Radial gas bearing and electric machine applying same

Abstract

This invention relates to the field of gas bearing technology, specifically to a radial gas bearing and a motor using the same. The radial gas bearing includes a bearing housing, a top foil, and a corrugated foil assembly, the corrugated foil assembly being disposed between the inner wall of the bearing housing and the top foil. The corrugated foil assembly includes a second corrugated foil structure, a first corrugated foil structure, and a third corrugated foil structure arranged sequentially along the axial direction of the bearing housing, all extending circumferentially from the bearing housing. The first corrugated foil structure has two or more first arched foil sheets, each first arched foil sheet having two or more first arched portions arranged sequentially circumferentially. Each first arched foil sheet is sequentially stacked radially from the bearing housing. The height of the first corrugated foil structure is less than the height of the second corrugated foil structure, and the height of the first corrugated foil structure is less than the height of the third corrugated foil structure. According to the technical solution of this invention, it has greater stiffness and a wider load-bearing capacity range, and can reduce end-leakage effects.

Description

Technical Field

[0001] This invention relates to the field of gas bearing technology, and in particular to a radial gas bearing and an electric motor using the same. Background Technology

[0002] Air-bearing radial bearings are a type of air bearing (also known as radial gas bearings). Air bearings are sliding bearings that use gas (usually air, but other gases may also be used) as a lubricant. Air has lower viscosity than oil, is more resistant to high temperatures, and is pollution-free, making it suitable for use in high-speed machinery, instruments, and radioactive devices. However, its load capacity is lower than that of oil. Air bearings are classified into: air hydrodynamic bearings, air hydrostatic bearings, and extrusion film bearings.

[0003] Aerodynamic bearings include radial gas bearings and axial gas bearings. The function of radial gas bearings is to limit the radial movement of high-speed shafts and provide support for shaft buoyancy. The function of axial gas bearings is to limit the axial movement of high-speed shafts and balance unbalanced axial forces from the load end.

[0004] like Figure 1 As shown, patent CN211398261U discloses a radial gas bearing for installation on a motor, comprising a bearing housing 20', a top foil 30', and a corrugated foil assembly. The bearing housing 20' has an inner wall for enclosing a hollow cavity to accommodate a rotating shaft 10'; the top foil 30' is disposed within the hollow cavity; and the corrugated foil assembly is supported between the top foil 30' and the inner wall of the housing. The corrugated foil assembly may include multiple layers of elastic arched foil sheets 40', with adjacent layers of elastic arched foil sheets 40' stacked along the radial portion of the bearing housing 20'.

[0005] The aforementioned corrugated foil assembly, being composed of multiple layers of elastic arched foil sheets 40', possesses high stiffness and load-bearing capacity, enabling it to adapt to various operating conditions ranging from low speed to high-speed heavy loads, and exhibiting a wide range of load-bearing performance. However, due to the uniform axial structural stiffness of the corrugated foil assembly, the axial deformation of the assembly is uniform during the movement of the rotating shaft 10', resulting in a corresponding increase in end leakage effect. This design flaw leads to a decrease in the overall load-bearing performance of the radial gas bearing. Summary of the Invention

[0006] In view of this, the present invention provides a radial gas bearing and a motor using the same, the main technical problem to be solved being: how to reduce the end leakage effect of the radial gas bearing while ensuring its large load capacity range.

[0007] To achieve the above objectives, the present invention mainly provides the following technical solutions:

[0008] In a first aspect, embodiments of the present invention provide a radial gas bearing, which includes a bearing housing, a top foil, and a corrugated foil assembly, wherein the corrugated foil assembly is disposed between the inner wall of the bearing housing and the top foil; the corrugated foil assembly includes a second corrugated foil structure, a first corrugated foil structure, and a third corrugated foil structure arranged sequentially along the axial direction of the bearing housing, wherein the second corrugated foil structure, the first corrugated foil structure, and the third corrugated foil structure all extend along the circumferential direction of the bearing housing;

[0009] The first wave foil structure has two or more first arch foil sheets, each first arch foil sheet having two or more first arched portions arranged sequentially along the circumference, and each first arch foil sheet being stacked sequentially along the radial direction of the bearing housing;

[0010] The height of the first wave foil structure is less than the height of the second wave foil structure, and the height of the first wave foil structure is less than the height of the third wave foil structure.

[0011] In some embodiments, the first arched portions on adjacent first arched foil sheets are inserted and fitted one-to-one.

[0012] In some embodiments, there is a gap between the two interlocking first arched portions on adjacent first arched foil sheets;

[0013] And / or, each of the two adjacent first arched portions of each first arched foil has a connecting segment, and each connecting segment on the adjacent first arched foil is correspondingly contacted.

[0014] In some embodiments, when there is a connecting section between each of the two adjacent arched portions of the first arched foil, the first corrugated foil structure includes a first A arched foil and a first B arched foil located on both sides, and the first arched portion on the first A arched foil arches toward the first B arched foil side.

