A method for measuring the abrasion amount of a brake pad of a high-speed train and a monitoring device

Abstract

The application discloses a kind of high-speed train brake shoe abrasion amount measurement method and monitoring device, the method includes the following steps: S1: a plurality of non-contact abrasion amount monitoring devices are arranged on high-speed train brake shoe;S2: distance data is preprocessed;S3: the cutting-in cutting-out end distance weight, brake frequency weight and temperature weight of the non-contact abrasion amount monitoring device are calculated;S4: establish abrasion thickness calculation model, and the abrasion thickness of each friction block is calculated;S5: the partial wear angle of the friction block of the area covered by non-contact abrasion amount monitoring device is calculated;S6: the actual contact area of friction block is calculated;S7: the abrasion amount of each friction block is calculated.The monitoring device measures the distance between brake shoe and brake disc based on TOF (Time of Flight) ranging technology, and the device integrates flexible installation module, angle adjusting module, temperature sensor and high-temperature resistant protection component.The application can more accurately measure and monitor the abrasion amount of high-speed train brake shoe.

Description

Technical Field

[0001] This invention relates to the field of rail vehicle braking technology, and in particular to a method and monitoring device for measuring the wear of brake pads on high-speed trains. Background Technology

[0002] As a core component of the train braking system, the wear condition of high-speed train brake pads directly affects braking performance and train safety. With the increase in high-speed rail operating speed and frequency, brake pads will experience significant wear during high-frequency, high-load braking processes. When the wear exceeds a critical value, it may lead to brake failure. Therefore, accurate and real-time monitoring of brake pad wear is of great engineering significance.

[0003] Currently, the railway industry mainly relies on manual visual inspection or contact sensor measurement to monitor brake pad wear. Manual inspection requires measuring each brake pad individually with tools such as calipers after the train has stopped, which is inefficient, subjective, and unable to capture the dynamic wear process. Contact measurement obtains displacement data by contacting the brake pad surface with mechanical probes, but it cannot solve the problem of real-time monitoring and is prone to amplified measurement errors and shortened sensor lifespan due to vibrations and high temperatures during high-speed train operation.

[0004] In addition, there are non-contact detection schemes based on visual image recognition for wear detection. However, this method is limited by complex lighting conditions and brake dust interference, making it difficult to work stably in actual working conditions. Furthermore, for brake pad monitoring under high-speed operation, a high-resolution image recognition device is required. In addition, recognition can only be performed after the brake pad and brake disc have stopped contacting each other, and it can only see the surface, which cannot accurately reflect the wear changes during the friction process.

[0005] During high-speed train braking, the surface temperature of the brake pads rises sharply, accompanied by high-frequency periodic vibrations. Optical measurement devices face two major technical bottlenecks: first, high temperatures cause performance drift in sensor components; second, vibrations induce optical path deviations or increase signal noise. Meanwhile, variations in the installation gap of the brake calipers and irregular surface morphology after brake pad wear also affect the accuracy of wear thickness measurements.

[0006] In addition, existing calculation methods for measuring brake pad wear in high-speed trains also have significant shortcomings: weak adaptability to operating conditions, with weight allocation often limited to the single dimension of physical distance, failing to fully integrate dynamic operating parameters such as braking frequency and temperature—the acceleration or inhibition effects of braking frequency differences and temperature fluctuations on wear are not quantified and incorporated, making it impossible to adapt to the complex and ever-changing actual operating environment; lack of compensation for uneven wear error, traditional methods do not construct an uneven wear-measurement correction closed loop, and the deviation of laser incident angle and contact area distortion caused by uneven wear are not dynamically compensated, causing the wear calculation to be affected by the long-term cumulative influence of geometric deviations; insufficient physical correlation of the model, with wear calculations often relying on the static assumption of nominal cross-sectional area, failing to integrate multiple physical field parameters such as uneven wear influence coefficient, load sensitivity coefficient, and speed conditions, ignoring the coupling effect of uneven wear, braking load, and running speed on contact area and wear rate, making it difficult to accurately reflect the real wear law under complex braking conditions of high-speed trains.

[0007] In summary, existing technologies lack systematic solutions for the aforementioned complex operating conditions, making it difficult to achieve dynamic and accurate measurement and trend prediction of wear. This leads to "excessive maintenance" of train maintenance relying on periodic replacement of brake pads or "under-maintenance" caused by a lack of monitoring, which increases maintenance costs and poses safety hazards. Summary of the Invention

[0008] To address the aforementioned problems, this invention aims to provide a method and monitoring device for measuring the wear of brake pads on high-speed trains.

