Friction plate detection system
By using bend detection wires and shape memory alloy microwires to monitor friction pad wear in real time, combined with sensors and control modules, the problem of low detection accuracy of traditional friction pads is solved, enabling precise utilization of friction pads and improved driving safety.
Patent Information
- Application Number
- CN202511767591.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-28
- Publication Date
- 2026-01-20
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Traditional friction pad wear detection has low accuracy and cannot identify micro-cracks and warping, resulting in a linear decline in the performance of the friction pads and failing to maximize their utilization. Furthermore, it cannot accurately determine the braking time when wear is severe, posing a traffic safety hazard.
The device uses a bending detection wire and a shape memory alloy microwire to detect the bending deformation of the friction plate. Combined with a speed sensor and a driver, it monitors the wear of the friction plate in real time. The control module judges the degree of wear and dynamically adjusts the braking torque. It is equipped with a heating module to restore the shape of the friction plate and provides safety threshold values and braking time calculations.
It enables precise detection of friction pad wear, maximizes utilization, reduces vehicle operating costs, ensures driving safety, dynamically adjusts vehicle speed and braking torque, and extends the service life of friction pads.
Smart Images
Figure CN121363598A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of automobile braking, including electric vehicles, and specifically relates to a friction plate detection system. BACKGROUND
[0002] The traditional wear detection of the friction plate of an automobile (including an electric vehicle and a hybrid vehicle). A thickness sensor or a mechanical alarm is usually used, which has a simple structure and low detection accuracy, can only reflect the final remaining thickness, cannot identify the early effect decline such as micro-cracks and warping, and whether replacement is needed still depends on manual judgment, has large errors, cannot maximize the utilization rate of the friction plate under the premise of safe use, and causes high user vehicle cost. In addition, such a structure usually reaches the use limit of the friction plate when detecting that the friction plate is seriously worn, so before that, the use effect of the friction plate has been linearly decreased, and then in this process, the user does not know the specific wear condition of the friction plate, so the control of the driving speed of the automobile cannot be accurate, and in this case, the actual stopping time cannot be accurately judged during sudden braking in the process of rapid driving, which may cause traffic accidents and endanger life safety. SUMMARY
[0003] The present application provides a friction plate detection system to solve the above-mentioned technical problems, specifically using the following technical scheme: A friction plate detection system, comprising: a friction plate configured to be pressed against a hub side to achieve braking; a bending detection wire is embedded on the side of the friction plate away from the hub side, and is configured to detect the bending deformation of the friction plate body; the bending detection wire is provided with a maximum deformation detection value, which corresponds to the maximum deformation degree of the friction plate, i.e., the maximum wear degree of the friction plate; the friction plate detection system further comprises: a control module configured to determine whether there is a micro-crack or abnormal deformation according to the bending detection value of the bending detection wire, and to determine whether to replace the friction plate when the difference between the bending detection value of the bending detection wire and the maximum deformation detection value is less than a preset value.
[0004] Further, the friction plate detection system further comprises: an iron shoe for mounting the friction plate through the back plate, a driver for driving the iron shoe to press the friction plate to the hub side, a driving device for driving the hub, and a rotating speed sensor for detecting the rotating speed of the hub; the driving pressure of the driver for braking and the detected rotating speed value of the rotating speed sensor constitute a corresponding value; when the corresponding value changes by a first threshold value, it is judged that the friction plate has a first degree of wear; when the corresponding value changes by a second threshold value, it is judged that the friction plate has a second degree of wear; when the friction plate has the first degree of wear, the first braking boundary point of the friction plate is determined according to the detected value of the rotating speed sensor, the driving pressure value of the driver, the braking stroke of the driver, and the detected value of the bending detection wire; when the friction plate has the second degree of wear, the second braking boundary point of the friction plate is determined according to the detected value of the rotating speed sensor, the driving pressure value of the driver, the braking stroke of the driver, and the detected value of the bending detection wire; when the second braking boundary point is reached, it is judged that the friction plate is replaced.
[0005] Further, when the second braking boundary point is reached, the driving device drives the hub to continuously rotate, and the driver drives the friction plate to always maintain a braking state until the rotating speed value in the corresponding value is greater than zero within a preset driving distance threshold after driving braking at a preset driving pressure, and at this time, the corresponding detected value of the bending detection wire is defined as a dangerous value.
