Air bearing with high bearing capacity

Abstract

The utility model discloses an air bearing with high bearing capacity, and relates to the technical field of foil type dynamic pressure air bearings. Comprising a bearing seat, a bump foil sheet and a flat foil sheet are sequentially arranged on the inner ring of the bearing seat, the bump foil sheet and the flat foil sheet are both coaxially fixed with the bearing seat, and the bearing seat is characterized in that a plurality of drainage grooves are formed in the inner wall of the flat foil sheet in the circumferential direction and are arranged in the axial direction. And a staggered bump foil structure is matched, and the flat foils and the bump foils are fixed in opposite rotating directions. The drainage grooves have a guiding effect on airflow, air film pressure distribution can be improved, an air film is formed more easily in the operation process to support the inner ring, and the bearing capacity is improved through cooperation with the bump foil pieces. Air enters the drainage grooves, air film pressure distribution is more reasonable, and compared with a flat foil without the drainage grooves and an equal-wavelength-wave foil, the bearing pressure is greatly improved. When the bearing is subjected to external load, the non-deformability of the gas film is enhanced. In addition, the two foils are fixed in opposite rotating directions, and dynamic friction in operation is reduced due to the same dynamic deformation trend.

Description

Technical Field

[0001] The utility model relates to the technical field of foil type dynamic pressure air bearings, in particular to an air bearing with high load-bearing capacity. Background Art

[0002] Air bearings, also known as pneumatic bearings and air bearings, are sliding bearings that use gas as a lubricant. Compared with traditional liquid-lubricated bearings and rolling bearings, air bearings are widely used in various industrial fields because of their high speed, low noise, no pollution, high reliability and high durability. The working principle of air bearings is to use the viscosity of gas to increase the pressure in the bearing gap, overcome the gravity of the object and make the object levitate. Traditional air bearings are generally composed of a bearing seat, a corrugated foil, and a flat foil, which are arranged in sequence from the outside to the inside. Since air bearings use air as a lubricant, their load-bearing capacity and stability during operation are their important characteristics.

[0003] In the prior art, in order to improve the load-bearing capacity and stability of the air bearing, the prior art generally achieves this by changing the structure of the bump foil, such as:

[0004] (1) Changing the parameters of two adjacent corrugations in the corrugated foil. For example, the technical solution recorded in the Chinese invention patent with publication number CN113513531A, publication date August 12, 2021, and patent name “Gas thrust bearing, bearing assembly, compressor, air conditioner and automobile”.

[0005] (2) Two corrugated foils of different sizes are arranged, and the two corrugated foils are set inside and outside. For example, the technical solution recorded in the Chinese invention patent with publication number CN118328074A, publication date May 21, 2024, and patent name "A dynamic pressure air radial bearing using a double-layer circumferential variable stiffness corrugated foil".

[0006] (3) Two corrugated foils are provided, and the corrugations of the two corrugated foils are axially staggered. For example, the technical solution recorded in the Chinese invention patent with publication number CN118293146A, publication date July 5, 2024, and patent name “A variable stiffness corrugated foil type air dynamic pressure suspension bearing and its application”.

[0007] In the prior art, there are also a few technical solutions that improve the load-bearing capacity by changing the parameters of the flat foil, such as the technical solution recorded in the Chinese invention patent with publication number CN116498647A, publication date July 28, 2023, and patent name "A top foil of a dynamic pressure gas radial foil bearing based on three groove segments and a dynamic pressure gas radial foil bearing". In this technical solution, a number of grooves are opened on the surface of the flat foil, all of which are opened along the radial direction and evenly arranged along the circumference, so as to make the gas converge to the middle section, maintain the gas pressure balance, and improve the load-bearing capacity of the dynamic pressure radial bearing.

