Friction pair lubrication state monitoring device and method under fluid lubrication condition based on TENG

Abstract

The invention relates to the technical field of TENG, in particular to a device and method for monitoring the lubrication state of a friction pair under the fluid lubrication condition based on TENG, and the device comprises a bearing which comprises an inner ring, an outer ring, a rolling body and a sealing ring, the outer ring is fixed in a center hole of a base, and the inner ring is provided with a stop screw hole for locking; the oil injection port is used for injecting lubricating oil into the bearing; one end of the wire is fixed on the inner ring, and the other end of the wire is connected to the electrometer to form a friction nano generator (TENG); the electrometer is used for detecting and outputting a current signal caused by the change of the friction state; the computer is connected with the electrometer and is used for receiving and analyzing the current signal; the base is used for bearing and fixing the bearing, mounting holes for mounting are formed in the base, mounting holes are symmetrically formed in the two sides of the base, and the base is fixed through bolts; the lubricating state is monitored based on the change of the electric signal generated by the change of the friction state of the TENG.

Description

Technical Field

[0001] The present invention relates to the field of TENG technology, and in particular to a device and method for monitoring the lubrication state of a friction pair under fluid lubrication conditions based on TENG. Background Art

[0002] Sealing devices are widely used in mechanical equipment. They can effectively prevent the leakage of lubricating substances and prevent external dust and impurities from entering the equipment, thereby damaging the operation of the mechanical device. Sealing devices can be found in the automotive, aerospace, medical equipment, mechanical processing and other industries. It plays a vital role in ensuring the normal operation of the equipment and improving production efficiency. The lubrication state of the sealing device is one of the most important factors affecting the normal operation of the sealing device. The lubrication state of the device will be affected if it is in complex working conditions (high temperature, high pressure, etc.) for a long time. By monitoring the lubrication state, the wear of the equipment can be reduced, the service life can be extended, and the production efficiency can be improved. Therefore, it is particularly important to monitor the lubrication state of the sealing device in real time.

[0003] TENG is a technology that converts mechanical energy into electrical energy. It uses the friction electrification effect between different materials to generate charge and generate current. The present invention will monitor the lubrication state of the sealing device based on TENG technology. Compared with other detection technologies, sensor monitoring can only monitor a single characteristic (pressure, temperature, flow, etc.), and cannot fully and accurately reflect the lubrication state. Vibration monitoring is easily affected by external factors. TENG detection technology can reflect the lubrication state of the sealing device in real time, comprehensively and not easily affected. The feasibility of the present invention is mainly demonstrated by monitoring the lubrication state of the vertical bearing seat through the following example.

[0004] A vertical bearing seat is a mechanical component used to support and fix bearings. It is often used in various fields. However, when working, the air often contains tiny particles such as dust and sand. If there is a lack of sealing, these impurities can easily enter the interior of the bearing. They will cause wear between the rolling elements and the inner and outer rings of the bearing, make the inner surface of the bearing rough, and reduce the accuracy and service life of the bearing. For example, in dusty environments such as mines and construction sites, the importance of sealing is particularly prominent. Secondly, lubricants are often required during work to reduce friction and wear. If there is a lack of sealing, lubricants may leak out from the inside of the bearing. This will not only cause a waste of lubricant, but also cause the bearing to lose sufficient lubrication, resulting in increased friction and temperature, which will accelerate the damage of the bearing. For example, in high-speed mechanical equipment, lubricant leakage may cause serious failures, so seals are used for bearings.

[0005] However, the lubricating oil in the bearing will deteriorate over time, and will be consumed as the speed increases and the temperature rises. When the lubricating oil is reduced to a certain extent, it will cause severe friction between the inner surface of the bearing and the rolling element. Moreover, when the sealed bearing is disassembled, if the operation is improper, the sealing ring may be deformed and damaged. When the inspection is completed and the second installation is performed, it may not be possible to accurately adjust the centering, thereby affecting the working performance of the bearing seat. The difficulty in disassembling the bearing seat makes it impossible for us to timely and accurately understand the operating status of the bearing and whether it is in a state of friction and wear. Therefore, the present invention monitors the friction and wear conditions of the bearing by the different current values ​​generated under different friction states, so that we can understand the operating conditions of the bearing more conveniently and timely.