[0015] The first wave foil structure is in line contact with the first component through the arched portion on the first B arch foil, and in surface contact with the second component through the connecting section on the first A arch foil;

[0016] The first component is a component adjacent to the first wave foil structure, and the first component is located on the side of the first wave foil structure opposite to the first A arch foil sheet; the second component is a component adjacent to the first wave foil structure, and the second component is located on the side of the first wave foil structure opposite to the first B arch foil sheet.

[0017] In some embodiments, the second corrugated foil structure has a second arched foil and a second flat foil, the second arched foil having two or more second arched portions arranged sequentially in the circumferential direction; the second arched foil and the second flat foil are stacked sequentially in the radial direction of the bearing housing.

[0018] In some embodiments, each of the second arched portions is staggered with each of the first arched portions.

[0019] In some embodiments, the third wave foil structure has a third arched foil and a third flat foil, the third arched foil having two or more third arched portions arranged sequentially along the circumference; the third arched foil and the third flat foil are stacked sequentially along the radial direction of the bearing housing.

[0020] In some embodiments, each of the third arched portions is staggered with each of the first arched portions.

[0021] In some embodiments, when the second wave foil structure comprises a second arched foil and a second flat foil stacked sequentially along the radial direction of the bearing housing,

[0022] The second arched foil, a first arched foil, and a third arched foil are arranged sequentially at intervals along the axial direction of the bearing housing, and one end of each of them is connected to the first connecting piece to form a first foil layer. The first foil layer is fixedly connected to the bearing housing through the first connecting piece.

[0023] And / or, the second flat foil, the other first arched foil, and the third flat foil are arranged sequentially at intervals along the axial direction of the bearing housing, and one end of each of them is connected to the second connecting piece to form a second foil layer, which is fixedly connected to the bearing housing through the second connecting piece.

[0024] In some embodiments, the stiffness of the first wave foil structure is greater than that of the second wave foil structure, and the stiffness of the first wave foil structure is greater than that of the third wave foil structure.

[0025] In some embodiments, the radial gas bearing further includes a bottom foil;

[0026] The bottom foil is disposed between the inner wall of the bearing housing and the corrugated foil assembly. The bottom foil extends along the circumferential direction of the bearing housing and has a flat foil structure.

[0027] Secondly, embodiments of the present invention also provide an electric motor that may include any of the radial gas bearings described above.

[0028] By employing the above technical solution, the radial gas bearing of the present invention and the motor using it have at least the following beneficial effects:

[0029] 1. Since the first wave foil structure has two or more stacked first arch foil sheets, compared with the support structure of a single arch foil sheet, the double or multi-layer arch foil structure formed by stacking two or more first arch foil sheets has greater rigidity and stronger load-bearing capacity, and can adapt to multiple working occasions from low speed to high speed heavy load, thereby giving the radial gas bearing of the present invention a larger load-bearing performance range.

[0030] 2. Because the second, first, and third wave foil structures can provide support to different positions of the top foil along the axial direction, and because the height of the first wave foil structure is less than the height of the second wave foil structure, and the height of the third wave foil structure is less than the height of the second wave foil structure, in short, the height of the wave foil at the middle position along the axial direction of the bearing is less than the height of the wave foil on both sides. This can effectively increase the gas film thickness at the middle position, while the gas film thickness at both ends of the axial direction is smaller. The middle area forms a depression that can store high-pressure gas, making it difficult for gas to leak from both sides. This can effectively reduce the end leakage effect of the bearing and improve the stability and load-bearing performance of the bearing.

[0031] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0033] Figure 1 This is a partial structural diagram of a radial gas bearing in the prior art;

[0034] Figure 2 This is a schematic diagram of the structure of a radial gas bearing provided in an embodiment of the present invention;

[0035] Figure 3 yes Figure 2 Enlarged view of point A in the middle;

[0036] Figure 4 This is an assembly diagram of the top foil, the corrugated foil assembly, and the bottom foil.

[0037] Figure 5 This is a partial structural diagram of the first wave foil structure;

[0038] Figure 6 This is a schematic diagram of the first-wave foil structure assembled with the bottom foil and top foil;

[0039] Figure 7 This is a partial structural diagram of the second-wave foil structure;

[0040] Figure 8 This is a partial structural diagram of the third-wave foil structure;

[0041] Figure 9This is a schematic diagram of the structure of the first foil layer;

[0042] Figure 10 yes Figure 9 Side view of the first foil layer;

[0043] Figure 11 This is a schematic diagram of the structure after the first foil layer is unfolded;

[0044] Figure 12 yes Figure 11 A partial side view of the first foil layer after it has been unfolded;

[0045] Figure 13 This is a schematic diagram of the structure of the second foil layer;

[0046] Figure 14 yes Figure 13 Side view of the second foil layer;

[0047] Figure 15 This is a schematic diagram of the structure after the second foil layer is unfolded;

[0048] Figure 16 yes Figure 15 A partial side view of the second foil layer after it has been unfolded.