[0009] The technical solution of the present invention is as follows:

[0010] On the one hand, a method for measuring the wear of brake pads on high-speed trains is provided, including the following steps:

[0011] S1: Multiple non-contact wear monitoring devices are installed on the brake pads of high-speed trains. The non-contact wear monitoring devices measure the distance between the brake pads and the brake disc based on TOF distance measurement technology, and the non-contact wear monitoring devices can also measure the temperature of the brake pads.

[0012] S2: Preprocess the distance data obtained by the non-contact wear monitoring device to obtain preprocessed distance data;

[0013] S3: Calculate the cutting-in and cutting-out end distance weights, braking frequency weights, and temperature weights of the non-contact wear monitoring device;

[0014] S4: Establish a wear thickness calculation model based on the cutting-in and cutting-out end distance weights, braking frequency weights, and temperature weights, and calculate the wear thickness of each friction block by combining the preprocessed distance data.

[0015] S5: Calculate the wear angle of the friction block in the area covered by the non-contact wear monitoring device based on the wear thickness.

[0016] S6: Calculate the actual contact area of ​​the friction block based on the aforementioned wear angle;

[0017] S7: Calculate the wear amount of each friction block based on the wear thickness and the actual contact area, taking into account the speed correction factor.

[0018] Preferably, in step S1, the non-contact wear monitoring device measures the distance between the brake pad and the brake disc based on a laser sensor.

[0019] Preferably, in step S2, a median filtering algorithm is used for preprocessing.

[0020] Preferably, in step S3, the cut-in / cut-out end distance weight is calculated using the following formula:

[0021] (1)

[0022] In the formula: The weights are the distances between the entry and exit points; This is the weight growth coefficient for the entry point; The coordinates are at the centerline of the brake pad; The length coordinates of the non-contact wear monitoring device on the brake pad; This is the weight growth coefficient for the cut-out end; This refers to the total length of the brake pads;

[0023] The braking frequency weight is calculated using the following formula:

[0024] (2)

[0025] In the formula: Weighted by braking frequency; This is the current braking frequency; This represents the historical average braking frequency.

[0026] The temperature weight is calculated using the following formula:

[0027] (3)

[0028] In the formula: Temperature weighting; Real-time temperature; Reference temperature; This is the highest braking temperature;

[0029] In step S4, the wear thickness calculation model is as follows:

[0030] (4)

[0031] In the formula: Let be the wear thickness of the i-th friction block; The weights are the distances between the entry and exit points; Weighted by braking frequency; Temperature weighting; The distance measured by the non-contact wear monitoring device;

[0032] In step S5, the eccentric wear angle is calculated using the following formula:

[0033] (5)

[0034] In the formula: This is the wear angle of the friction block; The distance measured by a non-contact wear monitoring device near the cutting end of the friction block; The distance measured by a non-contact wear monitoring device near the cut-out end of the friction block; The distance between two adjacent non-contact wear monitoring devices along the length of the brake pad;

[0035] In step S6, the actual contact area is calculated using the following formula:

[0036] (6)

[0037] In the formula: This represents the actual contact area of ​​the friction block; Let be the cross-sectional area of ​​the friction block; This is the coefficient for the influence of uneven wear. The load sensitivity coefficient; This represents the actual braking normal load; To design the maximum braking load;

[0038] In step S7, the wear amount is calculated using the following formula:

[0039] (7)

[0040] In the formula: This refers to wear and tear. This is the speed correction factor.

[0041] Preferably, the velocity correction factor is calculated using the following formula:

[0042] (8)

[0043] In the formula: This is the velocity enhancement coefficient; This is the current braking speed; This is the normal operating speed.

[0044] On the other hand, a device for monitoring the wear of brake pads on high-speed trains is also provided, including a non-contact wear monitoring device and a data processing module.

[0045] The non-contact wear monitoring device is used to measure the distance between the brake pad and the brake disc based on TOF ranging technology, and to measure the temperature of the brake pad;

[0046] The data processing module is used to perform the data processing operations in steps S2-S7 of any of the above-described methods for measuring the wear of high-speed train brake pads.