[0006] In order to solve the above-mentioned bearing problem, the present invention proposes a friction pair lubrication state monitoring device under fluid lubrication conditions based on TENG, which uses the current value generated under different friction states to determine whether the bearing is in a normal lubrication state. The present invention can completely avoid the above-mentioned shortcomings and detect the lubrication state of the bearing without disassembling the bearing. Summary of the invention

[0007] The purpose of the present invention is to provide a friction pair lubrication state monitoring device under fluid lubrication conditions based on TENG, monitor the lubrication state of the sealing device through the detection technology of TENG, and reasonably design the TENG structure for different sealing devices and integrate it into the friction part of the sealing device. The change of the friction state generates the change of the electrical signal to monitor the lubrication state.

[0008] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0009] A friction pair lubrication state monitoring device under fluid lubrication conditions based on TENG, comprising:

[0010] The bearing comprises an inner ring, an outer ring, a rolling element and a sealing ring, wherein the outer ring is fixed in the center hole of the base, and the inner ring is provided with a stop screw hole for locking;

[0011] An oil filling port, used for injecting lubricating oil into the bearing;

[0012] A wire, one end of which is fixed to the inner ring and the other end is connected to an electrometer to form a triboelectric nanogenerator (TENG);

[0013] An electrometer, used to detect and output a current signal caused by a change in the friction state;

[0014] a computer, connected to the electrometer, for receiving and analyzing the current signal;

[0015] The base is used to carry and fix the bearing, and is provided with mounting holes for installation. The mounting holes are symmetrically arranged on both sides, and the base is fixed by bolts.

[0016] Furthermore, the bearing includes an inner ring, an outer ring, rolling elements and a sealing ring. The outer ring is fixed in the center hole of the base, and the thickness of the inner ring is greater than that of the outer ring. One side of the inner ring is flush with the outer ring, and the other side protrudes from the outer ring. The inner ring is provided with a set screw hole to ensure effective locking of the bearing and the shaft to provide stable support when the equipment is running.

[0017] Furthermore, the sealing ring is installed between the inner ring and the outer ring of the bearing to prevent external dust and debris from entering the interior of the bearing.

[0018] Furthermore, the oil filling port is arranged on the outer ring of the bearing, and is used to inject lubricating oil into the interior of the bearing to ensure that the rolling elements between the inner and outer rings are well lubricated.

[0019] Furthermore, one end of the wire is fixed to the inner ring through the oil filling port, and the other end is connected to the electrometer, ensuring that when the lubricating oil is consumed and the friction state changes, the wire can effectively transmit the electrical signal generated by the TENG.

[0020] This design is a non-invasive test: it can be tested to determine the lubrication status without disassembling the equipment. It has high sensitivity: the phenomenon of friction charging can be seen at the early stage of lubrication failure. It is suitable for a wide range of environments: the phenomenon of friction charging can occur in high temperature, low temperature, humid and other environments.

[0021] TENG's working modes are mainly divided into four types: vertical contact-separation mode, horizontal sliding mode, single electrode mode and independent layer mode. This design is based on the horizontal sliding mode. When two different materials (the inner and outer rings of the bearing and the rolling element in this design) slide relative to each other on a plane to generate charge transfer, due to their different electrophilic abilities, electrons will be transferred from one material to another, so that the inner and outer rings of the bearing and the rolling element surface will carry opposite charges. Electrons will transfer between materials, causing the inner and outer rings of the bearing and the rolling element to carry opposite charges, and then form a current through electrostatic induction. The electrical signal is displayed on the computer through the connected wires and electrometer, thereby judging the lubrication status of the bearing.

[0022] On the other hand, the present invention proposes a lubrication state monitoring method based on the above device, comprising the following steps:

[0023] S1: Select TENG components suitable for the bearing to be monitored, including bearings, wires, electrometers, etc. Fix one end of the wire to the inner ring of the bearing and connect the other end to the electrometer to detect the electrical signal caused by friction changes; inject appropriate lubricating oil through the oil filling port of the bearing to ensure good initial lubrication.

