CN114909319A

CN114909319A - Rotating shaft assembly, rotor assembly and compressor

Info

Publication number: CN114909319A
Application number: CN202210549816.4A
Authority: CN
Inventors: 陈彬; 范伟诚; 贾金信; 苏久展; 闫瑾; 陈振
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2022-05-20
Filing date: 2022-05-20
Publication date: 2022-08-16

Abstract

The application provides a pivot subassembly, rotor subassembly and compressor. The rotating shaft assembly comprises a gas dynamic pressure bearing structure and a rotating shaft, wherein the gas dynamic pressure bearing structure comprises a flat foil, a corrugated foil and a bearing seat, and the corrugated foil is arranged between the flat foil and the bearing seat; the rotating shaft penetrates through the flat foil; the pivot include with the shaft part of plain foil contact, be equipped with the recess on the periphery wall at shaft part middle part, the groove depth of recess is at least including first degree of depth and second degree of depth value. This application is through opening the recess in the regional periphery that pivot and gaseous dynamic pressure bearing contacted, when the groove depth of recess contains different depth values, increases wedge effect under the pump suction effect, has increased the gas film thickness of bearing middle zone, reduces the lubricated gas film end of high pressure and lets out the problem, like this need not to improve under the plain foil condition of gaseous dynamic pressure bearing, can obviously improve the bearing capacity of gaseous dynamic pressure bearing.

Description

Rotating shaft assembly, rotor assembly and compressor

Technical Field

The application belongs to the technical field of compressors, and particularly relates to a rotating shaft assembly, a rotor assembly and a compressor.

Background

The gas dynamic pressure bearing structure utilizes the wedge effect, sucks gas into a wedge-shaped area under the condition of high rotating speed, and high-pressure gas is accumulated on the surface of the bearing to provide gas film pressure to support the rotor. The common gas dynamic pressure radial bearing structure comprises a flat foil, a wave foil and a bearing seat, wherein the wave foil is arranged between the bearing seat and the flat foil, and the flat foil is provided with a convex edge which is clamped in a groove of the bearing seat. When the rotor rotates at a high speed, air film pressure is formed between the rotor and the flat foil, and the flat foil and the wave foil generate elastic deformation, so that the air film gap is increased, and rigidity and bearing capacity are provided for the bearing.

The gas dynamic pressure bearing structure has the advantages of high precision, no pollution, high speed, simple structure and the like, and is widely applied at home and abroad, such as oil-free turbines of aircraft engines, low-temperature expanders, air cycle machines of airplanes and other high-speed rotating machines. However, the surface of the existing flat foil is of a planar structure, and the gas films are uniformly distributed in the axial direction, so that the problem that the bearing capacity of the aerodynamic bearing is small due to the fact that the distance between the pressure of the gas film generated in the middle part and the pressure difference of the gas films generated at two ends is small in the bearing operation process occurs.

The main mode of improving the gas film bearing capacity in the prior art is to improve the gas film rigidity of the radial bearing foil and improve the bearing capacity, the gas film thickness of the middle area of the bearing is increased and the gas film thickness of the two ends of the bearing is reduced by changing the thickness of the flat foil along the axial direction, so that the end leakage of lubricating gas at the two ends of the bearing is reduced, the pressure of the lubricating gas is improved, and the bearing capacity is improved.

Disclosure of Invention

Therefore, the application provides a pivot subassembly, rotor subassembly and compressor, can solve among the prior art for overcoming the little and difficult problem of processing that brings of flat foil of improvement of gas dynamic pressure bearing capacity.

In order to solve the above problem, the present application provides a rotary shaft assembly including:

the bearing comprises a gas dynamic pressure bearing structure and a rotating shaft, wherein the gas dynamic pressure bearing structure comprises a flat foil, a wave foil and a bearing seat, and the wave foil is arranged between the flat foil and the bearing seat; the rotating shaft penetrates through the flat foil;

the pivot include with the shaft part of plain foil contact, be equipped with the recess on the periphery wall at shaft part middle part, the groove depth of recess is at least including first degree of depth and second degree of depth value.