[0049] Figure 17 This is a schematic diagram of the structure after the top foil or bottom foil is unfolded.

[0050] Reference numerals: 1. Bearing housing; 2. Top foil; 3. Bottom foil; 4. First wave foil structure; 5. Second wave foil structure; 6. Third wave foil structure; 7. Second foil layer; 8. First foil layer; 9. Locking pin; 40. First arched foil; 41. First A arched foil; 42. First B arched foil; 400. First arched portion; 403. Connecting section; 51. Second arched foil; 52. Second flat foil; 501. Second arched portion; 61. Third 62. Arched foil sheet; 601. Third flat foil sheet; 70. Third arched portion; 71. Second connecting piece; 72. First edge portion flat foil; 73. Second center portion corrugated foil; 74. Second connecting portion; 75. Inclined section; 80. First connecting piece; 81. First edge portion corrugated foil; 82. First center portion corrugated foil; 83. Second edge portion corrugated foil; 84. First connecting portion; 10. Corrugated foil assembly; 100. Rotating shaft. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0052] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0053] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0054] like Figures 2 to 4 As shown, an embodiment of the present invention provides a radial gas bearing, which includes a bearing housing 1, a top foil 2, and a corrugated foil assembly 10. The corrugated foil assembly 10 is disposed between the inner wall of the bearing housing 1 and the top foil 2. The radial gas bearing of the present invention may further include a bottom foil 3, which is disposed between the inner wall of the bearing housing 1 and the corrugated foil assembly 10. The bottom foil 3 extends along the circumferential direction of the bearing housing 1 and can be a flat foil structure. The bottom foil 3 can provide additional bearing damping for the bearing as a whole, improving the wear resistance of the bearing. One end of the top foil 2, the corrugated foil assembly 10, and the bottom foil 3 can be fixed to the bearing housing 1 by locking pins 9, and the other end of each is a free end. Furthermore, the free ends of both the top foil 2 and the bottom foil 3 extend beyond the free end of the corrugated foil assembly 10 along the circumferential direction of the bearing housing 1. Fixing one end of each of the three prevents slippage of the bearing foils, while the free ends are easily adjustable to prevent the bearing from seizing.

[0055] The aforementioned corrugated foil assembly 10 includes a second corrugated foil structure 5, a first corrugated foil structure 4, and a third corrugated foil structure 6 arranged sequentially along the axial direction of the bearing housing 1. Among them, Figure 5 A partial structural schematic diagram of a first-wave foil structure is shown. Figure 7 A partial structural diagram of a second-wave foil structure has been presented. Figure 8 A partial structural diagram of a third-wave foil structure is shown. The second-wave foil structure 5, the first-wave foil structure 4, and the third-wave foil structure 6 all extend along the circumference of the bearing housing 1. Each of the three structures has an arched portion. Preferably, the second-wave foil structure 5, the first-wave foil structure 4, and the third-wave foil structure 6 form a cylindrical structure, with one end of each structure fixed to the bearing housing 1, and the other end of each structure being a free end.

[0056] like Figure 5 As shown, the aforementioned first wave foil structure 4 has two or more first arched foil sheets 40, each first arched foil sheet 40 having two or more first arched portions 400 arranged sequentially along the circumference. Each first arched portion 400 arches towards the same side relative to the axis of the bearing housing 1, for example, either towards the axis facing the bearing housing 1 or towards the axis away from the bearing housing 1. Each first arched portion 400 is integrally formed on the first arched foil sheet 40. The first arched portions 400 cooperate to form a wave pattern.

[0057] The aforementioned first arched foil sheets 40 are stacked sequentially along the radial direction of the bearing housing 1. The height H1 of the first wave foil structure 4 is less than the height H2 of the second wave foil structure 5, and the height H1 of the first wave foil structure 4 is less than the height H3 of the third wave foil structure 6.

[0058] It should be noted that: the height H1 of the first wave foil structure 4 refers to the maximum distance between opposite sides of the first wave foil structure 4 along the radial direction of the bearing housing 1; the height H2 of the second wave foil structure 5 refers to the maximum distance between opposite sides of the second wave foil structure 5 along the radial direction of the bearing housing 1; and the height H3 of the third wave foil structure 6 refers to the maximum distance between opposite sides of the third wave foil structure 6 along the radial direction of the bearing housing 1.

[0059] In the above example, since the first wave foil structure 4 has two or more stacked first arch foil sheets 40, compared with the support structure of a single-layer arch foil sheet, the double or multi-layer arch foil structure formed by stacking two or more first arch foil sheets 40 has greater stiffness and stronger load-bearing capacity, and can adapt to multiple working occasions from low speed to high speed heavy load, thereby giving the radial gas bearing of the present invention a larger load-bearing performance range.

