged alternately, and the first number is the same as the second number. For example, one first corrugation and one second corrugation are arranged alternately, or two first corrugations and two second corrugations are arranged alternately, that is, arranged as two first corrugations, two second corrugations, two first corrugations, two second corrugations, etc.

[0079] In other embodiments, the numbers of the first corrugations and the second corrugations arranged alternately may be different. For example, the first number (e.g., 2 or 3) is greater than the second number (e.g., 1), which can improve the overall stiffness of the bearing and help the bearing adapt to the high speed of the rotor. For another example, the first number (e.g., 1) is less than the second number (e.g., 2 or 3), which can reduce the overall stiffness of the bearing and help the bearing adapt to the low speed of the rotor.

[0080] In some embodiments, the wave foil further includes a second wave foil segment 26, the second wave foil segment 26 is located between the at least two second top foil segments and the bearing housing 21, and is connected to the first wave foil segment 25, the second wave foil segment 26 includes a plurality of third corrugations, the height of the plurality of third corrugations gradually increases along the rotation direction of the rotor 10 relative to the bearing housing 21 during operation. That is, the second wave foil segment 26 corresponds to the wedge-shaped convergence area A2, and its shape also changes with the inclination angle of the second wave foil segment. Figure 4 In the embodiment, the second corrugated foil segment 26 includes a plurality of third corrugations, the heights of which gradually increase along the rotation direction ω of the rotor 10 during operation, so as to support the second corrugated foil segment which is arranged tilted.

[0081] The various technical means involved in the various embodiments of the aforementioned bearing assembly can also be applied to the embodiments of the gas thrust bearing disclosed in the present invention. The relevant effects can be referred to the aforementioned description and will not be repeated here.

[0082] The present disclosure also provides a compressor, comprising the bearing assembly of any of the above embodiments or the gas thrust bearing of any of the above embodiments. The compressor can be a centrifugal air compressor, which can be applicable to hydrogen fuel cell vehicles, etc.

[0083] The present disclosure also provides an air conditioner, comprising: a compressor according to any of the aforementioned embodiments, or a bearing assembly according to any of the aforementioned embodiments, or a gas thrust bearing according to any of the aforementioned embodiments. The present disclosure also provides an air conditioner, comprising: a compressor according to any of the aforementioned embodiments, or a bearing assembly according to any of the aforementioned embodiments, or a gas thrust bearing according to any of the aforementioned embodiments.

[0084] 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.

[0085] 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 bearing assembly, characterized in that: include: A rotor (10) comprising a rotating shaft (12) and a thrust plate (11) fixedly connected to or integrally formed with the rotating shaft (12); a bearing housing (21), sleeved on the rotating shaft (12) and located on one side of the thrust plate (11) along the axial direction of the rotor (10); and A plurality of foil groups are mounted on a side of the bearing housing (21) adjacent to the thrust plate (11) and arranged along the circumference of the bearing housing (21). Wherein, at least one foil group among the plurality of foil groups comprises: A corrugated foil, located on a side of the bearing housing (21) adjacent to the thrust plate (11), and having one end connected to the bearing housing (21); and A top foil is located on a side of the bump foil away from the bearing housing (21), and one end of the top foil is connected to the bearing housing (21). The top foil comprises a first top foil segment (22) and at least two second top foil segments (231, 232); the first top foil segment (22) is parallel to the surface of the thrust plate (11); the at least two second top foil segments (231, 232) are inclined relative to the surface of the thrust plate (11); according to the rotation direction of the rotor (10) during operation, the first top foil segment (22) is located downstream of the at least two second top foil segments (231, 232); and the at least two second top foil segments (231, 232) are located downstream of the at least two second top foil segments (231, 232). The inclination angle of the second top foil segment (231, 232) located upstream relative to the surface of the thrust plate (11) is greater than the inclination angle of the second top foil segment (231, 232) located downstream among the at least two second top foil segments (231, 232) relative to the surface of the thrust plate (11), and the inclination angle of the second top foil segment (231, 232) located upstream among the at least two second top foil segments (231, 232) relative to the surface of the thrust plate (11) forms a wedge-shaped convergence area (A2) for improving the dynamic pressure effect of the bearing.