Optionally, the groove includes an arc-shaped groove, and a width direction of the arc-shaped groove is in an axial direction of the rotating shaft.

Optionally, the width of the arc-shaped groove is 1/2-3/4 of the axial length of the shaft section.

Optionally, the depth of the arc-shaped groove is 0.15-0.2 mm.

Optionally, the extending direction of the arc-shaped groove is the circumferential direction of the shaft section, the arc-shaped groove integrally forms an annular shape, and the annular shape coincides with the axis of the shaft section.

Optionally, both sides of the arc-shaped groove and both ends of the shaft section are in arc transition arrangement.

Optionally, the groove comprises an annular groove arranged along the periphery of the shaft section and a herringbone groove arranged at the bottom of the annular groove; a plurality of herringbone grooves are uniformly distributed along the circumferential direction of the annular groove; the herringbone groove comprises two inclined grooves, wherein the two inclined grooves are formed by intersecting the same end, extend along the circumferential direction of the annular groove and are obliquely arranged relative to the axial direction of the rotating shaft.

Optionally, the groove depth of the intersection end of the inclined groove is larger than that of the other end.

Optionally, the width of the annular groove is 1/2-3/4 of the axial length of the shaft section, and the groove depth is 0.05-0.1 mm.

Optionally, 20-30 herringbone grooves are arranged; and/or the included angle of the two inclined grooves is 130-140 degrees; and/or the width of the herringbone groove at the intersection is 1.5-2.0 mm, and the depth is 0.015-0.02 mm.

According to another aspect of the present application, there is provided a rotor assembly including the rotary shaft assembly as described above.

According to still another aspect of the present application, there is provided a compressor including the rotary shaft assembly as described above or the rotor assembly as described above.

The application provides a pivot subassembly includes: the bearing comprises a gas dynamic pressure bearing structure and a rotating shaft, wherein the gas dynamic pressure bearing structure comprises a flat foil, a wave foil and a bearing seat, and the wave foil is arranged between the flat foil and the bearing seat; the rotating shaft penetrates through the flat foil; the pivot include with the shaft part of plain foil contact, be equipped with the recess on the periphery wall at shaft part middle part, the groove depth of recess is at least including first degree of depth and second degree of depth value.

This application is through opening the recess in the regional periphery that pivot and aerodynamic bearing contacted, when the groove depth of recess contains different depth values, increases wedge effect under the pump suction effect, has increased the gas film thickness of bearing middle zone, reduces the lubricated gas film end of high pressure and lets out the problem, like this under the plain foil condition that need not to improve aerodynamic bearing, can obviously improve aerodynamic bearing's bearing capacity.

Drawings

FIG. 1 is a schematic structural diagram of a spindle assembly according to an embodiment of the present disclosure;

FIG. 2 is a schematic view of a partial structure of a rotating shaft according to an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of a bearing seat according to an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a bump foil according to an embodiment of the present application;

FIG. 5 is a schematic view of a flat foil according to an embodiment of the present application;

fig. 6 is another schematic structural diagram of the rotating shaft according to the embodiment of the present application.

The reference numerals are represented as:

1. a rotating shaft; 11. an arc-shaped slot; 12. an annular groove; 13. a herringbone groove; 2. a flat foil; 21. a flat foil opening; 22. a flat foil ledge; 3. a bump foil; 31. a bump foil opening; 32. a bump foil convex edge; 33. an arch portion; 34. flattening the top; 4. a bearing seat; 41. a through groove; 5. a wedge-shaped region.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail and completely with reference to the following specific embodiments of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. 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 application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be implemented in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Referring to fig. 1 to 6 in combination, according to an embodiment of the present application, a rotary shaft assembly includes:

the bearing comprises a gas dynamic pressure bearing structure and a rotating shaft 1, wherein the gas dynamic pressure bearing structure comprises a flat foil 2, a wave foil 3 and a bearing seat 4, and the wave foil 3 is arranged between the flat foil 2 and the bearing seat 4; the rotating shaft 1 penetrates through the flat foil 2;

the pivot 1 include with the shaft part of 2 contacts of plain foil, be equipped with the recess on the periphery wall at shaft part middle part, the groove depth of recess is at least including first degree of depth and second degree of depth value.

