Intelligent air suspension bearing system

Abstract

The invention relates to the field of energy conversion, signal processing and feedback control, in particular to an intelligent air suspension bearing system. A main body comprises an air suspension bearing, a feedback control system, an air pump and a pipeline. The air floating bearing is composed of an outer ring and an inner ring, and the feedback control system is composed of a sensing unit and a processing-regulating unit. The sensing unit is composed of an insulating layer, an interdigital electrode layer and an electret layer, wherein the insulating layer and the interdigital electrode layer are sequentially attached to the inner surface of an outer ring of the air floating bearing, and the electret layer is attached to the outer surface of an inner ring of the air floating bearing. The processing-regulating unit is integrated on the side face of an outer ring of the air floating bearing through the micro-nano machining technology and is mainly composed of a battery, a single-chip microcomputer system and a relay. The air pump is connected with the air floating bearing outer ring through a pipeline, and the control end of the air pump is electrically connected with the processing-regulating unit. The interdigital electrode layer in the sensing unit is electrically connected with the processing-regulating unit; according to the intelligent air suspension bearing system, monitoring of the rotating speed and the running state of the air suspension bearing and self-correction of the deviation behavior are achieved.

Description

Technical Field

[0001] This invention relates to the fields of energy conversion, signal processing, and feedback control, and specifically to an intelligent air suspension bearing system. Background Technology

[0002] With the rapid development of industrial technology, non-contact bearings play a vital role in high-precision equipment, high-speed motors, aerospace, and other fields due to their characteristics of low friction, high speed, long life, and low or no lubrication. Currently, the most common non-contact bearings on the market are magnetic levitation bearings and air levitation bearings. Magnetic levitation bearings utilize magnetic force to achieve levitation and stable non-contact operation. Magnetic levitation bearing systems achieve positive feedback through sensors, controllers, and power amplifiers, making them more suitable for high-speed, high-precision, and high-power heavy-duty equipment. However, this bearing system has complex design and manufacturing technology, high cost, and requires a stable power supply during operation, resulting in high energy consumption. Air levitation bearings use gas as a lubricating medium, achieving non-contact operation by forming an air film between the shaft and the bearing. Currently, the vast majority of air levitation bearings on the market do not have feedback functionality, have lower cost, and are more suitable for medium- to low-power equipment. Therefore, designing an air levitation bearing system with feedback functionality has significant market value and application prospects.

[0003] Chinese invention patent CN202111129323.7 proposes a suspension state monitoring system and method for magnetic or air-suspended bearings. The system includes an integrated state data acquisition module, processing module, and display module. The state data acquisition module collects various state data such as bearing speed, temperature, and faults. After data processing, the display module presents the bearing's operating information to the user. This bearing monitoring system broadly describes a non-contact bearing state monitoring method without providing specific bearing state monitoring technology. Chinese invention patent CN202111385129.5 proposes an air-suspended bearing with an axial suspension self-correcting structure. This bearing has air inlets on self-correcting components located at both ends of the outer shaft assembly. By injecting gas of different pressures, a pressure difference is created to correct the position of the self-correcting components. The thrust of the self-correcting components then corrects the position of the outer shaft assembly, achieving feedback and automatic correction of the bearing state, resulting in better concentricity of the inner shaft rotation. However, this structure can only achieve axial correction of the air-bearing bearing, and its function is relatively simple. Summary of the Invention

[0004] This invention addresses the technical problem of existing air suspension bearings lacking self-sensing and feedback-correction functions by providing an intelligent air suspension bearing system. The main components include an air suspension bearing (hereinafter referred to as the air bearing), a feedback control system, an air pump, and piping. The air bearing consists of an outer ring and an inner ring. The feedback control system comprises a sensing unit and a processing-control unit. The sensing unit consists of an insulating layer, an interdigitated electrode layer sequentially attached to the inner surface of the outer ring of the air bearing, and an electret layer attached to the outer surface of the inner ring. The processing-control unit is integrated into the outer ring side of the air bearing using micro-nano fabrication technology and mainly consists of a battery, a microcontroller system, and a relay. The air pump is connected to the outer ring of the air bearing via piping, and its control terminal is electrically connected to the processing-control unit. The interdigitated electrode layer in the sensing unit is electrically connected to the processing-control unit. A schematic diagram of the overall structure of the intelligent air suspension bearing system provided by this invention is attached. Figure 1 The logical relationships between the units of the intelligent air suspension bearing system are shown in the appendix. Figure 2 .

