CN111795062B

CN111795062B - Radial foil dynamic pressure air bearing

Info

Publication number: CN111795062B
Application number: CN202010706913.0A
Authority: CN
Inventors: 朱冰硕; 袁添泽; 牛树潭; 刘铭; 陈少华; 陆胜策; 武伟; 张春华; 张康; 牛浩铎
Original assignee: Hebei Kingston Technology Co ltd
Current assignee: Hebei Kingston Technology Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2022-07-29
Anticipated expiration: 2040-07-21
Also published as: CN111795062A

Abstract

The invention discloses a radial foil hydrodynamic air bearing, wherein cutting openings in an interconnected wave foil extend from the inner side of a fixed end to the inner side of a free end, and each cutting opening consists of three sections of independent arc-shaped sub cutting openings. According to the interconnected wave foil, the existing dispersed multiple wavelet foils are mutually connected at different positions in the circumferential direction, so that the dispersed wavelet foils are mutually connected, the wavelet foils at two ends are limited by the middle wavelet foil, and the problem that the dispersed wavelet foils at two ends are easy to dislocate along the axial direction in the use process of the dynamic pressure radial air bearing is solved. Both ends of the top foil are provided with bending structures and are arranged in the slots of the bearing seat, limiting baffle rings are fixed at both ends of the bearing seat and cover both ends of the through groove, and the axial limiting can be carried out on the bending structures, so that the problem that the top foil is dislocated along the axial direction in the use process of the radial foil dynamical pressure air bearing is solved, the stability of the bearing is improved, and the service life of the bearing is prolonged.

Description

Radial foil dynamic pressure air bearing

Technical Field

The invention relates to the field of air bearings, in particular to a radial foil hydrodynamic air bearing.

Background

The foil air bearing is a self-acting dynamic pressure air bearing which adopts air as a lubricating medium, is firstly applied to an environmental control system (ACM) of an airplane in the 70 th century, is gradually popularized to the fields of small turbojet engines, turbine refrigerators, micro gas turbines and the like in the eighty and ninety years, and is further applied and developed to the fields of air suspension centrifugal blowers, electronic turbochargers, compressors for hydrogen fuel cells and the like in the 21 st century. Compared with the traditional high-speed bearing, the foil air bearing has the advantages of simple structure, high rotating speed, low friction power consumption, high and low temperature resistance, good stability, convenience in maintenance and the like, and has wide application prospects in the field of future high-speed rotating machinery.

Generally, a radial foil hydrodynamic air bearing is composed of a top foil and a bump foil, the bump foil is arranged in an inner hole of a bearing seat and is jointed with the inner hole wall of the bearing seat along the circumferential direction, and the top foil is arranged in the bump foil and is jointed with the bump foil along the circumferential direction. The top foil and the wave foil are not closed along the circumferential direction and are in an open structure, wherein one end of the top foil is called a free end, and the other end of the top foil is called a fixed end.

From the installation mode of radial foil dynamical pressure air bearing, the fixed end is restrained on the bearing seat completely, and can not move freely along the circumferential direction or the axial direction, and for the top foil, the free end is not restrained, and the free end of the top foil can move in a small range along the circumferential direction, which is necessary for the normal work of the radial foil dynamical pressure air bearing.

The free end of the top foil may also be displaced in axial direction, i.e. the top foil may be axially misaligned. When the foil dynamical pressure air bearing works normally, the free end area of the top foil cannot be influenced by axial vibration of a shaft system, the top foil is easy to dislocate along the axial direction, and meanwhile, due to the fact that the top foil is in close contact with the wave foil, the free end of the wave foil is easy to dislocate along the axial direction due to the existence of friction between the top foil and the wave foil.

In addition, as shown in fig. 1 and 2, the conventional wave foil X20 has a structure in which one or more cuts are formed in the wave foil X20, the cuts penetrate the free end of the wave foil from the fixed end thereof, the wave foil main body is divided into a plurality of sub-wave foils in the axial direction, the sub-wave foils are connected to each other only by the fixed end, and the sub-wave foils at both ends are more likely to be displaced in the axial direction due to the small pressure of the gas film and the vibration effect during operation.