[0008] Based on the above-mentioned prior art, the inventor of the present application hopes to propose a new technical solution on the basis of the prior art to improve the load-bearing capacity of the air bearing. Utility Model Content

[0009] The technical problem to be solved by the utility model is: to overcome the shortcomings of the prior art and provide an air bearing with high load-bearing capacity, by providing a drainage groove on the inner wall of the flat foil to guide the airflow to a certain extent, and to effectively improve the pressure distribution of the air film. During operation, the drainage groove structure makes it easier to form an air film, lift the inner ring, and improve the load-bearing capacity.

[0010] The technical solution adopted by the utility model to solve the technical problem is: the high-load-bearing-capacity air bearing comprises a bearing seat, and a corrugated foil and a flat foil are sequentially arranged on the inner ring of the bearing seat, and the corrugated foil and the flat foil are coaxially fixed with the bearing seat, and is characterized in that: a plurality of drainage grooves are opened on the inner wall of the flat foil, each drainage groove is opened along the circumferential direction of the inner wall of the flat foil, and all the drainage grooves are arranged along the axial direction of the flat foil.

[0011] Preferably, first corrugations and second corrugations of different sizes are arranged on the surface of the corrugated foil, and the first corrugations and the second corrugations are arranged alternately.

[0012] Preferably, an opening is provided on one side of the flat foil, and the flat foil is bent at the opening to form a flat foil clamping angle for clamping with the bearing seat.

[0013] Preferably, an opening is provided on one side of the bump foil, and the bump foil is bent at the opening to form a bump foil corner for clamping with the bearing seat, and the flat foil corner is led out from the side opening of the bump foil.

[0014] Preferably, the angle of the corrugated foil is the same as the angle of the flat foil and has an opposite direction.

[0015] Preferably, the depth of the drainage groove along the radial direction of the flat foil accounts for 40% to 50% of the thickness of the flat foil.

[0016] Preferably, the width of the drainage groove is 1.0~2.0 mm.

[0017] Preferably, the width of the drainage groove is 1.5 mm.

[0018] Preferably, the distance between two adjacent drainage grooves is 6 to 10 mm.

[0019] Preferably, the distance between two adjacent drainage grooves is 8 mm.

[0020] Compared with the prior art, the utility model has the following beneficial effects:

[0021] In the high-load-bearing air bearing of the present application, by providing a drainage groove on the inner wall of the flat foil, the airflow is guided to a certain extent, and the pressure distribution of the air film can be effectively improved. During operation, the drainage groove structure makes it easier to form an air film, which lifts the inner ring and improves the load-bearing capacity. After the air enters the drainage groove, the pressure distribution of the air film will be more reasonable, and it can generate a greater load-bearing pressure than a flat foil without a drainage groove. When the bearing is subjected to external loads, the air film can better resist deformation, thereby improving the load-bearing capacity.

[0022] In the high-load-carrying air bearing of the present application, the corrugations on the surface of the wave foil are designed to be arranged alternately with the first corrugation and the second corrugation. Compared with the traditional air bearing, the corrugations on the surface of the wave foil adopt the same parameter setting. The alternating arrangement type air foil bearing can generate higher gas pressure, and as the speed increases, the load-carrying capacity increases faster, has better load-carrying capacity, and improves the working stability of the bearing. Moreover, the wave foil cooperates with the flat foil to further enhance the load-carrying capacity of the air bearing.

[0023] The fixing method of the flat foil clamping angle and the corrugated foil clamping angle in opposite directions, because the flat foil has a tendency to expand outwards as the rotation speed increases and the gas pressure rises. The corrugated foil has a tendency to stretch due to its own deformation and compression. From the overall point of view, the two are fixed in opposite directions and have the same dynamic movement trend, which can reduce relative movement. Thus, it plays a role in reducing dynamic friction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Axonometric view of a high-capacity air bearing.

[0025] Figure 2 Exploded view of a high-capacity air bearing.

[0026] Figure 3 Front view of a high-load-capacity air bearing.

[0027] Figure 4 for Figure 3 AA section view.

[0028] Figure 5 Axonometric view of a high-load-capacity air bearing foil.

