A thrust foil air bearing

Abstract

The present application relates to a thrust foil air bearing, which includes a top foil, a top support frame and a fixing assembly; the top support frame includes at least two support members arranged on the side of the top foil away from the thrust disk, and each support member is spaced apart so that a first clearance space is arranged between two adjacent support members; the top foil is provided with a dynamic pressure portion corresponding to each first clearance space one by one; the dynamic pressure portion can be deformed by force, so that the gap between it and the thrust disk can be quickly increased to allow gas to flow in, and the increase in the gap does not require the support member itself to be deformed, thereby allowing the dynamic pressure air film to be formed more quickly. The present application has the effect of reducing the takeoff speed of the top foil air bearing.

Description

Technical Field

[0001] The present application relates to the field of air bearings, and in particular to a thrust foil air bearing. Background Art

[0002] The thrust foil air bearing is a bearing that uses gas as a lubricating medium. Its principle is to use the dynamic pressure effect of gas to support the rotating body of the bearing through the gas, so that the rotating body and the inner ring of the bearing are suspended in the air, thereby reducing mechanical contact. The thrust foil air bearing has the characteristics of high temperature resistance, low friction, and less pollution. It is suitable for high-speed rotating bodies. It is currently used in high-speed centrifugal separators, gyro instruments, compressors for atomic reactor cooling, high-speed blowers and other fields.

[0003] In the related art, a Chinese invention application with application publication number CN107208694A discloses a thrust bearing, which is arranged opposite to a thrust collar arranged on a rotating shaft, and includes a top foil, a back foil and a substrate. The back foil is formed by a plurality of back foils arranged along the circumferential direction of the substrate, and the top foil is formed by a plurality of top foils respectively arranged on the back foil. An inner circumferential side recess is provided at a portion where the inner circumferential side end of the back foil is supported, and the top foil contacts the inner circumferential side recess.

[0004] The thrust collar is circumferentially fixed to the rotating shaft, and the thrust bearing is arranged on one side of the thrust collar. During operation, the rotating shaft drives the thrust collar to rotate at high speed. By utilizing the viscosity of the gas, the air between the thrust collar and the top foil gradually acquires kinetic energy and deforms the dynamic pressure gas film. The thrust collar breaks away from the contact state with the top foil and rotates in a non-contact manner. When the dynamic pressure gas film is formed from the beginning to the stability, the top foil gradually bends and deforms in the direction close to the back foil, increasing the distance between the top foil and the thrust collar so that the dynamic pressure gas film can be gradually and stably formed.

[0005] With respect to the above-mentioned related technologies, the inventors believe that when the top foil bends toward the direction approaching the back foil, the inner peripheral side concave portion on the back foil will gradually deform. However, since the inner peripheral side concave portion is arched as a whole and has great rigidity, it is difficult for the top foil to move away from the thrust collar in time, thereby increasing the difficulty of forming a dynamic pressure air film and improving the takeoff speed of the thrust foil air bearing. Summary of the invention

[0006] In order to reduce the take-off rotation speed, the present application provides a thrust foil air bearing.

[0007] The present application provides a thrust foil air bearing, which adopts the following technical solution:

[0008] A thrust foil air bearing, which can be rotatably connected to a rotating shaft and work in cooperation with a thrust disk, comprises a top foil which can be arranged on one side of the thrust disk, a top support frame for supporting the top foil, and a fixing assembly for fixing the top foil and the top support frame;

[0009] The top support frame comprises at least two support members arranged on the side of the top foil away from the thrust plate, and the support members are spaced apart so that a first clearance space is provided between two adjacent support members; the top foil is provided with a dynamic pressure portion corresponding to each of the first clearance spaces;

[0010] The top foil can abut against each support member in the working state, so that the dynamic pressure part is recessed toward the direction corresponding to the first clearance space, and a gap capable of accommodating the air film is formed between the dynamic pressure part and the thrust plate.

[0011] By adopting the above technical solution, the top support frame contacts the top foil through the support members arranged at intervals to prevent the top foil from moving axially along the rotating shaft as a whole, and the first clearance space between two adjacent support members forms a dynamic pressure part at the part of the top foil and the first clearance space. Since the dynamic pressure part is less supported by the support members, the dynamic pressure part can be depressed in the direction of entering the first clearance space when it is acted upon by the force of the dynamic pressure air film, so that the dynamic pressure part is slightly away from the thrust plate to increase the distance.

[0012] When the rotating shaft drives the thrust disk to start rotating, the air on the surface of the thrust disk gradually acquires kinetic energy to form a dynamic pressure air film. After the dynamic pressure air film is initially formed, it exerts a force on the top foil. The part of the top foil supported by the support will maintain a relatively stable state with the thrust disk, while the dynamic pressure part will gradually deform, thereby gradually increasing the gap between the top foil and the thrust disk for the dynamic pressure air film to melt and accommodate. The dynamic pressure part can deform by force, so that the gap between it and the thrust disk can be quickly increased to allow gas to flow in, and the increase in the gap does not require the support itself to deform, thereby allowing the dynamic pressure air film to form more quickly and reducing the takeoff speed of the top foil air bearing.

[0013] Optionally, the support member is provided with a support surface for contacting the top foil, and an area of ​​the support surface gradually increases in a direction away from a geometric center of the top support frame.

[0014] By adopting the above technical solution, the dynamic pressure air film exerts less force on the top foil at the smaller diameter. At this time, since the area of ​​the support surface is smaller at the small radius, the support degree of the support member to the top foil is also weaker, and the part of the dynamic pressure part close to the pilot air pit is prone to deformation, so that the dynamic pressure air film can be formed more quickly and stably. The dynamic pressure air film exerts greater force on the top foil at the larger diameter. Since the support degree of the support member to the top foil is stronger at the larger diameter, the risk of excessive deformation of the top foil can be reduced and the dynamic pressure air film can be locked, slowing down the leakage rate of gas and ensuring the working stability of the dynamic pressure air film.

[0015] Optionally, the top foil is provided with a connecting hole for the rotating shaft to pass through, the top foil is attached to the thrust plate, and a pilot air pit for accommodating gas is provided on a side of the top foil away from the thrust plate, and the pilot air pit is connected to the connecting hole.

[0016] By adopting the above technical solution, a slight drop can be formed between the pit mouth and the pit bottom of the pilot air pit; this drop allows a slight gap to be left between the pilot air pit and the thrust plate even when the top foil is in contact with the thrust plate, through which gas can enter between the top foil and the thrust plate, and the gas can be used to gradually deform the variable pressure air film.