[0006] Further, the friction plate is further provided with a shape memory alloy micro-wire for restoring the bending of the friction plate; the friction plate detection system is further provided with a heating module for driving the shape memory alloy micro-wire to shrink to restore the bending of the friction plate; the shape memory alloy micro-wire is arranged in a grid shape in the interior of the friction plate; when the detected value of the bending detection wire is the dangerous value, the control module controls the heating module to heat.
[0007] Further, when the second braking boundary point is reached, the difference between the detected value of the bending detection wire and the dangerous value is less than a preset threshold value, and the detected value of the bending detection wire is defined as a safe critical value.
[0008] Further, the friction plate detection system is communicatively connected to the driving device; the driving device obtains the detection information of the friction plate detection system, and calculates the current safe speed limit according to the change of the detection information.
[0009] Further, when the first braking boundary point is reached, the control module calculates the required braking time corresponding to different speeds according to the rotating speed detection value of the rotating speed sensor and the driving pressure value of the driver, and calculates a safe first speed limit region according to a safe braking time region; when the second braking boundary point is reached, the control module calculates the required braking time corresponding to different speeds according to the rotating speed detection value of the rotating speed sensor and the driving pressure value of the driver, and calculates a safe second speed limit region according to a safe braking time region; the maximum speed limit of the second speed limit region is less than the minimum speed limit of the first speed limit region.
[0010] Further, the control module dynamically allocates the motor braking torque and the friction braking torque according to the wear level of the friction plate; when the wear level of the friction plate exceeds a set threshold, the motor feedback braking is preferentially enabled; the wear level is divided into three levels of normal, mild and severe; and the energy recovery control module dynamically optimizes the torque allocation by using a reinforcement learning algorithm.
[0011] Further, the bending detection wire comprises a Ni-Cu alloy micro metal wire and a polyimide insulating layer wrapped around the metal wire; the two ends of the metal wire are crimped with metal terminals and led out to the back surface of the back plate to form a weldable electrical interface; the metal wire is arranged in a sinusoidal wave along the width direction of the friction plate at the connection between the back plate and the friction plate; the resistance value of the metal wire linearly changes with the bending of the friction plate, and is used for real-time output of a bending deformation signal.
[0012] Further, the friction plate is also provided with a temperature wire for detecting the temperature of the friction plate; the bending detection wire and the temperature wire constitute a Wheatstone full-bridge four-arm inside the friction plate body, and are led out to the back surface of the steel back through four tinned copper foils on the same side, so that temperature-bending decoupling is realized without an external temperature compensation resistor.
[0013] The friction plate detection system has the advantages that the wear degree of the friction plate can be accurately detected and known, the replacement of the friction plate is more accurate through detection, the utilization rate of the friction plate can be maximized under the premise of safe use, and the vehicle use cost of a user is reduced. BRIEF DESCRIPTION OF DRAWINGS
[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.
[0015] Figure 1 is a schematic diagram of a friction plate detection system of the present application; Figure 2 is a schematic diagram of a friction plate of a friction plate detection system of the present application; The friction plate detection system 10, the friction plate 11, the bending detection wire 12, the temperature wire 13, the shape memory alloy micro wire 14, the heating module 15, the control module 16, the driver 17, the driving device 18, the speed sensor 19, and the iron shoe 20. DETAILED DESCRIPTION
[0016] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.
[0017] like Figure 1 and Figure 2 As shown, a friction pad detection system 10 includes a friction pad 11, which is used to press against the wheel hub side to achieve braking. During use, due to the pressing operation of the brake shoe 20, the friction pad 11 generates a large frictional force with the braking side of the wheel hub, forcing the wheel hub to stop rotating. During this braking process, the friction pad 11 will wear. After wearing, the friction pad 11 will deform due to wear deformation during the further pressing operation of the brake shoe 20. As the degree of deformation gradually increases, the friction pad 11 is prone to microcracks and warping.