2. The bearing assembly according to claim 1, characterized in that: The first top foil segment (22) and the at least two second top foil segments (231, 232) are connected in sequence along the circumferential direction of the bearing housing (21).

3. The bearing assembly according to claim 1, characterized in that: The top foil also includes: The third top foil segment (24) is parallel to the surface of the thrust plate (11), and the distance between the third top foil segment (24) and the surface of the thrust plate (11) is greater than the distance between the first top foil segment (22) and the surface of the thrust plate (11). Wherein, according to the rotation direction of the rotor (10) during operation, the third top foil segment (24) is located upstream of the at least two second top foil segments (231, 232), and is connected to the second top foil segment (231, 232) located upstream of the at least two second top foil segments (231, 232).

4. The bearing assembly according to claim 1, characterized in that The inclination angles of the at least two second top foil segments (231, 232) relative to the surface of the thrust plate (11) are both greater than 0° and less than 15°.

5. The bearing assembly according to claim 1, characterized in that The projected length of the second top foil segment (231, 232) located upstream among the at least two second top foil segments (231, 232) on the surface of the thrust plate (11) is smaller than the projected length of the second top foil segment (231, 232) located downstream among the at least two second top foil segments (231, 232) on the surface of the thrust plate (11).

6. The bearing assembly according to claim 1, characterized in that Each foil group in the plurality of foil groups has the same structure and size.

7. The bearing assembly according to claim 1, characterized in that The number of the plurality of foil groups is an even number greater than zero.

8. The bearing assembly according to claim 1, characterized in that The axial end surface of the bearing housing (21) supporting the plurality of foil groups is parallel to the surface of the thrust plate (11).

9. The bearing assembly according to any one of claims 1 to 8, characterized in that: The corrugated foil comprises a first corrugated foil segment (25), wherein the first corrugated foil segment (25) is located between the first top foil segment (22) and the bearing housing (21), wherein the first corrugated foil segment (25) comprises a plurality of first corrugations (251) and a plurality of second corrugations (252), wherein the stiffness of the first corrugations (251) is higher than the stiffness of the second corrugations (252).

10. The bearing assembly according to claim 9, characterized in that The height of the first corrugation (251) is smaller than the height of the second corrugation (252).

11. The bearing assembly according to claim 10, characterized in that The span of the first corrugation (251) is smaller than the span of the second corrugation (252).

12. The bearing assembly according to claim 9, characterized in that At least one of the first corrugations (251) and at least one of the second corrugations (252) are alternately arranged along an extension direction of the first top foil segment (22) relative to the at least two second top foil segments (231, 232).

13. The bearing assembly according to claim 12, characterized in that A first number of the first corrugations (251) and a second number of the second corrugations (252) are arranged alternately, and the first number is the same as the second number, or is smaller than the second number, or is larger than the second number.

14. The bearing assembly according to claim 9, characterized in that The corrugated foil further comprises a second corrugated foil segment (26), the second corrugated foil segment (26) being located between the at least two second top foil segments (231, 232) and the bearing housing (21), and being connected to the first corrugated foil segment (25), the second corrugated foil segment (26) comprising a plurality of third corrugations, the heights of the plurality of third corrugations gradually increasing along the rotation direction of the rotor (10) during operation.

