Dynamic gas foil bearing and rotating machine

Abstract

The application discloses a dynamic pressure gas foil bearing and a rotating machine, wherein the dynamic pressure gas foil bearing comprises an elastic supporting foil which is an annular integrated structure; a top foil which is arranged on one side of the elastic supporting foil and is fixedly connected with the elastic supporting foil; and a supporting bottom plate, wherein the elastic supporting foil is arranged on one side of the supporting bottom plate, and the top foil is arranged on the side of the elastic supporting foil which is away from the supporting bottom plate; the top foil is mounted on the supporting bottom plate, and the top foil comprises a first end and a second end which are oppositely arranged along the circumference of the dynamic pressure gas foil bearing; and the first end and the second end of the top foil gradually approach the supporting bottom plate from the side of the circumferential middle part of the top foil to the side of the circumferential edge of the top foil, thereby forming a wedge-shaped structure. The application provides a dynamic pressure gas foil bearing and a rotating machine which have a reverse adaptation capability.

Description

Technical Field

[0001] This invention relates to the field of bearing technology, and more specifically, to a hydrodynamic gas foil bearing and rotating machinery. Background Technology

[0002] Hydrodynamic gas foil bearings utilize the wedge-shaped space formed between the rotor bearing disc and the bearing surface to create a wedge effect. As the rotor speed increases, due to the viscosity of the gas, surrounding gas is continuously drawn into the wedge-shaped space between the rotor and bearing. As the gas pressure within the wedge-shaped space increases, a hydrodynamic gas film forms when the bearing speed reaches a certain value, achieving a stable gas lubrication state. Under the hydrodynamic effect, the higher the speed, the higher the bearing's load-bearing capacity. Utilizing the gas film to bear the load significantly reduces friction. Compared to other types of bearings, gas bearings offer numerous advantages, including oil-free operation, no pollution, low operating resistance, simple structure, and low mechanical loss. Gas bearing technology overcomes many shortcomings of traditional liquid bearings, sliding bearings, and rolling bearings, and has been widely used in high-speed rotating machinery and precision machining machinery. It is particularly favored in applications such as food processing, brewing, and data centers. Under the requirements of energy conservation, emission reduction, and environmental protection, the application of hydrodynamic gas foil bearings has significant market potential and prospects.

[0003] While dynamic pressure gas foil bearings offer advantages during use, they also have drawbacks. Optimizing and improving their load-bearing capacity and mitigating the risk of burnout during reverse operation is crucial. For example, in the refrigeration centrifugal compressor and blower industries, during high-load operation, if an abnormal shutdown or a rapid load reduction is needed, the high-pressure side pressure cannot be quickly released. Without a power source, the compressor rotor may reverse under the influence of the high-pressure differential. In this situation, the bearing must have a certain anti-reverse rotation capability, but currently, dynamic pressure gas foil bearings do not possess this capability.

[0004] The hydrodynamic gas foil bearings of the relevant technology generally do not have anti-reverse rotation capability. When the rotor reverses, the hydrodynamic gas foil bearing may be damaged or even destroyed because it cannot form a hydrodynamic gas film. Summary of the Invention

[0005] This invention provides a dynamic pressure gas foil bearing and rotating machinery with reversible adaptability.

[0006] To achieve the above objectives, the present invention provides a hydrodynamic gas foil bearing, comprising: an elastic support foil, the elastic support foil being an integral annular structure; a top foil disposed on one side of the elastic support foil, the top foil being fixedly connected to the elastic support foil; a support base plate, the elastic support foil being disposed on one side of the support base plate, the top foil being disposed on the side of the elastic support foil away from the support base plate; the top foil is mounted on the support base plate, the top foil comprising a first end and a second end disposed opposite to each other along the circumference of the hydrodynamic gas foil bearing, the first end and the second end of the top foil respectively gradually approaching the support base plate from the side near the circumferential center of the top foil towards the circumferential edge of the top foil to form a wedge-shaped structure.

