Radial dynamic pressure air bearing with double-layer coupling laminated bump foil and motor

Abstract

The invention relates to a radial dynamic pressure air bearing with double-layer coupling laminated bump foils and a motor, and belongs to the technical field of air bearings. The radial dynamic pressure air bearing comprises a bearing seat, a bottom foil, a double-layer bump foil and a shaft sleeve, the double-layer bump foil comprises a first bump foil and a second bump foil which are arranged in a stacked mode, and the second bump foil and the first bump foil are sequentially arranged on the bottom foil in a stacked mode; the first bump foil comprises a plurality of first bulges and second bulges which are connected with each other, and the first bulges and the second bulges are bulged in the direction deviating from the bottom foil; the second bump foil comprises a plurality of third bulges and fourth bulges which are connected with each other, and the third bulges and the fourth bulges are bulged towards the bottom foil; in addition, the first protrusion is stacked above the third protrusion, and the second protrusion is stacked above the fourth protrusion. According to the radial dynamic pressure air bearing, the double-layer coupling laminated bump foil structure is arranged in the air bearing, and the pressure bearing capacity and stability of the radial dynamic pressure air bearing are effectively improved by optimizing the structure, the shape and the layout of the bump foil.

Description

Technical Field

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

[0002] Air bearings are sliding bearings that use gas as a lubricant. Air bearings are divided into three categories: air static pressure bearings, air dynamic pressure bearings, and squeeze film bearings. Their advantages are high precision, high speed limit, low friction, and low heat generation. However, due to their working method, the air bearing has a low load-bearing capacity on the rotating shaft under working conditions. The foil part is an important part of the foil air dynamic pressure bearing, which improves the load-bearing capacity of the air bearing and resists vibration and impact.

[0003] Taking radial dynamic pressure air bearings as an example, generally speaking, radial dynamic pressure air bearings include a bottom foil and a wave foil. The wave foil and the bottom foil are not closed along the circumferential direction and are open structures, one end of which is called the free end and the other end is called the fixed end. However, this traditional foil installation method is prone to dynamic instability at the free end due to uneven distribution of air film pressure, and the single-layer buffer causes local stress concentration, which restricts the improvement of load-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 misaligned, thereby 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 load-bearing capacity and high stability. Summary of the invention

[0005] One object of the present invention is to provide a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which realizes multi-stage dissipation and adaptive balanced distribution of air film pressure through geometric parameter matching and spatial lamination design, thereby 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: On the one hand, the present application provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, comprising a bearing seat, a bottom foil and a sleeve, wherein the sleeve is sleeved on the outside of a rotating shaft, the bottom foil is arranged between the bearing seat and the sleeve, a double-layer corrugated foil is arranged on the inner side of the bottom foil, the double-layer corrugated foil comprises a first corrugated foil and a second corrugated foil which are laminated, and the second corrugated foil and the first corrugated foil are laminated on the bottom foil in sequence from the inside to the outside; The first corrugated foil comprises a plurality of first protrusions and second protrusions connected to each other, wherein the first protrusions and the second protrusions are protruded in a direction away from the bottom foil; The second corrugated foil comprises a plurality of third protrusions and fourth protrusions connected to each other, wherein the third protrusions and the fourth protrusions both protrude toward the bottom foil; Furthermore, the first protrusion is stacked on the third protrusion, and the second protrusion is stacked on the fourth protrusion.

[0008] Preferably according to the present invention, 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 and are not fixed to the bottom foil.

[0009] 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 provided between the first protrusion and the second protrusion along the circumferential direction of the radial dynamic pressure air bearing; And / or, a second connection portion is disposed between the third protrusion and the fourth protrusion, and the second connection portion is alternately disposed between the third protrusion and the fourth protrusion along the circumferential direction of the radial dynamic pressure air bearing.

[0010] Preferably according to the present invention, the first protrusion is stacked on the third protrusion and the second connecting parts on both sides; the second protrusion and the first connecting parts on both sides are stacked on the fourth protrusion.

[0011] 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; 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.

[0012] According to the present invention, preferably, the distance between the top of the second protrusion and the bottom foil is greater than the distance between the top of the second connecting portion and the bottom foil; And / or, the distance between the top of the third protrusion and the bottom foil is smaller than the distance between the top of the first connecting portion and the bottom foil.