[0017] Optionally, the top support frame further comprises a fixing ring connected to the fixing assembly, the fixing ring is coaxial with the top foil, and each of the supporting members is circumferentially distributed on an inner circle of the fixing ring.

[0018] By adopting the above technical solution, the support members are fixed by the fixing ring, and the support members are distributed in a circular pattern, so that the support members can support the top foil more evenly.

[0019] Optionally, the pilot air pits are arranged on a side of the dynamic pressure portion close to the connecting hole, so that the pilot air pits are distributed in a circle around the connecting hole.

[0020] By adopting the above technical solution, the pilot air pit is equivalent to the initial generation point of the dynamic pressure air film, and each pilot air pit is distributed in a circle around the connecting hole, so that the dynamic pressure air film can be generated from multiple positions simultaneously.

[0021] Optionally, it also includes at least one group of reinforcement components arranged on the side of the top support frame away from the top foil, the reinforcement component includes a load adjustment plate and a load frame for supporting the load adjustment plate, the load frame is arranged on the side of the load adjustment plate away from the top support frame, and the load adjustment plate can interfere with the adjacent top support frame and / or the load frames adjacent to other reinforcement components.

[0022] By adopting the above technical solution, the load adjustment plate can support the adjacent top support frame and / or other adjacent load frames, so that the top support frame and the top foil can be fixed in the fixing assembly.

[0023] Optionally, the load frame includes at least two load members arranged on a side of the top support frame away from the top foil; the load members are spaced apart so that a second clearance space is provided between two adjacent load members;

[0024] Each second clearance space on any of the load racks has an overlapping portion with the support member on the adjacent top support rack and / or the load member on the adjacent load rack.

[0025] By adopting the above technical solution, both sides of the load adjustment plate can be subjected to force, including the situation that the support member and the load member respectively contact the two sides of the same load adjustment plate, and the situation that the load members on the two load frames respectively contact the two sides of the same load adjustment plate. In the above two situations, both sides of the load adjustment plate can undergo slight deformation, so that the load adjustment plate forms a depression in the direction of entering the first clearance space or the second clearance space, thereby reducing the minimum distance between the two sides of the load adjustment plate in the axial direction of the bearing, so that the top foil and the top support frame can undergo slight displacement in the direction away from the thrust disk, so that the dynamic pressure air film acts completely on the top foil, so that the thrust foil air bearing can work more stably.

[0026] Optionally, the number of the load members corresponds to the number of the support members; the load members on any one of the load racks are staggered with the support members on the top support rack and / or the load members on other adjacent load racks.

[0027] By adopting the above technical solution, when the support members and the load members respectively contact the two sides of the same load adjustment plate, the support members and the load members are staggered; when the load members on the two load racks respectively contact the two sides of the same load adjustment plate, the load members on the two load racks are staggered.

[0028] Optionally, the area of ​​a side of the load-bearing member close to the top support frame gradually increases in a direction away from the geometric center of the load frame.

[0029] By adopting the above technical solution, as the radius increases, the force of the dynamic pressure air film on the top support frame also increases. Since the area of ​​the side of the load member close to the top support frame gradually increases in the direction away from the geometric center of the load frame, the supporting force of the load member on the top support frame also increases with the radius, matching the pressure distribution of the dynamic pressure air film, thereby achieving better stability.

[0030] Optionally, the angle formed between the two sides of the first clearance space and / or the two sides of the second clearance space is -0.1° to 0.1°; preferably, the maximum arc length of the first clearance space (43) is 1.5 to 2.5 times the maximum width of the support member (42); and the maximum arc length of the second clearance space (73) is 1.5 to 2.5 times the maximum width of the load member (72).

[0031] By adopting the above technical solution, the two sides of the first give way space are almost parallel to each other, the two sides of the second give way space are also almost parallel to each other, and the width of the first give way space is adapted to the width of the second give way space, so that the gap formed by the staggered distribution between the first give way space and the second give way space is more uniform.

[0032] Optionally, the fixing assembly includes a bearing seat and a retaining frame detachably connected to the bearing seat, and the top support frame and the top foil are both arranged in the retaining frame; the inner ring of the retaining frame has at least two limiting grooves for positioning the top foil and / or the top support frame, the top foil is provided with a first positioning piece for plugging into the limiting groove, and the top support frame is provided with a second positioning piece for plugging into the limiting groove.

[0033] By adopting the above technical solution, the retaining frame limits the first positioning member and the second positioning member respectively through the limiting grooves to prevent the top support frame or the top foil from being displaced in the circumferential direction.

[0034] Optionally, the limiting groove is connected to one side of the retaining frame to form a notch portion, and the retaining frame is detachably connected to a retaining ring for covering the notch portion to prevent the first positioning member and / or the second positioning member from escaping from the limiting groove.

[0035] By adopting the above technical solution, the retaining ring can prevent the first positioning member and the second positioning member from being separated from the limiting groove, so that the top foil and the top support frame are fixed in the retaining frame. After the user removes the retaining ring, the user can remove the first positioning member or the second positioning member from the notch portion, thereby removing the top foil and the top support frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the thrust foil air bearing of an embodiment of the present application in a working state.

[0037] Figure 2 Schematic diagram of the structure of the thrust foil air bearing according to an embodiment of the present application.

[0038] Figure 3 yes Figure 1 Exploded view of the fixing components, top foil, top support frame and reinforcement components.

[0039] Figure 4 It is a schematic diagram of the state changes before the formation of the dynamic pressure air film, during the formation of the dynamic pressure air film and after the dynamic pressure air film is stabilized, wherein the hollow dashed arrow refers to the pressure exerted by the dynamic pressure air film on the top foil.

[0040] Figure 5 It is a schematic diagram of the distribution of supports.

[0041] Figure 6 yes Figure 2 Schematic diagram of the explosion between the top foil, top support frame, load adjustment plate and load frame.

[0042] Figure 7 It is a schematic diagram of the state of the top foil, the top support frame, the load adjustment plate and the load frame after the dynamic pressure air film is stabilized.

[0043] Description of reference numerals:

[0044] 1. Rotating shaft; 2. Thrust plate; 3. Top foil; 31. Connecting hole; 32. Lubricating coating; 33. Dynamic pressure part; 34. Interference part; 35. Pilot air pit; 36. First positioning member; 4. Top support frame; 41. Fixing ring; 411. Second positioning member; 42. Support member; 421. Support surface; 43. First clearance space; 5. Reinforcement assembly; 51. Load adjustment plate; 511. Third positioning member; 6. Fixing assembly; 61. Bearing seat; 611. Accommodating space; 62. Retaining frame; 621. Limiting groove; 622. Notch; 63. Retaining ring; 64. Locking screw; 7. Load frame; 71. Connecting ring; 72. Load member; 721. Force surface; 73. Second clearance space; 74. Fourth positioning member. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In addition, the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article, unless otherwise specified, generally means that the associated objects before and after are in an "or" relationship.

