A radial hydrodynamic air bearing and motor having a double-layer coupled laminated wave foil

Abstract

The present invention relates to a radial hydrodynamic air bearing and a motor having a double-layer coupled laminated wave foil, belonging to the technical field of air bearings. The radial hydrodynamic air bearing includes a bearing housing, a bottom foil, a double-layer wave foil, and a bushing. The double-layer wave foil includes a first wave foil and a second wave foil arranged in a laminated manner, and the second wave foil and the first wave foil are sequentially laminated on the bottom foil; the first wave foil includes a plurality of interconnected first protrusions and second protrusions, and both the first protrusions and the second protrusions protrude in a direction away from the bottom foil; the second wave foil includes a plurality of interconnected third protrusions and fourth protrusions, and both the third protrusions and the fourth protrusions protrude in a direction towards the bottom foil; and, the first protrusions are laminated above the third protrusions, and the second protrusions are laminated above the fourth protrusions. The present invention provides a double-layer coupled laminated wave foil structure in the air bearing, and effectively improves the pressure bearing capacity and stability of the radial hydrodynamic air bearing by optimizing the structure, shape, and layout of the wave foil.

Description

Technical Field

[0001] The present invention relates to a radial dynamic pressure air bearing and a motor having a double-layer coupled laminated wave foil, and belongs to the technical field of air bearings. Background Art

[0002] An air bearing is a sliding bearing that uses gas as a lubricant. Air bearings are divided into three categories: aerostatic bearings, aerodynamic bearings, and squeeze film bearings. Their advantages include high precision, extremely high rotational speed, low friction, and low heat generation. However, due to their working mode, the bearing capacity of an air bearing for a rotating shaft under working conditions is relatively low. In a foil air dynamic pressure bearing, the wave foil part is an important part, which can improve the bearing capacity of the air bearing and resist vibration and shock.

[0003] Taking a radial dynamic pressure air bearing as an example, generally, a radial dynamic pressure air bearing includes a bottom foil and a wave foil. The wave foil and the bottom foil are not closed along the circumferential direction and are of an open structure. One end is called the free end, and the other end is called the fixed end. However, in this traditional foil installation method, the free end is prone to dynamic instability due to uneven air film pressure distribution, and single-layer buffering leads to local stress concentration, restricting the improvement of the bearing capacity. During the operation of the bearing, the air film pressure will cause the foil to deform, and the close contact and friction between the foils will also cause the free end to be easily displaced, thus affecting the pressure bearing capacity and stability of the radial dynamic pressure air bearing.

[0004] Therefore, there is an urgent need for a radial dynamic pressure air bearing with high bearing capacity and high stability. Summary of the Invention

[0005] An object of the present invention is to provide a radial dynamic pressure air bearing having a double-layer coupled laminated wave foil. Through geometric parameter matching and spatial laminated design, multi-stage dissipation and adaptive balanced distribution of air film pressure are realized, effectively improving the pressure bearing capacity and stability of the radial dynamic pressure air bearing.

[0006] Another object of the present invention is to provide a motor.

[0007] The technical solution of the present invention is as follows:

[0008] On the one hand, the present application provides a radial dynamic pressure air bearing having a double-layer coupled laminated wave foil, including a bearing housing, a bottom foil, and a sleeve. The sleeve is sleeved outside the rotating shaft, the bottom foil is disposed between the bearing housing and the sleeve, and a double-layer wave foil is disposed inside the bottom foil. The double-layer wave foil includes a first wave foil and a second wave foil arranged in a laminated manner, and the second wave foil and the first wave foil are sequentially laminated on the bottom foil from the inside to the outside;

[0009] The first wave foil includes a plurality of interconnected first protrusions and second protrusions, and both the first protrusions and the second protrusions protrude in a direction away from the bottom foil;

[0010] The second wave foil includes a plurality of interconnected third protrusions and fourth protrusions, both the third protrusions and the fourth protrusions protrude towards the bottom foil;

[0011] Moreover, the first protrusion is stacked above the third protrusion, and the second protrusion is stacked above the fourth protrusion.

[0012] Preferably according to the present invention, in the double-layer wave foil, one end of the first wave foil and one end of the second wave foil are fixed together and then fixed to the inner side of the bottom foil; the other end of the first wave foil and the other end of the second wave foil are fixed together and are in a free state, not fixed to the bottom foil.

