A radial gas foil bearing

Abstract

The present invention provides a radial gas foil bearing, which relates to the technical field of bearings. The bearing comprises a bearing sleeve, a top foil and a bottom foil, and also comprises a foil elastic component. The bearing sleeve, the top foil, the bottom foil and the foil elastic component are all arranged in a cylindrical shape with openings at both ends, and the bearing sleeve, the bottom foil, the foil elastic component and the top foil are sequentially sleeved from the outside to the inside, and the bottom foil, the foil elastic component and the top foil are all detachably connected to the inner wall of the bearing sleeve; the foil elastic component can undergo elastic deformation and rub against each other to increase the damping of the bearing. The present invention overcomes the defects of the air foil bearing in the prior art, which has low damping and poor impact resistance, and limits its application development to a certain extent.

Description

Technical Field

[0001] The invention relates to the technical field of bearings, and in particular to a radial gas foil bearing. Background Art

[0002] The common air foil bearing is a dynamic pressure air bearing with a good flexible surface composed of one or more layers of corrugated foil and top foil. It relies on the relative movement of the shaft and the bearing surface to enable the rotating shaft to suck gas with a certain viscosity into the wedge-shaped space between the shaft and the bearing top foil for extrusion, forming a lubricating gas film with a certain pressure, thereby suspending the rotating shaft.

[0003] Air foil bearing principle Figure 1 and Figure 2 As shown, when there is a wedge-shaped space between two relatively moving surfaces, the surfaces moving against each other continuously drive the gas into the wedge-shaped groove, so that a dynamic pressure gas film 103 with a certain pressure is formed in the wedge-shaped groove, that is, the dynamic pressure gas film 103 is located between the inner surface 102 of the bearing and the rotating shaft 101. When the pressure of the dynamic pressure gas film 103 is large enough to support the load, the rotating shaft 101 will be suspended, and the friction force will disappear.

[0004] Air foil bearings have a series of advantages such as low friction loss, almost no friction at extremely high speeds, good high-temperature stability, low vibration, and no need for lubricating oil. They are widely used in air cycle machines, air blowers, fuel cell air compressors, micro gas turbines and other machinery. They have very broad application prospects in the fields of low-temperature and high-temperature technology, high-speed turbines and space technology.

[0005] However, the manufacturing process of common corrugated foil air foil bearings is long and complex, and the installation precision requirements are high and the manufacturing consistency is difficult to control. Under complex working conditions such as vehicle-mounted fuel cell air compressors, the application development of air foil bearings is limited to a certain extent due to their low damping and poor impact resistance. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a radial gas foil bearing to solve the technical problem that the air foil bearing used in the prior art has low damping and poor impact resistance, which to a certain extent limits its application development under complex working conditions such as vehicle-mounted fuel cell air compressors.

[0007] In order to achieve the above object, an embodiment of the present invention provides a radial gas foil bearing, comprising a bearing sleeve, a top foil and a bottom foil, and also comprising a foil elastic component, wherein:

[0008] The bearing sleeve, the top foil, the bottom foil and the foil elastic component are all arranged in a cylindrical shape with two ends open, and the bearing sleeve, the bottom foil, the foil elastic component and the top foil are sequentially sleeved from the outside to the inside, and the bottom foil, the foil elastic component and the top foil are all detachably connected to the inner side wall of the bearing sleeve;

[0009] The foil elastic components can undergo elastic deformation and rub against each other to increase the damping of the bearing.

[0010] Preferably, the foil elastic component includes a full-circumference support foil and a cantilever support foil, the full-circumference support foil is cylindrical with openings at both ends, the cantilever support foil is tangentially fixedly installed on the outer side wall of the full-circumference support foil, and the cantilever support foil can undergo elastic deformation.

[0011] Preferably, the cantilever support foil includes a plurality of pieces, and the plurality of cantilever support foils surround the outer side wall of the full-circumference support foil.

[0012] Preferably, saw teeth are provided on the cantilever support foil, and the saw teeth are located in the radial direction of the entire circumference support foil.

[0013] Preferably, the saw teeth are arranged in a strip shape or a triangle shape.

[0014] Preferably, the saw teeth include a plurality of saw teeth distributed on one side or both sides of the cantilever support foil.