The dislocation of the foil can lead the effective working gas film in the bearing area to be unevenly distributed, reduce the bearing capacity and stability of the foil hydrodynamic air bearing, and lead the shafting to be unstable in operation, aggravate vibration and even possibly cause shafting burning loss in severe cases. At present, no effective method for solving the problem of axial dislocation of the foils of the radial foil dynamical pressure air bearing exists.

Disclosure of Invention

The invention aims to solve the technical problem of providing a radial foil dynamic pressure air bearing capable of effectively preventing axial displacement of a foil.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

the utility model provides a radial foil dynamic pressure air bearing, includes bearing frame, ripples foil and the top foil of nesting in proper order from outer to interior, its characterized in that:

the bearing seat is provided with a through groove on the inner wall along the axial direction of the bearing seat, and a spacer block which divides the through groove into a first slot and a second slot in the circumferential direction is arranged in the through groove;

the corrugated foil is provided with one circumferential or a plurality of circumferential cutting openings in the axial direction, each cutting opening extends from the inner side of the fixed end to the inner side of the free end and consists of three sections of independent arc-shaped sub cutting openings;

the two ends of the top foil are respectively bent towards the centrifugal direction to form a fixed flange and a movable flange;

the fixed flanging is attached to the wing to form a fixed part and is inserted into the first slot, the movable flanging is inserted into the second slot and is arranged close to the spacer block, and an annular movable gap for the movable part to move away from the spacer block is formed in the second slot;

The bearing seat further comprises two limiting baffle rings which are fixed at two ends of the bearing seat and can limit the axial movement of the fixing part and the movable flanging.

The further technical scheme is as follows: the outer end of the first slot is provided with a positioning groove which is right-angled and communicated with the first slot, the tail end of the top foil fixing flange is also provided with a positioning flange which is right-angled with the top foil fixing flange, the positioning flange is arranged in the positioning groove and is attached to the inner side wall of the positioning groove, and a radial movable gap for the outward movement of the positioning flange is formed in the positioning groove.

The further technical scheme is as follows: the sub-cuts at both ends are symmetrically arranged, and the length of the sub-cut at each end is 1/4 of the wave foil circumference.

The further technical scheme is as follows: the fixing part is inserted into the first slot and then clings to the spacer block, and a self-adaptive gap for the fixing part to move away from the spacer block is formed in the first slot.

The further technical scheme is as follows: the self-adaptive gap is 0.5-1.5 mm.

The further technical scheme is as follows: the bearing seat is characterized in that two end faces of the bearing seat are provided with outward-expanding annular grooves, the limiting baffle rings are elastic baffle rings and are embedded in the annular grooves, and the through grooves are partially or completely covered.

The further technical scheme is as follows: two ends of the inner edge of the bearing seat extend outwards to form guide rings; the lower parts of the two ends of the spacing block, the fixed part and the movable flanging extend outwards into the guide ring, so that two ends of the spacing block, the fixed part and the movable flanging form a right-angled notch; the limiting baffle ring is sleeved on the guide ring, and the end face of the inner side of the limiting baffle ring is attached to the end face of the outer edge of the bearing seat and is fixed with the bearing seat.

The further technical scheme is as follows: the limiting blocking ring is fixedly connected with the bearing seat through a plurality of screws which are circumferentially and uniformly distributed, and a screw counter bore is formed in the limiting blocking ring.

The further technical scheme is as follows: the outer wall of the guide ring is provided with external threads, and the limiting baffle ring is in threaded connection with the guide ring to realize fixation with the bearing seat.

The further technical scheme is as follows: the inner edge of the end face of the outer side of the limit retaining ring extends inwards to form an outer locating ring, and the outer locating ring can axially limit the bump foil.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in:

the radial foil dynamic pressure air bearing applies the interconnected wave foils, the interconnected wave foils enable the dispersed wavelet foils to be interconnected together by mutually connecting the existing dispersed wavelet foils at different positions in the circumferential direction, the wavelet foils at two ends are restricted by the middle wavelet foil, the problem that the dispersed wavelet foils at two ends are easy to dislocate along the axial direction in the use process of the dynamic pressure radial air bearing is solved, and the stability of the radial dynamic pressure air bearing applying the interconnected wave foils in the use process is improved.

