Aerodynamic gas thrust bearing based on a non-contacting rotary electrostatic generator and monitoring method

Abstract

The application discloses a kind of dynamic pressure gas thrust bearing based on non-contact rotary electrostatic generator and monitoring method, to solve the problem that bearing operating state parameter is difficult to measure, including static ring component and dynamic ring component, static ring component and dynamic ring component are arranged in parallel opposite;The static ring component includes bearing static ring, static ring insulating layer and static ring electrode layer, insulating layer is arranged between bearing static ring and static ring electrode layer, static ring electrode layer includes a plurality of first electrode and second electrode, first electrode and second electrode are staggered along the circumferential direction;The outer surface of first electrode and second electrode is each equipped with PET film layer, dynamic ring component includes metal electrode layer, dynamic ring insulating layer and bearing dynamic ring, dynamic ring insulating layer is arranged between bearing dynamic ring and metal electrode layer.The application combines triboelectric effect and gas bearing, realizes high speed, multi-parameter, in-situ monitoring by non-contact electrode design, solves the limitation of traditional method in closed environment, high-speed scene.The application relates to the technical field of bearing.

Description

Technical Field

[0001] This invention relates to the field of bearing technology, specifically to a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator and a monitoring method thereof. Background Technology

[0002] With the rapid development of aerospace, precision manufacturing, energy and chemical industries, the performance requirements for rotating machinery are constantly increasing, especially for equipment operating under high temperature, high speed, heavy load and harsh environmental conditions, which places even more stringent demands on lubrication systems. Therefore, research on gas machinery and gas dynamic lubrication is receiving increasing attention. Gas dynamic thrust bearings, due to their advantages of compact structure, high stability, low frictional torque and high load-bearing capacity, are widely used in small, high-speed, oil-free rotating machinery with operating speeds exceeding 100,000 rad / min, such as fuel cell air compressors, cryogenic turbine expanders and micro turbojet engines. However, because the gas film thickness of gas bearings is on the order of micrometers, parameters such as gas film clearance, bearing vibration, and rotational speed during operation are difficult to measure directly, posing a significant challenge to performance monitoring and optimization.

[0003] A non-contact rotary electrostatic generator is an energy harvesting device based on the principle of electrostatic induction. Its core feature lies in the fact that materials do not need to be in direct contact during power generation. It can be attached to bearing surfaces or embedded in narrow spaces, adapting to complex mechanical structures without affecting the original performance of the equipment, and achieving in-situ energy and information acquisition. Furthermore, because the gap between the two charged layers undergoes relative motion under external force, it changes the internal capacitance, thereby affecting the output voltage or current characteristics, which can be used to detect abnormal bearing conditions in real time.

[0004] This invention is based on the principle of a rotating electrostatic generator, which uses changes in capacitance to sense mechanical motion in order to solve the problem of the difficulty in measuring bearing operating parameters. Summary of the Invention

[0005] This invention is based on the principle of a rotating electrostatic generator. It uses capacitance to highly sense minute mechanical movements in the bearing's operating state, thereby solving the problem of the difficulty in measuring bearing operating state parameters. Furthermore, it proposes a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator and a monitoring method thereon.

[0006] The technical solution adopted by the present invention to solve the above problems is as follows: This invention proposes a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator, comprising a stationary ring assembly and a rotating ring assembly, wherein the stationary ring assembly and the rotating ring assembly are arranged parallel to each other; the stationary ring assembly includes a bearing stationary ring, a stationary ring insulating layer, and a stationary ring electrode layer, with an insulating layer provided between the bearing stationary ring and the stationary ring electrode layer; the stationary ring electrode layer includes a plurality of first electrodes and second electrodes, which are staggered along the circumferential direction; the outer surfaces of the first electrodes and the second electrodes are each provided with a PET film layer; the rotating ring assembly includes a metal electrode layer, a rotating ring insulating layer, and a bearing rotating ring, with a rotating ring insulating layer provided between the bearing rotating ring and the metal electrode layer.

[0007] Furthermore, the bearing stationary ring is provided with a groove that matches the size of the stationary ring insulation layer, and the insulation layer is fixed to the groove of the bearing stationary ring by adhesive bonding.

[0008] Furthermore, the first electrode and the second electrode are arranged in a complementary fan shape and are stacked on the surface of the insulating layer by bonding.

[0009] Furthermore, the bearing moving ring is provided with a groove that matches the size of the moving ring insulation layer. The moving ring insulation layer is installed in the groove of the bearing moving ring. The metal electrode layer consists of multiple fan-shaped electrodes arranged in a ring array and fixed to the surface of the insulation layer by adhesive bonding.

[0010] Furthermore, the metal electrode layer is parallel to the stationary ring electrode layer, and the distance between the metal electrode layer and the stationary ring electrode layer is equal to the gas film thickness. .