[0007] Furthermore, the elastic support foil includes a plurality of corrugated foil structures spaced apart, with a connection formed between two adjacent corrugated foil structures;

[0008] The elastic support foil is fixedly connected to the top layer foil through the connecting part.

[0009] Furthermore, the top foil includes multiple bearing plane areas, each of which corresponds one-to-one with the wave foil structure.

[0010] Furthermore, the top foil includes wedge-shaped regions, each corresponding to a connecting portion;

[0011] The bottom of the wedge-shaped region protrudes towards the elastic support foil, and the bottom of the wedge-shaped region is a welding plane, which is welded to the connecting part.

[0012] Furthermore, the elastic support foil is welded to the support base plate through the connecting part, the weld point between the connecting part and the support base plate is the first weld point, and the weld point between the bottom of the wedge-shaped region and the connecting part is the second weld point; the first weld point and the second weld point are distributed alternately.

[0013] Furthermore, the depth h1 of the wedge-shaped structure at the first end of the top foil is 0.05mm ≤ h1 ≤ 0.3mm;

[0014] The depth h2 of the wedge structure at the second end of the top foil is 0.05mm ≤ h2 ≤ 0.3mm.

[0015] Furthermore, the top foil includes wedge-shaped regions, each corresponding to a connecting portion;

[0016] Both the wedge-shaped region and the corresponding connecting part are provided with connecting ears, and the connecting ears are provided with positioning pins to fix the wedge-shaped region and the connecting part.

[0017] Furthermore, the top foil is an integrally formed structure, and the shape and structure of the elastic support foil match the shape of the top foil.

[0018] According to another aspect of the invention, a rotating machine is provided, comprising the aforementioned hydrodynamic gas foil bearing.

[0019] The hydrodynamic gas foil bearing of the present invention has a wedge-shaped structure formed at the first and second ends of the top layer foil, which gradually approaches the supporting base plate from the circumferential center of the top layer foil towards the circumferential edge of the top layer foil. Both ends of the top layer foil are wedge-shaped. When the rotor of the rotating machinery containing the hydrodynamic gas foil bearing rotates forward, a wedge-shaped space is formed between the wedge-shaped structure at one end of the top layer foil and the rotor, forming a hydrodynamic gas film to bear the rotor's force. When the rotation reverses, a wedge-shaped space is also formed between the wedge-shaped structure at the other end of the top layer foil and the rotor, again forming a hydrodynamic gas film to bear the rotor's force. This allows the hydrodynamic gas foil bearing to maintain its normal operating condition and avoids damage or even destruction due to the inability to form a hydrodynamic gas film, thus providing reverse rotation adaptability. The elastic support foil of the hydrodynamic gas foil bearing of the present invention is integrally stamped, forming a ring-shaped integrated structure. The ring-shaped, integrated elastic support foil has no free ends. Combined with the top foil and wedge-shaped structure, this ensures that the dynamic pressure gas foil bearing operates identically in both directions, giving it reverse rotation capability. The dynamic pressure gas foil bearing structure of this invention guarantees that the dynamic pressure gas thrust bearing operates identically in both forward and reverse rotations even in the event of an abnormal shutdown under extreme operating conditions. This ensures that even if reverse rotation occurs under extreme operating conditions, the thrust bearing can still maintain its normal operating state. This prevents damage or even destruction of the dynamic pressure gas foil bearing due to the inability to form a dynamic pressure gas film, thus providing reverse rotation adaptability. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the hydrodynamic gas foil bearing according to Embodiment 1 of the present invention;

[0021] Figure 2 This is a schematic diagram of the internal structure of the hydrodynamic gas foil bearing according to Embodiment 1 of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of the top foil of the hydrodynamic gas foil bearing according to Embodiment 1 of the present invention;

[0023] Figure 4 This is a front view schematic diagram of the hydrodynamic gas foil bearing according to Embodiment 1 of the present invention;

[0024] Figure 5 This is a schematic diagram of the elastic support foil of the hydrodynamic gas foil bearing according to Embodiment 1 of the present invention;

