Foil assemblies, foil bearings, air compressors
By using through-groove and bending sheet structures in foil assembly for positioning and clamping of foils, the shortcomings of traditional welding and pin fixing methods in multi-layer foil bearings are solved, and a more stable and convenient assembly process is achieved. , improves the performance and reliability of bearings.
Patent Information
- Application Number
- CN202111537833.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-15
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2041-12-15
AI Technical Summary
The traditional welding and pin fixing methods have problems such as increasing load dead zones, axial foil tweaking and increasing bearing seat size in multi-layer foil bearings, which cannot meet the performance improvement and maintenance requirements.
Using a component design including a fixed outer ring, a top foil and an arched foil, the positioning and clamping of the foil is simplified by the structure of the first through groove and the second through groove, the positioning and clamping of the foil is simplified by the bending sheet. Avoid the disadvantages of welding and pins.
It effectively overcomes the shortcomings of welding and pin fixing methods, improves the stability and assembly convenience of foil components, reduces maintenance complexity and size increase problems, and improves the performance and reliability of bearings.
Smart Images
Figure CN114087279B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of foil bearing design, and in particular relates to a foil assembly, a foil bearing and an air compressor. Background Art
[0002] Conventional full-circle foil bearings are divided into three parts: a top foil, an arched foil and a bearing seat. The simplest foil bearing is composed of a layer of top foil and a layer of arched foil. For this type of foil bearing, the conventional assembly method is to fix the top foil and the arched foil directly to the bearing seat, and the most common fixing methods are welding and pin fixing. As the research on foil bearings becomes more and more in-depth and its performance is continuously optimized, foil bearings composed of a layer of top foil and a layer of arched foil can no longer meet people's use needs. Therefore, the performance of foil bearings is improved by increasing the number of foil layers. As the number of layers increases, the disadvantages of the welding and pin fixing methods become more and more apparent.
[0003] Among them, welding requires the use of special welding equipment to extend into the inner ring of the bearing seat for welding. Generally, the foil is in a free state in the inner ring of the bearing seat during welding. Therefore, whether it is single-piece welding or double-layer stacking welding, there will be problems with loose welding, and the double-layer stacking welding has a higher false welding rate and the welding effect is not ideal. Therefore, staggered welding is often used. As the number of foil layers increases, the staggered welding form will increase the bearing "dead zone" of the bearing, resulting in a decrease in the bearing's load-bearing characteristics. In addition, if the foil needs to be replaced by welding, the entire bearing needs to be replaced.
[0004] The pin fixation method is easily affected by the actual dimensions of components such as the pin, bearing seat fixing hole and foil thickness. It is easy for the pin to be too tight and unable to be inserted, or the clearance fit may cause the pin to loosen during use. In addition, the axial movement of the foil is also prone to occur during the pin insertion process. The pin fixation method will increase the size of the bearing seat, making the size of the bearing position larger, which will increase the overall size of the prototype. Summary of the invention
[0005] Therefore, the present invention provides a foil assembly, a foil bearing, and an air compressor, which can overcome the shortcomings of traditional welding and pinning methods of fixing foils in multi-layer foil bearings, such as increased load-bearing dead zone, axial movement of the foil, and increased bearing seat size.
[0006] In order to solve the above problems, the present invention provides a foil assembly, including a fixed outer ring, at least one layer of top foil, and at least one layer of arched foil, the fixed end of the top foil is configured with a first through groove, the fixed end of the arched foil is configured with a second through groove, the fixed outer ring has a first end and a second end, the second end is provided with a first bending piece, the free end of the first bending piece can pass through the first through groove and the second through groove in sequence to achieve the positioning and clamping of the top foil and the arched foil by the first end and the second end.
[0007] In some embodiments, a fixing groove is configured on the first end, and the free end of the first bending piece can be embedded in the fixing groove after passing through the first through groove and the second through groove.
[0008] In some embodiments, the fixing groove is a through groove.
[0009] In some embodiments, the fixed outer ring has an outer ring portion between the first end and the second end, the first end has a second bending piece, the second end has a third bending piece, the second bending piece and the third bending piece are parallel to each other, the first bending piece is on the side of the third bending piece away from the outer ring portion, and the fixing groove is constructed on the second bending piece.
