Novel laminated foil thrust bearing

Abstract

The invention discloses a novel laminated foil thrust bearing. The novel laminated foil thrust bearing comprises a top foil, a plurality of supporting frames, a flat plate and a bottom supporting plate which are sequentially laminated, wherein the top foil is provided with a plurality of annularly arranged working surfaces. The outer ring of the top foil and the outer ring of the flat plate are connected in an overlapped mode, the supporting frame enables working faces of the top foil to form inclined faces in the same direction in the circumferential direction, and the bottom supporting plate enables the supporting faces of the flat plate to form a simply supported beam supporting structure in the circumferential direction. Due to the fact that a bump foil part is omitted, the multiple layers of foil pieces are stacked to form a beam type support, all working faces of the top foil form inclined faces in the same direction, a dynamic pressure gas film is easily formed between the rotor and the bearing, and the bearing and lubricating effects are achieved. The bottom supporting plate forms a simply supported beam supporting structure for the flat plate, the supporting span is increased, the rigidity of the bearing is reduced, and the running stability of the bearing is improved. A precise mold is not needed, and the machining cost is reduced. Parts of the bearing are connected through pins and the like, welding is removed, and the influence of welding thermal deformation on the precision and reliability of the bearing is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the supporting parts in the shafting structure, especially relates to a new type of laminated foil structure thrust bearing for the axial support of high-speed rotors. BACKGROUND

[0002] The foil thrust bearing is more and more widely applied in the field of high-speed rotating machinery due to the characteristics of no oil, no friction in operation, simple maintenance and the like. The foil thrust bearing is mainly used for the axial support of high-speed rotors to reduce the axial movement of the rotors and ensure the reliability of the axial support of the rotors. The current foil thrust bearing is mainly the wave foil type, and the bearing is roughly composed of a top foil, a wave foil (wave foil sheet) and a base plate in turn. The bearing can generate a wedge-shaped dynamic pressure effect by using the wedge-shaped space formed between the rotor bearing disc and the bearing surface, that is, as the rotor speed is continuously improved, the surrounding gas is continuously dragged into the wedge-shaped space formed between the rotor bearing disc and the bearing due to the viscosity of the gas, and the gas pressure in the wedge-shaped space is continuously improved, so that a dynamic pressure gas film is formed between the rotor and the bearing when the bearing speed reaches a certain value, so as to isolate the rotor bearing disc from the bearing, and play a bearing lubrication role. Therefore, it is also called a dynamic pressure gas foil thrust bearing.

[0003] As shown in Figure 1 , the early foil thrust bearing includes a base plate 30, a wave foil 10 and a top foil 20 in turn, and a rotor bearing disc 40 is in contact with the top foil 20 of the bearing. Since there is a wedge-shaped space (left side) between the rotor bearing disc 40 and the top foil 20 of the bearing, when the rotor speed is continuously improved to reach a certain value, a dynamic pressure gas film is formed between the rotor bearing disc 40 and the top foil 20 of the bearing to isolate the rotor bearing disc 40 from the bearing, and play a bearing lubrication role. As can be seen from Figure 1 , the top foil 20 of the bearing and the outer edge size of the wave foil 10 substantially overlap, and when the bearing is working, the dynamic pressure gas leaks from the top edge of the bearing, which causes the bearing capacity of the edge area of the bearing to be insufficient, so that the bearing is easy to wear. As shown in Figure 2 , the bearing has a base plate 500, a wave foil 510 and a top foil 610, and a rotor bearing disc 800. In order to overcome the defect of dynamic pressure gas leakage from the top edge of the bearing, the edge size of the top foil 610 of the bearing is made larger than the edge size of the wave foil 510. When the bearing is working, the gas in the bearing area will not leak from the top foil and the rotor, and will not cause the bearing capacity of the edge area of the bearing to be reduced, thereby avoiding the problem that the edge of the bearing is easy to wear.

[0004] From the above, the existing foil thrust bearing is provided with a damping elastic wave foil between the base plate and the top foil, and the elastic deformation of the wave foil is used to absorb the vibration energy of the dynamic pressure gas film or the rotor, that is, to increase the damping of the bearing, reduce the stiffness of the bearing, and improve the stability of the rotor operation. The lower the stiffness of the wave foil, the stronger the damping capacity, the stronger the ability of the bearing to absorb vibration, and the more stable the operation of the rotor. However, the lower the stiffness of the wave foil, the greater the deformation, which is easy to cause irreversible plastic deformation of the wave foil, thereby losing the damping effect. In addition, the foil thrust bearing works by using the gas film effect, and the gas film thickness is in the micron level, so the machining precision of the wave foil and other parts is relatively high. The wave foil is usually made by precision stamping, and the precision of the stamping die is very high, which increases the cost of the die. At the same time, after the die is used for stamping production for a period of time, it will be worn, which will cause the precision of the wave foil to be poor, and it is easy to cause the precision of the bearing to be unstable, thereby reducing the reliability of the bearing. In addition, the foils of the foil thrust bearing are usually connected to each other by welding, which is easy to cause thermal deformation of the foils, reduce the forming precision of the foils, and affect the reliability of the bearing.

