CN114941650B

CN114941650B - Air bearing without bottom plate

Info

Publication number: CN114941650B
Application number: CN202210525589.1A
Authority: CN
Inventors: 邢子义; 丁晓洁; 王升科; 谢元豪; 赵林亭
Original assignee: Yantai Dongde Industrial Co Ltd
Current assignee: Yantai Dongde Industrial Co Ltd
Priority date: 2022-05-13
Filing date: 2022-05-13
Publication date: 2023-04-28
Anticipated expiration: 2042-05-13
Also published as: CN114941650A

Abstract

The invention relates to an air bearing, in particular to an air bearing without a bottom plate, which comprises a top foil and N wave foil monomers, and is characterized in that one side of each wave foil monomer extends outwards with the same curvature to form M sections of extension bands, and the free end of each extension band is connected with a pull ring into a whole; n groups of M circular truncated cones are formed by upward extension on the end face of the diffuser or the bearing seat, and each group of circular truncated cones is circumferentially arrayed along the axis of the diffuser or the bearing seat; the height of the circular truncated cone is larger than or equal to the thickness of the corrugated foil single body, and M pull rings of each corrugated foil single body are respectively sleeved on 1 group of M circular truncated cones in a gap or transitional manner; the lower surface of the top foil is welded with the top surfaces of N groups of M round tables; n is more than or equal to 3, and M is more than or equal to 2. Compared with the prior art, the invention omits the bottom plate in the prior art, and saves parts and processing cost. The wave foil does not need to be welded, and deformation of the wave foil caused by welding is avoided.

Description

Air bearing without bottom plate

Technical Field

The invention relates to an air bearing, in particular to an air bearing without a bottom plate.

Background

The invention patent of publication number CN112879318A discloses a high-speed centrifugal compressor, and specifically discloses a thrust air bearing which comprises a bottom plate, a middle supporting piece and a top foil, wherein the bottom plate is annular, a plurality of cooling grooves are formed in the circumference of the bottom plate, and a plurality of fixed mounting holes are formed in the outer edge of the bottom plate; the middle supporting piece comprises a plurality of supporting foils and elastic foils, the supporting foils and the elastic foils are fixed on the bottom plate in a spot welding mode, and the supporting foils and the elastic foils are in groups for supporting the top foil; the top foil comprises a plurality of single foils which are arranged in a ring shape, and two adjacent single foils are flexibly connected to form an integral top foil structure.

The invention patent of publication No. CN108286567A discloses a thrust foil dynamic pressure air bearing with a thick top foil structure, which comprises a bottom plate, a supporting wave foil and a top foil, wherein the circular bottom plate is arranged below, a plurality of fan-shaped top foils are fixed above the bottom plate, the supporting wave foil is assembled between the bottom plate and the top foil, the thrust foil dynamic pressure air bearing also comprises an inlet section gasket arranged at one radial side of the joint of the top foil and the bottom plate, the thickness of the inlet section gasket is adjustable, and the supporting wave foil and the top foil are in pre-tightening assembly.

The technical scheme disclosed in the patent comprises a bottom plate, the corrugated foil and the top foil are directly or indirectly connected with the bottom plate, and the bottom plate is fixedly connected on a diffuser or a bearing seat through screws in general, so that limited space is occupied, and the screws are loosened and broken under the action of long-term dynamic load, so that the stability of the whole system of the gas compressor is affected. Moreover, the supporting corrugated foil is easy to deform due to welding, so that the corrugated foil is tilted, and finally uneven top foil and uneven air film are caused during operation.

Disclosure of Invention

In order to overcome the defects or one of the defects in the prior art, the invention discloses an air bearing without a bottom plate, which adopts the following technical scheme:

the utility model provides an air bearing of no bottom plate, includes top foil and N ripples foil monomer, its characterized in that: one side of each corrugated foil single body extends outwards with the same curvature to form M sections of extension bands, and the free end of each extension band is connected with one pull ring into a whole; n groups of M circular truncated cones are formed by upward extension on the end face of the diffuser or the bearing seat, and each group of circular truncated cones is circumferentially arrayed along the axis of the diffuser or the bearing seat; the height of the circular truncated cone is larger than or equal to the thickness of the corrugated foil single body, and M pull rings of each corrugated foil single body are respectively sleeved on 1 group of M circular truncated cones in a gap or transitional manner; the lower surface of the top foil is welded with the top surfaces of N groups of M round tables; n is more than or equal to 3, and M is more than or equal to 2.

Further, the top foil comprises N top foil units, each top foil unit comprises a fixed section, an abutting section higher than the fixed section, and a turning section which integrally connects the fixed section and the abutting section, and the distance between the lower surface of the fixed section and the lower surface of the abutting section is smaller than the wave height of the wave foil unit; the top surface of each round platform is provided with at least 2 welding spots.

