Gas bearing coating wear detection device and gas bearing drive system

Abstract

The application discloses a kind of gas bearing coating wear detection device and gas bearing transmission system, the gas bearing coating wear detection device includes rotor, bearing sleeve and electric signal analysis component, the outer circumferential surface of rotor is equipped with array distribution conductive tab, bearing sleeve is equipped in the outer circumferential surface of rotor, and the inside of bearing sleeve is equipped with two back electrodes, the surface of back electrode is coated with self-lubricating coating, the bottom surface of back electrode is coated with insulating coating, two back electrodes are connected with electric signal signal analysis component by wire to transport electric signal, electric signal analysis component is used to calculate the wear state of self-lubricating coating and rotor speed according to received electric signal.The gas bearing coating wear detection device of the application can not only realize the synchronous on-line monitoring of gas bearing coating wear depth and rotor speed, but also realize coating failure early warning.

Description

Technical Field

[0001] The present invention relates to the technical field of bearings, and in particular to a gas bearing coating wear detection device and a gas bearing transmission system. Background Art

[0002] Self-lubricating coatings are a common method for reducing friction and wear on the surface of mechanical parts and can be used between any parts that move relative to each other. Among them, air bearings are increasingly being used in high-speed rotating equipment because of their low resistance, allowing for higher speeds while maintaining low vibration levels. However, during the initial startup of air bearings, dry friction between the rotor and the bearings can cause wear on the material surface. In order to accurately calculate the service life of air bearings and ensure the reliability of their operation, wear monitoring equipment is required to monitor the wear status of the air bearing surface coating. However, the wear monitoring equipment in related technologies has the problems of large size and poor integration. In addition, the compact structure of foil air bearings and the thin coating thickness make it difficult to achieve online monitoring of the wear status of embedded coatings. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to propose a gas bearing coating wear detection device in response to the defects and shortcomings of the existing technology, which can realize online monitoring of the coating wear depth and rotor speed of the gas bearing.

[0004] The gas bearing coating wear detection device of an embodiment of the present invention includes: a rotor, wherein an array of conductive electrodes are provided on the outer circumference of the rotor; a bearing sleeve, wherein the bearing sleeve is provided on the outer circumference of the rotor, and the inner side of the bearing sleeve is coated with an insulating coating, and two back electrodes are provided on the inner side of the insulating coating, and the surface of the back electrode is covered with a self-lubricating coating. At the initial stage of starting the rotor, the conductive electrode contacts and rubs with the self-lubricating coating, and the conductive electrode can sweep across the area where the back electrode is located as the rotor rotates; an electrical signal analysis component, wherein the two back electrodes are connected to the electrical signal analysis component through wires to transmit wear electrical signals and speed electrical signals, and the electrical signal analysis component is used to infer the wear state of the self-lubricating coating based on the received wear electrical signals and to infer the rotor speed based on the received speed electrical signals.

[0005] In a gas bearing coating wear detection device according to an embodiment of the present invention, a conductive electrode is provided on the outer circumference of the rotor, a bearing sleeve is disposed on the outer circumference of the rotor, and two back electrodes are disposed on the inner side of the bearing sleeve. The surfaces of the back electrodes are coated with a self-lubricating coating. The two back electrodes are connected to an electrical signal analysis component via wires to transmit wear and speed electrical signals. As the self-lubricating coating wears, the coating thickness changes, affecting the electrostatic induction of the back electrodes. Furthermore, a large amount of wear debris is generated, causing the net charge on the coating and the rotor surface to change. The combined effect of these two factors causes the open-circuit voltage between the back electrodes to vary with the wear depth. The electrical signal analysis component analyzes the changes in the wear electrical signal to achieve online monitoring of the coating wear depth. Simultaneously, as the rotor rotates, the potential on the back electrodes changes periodically, thereby generating a periodic electrical signal. Because the output frequency of the electrical signal between the electrodes is linearly correlated with the rotor rotation frequency, quantitative monitoring of the rotor speed can be achieved based on the frequency of the electrical signal. Furthermore, because the back electrodes are directly integrated within the self-lubricating coating on the bearing surface, compared to conventional wear detection devices, this device solves the problem of gas bearings being compact and thus unsuitable for detection devices.

[0006] In some embodiments, the surface of the rotor is coated with the conductive electrode sheet, or a groove is provided on the surface of the rotor, and the conductive electrode sheet is embedded in the groove.