[0005] Therefore, how to overcome the defects of the existing foil thrust bearing, such as plastic deformation of the wave foil, reduction of the manufacturing precision of the wave foil, high manufacturing cost of the foil thrust bearing, and influence of the welding thermal deformation on the precision and reliability of the bearing, is a technical problem that needs to be solved as soon as possible in the field. SUMMARY

[0006] In order to solve the technical problems of the existing foil thrust bearing, such as easy plastic deformation of the wave foil, reduction of the manufacturing precision of the wave foil, high manufacturing cost of the foil thrust bearing, and influence of the welding thermal deformation on the precision and reliability of the bearing, a new type of laminated foil thrust bearing is provided. The bearing does not need a die and a wave foil, and does not need to use a welding process to connect each foil part. The laminated beam support structure is used to realize the load bearing of the foil thrust bearing, so as to avoid plastic deformation of the wave foil, reduce the processing procedure of the foils, improve the processing precision of the foils, and thereby improve the reliability of the foil thrust bearing.

[0007] To solve the technical problem, the present application provides a new type of laminated foil thrust bearing, characterized in that it comprises a top foil with a plurality of annularly arranged working surfaces, a plurality of annularly mounted support frames, a flat plate and a bottom support plate which are sequentially laminated; the top foil outer ring of the top foil is connected with the flat plate outer ring of the flat plate, the support frames make each working surface of the top foil form a same direction inclined surface in the circumferential direction, and the bottom support plate makes the support surface of the flat plate form a simply supported beam support structure in the circumferential direction.

[0008] The bearing removes the traditional wave foil parts, and forms a beam support structure through the lamination of multiple foil layers. When the top foil outer ring of the top foil is connected to the plate outer ring of the plate, the support frame supported between the top foil and the plate makes each working surface of the top foil form a plurality of same-direction inclined surfaces arranged in a spaced manner in the circumferential direction, so as to form a plurality of wedge-shaped space structures in the circumferential direction together with the rotor carrier plate. When the rotor works and rotates to a certain speed, a dynamic pressure gas film is formed between the rotor carrier plate and the bearing, so as to separate the rotor carrier plate from the bearing, thereby playing a bearing lubrication role. Since there is a gap between the circumferential directions of each working surface of the top foil, the discharge of the dynamic pressure gas in the gap between the rotor carrier plate and the bearing and the suction of the next wedge-shaped space are improved, so that the foil thrust bearing has a better dynamic pressure effect.

[0009] Preferably, the top foil comprises a top foil outer ring, and a plurality of working surfaces connected to the inner circle of the top foil outer ring through the inner circle connecting support; the working surfaces are arranged in a fan shape, and the middle is a shaft hole for the rotor; a radial edge of the working surface on one side of the rotor rotation direction is a working surface starting position, and a radial edge of the working surface on the other side is a working surface ending position.

[0010] The top foil outer ring is connected to the working surface through the connecting support, so that the plurality of working surfaces can be machined from one foil, reducing the machining process and easily ensuring the machining precision. The radial edge of the working surface on one side of the rotor rotation direction is set as the working surface starting position, so that each working surface starting position can be inclined downward and close to the support surface of the plate, so as to form the same direction inclined surface in the circumferential direction and form the same direction wedge-shaped space structure with the rotor carrier plate. The annular working surface is arranged in a plurality of spaced fan-shaped pieces, so that a certain gap is maintained between the circumferential directions of adjacent working surfaces. Such an arrangement effectively improves the entry and discharge of gas between the rotor carrier plate and the bearing, is beneficial to the establishment of the dynamic pressure gas film, and makes the foil thrust bearing have a better dynamic pressure effect.

[0011] Preferably, the support frame comprises a connecting beam, a middle support beam connected to one end of the connecting beam, and an end support beam connected to the other end of the connecting beam; the middle support beam and the end support beam both extend to one side of the connecting beam, so that the support frame has a U-shaped structure; the connecting beam is provided with a support frame connecting hole; the number of the support frames corresponds to the number of the working surfaces of the top foil; the middle support beam supports the middle part of the circumferential direction of the working surface, and the end support beam supports the working surface ending position of the working surface.

