Air bearing supported by elastic damper

Abstract

The application discloses an air bearing supported by elastic dampers, which comprises a bearing seat and a top foil arranged in the bearing seat, and a plurality of dampers are arranged in the bearing seat and the top foil in a ring shape, wherein the dampers comprise a fixed block and a movable block in sliding fit, a disc spring is arranged between the fixed block and the movable block, the fixed block is fixed to the bearing seat, the movable block can slide along the radial direction of the bearing, and the movable block is close to the fixed block after the disc spring is compressed; and the end face of the movable block towards the top foil is V-shaped and has two planes tangent to the top foil. The air bearing uses the dampers to replace traditional wave foils to perform elastic support, and the disc spring will not be plastically deformed in the whole life cycle. In addition, the end face of the movable block towards the top foil is V-shaped and has two planes tangent to the top foil, and the top foil and the plane will slide relatively during operation, so that Coulomb friction is generated, and the stability of the shaft system is improved.

Description

Technical Field

[0001] This invention relates to the field of air bearing technology, and more particularly to an air bearing supported by an elastic damper. Background Technology

[0002] Foil air bearings are self-acting hydrodynamic air bearings that use air as a lubricating medium. Compared with traditional high-speed bearings, they have advantages such as simple structure, high speed, low friction power consumption, resistance to high and low temperatures, good stability, and convenient maintenance. They are gradually being further applied and developed in fields such as air-suspended centrifugal blowers, electronic turbochargers, and compressors for hydrogen fuel cells, and have broad application prospects in the future field of high-speed rotating machinery.

[0003] Existing radial foil hydrodynamic air bearings consist of a top foil and a corrugated foil. The corrugated foil is placed inside the bearing housing bore and circumferentially adheres to the bore wall. The top foil is placed inside the corrugated foil and circumferentially adheres to it. Neither the top foil nor the corrugated foil is closed circumferentially; both are open structures. One end is called the free end, and the other end is called the fixed end. When the bearing is under load, the corrugated foil undergoes elastic deformation in the load-bearing area. The free movement of the top foil's free end along the circumferential direction matches the deformation of the corrugated foil, ensuring stable bearing capacity and improving the stability of the shaft system.

[0004] Corrugated sheets are used as elastic supports in air bearings, such as the foil-type air hydrodynamic bearing disclosed in Chinese Utility Model No. 201921053369.3. Corrugated sheets have advantages such as simple structure and strong versatility. However, they also have some unavoidable problems during use. For example, the corrugated sheets are made of very thin sheets pressed by a mold, with a sheet thickness of about 0.05 to 0.2 mm. This leads to the risk of plastic deformation of the corrugated sheets during long-term use. Due to the plastic deformation of the corrugated sheet structure, the outline dimensions of the corrugated sheet deviate from the original design values, which changes the performance of the air bearing, such as reduced load-bearing capacity and worsened shaft system running stability. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an air bearing supported by an elastic damper, which can avoid the problem of plastic deformation of the corrugated foil.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] An air bearing supported by elastic dampers includes a bearing housing and a top foil placed inside the bearing housing. The bearing housing and the top foil are characterized by having a plurality of annularly distributed dampers. Each damper includes a fixed block and a movable block that slide together. A disc spring is provided between the fixed block and the movable block. The fixed block is fixed to the bearing housing. The movable block can slide radially along the bearing and approaches the fixed block after compressing the disc spring. The end face of the movable block facing the top foil is V-shaped and has two planes tangent to the top foil.

[0008] A further technical solution is that: the inner wall of the bearing seat has a groove that fits into the fixing block, the groove is axially through, the width of its outer radial end is greater than the width of its inner end, and the two ends of the bearing seat are detachably fixed with retaining rings, which can axially limit the fixing block.

[0009] A further technical solution is that the cross-sectional shape of the groove is T-shaped, trapezoidal, or mushroom-shaped.

[0010] A further technical solution is that: the fixed block has multiple axially arranged sliding grooves, the movable block has sliding columns matching the number of sliding grooves, each sliding column is slidably connected to a sliding groove, and the disc spring is located at the bottom of the sliding groove.

[0011] A further technical solution is that: the middle part of the slide groove has a guide post, the middle part of the slide post has a guide hole that slides and engages with the guide post, and the disc spring is sleeved on the guide post.

[0012] A further technical solution is that the number of disc springs is one or more, and multiple disc springs are stacked or paired.

[0013] A further technical solution is that: the bearing seat has retaining rings detachably fixed at both ends, the inner edge of the retaining ring can block and limit the end of the top foil, the inner edge of the retaining ring has a notch, and the fixed end of the top foil has a fixing part located in the notch.

[0014] A further technical solution involves having a notch on the retaining ring between two adjacent dampers.

[0015] A further technical solution is that the thickness of the top foil is 0.5mm to 3mm.

[0016] A further technical solution is that the end face of the movable block facing the top foil has a wear-resistant coating.