[0029] Figure 6 Front view of the high-load-capacity air bearing foil.

[0030] Figure 7 for Figure 6 Enlarged view of point B in the middle.

[0031] Figure 8 Axonometric view of a flat foil for high load-carrying air bearings.

[0032] Fig. 9 Front view of a high-load-capacity air bearing flat foil.

[0033] Fig.10 for Figure 3 Enlarged view of point A in the middle.

[0034] Among them: 1, bearing seat 2, corrugated foil 3, flat foil 4, drainage groove 5, corrugated foil corner 6, corrugated foil ring body 7, first corrugation 8, second corrugation 9, flat foil ring body 10, flat foil corner. DETAILED DESCRIPTION

[0035] Figures 1 to 10 It is the best embodiment of the utility model, and the following Figures 1 to 10 The utility model is further described.

[0036] like Figures 1 to 3 As shown, a high-load-carrying air bearing includes a bearing seat 1, which is an annular body. A bump foil 2 and a flat foil 3 are sequentially arranged inside the bearing seat 1. The bump foil 2 and the flat foil 3 are both coaxially arranged with the bearing seat 1, and the bump foil 2 and the flat foil 3 are respectively fixed to the inner wall of the bearing seat 1.

[0037] like Figures 5 and 6 As shown, the bump foil 2 includes a bump foil ring body 6, which is an annular plate structure, with corrugations arranged on the surface of the bump foil ring body 6, an opening provided on the surface of the bump foil ring body 6, and a bump foil clamping angle 5 provided at the opening, which is first bent along the radial direction of the bump foil ring body 6 and extends to the outside of the bump foil ring body 6, and then further bent vertically to form an "L" shape. The bump foil 2 and the bearing seat 1 are clamped and fixed by the bump foil clamping angle 5.

[0038] Combination Figure 7 In the present high-load-carrying air bearing, the corrugations arranged on the surface of the corrugated foil ring body 6 include a first corrugation 7 and a second corrugation 8. The curvature (chord length) and radial height of the first corrugation 7 and the second corrugation 8 are different. The first corrugation 7 and the second corrugation 8 are alternately arranged on the surface of the corrugated foil ring body 6.

[0039] In the present high-load-carrying capacity air bearing, the corrugations on the surface of the wave foil 2 are designed to be in the form of alternating first corrugations 7 and second corrugations 8. Compared with the traditional air bearing, the corrugations on the surface of the wave foil 2 are set in the same parameter manner. The alternatingly arranged air foil bearing can generate higher gas pressure, and as the rotation speed increases, the load-bearing capacity increases faster, having better load-bearing capacity and improving the working stability of the bearing.

[0040] like Figures 8 and 9 As shown, the flat foil 3 includes a flat foil ring body 9, which is also an annular plate structure. An opening is provided on the surface of the flat foil ring body 9, and a flat foil clamping angle 10 is provided at the opening. The flat foil clamping angle 10 is first bent along the radial direction of the flat foil ring body 9 and extends to the outside of the flat foil ring body 9, and then further bent vertically to form an "L" shape. The flat foil 3 and the bearing seat 1 are clamped and fixed by the flat foil clamping angle 10.

[0041] Combination Fig.10 Since the flat foil 3 is located in the inner circle of the wave foil 2, the opening of the flat foil 3 corresponds to the opening of the wave foil 2 inside and outside, and the flat foil clamping angle 10 is drawn out from the opening of the wave foil 2, and the flat foil clamping angle 10 is at the same height as the wave foil clamping angle 5 after being drawn out, and the arrangement direction is opposite, and the flat foil clamping angle 10 and the wave foil clamping angle 5 are simultaneously clamped in the corresponding groove of the bearing seat 1. The flat foil clamping angle 10 and the wave foil clamping angle 5 are fixed in opposite directions. When the high-load-bearing air bearing is working, the flat foil 3 has a tendency to expand outward as the speed increases and the gas pressure rises. The wave foil 2 relies on its own deformation and compression to produce an elongation trend. From the overall point of view, the two are fixed in opposite directions, and the dynamic movement trend is the same, which can reduce relative movement. Thereby playing a role in reducing dynamic friction.