[0018] To address the above situation, a bending detection wire 12 is embedded on the side of the friction plate 11 away from the wheel hub. The bending deformation of the friction plate 11 can be detected by the bending detection wire 12. In other words, the bending detection wire 12 has a maximum deformation detection value. During research, development, production, and testing, the maximum deformation detection value of the bending detection wire 12 for different models of friction plates 11 is determined based on experimental data. This maximum deformation detection value can be a range of values. This maximum deformation detection value corresponds to the maximum deformation that the friction plate 11 can withstand, i.e., the maximum wear degree of the friction plate 11. Changes in the detection data of the bending detection wire 12 correspond to the wear condition of the friction plate 11. Users can monitor the usage status of the vehicle's friction plate 11 in real time based on the detection data of the bending detection wire 12 and make adaptive replacements as needed. For example, when driving under different road conditions, users can refer to the specific condition of the friction plate 11 to choose whether replacement is necessary.
[0019] The aforementioned friction pad detection system 10 also includes a control module 16. The control module 16 determines the presence of microcracks or abnormal deformation based on the bending detection value of the bending detection wire 12. When the difference between the bending detection value of the bending detection wire 12 and the maximum deformation detection value is less than a preset value, it determines that the friction pad 11 needs to be replaced. At this point, the wear of the friction pad 11 is close to the replacement requirement. Before this, it can still be used relatively safely for braking; after this, there is a risk of friction pad 11 breakage, necessitating replacement. The preset value for the difference between the bending detection value of the bending detection wire 12 and the maximum deformation detection value can be determined based on research and development experimental data.
[0020] Specifically, the bending detection wire 12 includes a Ni-Cu alloy micro metal wire and a polyimide insulating layer wrapped around the outer periphery of the metal wire. The two ends of the metal wire are crimped with metal terminals and led out to the back of the back plate to form a solderable electrical interface. The metal wire is sinusoidal along the width direction of the friction plate 11 at the connection between the back plate and the friction plate 11. The resistance value of the metal wire changes linearly with the bending of the friction plate 11, which is used to output the bending deformation signal in real time. In this scheme, the Ni-Cu alloy wire (Ø0.12 mm) is pre-buried at the interface between the back plate and the friction plate 11. The sinusoidal wave has 3 periods, a wavelength of 10 mm, a peak-to-valley height of 3 mm, and a total length of about 60 mm. The nominal resistance is 12 Ω. With a 2 mm deflection, ΔR=42 mΩ is taken as the "maximum deformation detection value". When the measured ΔR≥42 mΩ-3 mΩ (preset hysteresis), the control module 16 outputs the "replace the friction plate 11" signal. In this way, pure resistance measurement is used, the response is fast (<1 ms), it is not affected by electromagnetic interference, the terminal is pre-buried in a fine way, the strength of the friction plate 11 is not weakened, and the signal is stable.
[0021] In the early stage of the development of this scheme, 10 front brake pads (steel back + resin-based friction material, thickness 10 mm) of the same batch of passenger cars were selected. The bending detection wire 12 used is a Ni-Cu Ø0.12 mm, with a sinusoidal wave of 3 periods, R0=12.00 Ω, and a full-bridge power supply of 2.5V. The experimental machine was used to obtain the following table of data: Center deflection δ (mm) Micro-strain ε (µε) Resistance change ΔR (mΩ) Bridge output Vout (mV) Wear amount* (mm) Visual / CT result 0.00 0 0.0 0.0 0.0 Intact 0.20 210 2.5 1.04 0.15 Intact 0.40 420 5.0 2.08 0.30 Intact 0.60 630 7.6 3.17 0.45 Intact 0.80 840 10.1 4.20 0.60 Microcracks < 0.1 mm 1.00 1050 12.6 5.25 0.75 Micro-crack 0.2 mm 1.20 1260 15.1 6.30 0.90 Crack 0.4 mm 1.40 1470 17.7 7.38 1.05 Crack 0.6 mm 1.60 1680 20.2 8.42 1.20 Crack >0.8 mm 1.80 1890 22.8 9.50 1.35 Soon to break 2.00 2100 25.3 10.54 1.50 Broken The upper limit of the safety threshold can continue to be used, for example, δ=1.20 mm, ΔR=15.1 mΩ, corresponding to a crack of 0.4 mm, and the maximum deformation detection value is 15.1 mΩ. Experiments show that when δ≥1.60 mm, the crack is >0.8 mm, and the probability of rupture increases sharply. Therefore, when the measured ΔR>15.1 mΩ-5.1 mΩ=10.0 mΩ, the system prompts "replace". ΔR=15.1 mΩ is set as the maximum deformation detection value, and the preset difference is 5.1 mΩ. When the bending detection wire 12 outputs ΔR≥10.0 mΩ, the control module 16 determines that the friction plate 11 has entered the "replacement interval", at which time the crack length is about 0.6 mm, and emergency braking can still be performed, but it needs to be replaced within the recommended mileage range, such as within 500 km, to avoid the risk of rupture.
