Segmented bearing gas thrust bearing with metal rubber damping element

Abstract

This invention discloses a segmented support type gas thrust bearing with metal rubber damping elements, belonging to the field of gas bearing technology. The bearing comprises, along its axial direction, a thrust disc, a top layer foil, a gasket, 36 metal rubber cylinders, and a base. The base has cylindrical grooves on its end face corresponding to the metal rubber cylinders, with each cylinder embedded in one groove and its upper end abutting against a gasket. A top layer foil is laid on top of the gasket, and the top layer foil, gasket, and base are bolted together via bolt holes. The thrust disc is mounted on a rotating shaft and rotates relative to the top layer foil. The end face of the thrust disc is machined with a dendritic microtexture, and the end face of the base is machined with an annular boss. The microtexture depth is 0.2 mm, and the annular boss height is 2.5 mm. This invention combines the distributed elastic support of the metal rubber cylinders, the pumping load-increasing effect of the dendritic texture, and the dynamic pressure effect of the annular boss on the base, which can significantly improve the bearing's stiffness and damping characteristics, enhance the gas film load-bearing capacity, and suppress gas film instability. This bearing features convenient bolt connection for easy assembly and disassembly, simple structure, and good impact resistance. It is suitable for high-speed, high-temperature, and variable operating conditions, and can effectively extend the service life of the bearing.

Description

Technical Field

[0001] This invention relates to the field of gas thrust bearing technology, and in particular to a gas thrust bearing that combines segmented support with metal rubber damping elements and a dendritic microtexture. Background Technology

[0002] Gas thrust bearings use air as the lubricating medium and have outstanding advantages such as oil-free lubrication, resistance to high and low temperatures, strong adaptability to high speed, low frictional power consumption, and long service life. They are the core axial support components of high-speed rotating equipment such as micro turbine expanders, high-speed centrifugal air compressors, aviation environmental control systems, and vehicle-mounted power turbines.

[0003] Existing mature gas foil thrust bearings generally employ a double-layer fan-shaped segmented structure consisting of a top foil and a corrugated foil. Axial load is achieved by a dynamic pressure gas film formed between the top foil and the thrust disk, driven by a rotating thrust disc. The corrugated foil provides elastic support and structural damping. However, this structure still suffers from the following technical defects: mismatch between the radial stiffness distribution of the corrugated foil and the gas film load distribution, resulting in uneven gas film pressure distribution; dry friction easily occurs during start-up and shutdown, causing foil wear; gas film vortex oscillation is easily induced under high-speed conditions; and the corrugated foil structure has limited damping and insufficient impact resistance. Although recent research has used metal rubber as an elastic support material or processed microtextures on the bearing surface to enhance the dynamic pressure effect, existing structures generally suffer from problems such as unreasonable matching of support stiffness and damping, difficulties in positioning and assembling metal rubber units, and underutilization of the pumping load-increasing potential of the rotating thrust disc surface texture, limiting their engineering applications. Summary of the Invention

[0004] To address the aforementioned technical deficiencies of existing gas foil thrust bearings, this invention provides a segmented support gas thrust bearing with metal-rubber damping elements. While retaining the traditional top-layer foil structure, this invention employs metal-rubber damping elements as distributed elastic support units. An annular boss is machined on the base end face, and a dendritic microtexture is machined on the rotating thrust disc end face. This effectively improves the bearing's axial load-bearing capacity, high-speed operation stability, start-stop wear resistance, and impact resistance, meeting the application requirements of high-end high-speed power equipment such as micro-turbine expanders, high-speed centrifugal air compressors, and aerospace environmental control systems.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0006] A segmented support gas thrust bearing with metal-rubber damping elements includes a thrust disc, a top layer foil, a gasket, multiple metal-rubber cylinders, and a base. The thrust disc has a dendritic microtexture on its end face facing the top layer foil. The base has cylindrical grooves corresponding to the metal-rubber cylinders on its end face, with the metal-rubber cylinders embedded in the corresponding cylindrical grooves and their upper ends abutting against the gaskets. The top layer foil is laid on top of the gaskets, and a dynamic pressure gas film gap is formed between the top layer foil and the thrust disc. An annular boss is machined on the end face of the base.