[0005] Specifically, the air pump is connected to the outer ring of the air-floating bearing via a pipe. The pipes are evenly distributed on the outer ring of the bearing, and there are several (≥4) pipes. The pipe openings are equipped with air valve switches, which are electrically connected to the processing-control unit and controlled by the processing-control unit.

[0006] Specifically, the insulating layer attached to the inner surface of the outer ring of the air-bearing bearing is divided into two parts, left and right, with equal areas, to prevent the interdigitated electrode layer attached to its surface from conducting electricity with the outer ring body of the bearing; the interdigitated electrode layer is evenly attached to the surface of the insulating layer in two parts, left and right, with each part having an even number of interdigitated electrodes that are aligned; the interdigitated electrodes in the left and right parts are each divided into several equal groups (≥4), and the interdigitated electrodes in each group are electrically connected in series according to their odd or even numbers.

[0007] Specifically, the electret layer attached to the outer surface of the inner ring of the air-bearing bearing is distributed opposite to the left and right interdigitated electrode layers attached to the surface of the insulating layer, with each pair of interdigitated electrodes corresponding to one electret; the left and right electret layers are staggered. A partial enlarged view of the intelligent air-bearing bearing is attached. Figure 3 .

[0008] Specifically, the insulating layer, interdigitated electrode layer, and electret layer in the left and right parts of the sensing unit can be regarded as two sets of independent layered triboelectric nanogenerators (FTENGs), each FTENG comprising several sub-FTENGs. A schematic diagram of the planar unfolded insulating layer, electrode layer, and electret layer in the sensing unit is attached. Figure 4 See attached diagram for FTENG response signal output. Figure 5 .

[0009] Specifically, the pipelines are distributed in correspondence with the sub-FTENGs, and the number of pipelines is half the number of sub-FTENGs.

[0010] This invention provides an intelligent air-suspended bearing system that can monitor the rotational speed of the air-suspended bearing and its operating status, including radial and axial misalignment fault behaviors. It can also achieve self-correction of the bearing's misalignment behavior. The working principle of this intelligent air-suspended bearing system is as follows: When the air-suspended bearing rotates, the electret layer on the inner ring (rotor) and the interdigitated electrode layer on the outer ring (stator) undergo relative motion. Based on the principle of electrostatic induction, the sensing unit (two sets of FTENGs) generates a stable response electrical signal. The processing-control unit collects and processes this response electrical signal, and monitors the air-suspended bearing's rotational speed based on the frequency of the decoupled electrical signal. When the air-suspended bearing operates in a normal state (without any directional misalignment), the amplitudes of the output voltages of the two sets of FTENGs collected by the processing-control unit are equal. When the air-supported bearing shifts, the amplitude of the output voltage of the two sets of FTENGs changes, or the phase of the output voltage waveform changes, or the output amplitude of each set of sub-FTENGs changes. When the air-supported bearing shifts axially, taking the shift to the left (inner side in the 3D diagram) as an example, the area of ​​the electret layer and the interdigitated electrode facing each other decreases compared to when the air-supported bearing is working normally, and the output amplitude of both sets of FTENGs decreases significantly. The phase of the output voltage waveform of the right-side FTENG remains unchanged, while the phase of the output voltage waveform of the left-side FTENG gradually changes, and gradually increases with the increase of the air-supported bearing shift value. When the air-supported bearing shifts radially, that is, the inner and outer rings of the air-supported bearing are not concentric, the distance between the electret layer and the interdigitated electrode layer changes. At this time, the output phase of the two sets of FTENGs remains unchanged, but the output amplitude of each set of sub-FTENGs is no longer equal. The orientation of the sub-FTENG with the largest amplitude is the orientation of the air-supported bearing shift. The processing and control unit determines the motion state of the air-bearing bearing based on the output waveform characteristics of the two sets of FTENGs, and further adjusts the air pressure in a specific area through the corresponding control program to restore the air-bearing bearing to its normal working state.