[0022] Further, the friction plate 11 is also provided with a temperature wire 13 which can detect the temperature of the friction plate 11. The curvature detection wire 12 and the temperature wire 13 constitute a Wheatstone full-bridge four-arm inside the body of the friction plate 11, and are led out to the back surface of the steel back through four tinned copper foils on the same side, realizing temperature-bend decoupling without external temperature compensation resistance. That is, one "temperature-sensitive" wire and one "temperature + bend-sensitive" wire are arranged according to the four arms of the Wheatstone bridge, and the temperature component can be removed by algebraic method through one voltage sampling, leaving a pure bend signal, that is, "temperature-bend decoupling". The curvature detection wire 12 goes "sine wave" → T+B affected, the temperature wire 13 goes "straight line" → only T affected, the temperature history of the two wires is completely consistent. Four-arm full-bridge, the structure of the same type of arms makes the temperature drift automatically offset without additional temperature compensation resistance. MCU samples Vout, and directly obtains micro-strain ε using Vout = K·ε, with a temperature error of < ±0.2% FS. "Temperature-bend decoupling" is to "cut off" the temperature error using the symmetry of the bridge, so that the curvature detection wire 12 only outputs a "pure bend" signal and is no longer affected by environmental temperature or friction heat.
[0023] The friction plate detection system 10 described above can accurately detect and know the wear degree of the friction plate 11, more accurately judge whether to replace the friction plate 11 through detection, maximize the utilization rate of the friction plate 11 under the premise of safe use, and reduce the user's vehicle cost. At the same time, such a structure can roughly judge the stopping time according to the wear degree during the detection of the wear process of the friction plate 11, so that the user can consciously control and adjust the vehicle speed according to the road conditions to ensure driving safety.
[0024] Further, the friction plate detection system 10 further comprises an iron shoe 20, a driver 17, a driving device 18 and a rotation speed detector. The driving device 18 drives the hub to rotate and travel, the iron shoe 20 is installed and fixed to the friction plate 11 through the back plate, and then the driver 17 is connected to the iron shoe 20 to drive the iron shoe 20, so as to press the friction plate 11 to the hub side and realize braking of the hub. The rotation speed sensor 19 is used to detect the rotation speed of the hub. The iron shoe 20, the driver 17, the driving device 18 and the rotation speed detector are conventional devices provided on the existing automobile, and the difference in the present scheme is that the driving pressure of the driver 17 for braking and the detected rotation speed value of the rotation speed sensor 19 constitute a corresponding value. The corresponding value implies the braking stroke and braking time, that is, after the friction plate 11 is worn, it needs a longer braking stroke and braking time to reach the required braking pressure.
[0025] When the corresponding value changes by a first threshold value, it is determined that the friction plate 11 has a first degree of wear. When the friction plate 11 has a first degree of wear, the first brake boundary point of the friction plate 11 is determined according to the detection value of the rotation speed sensor 19, the driving pressure value of the driver 17, the brake stroke of the driver 17, and the detection value of the bending detection wire 12.
[0026] When the corresponding value changes by a second threshold value, it is determined that the friction plate 11 has a second degree of wear. When the friction plate 11 has a second degree of wear, the second brake boundary point of the friction plate 11 is determined according to the detection value of the rotation speed sensor 19, the driving pressure value of the driver 17, the brake stroke of the driver 17, and the detection value of the bending detection wire 12.
[0027] When the second brake boundary point is reached, it is determined that the friction plate 11 needs to be replaced. That is, the friction plate 11 at this time has a large degree of wear and requires a long brake stroke, brake pressure, and brake time to complete the braking of the predetermined distance.
[0028] In the present scheme, the first threshold value change is that the average value of the corresponding value deviates by 8% or less, and the second threshold value change is that the average value of the corresponding value deviates by 8% to 15%.