[0047] The following is attached to the instruction manual Figures 1 to 7 The embodiments of the present invention are described in further detail.

[0048] The present application embodiment discloses a thrust foil air bearing. Figure 1 , the thrust foil air bearing needs to cooperate with the rotating shaft 1 and the thrust disk 2 respectively when working, wherein the rotating shaft 1 is inserted into the thrust foil air bearing, and the rotating shaft 1 is rotatably connected with the thrust foil air bearing; the thrust disk 2 is circumferentially fixed with the rotating shaft 1, and the thrust foil air bearing is arranged on one side of the thrust disk 2; the rotating shaft 1, the thrust foil air bearing and the thrust disk 2 are coaxial, and the thrust foil air bearing and the thrust disk 2 are relatively fixed in the axial direction. It can be understood that when the number of thrust foil air bearings is 1, the thrust foil air bearing is only arranged on one side of the thrust disk 2; when the number of thrust foil air bearings is 2, the two thrust foil air bearings can be respectively arranged on the two sides of the thrust disk 2. In this embodiment, the number of thrust foil air bearings is 1 as an example.

[0049] Reference Figure 1 When in working state, the rotating shaft 1 drives the thrust plate 2 to rotate at high speed, so that the gas between the thrust plate 2 and the thrust foil air bearing gradually has kinetic energy to form a dynamic pressure air film. When the dynamic pressure air film is stable, the dynamic pressure air film can support the rotating shaft 1, so that the rotating shaft 1 is gradually suspended in the thrust foil air bearing, reducing the mechanical contact between the rotating shaft 1 and the thrust foil air bearing.

[0050] For the convenience of description, the "thrust foil air bearing" will be referred to as the "bearing body" below, and the "axial direction of the thrust foil air bearing" will be referred to as the "bearing axial direction", the "circumferential direction of the thrust foil air bearing" will be referred to as the "bearing circumferential direction", and the "radial direction of the thrust foil air bearing" will be referred to as the "bearing radial direction".

[0051] Reference Figure 1 and Figure 2 The bearing body includes a top foil 3, a top support frame 4, a reinforcement component 5 and a fixing component 6, wherein the top foil 3, the top support frame 4 and the reinforcement component 5 are all installed in the fixing component 6 as internal components of the bearing, and the fixing component 6 and the thrust plate 2 are relatively fixed in the axial direction of the bearing, and the fixing component 6 has the functions of fixing and protecting the internal components of the bearing; the top foil 3 is attached to the thrust plate 2; the top support frame 4 is arranged on the side of the top foil 3 away from the thrust plate 2, and the top support frame 4 limits the maximum width of the gap between the top foil 3 and the thrust plate 2 by preventing the top foil 3 from moving as a whole in the direction away from the thrust plate 2; the reinforcement component 5 is arranged on the side of the top support frame 4 away from the top foil 3, and the reinforcement component 5 can provide support force for the top support frame 4 on the one hand, and on the other hand, the reinforcement component 5 can produce a slight displacement in the axial direction of the bearing by slight deformation itself, thereby adjusting the maximum width of the gap between the top foil 3 and the thrust plate 2.

[0052] Reference Figure 1 and Figure 2 Specifically, the fixing assembly 6 includes a bearing seat 61 as a basic structure, a retaining frame 62 for forming an accommodating space with the bearing seat 61, and a retaining ring 63 installed on the retaining frame 62. The bearing seat 61 is annular in shape as a whole, and the inner diameter of the bearing seat 61 is slightly larger than the diameter of the rotating shaft 1, so that the rotating shaft 1 can pass through the bearing seat 61 and reduce the friction between the rotating shaft 1 and the bearing seat 61 when rotating.

[0053] Reference Figure 3 The retainer 62 is generally annular and is arranged along the periphery of the bearing seat 61. The outer diameter of the retainer 62 is consistent with the outer diameter of the bearing seat 61, and the inner diameter of the retainer 62 is larger than the inner diameter of the bearing seat 61, so that an accommodating space 611 for installing the internal components of the bearing is formed between the inner side of the retainer 62 and the surface of the bearing seat 61, and the retainer 62 itself has a limiting effect on the internal components of the bearing, which can limit the displacement of the internal components of the bearing in the circumferential direction of the bearing.

[0054] Reference Figure 3 Furthermore, the inner ring of the retainer 62 is provided with a plurality of spaced limiting grooves 621, which are used to limit the top foil 3, the top support frame 4, and the reinforcement assembly 5 in the circumferential direction of the bearing. The notch of the limiting groove 621 points to the axis of the retainer 62 along the radial direction of the bearing; preferably, the number of the limiting grooves 621 is 4, and each limiting groove 621 is distributed circumferentially along the inner ring of the retainer 62. The limiting groove 621 penetrates the retainer 62 along the axial direction of the bearing, and forms a notch 622 on the side of the retainer 62 away from the bearing seat 61. The notch 622 can allow the top foil 3, the top support frame 4 or the reinforcement assembly 5 to be inserted into the limiting groove 621, which is equivalent to the passage opening for the top foil 3, the top support frame 4 and the reinforcement assembly 5 to enter and exit each limiting groove 621.

[0055] Reference Figure 3 It can be understood that the thickness of the retaining frame 62 affects the size of the accommodating space 611. As the thickness of the retaining frame 62 increases, the volume of the accommodating space 611 also increases. However, the processing difficulty and processing cost of the retaining frame 62 will also increase. In order to reduce the overall processing cost of the retaining frame 62, in this embodiment, the retaining frame 62 is composed of a plurality of steel rings stacked along the axial direction of the bearing, and the steel rings all use the same processing parameters; preferably, the various steel rings that constitute the same retaining frame 62 are all processed in the same batch.