[0012] The support frame is close to the bottom of the top foil, and the middle support beam supports the top foil as a fulcrum at the middle part of the working surface of the top foil, and lifts the working surface. When the outer circle of the top foil is fixedly connected with the outer circle of the flat plate, the inclined working surface required by the bearing work is quickly formed to form a wedge structure with the rotor bearing disc. The end support beam is located at the end of the working surface, and supports the end of the working surface during work to avoid deformation of the tail end of the working surface under the high-pressure gas film. In addition, the number of U-shaped support frames can be repeatedly prepared according to the need using a set of molds, and the equipment investment is small.

[0013] Preferably, the flat plate comprises a flat plate outer circle, an annular support surface connected to the inner circle of the flat plate outer circle through a connecting beam, and a flat plate support frame connecting piece corresponding to the support frame on the inner circle of the flat plate outer circle.

[0014] The outer circle of the flat plate is close to the outer circle of the top foil and is connected and fixed by a pin or a screw. The annular support surface of the flat plate is located below the working surface arranged in a ring shape on the top foil, and the support frame is arranged between the top foil and the flat plate. The connecting beam of the support frame is outwardly directed, and the middle support beam and the end support beam are radially inwardly directed. The outer edge of the connecting beam has a radial dimension smaller than the inner diameter dimension of the outer circle of the top foil and the outer circle of the flat plate. Therefore, the support frame does not affect the overlapping connection of the outer circle of the top foil and the outer circle of the flat plate, and the connecting beam of the support frame is connected to the connecting hole on the flat plate support frame connecting piece by a pin or a screw. The directly supported top foil and support frame are arranged on the flat plate. When the front support beam and the rear support beam of the bottom support plate below the flat plate give the flat plate a large-span support, the flat plate has good elasticity and can reduce the overall rigidity of the bearing, increase the bearing damping, and improve the stability of the bearing.

[0015] Preferably, the bottom support plate comprises a bottom support plate outer circle, a bottom support beam connected to the inner circle of the bottom support plate outer circle and arranged in a radial direction, and the bottom support beam is composed of a front support beam and a rear support beam, and the number of the bottom support beam corresponds to the number of the working surface of the top foil. The front support beam is located at the starting position of the working surface of the top foil, and the rear support beam is located at the end position of the working surface of the top foil, so that the annular support surface of the flat plate forms a simply supported beam support structure in a circumferential direction. The inner circle of the bottom support plate outer circle is further provided with a support frame connecting piece corresponding to the support frame.

[0016] The bottom support plate is close to the lower side of the flat plate, and the front support beam and the rear support beam arranged radially on the bottom support plate support the annular support surface of the flat plate, thereby forming a simple beam support structure along the circumference of the annular support surface. The simple beam support structure with the increased span makes the rigidity of the bearing overall lower than that of the traditional wave foil bearing, allows greater elastic deformation to occur, and avoids plastic deformation from occurring, so that the damping capacity of the bearing is stronger, and the stability of the bearing operation is better. The connecting beam of the support frame is connected to the connecting holes on the flat plate support frame connecting piece of the flat plate and the connecting holes on the support frame connecting piece of the bottom support plate through a pin or a screw.

[0017] Preferably, the top foil outer ring, the flat plate outer ring and the bottom support plate outer ring are each provided with a rotor rotation direction mark and a positioning and fixing hole for connection.

[0018] The rotor rotation direction mark marked on the outer ring of the top foil, the flat plate and the bottom support plate facilitates correct installation of the bearing and the rotor. The positioning and fixing hole facilitates accurate positioning and installation of the top foil, the flat plate and the bottom support plate through a pin or a screw, and connection and fixation of the top foil, the flat plate and the bottom support plate into a complete bearing.

[0019] Preferably, the working surface of the top foil is 4-20 pieces. The working surface of the top foil serves as the direct bearing surface of the bearing, and a proper number of working surfaces can be selected to bear the load according to bearings of different diameters.

[0020] Preferably, the connecting beam of the support frame is provided with two support frame connecting holes in the transverse direction; and the connecting holes on the flat plate support frame connecting piece of the flat plate and the connecting holes on the support frame connecting piece of the bottom support plate are both two. The support frame connecting hole is at least one, and the two connecting holes are arranged in the transverse direction to prevent the support frame from being connected in a wrong position and affecting the support effect. According to the size of the bearing, multiple support frame connecting holes can be arranged.

[0021] Preferably, the connecting support connecting the working surface in the top foil is 1-4, and the connecting support is inclined to connect the top foil outer ring and the working surface.