[0029] The driver 17 described above is a pressure sensor mounted on the cylinder wall of the automobile brake caliper, and the rotation speed sensor 19 is a magneto-rotational speed sensor 19 mounted on the hub bearing side. Under the same brake pedal stroke, the steady-state pressure P and the wheel rotation speed V are recorded. In the development process of the present scheme, experiments were conducted on the same friction plate 11, the pedal stroke was fixed (5 mm step), the pressure was gradually increased from 0→100%, the driven wheel was kept at a constant speed (500 / 1000 / 1500 / 2000 rpm), the steady-state pressure was recorded for each speed, repeated 3 times, and the average value was taken, and the abnormal value was eliminated (3σ principle). The experimental data table is as follows: Table 1: List of equipment Sensor Model Accuracy Interface Brake pressure MEMS 0-20 MPa ±0.5 %FS 4-20 mA Hub speed Magnetoelectric 0-3000 rpm ±1 rpm TTL Pedal travel Resistive 0-50 mm ±0.1 mm 0-5 V Table 2: Example of partial data Pedal travel % Pressure P (MPa) Speed V (rpm) Note 0 0.0 2000 Zero position 20 2.1 1980 Steady state 40 4.3 1940 Steady state 60 6.5 1860 Steady state 80 8.7 1720 Steady state 100 10.8 1520 Steady state As a specific embodiment, when the second braking boundary point is reached, the driving device 18 drives the wheel hub to rotate at a preset speed, the driver 17 drives the friction plate 11 to brake, and the speed is greater than zero after braking for a preset time at a preset driving pressure when the speed value in the corresponding value is within a preset driving distance threshold. At this time, the corresponding detection value of the bending detection wire 12 is defined as a dangerous value. That is, when the second braking boundary point is reached, the user or the factory detection merchant can drive the vehicle to travel at a preset speed, and the speed is greater than zero after braking for a preset time at a preset driving pressure. At this time, the braking effect of the friction plate 11 has affected the normal braking, reaching a relatively dangerous state. In this case, the user needs to replace the friction plate 11 in time. The preset driving pressure usually adopts a larger braking stroke. The preset parameters in the experiment can be set as standard parameters on the corresponding applied vehicle, and the friction plate 11 matched with different vehicles has its system of standard parameters tested by experiments.
[0030] As a specific embodiment, the friction plate 11 is further provided with a shape memory alloy micro-wire 14 for restoring the bending of the friction plate 11. The friction plate detection system 10 is further provided with a heating module 15 for driving the shape memory alloy micro-wire 14 to contract and restore the bending of the friction plate 11. The shape memory alloy micro-wire 14 is arranged in a grid shape in the interior of the friction plate 11. When the detection value of the bending detection wire 12 is a dangerous value, the control module 16 controls the heating module 15 to heat, so as to restore the bending of the shape of the friction plate 11 to a certain extent and improve the friction performance, thereby ensuring that the vehicle can normally travel for a period of time when the detection value of the bending detection wire 12 is in a dangerous state, giving the user time to replace the friction plate 11, and thereby improving the vehicle travel safety as much as possible in a relatively dangerous driving state. The heating module is a power supply circuit for providing current to the shape memory alloy micro-wire 14.
[0031] As a specific embodiment, when the second braking boundary point is reached, the difference between the detection value of the bending detection wire 12 and the dangerous value is less than a preset threshold, and the detection value of the bending detection wire 12 is defined as a safe critical value. In this state, the user's brake pad can still be used to a certain extent, and the user needs to replace the friction plate 11 according to the vehicle condition. That is, after reaching the second braking boundary point, the n times of braking can be selected first, and the interval time and the braking times can be set according to the actual situation. For example, 20 braking data are recorded, and when the difference between the 20th bending detection wire 12 output data and the dangerous value is less than 2 mΩ, the point is set as the "safe critical value", which eliminates the accidental error of single measurement and gives the safe upper limit for long-term operation. In the initial experiment, 10 friction plate 11 samples with a critical value of 38.2±1.1 mΩ were taken, the corresponding actual deflection of the bending detection wire 12 was 1.6 mm, and a 10% safety threshold was left.