[0047] Preferably, the non-contact wear monitoring device includes a TOF ranging module, a temperature detection module, a wireless transmission module, and a power supply module. The TOF ranging module and the temperature detection module are respectively connected to the wireless transmission module, and the power supply module supplies power to the other modules of the non-contact wear monitoring device.

[0048] Preferably, the TOF ranging module uses a laser sensor array.

[0049] Preferably, the non-contact wear monitoring device also includes a flexible installation module, an angle adjustment module, and a high-temperature resistant protective component;

[0050] The flexible mounting module is used to fix the TOF ranging module and counteract vibration interference during train operation.

[0051] The angle adjustment module is used to adjust the angle of the TOF ranging module to ensure that the output signal of the TOF ranging module is always perpendicular to the brake pad friction surface.

[0052] The high-temperature resistant protective component is used to protect the TOF ranging module and isolate it from the high-temperature environment generated during the braking process.

[0053] Preferably, the flexible mounting module is a three-stage damping structure, comprising a primary metal spring layer, a secondary rubber vibration isolation layer, and a tertiary magnetic buffer pad.

[0054] The beneficial effects of this invention are:

[0055] This invention can measure the distance between the brake pad and the brake disc based on TOF ranging technology, obtaining accurate distance data without contact. It considers the weights of the entry and exit distance, braking frequency, and temperature, integrating multiple weights into the wear thickness calculation model. This makes the model more closely reflect the physical law that wear is more severe at the entry end during braking, and dynamically adjusts the weights according to the braking conditions, improving the accuracy of the algorithm. Furthermore, this invention corrects the contact area based on the wear angle, revising the traditional nominal geometric area to the actual contact area, effectively compensating for the influence of the wear angle and braking load on contact characteristics, and solving the problem of area calculation deviation caused by irregular surface morphology. Finally, this invention considers a speed correction factor, which can quantify the accelerating effect of high-speed energy on wear, improving the reliability of the wear calculation results. In summary, this invention enables the measurement of more accurate wear results. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 This is a three-dimensional installation schematic diagram of the high-speed train brake pad wear monitoring device of the present invention;

[0058] Figure 2 This is a front view installation schematic diagram of the high-speed train brake pad wear monitoring device of the present invention;

[0059] Figure 3 This is a three-dimensional schematic diagram of the monitoring device for monitoring the wear of high-speed train brake pads according to the present invention, installed on the brake pads.

[0060] Figure 4 This is a three-dimensional structural schematic diagram of the monitoring device for the wear of high-speed train brake pads according to a specific embodiment of the present invention;

[0061] Figure 5 This is a schematic front view of the high-speed train brake pad wear monitoring device of the present invention in a specific embodiment;

[0062] Figure 6 This is an exploded view of the flexible mounting module in a specific embodiment;

[0063] Figure 7 This is a schematic diagram of the laser ranging module in a specific embodiment;

[0064] Figure 8This is an exploded view of the angle adjustment module in a specific embodiment.

[0065] The numbers in the diagram are: 1-Brake disc, 2-Brake pad, 3-Friction block, 4-Monitoring device, 5-Clamping caliper;

[0066] 401-Wireless transmission module, 402-Flexible mounting module, 402.1-Soft magnetic pad, 402.2-Rubber vibration isolation layer, 402.3-Cross-shaped groove, 402.4-Circular through hole, 402.5-Permanent magnet, 402.6-Metal spring layer, 402.7-Mounting plate, 403-Angle adjustment module, 403.1-End cap, 403.2-Coil, 403.3-Iron core, 404-M4 mounting hole, 405-Laser ranging module, 405.1-Cover glass, 405.2-Alumina protective cover, 405.3-Heat dissipation groove. Detailed Implementation

[0067] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and technical features described in this application can be combined with each other. It should also be pointed out that, unless otherwise indicated, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terms "comprising" or "including" and similar words used in this invention refer to elements or objects preceding the word that encompass the elements or objects listed following the word and their equivalents, without excluding other elements or objects.

[0068] This invention provides a method for measuring the wear of brake pads on high-speed trains, comprising the following steps:

[0069] S1: Multiple non-contact wear monitoring devices are installed on the brake pads of high-speed trains. The non-contact wear monitoring devices measure the distance between the brake pads and the brake disc based on TOF (Time of Flight) ranging technology, and the non-contact wear monitoring devices can also measure the temperature of the brake pads.