[0022] The top foil outer ring and the working surface in the top foil are connected into a whole through the connecting support, which can make multiple working surfaces be machined from one foil piece, reduce the machining process, and easily ensure the machining precision. On the other hand, a proper number of connecting supports can be selected according to bearings of different diameters, such as double connecting supports. In the working process, the working surface of the top foil is subjected to a tangential force in the rotation direction of the rotor, and then a circumferential tangential force acts on the connecting support. If a vertical connecting support is used, it is easy to deform under the action of the tangential force. Therefore, the connecting support is arranged in an inclined state, which is not easy to deform.

[0023] Preferably, the connecting beams in the plate are multiple, and the connecting beams are inclined to connect the outer ring of the plate with the outer circle of the annular support surface.

[0024] The plate outer ring and the annular support surface are connected by the connecting beams, which can be processed by one foil, reduces the processing procedures, and easily ensures the processing precision. Since the annular support surface is not easy to deform, and the plate is not directly loaded by the working surface, the tangential force is small, so a single connecting beam is generally used. According to the size of the bearing, multiple connecting beams can also be used. On the other hand, the connecting beams are inclined to connect the annular support surface, which can reduce the connecting stiffness of the annular support surface, resist the tangential force of the rotating inner disc, and is beneficial to improve the damping of the bearing support and improve the stability of the bearing.

[0025] The new laminated foil thrust bearing provided by the application cancels the traditional wave foil part, forms a beam support structure by laminating multiple foils, and forms a piece by piece inclined surface in the same direction in the circumferential direction of each working surface of the top foil, so as to cooperate with the rotor load disc to form a wedge structure. When the speed of the rotor is continuously improved, the surrounding gas is continuously dragged into the wedge-shaped space formed between the rotor load disc and the bearing, so as to form a dynamic pressure gas film between the rotor and the bearing, thereby isolating the rotor load disc from the bearing, playing a load lubrication role, effectively reducing the friction and wear between the rotor and the bearing, prolonging the service life, and reducing the power consumption. Since there is a gap between the circumferential direction of each working surface of the top foil, the discharge of the dynamic pressure gas in the gap between the rotor load disc and the bearing and the gas suction of the next wedge-shaped space are improved, so that the foil thrust bearing has better dynamic pressure effect. The bottom support plate arranged on the bottom surface of the bearing supports the annular support surface of the plate above it by the radially arranged bottom support beams, and forms a simply supported beam support structure in the circumferential direction. This simply supported beam support structure with increased span makes the overall stiffness of the bearing lower than that of the traditional wave foil bearing, allows greater elastic deformation, and avoids plastic deformation, so that the damping capacity of the bearing is stronger, and the stability of the bearing operation is better. Since there is no wave foil part in the bearing, no precise mold processing is required, the processing cost of the foil thrust bearing is reduced, and the long-term consistency of the bearing precision is improved. In addition, the parts of the bearing are fixed by connecting means such as pins, which avoids the welding process and avoids the influence of welding thermal deformation on the precision and reliability of the bearing. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a sectional view of the first existing foil thrust bearing;

[0027] Figure 2 is a sectional view of the second existing foil thrust bearing;

[0028] Figure 3The exploded view of the new type of laminated foil thrust bearing embodiment of the present application;

[0029] Figure 4 The front view of the new type of laminated foil thrust bearing embodiment of the present application;

[0030] Figure 5 The bearing shown in Figure 4 The front projection view of the bearing shown in

[0031] Figure 6 The cross-sectional view of the bearing shown in Figure 4 The part view of the top foil shown in

[0032] Figure 7 The structure schematic view of the top foil of the bearing in free state and working force state;

[0033] Figure 8 The part view of the top foil shown in Figure 3

[0034] The part view of the support frame shown in Figure 9 Figure 3 The part view of the flat plate shown in

[0035] Figure 10 Figure 3 The part view of the bottom support plate shown in

[0036] Figure 11 The part view of the bottom support plate shown in Figure 3

[0037] Figures 3-11 1-top foil, 101-top foil outer ring, 102-connection support, 103-working surface, 1032-starting position of working surface, 1033-end position of working surface, 104-rotor rotation direction mark, 105-positioning and fixing hole;

[0038] 2-support frame, 201-connection crossbeam, 202-middle support beam, 203-end support beam, 204-support frame connection hole;

[0039] 3-flat plate, 301-flat plate outer ring, 302-connection beam, 303-annular support surface, 304-flat plate support frame connecting piece;