[0060] Furthermore, the aforementioned second wave foil structure 5, first wave foil structure 4, and third wave foil structure 6 can provide support for different positions of the top foil 2 along the axial direction. This is because the height H1 of the first wave foil structure 4 is less than the height H2 of the second wave foil structure 5, and the height H1 of the first wave foil structure 4 is less than the height H3 of the third wave foil structure 6. In short, the height of the wave foil at the middle position of the bearing along the axial direction is less than the height of the wave foil on both sides. This can effectively increase the gas film thickness at the middle position, while the gas film thickness at both ends of the axial direction is smaller. The middle area forms a depression that can store high-pressure gas, making it difficult for gas to leak from both sides. This can effectively reduce the end leakage effect of the bearing and improve the stability and load-bearing performance of the bearing.

[0061] Preferred, such as Figure 6 As shown, the first arched portions 400 on the adjacent first arched foil sheets 40 are inserted and matched one by one, which makes the assembly structure more compact.

[0062] In a specific application example, there is a gap D between the two interlocking first arched portions 400 on adjacent first arched foils 40. In this example, when the rotational speed of the shaft 100 is low, the first arched portion 400 on the outer first arched foil 40 deforms first, while the first arched portion 400 on the inner first arched foil 40 does not deform. As the rotational speed of the shaft 100 gradually increases, the deformation of the first arched portion 400 on the outer first arched foil 40 increases. When it deforms to the point where the gap D gradually decreases to 0, the double-layer elastic first arched foil 40 coupling structure provides joint support for the shaft 100, thereby effectively improving the variable load adaptability of the gas radial bearing of the present invention.

[0063] like Figure 5 As shown, each of the aforementioned first arch foils 40 has a connecting section 403 between adjacent first arched portions 400. The connecting sections 403 on adjacent first arch foils 40 are arranged in a one-to-one correspondence to limit the insertion depth of the first arched portion 400, which facilitates the assembly of adjacent first arch foils 40. In addition, the one-to-one correspondence of the connecting sections 403 on adjacent first arch foils 40 can also increase the friction between adjacent first arch foils 40, realize the constraint effect of adjacent first arch foils 40 in the circumferential direction, and improve the damping of the bearing.

[0064] In a specific application example, such as Figure 6As shown, when each of the adjacent arched portions of the first arched foil 40 has a connecting section 403, the aforementioned first wave foil structure 4 includes a first A arched foil 41 and a first B arched foil 42 distributed on both sides. Specifically, the first A arched foil 41 and the first B arched foil 42 are both located on the outermost side of the first wave foil structure 4, with the first A arched foil 41 located on one side of the first wave foil structure 4 and the first B arched foil 42 located on the other side of the first wave foil structure 4. The first arched portion 400 on the first A arched foil 41 arches towards the first B arched foil 42. The first wave foil structure 4 is in line contact with the first component through the first arched portion 400 on the first B arched foil 42, and in surface contact with the second component through the connecting section 403 on the first A arched foil 41. The first component is a component adjacent to the first wave foil structure 4, and the first component is located on the side of the first wave foil structure 4 away from the first A arch foil 41; the second component is a component adjacent to the first wave foil structure 4, and the second component is located on the side of the first wave foil structure 4 away from the first B arch foil 42.

[0065] When the radial gas bearing of the present invention includes a bottom foil 3 disposed between the inner wall of the bearing housing 1 and the corrugated foil assembly 10, the first component described above can be one of the bottom foil 3 and the top foil 2, and the second component can be the other of the bottom foil 3 and the top foil 2.

[0066] In the above example, one side of the first wave foil structure 4 is in line contact with the adjacent first component. Specifically, the top of the first arched portion 400 on the first B arch foil 42 is in line contact with the first component. This reduces the frictional resistance between the first arched portion 400 on the first B arch foil 42 and the first component, which facilitates the elastic deformation of the first arched portion 400 on the first B arch foil 42 when compressed, thus providing strong support for the rotating shaft 100. The other side of the first wave foil structure 4 is in surface contact with the adjacent second component. This increases the frictional resistance between the other side of the first wave foil structure 4 and the adjacent second component, providing stable support for the deformation of the first arched portion 400 on the first wave foil structure 4 and improving the stability of the bearing's load-bearing performance.

[0067] In a specific application example, the aforementioned connecting segment 403 can be an arc-shaped segment, with the centerline of the arc-shaped segment coinciding with the axis of the bearing housing 1. Specifically, the first arched portion 400 can be machined on a flat foil, and then the flat foil can be bent to form the required arc-shaped segment between two adjacent first arched portions 400. This has the advantage of convenient processing and also facilitates the contact between the first wave foil structure 4 and the adjacent second component surface through the arc-shaped segment. The arc-shaped segment can be integrally attached to the surface of the second component, such as the top foil 2 or the bottom foil 3, thus maximizing the contact area. This further provides stable support for the deformation of the first arched portion 400 on the first wave foil structure 4, further improving the stability of the bearing's load-bearing performance.