15. A gas thrust bearing, characterized in that: include: A bearing housing (21) having an axial end surface and an axial hole extending therethrough in the axial direction, wherein the axis of the axial hole is perpendicular to the axial end surface of the bearing housing (21); and A plurality of foil groups are mounted on the axial end surface of the bearing housing (21) and arranged along the circumference of the bearing housing (21). Wherein, at least one foil group among the plurality of foil groups comprises: A corrugated foil abutting against an axial end surface of the bearing housing (21) and having one end connected to the bearing housing (21); and A top foil is located on a side of the bump foil away from the bearing housing (21), and one end of the top foil is connected to the bearing housing (21). The top foil comprises a first top foil segment (22) and at least two second top foil segments (231, 232); the first top foil segment (22) is parallel to the axial end surface of the bearing housing (21); the at least two second top foil segments (231, 232) are inclined relative to the axial end surface of the bearing housing (21); according to the rotation direction of the rotor (10) relative to the bearing housing (21) during operation, the first top foil segment (22) is located downstream of the at least two second top foil segments (231, 232); and the at least two second top foil segments (231, 232) are located downstream of the at least two second top foil segments (231, 232). The inclination angle of the second top foil segment (231, 232) located upstream of the at least two second top foil segments (231, 232) relative to the axial end surface of the bearing housing (21) is greater than the inclination angle of the second top foil segment (231, 232) located downstream of the at least two second top foil segments (231, 232) relative to the axial end surface of the bearing housing (21), and the inclination angle of the second top foil segment (231, 232) located upstream of the at least two second top foil segments (231, 232) relative to the axial end surface of the bearing housing (21) forms a wedge-shaped convergence area (A2) for improving the dynamic pressure effect of the bearing.

16. The gas thrust bearing according to claim 15, characterized in that The inclination angles of the at least two second top foil segments (231, 232) relative to the axial end surface of the bearing housing (21) are both greater than 0° and less than 15°.

17. The gas thrust bearing according to claim 15, characterized in that The projected length of the second top foil segment (231, 232) located upstream among the at least two second top foil segments (231, 232) on the axial end surface of the bearing housing (21) is smaller than the projected length of the second top foil segment (231, 232) located downstream among the at least two second top foil segments (231, 232) on the axial end surface of the bearing housing (21).

18. The gas thrust bearing according to any one of claims 15 to 17, characterized in that: The corrugated foil comprises a first corrugated foil segment (25), wherein the first corrugated foil segment (25) is located between the first top foil segment (22) and the bearing housing (21), wherein the first corrugated foil segment (25) comprises a plurality of first corrugations (251) and a plurality of second corrugations (252), wherein the stiffness of the first corrugations (251) is higher than the stiffness of the second corrugations (252).

19. The gas thrust bearing according to claim 18, characterized in that The height of the first corrugation (251) is smaller than the height of the second corrugation (252).

20. The gas thrust bearing according to claim 19, characterized in that The span of the first corrugation (251) is smaller than the span of the second corrugation (252).

21. The gas thrust bearing according to claim 18, characterized in that At least one of the first corrugations (251) and at least one of the second corrugations (252) are alternately arranged along an extension direction of the first top foil segment (22) relative to the at least two second top foil segments (231, 232).

22. The gas thrust bearing according to claim 21, characterized in that A first number of the first corrugations (251) and a second number of the second corrugations (252) are arranged alternately, and the first number is the same as the second number, or is smaller than the second number, or is larger than the second number.

23. The gas thrust bearing according to claim 18, characterized in that The corrugated foil further comprises a second corrugated foil segment (26), the second corrugated foil segment (26) being located between the at least two second top foil segments (231, 232) and the bearing housing (21), and being connected to the first corrugated foil segment (25), the second corrugated foil segment (26) comprising a plurality of third corrugations, the heights of the plurality of third corrugations gradually increasing along the rotation direction of the rotor (10) relative to the bearing housing (21) when the rotor (10) is in operation.

24. A compressor, characterized in that: include: The bearing assembly according to any one of claims 1 to 14, or A gas thrust bearing as claimed in any one of claims 15 to 23.

25. An air conditioner, characterized in that: include: The compressor according to claim 24, or The bearing assembly according to any one of claims 1 to 14, or A gas thrust bearing as claimed in any one of claims 15 to 23.

26. A car, characterized in that: include: The compressor according to claim 24, or The bearing assembly according to any one of claims 1 to 14, or A gas thrust bearing as claimed in any one of claims 15 to 23.

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