[0040] 4-bottom support plate, 401-bottom support plate outer ring, 402-front support beam, 403-rear support beam, 404-support frame connecting piece. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be described in detail below in combination with the drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the present application and do not constitute limitation to the present application.​​​

[0042] As Figure 3 , Figure 4 and Figure 5 shown, the present application provides a new type of laminated foil thrust bearing embodiment, which includes the top foil 1, support frame 2, flat plate 3 and bottom support plate 4 stacked in turn, and the support frame 2 is installed in a plurality of annular intervals. In this embodiment, the top foil 1, flat plate 3 and bottom support plate 4 are all circular, and the support frame 2 is U-shaped. The inner ring of the top foil 1 is an annular working surface, which can be surrounded by a plurality of working surfaces 103. By overlapping and connecting the top foil outer ring 101 of the top foil with the flat plate outer ring 301 of the flat plate, the support of the support frame 2 causes the working surfaces 103 of the top foil above it to form a circumferential inclined surface in the same direction, and the bottom support plate 4 causes the support surface of the flat plate 3 above it to form a simply supported beam support structure in the circumferential direction. The bearing provided by the present application eliminates the traditional wave foil parts, and forms a beam support structure by stacking multiple foils. When the top foil outer ring 101 and the flat plate outer ring 301 are overlapped and connected, the support frame 2 supported between the top foil 1 and the flat plate 3 causes the working surfaces 103 of the top foil to form a piece of inclined surface in the same direction arranged in intervals in the circumferential direction, so as to cooperate with the rotor bearing disc to form a wedge-shaped space structure in the circumferential direction. When the rotor works and rotates to a certain speed, a dynamic pressure gas film is formed between the rotor bearing disc and the bearing, which separates the rotor bearing disc from the bearing, thereby playing a role in bearing lubrication. Due to the existence of intervals between the working surfaces 103 of the top foil 1 in the circumferential direction, the discharge of dynamic pressure gas in the gap between the rotor bearing disc and the bearing and the suction of the next wedge-shaped space can be improved, so that the foil thrust bearing has better dynamic pressure effect.

[0043] As Figure 4 , Figure 5 and Figure 8 shown, the top foil 1 in this embodiment includes a top foil outer ring 101, a plurality of working surfaces 103 connected to the inner circle of the top foil outer ring 101 through a connecting bracket 102. The working surface 103 is arranged in a ring shape with a fan, and the middle is the shaft hole of the rotor. The surface of the top foil outer ring 101 is provided with a bearing rotation direction mark 104 and a positioning and fixing hole 105 for connection. The radial edge of the working surface 103 on the side facing the rotor rotation direction is positioned as the working surface starting position 1032, and the radial edge on the other side of the working surface 103 is the working surface end position 1033. Since the top foil outer ring 101 connects the working surface 103 through the connecting bracket 102, a plurality of working surfaces can be machined from one foil, thereby reducing the machining process and easily ensuring the machining precision. Please refer to Figure 6 , Figure 7The radial edge of the working surface 103 is first set as the working surface starting position 1032 in the direction of rotation of the rotor. When the top foil outer ring 101 is connected to the flat outer ring 301, the working surface starting position 1032 of each working surface is inclined downward and close to the support surface of the flat surface 3, so as to form inclined surfaces in the same direction along the circumference. When the top foil 1 is installed on the rotor bearing disc, a wedge-shaped space structure in the same direction is formed. The high-speed rotation of the rotor causes the gas flow between the working surface 103 and the rotor bearing disc to generate a supporting dynamic pressure gas film. The annularly arranged working surface 103 is arranged as a plurality of spaced fan-shaped pieces, so that a gap is maintained between the circumferences of adjacent working surfaces 103. This arrangement effectively improves the entry and discharge of gas between the rotor bearing disc and the bearing, and is conducive to the establishment of a dynamic pressure gas film, so that the foil thrust bearing has better dynamic pressure effect.

[0044] As shown in Figure 8 , the inner ring of the top foil 1 is surrounded by eight working surfaces 103. The number of working surfaces can be set to 4-20 according to needs. The working surface 103 of the top foil serves as the bearing surface, which facilitates the selection of a proper number of working surfaces 103 to bear the load according to bearings of different diameters. In this embodiment, the connecting bracket 102 connecting the working surface 103 of the top foil outer ring 101 is a double connecting bracket. According to the size of the bearing diameter and the size of the working surface 103, the number of connecting brackets 102 can be 1-4. The inner circle of the top foil outer ring 101 is connected to the outer edge of the working surface 103 through the inclined connecting bracket 102. Since the working surface 103 of the top foil is subjected to tangential force in the direction of rotation of the rotor during operation, the connecting bracket 102 is subjected to tangential force in the circumferential direction. If a vertical connecting bracket is used, it is easy to deform under the action of tangential force. Therefore, the connecting bracket 102 is arranged in an inclined state, which is not easy to deform, so as to make the bearing have better elasticity.