[0011] This invention proposes a monitoring method for a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator, comprising the following steps: Step 1: System installation and initialization; The stationary ring assembly is fixed to the stator end face of the bearing, and the first and second electrodes, which have PET film layers, are aligned with the air film region of the bearing; the rotating ring assembly is installed on the rotor end face of the bearing, with the metal electrode layer parallel to the stationary ring electrode layer and the spacing between them equal to the air film thickness. Connect the first and second electrodes of the bearing stationary ring with a high-resistance resistor, and connect the two ends of the resistor with an electrometer to measure the open-circuit voltage. ; Step 2: Open-circuit voltage signal acquisition and processing; Start the bearing to make the rotor reach the target speed. Rotate to collect open-circuit voltage The time-domain signal is obtained, and the signal is bandpass filtered to extract the electrostatic induction characteristic waveform; Step 3: Calculate the bearing speed ; From the filtered open-circuit voltage Extract signal period According to the number of static ring electrode layers Calculate the rotational speed :

[0012] Step 4: Air film thickness Inversion: Extracting open-circuit voltage amplitude Calculate the air film thickness based on the calibration relationship. :

[0013] in For system constants, ; Step 5: Bearing condition diagnosis; Real-time monitoring of bearing speed and air film thickness The fluctuations, combined with spectral characteristics, are analyzed to determine if bearing rubbing or vibration is abnormal.

[0014] Furthermore, in step 5, when the rotational speed... Or air film thickness If the threshold is exceeded, the bearing is deemed to be at risk of instability or film rupture.

[0015] The beneficial effects of this invention are: 1. In-situ sensing and monitoring: Traditional measurement methods, such as laser interferometers, are limited by the optical window and cannot be used inside enclosed bearings. This invention embeds the stationary ring electrode into the bearing end face, and the moving ring metal electrode is directly integrated into the rotor, requiring zero additional space. 2. Dynamic response advantage: The capacitance change rate and rotational speed of this invention are related. Synchronous monitoring supports ultra-high-speed real-time monitoring at speeds of 20,000 to 30,000 rad / min. 3. Multi-parameter synchronous monitoring capability: This invention monitors multiple parameters simultaneously from a single signal source (open circuit voltage). Simultaneous analysis of three key parameters—air film thickness, rotational speed, and bearing vibration—significantly reduces system complexity and cost. 4. This invention combines triboelectric effect with gas bearings and achieves high-speed, multi-parameter, in-situ monitoring through non-contact electrode design, overcoming the limitations of traditional methods in closed environments and high-speed scenarios. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator according to the present invention. Figure 2 This is a schematic diagram of the static ring assembly of the present invention; Figure 3 This is a schematic diagram of the structure of the dynamic ring assembly of the present invention; Figure 4 This is a graph showing the open-circuit output characteristics of the non-contact triboelectric generator of the present invention. Figure 5 This is a graph showing the relationship between the open-circuit voltage and the gas film thickness of the non-contact triboelectric generator of the present invention. Figure 6 This is a schematic diagram illustrating the operating principle of a non-contact rotating electrostatic generator. Figure 7 This is the equivalent circuit diagram of a non-contact rotating electrostatic generator. Figure 8 This refers to the working cycle of a non-contact triboelectric generator.

[0017] In the diagram: 1-Bearing stationary ring; 2-Stationary ring insulation layer; 3-First electrode; 4-Second electrode; 5-Metal electrode layer; 6-Moving ring insulation layer; 7-Bearing moving ring. Detailed Implementation

[0018] Specific Implementation Method 1: This implementation method describes a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator, such as... Figure 1 As shown, it includes a stationary ring assembly and a rotating ring assembly, wherein the stationary ring assembly and the rotating ring assembly are arranged in parallel and opposite to each other; like Figure 2 As shown, the stationary ring assembly includes a bearing stationary ring 1, a stationary ring insulating layer 2, and a stationary ring electrode layer. An insulating layer 2 is provided between the bearing stationary ring 1 and the stationary ring electrode layer. The stationary ring electrode layer includes a plurality of first electrodes 3 and second electrodes 4, which are staggered along the circumferential direction. A PET film layer is provided on the outer surface of both the first electrodes 3 and the second electrodes 4.

[0019] In some embodiments, the bearing stationary ring 1 is provided with a groove that matches the size of the stationary ring insulation layer 2, and the insulation layer 2 is fixed in the groove of the bearing stationary ring 1 by adhesive bonding.

[0020] In some embodiments, the first electrode 3 and the second electrode 4 are arranged in a complementary fan shape and are laminated on the surface of the insulating layer 2 by adhesive bonding.