[0013] Preferably according to the present invention, the structures of the first protrusion and the fourth protrusion are identical, the structures of the second protrusion and the third protrusion are identical, and the structures of the first connecting portion and the second connecting portion are identical.

[0014] Preferably according to the present invention, a plurality of double-layer corrugated foils are sequentially arranged on the inner side of the bottom foil along the circumferential direction.

[0015] Preferably according to the present invention, a plurality of double-layer corrugated foils are arranged in sequence along the axial direction on the inner side of the bottom foil.

[0016] On the other hand, the present application provides a motor, comprising the radial foil gas dynamic pressure bearing.

[0017] The beneficial effects of the present invention are: The present invention sets a double-layer coupled laminated structure corrugated foil in the radial dynamic pressure air bearing structure. When the air film squeezes the double-layer coupled laminated structure corrugated foil structure, the air film pressure is dispersed on the double-layer corrugated foil, effectively dispersing the air film pressure and avoiding overload of a single corrugated foil. A convex structure and a connecting part are set on the double-layer coupled laminated structure corrugated foil, so that each part of the double-layer corrugated foil forms a gradient buffer for the air film. This gradient can make the air film pressure distribution more reasonable, avoid local high-pressure areas, and enhance the bearing capacity of the radial dynamic pressure air bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the overall structure of the radial dynamic pressure air bearing provided by the present invention.

[0019] Figure 2 The present invention provides a schematic structural diagram of a bottom foil and a double-layer corrugated foil in a radial dynamic pressure air bearing.

[0020] Figure 3 This is a schematic diagram of the three-dimensional structure of the bottom foil and the double-layer corrugated foil in the radial dynamic pressure air bearing provided by the present invention.

[0021] Figure 4 The present invention is a schematic structural diagram of the flattened bottom foil and double-layer corrugated foil in the radial dynamic pressure air bearing provided by the present invention.

[0022] Figure 5 The present invention is a schematic structural diagram of a double-layer corrugated foil in a radial dynamic pressure air bearing provided by the present invention being flattened.

[0023] In the figure, 1, bearing seat, 2, bottom foil, 3, first wave foil, 4, second wave foil, 5, double-layer wave foil, 6, sleeve, 7, first protrusion, 8, second protrusion, 9, first connecting part, 10, third protrusion, 11, fourth protrusion, 12, second connecting part. DETAILED DESCRIPTION

[0024] Several embodiments of the present application will be disclosed below with diagrams to clearly and completely describe the technical solution of the present invention. The drawings in the specification are used to provide a further understanding of the present invention. The schematic embodiments and descriptions of the present invention are used to explain the present invention and do not constitute improper limitations on the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0025] It should be noted that unless a direction is defined separately, the directions such as up, down, left, and right mentioned in this document are based on the embodiments of this application. Figure 1The directions of up, down, left, right, etc. shown in the figure shall prevail. If the specific posture changes, the directional indication will also change accordingly. The words "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. In addition, in various embodiments of the present disclosure, the same or similar reference numerals represent the same or similar components.

[0026] In the present invention, unless otherwise clearly defined and specified, the terms "connection", "fixation" and the like 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 defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] 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 fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0028] Example 1 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, it includes a bearing seat 1, a bottom foil 2 and a sleeve 6, the sleeve 6 is sleeved on the outside of the rotating shaft, the bottom foil 2 is arranged between the bearing seat 1 and the sleeve 6, a double-layered bump foil 5 is arranged on the inner side of the bottom foil 2, and the double-layered bump foil 5 includes a first bump foil 3 and a second bump foil 4 which are stacked, and the second bump foil 4 and the first bump foil 3 are stacked on the bottom foil 2 in sequence from the inside to the outside; The first corrugated foil 3 comprises a plurality of first protrusions 7 and second protrusions 8 connected to each other, and the first protrusions 7 and the second protrusions 8 are both protruded away from the bottom foil 2; The second corrugated foil 4 comprises a plurality of interconnected third protrusions 10 and fourth protrusions 11, and the third protrusions 10 and the fourth protrusions 11 are both protruded toward the bottom foil 2; Furthermore, the first protrusion 7 is stacked on the third protrusion 10 , and the second protrusion 8 is stacked on the fourth protrusion 11 .