[0013] Preferably according to the present invention, a first connecting portion is provided between the first protrusion and the second protrusion, and the first connecting portion is alternately arranged between the first protrusion and the second protrusion along the circumferential direction of the radially acting hydrodynamic air bearing;

[0014] And / or, a second connecting portion is provided between the third protrusion and the fourth protrusion, and the second connecting portion is alternately arranged between the third protrusion and the fourth protrusion along the circumferential direction of the radially acting hydrodynamic air bearing.

[0015] Preferably according to the present invention, the first protrusion is stacked on the upper part of the third protrusion and the second connecting portions on both sides; the second protrusion and the first connecting portions on both sides are stacked on the upper part of the fourth protrusion.

[0016] Preferably according to the present invention, the first protrusion, the first connecting portion and the second protrusion are all arc-shaped; the chord length of the first protrusion is greater than the chord length of the second protrusion, and the height of the first protrusion is greater than the height of the second protrusion;

[0017] And / or, the third protrusion, the second connecting portion and the fourth protrusion are all arc-shaped; the chord length of the fourth protrusion is greater than the chord length of the third protrusion, and the height of the fourth protrusion is greater than the height of the third protrusion.

[0018] Preferably according to the present invention, the distance from the top of the second protrusion to the bottom foil is greater than the distance from the top of the second connecting portion to the bottom foil;

[0019] And / or, the distance from the top of the third protrusion to the bottom foil is less than the distance from the top of the first connecting portion to the bottom foil.

[0020] Preferably according to the present invention, the structures of the first protrusion and the fourth protrusion are correspondingly the same, the structures of the second protrusion and the third protrusion are correspondingly the same, and the structures of the first connecting portion and the second connecting portion are correspondingly the same.

[0021] Preferably according to the present invention, a plurality of double-layer wave foils are sequentially arranged along the circumferential direction on the inner side of the bottom foil.

[0022] Preferably according to the present invention, a plurality of double-layer wave foils are sequentially arranged along the axial direction on the inner side of the bottom foil.

[0023] On the other hand, the present application provides a motor including the radial foil gas dynamic pressure bearing.

[0024] The beneficial effects of the present invention are as follows:

[0025] In the radial dynamic pressure air bearing structure of the present invention, a double-layer coupled laminated structure wave foil is provided. When the air film squeezes the double-layer coupled laminated structure wave foil structure, the air film pressure is dispersed on the double-layer wave foils, effectively dispersing the air film pressure and avoiding overloading of a single wave foil. A convex structure and a connecting portion are provided on the double-layer coupled laminated structure wave foil, so that each part of the double-layer wave foil forms a gradient buffer for the air film. This gradient can make the air film pressure distribution more reasonable, and avoid local high-pressure areas, enhancing the bearing capacity of the radial dynamic pressure air bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 FIG. is a schematic diagram of the overall structure of the radial dynamic pressure air bearing provided by the present invention.

[0027] Figure 2 FIG. is a schematic diagram of the structure of the bottom foil and the double-layer wave foil in the radial dynamic pressure air bearing provided by the present invention.

[0028] Figure 3 FIG. is a three-dimensional structure diagram of the bottom foil and the double-layer wave foil in the radial dynamic pressure air bearing provided by the present invention.

[0029] Figure 4 FIG. is a schematic diagram of the flattened structure of the bottom foil and the double-layer wave foil in the radial dynamic pressure air bearing provided by the present invention.

[0030] Figure 5 FIG. is a schematic diagram of the flattened structure of the double-layer wave foil in the radial dynamic pressure air bearing provided by the present invention.

[0031] In the figure, 1, bearing housing; 2, bottom foil; 3, first wave foil; 4, second wave foil; 5, double-layer wave foil; 6, bushing; 7, first convex; 8, second convex; 9, first connecting portion; 10, third convex; 11, fourth convex; 12, second connecting portion. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following will disclose several embodiments of the present application, and the technical solutions of the present invention will be clearly and completely described. The accompanying drawings of the specification are used to provide a further understanding of the present invention. The illustrative embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0033] It should be noted that unless the directions separately defined and indicated are otherwise, the directions such as up, down, left, and right involved in this text are based on the up, down, left, and right directions shown in the embodiments of this application. Figure 1 If the specific posture changes, the directional indication will also change accordingly. The "first", "second" and similar terms used in this application do not represent any order, quantity or importance, but are only used to distinguish different components. In addition, in various embodiments of this disclosure, the same or similar reference numerals represent the same or similar components.