[0056] Reference Figure 3The retaining ring 63 is in the shape of a circular ring as a whole. The retaining ring 63 is arranged on the side of the retaining frame 62 away from the bearing seat 61. The retaining ring 63 prevents the top foil 3, the top support frame 4 or the reinforcing component 5 from axially disengaging from the limiting groove 621 along the bearing by blocking the notch 622, thereby making the top foil 3, the top support frame 4, the reinforcing component 5 relatively fixed to the retaining frame 62. Preferably, the inner diameter and outer diameter of the retaining ring 63 are consistent with the inner diameter and outer diameter of the retaining frame 62. Preferably, the bearing seat 61, the retaining frame 62 and the retaining ring 63 are all made of SS304 steel; in other embodiments, the user can also change the material of the bearing seat 61, the retaining frame 62 or the retaining ring 63 according to the actual scene.

[0057] Reference Figure 3 Furthermore, the fixing part assembly also includes a plurality of locking screws 64, each of which is distributed in a circle around the retaining ring 63. The locking screws 64 are sequentially inserted through the retaining ring 63, the retaining frame 62 and the bearing seat 61 along the axial direction of the bearing and connected to the nut, so that the retaining ring 63, the retaining frame 62 and the bearing seat 61 are relatively fixed; the user can disassemble the bearing body by screwing out the locking screws 64, which is convenient for the user to repair the bearing body and also convenient for the user to assemble the bearing body. Preferably, the number of the locking screws 64 is 4; each locking screw 64 is staggered with each limiting groove 621 to reduce the possible position interference between the locking screws 64 and the limiting groove 621.

[0058] Reference Figure 1 and Figure 3 The top foil 3 is located at one end of the accommodation space 611 away from the bearing base. The top foil 3 is annular as a whole. The outer diameter of the top foil 3 is smaller than the inner diameter of the retainer 62, and the inner diameter of the top foil 3 is slightly larger than the diameter of the rotating shaft 1. The inner ring of the top foil 3 forms a connecting hole 31 for the rotating shaft 1 to penetrate. Preferably, a gap of 2 mm is left between the inner ring of the top foil 3 and the outer peripheral wall of the rotating shaft 1. The outer diameter of the top foil 3 is 1.5 to 2.5 times the inner diameter of the top foil 3; in this embodiment, the outer diameter of the top foil 3 is twice the inner diameter of the top foil 3. The top foil 3 is sprayed with a lubricating coating 32 on the side away from the accommodation space 611. The composition of the lubricating coating 32 includes but is not limited to high temperature resistant coating and wear resistant coating. When the dynamic pressure air film is not fully formed, the top foil 3 is attached to the thrust plate 2 through the lubricating coating 32. The lubricating coating 32 can reduce the wear and heat between the top foil 3 and the thrust plate 2.

[0059] Reference Figure 1 and Figure 3The top foil 3 is provided with a plurality of dynamic pressure parts 33 and a plurality of abutment parts 34, which are staggered so that each dynamic pressure part 33 is circumferentially spaced around the top foil 3. The abutment parts 34 are used to connect with the top support frame 4 so that the top foil 3 is relatively fixed to the top support frame 4 as a whole; the dynamic pressure part 33 can be gradually recessed in the direction of entering the top support frame 4, so that a gradually increasing gap can be formed between the top foil 3 and the thrust plate 2.

[0060] Reference Figure 1 and Figure 3 , a plurality of pilot air pits 35 are also provided on the side of the dynamic pressure portion 33 away from the accommodation space 611, and each pilot air pit 35 is connected to the connecting hole 31, and a slight drop can be formed between the pit mouth and the pit bottom of the pilot air pit 35; the drop allows the top foil 3 to leave a slight gap between the top foil 3 and the thrust disk 2 through the pilot air pit 35 even when it is attached to the thrust disk 2, and the gap allows gas (such as air) to enter between the top foil 3 and the thrust disk 2, so the pilot air pit 35 is equivalent to the initial generation point of the dynamic pressure air film. In the embodiment of this city, each pilot air pit 35 is distributed in a circle around the connecting hole 31, which can make the gas distribution between the top foil 3 and the thrust disk 2 more uniform along the circumference of the bearing.

[0061] Reference Figure 1 and Figure 3 In the present embodiment, the pilot air pit 35 is not formed by providing a groove on the top foil 3, but is formed by leaving the lubricating coating 32 hollow, that is, when processing the lubricating coating 32, the portion of the top foil 3 where the pilot air pit 35 is provided is not sprayed with paint, so that the pilot air pit 35 is formed, thereby reducing the processing steps and processing costs. On the other hand, since the pilot air pit 35 itself does not produce mechanical contact with the thrust plate 2, there is no need to reduce mechanical friction through the lubricating coating 32.

[0062] Reference Figure 1 and Figure 3 When the dynamic pressure air film is not fully formed, the top foil 3 is attached to the thrust plate 2 through the lubricating coating 32, and the inner ring of the top foil 3 is attached to the outer peripheral wall of the rotating shaft 1; when the rotating shaft 1 starts to rotate, the kinetic energy of the gas in the pilot air pit 35 begins to increase, and a dynamic pressure air film is gradually formed; in the process of the dynamic pressure air film gradually and stably forming, the dynamic pressure part 33 gradually deforms to increase the gap between the top foil 3 and the thrust plate 2, and a small gap will gradually be generated between the inner ring of the top foil 3 and the outer peripheral wall of the rotating shaft 1; when the dynamic pressure air film is stably formed, the dynamic pressure air film, on the one hand, makes the rotating shaft 1 suspended in the inner ring of the top foil 3, and on the other hand, maintains the gap between the top foil 3 and the thrust plate 2, thereby completely reducing the mechanical contact between the rotating shaft 1 and the bearing body.

[0063] Reference Figure 3Furthermore, the top foil 3 is integrally formed with a plurality of first positioning members 36 corresponding to the respective limiting grooves 621, and each first positioning member 36 is arranged along the radial direction of the bearing, and each first positioning member 36 is inserted into the corresponding limiting groove 621, so that the top foil 3 is fixed in the retaining frame 62. It is understandable that after the retaining ring 63 is disassembled, the user can remove the first positioning member 36 from the limiting groove 621, or reinstall the first positioning member 36 in the limiting groove 621.

[0064] Reference Figure 3 The top support frame 4 includes a fixing ring 41 installed in the retaining frame 62, and a supporting member 42 installed in the fixing ring 41. The outer diameter of the fixing ring 41 is consistent with the inner diameter of the retaining frame 62. The outer peripheral wall of the fixing ring 41 is provided with a plurality of second positioning members 411 corresponding to each limiting groove 621. Each second positioning member 411 is arranged along the radial direction of the bearing. Each second positioning member 411 is inserted into the corresponding limiting groove 621 and contacts the first positioning member 36 located in the same limiting groove 621.