[0024] S2: Under static or normal working conditions, record the initial current signal generated by TENG to establish the baseline electrical signal of the bearing in a good lubrication state. Compare the good lubrication state with different degradation or fault states (such as lack of oil, excessive friction, etc.), and establish the corresponding electrical signal feature library as a reference for subsequent monitoring.

[0025] S3: During the operation of the equipment, the electrometer continuously collects the electrical signals transmitted by the wire. Since the change of friction state will cause the change of the output current characteristics of TENG, an electrometer is needed to capture these subtle changes; the collected current signal is transmitted to the computer, and the signal is processed and analyzed using special software. By comparing with the characteristic signal library, the current lubrication state is judged.

[0026] S4: When the current signal deviates from the initial state or the normal range in the characteristic signal library, the system automatically determines that the bearing lubrication state is poor, and there may be problems such as increased friction and wear or insufficient lubricant. Once an abnormal signal is detected, the system will generate an early warning prompt and notify the maintenance personnel through a computer display or other alarm system. According to the type of problem detected, specific maintenance suggestions are given, such as adding lubricant, checking the integrity of the seal ring, or replacing bearing components.

[0027] S5: Record all monitoring data and maintenance operations, and conduct trend analysis to optimize equipment operation and maintenance strategies; continuously update the feature signal library and monitoring algorithm based on actual operation conditions to improve signal recognition accuracy and false alarm rate.

[0028] Beneficial effects of the present invention:

[0029] The present invention uses a friction nanogenerator to capture subtle changes in the lubrication state of the bearing friction pair surface. TENG converts mechanical energy into electrical energy based on electrostatic induction and triboelectric effects, and this process has extremely high sensitivity. When the friction state changes (such as lubricant depletion or increased friction), the characteristics of the electrical signal such as frequency and amplitude change accordingly. This enables the monitoring system to capture tiny changes in the lubrication state and reflect them in the output signal in real time, accurately judging the current lubrication state. This high-precision monitoring capability is superior to traditional sensors and can respond to problems as soon as they occur to avoid further damage.

[0030] The design of the present invention allows online monitoring of the bearing without stopping or disassembling the equipment for inspection, greatly improving production efficiency. At the same time, it avoids damage to the bearing base or bearing during disassembly; one end of the wire is fixed to the inner ring, and the other end is connected to the external electrometer and computer to quickly transmit the TENG signal to the outside. This design eliminates the need for disassembly in traditional methods, avoids potential damage to the seal ring and precision loss caused by disassembly. In addition, online monitoring reduces downtime and the need for manual inspection, improving equipment availability and production efficiency.

[0031] The system can instantly identify changes in lubrication status by processing the collected electrical signals in real time through computer analysis software. The system automatically generates an alarm message if a signal deviating from the normal range is detected by comparing it with the established electrical signal reference library. This intelligent early warning function can quickly remind maintenance personnel to take intervention measures, such as adding lubricant or checking seal integrity, to prevent potential failures. The real-time feedback and early warning mechanism significantly improves the initiative of maintenance and the safety of equipment operation.

[0032] The TENG monitoring device of the present invention has a simple structure and strong adaptability. It can operate stably in different harsh working environments through the setting of the sealing ring. Since it does not rely on an external power supply and has no special requirements for catering to complex environmental conditions, the TENG device can be used normally in high temperature, high pressure or dusty environments, which helps to improve the overall stability of the equipment. In addition, the monitoring data recorded and analyzed by the system is used to optimize the maintenance strategy, identify the patterns of equipment wear and lubrication status changes through trend analysis, and customize the maintenance plan. This not only reduces the false alarm rate, but also effectively extends the service life of the equipment, reduces unnecessary downtime maintenance, and improves the overall economic benefits.

[0033] In view of the fact that existing technologies have insufficient real-time monitoring capabilities, poor environmental adaptability, limited early fault detection capabilities, and high maintenance costs, this design uses a triboelectric nanogenerator (TENG) to detect the lubrication status of the bearing and largely solves the limitations of traditional detection technology.