[0007] In some embodiments, the gas bearing coating wear detection device also includes a corrugated foil and a top foil, the top foil is arranged on the inner side of the bearing sleeve, the corrugated foil is arranged on the inner circumferential surface of the bearing sleeve and is located between the top foil and the bearing sleeve, and the self-lubricating coating is arranged on the inner side of the top foil and covers the back electrode.

[0008] In some embodiments, an insulating coating is provided on the inner circumferential surface of the top foil, and the back motor sheet is provided on the inner side of the insulating coating.

[0009] In some embodiments, the conductive electrode sheets are multiple and spaced apart in the circumferential direction of the rotor.

[0010] In some embodiments, there are two conductive electrode sheets, and the two conductive electrode sheets are arranged opposite to each other on different sides of the rotor in the radial direction of the rotor.

[0011] In some embodiments, the back electrode is a copper sheet.

[0012] In some embodiments, the extension length of the back electrode in the axial direction of the rotor is L, and the axial length of the bearing sleeve is L1, then the following conditions are satisfied: 0.5L1≤L≤0.9L1;

[0013] In some embodiments, the sector angle α of the back electrode satisfies 20°≤α≤80°, and the gap angle β between adjacent back electrodes satisfies 10°≤β≤80°.

[0014] The gas bearing transmission system of the embodiment of the present invention includes the gas bearing coating wear detection device described in any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the structure of a gas bearing coating wear detection device according to an embodiment of the present invention.

[0016] Reference numerals:

[0017] Conductive electrode sheet 1, bearing sleeve 2, corrugated foil 3, top foil 4, insulating coating 5, back electrode 6, self-lubricating coating 7, rotor 8. DETAILED DESCRIPTION

[0018] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0019] like Figure 1 As shown, the gas bearing coating wear detection device according to the embodiment of the present invention includes a rotor 8, a bearing sleeve 2 and an electrical signal analysis component.

[0020] Specifically, an array of conductive electrode sheets 1 are provided on the outer circumference of the rotor 8, a bearing sleeve 2 is provided on the outer circumference of the rotor 8, and the inner side of the bearing sleeve 2 is coated with an insulating coating, two back electrodes 6 are provided on the inner side of the insulating coating, and the surface of the back electrode 6 is covered with a self-lubricating coating 7. At the initial start-up of the rotor 8, the conductive electrode sheet 1 contacts and rubs against the self-lubricating coating 7, and the conductive electrode sheet 1 can sweep across the area where the back electrode 6 is located as the rotor 8 rotates. The two back electrodes 6 are connected to the electrical signal analysis component through wires to transmit wear electrical signals and speed electrical signals. The electrical signal analysis component is used to infer the wear state of the self-lubricating coating 7 based on the received wear electrical signals and to infer the rotor speed based on the received speed electrical signals.

[0021] It can be understood that during the operation of the gas bearing, the rotation of the rotor 8 will drive the rotation of the conductive electrode 1. When the surface of the conductive electrode 1 contacts the self-lubricating coating 7, due to the difference in the ability of the materials to gain and lose electrons, the charge will be transferred between the two surfaces, so that the two surfaces have equal but opposite charges. The surface charge of the material causes the back electrode 6 to generate electrostatic induction, thereby outputting a periodic wear electrical signal between the electrodes. As the self-lubricating coating 7 wears, on the one hand, the coating thickness will change, affecting the electrostatic induction of the back electrode 6. On the other hand, a large amount of wear debris will be generated, resulting in a change in the net charge amount on the coating and the surface of the rotor 8. The combined effect of the two causes the open circuit voltage between the back electrodes 6 to change with the wear depth. The electrical signal analysis component can realize online monitoring of the coating wear depth by analyzing the changes in the electrical signal.

[0022] In addition, in addition to being able to monitor the coating wear depth online, the gas bearing coating wear detection device of the present application can also measure the rotor speed. Specifically, as the rotor rotates, the potential on the back electrode 6 changes periodically, thereby generating a periodic speed electrical signal. The output frequency of the electrical signal between the electrodes has a linear correlation with the rotor rotation frequency. Therefore, quantitative monitoring of the rotor speed can be achieved based on the frequency of the electrical signal.