Further, the top foil comprises N top foil monomers, and two adjacent top foil monomers are connected into a whole through a waveform lacing to form a ring shape; the lower surface of the same side edge of each top foil monomer is fixedly connected with the top surfaces of 1 group of M circular truncated cones through laser, microwave or ultrasonic spot welding, and the top surfaces of each circular truncated cone are at least 2 welding spots.

Further, the wave tie includes an inner tie adjacent the inner loop and an outer tie adjacent the outer loop.

Further, the device also comprises N gaskets arranged between the top foil and the corrugated foil single body, each gasket is provided with M through holes, and the gaskets are respectively sleeved on 1 group of M circular tables in a clearance or transitional manner.

Compared with the prior art, the invention has the following beneficial technical effects:

1. the bottom plate and the gasket (optional) in the prior art are omitted, and parts and processing cost are saved.

2. The wave foil does not need to be welded, and deformation of the wave foil caused by welding is avoided.

3. The limiting of the wave foil is realized through the pull ring, the possibility of falling is avoided, and the operation is more reliable.

4. The bottom plate in the prior art is saved, the space is saved, and the miniaturization and the light weight of the gas compressor are facilitated.

5. The structure is simpler and the operation is more reliable.

Drawings

FIG. 1 is a schematic view showing the structure of a bearing housing according to embodiment 1-2 of the present invention.

FIG. 2 is a schematic diagram of the structure of a wave foil unit of the present invention.

FIG. 3 is a schematic structural diagram of the top foil unit in example 1.

Fig. 4 is a schematic structural diagram of the bearing housing in embodiment 1 assembled with the corrugated foil unit and the top foil unit.

Fig. 5 is a schematic structural view of the top foil in example 2.

Fig. 6 is a schematic structural diagram of the bearing housing in example 2 assembled with the corrugated foil unit and the top foil.

Fig. 7 is a schematic view of the structure after cutting away a portion of the top foil.

In the figure, a 100-bearing seat; round bench-102; 1-a bump foil monomer; an extension band-11; pull ring-12; 3-top foil; 31-top foil monomer; 311-fixing section; 312-abutment section; 313-turning segment; 32-wave tie; 321-inner tie; 322-external lacing.

Detailed Description

The present invention will be further described with reference to the drawings by taking the bearing housing 100 as an example.

In embodiment 1, as in the bearing housing 100 of the gas compressor shown in fig. 1, a shaft hole is formed in the center. 6 groups of 2 round tables 102 are formed by upward extension on the end face of the bearing seat 100, and each group of round tables 102 is arranged along the axis circumference of the bearing seat 100; the height of the truncated cone 102 is equal to the thickness of the corrugated foil element 1 described below.

As shown in fig. 2, the wave foil unit 1 has one side extending outwards with the same curvature to form 2 sections of extension bands 11, and the free end of each extension band 11 is connected with one pull ring 12 into a whole.

The 12 pull rings 12 of the 6 corrugated foil units 1 are respectively sleeved on the 12 circular tables 102 in a clearance mode; the 6 wave foil monomers 1 are opposite in head and tail and are equidistantly spaced to form a ring shape.

The top foil unit 31 shown in fig. 3 comprises a fixing section 311, an abutting section 312 higher than the fixing section 311, and a turning section 313 connecting the fixing section 311 and the abutting section 312 into a whole, wherein the distance between the lower surface of the fixing section 311 and the lower surface of the abutting section 312 is smaller than the wave height of the wave foil unit 1.

The lower surfaces of the fixing sections 311 of the 6 top foil units 31 are fixedly connected with the top surfaces of the 12 circular tables 102 through laser spot welding. The top surface of each round platform is provided with at least 2 welding spots. In another preferred embodiment microwave welding or ultrasonic welding may be selected.

After the 6 top foil units 31 are welded and fixed, the turning section 313 and the abutting section 312 of each top foil unit 31 are tilted upwards, and each top foil unit 31 presents a slope shape with one end being low and one end being high.

In order to conveniently explain the structural relationship between the corrugated foil unit 1 and the top foil unit 3 and the bearing block 100, in fig. 4, the right 3 top foil units 3 on the end surface of the bearing block 100 are hidden, and the corrugated foil unit 1 on the right is hidden. The 2 small black spots on the top foil element 3 in the figure are welded spots.

The air bearing of this embodiment is an air thrust bearing, which is respectively installed on a diffuser and a bearing seat, and is installed in a pair of mirror images, when the shaft rotates, the surrounding air is driven to rotate and flow simultaneously, when the air flowing in rotation flows through the annular top foils 3 with high and low intervals, under the action of the adsorption effect of the boundary layer, the thrust force to be separated from each other is generated between the pair of air thrust bearings, the faster the rotation speed of the shaft is, the larger the generated thrust force is correspondingly, the pressure of the air entering the wave-shaped grooves on the lower surface of each wave-foil unit 1 is also, and each wave-foil unit 1 can bear against each top foil unit 31 so as not to be collapsed, which is a dynamic balance process, in this process, the wave-foil unit 1 is deformed in a small scale, and the wave height has a small scale change so as to adapt to the change of the rotation speed of the shaft.