[0034] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0036] Figure 1 It is a structural schematic diagram of the vertical bearing seat of the present invention;

[0037] Figure 2 It is a schematic cross-sectional structure diagram of a vertical bearing seat of the present invention;

[0038] Figure 3 It is a schematic diagram of the bearing base of the present invention;

[0039] Figure 4 A schematic diagram of a bearing according to the present invention;

[0040] In the figure: 1. data acquisition card, 2. electrometer, 3. bearing, 4. computer, 5. inner ring, 6. rolling element, 7. sealing ring, 8. oil filling port, 9. wire, 10. oil filling port, 11. base, 12. outer ring, 13. stop screw hole, 14. center hole, 15. mounting hole. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Example 1

[0043] The present embodiment provides a method for monitoring the lubrication state of a surface-to-surface friction pair under fluid lubrication conditions based on TENG, comprising the following steps:

[0044] S1: Select TENG components suitable for the bearing to be monitored, including bearings, wires, electrometers, etc. Fix one end of the wire to the inner ring of the bearing and connect the other end to the electrometer to detect the electrical signal caused by friction changes; inject appropriate lubricating oil through the oil filling port of the bearing to ensure good initial lubrication.

[0045] S2: Under static or normal working conditions, record the initial current signal generated by TENG to establish the baseline electrical signal of the bearing in a good lubrication state. Compare the good lubrication state with different degradation or fault states (such as lack of oil, excessive friction, etc.), and establish the corresponding electrical signal feature library as a reference for subsequent monitoring.

[0046] S3: During the operation of the equipment, the electrometer continuously collects the current signal transmitted by the wire. Since the change of friction state will cause the change of the output current characteristics of TENG, high-precision acquisition equipment is required to capture these subtle changes; the collected current signal is transmitted to the computer, and the signal is processed and analyzed using special software. By comparing with the characteristic signal library, the current lubrication state is judged.

[0047] S4: When the current signal deviates from the initial state or the normal range in the characteristic signal library, the system automatically determines that the bearing lubrication state is poor, and there may be problems such as increased friction and wear or insufficient lubricant. Once an abnormal signal is detected, the system will generate an early warning prompt and notify the maintenance personnel through a computer display or other alarm system. According to the type of problem detected, specific maintenance suggestions are given, such as adding lubricant, checking the integrity of the seal ring, or replacing bearing components.

[0048] S5: Record all monitoring data and maintenance operations, and conduct trend analysis to optimize equipment operation and maintenance strategies; continuously update the feature signal library and monitoring algorithm based on actual operation conditions to improve signal recognition accuracy and false alarm rate.

[0049] In this embodiment, the step S1 specifically includes:

[0050] 1. TENG component selection:

[0051] Bearing: Choose UCP204 bearing, with a rated load of 12.7kN and a maximum speed of 6500r / min. When selecting bearings, the load requirements and operating speed of the equipment should be taken as the basis to ensure that they operate within their specifications to extend their service life.

[0052] Conductor: Choose copper conductor, length 1.5 meters, cross-sectional area 0.5 square millimeters, resistivity 1.68×10 -8 Ω·m. The resistance calculation example is R=1.68×10 -8 ×(1.5 / 0.5×10 -6 )=0.05Ω, ensuring low impedance transmission of signals.

[0053] Electrometer: The Kistler 5073A electrometer was selected, with a detection limit of 0.1pA. Its sensitivity was ensured to be able to capture the current signal generated by the TENG when the friction changes slightly.

[0054] 2. Wire fixing:

[0055] Fix the wire to the inner ring of the bearing with high temperature resistant (at least 180℃) epoxy resin glue to ensure that it does not loosen. The fixing point is located on the upper part of the inner ring to avoid affecting normal rotation.

[0056] In the connection step, the other end of the wire is connected to the electrometer by welding. The welding current is 50A short-time pulse to ensure that the contact resistance is less than 0.01Ω to ensure that the signal is transmitted without attenuation.

[0057] 3. Lubricant injection

[0058] Choose to use ISO VG32 grade lubricant, whose dynamic viscosity is 32cSt (centistoke) at 40°C. Under working conditions, choose lubricant with appropriate viscosity according to the specific operating temperature to ensure the formation of oil film.

[0059] The amount of lubricating oil is based on 1 / 3 of the internal volume of the bearing. If the inner diameter of the bearing is 20 mm, the outer diameter is 47 mm, and the width is 14 mm, then the volume V = π / 4 × (47 2 -20 2 )×14=18.22cm 3 . Take 1 / 3 of the lubricating oil, which is 6.07cm 3 .

