Flap type dynamic pressure air floatation radial bearing

Abstract

The utility model relates to a petal-type dynamic pressure air floatation radial bearing, which comprises a bearing seat, which comprises a bearing hole; the bearing comprises a bearing hole, a plurality of groups of foil assemblies, the plurality of groups of foil assemblies are sequentially arranged along the circumferential direction of the inner wall of the bearing hole, each group of foil assembly comprises a supporting bump foil and a top layer foil which are formed by vertically overlapping, the top layer foil is used for bearing a rotor, and a wedge-shaped gap is formed between the top layer foil and the rotor. According to the petal type dynamic pressure air floatation radial bearing, the cavity allowing the rotor to penetrate through is defined by the three or more sets of foil assemblies, when the rotor penetrates through the cavity, a plurality of wedge-shaped gaps are formed, when the rotor rotates at a high speed, air continuously enters the wedge-shaped gaps, the pressure of an air film is increased, air film supporting force is formed, and therefore the rotor is stably suspended in the cavity. According to the utility model, stable air film supporting force can be provided, the stability of the rotor is improved, and the vibration of the rotor is suppressed.

Description

Technical Field

[0001] The present disclosure relates to the field of gas bearings, and in particular to a petal-type dynamic pressure air-floating radial bearing. Background Art

[0002] Foil gas bearing is a kind of dynamic pressure gas bearing with elastic support structure. Since it uses the dynamic pressure effect of wedge-shaped gas film to provide bearing capacity for the rotor, it does not require an external gas source. It has the advantages of high speed, low friction loss, low maintenance cost and the ability to be used in high and low temperature environments. It is widely used in high-speed rotating machinery such as hydrogen fuel cell air compressors, air suspension centrifugal blowers, aircraft environmental control systems and micro gas turbines.

[0003] The foil gas bearing essentially uses the dynamic pressure effect of the wedge-shaped air film between the top foil and the rotor to generate a circumferential pressure difference to support the high-speed operation of the rotor. The circumferential wedge-shaped compressed air film can provide a supporting load for the rotor's own weight.

[0004] In the existing full-circle structure dynamic pressure air bearing, in the initial state, the inner hole of the bearing is close to a full circle, and it needs to rely on the gravity of the rotating shaft to act on the gas bearing, and it is eccentric relative to the gas bearing, thereby forming a wedge-shaped gap on the inner surface of the air bearing. This type of dynamic pressure air bearing has the following problems: low processing production efficiency and qualified rate; narrow applicable rotating shaft weight; the rotating shaft can only be placed approximately horizontally, not vertically; narrow applicable speed range; weak vibration suppression ability. Existing overlap-type air bearings have the disadvantages of complex structure, short start-stop life, low load-bearing capacity, and short service life. Utility Model Content

[0005] In view of the above, it is necessary to provide a flap-type dynamic pressure air-floating radial bearing, which can improve the working stability of the rotor.

[0006] To this end, the present disclosure provides a petal-type dynamic pressure air-floating radial bearing, comprising:

[0007] A bearing seat, including a bearing hole;

[0008] A plurality of groups of foil assemblies are sequentially arranged along the circumferential direction of the inner wall of the bearing hole, each group of the foil assemblies comprises a supporting wave foil and a top layer foil stacked up and down, the top layer foil is used to support the rotor, a wedge-shaped gap is provided between the top layer foil and the rotor, and the supporting wave foil is used to support the load applied to the supporting wave foil by the compressed gas film formed by the rotor.

[0009] According to the petal-type dynamic pressure air-floating radial bearing, the foil assembly includes a fixed end and a free end in sequence along the rotation direction of the rotor, the fixed end is connected to the bearing seat, and the free end extends along the circumferential direction of the bearing hole.

[0010] According to the petal-type dynamic pressure air-floating radial bearing, the wedge-shaped gap is provided between the free end of the top foil and the rotor.

[0011] According to the petal-type dynamic pressure air-floating radial bearing, the wedge-shaped gap is located between the beginning of the free end of the top foil and the rotor or between the end of the free end of the top foil and the rotor.

[0012] According to the petal-type dynamic pressure air-floating radial bearing, the bearing hole is provided with a fixed groove body, and the fixed groove body has a first groove body extending along the central axis direction of the bearing hole and a second groove body extending in the opposite direction of the rotor rotation at the extended end of the first groove body. The fixed end of the foil assembly is provided with a positioning structure, and the positioning structure is inserted into the fixed groove body to fix the foil assembly in the circumferential direction.