[0032] As a preferred mode, the friction plate detection system 10 is communicatively connected to the driving device 18, the driving device 18 obtains the detection information of the friction plate detection system 10, and calculates the current safe speed limit according to the change of the detection information. Specifically, when the first braking boundary point is reached, the control module 16 calculates the required stopping time corresponding to different speeds according to the rotation speed detection value of the rotation speed sensor 19 and the driving pressure value of the driver 17, and the stopping time corresponds to a braking distance, and then calculates the safe first speed limit area according to the safe stopping time area. When the second braking boundary point is reached, the control module 16 calculates the required stopping time corresponding to different speeds according to the rotation speed detection value of the rotation speed sensor 19 and the driving pressure value of the driver 17, and the stopping time corresponds to a braking distance, and then calculates the safe second speed limit area according to the safe stopping time area. The maximum speed of the second speed limit area is less than the minimum speed of the first speed limit area.
[0033] For example, according to the experimental measurement of the same friction plate 11 at the first braking boundary point (light wear), the required braking distance at different initial speeds (120→0 km / h) is calculated, and the required braking distance is <55 m in the first speed limit area: 80-120 km / h, and the required braking distance is <40 m in the second speed limit area: ≤80 km / h, and the distance prediction error in the test is <±2m. The experiment is based on a unified braking stroke, that is, the opening and closing distance of the pedal is uniform. During the experiment, the pedal is quantitatively stepped by the pedal device, and the program is quantitatively controlled, which is more accurate. The detection data of different types of friction plates 11 is different, and the corresponding system parameters can be set according to the detection data of different types of friction plates 11. In this way, the safety boundary is quantified, and the driver does not need to learn extra, and can perform real-time feedback of the safe speed limit through the detection data of the detection system.
[0034] As a specific embodiment, in a hybrid vehicle, the driving device 18 includes two sets of driving mechanisms of motor driving and engine driving, and in an electric vehicle, the driving device 18 includes motor driving. In these two cases, the driving device 18 can dynamically allocate motor braking torque and friction braking torque according to the wear level of the friction plate 11. That is, when the wear level of the friction plate 11 exceeds the set threshold, the motor feedback braking is preferentially enabled. Specifically, the wear level is divided into three levels of normal, light and heavy, and the control module 16 uses a reinforcement learning algorithm to dynamically optimize torque distribution.
[0035] In the scheme, the control module 16 adopts the DDPG reinforcement learning algorithm, taking the wear grade, temperature, SOC, vehicle speed, pedal opening, motor speed, deceleration request as the 7-dimensional state, and outputting the motor braking ratio alpha belongs to [0, 1]. In addition, based on the above scheme, the energy recovery module in the motor drive system can recover energy according to the brake drive of the motor. In a braking cycle, the recovered energy ΔE_rec is normalized, and its weight is 0.7. The wear volume Δwea (mm³) converted by the increment of the bending detection wire 12 is normalized, and its weight is 0.3. The weight of the action change penalty (to suppress jitter and smooth the braking feeling) is 0.05. Then: The reward function r = 0.7 ΔE_rec - 0.3 Δwear - 0.05 | Δa | 2; After offline training for 200k steps, the average reward is 195, the online 100 ms cycle reasoning is carried out, the OTA incremental update is carried out, and the energy recovery rate is improved by 12% and the wear is reduced by 15% in the heavy wear detection and verification of the real vehicle.
[0036] In summary, the friction plate detection system of the scheme can realize real-time sensing of the deformation bending, temperature and wear grade of the friction plate, recognize micro cracks, and start the self-repair function after heavy wear, which can ensure the driving safety to a certain extent. According to the wear degree, the safety speed is dynamically limited to ensure the driving safety, and during the wear process, the model output can also be used to preferentially use the motor feedback braking to prolong the service life of the friction plate.
[0037] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the above examples do not limit the present application in any form, and any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present application.
Claims
1. A friction plate inspection system, comprising: The friction plate is used to be pressed against the hub side to realize braking, characterized in that, The side of the friction plate away from the hub side is embedded with a bending detection wire for detecting the bending deformation of the friction plate body; The bending detection wire is provided with a maximum deformation detection value corresponding to the maximum deformation degree of the friction plate, i.e. the maximum wear degree of the friction plate; The friction plate detection system further comprises a control module for judging whether there is micro-crack or abnormal deformation according to the bending detection value of the bending detection wire, and judging to replace the friction plate when the difference between the bending detection value of the bending detection wire and the maximum deformation detection value is less than a preset value.