[0034] In the present invention, unless otherwise clearly defined and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral body, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0036] Embodiment 1

[0037] This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated wave foil. As shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 , it includes a bearing housing 1, a bottom foil 2 and a bushing 6. The bushing 6 is sleeved outside the rotating shaft, the bottom foil 2 is arranged between the bearing housing 1 and the bushing 6, and a double-layer wave foil 5 is arranged on the inner side of the bottom foil 2. The double-layer wave foil 5 includes a first wave foil 3 and a second wave foil 4 arranged in a laminated manner, and the second wave foil 4 and the first wave foil 3 are sequentially laminated on the bottom foil 2 from inside to outside;

[0038] The first wave foil 3 includes a plurality of interconnected first protrusions 7 and second protrusions 8, and both the first protrusions 7 and the second protrusions 8 protrude in a direction away from the bottom foil 2;

[0039] The second wave foil 4 includes a plurality of interconnected third protrusions 10 and fourth protrusions 11, and both the third protrusions 10 and the fourth protrusions 11 protrude in a direction towards the bottom foil 2;

[0040] Moreover, the first protrusion 7 is laminated above the third protrusion 10, and the second protrusion 8 is laminated above the fourth protrusion 11.

[0041] In the present invention, a double-layer coupled laminated wave foil is provided in a radial hydrodynamic air bearing. The designed protrusions on the double-layer wave foil 5 cooperate with each other (for example, the first protrusion 7 and the fourth protrusion 11 provide initial stiffness to resist low-frequency vibration), thereby improving the load-carrying capacity and stability of the radial hydrodynamic air bearing. The elastic superposition of the double-layer wave foil 5 can better provide gradient buffering, better cope with complex operating conditions, and reduce damage to the bearing and the rotating shaft.

[0042] Embodiment 2

[0043] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled laminated wave foil. The difference from Embodiment 1 is as follows:

[0044] In the double-layer wave foil 5 structure, one end of the first wave foil 3 and one end of the second wave foil 4 are fixed together and then fixed to the inner side of the bottom foil 2; the other end of the first wave foil 3 and the other end of the second wave foil 4 are fixed together and are in a free state, not fixed to the bottom foil 2.

[0045] Such a design can avoid the misalignment of the laminated structure caused by friction between the double-layer wave foils under variable load conditions, better maintain the double-layer coupled laminated wave foil structure, and ensure the load-carrying capacity of the air bearing.

[0046] Embodiment 3

[0047] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled laminated wave foil. The difference from Embodiment 1 is as follows:

[0048] A first connecting portion 9 is provided between the first protrusion 7 and the second protrusion 8, and the first connecting portion 9 is alternately arranged between the first protrusion 7 and the second protrusion 8 along the circumferential direction of the radial hydrodynamic air bearing;

[0049] And / or, a second connecting portion 12 is provided between the third protrusion 10 and the fourth protrusion 11, and the second connecting portion 12 is alternately arranged between the third protrusion 10 and the fourth protrusion 11 along the circumferential direction of the radial hydrodynamic air bearing.

[0050] The first connecting portion 9 and the second connecting portion 12 are alternately arranged along the circumferential direction, which plays a role in increasing the structural stability of the double-layer wave foil 5. It not only makes the structure of the double-layer wave foil 5 more continuous and stable in the circumferential direction, but also can further enhance the hydrodynamic effect by changing the air flow path; further improving the load-carrying capacity of the air bearing.

[0051] Embodiment 4

[0052] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled laminated wave foil. The difference from Embodiment 3 is as follows:

[0053] The first protrusion 7 is stacked on the upper part of the third protrusion 10 and the second connecting parts 12 on both sides; the second protrusion 8 and the first connecting parts 9 on both sides are stacked on the upper part of the fourth protrusion 11.