[0025] Figure 6 This is a schematic diagram of the structure of the hydrodynamic gas foil bearing according to Embodiment 2 of the present invention;

[0026] Figure 7 This is a schematic diagram of the elastic support foil of the dynamic pressure gas foil bearing according to Embodiment 2 of the present invention. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0028] Example 1

[0029] See Figures 1 to 5 As shown, according to Embodiment 1 of the present invention, a hydrodynamic gas foil bearing is provided. The hydrodynamic gas foil bearing includes an elastic support foil 10, a top foil 20, and a support base plate 30. The elastic support foil 10 is an integral annular structure. The top foil 20 is disposed on one side of the elastic support foil 10 and is fixedly connected to the elastic support foil 10. The elastic support foil 10 is disposed on one side of the support base plate 30, and the top foil 20 is disposed on the side of the elastic support foil 10 away from the support base plate 30. The top foil 20 is mounted on the support base plate 30. The top foil 20 includes a first end 20A and a second end 20B disposed opposite to each other along the circumference of the hydrodynamic gas foil bearing. The first end 20A and the second end 20B of the top foil 20 gradually approach the support base plate 30 from the side near the circumferential center of the top foil 20 towards the circumferential edge of the top foil 20 to form a wedge-shaped structure.

[0030] In the hydrodynamic gas foil bearing of the present invention, the first end 20A and the second end 20B of the top layer foil gradually approach the supporting base plate from the circumferential center of the top layer foil towards the circumferential edge of the top layer foil to form a wedge-shaped structure. Both circumferential ends of the top layer foil are set as wedge-shaped structures. When the rotor of the rotating machinery in which the hydrodynamic gas foil bearing is located rotates forward, a wedge-shaped space is formed between the wedge-shaped structure at one circumferential end of the top layer foil 20 and the rotor, which can form a hydrodynamic gas film to bear the force of the rotor. When the reverse rotation occurs, a wedge-shaped space can also be formed between the wedge-shaped structure at the other circumferential end of the top layer foil 20 and the rotor, which can also form a hydrodynamic gas film to bear the force of the rotor. This allows the hydrodynamic gas foil bearing to maintain its normal working state and avoid the problem of damage or even destruction of the hydrodynamic gas foil bearing due to the inability to form a hydrodynamic gas film, thus having the ability to adapt to reverse rotation. The elastic support foil of the hydrodynamic gas foil bearing of the present invention is integrally stamped to form a ring-shaped integrated structure. The ring-shaped, integrated elastic support foil has no free ends. Combined with the top foil and wedge-shaped structure, this ensures that the dynamic pressure gas foil bearing operates identically in both directions, giving it reverse rotation capability. The dynamic pressure gas foil bearing structure of this invention guarantees that the dynamic pressure gas thrust bearing operates identically in both forward and reverse rotations even in the event of an abnormal shutdown under extreme operating conditions. This ensures that even if reverse rotation occurs under extreme operating conditions, the thrust bearing can still maintain its normal operating state. This prevents damage or even destruction of the dynamic pressure gas foil bearing due to the inability to form a dynamic pressure gas film, thus providing reverse rotation adaptability.

[0031] Preferably, see Figure 4 and Figure 5 The elastic support foil 10 includes a plurality of corrugated foil structures 11 spaced apart, and a connecting portion 12 is formed between two adjacent corrugated foil structures 11;

[0032] The elastic support foil 10 is fixedly connected to the top layer foil 20 through the connecting part 12.

[0033] Multiple corrugated foil structures are spaced apart to fulfill the basic function of elastically supporting the foils, adapting to the support requirements of hydrodynamic gas foil bearings for rotors in rotating machinery. The connecting part is used to connect the top foil, without affecting the function of the corrugated foil structure, further adapting to the support requirements of hydrodynamic gas foil bearings for rotors in rotating machinery.