Embodiment 2, as shown in fig. 5-7, is otherwise the same as embodiment 1, except that the top foil 3 is in an annular integral structure, and two adjacent top foil units 31 are connected into a whole through a waveform lacing 32 to form an annular shape; the wavy lacing 32 includes an inner lacing 321 adjacent the inner loop and an outer lacing 322 adjacent the outer loop. The wavy lacing 32 serves to flexibly connect adjacent top foil elements 31.

The same side edge and the lower surface of each top foil unit 31 are fixedly connected with the top surfaces of the 2 circular tables 102 through laser spot welding. The top surface of each round platform is provided with at least 2 welding spots. In another preferred embodiment microwave welding or ultrasonic welding may be selected. After welding, the lower surface of the annular top foil 3 is partially abutted with the non-wave body part of the wave foil single body 1, and is partially abutted with the wave body part of the wave foil single body 1, so that the wave tie 32 is naturally bent and deformed, and the whole annular top foil 3 is in annular sawtooth wave shape with alternating height. Because the wavy lacing 32 has a traction effect on the adjacent top foil units 31, the top surface of the whole top foil is smoother, the uniformity of stress and friction is improved, the abrasion is reduced, and the service life is prolonged.

In fig. 7, the right side of the top foil 3 is half-cut, and the corrugated foil element 1 at the right side of the end surface of the bearing housing 100 is hidden. The small black spots on the top foil 3 in the figure are soldered spots.

In the embodiment 3, on the basis of any one of the embodiments 1-2, 6 gaskets are added, the lower surface of each gasket is fixedly connected with the corrugated foil unit 1 near the free end of the non-waveband 11 through laser spot welding, and the upper surface of each gasket is fixedly connected with the lower surface of the top foil 3 through laser spot welding. The thickness of the spacer can be adjusted as required, and the fluctuation gradient of the single corrugated foil unit 31 can be adjusted by sleeving the spacers with different thicknesses.

The above embodiments are not to be taken as limiting the scope of the invention, and any alternatives or modifications to the embodiments of the invention will be apparent to those skilled in the art and fall within the scope of the invention.

The present invention is not described in detail in the present application, and is well known to those skilled in the art.

Claims

1. The utility model provides an air bearing without bottom plate, includes top foil (3) and N ripples foil monomer (1), its characterized in that: one side of each corrugated foil unit (1) extends outwards with the same curvature to form M sections of extension belts (11), and the free end of each extension belt (11) is connected with one pull ring (12) into a whole; n groups of M circular truncated cones (102) are formed by upward extension on the end face of the diffuser or the bearing seat (100), and each group of circular truncated cones (102) is arranged along the axis circumference of the diffuser or the bearing seat (100); the height of the round table (102) is larger than or equal to the thickness of the corrugated foil single bodies (1), and M pull rings (12) of each corrugated foil single body (1) are respectively sleeved on 1 group of M round tables (102) in a clearance or transitional manner; the lower surface of the top foil (3) is welded with the top surfaces of N groups of M circular tables (102) in each group respectively; n is more than or equal to 3, and M is more than or equal to 2.

2. A bottomless air bearing as set forth in claim 1 wherein: the top foil (3) comprises N top foil units (31), each top foil unit (31) comprises a fixed section (311), an abutting section (312) higher than the fixed section (311), and a turning section (313) which integrally connects the fixed section (311) and the abutting section (312), and the distance between the lower surface of the fixed section (311) and the lower surface of the abutting section (312) is smaller than the wave height of the Yu Bobo unit (1); the lower surface of the fixing section (311) of each top foil unit (31) is fixedly connected with the top surfaces of the M circular tables (102) through laser, microwave or ultrasonic spot welding, and the top surface of each circular table (102) is provided with at least 2 welding spots.

3. A bottomless air bearing as set forth in claim 1 wherein: the top foil (3) comprises N top foil monomers (31), and two adjacent top foil monomers (31) are connected into a whole through a waveform lacing (32) to form a ring shape; the lower surface of the same side edge of each top foil monomer (31) is fixedly connected with the top surfaces of 1 group of M circular tables (102) through laser, microwave or ultrasonic spot welding, and the top surface of each circular table (102) is provided with at least 2 welding spots.

4. A bottomless air bearing as set forth in claim 3 wherein: the wave tie (32) includes an inner tie (321) adjacent the inner loop and an outer tie (322) adjacent the outer loop.

5. A bottomless air bearing as set forth in any one of claims 1-4, wherein: the corrugated foil packaging structure is characterized by further comprising N gaskets arranged between the top foil (3) and the corrugated foil single body (1), M through holes are formed in each gasket, and the gaskets are respectively sleeved on 1 group of M circular tables (102) in a gap or transitional mode.