[0045] As shown in Figure 4 , Figure 5 , Figure 6 and Figure 9As shown, the support frame 2 in the embodiment comprises a connecting beam 201, a middle support beam 202 connected to one end of the connecting beam 201, and an end support beam 203 connected to the other end of the connecting beam 201. The middle support beam 202 and the end support beam 203 both extend to one side of the connecting beam, so that the support frame 2 has a U-shaped structure. The connecting beam 201 is further provided with a support frame connecting hole 204. The number of the support frames 2 corresponds to the number of the working surfaces 103 of the top foil, i.e., eight support frames 2 in the embodiment. The middle support beam 202 is supported at the middle of the circumferential direction of the working surface 103 of the top foil, and the end support beam 203 is supported at the working surface end 1033 of the working surface 103. Since the support frame 2 is closely attached to the bottom of the top foil 1, and the middle support beam 202 is supported at the middle of the circumferential direction of the working surface 103 of the top foil as a fulcrum, the working surface 103 is lifted. After the outer ring 101 of the top foil is overlapped and connected with the flat plate outer ring 301, the working surface 103 of the top foil is quickly formed into an inclined surface required by the bearing work, so as to form a wedge-shaped structure with the thrust disc of the rotor. The end support beam 203 corresponds to the working surface end 1033 of the working surface 103, and as shown, the end support beam 203 supports the end of the working surface 103 during work, avoiding the deformation of the end of the working surface caused by the high-pressure gas film. In addition, the U-shaped support frame 2 can be repeatedly prepared according to the number of molds required, and the equipment investment is small. Figure 7

[0046] As shown, the support frame 2 in the embodiment comprises a connecting beam 201, a middle support beam 202 connected to one end of the connecting beam 201, and an end support beam 203 connected to the other end of the connecting beam 201. The middle support beam 202 and the end support beam 203 both extend to one side of the connecting beam, so that the support frame 2 has a U-shaped structure. The connecting beam 201 is further provided with a support frame connecting hole 204. The number of the support frames 2 corresponds to the number of the working surfaces 103 of the top foil, i.e., eight support frames 2 in the embodiment. The middle support beam 202 is supported at the middle of the circumferential direction of the working surface 103 of the top foil, and the end support beam 203 is supported at the working surface end 1033 of the working surface 103. Since the support frame 2 is closely attached to the bottom of the top foil 1, and the middle support beam 202 is supported at the middle of the circumferential direction of the working surface 103 of the top foil as a fulcrum, the working surface 103 is lifted. After the outer ring 101 of the top foil is overlapped and connected with the flat plate outer ring 301, the working surface 103 of the top foil is quickly formed into an inclined surface required by the bearing work, so as to form a wedge-shaped structure with the thrust disc of the rotor. The end support beam 203 corresponds to the working surface end 1033 of the working surface 103, and as shown, the end support beam 203 supports the end of the working surface 103 during work, avoiding the deformation of the end of the working surface caused by the high-pressure gas film. In addition, the U-shaped support frame 2 can be repeatedly prepared according to the number of molds required, and the equipment investment is small. Figure 5 , Figure 6 and Figure 10 ​As shown, the flat plate 3 comprises a flat plate outer ring 301, an annular support surface 303 connected to the inner circle of the flat plate outer ring 301 through a connecting beam 302, and the inner circle of the flat plate outer ring 301 is also provided with a flat plate support frame connecting piece 304 corresponding to the support frame 2, and the flat plate support frame connecting piece is provided with a support frame connecting hole corresponding thereto. The flat plate outer ring 301 is fixedly connected through a pin or a screw to the top foil outer ring 101, and the annular support surface 303 of the flat plate is located below the annular working surface 103 of the top foil 1, and the support frame 2 is annularly and spacedly arranged between the top foil 1 and the flat plate 3. The connecting beam 201 of the support frame is outwardly directed to the circumference, and the intermediate support beam 202 and the end support beam 203 are radially inwardly directed. The outer edge of the connecting beam 201 has a radial dimension smaller than the inner diameter dimension of the top foil outer ring 101 and the flat plate outer ring 301, so that the support frame 2 does not affect the overlapping connection of the top foil outer ring and the flat plate outer ring, and the connecting beam 201 of the support frame is connected to the connecting hole on the flat plate support frame connecting piece 304 through a pin or a screw. The directly loaded top foil 1 and the support frame 2 are arranged on the flat plate 3, and when the front support beam and the rear support beam of the bottom support plate 4 below the flat plate 3 give a large-span support to the flat plate 3, the flat plate 3 has good elasticity to reduce the overall rigidity of the bearing, increase the bearing damping, and improve the stability of the bearing. The connecting beams 302 in the flat plate 3 are annularly arranged in multiple numbers, and the connecting beams 302 are inclined to integrally connect the flat plate outer ring 301 and the outer circumference of the annular support surface 303. The connecting beams 302 integrally connect the flat plate outer ring 301 and the annular support surface, which can be processed from one foil sheet, thereby reducing the processing procedures and easily ensuring the processing precision. Since the annular support surface 303 is not easy to deform in structure, and the flat plate is not a directly loaded working surface, the tangential force received is not large, and therefore a single connecting beam is generally used. According to the size of the bearing, a multiple connecting beam structure can also be used. On the other hand, the inclined connecting beams are connected to the annular support surface, which can reduce the connecting rigidity of the annular support surface 303, resist the tangential force of the internal disc during rotation, and is beneficial to improve the damping of the bearing support and improve the stability of the bearing.