[0015] Preferably, the circumferential support foil comprises a free end and a fixed end, the free end and the fixed end are both arranged along the axial direction of the circumferential support foil, and the fixed end is used to be clamped on the inner side wall of the bearing sleeve.

[0016] Preferably, the cantilever support foil is welded to the outer side wall of the full-circumference support foil along the axial center line of the full-circumference support foil.

[0017] Preferably, it further comprises an O-ring, which is sleeved on the outer side wall of the bearing sleeve.

[0018] Preferably, an axial groove corresponding to the O-ring is provided on the outer side wall of the bearing sleeve, and the O-ring is installed on the outer side wall of the bearing sleeve through the axial groove.

[0019] The radial gas foil bearing provided by the present invention has the following technical effects:

[0020] This radial gas foil bearing is mainly composed of a bearing sleeve, a top foil, a bottom foil and a foil elastic component. Compared with the traditional gas foil bearing, a foil elastic component is added. The foil elastic component is installed between the top foil and the bottom foil, and is detachably installed on the inner wall of the bearing sleeve. When the rotating shaft is installed inside the radial gas foil bearing, due to the existence of the dynamic air film, the foil elastic component undergoes elastic deformation, which increases the friction between the foil elastic component and the contact object, thereby achieving the purpose of increasing the bearing damping, overcoming the defects of the air foil bearing in the prior art due to its low damping and poor impact resistance, which to a certain extent limits its application development. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the principle structure of an air foil bearing in the prior art;

[0023] Figure 2 yes Figure 1 A partial enlarged diagram of the schematic diagram of the principle structure of the hollow foil bearing;

[0024] Figure 3 is an exploded view of a radial gas foil bearing according to an embodiment of the present invention;

[0025] Figure 4 yes Figure 3 A three-dimensional structural diagram of the mid-radial gas foil bearing after installation;

[0026] Figure 5 yes Figure 3 Side view of a mid-radial gas foil bearing;

[0027] Figure 6 yes Figure 3 A three-dimensional structural diagram of the foil elastic component of the mid-radial gas foil bearing;

[0028] Figure 7 yes Figure 6 Expanded view of the foil elastic assembly of a mid-radial gas foil bearing.

[0029] in, Figure 1-Figure 7 :

[0030] 101. rotating shaft; 102. inner surface of bearing; 103. dynamic pressure air film; 2. bearing sleeve; 201. slot; 3. top foil; 301. top foil insertion part; 4. bottom foil; 401. bottom foil insertion part; 5. foil elastic component; 51. cantilever supporting foil; 511. serration; 52. full-circle supporting foil; 53. free end; 54. fixed end; 6. O-ring. DETAILED DESCRIPTION

[0031] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0032] In the description of the present invention, it should be noted that, unless otherwise specified, "multiple" means two or more than two; the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0034] As described in the background technology, the manufacturing process of the corrugated foil type air foil bearing used in the prior art is long and complex, and the installation precision requirements are high and the manufacturing consistency is difficult to control. Under complex working conditions such as vehicle-mounted fuel cell air compressors, the air foil bearing has low damping and poor impact resistance, which to a certain extent limits its application development.

[0035] Based on this, the present invention provides a radial gas foil bearing, which, compared with the traditional gas foil bearing, adds a foil elastic component, and the foil elastic component is installed between the top foil and the bottom foil, and is detachably installed on the inner wall of the bearing sleeve. When the rotating shaft is installed inside the radial gas foil bearing, due to the existence of the dynamic air film, the foil elastic component undergoes elastic deformation, which increases the friction between the foil elastic component and the contact object, thereby achieving the purpose of increasing the bearing damping, overcoming the defects of the air foil bearing in the prior art due to its low damping and poor impact resistance, which to a certain extent limits its application development.

[0036] Specifically, the embodiment of the present invention provides a radial gas foil bearing, including a bearing sleeve 2, a top foil 3 and a bottom foil 4, and also includes a foil elastic component 5, such as Figure 3-Figure 7 As shown, the bearing sleeve 2, the top foil 3, the bottom foil 4 and the foil elastic component 5 are all arranged in a cylindrical shape with openings at both ends, and the bearing sleeve 2, the bottom foil 4, the foil elastic component 5 and the top foil 3 are sequentially arranged from the outside to the inside, that is, after the rotating shaft is installed, the top foil 3 is directly adjacent to the rotating shaft, and the bottom foil 4, the foil elastic component 5 and the top foil 3 are all detachably connected to the inner wall of the bearing sleeve 2; the foil elastic component 5 can undergo elastic deformation and friction with each other to increase the damping of the bearing.