[0054] On the one hand, this stacking method can evenly transfer the load to each part of the double-layer wave foil 5, avoid local stress concentration, and improve the bearing capacity and reliability of the bearing. On the other hand, through this stacked structure, the double-layer wave foils 5 support each other, increasing the overall stiffness of the double-layer wave foil 5 and ensuring the stability of the hydrodynamic air film.

[0055] Embodiment 5

[0056] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled stacked wave foil. The difference from Embodiment 3 is that:

[0057] The first protrusion 7, the first connecting part 9 and the second protrusion 8 are all arc-shaped; the chord length of the first protrusion 7 is greater than the chord length of the second protrusion 8, and the height of the first protrusion 7 is greater than the height of the second protrusion 8;

[0058] And / or, the third protrusion 10, the second connecting part 12 and the fourth protrusion 11 are all arc-shaped; the chord length of the fourth protrusion 11 is greater than the chord length of the third protrusion 10, and the height of the fourth protrusion 11 is greater than the height of the third protrusion 10.

[0059] The arc-shaped structural design can avoid or reduce the phenomenon of concentrated bearing capacity. When bearing the load, the arc-shaped structure can disperse the bearing capacity more evenly, improving the fatigue life of the double-layer wave foil 5.

[0060] The chord length of the first protrusion 7 is greater than the chord length of the second protrusion 8 and the height is higher, and the chord length of the fourth protrusion 11 is greater than the chord length of the third protrusion 10 and the height is higher. This design forms a gradient bearing structure; the first protrusion 7 and the fourth protrusion 11 provide initial stiffness to resist low-frequency vibration, and as the rotational speed increases, the second protrusion 8 and the third protrusion 10 are sequentially involved in deformation to absorb high-frequency impact, improving the bearing capacity and adaptability of the bearing.

[0061] Embodiment 6

[0062] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled stacked wave foil. The difference from Embodiment 5 is that:

[0063] As Figure 2 and Figure 1 shown, the distance from the top of the second protrusion 8 to the bottom foil 2 is greater than the distance from the top of the second connecting part 12 to the bottom foil 2;

[0064] And / or, the distance from the top of the third protrusion 10 to the bottom foil 2 is less than the distance from the top of the first connecting part 9 to the bottom foil 2.

[0065] Such a design can optimize the load distribution on the double-layer wave foil 5, making it more scientific and reasonable.

[0066] Embodiment 7

[0067] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled laminated wave foil. The difference from Embodiment 2 is as follows:

[0068] The structures of the first protrusion 7 and the fourth protrusion 11 correspond to each other, the structures of the second protrusion 8 and the third protrusion 10 correspond to each other, and the structures of the first connecting portion 9 and the second connecting portion 12 correspond to each other.

[0069] Such a design makes the circumferential lengths of the first wave foil 3 and the second wave foil 4 the same. When bearing the air film pressure, they can evenly share the load, avoiding local stress concentration, thereby improving the overall load-bearing capacity of the double-layer wave foil 5; moreover, it is convenient for design, processing, and installation.

[0070] Embodiment 8

[0071] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled laminated wave foil. The difference from Embodiment 1 is as follows:

[0072] As Figure 3 shown, several double-layer wave foils 5 are sequentially arranged along the circumferential direction on the inner side of the bottom foil 2.

[0073] Embodiment 9

[0074] This embodiment provides a radial hydrodynamic air bearing with a double-layer coupled laminated wave foil. The difference from Embodiment 1 is as follows:

[0075] As Figure 3 shown, several double-layer wave foils 5 are sequentially arranged along the axial direction on the inner side of the bottom foil 2.

[0076] The working principle of the above radial hydrodynamic air bearing is as follows: When the rotating shaft is not floating, the first protrusion 7 in the first wave foil 3 is laminated on the upper parts of the third protrusion 10 and the second connecting portion 12, the second protrusion 8 and the first connecting portion 9 are laminated on the upper part of the fourth protrusion 11, and the fourth protrusion 11 is in contact with the bottom foil 2.

[0077] In the working state, an air film is formed between the bearing sleeve 6 and the rotating shaft. The air film further presses the double-layer wave foil 5. The first wave foil 3 and the second wave foil 4 can bear the air film pressure from two directions. And under the action of the first connecting portion 9 and the second connecting portion 12, the interaction between the various structures of the double-layer wave foil 5 forms a gradient support, enabling the air bearing to bear a greater load.