[0010] In some embodiments, the first end further has a fourth bending piece parallel to the second bending piece, the fourth bending piece is located outside the third bending piece, and the fourth bending piece can prevent the first bending piece from escaping from the fixing groove.
[0011] In some embodiments, at the axial end of the fixed outer ring, the third bending piece and the fourth bending piece respectively have a first bending mark at the connection with the outer ring portion.
[0012] In some embodiments, the top foil has at least two layers, and the bent portion between the top foil ring portion and the fixed end of each layer of the top foil is sequentially attached from inside to outside along the radial direction of the fixed outer ring.
[0013] In some embodiments, when the first bending piece passes through the first through groove and the second through groove, the first bending piece can apply force to the fixed ends of the top foil and the arched foil in a radial direction away from the fixed outer ring.
[0014] In some embodiments, the thickness of the first bending piece is d, the radial width of the first through groove is a, 1.1d≥a>d, and / or the radial width of the second through groove is b, 1.1d≥b>d.
[0015] The present invention also provides a foil bearing, comprising a bearing seat and a foil assembly, wherein the foil assembly is the above-mentioned foil assembly.
[0016] The present invention also provides an air compressor, comprising the above-mentioned foil bearing.
[0017] The present invention provides a foil assembly, a foil bearing, and an air compressor. The first bent sheet of the fixed outer ring can fix and position at least one layer of top foil and the arched foil after stacking as a whole and then assemble and fix them with the bearing seat, which can simplify the fixation of the foil in the foil assembly and the assembly process between the foil assembly and the bearing seat, and effectively overcome the shortcomings of the prior art when using welding and pins to fix multiple layers of foil. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 is a schematic diagram of the three-dimensional structure of a foil assembly according to an embodiment of the present invention;
[0019] Figure 2 for Figure 1 A partial enlarged view of the middle A;
[0020] Figure 3 for Figure 1 Schematic diagram of the assembly structure of the top foil and the arched foil;
[0021] Figure 4 for Figure 1 A schematic diagram of a partial structure of a foil assembly in FIG.
[0022] Figure 5 for Figure 1 Schematic diagram of the assembly of the foil assembly;
[0023] Figure 6 FIG. 4 is a schematic diagram of a partial structure of a foil bearing according to another embodiment of the present invention.
[0024] The reference numerals are as follows:
[0025] 1. Fixed outer ring; 11. Fixed groove; 12. First bending piece; 13. Second bending piece; 14. Third bending piece; 15. Fourth bending piece; 16. First bending mark; 2. Arched foil; 3. Top foil; 31. First through groove; 32. Second bending mark; 4. Bearing seat; 41. Assembly groove. DETAILED DESCRIPTION
[0026] See also Figures 1 to 6As shown, according to an embodiment of the present invention, a foil assembly is provided, comprising a fixed outer ring 1, at least one layer of top foil 3, and at least one layer of arched foil 2, wherein the fixed end of the top foil 3 is configured with a first through groove 31, and the fixed end of the arched foil 2 is configured with a second through groove (not shown in the figure and not labeled), the fixed outer ring 1 has a first end and a second end, and the second end has a first bending piece 12, and the free end of the first bending piece 12 can sequentially pass through the first through groove 31 and the second through groove to achieve the first end and the second end to position and clamp the top foil 3 and the arched foil 2. In this technical solution, the first bending piece 12 of the fixed outer ring 1 can fix and position the at least one layer of top foil 3 and the arched foil 2 after being stacked as a whole, and then assemble and fix them with the bearing seat 4, which can simplify the fixing of the foil in the foil assembly and the assembly process between the foil assembly and the bearing seat 4, and effectively overcome the shortcomings of the prior art when welding and pinning are used to fix multiple layers of foil.
[0027] In some embodiments, a fixing groove 11 is configured on the first end, and the free end of the first bending piece 12 can be embedded in the fixing groove 11 after passing through the first through groove 31 and the second through groove, which can improve the stability and reliability of the first end and the second end clamping the foil. Furthermore, the fixing groove 11 is a through groove, thereby reducing the difficulty of manufacturing the fixing groove 11.