This application is through opening the recess in the regional periphery that pivot 1 and aerodynamic bearing contacted, when the groove depth of recess contains different depth values, increases wedge region 5 effects under the pump suction effect, has increased the gas film thickness of bearing middle zone, reduces the lubricated gas film end of high pressure and lets out the problem, like this under the flat 2 circumstances of paper tinsel that need not to improve aerodynamic bearing, can obviously improve aerodynamic bearing's bearing capacity.

The gradient groove is formed in the middle section of the area, in contact with the gas dynamic pressure bearing, of the rotating shaft 1, the thickness of a gas film in the area is increased, the end leakage of a high-pressure gas film is reduced, and therefore the bearing capacity and stability of the gas dynamic pressure radial foil bearing are improved.

In some embodiments, the groove comprises an arc-shaped slot 11, and the width direction of the arc-shaped slot 11 is the axial direction of the rotating shaft 1.

An arc-shaped groove 11 is formed in the peripheral surface of the rotating shaft 1, and the width direction of the arc-shaped groove 11 is the axial direction of the rotating shaft 1, which shows that the extending direction of the arc-shaped groove 11 is the circumferential direction of the rotating shaft 1; at the moment, a wedge-shaped area 5 is formed between the rotating shaft 1 and the flat foil 2; when the rotating shaft 1 rotates at a high speed, high-speed relative motion can occur between the surface of the rotating shaft 1 and the inner surface of the flat foil 2, gas in the environment is brought into the wedge-shaped gap due to the viscous action, and a high-pressure gas film is formed by utilizing the dynamic pressure effect so as to support the rotating shaft 1.

In some embodiments, the width of the arcuate slot 11 is 1/2-3/4 of the axial length of the shaft segment. Preferably, the depth of the arc-shaped groove 11 is 0.15-0.2 mm. Preferably, the extending direction of the arc-shaped groove 11 is the circumferential direction of the shaft section, and the arc-shaped groove 11 integrally forms an annular shape, and the annular shape coincides with the axis of the shaft section. Preferably, two sides of the arc-shaped groove 11 and two ends of the shaft section are in arc transition arrangement.

The arc-shaped groove 11 on the rotating shaft 1 is arranged in the middle section of a contact area between the rotating shaft 1 and the flat foil 2, the width of the arc-shaped groove 11 approximately accounts for 1/2-3/4 of the width of the contact area, the groove depth of the arc-shaped groove 11 is gradually increased from two sides to the middle, the groove depth is deepest to 0.15-0.2 mm, the arc-shaped groove 11 is circumferentially distributed in the whole circumference, and the groove starting position is subjected to fillet treatment.

The whole rotating shaft assembly can be regarded as a series supporting structure consisting of the wave foil 3 with self-adaptive elasticity, the flat foil 2 and the dynamic pressure air film provided by the arc-shaped grooves 11. When the rotating speed is increased to a certain value, the arc-shaped groove 11 of the rotating shaft 1 enables a wedge-shaped high-pressure air film to be formed between the rotating shaft 1 and the flat foil 2, so that the rotating shaft 1 is in a gas suspension state, and the rotating shaft 1 is supported to run basically without friction.

The arc-shaped groove 11 with the variable groove depth increases the wedge effect under the condition of pumping effect, reduces the end leakage of high-pressure gas, and further improves the bearing capacity of the bearing.

In some embodiments, the grooves include an annular groove 12 disposed along the outer periphery of the shaft segment, and a chevron groove 13 disposed at the bottom of the annular groove 12; a plurality of herringbone grooves 13 are uniformly distributed along the extending direction of the annular groove 12; the herringbone groove 13 comprises two inclined grooves with the same ends meeting together, the two inclined grooves extend along the extending direction of the annular groove 12 and are obliquely arranged relative to the axial direction of the rotating shaft 1.