[0068] In a specific application example, such as Figure 7 As shown, the aforementioned second wave foil structure 5 has a second arched foil 51 and a second flat foil 52. The second arched foil 51 has two or more second arched portions 501 arranged sequentially along the circumference. The second arched foil 51 and the second flat foil 52 are stacked sequentially along the radial direction of the bearing housing 1. The height H2 of the second wave foil structure 5 is the sum of the arch height of the second arched foil 51 and the thickness of the second flat foil 52.

[0069] In the above example, the second arched foil 51 can give the second wave foil structure 5 sufficient stiffness and deformation capacity, enabling the second wave foil structure 5 to have a large load-bearing capacity range. The second flat foil 52 can provide additional bearing damping for the bearing as a whole, while improving the bearing's wear resistance and adaptability.

[0070] The aforementioned second arched portions 501 and first arched portions 400 can be staggered to form a labyrinth seal-like effect, preventing high-pressure gas leakage at the middle position, thereby improving the end leakage effect of the radial gas bearing and further enhancing the bearing performance.

[0071] In a specific application example, such as Figure 8 As shown, the aforementioned third wave foil structure 6 has a third arched foil 61 and a third flat foil 62. The third arched foil 61 has two or more third arched portions 601 arranged sequentially along the circumference. The third arched foil 61 and the third flat foil 62 are stacked sequentially along the radial direction of the bearing housing 1. The height H3 of the third wave foil structure 6 is the sum of the arch height of the third arched foil 61 and the thickness of the third flat foil 62.

[0072] In the above example, the third arched foil 61 can give the third wave foil structure 6 sufficient stiffness and deformation capacity, enabling the third wave foil structure 6 to have a large load-bearing capacity range. The third flat foil 62 can provide additional bearing damping for the bearing as a whole, while improving the bearing's wear resistance and adaptability.

[0073] The aforementioned third arched portions 601 and the first arched portions 400 can be staggered to form a labyrinth seal-like effect, preventing high-pressure gas leakage in the middle position, thereby improving the end leakage effect of the radial gas bearing and further enhancing the bearing performance.

[0074] In a specific application example, such as Figure 9 and Figure 10As shown, the aforementioned second arched foil 51, a first arched foil 40, and a third arched foil 61 are arranged sequentially at intervals along the axial direction of the bearing housing 1, and one end of each of them is connected to the first connecting piece 80 to form a first foil layer 8. The first foil layer 8 is fixedly connected to the bearing housing 1 through the first connecting piece 80. Specifically, one end of each of the second arched foil 51, the first arched foil 40, and the third arched foil 61 can be integrally formed at one end of the first connecting piece 80, and the first foil layer 8 is fixedly connected to the bearing housing 1 through the other end of the first connecting piece 80.

[0075] In the above example, the first connecting piece 80 has the effect of limiting the axial position of the second arched foil 51, the first arched foil 40, and the third arched foil 61.

[0076] like Figure 13 and Figure 14 As shown, the aforementioned second flat foil 52, another first arched foil 40, and third flat foil 62 are arranged sequentially at intervals along the axial direction of the bearing housing 1, and one end of each of them is connected to the second connecting piece 70 to form a second foil layer 7. The second foil layer 7 is fixedly connected to the bearing housing 1 through the second connecting piece 70. Specifically, one end of each of the second flat foil 52, the other first arched foil 40, and the third flat foil 62 can be integrally formed at one end of the second connecting piece 70, and the second foil layer 7 is fixedly connected to the bearing housing 1 through the other end of the second connecting piece 70.

[0077] In the above example, the second connecting piece 70 has the effect of limiting the axial position of the second flat foil 52, the other first arched foil 40, and the third flat foil 62.

[0078] For the radial gas bearing of the present invention, the stiffness of the first wave foil structure 4 is greater than that of the second wave foil structure 5, and the stiffness of the first wave foil structure 4 is greater than that of the third wave foil structure 6. In other words, the stiffness of the middle wave foil structure is greater than that of the two side wave foil structures. This can effectively prevent the bearing edge from being subjected to a large load in the center and causing it to warp and come into contact with the rotating shaft 100, thus preventing the bearing from failing.

[0079] In the above example, the stiffness of the first wave foil structure 4, the second wave foil structure 5, and the third wave foil structure 6 can be tested using existing conventional stiffness testing equipment. Specifically, when the same force F is applied to the first wave foil structure 4, the second wave foil structure 5, and the third wave foil structure 6 along the radial direction of the bearing housing 1, all three structures will deform. At this time, the heights of all three structures will change. The height difference before and after deformation is ΔH1 for the first wave foil structure 4, ΔH2 for the second wave foil structure 5, and ΔH3 for the third wave foil structure 6. The stiffness of the first wave foil structure 4 is greater than that of the second wave foil structure 5, and the stiffness of the first wave foil structure 4 is greater than that of the third wave foil structure 6. Therefore, ΔH1 is less than ΔH2, and ΔH3 is less than ΔH3.