[0065] Reference Figure 1 and Figure 3 In this embodiment, the number of the support members 42 is 12. In other embodiments, the designer sets the number of the support members 42 according to actual needs, such as 4, 6, 8, etc. Each support member 42 is distributed along the inner ring of the fixed ring 41 at intervals in a circle. Each support member 42 points to the axis of the fixed ring 41. A first clearance space 43 is formed between two adjacent support members 42. The support member 42 can support the top foil 3 by contacting the top foil 3. The side of the support member 42 close to the top foil 3 forms a support surface 421. In this embodiment, the maximum length of the support member 42 in the radial direction of the bearing is slightly smaller than the inner diameter difference between the fixed ring 41 and the top foil 3, so that the support member 42 can maintain sufficient support for the top foil 3 while reducing the mechanical friction between the end of the support member 42 and the rotating shaft 1. Preferably, each second positioning member 411 and each support member 42 are integrally formed with the fixed ring 41 to reduce the processing steps and production cost of the top support frame 4.

[0066] Reference Figure 3 It can be understood that the top support frame 4 is coaxially arranged with the top foil 3, and under the limiting effect of the limiting groove 621, the top support frame 4 and the top foil 3 can be relatively stable in the circumferential direction of the bearing even under the effect of the force of the dynamic pressure gas film. When the top foil 3 is pushed by the dynamic pressure gas film, the top foil 3 as a whole abuts against the top support frame 4, so that the supporting surfaces 421 of each support member 42 abut against the top foil 3. In this embodiment, the portions on the top foil 3 corresponding to each supporting surface 421 form each abutting portion 34, and the portions corresponding to each first clearance space 43 form each dynamic pressure portion 33.

[0067] Reference Figure 3 and Figure 4 When the top foil 3 is pushed by the dynamic pressure gas film to contact the top support frame 4, each support member 42, as a supporting structure, contacts each contact portion 34, so that the top foil 3 and the top support frame 4 are relatively fixed in the axial direction of the bearing, and the contact portion 34 is prevented from being recessed in the direction away from the thrust plate 2; and since there is no supporting structure inside the first clearance space 43, each dynamic pressure portion 33 will be recessed in the direction of entering each first clearance space 43, gradually increasing the gap between the dynamic pressure portion 33 and the thrust plate 2, so as to allow the gas in the pilot air pit 35 to enter, thereby gradually expanding the scope of action of the dynamic pressure gas film and stabilizing it. At the same time, the dynamic pressure portion 33 approaches the rotating shaft 1 (refer to Figure 1 ) will also become concave so that the gap between the inner ring of the top foil 3 and the outer peripheral wall of the rotating shaft 1 will be slightly increased.

[0068] Reference Figure 4 The principle of the dynamic pressure part 33 being sunken is that the abutment parts 34 on both sides of the dynamic pressure part 33 can be supported by the support surface 421, but there is no structure supporting the dynamic pressure part 33 inside the first clearance space 43, and the unbalanced force between the dynamic pressure part 33 and the abutment part 34 causes the dynamic pressure part 33 to deform, and the deformation degree of the parts on both sides of the dynamic pressure part 33 close to the abutment part 34 is small, while the deformation degree of the middle part of the dynamic pressure part 33 is large. Since the top foil 3 is integrally formed, there is no very obvious boundary between the dynamic pressure part 33 and the abutment part 34. When the dynamic pressure part 33 is deformed, the connection between the dynamic pressure part 33 and the abutment part 34 will actually be deformed.

[0069] Reference Figure 3 Preferably, the inner diameter of the fixing ring 41 is larger than the outer diameter of the top foil 3, so that a gap is left between the inner ring of the fixing ring 41 and the outer peripheral wall of the top foil 3 to form a hollow part, thereby reducing the interference of the fixing ring 41 on the deformation of the top foil 3. The distance between the two sides of the support member 42 gradually increases in the direction away from the axis of the fixing ring 41, so that the area of ​​the support surface 421 gradually increases in the direction away from the axis of the fixing ring 41.

[0070] Reference Figure 4 and Figure 5 It can be understood that the degree of support provided by the support member 42 to the top foil 3 is related to the contact area between the support member 42 and the abutment portion 34; as the area of ​​the support surface 421 increases, the contact area between the support member 42 and the abutment portion 34 increases, so that the degree of support provided by the support member 42 to the top foil 3 will also be greater. Therefore, the degree of support provided by the support member 42 to the top foil 3 will gradually increase along the radial direction of the bearing as a whole, which is equivalent to that the difficulty of forming the dynamic pressure portion 33 will also gradually increase along the radial direction of the bearing as a whole.

[0071] Reference Figure 5 The pressure of the dynamic pressure air film is related to the speed of air flow; as the radius of the thrust plate 2 increases, the linear velocity of the corresponding area on the thrust plate 2 increases, and the kinetic energy of the dynamic pressure air film in this area also increases. Therefore, the pressure of the dynamic pressure air film will gradually increase along the radial direction of the bearing as a whole.

[0072] Reference Figure 4 and Figure 5 When the dynamic pressure air film is just beginning to be generated, the dynamic pressure air film is located at a position with a smaller radius of the thrust plate 2. Since the dynamic pressure portion 33 is relatively easy to deform, the dynamic pressure portion 33 can be deformed in time under the action of the dynamic pressure air film pressure; and the dynamic pressure portion 33 gradually expands the deformation range, and the dynamic pressure air film gradually expands the pressure action range at the same time, and the deformation difficulty of the dynamic pressure portion 33 will gradually increase, so as to prevent the dynamic pressure portion 33 from being excessively deformed, and reduce the risk of the dynamic pressure portion 33 vibrating violently due to the influence of pressure due to the small deformation difficulty, and at the same time lock the dynamic pressure air film, reduce Slow down the leakage rate of gas; when the dynamic pressure air film is fully formed, as the pressure of the dynamic pressure air film gradually increases along the radial direction of the bearing, the support degree of the support member 42 on the resistance part 34 also gradually increases along the radial direction of the bearing, and the deformation difficulty of the dynamic pressure part 33 also gradually increases along the radial direction of the bearing, so that the dynamic pressure part 33 can generate a gap through deformation to ensure that the dynamic pressure air film can be stably generated, while also being able to maintain stability and reduce the risk of excessive deformation, ensuring that the dynamic pressure air film can work stably, so that the deformation of the dynamic pressure part 33 reaches a good balance.