[0028] In a specific embodiment, the fixed outer ring 1 has an outer ring portion between the first end and the second end, the first end has a second bending piece 13, the second end has a third bending piece 14, the second bending piece 13 and the third bending piece 14 are parallel to each other, the first bending piece 12 is on the side of the third bending piece 14 away from the outer ring portion, and the fixing groove 11 is constructed on the second bending piece 13. It can be understood that at this time, the clamping of the foil by the first end and the second end is specifically achieved through the second bending piece 13 and the third bending piece 14.
[0029] The first end also has a fourth bending piece 15 parallel to the second bending piece 13, and the fourth bending piece 15 is located on the outside of the third bending piece 14. The fourth bending piece 15 can prevent the first bending piece 12 from escaping from the fixing groove 11. The fourth bending piece 15 can further reinforce the position of the first bending piece 12 to further ensure the reliability of clamping and reinforcement.
[0030] It is understandable that in order to ensure smooth assembly of the top foil 3 and the arched foil 2 , the fixed outer ring 1 should be made of a material with a certain elastic deformation capability.
[0031] On the axial end of the fixed outer ring 1, the third bending piece 14 and the fourth bending piece 15 are respectively connected to the outer ring part with a first bending mark 16 to guide the operator to manufacture the fixed outer ring 1. It should be noted that the position of the first bending mark 16 needs to be determined according to the inner circumference of the bearing chamber and the specific number of foil layers of the bearing, and then finally determined according to empirical values. Preferably, the best assembly state is that there is a small gap between the fixed outer ring 1 and the inner circle of the bearing chamber, and the assembly needs to be heated after installation and then taken out.
[0032] In some embodiments, the top layer foil 3 has at least two layers, and the bent portion between the top foil ring portion and the fixed end of each layer of the top layer foil 3 fits in sequence from the inside to the outside along the radial direction of the fixed outer ring 1, so that the inner and outer layers of the multi-layer top layer foil 3 can be effectively prevented from being confused when assembling. Specifically, since the multi-layer top layer foil 3 needs to be arranged in sequence from the inside to the outside along the radial direction of the bearing during assembly, the bending radius at the bent portion of each layer of the top layer foil 3 will decrease (radially from inside to outside) due to the thickness of each layer of the top layer foil 3. When the multi-layer top layer foil 3 needs to be assembled, if the inner and outer layers of the top layer foil 3 are placed upside down, the bent portions of the two top layer foils 3 will not fit together, and then the operator is prompted to swap the number of layers of the top layer foil 3, that is, the position of the inner and outer sides, to achieve an error-proofing effect during assembly.
[0033] Preferably, when the first bending piece 12 passes through the first through groove 31 and the second through groove, the first bending piece 12 can apply force to the fixed ends of the top foil 3 and the arched foil 2 in a radial direction away from the fixed outer ring 1, ensuring that the fixed ends of each layer of foil have an outward pulling force after assembly, so that they are in an inward tightened state. The advantages of such a setting are, first, to ensure that the fixed ends of each layer of foil will not exceed the inner circular surface of the top foil 3 inward, avoiding interference friction between the fixed ends of the bearing and the rotor during the rotation and operation, leading to The first is that the reliability caused by local friction is reduced; the second is that the fixed end of each layer of foil has an outward pulling force after the assembly is completed, and is in an inward tightened state, which can have a certain damping when assembling the bearing, ensuring that the first bending piece 12 of the fixed outer ring 1 can be clearly felt when passing through the first through grooves 31 of each layer of foil and the second through grooves are stuck in the fixed groove 11, so that the personnel preparing the bearing can judge whether the bearing is assembled in place. At the same time, when the fourth bending piece 15 is pried when disassembling the bearing, the layers of foil inside the bearing can be automatically ejected, ensuring the convenience of disassembly. In a specific embodiment, a second bending mark 32 is set at one axial end of the top foil 3 or the arched foil 2, and the second bending mark 32 is used as a reference point to determine the relative position between the fixed groove 11 and the first through groove 31 and the second through groove. For example, the distance between the radial outer groove wall of the first through groove 31 and the second through groove and the second bending mark 32 is slightly smaller than the distance between the radial outer groove wall of the fixed groove and the second bending mark 32. Specifically, the distance between the radial outer groove wall of the first through groove 31 and the second through groove and the second bending mark 32 can take a negative tolerance value (-0.03mm to -0.05mm).