[0034] In this invention, the elastic support foil is integrally stamped and then laser-cut, with the specific structure as follows: Figure 5The elastic support foil 10 contains six evenly distributed groups of corrugated foil structures 11. Each group of corrugated foil structures consists of seven elastic support corrugated foils. The specific number may vary depending on the size and load-bearing characteristics. In most cases, the number of corrugated foil structures is preferably between 6 and 12. The number of elastic support corrugated foils in each group of corrugated foil structures is preferably between 6 and 15. The corrugated foil structures can be either variable height corrugated foil groups or equal height corrugated foil groups, depending on the size and load-bearing characteristics requirements.

[0035] Preferably, see Figure 3 The top foil 20 includes multiple bearing plane areas 21, and each bearing plane area 21 corresponds to one of the wave foil structures 11.

[0036] In this invention, the top foil is welded above the elastic support foil, and the bearing plane area is directly above the corrugated foil structure. This structure can ensure the functional stability of the corrugated foil structure.

[0037] In this embodiment, the top foil 20 includes a wedge-shaped region 22, which corresponds one-to-one with the connecting portion 12;

[0038] The bottom of the wedge-shaped region 22 protrudes towards the elastic support foil 10, and the bottom of the wedge-shaped region 22 is a welding plane. The bottom of the wedge-shaped region 22 is welded to the connecting part 12.

[0039] See Figure 1 and Figure 3 The wedge-shaped region 22 is a groove-shaped structure that protrudes towards the elastic support foil. As a key area for the formation of the gas film, the wedge-shaped region 22 is essential for the bearing to bear load. Furthermore, the bottom of the wedge-shaped region 22 is a welding plane used for welding with the elastic support foil. Structurally, this does not affect the corrugated foil structure, resulting in better welding and fixation, and thus stronger overall stability of the hydrodynamic gas foil bearing.

[0040] Combination Figure 1 and Figure 4 As shown, the elastic support foil 10 is welded to the support base plate 30 through the connecting part 12. The welding point between the connecting part 12 and the support base plate 30 is the first welding point C1, and the welding point between the bottom of the wedge-shaped region 22 and the connecting part 12 is the second welding point C2. The first welding point C1 and the second welding point C2 are distributed alternately.

[0041] The elastic support foil 10 can be fixed to the support base plate using a laser welding machine. The welding points are located on the connecting part 12, with 5-10 welding points per group. During the welding process, it should be ensured that the elastic support foil and the surface of the support base plate are in close contact. The first welding point C1 and the second welding point C2 are staggered, which effectively ensures the welding stability between the various components and improves the reliability of the bearing.

[0042] In this embodiment, the depth h1 of the wedge-shaped structure at the first end 20A of the top foil 20 is 0.05mm≤h1≤0.3mm;

[0043] The depth h2 of the wedge structure at the second end 20B of the top foil 20 is 0.05mm ≤ h2 ≤ 0.3mm.

[0044] In this invention, the inlet wedge height, specifically the depth of the wedge structure, is a crucial performance indicator. The inlet wedge height is controlled by adjusting the height of the corrugated foil structure. The wedge depth, h1 = h2, should ideally be controlled between 0.05-0.3 mm to balance various performance parameters and optimize bearing reliability and load-bearing capacity. A depth that is too small will increase bearing load to some extent, but this requires compromises in production efficiency and quality control costs. Conversely, an excessively large height difference will lead to a sharp decrease in bearing load, affecting bearing reliability.

[0045] Preferably, the top foil 20 is an integrally formed structure, and the shape and structure of the elastic support foil 10 match the shape of the top foil 20.

[0046] The top foil 20 also adopts an integrated structure. The integrally formed structure, combined with the elastic support foil, ensures that the working state of the hydrodynamic gas foil bearing is exactly the same when it rotates in both directions, and enables the hydrodynamic gas foil bearing to have the ability to rotate in reverse.