The groove can also be set as a combined structure of an annular groove 12 and a herringbone groove 13, the annular groove 12 is firstly opened in the middle section of the outer peripheral surface of the rotating shaft 1 which is contacted with the flat foil 2, and the herringbone groove 13 is arranged on the bottom surface of the annular groove 12 to form a gradient groove structure, so that the thickness of the bearing gas film is changed by integrally forming a wedge-shaped structure.

In some embodiments, the converging end of the diagonal slot has a greater slot depth than the other end.

Preferably, the groove depth of the herringbone groove 13 is set to a structure which is gradually deepened from two sides to the middle, so that the wedge-shaped area 5 is more obvious, and the bearing capacity is improved.

In some embodiments, the annular groove 12 has a width of 1/2-3/4 of the axial length of the shaft segment and a groove depth of 0.05-0.1 mm. Preferably, 20-30 herringbone grooves 13 are arranged; and/or the included angle of the two inclined grooves is 130-140 degrees; and/or the width of the herringbone groove 13 at the intersection is 1.5-2.0 mm, and the depth is 0.015-0.02 mm.

The annular groove 12 of the rotating shaft 1 is arranged in the contact area of the rotating shaft 1 and the flat foil 2, the width of the annular groove 12 is 1/2-3/4 of the width of the contact area, and the depth of the annular groove 12 is 0.05-0.1 mm. 20-30 herringbone grooves 13 are distributed in the annular groove 12 in the circumferential direction, the herringbone grooves 13 are in a splayed shape, and the left groove and the right groove of the herringbone grooves 13 are distributed at equal intervals. The included angle of the herringbone groove 13 is 130-140 degrees, the width of the groove on the top surface of the herringbone groove 13 is 1.5-2.0 mm, the groove depth is 0.015-0.02 mm, and the groove depth is gradually deepened from bosses at two ends to the top point. The herringbone groove 13 with the variable groove depth increases a wedge effect under the pump pressure effect of the annular groove 12, reduces the end leakage of a high-pressure gas, and further improves the bearing capacity of the bearing.

For the gas dynamic pressure bearing structure, the flat foil 2 and the wave foil 3 are both prepared by adopting high-temperature-resistant alloy foils, and in the working state of the gas dynamic pressure bearing, the flat foil 2 sucks high-speed gas due to a wedge-shaped structure, and a high-pressure lubricating gas film is formed at the flat top 34 of the flat foil 2 to provide bearing capacity for the rotating shaft 1.

The whole flat foil 2 is of an annular structure with a flat foil opening 21, and a flat foil convex edge 22 is arranged on one side of the flat foil opening 21; the left side surface of the flat foil ledge 22 abuts the left side inner surface of the through groove 41 on the bearing housing 4, and the right side surface of the through groove 41 abuts the left side surface of the bump 32 to fix the circumferential displacement of the flat foil 2. The outer surface of the flat foil 2 is tangent to the arched portion 33 of the bump foil 3, and its end should completely cover the arched end of the bump foil 3. The inner surface of the flat foil 2 is a main bearing area, and when the rotating shaft 1 rotates at a high speed, a high-pressure lubricating gas film between the flat foil 2 and the rotating shaft 1 provides bearing capacity for the gas dynamic pressure bearing.

The corrugated foil 3 is also of an annular structure with corrugated foil openings 31, and is composed of a flat top portion 34, an arched portion 33, a corrugated foil flange 32 and the corrugated foil openings 31. The flat top 34 is in abutment with the inner surface of the bearing seat 4 and the apex of the arch 33 is tangential to the outer surface of the flat foil 2. The bump edge 32 is disposed between the right side surface of the flat foil edge 22 and the right side inner surface of the through groove 41 of the bearing seat 4, and is attached to the right side inner surface of the through groove 41 to fix the circumferential movement of the bump foil 3. The distance between the vertexes of the adjacent arches 33 of the bump foil 3 is between 3 and 5mm, and the number of the arches 33 is between 25 and 30. When the rotating shaft 1 rotates, under the action of friction torque, the wave foil 3 is deformed from the free end to the fixed end by the pressure transmitted by the flat foil 2, and finally a wedge-shaped area 5 is formed between the rotating shaft 1 and the flat foil 2.