[0029] The present invention provides a double-layer coupled laminated corrugated foil in the radial dynamic pressure air bearing, and the protrusions designed on the double-layer corrugated 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 bearing capacity and stability of the radial dynamic pressure air bearing. The elastic superposition of the double-layer corrugated foil 5 can better provide gradient buffering, better cope with complex operating conditions, and reduce damage to the bearing and the rotating shaft.

[0030] Example 2 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 1 in that: In the double-layer corrugated foil 5 structure, one end of the first corrugated foil 3 and one end of the second corrugated foil 4 are fixed together and then fixed to the inner side of the bottom foil 2; the other end of the first corrugated foil 3 and the other end of the second corrugated foil 4 are fixed together and are in a free state and are not fixed on the bottom foil 2.

[0031] Such a design can avoid misalignment of the stacked structure caused by friction between the double-layer corrugated foils under variable load conditions, and better maintain the double-layer coupled stacked corrugated foil structure to ensure the load-bearing capacity of the air bearing.

[0032] Example 3 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 1 in that: A first connection portion 9 is disposed between the first protrusion 7 and the second protrusion 8, and the first connection portion 9 is alternately disposed between the first protrusion 7 and the second protrusion 8 along the circumferential direction of the radial dynamic pressure air bearing; And / or, the second connection portion 12 is disposed between the third protrusion 10 and the fourth protrusion 11 , and the second connection portion 12 is alternately disposed between the third protrusion 10 and the fourth protrusion 11 along the circumferential direction of the radial dynamic pressure air bearing.

[0033] The first connection part 9 and the second connection part 12 are alternately arranged in the circumferential direction, which plays a role in increasing the structural stability of the double-layer corrugated foil 5. It not only makes the structure of the double-layer corrugated foil 5 in the circumferential direction more continuous and stable, but also can further enhance the dynamic pressure effect by changing the air flow path, and further improve the bearing capacity of the air bearing.

[0034] Example 4 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 3 in that: The first protrusion 7 is stacked on the third protrusion 10 and the second connection parts 12 on both sides; the second protrusion 8 and the first connection parts 9 on both sides are stacked on the fourth protrusion 11.

[0035] On the one hand, this stacking method can evenly transfer the load to each part of the double-layer corrugated foil 5, avoid local stress concentration, and improve the bearing capacity and reliability of the bearing. On the other hand, through this stacking structure, the double-layer corrugated foil 5 supports each other, increasing the overall rigidity of the double-layer corrugated foil 5 and ensuring the stability of the dynamic pressure air film.

[0036] Example 5 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 3 in that: The first protrusion 7, the first connecting portion 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; And / or, the third protrusion 10 , the second connecting portion 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 .

[0037] The arc-shaped structural design can avoid or reduce the phenomenon of load-bearing force concentration. When bearing a load, the arc-shaped structure can disperse the load-bearing force more evenly, thereby increasing the fatigue life of the double-layer corrugated foil 5 .

[0038] The chord length of the first protrusion 7 is greater than the chord length of the second protrusion 8 and the height is higher. 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 load-bearing structure; the first protrusion 7 and the fourth protrusion 11 provide initial stiffness to resist low-frequency vibrations. As the rotation speed increases, the second protrusion 8 and the third protrusion 10 successively participate in deformation to absorb high-frequency impacts, thereby improving the bearing capacity and adaptability of the bearing.

[0039] Example 6 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 5 in that: like Figure 2 and Figure 1 As shown, the distance between the top of the second protrusion 8 and the bottom foil 2 is greater than the distance between the top of the second connecting portion 12 and the bottom foil 2; And / or, the distance between the top of the third protrusion 10 and the bottom foil 2 is smaller than the distance between the top of the first connecting portion 9 and the bottom foil 2 .

[0040] Such a design can optimize the load distribution on the double-layer corrugated foil 5, which is more scientific and reasonable.

[0041] Example 7 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 2 in that: The structures of the first protrusion 7 and the fourth protrusion 11 are identical, the structures of the second protrusion 8 and the third protrusion 10 are identical, and the structures of the first connecting portion 9 and the second connecting portion 12 are identical.

[0042] This design makes the circumferential lengths of the first corrugated foil 3 and the second corrugated foil 4 the same. When subjected to the air film pressure, they can evenly share the load, avoiding local stress concentration, thereby improving the overall bearing capacity of the double-layer corrugated foil 5; and it is convenient for design, processing and installation.