[0023] It should be noted that traditional wear monitoring equipment cannot be applied due to the compact structure of the foil gas bearing. The present application directly integrates the back electrode 6 and the self-lubricating coating 7 on the inner surface of the bearing sleeve 2 based on the original structure of the foil gas bearing, and the conductive electrode sheet 1 is directly set on the outer surface of the rotor 8. That is, the detection device of the present application and the gas bearing structure are constructed as a whole, realizing the feasibility of online monitoring of the coating wear depth.

[0024] In the gas bearing coating wear detection device of the embodiment of the present invention, a conductive electrode sheet 1 is provided on the outer peripheral surface of the rotor 8, a bearing sleeve 2 is provided on the outer periphery of the rotor 8, and two back electrodes 6 are provided on the inner side of the bearing sleeve 2, and the surface of the back electrode 6 is covered with a self-lubricating coating 7. The two back electrodes 6 are connected to the electrical signal analysis component through wires to transmit wear electrical signals and speed electrical signals. Therefore, as the self-lubricating coating 7 wears, the open circuit voltage between the back electrodes 6 changes with the wear depth. The electrical signal analysis component can realize online monitoring of the coating wear depth by analyzing the changes in the wear electrical signal. At the same time, quantitative monitoring of the rotor speed can be realized based on the frequency of the speed electrical signal. In addition, since the conductive electrode sheet 1 and the back electrode 6 are directly integrated into the bearing, compared with the traditional wear detection device, the problem that the gas bearing structure is compact and the detection device cannot be applied is solved.

[0025] Furthermore, the gas bearing coating wear detection device of the present application can also determine wear failure. Specifically, when the self-lubricating coating is completely worn, the rotor contacts the back electrode. Due to the low amount of charge transferred between the metal materials, the potential difference between the back electrodes decreases significantly, almost to zero. Therefore, by monitoring the amplitude of the open-circuit voltage between the back electrodes to drop to zero, it is possible to detect coating wear failure.

[0026] Furthermore, a slot is provided on the surface of the rotor 8, into which the conductive electrode sheet 1 is embedded. Thus, the slot can hold the conductive electrode sheet 1, improving its assembly stability while not occupying additional space, thereby maintaining the original compactness of the gas bearing structure.

[0027] In other embodiments, the surface of the rotor 8 is coated with a conductive electrode sheet 1. Specifically, a micro-nanoscale conductive electrode sheet 1 can be prepared on the rotor surface by magnetron sputtering or other methods. The thickness of the conductive electrode sheet 1 can be only a few microns, which does not affect the compactness of the gas bearing.

[0028] Furthermore, the gas bearing coating wear detection device also includes a bump foil 3 and a top foil 4. The top foil 4 is disposed on the inner side of the bearing sleeve 2. The bump foil 3 is disposed on the inner circumference of the bearing sleeve 2 and is located between the top foil 4 and the bearing sleeve 2. The self-lubricating coating 7 is disposed on the inner side of the top foil 4 and covers the back electrode 6. It is understood that the bump foil 3 has a certain elastic buffering effect, which can prevent the rotor 8 and the bearing sleeve 2 from hard collision and wear. The top foil 4 provides an adhesion surface for the self-lubricating coating 7.

[0029] Furthermore, an insulating coating 5 is provided on the inner peripheral surface of the top foil 4, and the back electrode 6 is provided on the inner side of the insulating coating 5. The insulating coating 5 can insulate the inner surface of the top foil 4 to prevent the back electrode 6 from being conductive with the foil and to prevent the two independent back electrodes 6 from being conductive with each other.

[0030] Optionally, the insulating coating 5 is made of polyimide and has a thickness of 1-5 μm.

[0031] Optionally, there are a plurality of conductive electrode sheets 1 arranged at intervals in the circumferential direction of the rotor 8 .

[0032] Preferably, there are two conductive electrode sheets 1 , and the two conductive electrode sheets 1 are arranged on different sides of the rotor 8 in the radial direction of the rotor 8 .

[0033] Optionally, a plurality of back electrodes 6 are spaced apart in the axial direction of the bearing sleeve 2 .

[0034] Preferably, the back electrode 6 is a copper sheet.

[0035] Furthermore, the extension length of the back electrode 6 in the axial direction of the rotor 8 is L, and the axial length of the bearing sleeve 2 is L1, then the following is satisfied: 0.5L1≤L≤0.9L1. For example, L can be 0.5L1, 0.7L1, or 0.9L1.