[0060] Use a standard oiler with an oil filling port diameter of 6mm. The oil nozzle fits tightly against the bearing oil filling port without oil leakage.

[0061] The standing time is 5 minutes, during which the bearing is rotated several times to ensure that the oil film is evenly covered, wetting all contact surfaces and avoiding dry friction losses.

[0062] In this embodiment, step S2 specifically includes:

[0063] 1. Initial friction state measurement

[0064] 1.1 Experimental conditions setting:

[0065] Load F: Set the load on the bearing during normal operation of the equipment, for example 1000 Newtons. This value is based on the design specifications of the equipment and actual operating conditions.

[0066] Speed ​​v: Set the bearing speed to 1500 RPM (revolutions per minute). Determine according to the operating speed of the equipment and the manufacturer's recommended parameters.

[0067] 1.2. Initial current signal recording:

[0068] A high-precision electrometer was used to record the initial current signal I generated by TENG. initial The accuracy of the data is guaranteed according to the accuracy of the measuring equipment, for example 0.1 picoampere.

[0069] Reference current signal I initial =f static (F, v): Under the set load and speed, it reflects the friction current when the bearing is in a good lubrication state.

[0070] 2. Establish a feature signal library

[0071] 2.1. Simulation of different states:

[0072] Oil deficiency determination: Reduce the amount of lubricating oil to 50% of the normal level and accurately control the reduction amount to ensure the repeatability of the experiment.

[0073] Record the friction current I oil depleted , if it is 1.5 times I initial , then I oil depleted =1.5·I initial .

[0074] Calculate the current change ΔI oil =I oildepleted -I initial . If I initial =1 picoampere, then ΔI oil =0.5 picoampere.

[0075] Excessive friction condition determination: Increase the bearing load to 1500 Newtons or increase the speed to 2000 RPM to simulate extreme conditions.

[0076] Record the friction current I highfriction , if it is twice as large as I initial , that is I highfriction =2·I initial .

[0077] Calculate the current change ΔI friction =I highfriction -I initial .

[0078] 2.2. Construction of feature signal library:

[0079] Record the ΔI values ​​and their corresponding lubrication conditions under all different conditions and establish a detailed table or database for comparison in subsequent real-time monitoring.

[0080] 3. Judgment logic:

[0081] The current change ΔI_real measured in real time is compared with the ΔI in the characteristic signal library.

[0082] If ΔI_real=0: the lubrication condition is good.

[0083] If ΔI_real≥0.5 (corresponding to oil shortage): the lubricant may be insufficient and the lubrication needs to be checked.

[0084] If ΔI_real ≥ 1 (corresponding to excessive friction): the friction is too high and the load may need to be reduced or lubrication may need to be increased.

[0085] Alarm mechanism: The thresholds are set to 0.5 picoampere and 1 picoampere. When ΔI_real is detected to exceed these thresholds, the system immediately generates an alarm prompt.

[0086] Data storage and tracking: Continuously record all current signals and status information, and update the signal library to improve the accuracy and reliability of the system.

[0087] In this embodiment, step S3 specifically includes:

[0088] 1. Current signal acquisition

[0089] Sampling frequency: Set to 1000Hz, that is, collect 1000 current values ​​per second to ensure the capture of instantaneous changes, suitable for high-speed rotating mechanical systems.

[0090] Data format: stored in the format of (T, I) group, T is the timestamp (accurate to milliseconds), I is the current value (unit: picoampere).

[0091] 2. Signal processing and analysis

[0092] 2.1 Data preprocessing steps:

[0093] De-noising: Use FIR low-pass filter with the cut-off frequency set to 30 Hz to filter out high-frequency noise such as mechanical vibration and retain low-frequency signals to reflect changes in lubrication status.

[0094] Signal smoothing: Use the moving average method (the window size is set to 10 data points) to smooth the signal and reduce the impact of transient spikes on the average value.

[0095] 2.2 Feature extraction:

[0096] Average current I avg :The calculation formula is I avg =ΣI(t) / N, where N is the total number of samples. It is used to represent the overall friction characteristics.