[0042] Combination Figure 4 In the present high-load-carrying air bearing, a plurality of drainage grooves 4 are provided on the inner wall of the flat foil 3, each drainage groove 4 is arranged along the circumference of the inner wall of the flat foil 3, and all the drainage grooves 4 are provided in sequence along the axial direction of the flat foil 3. The depth of the drainage groove 4 along the radial direction of the flat foil 3 accounts for 40% to 50% of the thickness of the flat foil 3; the width of the drainage groove 4 is 1.0 to 2.0 mm, preferably 1.5 mm, and the spacing between two adjacent drainage grooves 4 is 6 to 10 mm, preferably 8 mm.

[0043] When the high-load-bearing air bearing is working, the circumferentially arranged drainage grooves 4 play a certain guiding role on the airflow, which can effectively improve the pressure distribution of the air film. During operation, the structure with drainage grooves 4 makes it easier to form an air film, which lifts the inner ring and improves the load-bearing capacity. After the air enters the drainage grooves 4, the pressure distribution of the air film will be more reasonable, and it can generate a greater load-bearing pressure than the flat foil 3 without drainage grooves 4. At the same time, these drainage grooves 4 help to increase the stiffness of the air film. When the bearing is subjected to external loads, the air film can better resist deformation, thereby improving the load-bearing capacity.

[0044] The above is only the preferred embodiment of the utility model, and does not limit the utility model in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the utility model without departing from the technical solution of the utility model still belongs to the protection scope of the technical solution of the utility model.

Claims

1. An air bearing with high load-bearing capacity, comprising a bearing seat (1), wherein a corrugated foil (2) and a flat foil (3) are arranged in sequence on the inner ring of the bearing seat (1), wherein the corrugated foil (2) and the flat foil (3) are coaxially fixed to the bearing seat (1), and characterized in that: A plurality of drainage grooves (4) are provided on the inner wall of the flat foil (3), each drainage groove (4) is provided along the circumference of the inner wall of the flat foil (3), and all the drainage grooves (4) are arranged along the axial direction of the flat foil (3).

2. The high load-bearing capacity air bearing according to claim 1, characterized in that: A first corrugation (7) and a second corrugation (8) of different sizes are arranged on the surface of the corrugated foil (2), and the first corrugation (7) and the second corrugation (8) are arranged alternately.

3. The high load-bearing capacity air bearing according to claim 1, characterized in that: An opening is provided on one side of the flat foil (3), and is bent at the opening to form a flat foil clamping angle (10) for clamping with the bearing seat (1).

4. The high load-bearing capacity air bearing according to claim 3, characterized in that: An opening is provided on one side of the bump foil (2), and a bump foil clamping angle (5) is formed by bending at the opening for clamping with the bearing seat (1), and a flat foil clamping angle (10) is led out from the side opening of the bump foil (2).

5. The high load-bearing capacity air bearing according to claim 3, characterized in that: The corrugated foil clamping angle (5) and the flat foil clamping angle (10) are at the same height and in opposite directions.

6. The high load-bearing capacity air bearing according to claim 1, characterized in that: The depth of the drainage groove (4) along the radial direction of the flat foil (3) accounts for 40% to 50% of the thickness of the flat foil (3).

7. The high load-bearing capacity air bearing according to claim 1, characterized in that: The width of the drainage groove (4) is 1.0-2.0 mm.

8. The high load-bearing capacity air bearing according to claim 7, characterized in that: The width of the drainage groove (4) is 1.5 mm.

9. The high load-bearing air bearing according to claim 1, characterized in that: The distance between two adjacent drainage grooves (4) is 6 to 10 mm.

10. The high load-bearing air bearing according to claim 9, characterized in that: The distance between two adjacent drainage grooves (4) is 8 mm.

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