Both ends of the top foil are provided with bending structures and are arranged in the slots of the bearing seat, limiting baffle rings are fixed at both ends of the bearing seat and cover both ends of the through groove, and the axial limiting can be carried out on the bending structures, so that the problem that the top foil is dislocated along the axial direction in the use process of the radial foil dynamical pressure air bearing is solved, the stability of the bearing is improved, and the service life of the bearing is prolonged.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic diagram of a prior art wave foil configuration;

FIG. 2 is a schematic view of a prior art unfolded structure of a bump foil;

FIG. 3 is a schematic diagram of an interconnect-type bump foil according to the present invention;

FIG. 4 is a schematic diagram of an expanded structure of the interconnected wave foils of the present invention;

FIG. 5 is a schematic structural view of a fifth embodiment of a radial foil hydrodynamic air bearing of the present disclosure;

FIG. 6 is a schematic front view of the elastic collar shown in FIG. 5 without the elastic collar;

FIG. 7 is a schematic view of a top foil configuration in a radial foil dynamical pressure air bearing according to the present disclosure;

FIG. 8 is a schematic structural view of a sixth embodiment of a radial foil hydrodynamic air bearing of the present disclosure;

FIG. 9 is a schematic view of the retainer ring of FIG. 8 shown without the retainer ring;

FIG. 10 is a schematic front view of the retainer ring of FIG. 8 shown without the retainer ring;

FIG. 11 is another schematic diagram of a top foil configuration in a radial foil hydrodynamic air bearing of the present disclosure;

FIG. 12 is a schematic view of a wave foil configuration in a radial foil hydrodynamic air bearing of the present disclosure;

FIG. 13 is a schematic diagram of a ninth embodiment of a radial foil hydrodynamic air bearing of the present disclosure;

FIG. 14 is a schematic view of a positive stop ring of an embodiment nine of the radial foil hydrodynamic air bearing of the present disclosure;

fig. 15 is a schematic front view of an embodiment of a radial foil hydrodynamic air bearing of the present disclosure with the retainer ring removed.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Example one

As shown in fig. 3 and 4, an interconnected wave foil is provided with a circumferential curl, one end of the wave foil 20 is a fixed end and has a wing 21 formed by bending toward a centrifugal direction, and the other end extends circumferentially to form a free end, the wave foil 20 has one or more circumferential cuts in an axial direction, and the interconnected wave foil is characterized in that: the cutting opening extends from the inner side of the fixed end to the inner side of the free end; the cutting opening is composed of three sections of independent arc-shaped sub cutting openings 22; the sub-cuts 22 at both ends are symmetrically arranged, and the length of the sub-cut 22 at each end is 20-30%, preferably 25%, of the circumference of the corrugated foil 20.

The interconnected wave foil interconnects the dispersed wavelet foils at different circumferential positions, the wavelet foils at two ends are restricted by the middle wavelet foil, the problem that the dispersed wavelet foils at two ends are easy to dislocate along the axial direction in the use process of the radial dynamic pressure air bearing is solved, and the stability of the radial dynamic pressure air bearing applying the interconnected wave foil in use is improved.

In addition, the lengths of the sub cuts 22 at the two ends are 20% -30% of the circumference of the corrugated foil 20, so that the two adjacent sections of the corrugated foils have connection points at the two ends in the circumferential direction and the positions left and right from the end 1/4, and the rigidity and deformation requirements of the foils are met. Generally, after the bearing is installed, the main bearing area is in the area of the middle 1/3, and in order to ensure that the wave foils in the middle area can be freely deformed and the wave foils can be connected with each other, the connection points are selected to be arranged at positions around 1/4.

Example two

As shown in fig. 5 to 14, an embodiment of a radial foil dynamical pressure air bearing according to the present disclosure includes a bearing seat 10, a bump foil 20, and a top foil 30, which are sequentially nested from the outside to the inside. The bearing seat 10 is manufactured by machining, and the wave foil 20 and the top foil 30 are manufactured by cutting and blanking with laser, hydraulic forming with a die and rolling with a rolling machine. The bump foil 20 is corrugated and includes a bump contacting the top foil 30 and a horizontal connecting section contacting the inner surface of the bearing housing 10, and the bump foil 20 is an elastic supporting member capable of providing elastic support to the top foil 30. When the rotor runs at a high speed, due to the periodic action of the wedge-shaped compressed air film force between the top foil 30 and the rotor, the wavy foil 20 can generate tiny elastic deformation under the action of the air film force and generate tiny sliding with the inner surfaces of the top foil 30 and the bearing seat 10, so that sufficient damping is provided for the high-speed running of the bearing, and the running stability of the rotor is ensured.