[0007] The metal-rubber cylinder is woven and pressed from stainless steel wire, and has a network of 36 interconnected pores evenly distributed along the circumference of the base on the same pitch circle, forming a distributed elastic support layer. The Coulomb damping generated by the contact friction between the metal wires inside the metal-rubber cylinder is significantly better than that of the traditional corrugated foil structure, which can greatly improve the overall structural damping of the bearing and suppress air film vortex oscillation.

[0008] The inner diameter of the cylindrical groove and the outer diameter of the metal rubber cylinder are in clearance fit with a clearance of 0.1mm, which achieves precise positioning and constraint of the metal rubber cylinder while retaining elastic deformation allowance; the depth of the cylindrical groove is less than the height of the metal rubber cylinder, ensuring that the upper end of the metal rubber cylinder reliably abuts against the gasket.

[0009] The dendritic microtexture includes multiple fan-shaped textured areas evenly distributed circumferentially along the thrust disc end face. Each fan-shaped textured area has radially arranged dendritic branching grooves, which branch out progressively from the inside out, with 2 to 4 branching levels and a depth of 0.2 mm. When the thrust disc rotates at high speed with the shaft, the dendritic branching grooves generate a significant dynamic pressure effect, transporting gas from the outer edge to the high-pressure area of ​​the gas film, enhancing the dynamic pressure effect of the gas film, and improving the bearing's load-bearing capacity. At the same time, the branching grooves increase the gas flow area, which is beneficial for uniform gas film distribution and heat dissipation.

[0010] The annular bosses on the end face of the base are distributed in a circular array between adjacent cylindrical grooves, with a height of 2.5 mm and an area coverage of 10% to 20%. When the bearing is in operation, the annular bosses act as secondary supports when the metal rubber is compressed and deformed, significantly improving the bearing's load-bearing characteristics, stiffness, and damping.

[0011] This invention combines the distributed elastic support of metal rubber cylinders, the pumping and load-increasing effect of the dendritic textured thrust plate, and the annular boss of the base, which can significantly improve the stiffness and damping characteristics of the bearing, suppress foil vibration and gas film instability, and the synergistic effect of the multi-layer texture is conducive to greatly improving the bearing's load-bearing capacity and operational stability.

[0012] The elastic contact between the metal rubber cylinder and the gasket can buffer axial impact and micro-vibration during start-up, shutdown, and light-load conditions, avoiding the problem of rigid friction between the thrust plate and the top foil during start-up and shutdown. Under high-speed and heavy-load conditions, the metal rubber cylinder and the gasket deform together, significantly improving the overall support stiffness, effectively resisting air film disturbance and axial movement, and dissipating vibration energy.

[0013] As a preferred embodiment, the top layer foil is a flat or corrugated foil made of high-temperature resistant metal sheet with a thickness controlled between 0.1 and 0.2 mm. Bolt holes are correspondingly provided on the top layer foil and the gasket. The top layer foil, gasket, and base are fixedly connected by bolts passing through the bolt holes, ensuring convenient assembly and disassembly and reliable connection. The low coefficient of thermal expansion material, combined with the elastic support of metal and rubber, can adaptively compensate for the thermal expansion deformation of the foil under high-temperature conditions, improving the reliability of the bearing during high-temperature operation.

[0014] This invention has a simple structure, is easy to assemble, and has good impact resistance. It can be manufactured using traditional machining, pressing and forming and laser processing techniques. It has excellent mass production processability and can be widely used in oil-free axial support applications such as high-speed turbine machinery, aviation environmental control equipment, and high-speed blowers. Attached Figure Description

[0015] Figure 1 This is an exploded view of the segmented support gas thrust bearing with metal rubber damping element of the present invention;

[0016] Figure 2 This is an assembly perspective view of the segmented support gas thrust bearing with metal rubber damping element of the present invention;

[0017] Figure 3 This is an end view of the thrust plate of the present invention;

[0018] Figure 4 This is a front view of the base of the present invention;

[0019] Figure 5 This is a schematic diagram showing the distribution of the metal rubber in this invention;

[0020] Figure 6 This is a schematic diagram of the top foil of the present invention. Detailed Implementation

[0021] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. The described embodiments are only preferred embodiments of the present invention and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without departing from the core innovative structure of the present invention and without creative labor fall within the protection scope of the present invention.