[0047] As shown in Figure 5 , Figure 6 and Figure 11 , the bottom support plate 4 comprises a bottom support plate outer ring 401, a bottom support beam connected to the inner circle of the bottom support plate outer ring 401 and arranged in a radial direction, and the bottom support beam is composed of a front support beam 402 and a rear support beam 403. The number of the bottom support beam corresponds to the number of the working surface 103 of the top foil 1, that is, the number of the bottom support beam in the embodiment is also eight pairs. The front support beam 402 is located at the starting position 1032 of the working surface of the top foil 1, and the rear support beam 403 is located at the end position 1033 of the working surface, so that the annular support surface 303 of the flat plate forms a simply supported beam support structure in a circumferential direction (see Figure 6The inner circle of the bottom support plate outer circle 401 is also provided with support frame connecting pieces 404 corresponding to the connection of the support frame 2.

[0048] Since the bottom support plate 4 is tightly attached to the lower surface of the flat plate 3, the front support beam 402 and the rear support beam 403 arranged radially by the bottom support plate 4 support the annular support surface 303 of the flat plate, forming a simple beam support structure in sections along the circumference of the annular support surface 303. This simple beam support structure with increased span makes the stiffness of the bearing overall lower than that of the traditional wave foil bearing, allowing greater elastic deformation to occur, avoiding plastic deformation of the foil, so that the damping capacity of the bearing is stronger and the stability of the bearing operation is better.

[0049] As shown in Figure 9 , the connecting beam 201 of the support frame 2 is provided with two support frame connecting holes 204 transversely. The connecting holes on the flat plate support frame connecting piece 304 of the flat plate and the connecting holes on the support frame connecting piece 404 of the bottom support plate are also two. The support frame connecting hole 204 is at least one, and the two connecting holes are arranged transversely to avoid misconnection of the support frame 2, affecting the support effect. According to the size of the bearing, multiple support frame connecting holes can be arranged. The connecting beam 201 of the support frame is connected to the connecting holes on the flat plate support frame connecting piece 304 of the flat plate and the connecting holes on the support frame connecting piece 404 of the bottom support plate through pins or screws, and the support frame 2, the flat plate 3 and the bottom support plate 4 are connected into one body.

[0050] As shown in Figures 8-11 , the top foil outer circle 101 of the top foil, the flat plate outer circle 103 of the flat plate and the bottom support plate outer circle 401 of the bottom support plate are all marked with a rotor rotation direction mark and a positioning and fixing hole for connection, which facilitates correct installation of the bearing and the rotor. The rotor rotation direction marks of each foil are stacked in the same direction, and the positioning and fixing holes of each foil are correspondingly centered, and the top foil 1, the flat plate 3 and the bottom support plate 4 are accurately positioned and installed through pins or screws, and are connected into a complete bearing.