[0021] like Figure 3 As shown, the moving ring assembly includes a metal electrode layer 5, a moving ring insulating layer 6, and a bearing moving ring 7, with the moving ring insulating layer 6 provided between the bearing moving ring 7 and the metal electrode layer 5.

[0022] In some embodiments, the bearing moving ring 7 is provided with a groove that matches the size of the moving ring insulating layer 6, the moving ring insulating layer 6 is installed in the groove of the bearing moving ring 7, and the metal electrode layer 5 consists of a plurality of fan-shaped electrodes arranged in a ring array and fixed to the surface of the insulating layer 6 by adhesive bonding.

[0023] The metal electrode layer 5 is parallel to the stationary ring electrode layer, and the distance between the metal electrode layer 5 and the stationary ring electrode layer is equal to the gas film thickness. .

[0024] Specific Implementation Method Two: The monitoring method for a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator described in this implementation method includes the following steps: Step 1: System Installation and Initialization Use static ring components (such as Figure 2 (As shown) is fixed to the end face of the bearing stator, ensuring that the first electrode 3 and the second electrode 4, which cover the PET film, are aligned with the bearing gas film region. The moving ring assembly (such as...) is then... Figure 3 (As shown) Installed on the end face of the bearing rotor, the metal electrode layer 5 is parallel to the stationary ring electrode layer, with a spacing equal to the gas film thickness. Connect the first electrode 3 and the second electrode 4 of the stationary ring with a high-resistance resistor, and connect the two ends of the resistor through an electrometer to measure the open-circuit voltage. .

[0025] Step 2: Open-circuit voltage signal acquisition and processing: Start the bearing to make the rotor reach the target speed. Rotate. Collect open-circuit voltage. The time-domain signal is obtained, and bandpass filtering is performed on the signal (to remove power frequency and mechanical vibration noise), and electrostatic induction characteristic waveforms (such as...) are extracted. Figure 4 (As shown).

[0026] Step 3, Bearing Speed calculate: From the filtered Extract signal period (i.e., the interval between adjacent voltage peaks). Based on the number of stationary loop electrode pairs. ( Figure 2 (Calculate the rotational speed by taking the logarithm of the first electrode 3 and the second electrode 4). :

[0027] Step 4: Air Film Thickness Inversion: Extracting open-circuit voltage amplitude ( Figure 5 (Vertical axis). Calculate the film thickness based on the calibration relationship. :

[0028] in For system constants,

[0029] Step 5: Bearing Condition Diagnosis Real-time monitoring of bearing speed and air film thickness Fluctuations: When Threshold, rotor instability; when Threshold, risk of air film rupture. Analysis. The spectral characteristics (such as harmonic distortion rate) are used to detect bearing rubbing or vibration abnormalities.

[0030] The principle of this invention is as follows Figure 6 As shown: A non-contact rotating electrostatic generator consists of a rotating ring and a stationary ring. The upper rotating ring is made of a belt. The system consists of metal electrodes carrying charges, with the lower stationary ring composed of two copper electrodes of complementary shapes and a PET film. When the moving ring rotates, electrostatically induced charges transfer between electrodes A and B. Simultaneously, capacitance is formed between the metal electrodes and between copper electrode 1 and copper electrode 2. , As the metal electrode rotates , Things will also change.

[0031] like Figure 7 The diagram shows the equivalent circuit of a non-contact rotating electrostatic generator. According to Kirchhoff's current law, the voltage at node 1 is assumed to be... ,get: (1) (2) (3) like Figure 8 The diagram illustrates several stages that a triboelectric generator goes through in one cycle, ignoring the gap between electrode 1 and electrode 2. Assume a) is the initial stage, with the metal electrode located at the center of electrode 1 and electrode 2. The angle between the projected areas of the metal electrode and electrode 1 at this stage is... As the moving ring rotates, the projected area between the metal electrode and electrode 2 gradually increases, while the projected area between the metal electrode and electrode 1 gradually decreases. When the metal electrode and electrode 2 completely overlap, Increase to the maximum value , a) The projected area between the metal electrode and electrode 2 gradually decreases, while the projected area between the metal electrode and electrode 1 gradually increases; b) The projected area between the metal electrode and electrode 1 gradually decreases, while the projected area between the metal electrode and electrode 2 gradually increases; c) The projected area between the metal electrode and electrode 1 gradually decreases, while the projected area between the metal electrode and electrode 2 gradually increases; d) The metal electrode returns to its initial position.

[0032] When the metal electrode completely overlaps with electrode 1 or electrode 2, ignoring edge effects, the maximum capacitance is achieved.