[0097] Current variance σ 2 :The calculation formula is σ 2 =Σ(I(t)-I avg ) 2 / N, reflects the stability of current changes.

[0098] Current peak I peak : Record the maximum current value in the data set, and set the threshold to I initial +20%I initial , exceeding indicates a possible anomaly.

[0099] 2.3. Calculation of characteristic signal change rate:

[0100] Rate of change δI=|I(t)-I initial | / I initialIf δI>0.15 (i.e. more than 15%), further analysis is required.

[0101] 3. Fault warning and response

[0102] Continuous abnormal capture: Set three consecutive samplings (i.e. within 3 milliseconds) when δI exceeds 0.15 to trigger a system alarm.

[0103] Alarm output form: The computer interface displays "Insufficient lubrication" or "Increased friction" text alarms, and issues an 85dB sound reminder to ensure timely response by personnel.

[0104] Inspection measures: Prompt to check the lubricant level, with specific suggestions to "add 10mL of lubricant" or "check the integrity of the sealing ring for damage."

[0105] Recording and feedback: The system automatically generates logs to record time, exception type, and response measures for subsequent analysis and adjustment of maintenance strategies.

[0106] Example 2

[0107] A friction pair lubrication state monitoring device under fluid lubrication conditions based on TENG as described in this embodiment includes a bearing, an oil filling port, a wire, an electrometer, and a computer.

[0108] The bearing is provided with a base for support, and the bearing is accommodated in a central hole provided in the base. The base is rectangular and has mounting holes symmetrically provided on both sides. The base is fixed by bolts matching the mounting holes. The base is made of thickened cast iron, which makes the load-bearing capacity about 30% higher than that of an ordinary bearing seat.

[0109] The bearing includes an inner ring, an outer ring, rolling elements and a sealing ring. The outer ring is fixed to the center hole of the bearing base. The thickness of the inner ring is greater than that of the outer ring. One side of the inner ring is flush with the outer ring, and the other side protrudes from the outer ring. The inner ring is provided with a set screw hole to ensure that the bearing and the shaft are easier to lock. There are two sets of sealing rings located at the junction of the inner ring and the outer ring on both sides, which are used to block dust and debris from the outside, and also to ensure the stable flow of lubricating oil between the rolling element and the inner and outer rings.

[0110] The oil filling port is used to inject new lubricating oil.

[0111] One end of the wire is fixed to the inner ring of the bearing through the oil filling port. Because this embodiment uses a vertical bearing seat, the bearing is mainly subjected to radial force when connected to the shaft, and when the bearing rotates, it is mainly the inner ring that rotates. When the lubricating oil is consumed, the friction state will change. The friction between the rolling element and the inner and outer rings will intensify, and the friction of the inner ring is greater than that of the outer ring, so the wear of the inner ring is more serious, so the wire is fixed to the inner ring, so that the generated fixed signal is more obvious. The other end of the wire is connected to the electrometer, and the specific current changes can be displayed on the computer.

[0112] Example 3

[0113] Gearboxes are used as transmission devices in various mechanical equipment. Gearboxes are generally sealed. The lubrication status of the gearbox is judged by manually observing the change in oil level. Based on the detection method and device of Examples 1 and 2, a wire is led out from the gearbox body, connected to an electrometer, and then connected to a computer. The gearbox is judged by the different electrical signals generated by the gearbox under different friction conditions, and the lubrication status inspection is completed without stopping or disassembling the equipment.

[0114] Example 4

[0115] Industrial robot arms are widely used in automobile manufacturing, metal processing, etc. Because the environment is full of dust, the joints of the robot arms are generally sealed. For the lubrication status of the joints, people check whether the lubricating oil is deteriorated. According to the contents of Examples 1 and 2, this embodiment connects an external wire to the joint and connects it to an electrometer, and then connects it to a computer. The joints of the industrial robot arm generate different electrical signals under different lubrication conditions, thereby judging the lubrication status.

[0116] In summary, the present invention will monitor the lubrication state of the sealing device based on TENG technology. Compared with other detection technologies, sensor monitoring can only monitor a single characteristic (pressure, temperature, flow, etc.), and cannot fully and accurately reflect the lubrication state. Vibration monitoring is easily affected by external factors. However, TENG detection technology can reflect the lubrication state of the sealing device in real time, comprehensively and unaffectedly. For different sealing devices, the TENG structure is reasonably designed and integrated into the friction part of the sealing device. The change of the friction state generates a change in the electrical signal to monitor the lubrication state.