[0051] As shown in Figure 6 , Figure 7As shown, the cross-sectional structure of the working surface of the new laminated foil thrust bearing of the present application, when the top foil outer ring 101 of the top foil and the plate outer ring 301 of the plate are overlapped and fixed, a pair of support beams of the support frame 2, i.e. the middle support beam 202 and the end support beam 203, are supported between the top foil 1 and the plate 3, facilitating the formation of an inclined working surface 103 on the surface of the top foil 1 to ensure good operation of the bearing. The top foil 1, the support frame 2 and the plate 3 are placed above the bottom support plate 4. Due to the support of the front support beam 402 and the rear support beam 403 of the bottom support plate 4 on the annular support surface 303 of the plate, a larger span of the annular support surface 303 is formed, which can reduce the overall rigidity of the bearing and improve the damping of the bearing. When subjected to dynamic pressure gas film vibration, the deformation of each support structure can be used to absorb the vibration energy of the gas film, thereby suppressing the vibration of the gas film and improving the stability of the bearing. The bearing structure cancels the elastic wave foil of the ordinary foil thrust bearing, does not need to use a precision mold for processing, improves the processing economy and long-term consistency of the precision of the foil bearing, and ensures the reliability of the foil thrust bearing. In addition, the foil parts of the bearing of the present application are connected and fixed by pin, screw and other connection methods, eliminating the welding process, thereby avoiding the influence of welding thermal deformation on the precision and reliability of the bearing.

[0052] Techniques, methods, and equipment known to those of ordinary skill in the relevant art should be considered within the scope of the present specification. Any specific values in the present specification should be interpreted as merely illustrative and not limiting to the present invention.

[0053] The above description is only a specific implementation of the present application. It should be noted that any modification, equivalent replacement and change made within the spirit and framework of the present application should be included in the protection scope of the present application.

Claims

1. A novel stacked foil thrust bearing, characterized in that, It includes a top foil with multiple annular working surfaces stacked in sequence, multiple circumferentially mounted support frames, a flat plate, and a bottom support plate; the outer ring of the top foil overlaps and connects with the outer ring of the flat plate, the support frames cause each working surface of the top foil to form an inclined surface in the same direction along the circumference, and the bottom support plate causes the support surface of the flat plate to form a simply supported beam support structure along the circumference.

2. The novel stacked foil thrust bearing as described in claim 1, characterized in that, The top foil includes an outer ring of the top foil and multiple working surfaces connected to the inner circle of the outer ring of the top foil via a connecting bracket; the working surface is arranged in a fan-shaped ring with a rotor shaft hole in the middle; the radial edge on the working surface facing the direction of rotor rotation is the starting position of the working surface, and the radial edge on the other side of the working surface is the ending position of the working surface.

3. The novel stacked foil thrust bearing as described in claim 1, characterized in that, The support frame includes a connecting beam, an intermediate support beam connected to one end of the connecting beam, and an end support beam connected to the other end of the connecting beam. Both the intermediate support beam and the end support beam extend to one side of the connecting beam, making the support frame a U-shaped structure. The connecting beam is provided with support frame connection holes. The number of support frames corresponds to the number of working surfaces of the top foil. The intermediate support beam supports the middle part of the circumference of the working surface, and the end support beam supports the end of the working surface.

4. The novel stacked foil thrust bearing as described in claim 1, characterized in that, The plate includes an outer ring and an annular support surface connected to the inner circle of the outer ring via a connecting beam. The inner circle of the outer ring is also provided with a plate support frame connecting piece corresponding to the support frame.

5. The novel stacked foil thrust bearing as described in claim 1, characterized in that, The bottom support plate includes an outer ring and a bottom support beam connected to the inner circle of the outer ring and arranged radially. The bottom support beam consists of a front support beam and a rear support beam. The number of bottom support beams corresponds to the number of working surfaces of the top foil. The front support beam is located at the beginning of the working surface of the top foil, and the rear support beam is located at the end of the working surface of the top foil, so that the annular support surface of the flat plate forms a series of simply supported beam support structures along the circumference. The inner circle of the outer ring of the bottom support plate is also provided with a support frame connecting piece corresponding to the support frame.

6. The novel stacked foil thrust bearing as described in claim 2, characterized in that, The outer ring of the top foil, the outer ring of the flat plate, and the outer ring of the bottom support plate are all provided with rotor rotation direction markings and positioning and fixing holes for connection.

7. The novel stacked foil thrust bearing as described in claim 1, characterized in that, The working surface of the top foil is 4 to 20 pieces.

8. The novel stacked foil thrust bearing as described in claim 3, characterized in that, The connecting beam of the support frame has two support frame connecting holes in the transverse direction; the corresponding connecting holes on the flat plate support frame connecting piece and the bottom support plate support frame connecting piece are both two.

9. The novel stacked foil thrust bearing as described in claim 1, characterized in that, The top foil has 1 to 4 connecting brackets that connect to the working surface, and the connecting brackets are inclined to connect the outer ring of the top foil to the outer edge of the working surface.

10. The novel stacked foil thrust bearing as described in claim 4, characterized in that, The plate has multiple connecting beams that connect the outer ring of the plate to the outer periphery of the annular support surface at an incline.

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