The bearing seat 4 is integrally of an annular structure, a radial bearing is fixedly installed on the inner surface of the bearing seat, an axially through groove 41 is formed in the upper portion of the inner surface of the bearing seat, the through groove 41 is narrow in width and can be just embedded into the flat foil convex edge 22 and the wave foil convex edge 32, and therefore the flat foil 2 and the wave foil 3 are guaranteed against circumferential displacement.

According to still another aspect of the present application, there is provided a compressor including the rotating shaft assembly as described above or the rotor assembly as described above.

It will be readily appreciated by those skilled in the art that the above embodiments may be freely combined, superimposed without conflict.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application. The foregoing is only a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, many modifications and variations can be made without departing from the technical principle of the present application, and these modifications and variations should also be regarded as the protection scope of the present application.

Claims

1. A spindle assembly, comprising:

the bearing comprises a gas dynamic pressure bearing structure and a rotating shaft (1), wherein the gas dynamic pressure bearing structure comprises a flat foil (2), a corrugated foil (3) and a bearing seat (4), and the corrugated foil (3) is arranged between the flat foil (2) and the bearing seat (4); the rotating shaft (1) is arranged in the flat foil (2) in a penetrating way;

the pivot (1) include with the shaft part of plain foil (2) contact, be equipped with the recess on the periphery wall at shaft part middle part, the groove depth of recess is at least including first degree of depth and second degree of depth value.

2. A spindle assembly according to claim 1, characterized in that the recess comprises an arc-shaped slot (11), the width direction of the arc-shaped slot (11) being axial to the spindle (1).

3. A spindle assembly according to claim 2, characterised in that the width of the arcuate slot (11) is 1/2-3/4 of the axial length of the shaft section.

4. A spindle assembly according to claim 3, characterized in that the depth of the arc-shaped slot (11) is 0.15-0.2 mm.

5. A rotary shaft assembly according to claim 4, characterized in that the arc-shaped groove (11) extends in the circumferential direction of the shaft section, and the arc-shaped groove (11) is integrally formed into a ring shape which is coincident with the axis of the shaft section.

6. A rotary shaft assembly according to any one of claims 2-5, characterized in that the two sides of the arc-shaped groove (11) and the two ends of the shaft section are in arc transition arrangement.

7. A rotary shaft assembly as defined in claim 1, wherein the recess comprises an annular groove (12) provided along the outer periphery of the shaft section, and a herringbone groove (13) provided at the bottom of the annular groove (12); a plurality of herringbone grooves (13) are uniformly distributed along the circumferential direction of the annular groove (12); the herringbone groove (13) comprises two inclined grooves with the same ends meeting together, the two inclined grooves extend along the circumferential direction of the annular groove (12) and are obliquely arranged relative to the axial direction of the rotating shaft (1).

8. The pivot assembly of claim 7 wherein the converging end of the angled slot has a greater slot depth than the other end.

9. A spindle assembly according to claim 8, characterised in that the annular groove (12) has a width of 1/2-3/4 of the axial length of the shaft section and a groove depth of 0.05-0.1 mm.

10. A spindle assembly according to any one of claims 7-9, characterized in that there are 20-30 herringbone grooves (13); and/or the included angle of the two chutes is 130-140 degrees; and/or the width of the herringbone groove (13) at the intersection is 1.5-2.0 mm, and the depth is 0.015-0.02 mm.

11. A rotor assembly comprising a rotor assembly as claimed in any one of claims 1 to 10.

12. A compressor comprising a rotary shaft assembly as claimed in any one of claims 1 to 10 or a rotor assembly as claimed in claim 11.