[0037] The bottom foil 4, the foil elastic component 5 and the top foil 3 are all detachably connected to the inner wall of the bearing sleeve 2. Specifically, the inner wall of the bearing sleeve 2 has a plurality of slots 201, the bottom foil 4 has a bottom foil insertion portion 401, and the top foil 3 has a top foil insertion portion 301. Figure 3-Figure 5 As shown, the bottom foil insertion portion 401 extends radially outward along the bottom foil 4. Similarly, the top foil insertion portion 301 also extends radially outward along the top foil 3. Both the bottom foil insertion portion 401 and the top foil insertion portion 301 can be inserted into the slot 201 of the bearing sleeve 2, thereby achieving the purpose of detachable connection.

[0038] In one embodiment of the present invention, the foil elastic component 5 specifically includes a full-circumference support foil 52 and a cantilever support foil 51. Figure 6 and Figure 7 As shown, the whole-circumference support foil 52 is in the shape of a cylinder with openings at both ends so as to be sleeved on the outer wall of the top foil 3. The cantilever support foil 51 is tangentially fixedly installed on the outer wall of the whole-circumference support foil 52. The cantilever support foil 51 can undergo elastic deformation, which is caused by the dynamic pressure air film. After the elastic deformation, the cantilever support foil 51 can increase the friction inside the bearing, thereby achieving the purpose of increasing the bearing damping.

[0039] Further, the cantilever support foil 51 includes several pieces, such as Figure 6 and Figure 7 As shown, it includes seven rectangular cantilever support foils 51, and the seven cantilever support foils 51 are surrounded on the outer side wall of the full-circle support foil 52. Each cantilever support foil 51 is tangent to the outer side wall of the full-circle support foil 52, and the tangent point is on the axial center line of the cantilever support foil 51 along the full-circle support foil 52. The cantilever support foil 51 is welded to the full-circle support foil 52.

[0040] It should be understood that the present invention does not limit the number of cantilever support foils 51, which is determined by the radius of the full-circumference support foil 52 and the number of cantilever support foils 51. As long as the cantilever support foil 51 can be fixedly installed tangentially on the outer wall of the full-circumference support foil 52 and can undergo elastic deformation when affected by the dynamic pressure air film, it is within the protection scope of the present invention.

[0041] It should also be understood that the present invention does not limit the shape of the cantilever support foil 51, that is, it is not limited to a rectangle, it can be a square, or other shapes, such as a polygon. As long as the cantilever support foil 51 can be fixedly installed tangentially on the outer wall of the entire circumference support foil 52, it can undergo elastic deformation when affected by the dynamic pressure air film, which is within the protection scope of the present invention.

[0042] It should be further understood that the cantilever support foil 51 and the full-circle support foil 52 are not limited to welding, and other fixed connection methods can also be used, which are not listed one by one here. The fixed connection methods in the prior art can all achieve the connection between the cantilever support foil 51 and the full-circle support foil 52.

[0043] Furthermore, in order to realize the detachable connection between the whole circumference support foil 52 and the bearing sleeve 2, the whole circumference support foil 52 includes a free end 53 and a fixed end 54, such as Figure 6 and Figure 7 As shown, the free end 53 and the fixed end 54 are both arranged along the axial direction of the circumferential support foil 52, and the free end 53 abuts against the root of the fixed end 54, so that the circumferential support foil 52 forms a cylindrical shape, and the fixed end 54 is used to be clamped on the inner wall of the bearing sleeve 2, specifically, the fixed end 54 is inserted into the clamping groove 201 of the bearing sleeve 2, thereby realizing the detachable connection between the circumferential support foil 52 and the bearing sleeve 2.

[0044] It should be noted that the present invention is not limited to realizing the detachable connection by means of a snap connection between the fixed end 54 and the bearing sleeve 2 , and other detachable connection methods are also possible, all of which are within the protection scope of the present invention.