[0022] Example 1: Combination Figure 1 and Figure 2 As shown, this embodiment designs a segmented support gas thrust bearing with metal rubber damping elements, including a thrust plate (7), a top layer foil (1), a gasket (2), 36 metal rubber cylinders (3), and a base (4), which are stacked sequentially from bottom to top. The thrust plate (7) is mounted on a rotating shaft and rotates with the shaft. Its end face facing the top layer foil (1) is processed with a dendritic microtexture (8). The end face of the base (4) has 36 cylindrical grooves (5), and the 36 metal rubber cylinders (3) are embedded in the cylindrical grooves (5) one by one. Their upper ends abut against the gasket (2). The top layer foil (1) is laid on top of the gasket (2), and a dynamic pressure gas film gap is formed between the top layer foil (1) and the thrust plate (7).

[0023] The metal-rubber cylinders (3) are woven and pressed from stainless steel wires and have an internal interconnected porous structure. They are evenly distributed on the same pitch circle along the circumference of the base (4), and the height of each metal-rubber cylinder (3) is equal, forming a distributed elastic support layer with uniform stiffness. The contact friction between the metal wires inside the metal-rubber cylinders (3) provides considerable Coulomb damping, which can effectively suppress the air film vortex oscillation under high-speed bearing conditions.

[0024] Combination Figure 4 As shown, the inner diameter of the cylindrical groove (5) and the outer diameter of the metal rubber cylinder (3) are in clearance fit, with a fit clearance of 0.1mm. This ensures accurate assembly and positioning of the metal rubber cylinder (3) and provides space for its elastic deformation under pressure. The depth of the cylindrical groove (5) is less than the height of the metal rubber cylinder (3), ensuring that the upper end of the metal rubber cylinder (3) reliably abuts against the gasket (2) to form an elastic support.

[0025] Combination Figure 3 As shown, the thrust plate (7) has a dendritic microtexture (8) on its end face. The dendritic microtexture (8) includes eight fan-shaped textured areas evenly distributed along the circumference of the thrust plate (7) end face. Each fan-shaped textured area has a radially arranged dendritic branching groove. The groove branches from the inside to the outside in three stages, with a depth of 0.2 mm. When the thrust plate (7) rotates, the dendritic branching groove generates a pumping effect, pumping gas into the high-pressure area of ​​the gas film, enhancing the dynamic pressure bearing capacity. During the start-up and shutdown phases, the gas stored in the groove assists in the rapid establishment of the gas film, avoiding direct contact and friction between the thrust plate (7) and the top foil (1).

[0026] Combination Figure 4 and Figure 5 As shown, an annular boss (6) with a height of 2.5 mm is machined on the end face of the base (4). It is distributed in the area between adjacent cylindrical grooves (5) and is evenly distributed in an annular array. When the bearing is running, the area of ​​the annular boss (6) plays the role of secondary support, further improving the bearing capacity.

[0027] As a preferred embodiment, the top foil (1) is a flat foil or a corrugated foil, made of a high-temperature resistant metal sheet with a thickness controlled between 0.1 and 0.2 mm. Bolt holes are correspondingly provided on the top foil (1) and the gasket (2). The top foil (1), the gasket (2), and the base (4) are fixedly connected by bolts passing through the bolt holes, which makes disassembly and assembly convenient and the connection reliable. The low thermal expansion coefficient material combined with the elastic support of metal rubber can adaptively compensate for the thermal expansion deformation of the foil under high-temperature conditions, thereby improving the reliability of the bearing at high temperatures.

[0028] Assembly process in this embodiment: Combining Figure 1 and Figure 4 As shown, firstly, a dendritic microtexture (8) is processed on the end face of the thrust plate (7) and an annular boss (6) is processed on the end face of the base (4) using laser processing. Then, 36 cylindrical grooves (5) are opened on the end face of the base (4), and 36 metal rubber cylinders (3) are embedded into the corresponding cylindrical grooves (5) one by one. Then, the gasket (2) is placed on the upper end of the 36 metal rubber cylinders (3), so that the upper end of each metal rubber cylinder (3) evenly abuts against the gasket (2). Then, the top foil (1) is laid on the gasket (2), so that the top foil (1), the gasket (2) and the bolt holes on the base (4) are aligned one by one, the bolts are inserted and tightened to ensure tight fit, flatness and no gaps. Finally, the thrust plate (7) is mounted on the rotating shaft, so that the end face with the dendritic microtexture (8) is opposite to the top foil (1), and the overall assembly of the metal rubber damping element segmented support gas thrust bearing is completed.