The bump foil 20 is arranged along the circumferential direction of an inner hole of the bearing seat 10 in a curling mode and is nested between the bearing seat 10 and the top foil 30, one end of the bump foil 20 is a fixed end and is provided with a wing 21 formed by bending towards the centrifugal direction, and the other end of the bump foil extends in the circumferential direction to form a gap between a free end and the fixed end and is not closed. The corrugated foil 20 is provided with one or more circumferential cutting openings in the axial direction, each cutting opening extends from the inner side of the fixed end to the inner side of the free end and consists of three sections of independent arc-shaped sub cutting openings 22; the sub-cuts 22 at both ends are symmetrically arranged, and the length of the sub-cut 22 at each end is 20-30% of the circumference of the bump foil 20.

The wave foils 20 of the radial foil dynamic pressure air bearing adopt an interconnection type structure, the interconnection type wave foils enable the dispersed wavelet foils to be interconnected together by mutually connecting a plurality of existing dispersed wavelet foils at different positions in the circumferential direction, the wavelet foils at two ends are restricted by the middle wavelet foil, the problem that the dispersed wavelet foils at two ends are easy to dislocate along the axial direction in the use process of the dynamic pressure radial air bearing is solved, and therefore the stability of the radial dynamic pressure air bearing applying the interconnection type wave foils in the use process is improved.

In addition, the lengths of the sub cuts 22 at the two ends are 20% -30% of the circumference of the corrugated foil 20, so that the two adjacent sections of the corrugated foils have connection points at the two ends in the circumferential direction and the positions left and right from the end 1/4, and the rigidity and deformation requirements of the foils are met.

Example two

According to one embodiment of the disclosed radial foil dynamical pressure air bearing, a through groove is formed on the inner wall of the bearing seat 10 along the axial direction thereof, and a spacer 12 is disposed in the through groove and divides the through groove into a first slot 13 and a second slot 14 in an annular direction.

The top foil 30 is arranged along the circumferential direction of an inner hole of the bearing seat 10 in a curling manner and is nested in the bearing seat 10, and two ends of the top foil 30 are respectively bent towards the centrifugal direction to form a fixed flange 31 and a movable flange 32; the fixed flanging 31 is attached to the wing 21 to form a fixed portion and inserted into the first slot 13, the movable flanging 32 is inserted into the second slot 14 and is arranged close to the spacer block 12, a circumferential movable gap for enabling the movable portion to move away from the spacer block 12 is formed in the second slot 14, the circumferential movable gap is preferably 1.5-2.5 mm, and deformation is provided for the foil. The fixed and movable flanges 32 are also left radially deformed by the displacement in the corresponding slots.

And limiting stop rings 40 capable of limiting the axial movement of the fixing part and the movable flange 32 are fixed at two ends of the bearing seat 10.

In the air bearing, the two ends of the top foil 30 are respectively provided with a bending structure and are arranged in the slots of the bearing seat 10, and the bending structures are axially limited through the limiting baffle ring 40, so that the problem that the top foil 30 is axially staggered in the use process of the radial foil dynamic pressure air bearing is solved, and the arrangement of the interconnected wave foils is matched, so that the stability of the bearing is improved, and the service life of the bearing is prolonged.

Example four

According to one embodiment of the disclosed radial foil dynamical pressure air bearing, the fixing part is inserted into the first slot 13 and then arranged close to the spacer 12, and the first slot 13 is provided with a self-adaptive gap for the fixing part to move away from the spacer 12. The self-adaptive gap is 0.5-1.5 mm, and the optimal value is 1 mm. Because the fixed ends of the top foil 30 and the bump foil 20 can also move freely in a small range along the circumferential direction, the fixed ends have a small adjustment amount rotating along with the rotor at the initial movement, and the self-adaptability and the stability of the bearing are further improved.