[0117] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A friction pair lubrication state monitoring device under fluid lubrication conditions based on TENG, characterized in that: include: The bearing comprises an inner ring, an outer ring, a rolling element and a sealing ring, wherein the outer ring is fixed in the center hole of the base, and the inner ring is provided with a stop screw hole for locking; An oil filling port, used for injecting lubricating oil into the bearing; A wire, one end of which is fixed to the inner ring and the other end is connected to an electrometer to form a triboelectric nanogenerator TENG; An electrometer, used to detect and output a current signal caused by a change in the friction state; a computer, connected to the electrometer, for receiving and analyzing the current signal; The base is used to carry and fix the bearing, and is provided with mounting holes for installation. The mounting holes are symmetrically arranged on both sides, and the base is fixed by bolts.

2. The lubrication state monitoring device for friction pairs under fluid lubrication conditions based on TENG as claimed in claim 1, characterized in that: The bearing includes an inner ring, an outer ring, rolling elements and a sealing ring. The outer ring is fixed in the center hole of the base, and the inner ring is thicker than the outer ring. One side of the inner ring is flush with the outer ring, and the other side protrudes from the outer ring. The inner ring is provided with a set screw hole to ensure the effective locking of the bearing and the shaft to provide stable support when the equipment is running.

3. The lubrication state monitoring device for friction pairs under fluid lubrication conditions based on TENG as claimed in claim 1, characterized in that: The sealing ring is installed between the inner ring and the outer ring of the bearing to prevent external dust and debris from entering the interior of the bearing.

4. The device for monitoring the lubrication state of a friction pair under fluid lubrication conditions based on TENG as claimed in claim 1, characterized in that: The oil filling port is arranged on the outer ring of the bearing and is used to inject lubricating oil into the bearing to ensure that the rolling elements are well lubricated between the inner and outer rings.

5. The lubrication state monitoring device for friction pairs under fluid lubrication conditions based on TENG as claimed in claim 1, characterized in that: One end of the wire is fixed to the inner ring through the oil filling port, and the other end is connected to the electrometer, ensuring that when the lubricating oil is consumed and the friction state changes, the wire can effectively transmit the electrical signal generated by TENG.

6. A method for monitoring the lubrication state of a surface-to-surface friction pair under fluid lubrication conditions based on TENG, characterized in that: The following steps are involved: S1: Select TENG components suitable for the bearing to be monitored, including bearings, wires, electrometers, etc.; fix one end of the wire to the inner ring of the bearing and connect the other end to the electrometer to detect the electrical signal caused by friction changes; inject appropriate lubricating oil through the oil filling port of the bearing to ensure good initial lubrication state; S2: Under static or normal working conditions, record the initial current signal generated by TENG to establish the baseline electrical signal of the bearing in a good lubrication state; compare the good lubrication state with different degradation or fault states, and establish the corresponding electrical signal feature library as a reference for subsequent monitoring; S3: During the operation of the device, the electrometer continuously collects the current signal transmitted by the wire; since the change of friction state will cause the change of the output current characteristics of TENG, an electrometer is needed to capture these subtle changes; The collected current signal is transmitted to the computer, and the signal is processed and analyzed using special software; the current lubrication status is determined by comparing it with the characteristic signal library; S4: When the current signal deviates from the initial state or the normal range in the characteristic signal library, the system automatically determines that the bearing lubrication state is poor, and problems such as increased friction and wear or insufficient lubricant may occur; once an abnormal signal is detected, the system will generate an early warning prompt and notify the maintenance personnel through a computer display or other alarm system; according to the type of problem detected, specific maintenance suggestions are given, such as adding lubricant, checking the integrity of the seal ring, or replacing bearing components; S5: Record all monitoring data and maintenance operations, and conduct trend analysis to optimize equipment operation and maintenance strategies; The feature signal library and monitoring algorithm are continuously updated based on actual operating conditions to improve signal recognition accuracy and false alarm rate.

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