[0013] According to the petal-type dynamic pressure air-floating radial bearing, the wedge-shaped gap gradually decreases along the rotation direction of the rotor.

[0014] According to the petal-type dynamic pressure air-floating radial bearing, the maximum height of the wedge-shaped gap is h, the length of the wedge-shaped gap and the central angle formed by the axis of the rotor is X, and the height h and the central angle X satisfy: 0.05 mm <h<0.5mm,5°<X<50°。

[0015] According to the flap-type dynamic pressure air-floating radial bearing, the foil assembly further comprises a bottom foil, the bottom foil is stacked on the supporting wave foil, and the bottom foil is in contact with the inner wall of the bearing hole.

[0016] According to the petal-type dynamic pressure air-floating radial bearing, the supporting wave foil is a corrugated elastic supporting member having a plurality of protrusions, wherein the protrusions include a first supporting sheet and a second supporting sheet bent in a radial direction, wherein the first supporting sheet and the second supporting sheet protrude in opposite directions in the radial direction, wherein the first supporting sheet contacts the top foil, and the second supporting sheet contacts the bearing hole.

[0017] According to the petal-type dynamic pressure air-floating radial bearing, the first support piece is an arc-shaped protrusion, and the second support piece is a plane protrusion, and the plane protrusion is matched with the inner wall of the bearing hole.

[0018] Compared with the prior art, the above-mentioned flap-type dynamic pressure air-floating radial bearing uses three or more sets of foil assemblies to form a cavity for the rotor to pass through. When the rotor passes through the cavity, multiple wedge-shaped gaps are formed between the rotor and the foil assembly. When the rotor rotates at high speed, gas continuously enters the wedge-shaped gaps, causing the air film pressure to rise, forming an air film support force, so that the rotor is stably suspended in the cavity. The utility model can provide a stable air film support force, improve the stability of the rotor, and suppress the vibration of the rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods, the drawings required for use in the description of the implementation methods will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a structural schematic diagram of a flap-type dynamic pressure air-floating radial bearing.

[0021] Figure 2 It is a schematic diagram of the side structure of the flap-type dynamic pressure air-floating radial bearing when the rotor rotates in the positive direction.

[0022] Figure 3 yes Figure 2 An enlarged schematic diagram of part A.

[0023] Figure 4 It is a schematic diagram of the side structure of the flap-type dynamic pressure air-floating radial bearing when the rotor rotates in the opposite direction.

[0024] Figure 5 yes Figure 4 An enlarged schematic diagram of part B.

[0025] Figure 6 It is a schematic diagram of the structure of the foil assembly.

[0026] Main component symbols

[0027] Bearing seat 1 Rotor 2 Foil components 3 Support foil 4 Top foil 5 Wedge gap 6 Fixed tank 7 Bottom foil 8 First supporting sheet 9 Second supporting sheet 10 Fixed protrusion 11

[0028] The following specific implementations will further illustrate the present disclosure in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0029] In order to more clearly understand the above-mentioned purposes, features and advantages of the present disclosure, the present disclosure is described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. In the following description, many specific details are set forth in order to fully understand the present disclosure, and the described embodiments are only part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs. The terms used in the specification herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure.

[0031] In each embodiment, for the convenience of description and not to limit the present disclosure, the term "connection" used in the patent specification and claims of the present disclosure is not limited to physical or mechanical connection, but may include electrical connection, whether direct or indirect. "Up", "down", "below", "left", "right", etc. are only used to indicate relative position relationship. When the absolute position of the described object changes, the relative position relationship also changes accordingly.

[0032] like Figures 1 to 6 As shown, the flap-type dynamic pressure air-floating radial bearing comprises a bearing seat 1 and a plurality of foil assemblies 3. Each foil assembly comprises a supporting wave foil 4 and a top foil 5, which are sequentially arranged in the bearing seat 1 to support the high-speed rotation of the rotor 2.

[0033] The bearing seat 1 includes a bearing hole. The bearing seat 1 is generally in a columnar structure and has a bearing hole that penetrates in the axial direction. The rotor 2 can be installed in the bearing hole and rotate at a high speed relative to the bearing seat 1. The inner wall of the bearing hole is provided with a plurality of mounting bayonet holes arranged in the circumferential direction for fixing the foil assembly 3 in a bayonet manner.

[0034] Several groups of foil assemblies 3 are sequentially arranged along the inner wall of the bearing hole in the circumferential direction. In this embodiment, the number of foil assemblies 3 is three groups, which are uniformly arranged in the circumferential direction. In other embodiments, the number of foil assemblies 3 can also be 4 groups, 5 groups or other numbers, which are uniformly arranged in the circumferential direction.