[0034] In order to ensure that the first bending piece 12 can smoothly penetrate into the first through groove 31 and the second through groove, the thickness of the first bending piece 12 is d, the radial width of the first through groove 31 is a, 1.1d≥a>d, and / or the radial width of the second through groove is b, 1.1d≥b>d.
[0035] According to an embodiment of the present invention, there is also provided a foil bearing, in particular a multi-layer foil type hydrodynamic bearing, comprising a bearing seat 4 and a foil assembly, wherein the foil assembly is the above-mentioned foil assembly. Figure 6 As shown, an assembly groove 41 is constructed on the inner wall of the bearing chamber of the bearing seat 4. The foil assembly is fixed to the first end and the second end of the outer ring 1 to clamp and position the top foil 3 and the arched foil 2 and then embedded in the assembly groove 41, thereby realizing reliable and convenient assembly between the foil assembly and the bearing chamber.
[0036] According to an embodiment of the present invention, there is also provided an air compressor, comprising the above-mentioned foil bearing.
[0037] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.
[0038] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention, and these improvements and variations should also be regarded as the protection scope of the present invention.
Claims
1. A foil assembly, characterized in that: The invention comprises a fixed outer ring (1), at least one layer of top foil (3), and at least one layer of arched foil (2); the fixed end of the top foil (3) is configured with a first through groove (31), and the fixed end of the arched foil (2) is configured with a second through groove; the fixed outer ring (1) has a first end and a second end, the second end is provided with a first bending piece (12), the free end of the first bending piece (12) can sequentially pass through the first through groove (31) and the second through groove to achieve the positioning and clamping of the top foil (3) and the arched foil (2) by the first end and the second end; the first end is configured with a fixed groove (11), and the free end of the first bending piece (12) can be embedded in the fixed groove (11) after passing through the first through groove (31) and the second through groove; The fixed outer ring (1) has an outer ring portion between the first end and the second end, the first end has a second bending piece (13), the second end has a third bending piece (14), the second bending piece (13) and the third bending piece (14) are parallel to each other, the first bending piece (12) is located on the side of the third bending piece (14) away from the outer ring portion, and the fixed groove (11) is constructed on the second bending piece (13); the first end also has a fourth bending piece (15) parallel to the second bending piece (13), the fourth bending piece (15) is located on the outside of the third bending piece (14), and the fourth bending piece (15) can prevent the first bending piece (12) from escaping from the fixed groove (11); the fixed groove (11) is a through groove.
2. The foil assembly according to claim 1, characterized in that On the axial end of the fixed outer ring (1), the connection between the third bending piece (14) and the fourth bending piece (15) and the outer ring portion is provided with a first bending mark (16).
3. The foil assembly according to claim 1, characterized in that The top foil (3) has at least two layers, and the bent portion between the top foil ring portion and the fixed end of each layer of the top foil (3) is sequentially fitted from the inside to the outside along the radial direction of the fixed outer ring (1).
4. The foil assembly according to claim 1, characterized in that When the first bending piece (12) passes through the first through groove (31) and the second through groove, the first bending piece (12) can exert force on the fixed ends of the top foil (3) and the arched foil (2) in a radial direction away from the fixed outer ring (1).
5. The foil assembly according to claim 4, characterized in that The thickness of the first bending piece (12) is d, the radial width of the first through groove (31) is a, 1.1d≥a>d, and / or the radial width of the second through groove is b, 1.1d≥b>d.
6. A foil bearing, comprising a bearing seat (4) and a foil assembly, characterized in that: The foil assembly is the foil assembly according to any one of claims 1 to 5.
7. An air compressor, characterized in that: The invention comprises the foil bearing as claimed in claim 6.