EXAMPLE five

According to an embodiment of the disclosed radial foil dynamical pressure air bearing, as shown in fig. 5 and 6, the bearing seat 10 has outwardly-expanding annular grooves 15 on both end surfaces, and the limit stop ring 40 is an elastic stop ring and is embedded in the annular groove 15 to partially or completely cover the through groove. The circlip is the standard component, and ring channel 15 internal diameter slightly is less than the external diameter of circlip, and the degree of depth of ring channel 15 slightly is greater than the thickness of circlip, and the circlip can tightly paste on the inner wall of ring channel 15 after the installation to play the axial and the hoop limiting displacement to the circlip, prevent that the circlip from transmitting and turn over a section production friction with the foil, and drive the foil displacement.

Example six

According to an embodiment of the disclosed radial foil dynamical pressure air bearing, as shown in fig. 8 to 12, guide rings 16 are formed by extending both ends of the inner edge of the bearing seat 10; the lower parts of the two ends of the spacing block 12, the fixed part and the movable flanging 32 extend outwards into the guide ring 16, so that two ends of the spacing block 12, the fixed part and the movable flanging 32 form a right-angled notch 33; the limiting stop ring 40 is sleeved on the guide ring 16, and the end surface of the inner side of the limiting stop ring is attached to the end surface of the outer edge of the bearing seat 10 and fixed with the bearing seat 10. The guide ring 16 plays a role in guiding and positioning for installation of the limit stop ring 40, and the limit stop ring 40 is clamped at the opening 33 of the top foil 30 after being installed in place, so that axial movement of the top foil 30 can be limited.

EXAMPLE seven

According to one embodiment of the disclosed radial foil dynamical pressure air bearing, the limit stop ring 40 is fixedly connected with the bearing seat 10 by means of a plurality of circumferentially and uniformly distributed screws, and screw counter bores are formed in the limit stop ring 40. The screw is not protruded out of the annular cover plate after being installed, so that the screw is prevented from falling off under the action of external force.

Example eight

According to an embodiment of the disclosed radial foil dynamical pressure air bearing, the outer wall of the guide ring 16 is provided with an external thread, and the limit stop ring 40 is connected to the guide ring 16 in a threaded manner to realize fixation with the bearing seat 10.

Example nine

According to an embodiment of the disclosed radial foil dynamical pressure air bearing, as shown in fig. 13 and 14, the inner edge of the outer end surface of the retainer ring 40 extends inward to form an outer positioning ring 41, and the outer positioning ring 41 can axially position the bump foil 20. The outer positioning ring 41 has an inner diameter slightly smaller than that of the bearing seat 10 and larger than that of the bump foil 20, so as to be partially in contact with the end face of the bump foil 20 in the axial direction, thereby blocking the bump foil 20 and axially positioning it, and further preventing the bump foil 20 from being displaced in the axial direction.

Example ten

Because radial foil sheet dynamic pressure air bearing is in the use, when facing some rotating machinery's extreme operating mode, for example, the compressor for hydrogen fuel cell stops under the operating mode at the repetition of high frequency, because the moment of opening and stopping, the dynamic pressure gas film can disappear, the shafting has direct contact with radial foil sheet dynamic pressure air bearing's top foil, also be in the dry friction state, receive the influence of frictional force, radial bearing top foil has the trend of rotating together with the shafting, after opening and stopping repeatedly many times, the first bending of top foil sheet fixed end probably can take place to warp thereby break away from the fixed mounting position of bearing frame, lead to foil sheet dynamic pressure air bearing to become invalid.

According to an embodiment of the disclosed radial foil hydrodynamic air bearing, as shown in fig. 15, the outer end of the first slot 13 is provided with a positioning groove 17 which is perpendicular to and communicated with the first slot, the end of the fixed flange 31 of the top foil 30 is further provided with a positioning flange 34 which is perpendicular to the fixed flange, the positioning flange 34 is arranged in the positioning groove 17 and attached to the inner side wall of the positioning groove, and a radial moving gap for the outward movement of the positioning flange is arranged in the positioning groove.

The fixed end of the top foil 30 is also provided with a positioning flange 34 which is at a right angle with the fixed end, the positioning flange 34 can limit the free movement of the top foil along the radial direction, and can prevent the situation that the fixed part of the top foil 30 is slowly deformed and is pulled out from the first slot 13 to be separated from the bearing seat 10 after the top foil 30 has the tendency of rotating together with a shaft system in the extreme working condition, so that the stability of the mounting state of the top foil can be effectively ensured, and the foil dynamic pressure air bearing can be kept stable and effectively operated.