[0045] In addition, after the bottom foil 4, the circumferential supporting foil 52 and the top foil 3 are inserted into the slot 201 of the bearing sleeve 2, a pin is then inserted into the slot 201, thereby achieving the purpose of further fixing.

[0046] In a further embodiment of the present invention, in order to adjust the stiffness of the bearing within an adjustable range, a sawtooth 511 is provided on the cantilever support foil 51, such as Figure 3 , Figure 6 and Figure 7 As shown, the saw teeth 511 are located in the radial direction of the entire circumferential support foil 52, are strip-shaped, and include several saw teeth distributed on both sides of the cantilever support foil 51. The saw teeth 511 in the figure can be distributed at equal intervals or at non-equal intervals, depending on the actual application scenario or actual process conditions.

[0047] That is, when the load is large, a large rigidity support is used, and when the load is small, a small rigidity support is used. The specific number and shape of the saw teeth 511 are adjusted according to the required rigidity.

[0048] It should be understood that the shape of the sawtooth 511 is not limited to a bar, and can be a triangle, a rhombus, or other shapes. The specific shape of the sawtooth 511 is determined based on the stiffness requirements of the bearing. Regardless of the shape, it is within the protection scope of the present invention.

[0049] It should also be understood that the present invention also does not limit the number of saw teeth 511, and the specific number of saw teeth 511 is determined based on the stiffness requirements of the bearing. No matter how many saw teeth 511 there are, they are within the protection scope of the present invention.

[0050] It should be further understood that the saw teeth 511 may be distributed on one side of the cantilever support foil 51 , or may be distributed on both sides of the cantilever support foil 51 , and the present invention is not limited thereto.

[0051] In another further embodiment of the present invention, in order to further increase the damping characteristics of the bearing and improve the impact resistance of the bearing, an O-ring 6 is also included. Figure 3 As shown, the O-ring 6 is sleeved on the outer wall of the bearing sleeve 2, and an axial groove corresponding to the O-ring 6 is arranged on the outer wall of the bearing sleeve 2. The O-ring 6 is installed on the outer wall of the bearing sleeve 2 through the axial groove.

[0052] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A radial gas foil bearing, comprising a bearing sleeve, a top foil and a bottom foil, characterized in that: Also included is a foil elastic assembly, wherein: The bearing sleeve, the top foil, the bottom foil and the foil elastic component are all arranged in a cylindrical shape with two ends open, and the bearing sleeve, the bottom foil, the foil elastic component and the top foil are sequentially sleeved from the outside to the inside, and the bottom foil, the foil elastic component and the top foil are all detachably connected to the inner side wall of the bearing sleeve; The foil elastic components can undergo elastic deformation and rub against each other to increase the damping of the bearing; The foil elastic component includes a full-circumference support foil and a cantilever support foil, the full-circumference support foil is in the shape of a cylinder with two ends open, the cantilever support foil is tangentially fixedly installed on the outer side wall of the full-circumference support foil, and the cantilever support foil can undergo elastic deformation; The cantilever support foil includes a plurality of pieces, and the plurality of cantilever support foils surround the outer side wall of the full-circumference support foil; The cantilever support foil is provided with saw teeth, and the saw teeth are located in the radial direction of the entire circumference support foil.

2. The radial gas foil bearing according to claim 1, characterized in that: The saw teeth are arranged in a strip shape or a triangle shape.

3. The radial gas foil bearing according to claim 1, characterized in that: The saw teeth include a plurality of saw teeth distributed on one side or both sides of the cantilever supporting foil.

4. The radial gas foil bearing according to claim 1, characterized in that: The full-circle supporting foil comprises a free end and a fixed end. Both the free end and the fixed end are arranged along the axial direction of the full-circle supporting foil. The fixed end is used for clamping on the inner side wall of the bearing sleeve.

5. The radial gas foil bearing according to claim 1, characterized in that: The cantilever support foil is welded to the outer side wall of the full-circumference support foil along the axial center line of the full-circumference support foil.

6. The radial gas foil bearing according to any one of claims 1 to 5, characterized in that: It also includes an O-ring, which is sleeved on the outer side wall of the bearing sleeve.

7. The radial gas foil bearing according to claim 6, characterized in that: An axial groove corresponding to the O-ring is arranged on the outer side wall of the bearing sleeve, and the O-ring is installed on the outer side wall of the bearing sleeve through the axial groove.

Images