[0070] This invention utilizes a non-contact wear monitoring device to monitor the wear of brake pads on high-speed trains. Compared to traditional mechanical probes, this device reduces wear and effectively extends the lifespan of protective components. Simultaneously, the monitoring device features intelligent low-power management, employing a timed wake-up mechanism. It periodically initiates the wear monitoring process, completes data acquisition, calculation, and storage, and then immediately enters deep sleep mode, minimizing energy consumption. While ensuring the continuity of monitoring data, it significantly improves the device's endurance and operational stability, meeting the long-term, reliable online monitoring requirements of high-speed trains.

[0071] In one specific embodiment, the non-contact wear monitoring device measures the distance between the brake pad and the brake disc using a laser sensor. In this embodiment, the laser sensor can obtain real-time and accurate thickness data by utilizing the optical path difference of the laser beam.

[0072] S2: Preprocess the distance data obtained by the non-contact wear monitoring device to obtain preprocessed distance data.

[0073] In one specific embodiment, a median filtering algorithm is used for preprocessing. Optionally, outliers with a deviation exceeding 3σ (σ is the standard deviation of the inherent noise of the laser sensor) are removed.

[0074] It should be noted that the preprocessing method in the above embodiments is only a preferred embodiment of the present invention, and other preprocessing methods in the prior art that can process outliers can also be applied to the present invention.

[0075] S3: Calculate the cutting-in and cutting-out end distance weights, braking frequency weights, and temperature weights of the non-contact wear monitoring device.

[0076] In a specific embodiment, the cut-in / cut-out distance weight is calculated using the following formula:

[0077] (1)

[0078] In the formula: The weights are the distances between the entry and exit points; This is the weight growth coefficient for the entry point; The coordinates are at the centerline of the brake pad; The length coordinates of the non-contact wear monitoring device on the brake pad; This is the weight growth coefficient for the cut-out end; This refers to the total length of the brake pads;

[0079] The braking frequency weight is calculated using the following formula:

[0080] (2)

[0081] In the formula: Weighted by braking frequency; This is the current braking frequency; This represents the historical average braking frequency.

[0082] The temperature weight is calculated using the following formula:

[0083] (3)

[0084] In the formula: Temperature weighting; The real-time temperature (i.e., the brake pad temperature measured in step S1); Reference temperature; This is the highest braking temperature;

[0085] S4: Establish a wear thickness calculation model based on the cutting-in and cutting-out end distance weights, braking frequency weights, and temperature weights, and calculate the wear thickness of each friction block by combining the preprocessed distance data.

[0086] In one specific embodiment, the wear thickness calculation model is as follows:

[0087] (4)

[0088] In the formula: Let be the wear thickness of the i-th friction block; The weights are the distances between the entry and exit points; Weighted by braking frequency; Temperature weighting; The distance measured by the non-contact wear monitoring device;

[0089] S5: Calculate the wear angle of the friction block in the area covered by the non-contact wear monitoring device based on the wear thickness.

[0090] In one specific embodiment, the wear angle is calculated using the following formula:

[0091] (5)

[0092] In the formula: This is the wear angle of the friction block; The distance measured by a non-contact wear monitoring device near the cutting end of the friction block; The distance measured by a non-contact wear monitoring device near the cut-out end of the friction block; The distance between two adjacent non-contact wear monitoring devices along the length of the brake pad;

[0093] S6: Calculate the actual contact area of ​​the friction block based on the aforementioned wear angle.

[0094] In one specific embodiment, the actual contact area is calculated using the following formula:

[0095] (6)

[0096] In the formula: This represents the actual contact area of ​​the friction block; Let be the cross-sectional area of ​​the friction block; This is the coefficient for the influence of uneven wear. The load sensitivity coefficient; This represents the actual braking normal load; To design the maximum braking load;

[0097] S7: Calculate the wear amount of each friction block based on the wear thickness and the actual contact area, taking into account the speed correction factor.

[0098] In one specific embodiment, the wear amount is calculated using the following formula:

[0099] (7)

[0100] In the formula: This refers to wear and tear. This is the speed correction factor.

[0101] In one specific embodiment, the velocity correction factor is calculated using the following formula:

[0102] (8)

[0103] In the formula: This is the velocity enhancement coefficient; This is the current braking speed; This is the normal operating speed.