The above is only a preferred embodiment of the invention, and any simple modifications, variations and equivalents of the invention may be made by anyone in light of the above teachings and fall within the scope of the invention.

Claims

1. A radial foil hydrodynamic air bearing comprises a bearing seat (10), a bump foil (20) and a top foil (30) which are sequentially nested from outside to inside, and is characterized in that:

The bearing seat (10) is provided with a through groove along the axial direction on the inner wall, and a spacer block (12) which divides the through groove into a first slot (13) and a second slot (14) in the circumferential direction is arranged in the through groove;

the corrugated foil (20) is provided with one end which is a fixed end and is provided with a wing (21) formed by bending towards the centrifugal direction, the other end extends in the circumferential direction to form a free end, the corrugated foil (20) is provided with one or more circumferential cutting openings in the axial direction, each cutting opening extends from the inner side of the fixed end to the inner side of the free end and consists of three sections of independent arc-shaped sub cutting openings (22), so that solid connection points are arranged between two circumferentially adjacent sub cutting openings (22) and at two ends of each cutting opening, and the lengths of the sub cutting openings (22) at two ends are 20% -30% of the circumference length of the corrugated foil (20);

the two ends of the top foil (30) are respectively bent towards the centrifugal direction to form a fixed flanging (31) and a movable flanging (32);

the fixed flanging (31) is attached to the wing (21) to form a fixed part, is inserted into the first slot (13) and is arranged close to the spacer block (12), a self-adaptive gap for the fixed part to move away from the spacer block (12) is formed in the first slot (13), the movable flanging (32) is inserted into the second slot (14) and is arranged close to the spacer block (12), and a circumferential movable gap for the movable part to move away from the spacer block (12) is formed in the second slot (14);

The bearing seat further comprises two limiting stop rings (40) which are fixed at two ends of the bearing seat (10) and can limit the fixing part and the movable flanging (32) to move axially.

2. The radial foil hydrodynamic air bearing of claim 1, wherein: the outer end of the first slot (13) is provided with a positioning groove (17) which is at a right angle with the outer end of the first slot and is communicated with the first slot, the tail end of the fixed flange (31) of the top foil (30) is also provided with a positioning flange (34) which is at a right angle with the fixed flange, the positioning flange (34) is arranged in the positioning groove and is attached to the inner side wall of the positioning groove, and a radial movable gap for the outward movement of the positioning flange (34) is formed in the positioning groove.

3. The radial foil hydrodynamic air bearing of claim 1, wherein: the self-adaptive gap is 0.5-1.5 mm.

4. Radial foil hydrodynamic air bearing according to claim 1 or 2, characterized in that: the bearing seat is characterized in that two end faces of the bearing seat (10) are provided with outward-expanded annular grooves (15), the limiting baffle ring (40) is an elastic baffle ring and is embedded in the annular grooves (15), and the through grooves are partially or completely covered.

5. The radial foil hydrodynamic air bearing of claim 1, wherein: two ends of the inner edge of the bearing seat (10) extend outwards to form guide rings (16); the lower parts of the two ends of the spacing block (12), the fixed part and the movable flanging (32) extend outwards into the guide ring (16), so that two ends of the spacing block (12), the fixed part and the movable flanging (32) form a right-angled notch (33); the limiting stop ring (40) is sleeved on the guide ring (16), and the end face of the inner side of the limiting stop ring is attached to the end face of the outer edge of the bearing seat (10) and fixed with the bearing seat (10).

6. The radial foil hydrodynamic air bearing of claim 5, wherein: the limiting blocking ring (40) is fixedly connected with the bearing seat (10) through a plurality of screws which are circumferentially and uniformly distributed, and screw counter bores are formed in the limiting blocking ring (40).

7. The radial foil hydrodynamic air bearing of claim 5, wherein: the outer wall of the guide ring (16) is provided with an external thread, and the limiting stop ring (40) is in threaded connection with the guide ring (16) to realize the fixation with the bearing seat (10).

8. The radial foil hydrodynamic air bearing of claim 5, wherein: the inner edge of the outer side end face of the limit stop ring (40) extends inwards to form an outer locating ring (41), and the outer locating ring (41) can axially limit the bump foil (20).