Claims

1. A segmented support gas thrust bearing with metal-rubber damping elements, characterized in that: The bearing comprises, from top to bottom along the axial direction, a thrust plate (7), a top foil (1), a gasket (2), multiple metal rubber cylinders (3), and a base (4). The thrust plate (7) is mounted on the rotating shaft, and its end face facing the top foil (1) is machined with a dendritic microtexture (8). The end face of the base (4) is provided with cylindrical grooves (5) corresponding to the metal rubber cylinders (3). The metal rubber cylinders (3) are embedded in the corresponding cylindrical grooves (5), and their upper ends abut against the gaskets (2). The top foil (1) is laid on the side of the gasket (2) away from the metal rubber cylinders (3). A dynamic pressure air film gap is formed between the top foil (1) and the thrust plate (7). The end face of the base (4) is machined with an annular boss (6) to provide secondary support for the bearing during operation.

2. The segmented support gas thrust bearing with metal-rubber damping element according to claim 1, characterized in that: The metal rubber cylinder (3) is woven and pressed from stainless steel wire and has a connected pore structure inside. There are 36 metal rubber cylinders (3) and they are evenly distributed on the same pitch circle along the circumference of the base (4). The height of each metal rubber cylinder (3) is equal.

3. The segmented support gas thrust bearing with metal-rubber damping element according to claim 1, characterized in that: The inner diameter of the cylindrical groove (5) and the outer diameter of the metal rubber cylinder (3) are in clearance fit, with a clearance of 0.1 mm; the depth of the cylindrical groove (5) is less than the height of the metal rubber cylinder (3).

4. The segmented support gas thrust bearing with metal-rubber damping element according to claim 1, characterized in that: The dendritic microtexture (8) includes multiple fan-shaped textured areas evenly distributed along the circumferential direction of the thrust plate (7). Each fan-shaped textured area is provided with radially arranged dendritic branching grooves. The grooves branch out from the inside to the outside, with a branching level of 2 to 4. The depth of the dendritic microtexture (8) is 0.2 mm.

5. The segmented support gas thrust bearing with metal-rubber damping element according to claim 1, characterized in that: The annular boss (6) is distributed in the area between adjacent cylindrical grooves (5) on the end face of the base (4) and is evenly distributed in a ring array. The height of the annular boss (6) is 2.5 mm and the area occupancy rate is 10%~20%.

6. The segmented support gas thrust bearing with metal-rubber damping element according to claim 1, characterized in that: The top foil (1) is a flat foil or a corrugated foil, made of a high-temperature resistant metal sheet. Bolt holes are provided on the top foil (1) and the gasket (2) respectively. The top foil (1), the gasket (2) and the base (4) are fixedly connected by bolts passing through the bolt holes.

7. The segmented support gas thrust bearing with metal-rubber damping element according to claim 1 or 6, characterized in that: The bolt holes are evenly distributed along the circumference of the top foil (1) and the gasket (2).

8. The segmented support gas thrust bearing with metal-rubber damping element according to any one of claims 1 to 7, characterized in that: The dendritic microtexture (8) is formed by laser processing.

9. An assembly method for a segmented support type gas thrust bearing with metal-rubber damping elements, characterized in that, The process includes the following steps: (1) Using laser processing, a dendritic micro-texture (8) is processed on the end face of the thrust plate (7), a cylindrical groove (5) is processed on the end face of the base (4), and an annular boss (6) is processed on the surface; (2) 36 cylindrical grooves (5) are opened on the end face of the base (4), and 36 metal rubber cylinders (3) are embedded into the corresponding cylindrical grooves (5) one by one; (3) The gasket (2) is placed on the upper end of the 36 metal rubber cylinders (3), so that the upper end of each metal rubber cylinder (3) abuts against the gasket (2); (4) The top foil (1) is laid on the gasket (2), so that the top foil (1), the gasket (2) and the bolt holes on the base (4) are aligned one by one, and the bolts are inserted and tightened; the thrust plate (7) is aligned with the end face of the dendritic micro-texture (8) and the top foil (1) to complete the assembly.

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