[0080] One embodiment of the present invention also proposes an electric motor that may include any of the radial gas bearings described above. In this example, because the motor includes the aforementioned radial gas bearing, its bearing has a wide load-bearing capacity range, and the end leakage effect of the bearing can be effectively reduced, thereby improving the stability and load-bearing capacity of the bearing.

[0081] The working principle and preferred embodiments of the present invention are described below.

[0082] The present invention relates to the design of a radial gas bearing that can be applied to an electric motor. The radial gas bearing has a corrugated foil assembly 10 located between a top foil 2 and a bottom foil 3, the corrugated foil assembly 10 preferably employing a double-layer foil structure. The double-layer foil consists of a first foil layer 8 and a second foil layer 7.

[0083] Figure 9 A front view of a first foil layer 8 is shown; Figure 10 A side view of a first foil layer 8 is shown. The first foil layer 8 is divided into three parts along the axial direction of the bearing: a second arched foil 51, a first arched foil 40, and a third arched foil 61. One end of each of the three arched foils is connected to a first connecting piece 80. Figure 11 This is a schematic diagram of the structure after the first foil layer 8 is unfolded. Figure 12 This is a partial side view of the first foil layer after it has been unfolded. From Figure 11As can be seen, the first foil layer 8, after being unfolded, has three parts arranged at intervals along its width. After being pressed by a special mold, it forms a first edge corrugated foil 81, a first center corrugated foil 82, and a second edge corrugated foil 83, with a first connecting portion 84 formed at one end of the foil. Then, it is wound by a forming mold and heat-treated to form the aforementioned first foil layer 8. The first center corrugated foil 82 forms the aforementioned first arched foil 40, the first edge corrugated foil 81 forms the aforementioned second arched foil 51, the second edge corrugated foil 83 forms the aforementioned third arched foil 61, and the first connecting portion 84 forms the aforementioned first connecting piece 80. The second arched foil 51 and the third arched foil 61 have the same arch height, pitch, and structural stiffness. The first arched foil 40 differs from the second arched foil 51 and the third arched foil 61 in arch height, structural stiffness, and placement position. However, the first arched foil 40 has the same pitch as the second arched foil 51 and the third arched foil 61, so that the arched part of the first arched foil 40 is staggered with the arched parts of the second arched foil 51 and the third arched foil 61 to form a structure with staggered crests, which improves the end leakage effect of the radial bearing and further improves the bearing performance.

[0084] Figure 13 A front view of a second foil layer 7 is shown; Figure 14 A side view of a second foil layer 7 is shown. The second foil layer 7 is divided into three parts along the axial direction of the bearing: a second flat foil 52, another first arched foil 40, and a third flat foil 62. One end of each of the three parts is connected to a second connecting piece 70. Figure 15 This is a schematic diagram of the structure after the second foil layer 7 is unfolded; Figure 16 This is a partial side view after the second foil layer has been unfolded. From Figure 15 As can be seen, the second foil layer 7, when unfolded, has three parts arranged at intervals along its width. After being pressed by a special mold, it forms a first edge portion flat foil 71, a second center portion corrugated foil 72, and a second edge portion flat foil 73, with a second connecting portion 74 formed at one end of the corrugated foil. Then, after being wound by a forming mold and heat-treated, the aforementioned second foil layer 7 is formed. The second center portion corrugated foil 72 forms the aforementioned first arched foil 40, the first edge portion flat foil 71 forms the aforementioned second flat foil 52, the second edge portion flat foil 73 forms the aforementioned third flat foil 62, and the second connecting portion 74 forms the aforementioned second connecting piece 70. It should be noted here that: Figure 14 As shown, one end of both the second flat foil 52 and the third flat foil 62 is connected to the second connecting piece 70 via an inclined section 75, such that one side of both the second flat foil 52 and the third flat foil 62 is slightly lower than the other first arched foil 40 in the radial direction. Figure 16 As shown, H6 is slightly smaller than H7.

[0085] The top foil 2 and bottom foil 3 mentioned above are both surrounded by metal foil sheets. Figure 17 A schematic diagram of the structure after the top foil or bottom foil is unfolded is shown. The surface of the top foil 2 is coated with a high-temperature resistant lubricating coating, which plays a role in reducing friction and wear during the start-up and shutdown phases of the motor at high speed.

[0086] The inventive point of this invention is that: 1. The corrugated foil assembly 10 can adopt a double-layer foil structure, wherein the double-layer foil can be stacked sequentially along the radial direction of the bearing housing 1, and the double-layer foil is a first foil layer 8 and a second foil layer 7. For example... Figure 9 As shown, the first foil layer 8 is divided into three parts along the radial direction of the bearing: a second flat foil 52, a first arched foil 40, and a third flat foil 62. Figure 13 As shown, the second foil layer 7 is divided into three parts along the radial direction of the bearing: a second arched foil 51, another first arched foil 40, and a third arched foil 61. The height H4 of the first arched foil 40 is less than the height H5 of the second arched foil 51 and the third arched foil 61, so that the gas film thickness is smaller on both sides and larger in the middle, which improves the gas end leakage phenomenon, increases the stiffness and damping of the bearing, and improves the bearing load-bearing performance.