[0017] The beneficial effects of adopting the above technical solution are as follows:

[0018] This air bearing uses a damper instead of traditional corrugated foil for elastic support. The damper uses a disc spring to provide elastic deformation. The biggest advantage is that it has high stiffness. The disc spring will not undergo plastic deformation throughout its entire lifespan. Even if the disc spring is flattened, it can still return to its original shape after the external load is removed. Therefore, there is no problem of plastic deformation of the disc spring, which effectively improves the service life of the bearing.

[0019] In addition, the end face of the moving block in the damper facing the top foil is V-shaped and has two planes tangent to the top foil. During operation, the top foil and this plane will slide relative to each other, thereby generating Coulomb friction, which consumes the energy brought by the shaft system during operation, thereby improving the stability of the shaft system operation. Attached Figure Description

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] Figure 1 This is a schematic diagram of the isometric structure of the bearing in this invention;

[0022] Figure 2 This is a schematic diagram of the main structure of the bearing in this invention;

[0023] Figure 3 This is a schematic diagram of the bearing structure after the retaining rings at both ends are removed in this invention;

[0024] Figure 4 This is a schematic diagram of the first structure of the bearing housing in this invention (the cross-section of the groove is mushroom-shaped);

[0025] Figure 5 This is a schematic diagram of the second structural design of the bearing housing in this invention (the transverse cross-section of the groove is T-shaped).

[0026] Figure 6 This is a schematic diagram of the third structure of the bearing housing in this invention (the cross-section of the groove is trapezoidal).

[0027] Figure 7 This is a schematic diagram of the isometric structure of the damper in this invention;

[0028] Figure 8 This is a schematic cross-sectional view of the damper in this invention;

[0029] Figure 9 This is a schematic diagram of the structure of the fixed block in the damper of the present invention;

[0030] Figure 10 This is a schematic diagram of the structure of the movable block in the damper of the present invention;

[0031] Figure 11 This is a schematic diagram of the retaining ring structure in this invention;

[0032] Figure 12This is a schematic diagram of the top foil structure in this invention;

[0033] Figure 13 This is a schematic diagram of the structure of multiple disc springs stacked together in this invention;

[0034] Figure 14 This is a schematic diagram of the structure after multiple disc springs are engaged in this invention. Detailed Implementation

[0035] 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 some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0037] like Figures 1 to 14 As shown, an air bearing supported by elastic dampers includes a bearing housing 1 and a top foil 2 placed inside the bearing housing 1. A plurality of dampers 3 are evenly distributed in a ring between the bearing housing 1 and the top foil 2. Each damper 3 includes a fixed block 31 and a movable block 32 that are slidably engaged. A disc spring 33 is provided between the fixed block 31 and the movable block 32. The fixed block 31 is fixed to the bearing housing 1. The movable block 32 can slide along the radial direction of the bearing and approaches the fixed block 31 after compressing the disc spring 33. The end face of the movable block 32 facing the top foil 2 is V-shaped and has two planes tangent to the top foil 2.

[0038] This air bearing uses a damper 3 instead of a traditional corrugated foil for elastic support. The damper 3 uses a disc spring 33 to provide elastic deformation. The biggest advantage is that it has greater stiffness. The disc spring 33 will not undergo plastic deformation throughout its entire lifespan. Even if the disc spring 33 is flattened, it can still return to its original shape after the external load is removed. Therefore, the disc spring 33 does not have the problem of plastic deformation, which effectively improves the service life of the bearing.

[0039] In addition, the end face of the movable block 32 in the damper 3 facing the top foil 2 is V-shaped and has two planes tangent to the top foil 2. During operation, the top foil and the plane will slide relative to each other, thereby generating Coulomb friction, which consumes the energy brought by the shaft system during operation, thereby improving the stability of the shaft system operation.

[0040] Regarding the fixing method between the fixing block 31 and the bearing housing 1, a concave-convex fitting method can be used to facilitate later inspection and maintenance of the bearing. The inner wall of the bearing housing 1 has a groove 101 that engages with the fixing block 31. The groove 101 is axially continuous, and the fixing block 31 slides axially into the groove 101. The width of the outer end of the groove 101 is greater than the width of the inner end. Figures 4-6 As shown, the cross-sectional shape of the groove 101 is T-shaped, trapezoidal, or mushroom-shaped, which can radially limit the fixing block 31. Moreover, the retaining rings 4 are detachably fixed at both ends of the bearing seat 1 by bolts, and the retaining rings 4 can axially limit the fixing block 31.

[0041] like Figures 7-10 As shown, in one specific form of the damper 3, the fixed block 31 has multiple axially arranged grooves 311, and the movable block 32 has sliding columns 321 matching the number of grooves 311. Each sliding column 321 slides into a groove 311, and a disc spring 33 is disposed at the bottom of the groove 311. Through the cooperation of the grooves 311 and the sliding columns 321, the movable block 32 can slide radially. After the bearing bears a load, the disc spring 33 is compressed radially outward to achieve elastic deformation, allowing the free end of the top foil to move freely in the circumferential direction and match the deformation of the corrugated foil to ensure that the bearing can stably bear the load and improve the stability of the shaft system operation.