[0011] Preferably, the insulating layer, electrode layer and electret layer are all prepared by 3D printing technology and then attached to the surface of the air bearing, and the thickness of each is controlled within 5-10 μm;

[0012] Preferably, the pipe opening connected to the outer ring of the bearing is located at the center of the left and right sub-FTENGs, and the air valve switch control line and the FTENG signal line have the same path and are both electrically connected to the processing-control unit.

[0013] Preferably, the microcontroller system in the processing-control unit is equipped with a high-frequency, multi-channel signal acquisition chip;

[0014] Preferably, the processing-control unit is miniaturized and integrated using EDA tools and then fixedly installed on the outer ring side of the air-bearing bearing.

[0015] Compared with the prior art, the distinguishing technical features and beneficial effects of the present invention are as follows:

[0016] This invention utilizes advanced triboelectric nanogenerator technology to convert the rotational behavior of an air-supported bearing into electrical signals. Based on the response signal characteristics of the nanogenerator, it enables the monitoring of the air-supported bearing's operating status, including speed monitoring and fault monitoring for axial and radial misalignment. Compared with existing air-supported bearing condition monitoring technologies, the air-supported bearing condition monitoring method provided by this invention is a self-powered monitoring method based on electromechanical energy conversion, offering a wider range of monitoring functions and lower costs.

[0017] This invention achieves accurate monitoring of the operating status of air-supported bearings based on the response signal characteristics of nanogenerators, and adjusts the air pressure in the fault area in real time according to the monitoring results, thus realizing self-correction of the air-supported bearing's misalignment behavior. Compared with existing air-supported bearing self-correction technologies, this invention has a wider range of correctable faults.

[0018] The intelligent air suspension bearing system provided by this invention realizes the monitoring of the rotational speed and operating status (including axial and radial offset) of the air suspension bearing, as well as the self-correction of offset behavior, which is expected to promote the research and development of low-cost, self-sensing, and self-correcting air suspension bearing systems. Attached Figure Description

[0019] Figure 1 A schematic diagram of the overall structure of the intelligent air suspension bearing system;

[0020] Figure 2 This is a logic diagram showing the inter-unit relationships of an intelligent air suspension bearing system.

[0021] Figure 3 Enlarged view of a portion of the intelligent air suspension bearing

[0022] Figure 4 This is a planar unfolded schematic diagram of the insulating layer, interdigitated electrode layer, and electret layer in the sensing unit;

[0023] Figure 5 Schematic diagram of FTENG response signal output

[0024] Among them, 1-air pump, 2-pipeline, 3-air suspension bearing, 4-feedback control system, 5-outer ring, 6-inner ring, 7-sensing unit, 8-processing-control unit, 9-insulating layer, 10-interdigital electrode layer, 11-electret layer. Detailed Implementation