[0078] Embodiment 10

[0079] A motor, characterized in that it includes the radial dynamic pressure air bearing provided in the above Embodiments 1-9.

[0080] The above description shows and describes the preferred embodiments of the present application. However, as mentioned above, it should be understood that the present application is not limited to the forms disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be within the scope of the concepts herein, through the above teachings or the techniques or knowledge in related fields. And any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present application shall fall within the protection scope of the appended claims of the present application.

Claims

1. A radial hydrodynamic air bearing having a double-layer coupled laminated wave foil, characterized in that, It includes a bearing housing, a bottom foil and a shaft sleeve. The shaft sleeve is sleeved outside the rotating shaft, the bottom foil is arranged between the bearing housing and the shaft sleeve, and a double-layer corrugated foil is arranged on the inner side of the bottom foil. The double-layer corrugated foil includes a first corrugated foil and a second corrugated foil arranged in a stacked manner, and the second corrugated foil and the first corrugated foil are sequentially stacked on the bottom foil from the inside to the outside; The first corrugated foil includes a plurality of first protrusions and second protrusions connected to each other, and both the first protrusions and the second protrusions protrude in a direction away from the bottom foil; The second corrugated foil includes a plurality of third protrusions and fourth protrusions connected to each other, and both the third protrusions and the fourth protrusions protrude in a direction towards the bottom foil; Moreover, the first protrusion is stacked above the third protrusion, and the second protrusion is stacked above the fourth protrusion; A first connecting portion is arranged between the first protrusion and the second protrusion, and the first connecting portion is alternately arranged between the first protrusion and the second protrusion along the circumferential direction of the circumferential direction of the hydrodynamic air bearing; And / or, a second connecting portion is arranged between the third protrusion and the fourth protrusion, and the second connecting portion is alternately arranged between the third protrusion and the fourth protrusion along the circumferential direction of the circumferential direction of the hydrodynamic air bearing; The first protrusion is stacked on the upper part of the third protrusion and the second connecting portions on both sides; the second protrusion and the first connecting portions on both sides are stacked on the upper part of the fourth protrusion.

2. The radial hydrodynamic air bearing with a double-layer coupled laminated wave foil according to claim 1, characterized in that, In the double-layer corrugated foil, one end of the first corrugated foil and one end of the second corrugated foil are fixed together and then fixed to the inner side of the bottom foil; the other end of the first corrugated foil and the other end of the second corrugated foil are fixed together and are in a free state.

3. The radial dynamic pressure air bearing with a double-layer coupled laminated wave foil according to claim 1, characterized in that, The first protrusion, the first connecting portion and the second protrusion are all arc-shaped; the chord length of the first protrusion is greater than the chord length of the second protrusion, and the height of the first protrusion is greater than the height of the second protrusion; And / or, the third protrusion, the second connecting portion and the fourth protrusion are all arc-shaped; the chord length of the fourth protrusion is greater than the chord length of the third protrusion, and the height of the fourth protrusion is greater than the height of the third protrusion.

4. The radial dynamic pressure air bearing with a double-layer coupled laminated wave foil according to claim 3, characterized in that, The distance from the top of the second protrusion to the bottom foil is greater than the distance from the top of the second connecting portion to the bottom foil; And / or, the distance from the top of the third protrusion to the bottom foil is less than the distance from the top of the first connecting portion to the bottom foil.

5. The radial hydrodynamic air bearing with a double-layer coupled laminated wave foil according to claim 2, characterized in that, The structures of the first protrusion and the fourth protrusion are correspondingly the same, the structures of the second protrusion and the third protrusion are correspondingly the same, and the structures of the first connecting portion and the second connecting portion are correspondingly the same.

6. The radial hydrodynamic air bearing with a double-layer coupled laminated wave foil according to claim 1, characterized in that, A plurality of double-layer corrugated foils are sequentially arranged along the circumferential direction on the inner side of the bottom foil.

7. The radial hydrodynamic air bearing with a double-layer coupled laminated wave foil according to claim 1, characterized in that, A plurality of double-layer corrugated foils are sequentially arranged along the axial direction on the inner side of the bottom foil.

8. A motor, characterized in that, It includes the hydrodynamic air bearing according to any one of claims 1-7.

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