[0043] Example 8 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 1 in that: like Figure 3 As shown, a plurality of double-layer bump foils 5 are sequentially arranged on the inner side of the bottom foil 2 along the circumferential direction.

[0044] Example 9 This embodiment provides a radial dynamic pressure air bearing with a double-layer coupled laminated corrugated foil, which is different from the embodiment 1 in that: like Figure 3 As shown, a plurality of double-layer bump foils 5 are sequentially arranged on the inner side of the bottom foil 2 along the axial direction.

[0045] The working principle of the above-mentioned radial dynamic pressure air bearing is: when the rotating shaft is not floating, the first protrusion 7 in the first corrugated foil 3 is stacked on the third protrusion 10 and the second connecting part 12, the second protrusion 8 and the first connecting part 9 are stacked on the fourth protrusion 11, and the fourth protrusion 11 is in contact with the bottom foil 2.

[0046] In the working state, an air film is formed between the sleeve 6 and the rotating shaft, and the air film further squeezes the double-layer corrugated foil 5. The first corrugated foil 3 and the second corrugated foil 4 can bear the air film pressure from two directions, and under the action of the first connecting part 9 and the second connecting part 12, the interaction between the various structures of the double-layer corrugated foil 5 forms a gradient support, so that the air bearing can withstand a larger load.

[0047] Example 10 A motor, characterized in that it includes the radial dynamic pressure air bearing provided in the above-mentioned embodiments 1-9.

[0048] The above description shows and describes the preferred embodiments of the present application. However, as mentioned before, 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 changed within the scope conceived herein through the above teachings or the technology or knowledge in the relevant field. And any changes and variations 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 dynamic pressure air bearing with double-layer coupled laminated corrugated foil, characterized in that: The invention comprises a bearing seat, a bottom foil and a sleeve, wherein the sleeve is sleeved on the outside of the rotating shaft, the bottom foil is arranged between the bearing seat and the sleeve, a double-layer corrugated foil is arranged on the inner side of the bottom foil, the double-layer corrugated foil comprises a first corrugated foil and a second corrugated foil which are stacked, and the second corrugated foil and the first corrugated foil are stacked on the bottom foil in sequence from the inside to the outside; The first corrugated foil comprises a plurality of first protrusions and second protrusions connected to each other, wherein the first protrusions and the second protrusions are protruded in a direction away from the bottom foil; The second corrugated foil comprises a plurality of third protrusions and fourth protrusions connected to each other, wherein the third protrusions and the fourth protrusions both protrude toward the bottom foil; Furthermore, the first protrusion is stacked on the third protrusion, and the second protrusion is stacked on the fourth protrusion.

2. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated 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. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 1, characterized in that: A first connection portion is disposed between the first protrusion and the second protrusion, and the first connection portion is alternately disposed between the first protrusion and the second protrusion along the circumferential direction of the radial dynamic pressure air bearing; And / or, a second connection portion is disposed between the third protrusion and the fourth protrusion, and the second connection portion is alternately disposed between the third protrusion and the fourth protrusion along the circumferential direction of the radial dynamic pressure air bearing.

4. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 3, characterized in that: The first protrusion is stacked on the third protrusion and the second connection parts on both sides; the second protrusion and the first connection parts on both sides are stacked on the fourth protrusion.

5. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 3, 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.

6. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 5, characterized in that: The distance between the top of the second protrusion and the bottom foil is greater than the distance between the top of the second connecting portion and the bottom foil; And / or, the distance between the top of the third protrusion and the bottom foil is smaller than the distance between the top of the first connecting portion and the bottom foil.

7. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 2, characterized in that: The structures of the first protrusion and the fourth protrusion are identical to each other, the structures of the second protrusion and the third protrusion are identical to each other, and the structures of the first connecting portion and the second connecting portion are identical to each other.

8. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 1, characterized in that: A plurality of double-layer corrugated foils are arranged in sequence along the circumferential direction on the inner side of the bottom foil.

9. A radial dynamic pressure air bearing with double-layer coupled laminated corrugated foil according to claim 1, characterized in that: A plurality of double-layer corrugated foils are arranged in sequence along the axial direction on the inner side of the bottom foil.

10. A motor, characterized in that: A radial foil gas dynamic pressure bearing comprising any one of claims 1 to 9.

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