[0025] To facilitate understanding of the technical solution of this invention, the specific implementation method of this invention is described in detail below with reference to the accompanying drawings. Taking a bearing outer ring with four pipes as an example, see the attached drawing. Figure 1-3This invention provides an intelligent air-bearing system comprising an air pump 1, a pipe 2, an air-bearing 3, a feedback control system 4, an outer ring 5, an inner ring 6, a sensing unit 7, a processing-control unit 8, an insulating layer 9, an interdigitated electrode layer 10, and an electret layer 11. The interdigitated electrode layer 10 and the electret layer 11 constitute an independent layered triboelectric nanogenerator (FTENG), with the left and right FTENG groups being 7-I and 7-II, respectively. In this embodiment, each FTENG group is divided into four sub-FTENGs: 7-I-1, 7-I-2, 7-I-3, 7-I-4 and 7-II-1, 7-II-2, 7-II-3, 7-II-4. When the intelligent air-bearing system is in operation, the air pump 1 pumps gas into the chamber of the air-bearing 3 through the pipe 2, and the air-bearing 3 and the feedback control system 4 enter the working state. The outer ring 5 and inner ring 6 rotate relative to each other. Correspondingly, the electret layer 11 located outside the inner ring 6 and the interdigitated electrode layer 10 located inside the outer ring 5 move relative to each other. The sensing unit 7 generates a response electrical signal, and the processing-control unit 8 collects and processes the electrical signal generated by the sensing unit 7, and further determines the working state of the air-floating bearing 3 based on the decoupled characteristic information, including frequency and amplitude. When the air-floating bearing 3 is operating normally, the area of ​​the electret layer 11 and the interdigitated electrode layer 10 facing each other is at its maximum, and the distance between them is equal everywhere. The output voltage amplitudes generated by the two sets of FTENG 7-I and 7-II in the sensing unit 7 are equal, and the waveform, period, and phase are stable. The rotational speed of the air-floating bearing 3 is obtained by decoupling the frequency of the output waveform. When the air-floating bearing 3 shifts axially, taking the shift to the left (inner side in the 3D diagram) as an example, the area of ​​the electret layer 11 and the interdigitated electrode layer 10 facing each other decreases. The output voltage amplitudes of the two sets of FTENGs 7-I and 7-II in the sensing unit 7 both decrease significantly. The output voltage waveform phase of the right FTENG group 7-II remains unchanged, while the output voltage waveform phase of the left FTENG group 7-I gradually changes, and gradually increases with the shift value of the air-floating bearing 3. When the air-floating bearing 3 shifts radially, the distance between the electret layer 11 and the interdigitated electrode layer 10 changes. At this time, the outer ring 5 and the inner ring 6 of the air-floating bearing 3 are not concentric circles. The output amplitudes of the sub-FTENGs 7-I-1, 7-I-2, 7-I-3, 7-I-4 and 7-II-1, 7-II-2, 7-II-3, 7-II-4 in the sensing unit 7 are no longer equal. The orientations of the two sub-FTENGs with the largest output amplitudes are the orientations of the radial shift of the air-floating bearing 3. The processing and control unit 8 determines the motion state of the air-bearing bearing based on the output waveform characteristics of the FTENG group in the sensing unit 7, and further adjusts the air pressure in a specific area through the corresponding control program to restore the air-bearing bearing to its normal working state.

[0026] In summary, the intelligent air suspension bearing system provided by this invention has functions such as bearing operation status monitoring (including speed monitoring, axial and radial offset fault behavior monitoring, and feedback-self-adjustment), which greatly improves the stability and production efficiency of equipment operation, reduces maintenance costs, and has broad prospects in precision machining and high-end medical equipment.

Claims

1. An intelligent air suspension bearing system, characterized in that, The intelligent air suspension bearing system includes an air suspension bearing, a feedback control system, an air pump, and pipelines. The air suspension bearing consists of an outer ring and an inner ring. The feedback control system consists of a sensing unit and a processing-control unit. The sensing unit consists of an insulating layer, an interdigitated electrode layer, and an electret layer attached sequentially to the inner surface of the outer ring of the air suspension bearing. The processing-control unit is integrated into the outer ring side of the air suspension bearing using micro-nano fabrication technology and mainly consists of a battery, a microcontroller system, and a relay. The air pump is connected to the outer ring of the air suspension bearing through pipelines, and the control terminal of the air pump is electrically connected to the processing-control unit. The interdigitated electrode layer in the sensing unit is also electrically connected to the processing-control unit.

2. The intelligent air suspension bearing system as described in claim 1, characterized in that, The air pump is connected to the outer ring of the air suspension bearing via a pipe. The pipes are evenly distributed on the outer ring of the bearing, with a quantity of ≥4. The pipe openings are equipped with air valve switches, which are electrically connected to and controlled by the processing-control unit.