[0073] Reference Figure 3 In this embodiment, the top foil 3 is designed to be easy to deform and to recover after being unaffected by the dynamic pressure film. Therefore, the mechanical strength of the top foil 3 is very important, and the mechanical strength of the top foil 3 is directly related to the thickness of the top foil 3. Preferably, the top foil 3 is made of beryllium bronze material, and the thickness of the top foil 3 is 0.3 mm; in other embodiments, the user can also change the thickness of the top foil 3 according to actual needs.

[0074] Reference Figure 3 and Figure 4 , because the pilot air pit 35 of the top foil 3 itself and the depressed dynamic pressure part 33 can both open the distance between the top foil 3 and the thrust plate 2 to allow the dynamic pressure air film to form quickly, the action of opening the gap does not require the support member 42 of the supporting structure to provide deformation itself; the top support frame 4 is in direct contact with the top foil 3 over a large area, and a large part of the heat of the top foil 3 will be quickly transferred to the top support frame 4. The top support frame 4 also has the function of sharing the heat of the top foil 3. Therefore, the top support frame 4 requires a higher mechanical strength and better heat dissipation performance. Preferably, the top support frame 4 is made of SS304 steel, and the thickness of the top support frame 4 is 1 mm; in other embodiments, the user can also change the thickness or material of the top support frame 4 according to actual needs.

[0075] Reference Figure 3 The reinforcement component 5 is arranged on the side of the top support frame 4 away from the top foil 3. The reinforcement component 5 has the functions of supporting the top support frame 4 and adjusting the maximum displacement of the top foil 3 in the axial direction of the bearing. Preferably, the number of the reinforcement components 5 is 2, and the two reinforcement components 5 are superimposed along the axial direction of the bearing. In other embodiments, the user can change the number of the reinforcement components 5 according to actual needs, that is, the number of the reinforcement components 5 is at least 1.

[0076] Reference Figure 1 and Figure 3 Each group of reinforcement components 5 includes a load adjustment plate 51 and a load frame 7 for supporting the adjustment plate, and for the same group of reinforcement components 5, the load frame 7 is arranged on the side of the load adjustment plate 51 away from the top support frame 4. The load adjustment plate 51 is in an annular shape as a whole, and the outer diameter of the load adjustment plate 51 is consistent with the outer diameter of the top foil 3, so that the support area of ​​the load adjustment plate 51 on the top support frame 4 corresponds to the support area of ​​the top support frame 4 on the top foil 3; the inner diameter of the load adjustment plate 51 is larger than the inner diameter of the top foil 3 to reduce the mechanical friction between the load adjustment plate 51 and the rotating shaft 1. The load adjustment plate 51 is integrally formed with a plurality of third positioning members 511 corresponding to each limiting groove 621, and each third positioning member 511 is arranged along the radial direction of the bearing, and each first positioning member 36 is inserted into the corresponding limiting groove 621, so that the load adjustment plate 51 is fixed in the retaining frame 62.

[0077] Reference Figure 3 The load frame 7 includes a connecting ring 71 installed in the retaining frame 62, and a load member 72 installed in the connecting ring 71, wherein the outer diameter and inner diameter of the connecting ring 71 are consistent with the outer diameter and inner diameter of the fixing ring 41. The outer peripheral wall of the connecting ring 71 is provided with a plurality of fourth positioning members 74 corresponding to each of the limiting grooves 621, each of which is arranged along the radial direction of the bearing and is inserted into the corresponding limiting groove 621.

[0078] Reference Figure 3 , each load member 72 is distributed along the inner ring of the connecting ring 71 at intervals, each load member 72 points to the axis of the connecting ring 71, and a second clearance space 73 is formed between two adjacent load members 72, and the maximum length of the load member 72 in the radial direction of the bearing is slightly smaller than the inner diameter difference between the connecting ring 71 and the top foil 3. Preferably, a side of the load member 72 away from the bearing seat 61 forms a force-bearing surface 721, and the distance between the two sides of the load member 72 gradually increases toward the axis of the connecting ring 71, so that the area of ​​the force-bearing surface 721 gradually increases toward the axis of the connecting ring 71. In this embodiment, each fourth positioning member 74 and each load member 72 are integrally formed with the connecting ring 71.

[0079] Reference Figure 3 Preferably, the number of load members 72 provided on the same connecting ring 71 corresponds to the number of support members 42 provided on the fixing ring 41, and the load members 72 on the connecting ring 71 are staggered with the support members 42 on the adjacent fixing ring 41 and / or the load members 72 on other adjacent connecting rings 71.

[0080] For the convenience of description, the reinforcement component 5 close to the top support frame 4 is defined as the reinforcement component 5a, and the reinforcement component 5 far from the top support frame 4 is defined as the reinforcement component 5b; wherein the load adjustment plate 51a, the load member 72a and the second clearance space 73a all correspond to the reinforcement component 5a; the load adjustment plate 51b, the load member 72b and the second clearance space 73b all correspond to the reinforcement component 5b.

[0081] Reference Figure 6 , each load member 72a is staggered with each support member 42, and the position of each load member 72b corresponds to the position of each support member 42, so that each load member 72a is staggered with each load member 72b; any first clearance space 43 has an overlapping part with a load member 72a and a second clearance space 73b in the axial direction of the bearing.

[0082] Reference Figure 6 When the top foil 3 is subjected to the pressure of the dynamic pressure gas film, the top foil 3 as a whole applies an axial force of the bearing to each support member 42 in the direction away from the thrust plate 2, and each support member 42 applies a force in the same direction to the load adjustment plate 51a, and the load adjustment plate 51a applies a force in the same direction to each load member 72a, and each load member 72a applies a force in the same direction to the load adjustment plate 51b, and the load adjustment plate 51b applies a force in the same direction to each load member 72b, thereby making the top support frame 4, reinforcement assembly 5a and reinforcement assembly 5b pressed tightly in sequence.

[0083] Reference Figure 6 and Figure 7 It can be understood that when each support member 42 is pressed against the load adjustment plate 51a, since the pressure of the dynamic pressure air film gradually increases along the radial direction of the bearing, the pressure of the support member 42 on the load adjustment plate 51a will also gradually increase along the radial direction of the bearing. When each load member 72a contacts the load adjustment plate 51a, since the area of ​​the force-bearing surface 721 gradually increases along the radial direction of the bearing, the support force of the load member 72a on the load adjustment plate 51a will also gradually increase along the radial direction of the bearing. Therefore, after the dynamic pressure air film is formed, the support member 42 and the load member 72a act on the two sides of the load adjustment plate 51a respectively, and the force of the support member 42 and the support force of the load member 72a both gradually increase along the radial direction of the bearing, thereby achieving a balanced and stable support state, making the top support frame 4 more stable.