[0047] Example 2

[0048] See Figures 6 to 7As shown in Embodiment 2 of the present invention, a hydrodynamic gas foil bearing is provided. The hydrodynamic gas foil bearing includes an elastic support foil 10, a top foil 20, and a support base plate (not shown in the figure; the support base plate can be a structure formed on the surface of other components). The elastic support foil 10 is an integral annular structure. The top foil 20 is disposed on one side of the elastic support foil 10 and is fixedly connected to the elastic support foil 10. The elastic support foil 10 is disposed on one side of the support base plate, and the top foil 20 is disposed on the side of the elastic support foil 10 away from the support base plate. The top foil 20 is mounted on the support base plate. The top foil 20 includes a first end 20A and a second end 20B disposed opposite each other along the circumference of the hydrodynamic gas foil bearing. The first end 20A and the second end 20B of the top foil 20 gradually approach the support base plate from the side near the circumferential center of the top foil 20 towards the circumferential edge of the top foil 20 to form a wedge-shaped structure.

[0049] In the hydrodynamic gas foil bearing of the present invention, the first end 20A and the second end 20B of the top layer foil gradually approach the supporting base plate from the circumferential center of the top layer foil towards the circumferential edge of the top layer foil to form a wedge-shaped structure. Both circumferential ends of the top layer foil are set as wedge-shaped structures. When the rotor of the rotating machinery in which the hydrodynamic gas foil bearing is located rotates forward, a wedge-shaped space is formed between the wedge-shaped structure at one circumferential end of the top layer foil 20 and the rotor, which can form a hydrodynamic gas film to bear the force of the rotor. When the reverse rotation occurs, a wedge-shaped space can also be formed between the wedge-shaped structure at the other circumferential end of the top layer foil 20 and the rotor, which can also form a hydrodynamic gas film to bear the force of the rotor. This allows the hydrodynamic gas foil bearing to maintain its normal working state and avoid the problem of damage or even destruction of the hydrodynamic gas foil bearing due to the inability to form a hydrodynamic gas film, thus having the ability to adapt to reverse rotation. The elastic support foil of the hydrodynamic gas foil bearing of the present invention is integrally stamped to form a ring-shaped integrated structure. The ring-shaped, integrated elastic support foil has no free ends, ensuring that the dynamic pressure gas foil bearing operates identically in both directions, thus giving it reverse rotation capability. This structure guarantees that the dynamic pressure gas foil bearing operates identically in both forward and reverse directions even during abnormal compressor shutdowns under extreme conditions. It ensures that even if reverse rotation occurs under extreme operating conditions, the thrust bearing can maintain its normal operating state. This prevents damage or even destruction of the dynamic pressure gas foil bearing due to the inability to form a dynamic pressure gas film, thereby providing reverse rotation adaptability.

[0050] The elastic support foil 10 includes a plurality of corrugated foil structures 11 spaced apart, and a connecting portion 12 is formed between two adjacent corrugated foil structures 11.

[0051] The elastic support foil 10 is fixedly connected to the top layer foil 20 through the connecting part 12.

[0052] The top foil 20 includes a wedge-shaped region 22, which corresponds one-to-one with the connecting portion 12;

[0053] Both the wedge-shaped region 22 and the corresponding connecting part 12 are provided with connecting ears 40, and the connecting ears 40 are provided with positioning pins to fix the wedge-shaped region 22 and the connecting part 12.

[0054] In this embodiment, the hydrodynamic gas foil bearing needs to be mounted on other parts for installation and fixation. The hydrodynamic gas foil bearing is fixed to the surface of other parts, and the fixing surface not only serves a fixing function but also acts as a support base plate (i.e., the fixing surface of other parts forms a support base plate). During operation, the elastic support foil is directly pressed against the mounting component (other parts), and the elastic support foil and the top layer foil are connected by corresponding upper and lower connecting ears through positioning pins. This technical solution has higher adaptability and lower requirements for installation accuracy.

[0055] Example 3

[0056] According to a third embodiment of the present invention, a rotating machine is provided, which includes the above-described hydrodynamic gas foil bearing.

[0057] Rotating machinery includes, for example, centrifugal compressors and blowers. The hydrodynamic gas foil bearings included in rotating machinery can be, for example, hydrodynamic gas foil thrust bearings, hydrodynamic gas foil radial bearings, or hydrodynamic gas thrust-shear bearings. They can also simultaneously include hydrodynamic gas foil thrust bearings, hydrodynamic gas thrust-shear bearings, and hydrodynamic gas foil radial bearings.