3. The intelligent air suspension bearing system as described in claim 1, characterized in that, The insulating layer attached to the inner surface of the outer ring of the air suspension bearing is divided into two parts, left and right, with equal areas, to prevent the interdigitated electrode layer attached to its surface from conducting electricity with the outer ring body of the bearing. The interdigitated electrode layer is evenly attached to the surface of the insulating layer in two parts, left and right, with each part having an even number of interdigitated electrodes that are aligned. The interdigitated electrodes in the left and right parts are each divided into several groups of four or more, and the interdigitated electrodes in each group are electrically connected in series according to their odd or even numbers.

4. The intelligent air suspension bearing system as described in claim 1, characterized in that, The electret layer attached to the outer surface of the inner ring of the air suspension bearing is distributed opposite to the left and right interdigitated electrode layers attached to the surface of the insulating layer, with each pair of interdigitated electrodes corresponding to one electret; the left and right electret layers are distributed alternately.

5. The intelligent air suspension bearing system as described in claim 1, characterized in that, The insulating layer, interdigitated electrode layer and electret layer of the left and right parts of the sensing unit are regarded as two sets of independent layered triboelectric nanogenerators (FTENGs). Each FTENG set includes several sub-FTENGs. The channels are distributed in correspondence with the sub-FTENGs, and the number of channels is 1 / 2 of the number of sub-FTENGs.

6. The intelligent air suspension bearing system as described in claim 5, characterized in that, The pipe opening connected to the outer ring of the bearing is located at the center of the left and right sub-FTENGs. The air valve switch control line and the FTENG signal line have the same path and are both electrically connected to the processing-control unit.

7. The intelligent air suspension bearing system as described in claim 1, characterized in that, The insulating layer, electrode layer, and electret layer are all prepared using 3D printing technology and then attached to the surface of the air suspension bearing, with the thickness controlled within 5-10 μm.

8. The intelligent air suspension bearing system as described in claim 1, characterized in that, The microcontroller system in the processing-control unit is equipped with a high-frequency, multi-channel signal acquisition chip.

9. The intelligent air suspension bearing system as described in claim 1, characterized in that, The processing and control unit is miniaturized and fixedly installed on the outer ring side of the air suspension bearing after being miniaturized using EDA tools.

10. The intelligent air suspension bearing system as described in claim 1, characterized in that, When the air suspension bearing rotates, the electret layer on the inner ring of the bearing (which acts as the rotor) and the interdigitated electrode layer on the outer ring of the bearing (which acts as the stator) move relative to each other. Based on the principle of electrostatic induction, the sensing units, i.e., the two sets of FTENGs, generate stable response electrical signals. The processing and control unit collects and processes these response signals, and monitors the rotational speed of the air suspension bearing based on the frequency of the decoupled electrical signals. When the air suspension bearing is operating normally, i.e., without any directional deviation, the amplitudes of the output voltages from the two sets of FTENGs collected by the processing and control unit are equal. When the air suspension bearing deviates, the amplitudes of the output voltages from the two sets of FTENGs change, or the phase of the output voltage waveform changes, or the output amplitude of each sub-FTENG changes. The processing and control unit determines the motion state of the air suspension bearing based on the output waveform characteristics of the two sets of FTENGs, and further adjusts the air pressure in a specific area through a corresponding control program to restore the air suspension bearing to its normal operating state.

11. The intelligent air suspension bearing system as described in claim 10, characterized in that, When the air suspension bearing shifts axially, taking the shift to the left as an example, the area of ​​the electret layer and the interdigitated electrode facing each other decreases compared to when the air suspension bearing is working normally, and the output amplitude of both FTENGs decreases significantly. The output voltage waveform phase of the right FTENG remains unchanged, while the output voltage waveform phase of the left FTENG gradually changes, and gradually increases with the increase of the air suspension bearing shift value. When the air suspension bearing shifts radially, that is, the inner and outer rings of the air suspension bearing are not concentric, the distance between the electret layer and the interdigitated electrode layer changes. At this time, the output phase of the two FTENGs remains unchanged, but the output amplitude of each sub-FTENG is no longer equal. The orientation of the sub-FTENG with the largest amplitude is the orientation of the air suspension bearing shift.

Images