[0084] Reference Figure 5and Figure 6 At the same time, since the supporting force of the load member 72a on the load adjustment plate 51a gradually increases along the radial direction of the bearing, the pressure of the load adjustment plate 51a on the load member 72a will gradually increase along the radial direction of the bearing, causing the supporting force of the load member 72a on the load adjustment plate 51b to gradually increase along the radial direction of the bearing.

[0085] Reference Figure 6 and Figure 7 When each load member 72b is pressed against the load adjustment plate 51b, since the area of ​​the force-bearing surface 721 gradually increases along the radial direction of the bearing, the support force of the load member 72b on the load adjustment plate 51b will also gradually increase along the radial direction of the bearing. Therefore, after the dynamic pressure air film is formed, the load member 72a and the load member 72b act on the two sides of the load adjustment plate 51b respectively, and the force of the load member 72a and the support force of the load member 72b both gradually increase along the radial direction of the bearing, thereby achieving a balanced and stable support state, making the load adjustment plate 51a more stable.

[0086] Reference Figure 6 On the other hand, since the load members 72a are staggered with the support members 42, the portion of the load adjustment plate 51a pressed against the load member 72a can be slightly recessed in the direction of entering the first clearance space 43, while the portion of the load adjustment plate 51a pressed against the support member 42 can be slightly recessed in the direction of entering the second clearance space 73a, thereby allowing the top support frame 4 and the top foil 3 to move a certain distance along the bearing axis as a whole.

[0087] Reference Figure 6 Similarly, since the load members 72a and the load members 72b are staggered, the portion of the load adjustment plate 51b that is pressed against the load member 72a can be slightly depressed toward the direction of entering the second clearance space 73b, and the portion of the load adjustment plate 51b that is pressed against the load member 72b can be slightly depressed toward the direction of entering the second clearance space 73a, so that the reinforcement component 5a, the top support frame 4 and the top foil 3 can move a certain distance along the bearing axis as a whole. It can be understood that when the top support frame 4, the reinforcement component 5a and the reinforcement component 5b are not in a state of being pressed against each other, the load adjustment plate 51a and the load adjustment plate 51b will restore their deformation.

[0088] Reference Figure 4 and Figure 6, the load adjustment plate 51a and the load adjustment plate 51b both utilize the method of being deformed after being pressed together, which provides the top support frame 4 and the top foil 3 with the freedom to undergo a slight displacement in the axial direction of the bearing. After the dynamic pressure air film is fully formed, the top foil 3 as a whole can be slightly away from the thrust plate 2, so that the dynamic pressure air film located in the gap between the thrust plate 2 and each dynamic pressure part 33 can be connected, so that the dynamic pressure air film can fully act on the top foil 3. Due to the influence of the deformation of the dynamic pressure part 33, part of the contact part 34 may also undergo a certain deformation. After the dynamic pressure air film fully acts on the top foil 3, the dynamic pressure air film passes through the surface of the contact part 34, separating the contact part 34 from the thrust plate 2, thereby reducing the risk of mechanical contact between the contact part 34 and the thrust plate 2.

[0089] Reference Figure 6 Preferably, in order to make the gaps formed by the staggered distribution between the first clearance space 43, the second clearance space 73a and the second clearance space 73b more uniform and reasonable, the range of the angle formed between the two sides of the first clearance space 43 and the range of the angle formed between the two sides of the second clearance space 73 are both -0.1° to 0.1°. In this embodiment, the two sides of the first clearance space 43 are almost parallel to each other, and the two sides of the second clearance space 73 are also almost parallel to each other. Further, in order to make the distribution of the recessed parts on the load adjustment plate 51 more uniform, the maximum arc length of the first clearance space 43 corresponding to the axis of the bearing body is 1.5 to 2.5 times the maximum arc length of the support member 42 corresponding to the axis of the bearing body; the maximum arc length of the second clearance space 73 corresponding to the axis of the bearing body is 1.5 to 2.5 times the maximum arc length of the load member 72 corresponding to the axis of the bearing body. In this embodiment, the maximum arc length of the first clearance space 43 is twice the maximum width of the support member 42 ; the maximum arc length of the second clearance space 73 is twice the maximum width of the load member 72 .

[0090] Reference Figure 3 In the embodiment, the load frame 7 and the load adjustment plate 51 are both made of SS304 steel, wherein the thickness of the load frame 7 is 1 mm, and the thickness of the load adjustment plate 51 is 0.5 mm; in other embodiments, the user may also change the thickness of the load frame 7 or the load adjustment plate 51 according to actual needs.

[0091] The implementation principle of a thrust foil air bearing in the embodiment of the present application is as follows: when the rotating shaft 1 drives the thrust disc 2 to start rotating, the air between the thrust disc 2 and the pilot air pit 35 gradually increases the kinetic energy and gradually forms a dynamic pressure air film. When the dynamic pressure air film is just beginning to form, the dynamic pressure air film has a relatively small force on the top foil 3. At this time, since the support degree of the support member 42 on the top foil 3 is also relatively weak, the part of the dynamic pressure part 33 close to the pilot air pit 35 is prone to deformation. Therefore, even if the dynamic pressure air film has a relatively small force, the dynamic pressure air film can push the dynamic pressure part 33 and make the dynamic pressure part 33 gradually concave, thereby timely increasing the width of the gap between the dynamic pressure part 33 and the thrust disc 2, so that the dynamic pressure air film can be formed more quickly and stably. At the same time, the concave part of the dynamic pressure part 33 can timely separate the inner ring of the top foil 3 from the outer peripheral wall of the rotating shaft 1, and the load provided by the dynamic pressure air film can timely suspend the rotating shaft 1 in the inner ring of the top foil 3, so as to achieve the effect of reducing the takeoff speed of the thrust foil air bearing.

[0092] During the gradual formation of the dynamic pressure air film, the pressure of the dynamic pressure air film will gradually increase along the radial direction of the bearing. Since the degree of support of the support member 42 to the resistance part 34 also gradually increases along the radial direction of the bearing, a balance can be formed between the top foil 3 and the dynamic pressure air film, in which the greater the force of the dynamic pressure air film, the greater the difficulty of deformation of the top foil 3, so as to reduce the risk of excessive deformation of the top foil 3, lock the dynamic pressure air film, slow down the leakage rate of gas, and improve the working stability of the dynamic pressure air film.