[0035] Each group of foil assemblies 3 includes a supporting wave foil 4 and a top foil 5 stacked up and down, and the top foil 5 is used to support the rotor 2. There is a wedge-shaped gap 6 between the top foil 5 and the rotor 2, and the supporting wave foil 4 is used to carry the load applied to the top foil 5 by the compressed air film formed by the rotor 2, and is used to carry the load of the top foil 5.

[0036] The foil assembly 3 includes a fixed end and a free end in the rotation direction of the rotor 2. The fixed end is connected to the bearing seat 1, and the free end extends along the circumferential direction of the bearing hole. The part of the foil assembly 3 that is clamped and installed on the bearing seat 1 is the fixed end, and the part that extends and installs inside the bearing hole is the free end.

[0037] In each group of foil assemblies 3, one end of the top foil 5 is provided with a fixed end corresponding to the bayonet, and the other end (free end) extends along the circumferential direction of the bearing hole. The fixed end is connected to the bayonet of the bearing seat 1, and the free end extends along the circumferential direction of the inner wall of the bearing hole. A wedge-shaped gap 6 is provided between the free end of the top foil 5 and the rotor 2. As a specific embodiment, the wedge-shaped gap 6 can be provided between the starting end of the free end of the top foil 5 and the rotor 2 or between the end of the free end of the top foil 5 and the rotor 2. When the rotor rotation direction is from the fixed end of the top foil 5 to the free end, the wedge-shaped gap 6 can be provided between the starting end of the free end of the top foil 5 and the rotor 2; when the rotor rotation direction is from the free end of the top foil to the fixed end, the wedge-shaped gap 6 can be provided between the end of the free end of the top foil 5 and the rotor 2. Similarly, one end of the supporting wave foil 4 is provided with a fixed end corresponding to the bayonet, and the free end extends along the circumferential direction of the bearing hole. The fixed end is connected to the bayonet of the bearing seat 1, and the free end extends along the circumferential direction of the inner wall of the bearing hole.

[0038] The foil assembly 3 also includes a bottom foil 8, which is stacked on the supporting wave foil 4, and the bottom foil 4 is in contact with the inner wall of the bearing hole. The bottom foil 8 isolates the supporting wave foil 4 from the bearing seat 1, and the bottom foil 8 mainly plays a protective role to reduce the wear of the bearing seat 1. When the bearing seat 1 is made of relatively soft materials such as aluminum and plastic, the bottom foil 8 needs to be installed; when the bearing seat 1 is made of harder or wear-resistant materials, the bottom foil 8 can be omitted. Similarly, one end of the bottom foil 8 is provided with a fixed end corresponding to the bayonet, and the free end extends along the circumferential direction of the bearing hole. The fixed end is connected to the bayonet of the bearing seat 1, and the free end extends along the circumferential direction of the inner wall of the bearing hole.

[0039] In order to better fix the foil assembly 3, the bearing hole is provided with a fixed slot 7, the fixed slot 7 has a first slot extending along the central axis direction of the bearing hole and a second slot extending in the opposite direction of the rotation of the rotor 2 at the extended end of the first slot, and the fixed end of the foil assembly 3 is provided with a positioning structure, and the positioning structure is inserted into the fixed slot 7 to fix the foil assembly 3 in the circumferential direction. As a specific embodiment, the fixed end of the foil assembly 3 can be provided with a fixing protrusion 11, and the fixing protrusion 11 is inserted into the fixed slot 7 to fix the foil assembly 3 in the circumferential direction. Of course, the positioning structure can also be fixed by a buckle or the like. This embodiment adopts three groups of foil assemblies 3, and the bearing hole is correspondingly provided with three fixing slots 7 for installing the foil assembly 3.

[0040] The wedge-shaped gap 6 gradually decreases along the rotation direction of the rotor 2 until it is zero. The direction in which the wedge-shaped gap 6 gradually decreases is consistent with the rotation direction of the rotor 2. The maximum height of the wedge-shaped gap 6 is h, and the central angle formed by the length of the wedge-shaped gap 6 and the axis of the rotor 2 is X. The height h and the central angle X satisfy: 0.05mm <h<0.5mm,5°<X<50°。

[0041] The support foil 4 is a corrugated elastic support member with a plurality of protrusions, including a first support sheet 9 and a second support sheet 10 bent in the radial direction. The first support sheet 9 and the second support sheet 10 protrude in opposite directions in the radial direction. The first support sheet 9 contacts the top foil 5, and the second support sheet 10 contacts the bearing hole. The first support sheet 9 is an arc-shaped protrusion, and the second support sheet 10 is a plane protrusion, which matches the inner wall of the bearing hole. If the bearing seat 1 is installed with the bottom foil 8, the second support sheet 10 contacts the bottom foil 8, and the plane protrusion of the second support sheet 10 matches the inner wall of the bottom foil 8.