2. The friction plate detection system according to claim 1, characterized in that, The friction plate detection system further comprises an iron shoe for mounting the friction plate through a back plate, a driver for driving the iron shoe to press the friction plate against the hub side, a driving device for driving the hub, and a rotating speed sensor for detecting the rotating speed of the hub; The driving pressure of the driver for braking and the detected rotating speed value of the rotating speed sensor constitute a corresponding value; When the corresponding value changes by a first threshold value, it is judged that the friction plate has a first degree of wear; When the corresponding value changes by a second threshold value, it is judged that the friction plate has a second degree of wear; When the friction plate has a first degree of wear, the first braking boundary point of the friction plate is determined according to the detection value of the rotating speed sensor, the driving pressure value of the driver, the braking stroke of the driver, and the detection value of the bending detection wire; When the friction plate has a second degree of wear, the second braking boundary point of the friction plate is determined according to the detection value of the rotating speed sensor, the driving pressure value of the driver, the braking stroke of the driver, and the detection value of the bending detection wire; When the second braking boundary point is reached, it is judged to replace the friction plate.
3. The friction plate detection system according to claim 2, characterized in that, When the second braking boundary point is reached, the driving device drives the hub to continue rotating, and the driver drives the friction plate to always remain in a braking state until the rotating speed value in the corresponding value is greater than zero after driving braking at a preset driving pressure within a preset driving distance threshold, at which time the corresponding detection value of the bending detection wire is defined as a dangerous value.
4. The friction plate detection system according to claim 3, characterized in that, The friction plate further comprises a shape memory alloy micro-wire for restoring the bending of the friction plate; The friction plate detection system further comprises a heating module for driving the shape memory alloy micro-wire to contract to restore the bending of the friction plate; The shape memory alloy micro-wire is arranged in a grid shape inside the friction plate; When the detection value of the bending detection wire is the dangerous value, the control module controls the heating module to heat.
5. The friction plate detection system according to claim 3, characterized in that, When the detection value of the bending detection wire is less than a preset threshold value after the second braking boundary point is reached, the detection value of the bending detection wire is defined as a safe critical value.
6. The friction plate detection system according to claim 5, wherein the friction plate detection system is communicatively connected to the driving device. The driving device acquires detection information of the friction plate detection system, and calculates the current safe speed limit according to the change of the detection information.
7. The friction plate detection system according to claim 6, wherein when the first braking boundary point is reached, the control module calculates the required braking time corresponding to different speeds according to the rotation speed detection value of the rotation speed sensor and the driving pressure value of the driver, and calculates the safe first speed limit region according to the safe braking time region; when the second braking boundary point is reached, the control module calculates the required braking time corresponding to different speeds according to the rotation speed detection value of the rotation speed sensor and the driving pressure value of the driver, and calculates the safe second speed limit region according to the safe braking time region; The maximum speed limit of the second speed limit region is less than the minimum speed limit of the first speed limit region.
8. The friction plate detection system according to claim 7, wherein the control module dynamically allocates the motor braking torque and the friction braking torque according to the wear level of the friction plate; When the wear level of the friction plate exceeds the set threshold, the motor regenerative braking is preferentially enabled; The wear level is divided into three levels: normal, mild and severe; and the energy recovery control module uses a reinforcement learning algorithm to dynamically optimize the torque allocation.
9. The friction plate detection system according to claim 1, wherein the bending detection wire comprises a Ni-Cu alloy micro metal wire and a polyimide insulating layer wrapped around the outer periphery of the metal wire; The diameter of the metal wire is 0.08-0.15 mm; The metal wire is crimped at both ends with metal terminals and led out to the back of the back plate to form a weldable electrical interface; The metal wire is arranged in a sinusoidal wave along the width direction of the friction plate at the connection between the back plate and the friction plate; The resistance value of the metal wire changes linearly with the bending of the friction plate, which is used to output the bending deformation signal in real time.
10. The friction plate detection system according to claim 1, wherein the friction plate is further provided with a temperature wire for detecting the temperature of the friction plate; The bending detection wire and the temperature wire constitute a Wheatstone full-bridge four-arm inside the friction plate body, and are led out to the back of the steel back through four tinned copper foils on the same side, realizing temperature-bending decoupling without external temperature compensation resistor.