[0087] 2. Both the first foil layer 8 and the second foil layer 7 have a three-segment structure along the axial direction of the bearing housing 1. Specifically, the first foil layer 8 has a second flat foil 52, a first arched foil 40, and a third flat foil 62 arranged sequentially along the axial direction of the bearing housing 1; the second foil layer 7 has a second arched foil 51, another first arched foil 40, and a third arched foil 61 arranged sequentially along the axial direction of the bearing housing 1. The first arched portion 400 on the first arched foil 40 is staggered from the second arched portion 501 on the second arched foil 51 and the third arched portion 601 on the third arched foil 61, and the arch height of the first arched portion 400 on the first arched foil 40 is inconsistent with the arch height of the arched portions on the second arched foil 51 and the third arched foil 61. The first foil layer 8 and the second foil layer 7 are stacked to form a corrugated foil assembly 10. The middle region of the corrugated foil assembly 10 has two layers of arched foil, while the edge regions on both sides have only a single layer of arched foil. This results in the corrugated foil assembly 10 having small support stiffness and large deformation on both sides along the axial direction of the bearing housing 1, and large support stiffness and small deformation in the middle region. This can adjust the axial stiffness of the foil, coordinate the axial deformation of the bearing, prevent the bearing edge from lifting up and contacting the rotating shaft 100, which would lead to bearing failure, and improve the bearing load-bearing performance.

[0088] 3. The radial gas bearing of the present invention has a three-section structure in the axial direction. One end of the radial gas bearing in the axial direction has a structure of one top foil 2 + one second flat foil 52 + one second arched foil 51 + one bottom foil 3. The other end of the radial gas bearing in the axial direction has a structure of one top foil 2 + one third flat foil 62 + one third arched foil 61 + one bottom foil 3. The middle region of the radial gas bearing in the axial direction has a structure of one top foil 2 + two first arched foils 40 + one bottom foil 3. The width D1 of the second flat foil 52 is the same as the width D1 of the second arched foil 51. The width D6 of the third flat foil 62 is the same as the width D3 of the third arched foil 61. The width D2 of the two first arched foils 40 is the same along the axial direction of the bearing housing 1. In short, the radial gas bearing has a structure of one top foil + one flat foil + one arched foil + one bottom foil 3 at both ends in the axial direction, and a structure of one top foil 2 + two arched foils + one bottom foil 3 in the middle region. In this design, the stacking height H1 of the two arched foil layers in the middle region is less than the sum of the heights H2 or H3 of the flat foil layer and the arched foil layer at both ends. Specifically, the thickness of each foil is H0. The height H1 of the first wave foil structure 4 is the sum of the height H4 of the first arched foil 40 and the foil thickness H0. The height H2 of the second wave foil structure 5 is the sum of the height H5 of the second arched foil 51 and the foil thickness H0. The height H3 of the third wave foil structure 6 is the sum of the height H5 of the third arched foil 61 and the foil thickness H0. H4 + H0 is less than H5 + H0. This structure allows a "spindle-shaped" air film to be formed between the rotating shaft 100 and the radial bearing during motor operation; that is, a wider and thicker air film is formed in the middle of the wave foil group than at the edges.

[0089] In terms of the structural stiffness of the corrugated foil assembly 10, the first corrugated foil structure 4 in the middle section is a double-layer composite structure, and its structural stiffness is greater than that of the second corrugated foil structure 5 and the third corrugated foil structure 6 in the edge section. Under high pressure load, the deformation of the first corrugated foil structure 4 is smaller than that of the second corrugated foil structure 5 and the third corrugated foil structure 6. This can effectively prevent the bearing edge from being warped due to the large load on the central part, and from contacting the rotating shaft 100, which could lead to bearing failure.

[0090] The beneficial effects of the radial gas bearing of the present invention are as follows: the stiffness of the radial gas bearing of the present invention varies along the axial direction; specifically, the stiffness at both ends of the axial direction is smaller, while the stiffness in the middle region is larger. This increases the bearing's load-bearing capacity range, increases bearing damping, reduces radial bearing end leakage, improves the bearing stiffness, and enhances the bearing's stability and load-bearing capacity while ensuring the bearing's dynamic adaptability.

[0091] The radial gas bearing of this invention increases bearing damping, making the bearing less prone to wear. It also increases the bearing's load range, improving its load-bearing capacity. Furthermore, it mitigates end leakage, enhances gas film stability, and consequently improves the bearing's vibration resistance, load-bearing capacity, and wear resistance.