[0042] The foil assembly 3 is preset with a wedge-shaped gap 6 corresponding to the foil assembly 3. When the rotor 2 rotates at a high speed, an air floating support force is generated between the rotor 2 and the foil assembly 3, which is applicable to a large range of shaft weight and a wide range of rotation speeds; the vibration suppression capability is significantly improved; the load-bearing capacity is strong; the start-stop life and service life are long; the impact and random vibration resistance are significantly improved; and the production efficiency and the qualified rate are significantly improved.

[0043] In the several specific embodiments provided in the present disclosure, it is obvious to those skilled in the art that the present disclosure is not limited to the details of the above exemplary embodiments, and that the present disclosure can be implemented in other specific forms without departing from the spirit or basic features of the present disclosure. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present disclosure is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present disclosure. In addition, it is obvious that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. The words first, second, etc. are used to indicate names, and do not indicate any particular order.

[0044] The above embodiments are only used to illustrate the technical solution of the present disclosure rather than to limit it. Although the present disclosure is described in detail with reference to the above preferred embodiments, those skilled in the art should understand that the technical solution of the present disclosure can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present disclosure.

Claims

1. A petal-type dynamic pressure air-floating radial bearing, characterized in that: include: A bearing seat, including a bearing hole; A plurality of groups of foil assemblies are sequentially arranged along the circumferential direction of the inner wall of the bearing hole, each group of the foil assemblies comprises a supporting wave foil and a top layer foil stacked up and down, the top layer foil is used to support the rotor, a wedge-shaped gap is provided between the top layer foil and the rotor, and the supporting wave foil is used to support the load applied to the supporting wave foil by the compressed gas film formed by the rotor.

2. The petal-type dynamic pressure air-floating radial bearing according to claim 1, characterized in that: The foil assembly comprises a fixed end and a free end in sequence along the rotation direction of the rotor, the fixed end is connected to the bearing seat, and the free end extends along the circumferential direction of the bearing hole.

3. The petal-type dynamic pressure air-floating radial bearing according to claim 2, characterized in that: The wedge-shaped gap is provided between the free end of the top foil and the rotor.

4. The petal-type dynamic pressure air-floating radial bearing according to claim 2, characterized in that: The wedge-shaped gap is located between the beginning of the free end of the top foil and the rotor or between the end of the free end of the top foil and the rotor.

5. The petal-type dynamic pressure air-floating radial bearing according to claim 2, characterized in that: The bearing hole is provided with a fixed groove body, and the fixed groove body has a first groove body extending along the central axis direction of the bearing hole and a second groove body extending in the opposite direction of the rotor rotation at the extended end of the first groove body. The fixed end of the foil assembly is provided with a positioning structure, and the positioning structure is inserted into the fixed groove body to fix the foil assembly along the circumferential direction.

6. The petal-type dynamic pressure air-floating radial bearing according to claim 1, characterized in that: The wedge-shaped gap gradually decreases along the rotation direction of the rotor.

7. The petal-type dynamic pressure air-floating radial bearing according to claim 6, characterized in that: The maximum height of the wedge-shaped gap is h, the length of the wedge-shaped gap and the central angle formed by the axis of the rotor is X, and the height h and the central angle X satisfy: 0.05 mm <h<0.5mm,5°<X<50°。 8. The petal-type dynamic pressure air-floating radial bearing according to claim 1, characterized in that: The foil assembly further comprises a bottom foil, wherein the bottom foil is stacked on the supporting wave foil, and the bottom foil contacts the inner wall of the bearing hole.

9. The petal-type dynamic pressure air-floating radial bearing according to claim 1, characterized in that: The supporting wave foil is a corrugated elastic supporting member having a plurality of protrusions, wherein the protrusions include a first supporting sheet and a second supporting sheet bent in a radial direction, wherein the first supporting sheet and the second supporting sheet protrude in opposite directions in the radial direction, wherein the first supporting sheet contacts the top foil, and the second supporting sheet contacts the bearing hole.

10. The petal type dynamic pressure air floating radial bearing according to claim 9, characterized in that: The first supporting piece is an arc-shaped protrusion, and the second supporting piece is a plane protrusion, and the plane protrusion is matched with the inner wall of the bearing hole.

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