[0093] After the dynamic pressure air film is gradually and stably formed, the pressure applied by the dynamic pressure air film on the top foil 3 gradually reaches the maximum. Based on the freedom provided by the reinforcement component 5, the top foil 3 and the top support frame 4 can be slightly displaced away from the thrust plate 2, so that the dynamic pressure air film can act completely on the top foil 3, so that the thrust foil air bearing can work more stably.

[0094] In addition, the pressure applied by the dynamic pressure air film to the top foil 3 is smaller at the smaller diameter and reaches a peak at the largest diameter, while the area of ​​the support surface 421 of the support member 42 on the top foil 3 increases with the increase of the diameter, so that the force on the top foil 3 tends to be balanced in both the axial direction and the radial direction of the bearing, and is more stable. Similarly, the pressure applied by the top support frame 4 or the load adjustment plate 51 to the load member 72 is smaller at the smaller diameter and reaches a peak at the largest diameter, while the area of ​​the support surface 421 of the load member 72 on the top support frame 4 or the load adjustment plate 51 increases with the increase of the diameter, so that the force on the top support frame 4 or the load adjustment plate 51 tends to be balanced in both the axial direction and the radial direction of the bearing, thereby making the operation of the thrust foil air bearing more stable.

[0095] Furthermore, by utilizing the characteristics that the top foil 3 is easy to deform at the place with smaller inner diameter and the top foil 3 can form a gap with the thrust plate 2 through the pilot air pit 35, the top foil 3 can be attached to the thrust plate 2, thereby reducing the minimum distance between the thrust foil air bearing and the thrust plate 2 in the axial direction of the bearing and improving space utilization.

[0096] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A thrust foil air bearing capable of being rotatably connected to a rotating shaft (1) and cooperating with a thrust disk (2), characterized in that: The thrust foil air bearing comprises a top foil (3) that can be arranged on one side of the thrust plate (2), a top support frame (4) for supporting the top foil (3), and a fixing assembly (6) for fixing the top foil (3) and the top support frame (4); The top support frame (4) comprises at least two support members (42) arranged on a side of the top foil (3) away from the thrust plate (2), the support members (42) being spaced apart so that a first clearance space (43) is provided between two adjacent support members (42); the top foil (3) is provided with a dynamic pressure portion (33) corresponding to each of the first clearance spaces (43); The top foil (3) can abut against each support member (42) in a working state, so that the dynamic pressure portion (33) is recessed in a direction corresponding to the first clearance space (43), and a gap capable of accommodating the air film is formed between the dynamic pressure portion (33) and the thrust plate (2); The top foil (3) is provided with a connection hole (31) for the rotating shaft (1) to pass through, the top foil (3) is attached to the thrust plate (2), and a pilot gas pit (35) for accommodating gas is provided on a side of the top foil (3) away from the thrust plate (2), the pilot gas pit (35) being connected to the connection hole (31); A slight height difference is formed between the pit mouth and the pit bottom of the pilot air pit (35); the height difference enables the gas to enter between the top foil (3) and the thrust plate (2) through the gap between the pilot air pit (35) and the thrust plate (2) when the top foil (3) is attached to the thrust plate (2), so that the dynamic pressure air film is gradually deformed.

2. The thrust foil air bearing according to claim 1, characterized in that: The support member (42) is provided with a support surface (421) for contacting the top foil (3), and the area of ​​the support surface (421) gradually increases in a direction away from the geometric center of the top support frame (4).

3. The thrust foil air bearing according to claim 1, characterized in that: The top support frame (4) further comprises a fixing ring (41) connected to the fixing assembly (6), the fixing ring (41) being coaxial with the top foil (3), and the supporting members (42) being circumferentially distributed on the inner ring of the fixing ring (41).

4. The thrust foil air bearing according to any one of claims 1 or 3, characterized in that: The pilot air pits (35) are arranged on a side of the dynamic pressure portion (33) close to the connecting hole (31), so that the pilot air pits (35) are distributed in a circular pattern around the connecting hole (31).

5. The thrust foil air bearing according to claim 1, characterized in that: The invention also comprises at least one group of reinforcing components (5) arranged on a side of the top support frame (4) away from the top foil (3), wherein the reinforcing components (5) comprise a load adjustment plate (51) and a load frame (7) for supporting the load adjustment plate (51), wherein the load frame (7) is arranged on a side of the load adjustment plate (51) away from the top support frame (4), and the load adjustment plate (51) is capable of contacting an adjacent top support frame (4) and / or a load frame (7) adjacent to other reinforcing components (5).

6. The thrust foil air bearing according to claim 5, characterized in that: The load frame (7) comprises at least two load members (72) arranged on a side of the top support frame (4) away from the top foil (3); the load members (72) are spaced apart so that a second clearance space (73) is provided between two adjacent load members (72); Each second clearance space (73) on any of the load racks (7) has an overlapping portion with the support member (42) on the adjacent top support rack (4) and / or the load member (72) on the adjacent load rack (7).

7. The thrust foil air bearing according to claim 6, characterized in that: The number of the load members (72) corresponds to the number of the support members (42); the load members (72) on any one of the load racks (7) are staggered with the support members (42) on the top support rack (4) and / or the load members (72) on other adjacent load racks (7).

8. The thrust foil air bearing according to claim 6, characterized in that: The area of ​​a side of the load-bearing member (72) close to the top support frame (4) gradually increases in a direction away from the geometric center of the load frame (7).

9. The thrust foil air bearing according to claim 6, characterized in that: The angle formed between the two sides of the first clearance space (43) and / or the two sides of the second clearance space (73) is -0.1° to 0.1°; the maximum arc length of the first clearance space (43) is 1.5 to 2.5 times the maximum width of the support member (42); and the maximum arc length of the second clearance space (73) is 1.5 to 2.5 times the maximum width of the load member (72).

10. The thrust foil air bearing according to claim 1, characterized in that: The fixing assembly (6) comprises a bearing seat (61) and a retaining frame (62) detachably connected to the bearing seat (61); the top support frame (4) and the top foil (3) are both arranged in the retaining frame (62); the inner ring of the retaining frame (62) has at least two limiting grooves (621) for positioning the top foil (3) and / or the top support frame (4); the top foil (3) is provided with a first positioning member (36) for plugging into the limiting groove (621); and the top support frame (4) is provided with a second positioning member (411) for plugging into the limiting groove (621).

11. The thrust foil air bearing according to claim 10, characterized in that: The limiting groove (621) is connected to one side of the retaining frame (62) to form a notch portion (622), and the retaining frame (62) is detachably connected to a retaining ring (63) for covering the notch portion (622) to prevent the first positioning member (36) and / or the second positioning member (411) from escaping from the limiting groove (621).

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