[0092] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A radial gas bearing, characterized by, The bearing housing (1), top foil (2), and corrugated foil assembly (10) are included. The corrugated foil assembly (10) is disposed between the inner wall of the bearing housing (1) and the top foil (2). The corrugated foil assembly (10) includes a second corrugated foil structure (5), a first corrugated foil structure (4), and a third corrugated foil structure (6) arranged sequentially along the axial direction of the bearing housing (1). The second corrugated foil structure (5), the first corrugated foil structure (4), and the third corrugated foil structure (6) all extend along the circumferential direction of the bearing housing (1). The first wave foil structure (4) has two or more first arch foils (40), each first arch foil (40) has two or more first arched portions (400) arranged sequentially along the circumference, and each first arch foil (40) is stacked sequentially along the radial direction of the bearing housing (1). Wherein, the height H1 of the first wave foil structure (4) is less than the height H2 of the second wave foil structure (5), and the height H1 of the first wave foil structure (4) is less than the height H3 of the third wave foil structure (6), so that the height of the wave foil at the middle position of the radial gas bearing along the axial direction is less than the height of the wave foil on both sides, so as to increase the gas film thickness at the middle position, while the gas film thickness at both ends of the axial direction is smaller, forming a thicker gas film in the middle of the wave foil assembly (10) than the edge portion.

2. The radial gas bearing as claimed in claim 1, characterized in that, Each of the first arched parts (400) on the adjacent first arch foil (40) is inserted and fitted in a corresponding manner.

3. The radial gas bearing as described in claim 2, characterized in that, There is a gap D between the two interlocking first arched portions (400) on adjacent first arched foil sheets (40); And / or, each of the two adjacent first arched portions (400) of each of the first arched foils (40) has a connecting segment (403), and each connecting segment (403) on the adjacent first arched foils (40) is connected in contact with each other.

4. The radial gas bearing as described in claim 3, characterized in that, The first wave foil structure (4) includes a first A arch foil (41) and a first B arch foil (42) distributed on both sides, and the first arched portion (400) on the first A arch foil (41) arches toward the first B arch foil (42); The first wave foil structure (4) is in line contact with the first component through the first arched portion (400) on the first B arch foil (42), and is in surface contact with the second component through the connecting section (403) on the first A arch foil (41); The first component is a component adjacent to the first wave foil structure (4), and the first component is located on the side of the first wave foil structure (4) away from the first A arch foil (41); the second component is a component adjacent to the first wave foil structure (4), and the second component is located on the side of the first wave foil structure (4) away from the first B arch foil (42).

5. The radial gas bearing as claimed in claim 1, characterized in that, The second wave foil structure (5) has a second arched foil (51) and a second flat foil (52). The second arched foil (51) has two or more second arched portions (501) arranged in sequence along the circumference. The second arched foil (51) and the second flat foil (52) are stacked in sequence along the radial direction of the bearing housing (1).

6. The radial gas bearing as claimed in claim 5, characterized in that, Each of the second arched portions (501) is staggered with each of the first arched portions (400).

7. The radial gas bearing as claimed in any one of claims 1 to 6, characterized in that, The third wave foil structure (6) has a third arched foil (61) and a third flat foil (62). The third arched foil (61) has two or more third arched portions (601) arranged sequentially along the circumference. The third arched foil (61) and the third flat foil (62) are stacked sequentially along the radial direction of the bearing housing (1).

8. The radial gas bearing as claimed in claim 7, characterized in that, Each of the third arched portions (601) is staggered with each of the first arched portions (400).

9. The radial gas bearing as claimed in claim 7, characterized in that, When the second wave foil structure (5) includes a second arched foil (51) and a second flat foil (52) stacked sequentially along the radial direction of the bearing housing (1), The second arched foil (51), a first arched foil (40) and a third arched foil (61) are arranged sequentially at intervals along the axial direction of the bearing housing (1), and one end of each of them is connected to the first connecting piece (80) to form a first foil layer (8). The first foil layer (8) is fixedly connected to the bearing housing (1) through the first connecting piece (80). And / or, the second flat foil (52), another first arched foil (40) and the third flat foil (62) are arranged in sequence along the axial direction of the bearing housing (1), and one end of each of them is connected to the second connecting piece (70) to form a second foil layer (7), and the second foil layer (7) is fixedly connected to the bearing housing (1) through the second connecting piece (70).

10. The radial gas bearing as described in any one of claims 1 to 6, 8, and 9, characterized in that, The stiffness of the first wave foil structure (4) is greater than that of the second wave foil structure (5), and the stiffness of the first wave foil structure (4) is greater than that of the third wave foil structure (6).

11. The radial gas bearing as described in any one of claims 1 to 6, 8, and 9, characterized in that, It also includes a bottom foil (3); the bottom foil (3) is disposed between the inner wall of the bearing housing (1) and the corrugated foil assembly (10), the bottom foil (3) extends along the circumferential direction of the bearing housing (1), and the bottom foil (3) is a flat foil structure; And / or, the surface of the top foil (2) has a high-temperature resistant lubricating coating.

12. An electric motor, characterized in that, Includes the radial gas bearing according to any one of claims 1-11.

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