[0058] The rotating machinery of this application embodiment has the advantages of the hydrodynamic gas foil bearing of this application embodiment.

[0059] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0060] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0061] Of course, the above are preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the basic principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A hydrodynamic gas foil bearing, characterized in that, include: The elastic support foil (10) is a ring-shaped integral structure, and the ring-shaped integral structure of the elastic support foil has no free ends; A top layer foil (20) is disposed on one side of the elastic support foil (10), and the top layer foil (20) is fixedly connected to the elastic support foil (10); A supporting base plate (30) is provided on one side of the supporting base plate (30), and a top layer foil (20) is provided on the side of the elastic supporting foil (10) away from the supporting base plate (30). The top layer foil (20) is installed on the supporting base plate (30). The top layer foil (20) includes a first end (20A) and a second end (20B) arranged opposite to each other along the circumference of the hydrodynamic gas foil bearing. The first end (20A) and the second end (20B) of the top layer foil (20) are respectively arranged along the circumference from the side near the circumferential middle of the top layer foil (20) to the side near the circumferential edge of the top layer foil (20) to gradually approach the supporting base plate (30) to form a wedge structure. Both ends of the top foil (20) are set as wedge-shaped structures. When the rotor of the rotating machinery where the dynamic pressure gas foil bearing is located rotates forward, the wedge-shaped structure at one end of the top foil (20) forms a wedge-shaped space with the rotor, which can form a dynamic pressure gas film to bear the force of the rotor. When the reverse rotation occurs, the wedge-shaped structure at the other end of the top foil (20) can also form a wedge-shaped space with the rotor, which can also form a dynamic pressure gas film to bear the force of the rotor. The elastic support foil (10) includes a plurality of corrugated foil structures (11) spaced apart, and a connecting part (12) is formed between two adjacent corrugated foil structures (11). The elastic support foil (10) is fixedly connected to the top foil (20) through the connecting part (12). The top foil (20) includes a plurality of bearing plane areas (21), and the bearing plane areas (21) correspond one-to-one with the corrugated foil structures (11).

2. The hydrodynamic gas foil bearing according to claim 1, characterized in that, The top foil (20) includes a wedge-shaped region (22), which corresponds one-to-one with the connecting part (12); The bottom of the wedge-shaped region (22) protrudes toward the elastic support foil (10), the bottom of the wedge-shaped region (22) is a welding plane, and the bottom of the wedge-shaped region (22) is welded to the connecting part (12).

3. The hydrodynamic gas foil bearing according to claim 2, characterized in that, The elastic support foil (10) is welded to the support base plate (30) through the connecting part (12). The welding point of the connecting part (12) and the support base plate (30) is the first welding point (C1), and the welding point of the bottom of the wedge region (22) and the connecting part (12) is the second welding point (C2). The first welding point (C1) and the second welding point (C2) are staggered.

4. The hydrodynamic gas foil bearing according to claim 1, characterized in that, The depth h1 of the wedge structure at the first end (20A) of the top foil (20) is 0.05mm ≤ h1 ≤ 0.3mm; The depth h2 of the wedge structure at the second end (20B) of the top foil (20) is 0.05mm ≤ h2 ≤ 0.3mm.

5. The hydrodynamic gas foil bearing according to claim 1, characterized in that, The top foil (20) includes a wedge-shaped region (22), which corresponds one-to-one with the connecting part (12); The wedge-shaped region (22) and the corresponding connecting part (12) are provided with connecting ears (40), and the connecting ears (40) are provided with positioning pins to fix the wedge-shaped region (22) and the connecting part (12).

6. The hydrodynamic gas foil bearing according to claim 1, characterized in that, The top foil (20) is an integrally formed structure, and the shape and structure of the elastic support foil (10) match the shape of the top foil (20).

7. A rotating machine, characterized in that, The hydrodynamic gas foil bearing includes any one of claims 1 to 6.

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