[0042] In addition, a guide post 312 is provided in the middle of the slide groove 311, and a guide hole 322 is provided in the middle of the slide post 321 to slide and engage with the guide post 312. The disc spring 33 is sleeved on the guide post 312, and the guide post 312 guides the disc spring 33.

[0043] like Figure 13 and Figure 14 As shown, there are one or more disc springs 33, which can be stacked or paired. Disc springs 33 can be used individually or in combination. Stacking several sets of disc springs 33 increases their stiffness, while pairing several sets decreases their stiffness, thus providing different elastic forces. Whether the disc springs 33 are stacked or paired depends on the actual design, but combined use increases the overall Coulomb friction of the bearing and improves the stability of the shaft system.

[0044] To reduce rotor starting torque, decrease wear, and extend bearing life, a wear-resistant coating is applied to the end face of the movable block 32 facing the top foil 2. This wear-resistant layer is either a molybdenum disulfide coating or a polytetrafluoroethylene coating, and can be formed by spraying. The thickness of the wear-resistant layer is 0.02–0.03 mm.

[0045] Retaining rings 4 are detachably fixed at both ends of the bearing housing 1, such as... Figure 11As shown, the retaining ring 4 is a conventional bearing structure. The special feature of the retaining ring 4 in this structure is that its inner edge can block and limit the end of the top foil 2, and can axially limit the damper 3 and the top foil 2. Additionally, a notch is provided on the inner edge of the retaining ring 4, such as... Figure 12 As shown, the fixed end of the top foil 2 has a fixing part 201 located in the notch. The circumferential fixing of the fixed end of the top foil 2 is achieved by snapping the fixing part 201 into the notch.

[0046] The air bearing supported by the elastic damper disclosed herein uses a thick top foil 2 with a thickness of 0.5 mm to 3 mm. This avoids the problem of the top foil sinking under heavy load or impact load, increases the damping of the bearing, and further improves the smoothness of bearing operation.

[0047] Additionally, there is a notch 401 on the retaining ring 4 between two adjacent dampers 3, which can be used for heat dissipation.

[0048] The above are merely preferred embodiments of the present invention. Any simple modifications, variations, and equivalent substitutions made by any person based on the content of the present invention shall fall within the protection scope of the present invention.

Claims

1. An air bearing supported by an elastic damper, comprising a bearing housing (1) and a top foil (2) disposed within the bearing housing (1), characterized in that: Between the bearing housing (1) and the top foil (2), there are a plurality of annularly distributed dampers (3). Each damper (3) includes a fixed block (31) and a movable block (32) that are in sliding engagement. A disc spring (33) is provided between the fixed block (31) and the movable block (32). The fixed block (31) is fixed to the bearing housing (1). The movable block (32) can slide along the bearing radial direction and approach the fixed block (31) after compressing the disc spring (33). The end face of the movable block (32) facing the top foil (2) is V-shaped and has two planes tangent to the top foil (2).

2. The air bearing according to claim 1, characterized in that: The bearing seat (1) has a groove (101) on its inner wall that fits into the fixing block (31). The groove (101) is axially through, and the width of its outer radial end is greater than the width of its inner end. The bearing seat (1) is detachably fixed with retaining rings (4) at both ends. The retaining rings (4) can axially limit the fixing block (31).

3. The air bearing according to claim 2, characterized in that: The cross-sectional shape of the groove (101) is T-shaped, trapezoidal, or mushroom-shaped.

4. The air bearing according to claim 1, characterized in that: The fixed block (31) has multiple axially arranged sliding grooves (311), and the movable block (32) has sliding columns (321) matching the number of sliding grooves (311). Each sliding column (321) is slidably connected to a sliding groove (311), and the disc spring (33) is located at the bottom of the sliding groove (311).

5. The air bearing according to claim 4, characterized in that: The middle part of the slide groove (311) has a guide post (312), the middle part of the slide post (321) has a guide hole (322) that slides and engages with the guide post (312), and the disc spring (33) is sleeved on the guide post (312).

6. The air bearing according to claim 1, characterized in that: The number of disc springs is one or more, and multiple disc springs (33) are stacked in the same direction or opposite to each other.

7. The air bearing according to claim 1, characterized in that: The bearing seat (1) is detachably fixed with retaining rings (4) at both ends. The inner edge of the retaining rings (4) can block and limit the end of the top foil (2). The inner edge of the retaining rings (4) is provided with a notch. The fixed end of the top foil (2) has a fixing part (201) located in the notch.

8. The air bearing according to claim 7, characterized in that: The retaining ring (4) between two adjacent dampers (3) has a notch (401).

9. The air bearing according to claim 1, characterized in that: The thickness of the top foil (2) is 0.5 mm to 3 mm.

10. The air bearing according to claim 1, characterized in that: The active block (32) has a wear-resistant coating on the end face facing the top foil (2).

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