[0036] Furthermore, the sector angle α of the back electrode 6 satisfies 20°≤α≤80°. For example, α may be 20°, 40°, 60°, or 80°.

[0037] Furthermore, the gap angle β between adjacent back electrodes 6 satisfies 10°≤β≤80°. For example, β may be 10°, 30°, 50°, 70° or 80°.

[0038] The gas bearing transmission system according to the embodiment of the present invention includes the gas bearing coating wear detection device according to the above embodiment.

[0039] The gas bearing transmission system of an embodiment of the present invention adopts the above-mentioned gas bearing coating wear detection device. A conductive electrode sheet 1 is provided on the outer peripheral surface of the rotor 8, a bearing sleeve 2 is provided on the outer periphery of the rotor 8, and two back electrodes 6 are provided on the inner side of the bearing sleeve 2. The surface of the back electrode 6 is covered with a self-lubricating coating 7. The two back electrodes 6 are connected to the electrical signal analysis component through a wire to transmit an electrical signal. Therefore, as the self-lubricating coating 7 wears, the open circuit voltage between the back electrodes 6 changes with the wear depth. The electrical signal analysis component can realize online monitoring of the coating wear depth by analyzing the changes in the electrical signal. At the same time, quantitative monitoring of the rotor speed can be realized based on the frequency of the electrical signal, which is convenient for controlling the operating status of the transmission system.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0042] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0043] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0044] In the present invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless they are mutually inconsistent.

[0045] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A gas bearing coating wear detection device, characterized in that: include: A rotor, wherein the outer circumference of the rotor is provided with conductive electrodes distributed in an array; A bearing sleeve, wherein the bearing sleeve is disposed on the outer periphery of the rotor, and the inner side of the bearing sleeve is coated with an insulating coating, and two back electrodes are disposed on the inner side of the insulating coating. The surface of the back electrodes is coated with a self-lubricating coating. At the initial start-up of the rotor, the conductive electrode sheet contacts and rubs against the self-lubricating coating, and the conductive electrode sheet can sweep across the area where the back electrodes are located as the rotor rotates; An electrical signal analysis component, wherein the two back electrodes are connected to the electrical signal analysis component through wires to transmit wear electrical signals and speed electrical signals. The electrical signal analysis component is used to infer the wear state of the self-lubricating coating based on the received wear electrical signals and to infer the rotor speed based on the received speed electrical signals.

2. The gas bearing coating wear detection device according to claim 1, characterized in that: The surface of the rotor is coated with the conductive electrode sheet, or a groove is provided on the surface of the rotor, and the conductive electrode sheet is embedded in the groove.

3. The gas bearing coating wear detection device according to claim 1, characterized in that: It also includes a corrugated foil and a top foil, wherein the top foil is arranged on the inner side of the bearing sleeve, the corrugated foil is arranged on the inner circumference of the bearing sleeve and is located between the top foil and the bearing sleeve, and the self-lubricating coating is arranged on the inner side of the top foil and covers the back electrode.

4. The gas bearing coating wear detection device according to claim 3, characterized in that: The insulating coating is provided on the inner circumferential surface of the top foil, and the back electrode sheet is provided on the inner side of the insulating coating.

5. The gas bearing coating wear detection device according to claim 1, characterized in that: The conductive electrode sheets are arranged in a plurality at intervals in the circumferential direction of the rotor.

6. The gas bearing coating wear detection device according to claim 5, characterized in that: There are two conductive electrode sheets, and the two conductive electrode sheets are arranged opposite to each other on different sides of the rotor in the radial direction of the rotor.

7. The gas bearing coating wear detection device according to claim 1, characterized in that: The back electrode is a copper sheet.

8. The gas bearing coating wear detection device according to claim 1, characterized in that: The extending length of the back electrode in the axial direction of the rotor is L, and the axial length of the bearing sleeve is L1, then the following condition is satisfied: 0.5L1≤L≤0.9L1.

9. The gas bearing coating wear detection device according to claim 1, characterized in that: The sector angle α of the back electrode satisfies 20°≤α≤80°, and the gap angle β between adjacent back electrodes satisfies 10°≤β≤80°.

10. A gas bearing transmission system, characterized in that: The invention comprises a gas bearing coating wear detection device according to any one of claims 1 to 9.

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