[0033] (4) In the formula: It is the vacuum dielectric constant. F / m; It is the relative permittivity of PET , It is the relative permittivity of air. ; It is the overlapping area of ​​the projected surfaces between two parallel plates. ; (5) In the formula: It is the thickness of the PET film, It is the thickness of the air layer between the metal electrode and the PET. Substituting into equation (4), we get: Assume the metal electrode layer of the rotating electrostatic generator rotates at a uniform speed of v. For capacitors have: (6) For capacitors have: (7) Solve equations (1), (2), and (3): (8) (9) in Then equation (9) is: (10) (11) It is a constant related to the initial conditions and can be represented by equation (12): (12) Substituting equations (11) and (12) into equation (1) yields the voltage. Differential equation: (13) (14) The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments without departing from the scope of the present invention, based on the technical essence of the present invention and within the spirit and principles of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator, characterized in that: It includes a stationary ring assembly and a rotating ring assembly, wherein the stationary ring assembly and the rotating ring assembly are arranged in parallel and opposite to each other; The stationary ring assembly includes a bearing stationary ring (1), a stationary ring insulating layer (2), and a stationary ring electrode layer. The stationary ring insulating layer (2) is provided between the bearing stationary ring (1) and the stationary ring electrode layer. The stationary ring electrode layer includes multiple first electrodes (3) and second electrodes (4), which are staggered along the circumferential direction. The first electrodes (3) and second electrodes (4) are arranged in a complementary fan shape. The outer surfaces of the first electrodes (3) and second electrodes (4) are both provided with a PET film layer. The moving ring assembly includes a metal electrode layer (5), a moving ring insulation layer (6), and a bearing moving ring (7). The moving ring insulation layer (6) is provided between the bearing moving ring (7) and the metal electrode layer (5). The metal electrode layer (5) consists of multiple fan-shaped electrodes arranged in a ring array. The metal electrode layer (5) is parallel to the stationary ring electrode layer, and the distance between the metal electrode layer (5) and the stationary ring electrode layer is equal to the gas film thickness. The stationary ring assembly is fixed to the end face of the bearing stationary ring, and the first electrode (3) and the second electrode (4) with PET film layer are aligned with the bearing air film area; the moving ring assembly is installed on the end face of the bearing rotor; a high resistance resistor is connected to the first electrode (3) and the second electrode (4) of the bearing stationary ring (1), and the open circuit voltage is measured by connecting the two ends of the resistor through an electrometer.

2. The dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator according to claim 1, characterized in that: The bearing stationary ring (1) is provided with a groove that matches the size of the stationary ring insulation layer (2), and the stationary ring insulation layer (2) is fixed in the groove of the bearing stationary ring (1) by adhesive bonding.

3. The dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator according to claim 1, characterized in that: The first electrode (3) and the second electrode (4) are laminated on the surface of the static ring insulating layer (2) by bonding.

4. The dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator according to claim 1, characterized in that: The bearing moving ring (7) is provided with a groove that matches the size of the moving ring insulation layer (6). The moving ring insulation layer (6) is installed in the groove of the bearing moving ring (7) and is fixed to the surface of the moving ring insulation layer (6) by adhesive bonding.

5. A method for monitoring the dynamic pressure gas thrust bearing of a non-contact rotating electrostatic generator according to any one of claims 1 to 4, comprising the following steps: Step 1: System installation and initialization; The stationary ring assembly is fixed to the end face of the bearing stator. The first electrode (3) and the second electrode (4) with PET film layers are aligned with the bearing gas film region. The first electrode (3) and the second electrode (4) are arranged in a complementary fan shape. The moving ring assembly is installed on the end face of the bearing rotor. The metal electrode layer (5) consists of multiple fan-shaped electrodes arranged in a ring array. The metal electrode layer (5) is parallel to the stationary ring electrode layer, and the spacing is equal to the gas film thickness. Connect the first electrode (3) and the second electrode (4) of the bearing stationary ring (1) with a high-resistance resistor, and measure the open-circuit voltage by connecting the two ends of the resistor with an electrometer. ; Step 2: Open-circuit voltage signal acquisition and processing; Start the bearing to make the rotor reach the target speed. Rotate to collect open-circuit voltage The time-domain signal is obtained, and the signal is bandpass filtered to extract the electrostatic induction characteristic waveform; Step 3: Calculate the bearing speed ; From the filtered open-circuit voltage Extract signal period According to the number of static ring electrode layers Calculate the rotational speed : Step 4: Air film thickness Inversion: Extracting open-circuit voltage amplitude Calculate the air film thickness based on the calibration relationship. : in For system constants, ; Step 5: Bearing condition diagnosis; Real-time monitoring of bearing speed and air film thickness The fluctuations, combined with spectral characteristics, are analyzed to determine if bearing rubbing or vibration is abnormal.

6. The monitoring method for a dynamic pressure gas thrust bearing based on a non-contact rotating electrostatic generator according to claim 5, wherein in step 5, when the rotational speed... Or air film thickness If the threshold is exceeded, the bearing is deemed to be at risk of instability or film rupture.

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