[0104] In one specific embodiment, after the train monitoring system receives the wear data measured by this invention, it analyzes the wear trend using a built-in time-series prediction model to generate wear prediction data for the next 72 hours. When the prediction result reaches a preset replacement threshold, the system automatically combines information such as vehicle scheduling plans and maintenance resource allocation to generate a maintenance work order containing the specific location, model, estimated replacement time, and priority of the brake pads. An early warning signal can be sent when any of the following conditions occur: the cumulative wear of the friction material reaches 60% of the initial volume; the real-time thickness of a single friction block is less than 50% of the initial thickness; or the overall average thickness of the brake pads is less than 50% of the initial thickness.

[0105] On the other hand, the present invention also provides a device for monitoring the wear of brake pads on high-speed trains, including a non-contact wear monitoring device and a data processing module.

[0106] The non-contact wear monitoring device is used to measure the distance between the brake pad and the brake disc based on TOF ranging technology, and to measure the temperature of the brake pad;

[0107] The data processing module is used to perform the data processing operations in steps S2-S7 of any of the above-described methods for measuring the wear of high-speed train brake pads.

[0108] In a specific embodiment, such as Figure 1As shown, the monitoring device 4 is installed on the braking system, which includes a brake disc 1, brake pads 2, friction blocks 3, and calipers 5. Optionally, as... Figure 2-3 As shown, the monitoring devices 4 are symmetrically distributed on the brake pads 2, both vertically and on both sides. Ten monitoring devices 4 are arranged on a single brake pad 2, which can cover all the friction blocks 3 on the brake pad 2.

[0109] In one specific embodiment, the non-contact wear monitoring device includes a TOF ranging module, a temperature detection module, a wireless transmission module, and a power supply module. The TOF ranging module and the temperature detection module are respectively connected to the wireless transmission module, and the power supply module supplies power to the other modules of the non-contact wear monitoring device. Optionally, the TOF ranging module uses a laser sensor array.

[0110] In one specific embodiment, the wireless transmission module employs Wi-Fi 6 and LTE-M communication protocols. During operation, the module prioritizes the 5GHz high-frequency band of Wi-Fi 6 for short-range, high-speed data transmission within the train carriages, adding a CRC-32 checksum to each data packet to ensure data integrity. LTE-M serves as a backup, ensuring no data loss in the event of a single link failure during cross-carriage or cross-train data transmission. In this dual-communication protocol operating mode, the wireless transmission module can simultaneously meet the requirements of real-time monitoring of brake pad wear, data backup, and aggregation. Furthermore, the wireless transmission module can be equipped with an aluminum alloy shielding shell, effectively shielding against electromagnetic interference during train operation.

[0111] In the above embodiments, a wireless transmission module supporting both Wi-Fi 6 and LET-M modes is adopted, which is compatible with the existing train monitoring system and can upload data such as wear angle, wear thickness, and wear amount in real time, solving the problems of complex wiring and reliability of traditional wired connections.

[0112] In one specific embodiment, the non-contact wear monitoring device further includes a flexible mounting module, an angle adjustment module, and a high-temperature resistant protective component;

[0113] The flexible mounting module is used to fix the TOF ranging module and counteract vibration interference during train operation.

[0114] The angle adjustment module is used to adjust the angle of the TOF ranging module to ensure that the output signal of the TOF ranging module is always perpendicular to the brake pad friction surface.

[0115] The high-temperature resistant protective component is used to protect the TOF ranging module and isolate it from the high-temperature environment generated during the braking process.

[0116] In the above embodiments, the angle adjustment module can also be linked with the wireless transmission module to transmit the wear angle data to the data processing module in real time, and generate an "angle-wear" correlation curve by combining the ranging value to monitor the wear status of the brake pad.

[0117] In a specific embodiment, such as Figure 4-5 As shown, the non-contact wear monitoring device includes a wireless transmission module 401, a flexible installation module 402, an angle adjustment module 403, an M4 mounting hole 404, and a laser ranging module 405.

[0118] like Figure 6 As shown, the flexible mounting module 402 has a three-stage damping structure, including a primary metal spring layer 402.6, a secondary rubber vibration isolation layer 402.2, and a tertiary magnetic buffer pad. The magnetic buffer pad includes a permanent magnet 402.5, a soft magnetic pad 402.1, and a mounting plate 402.7. The rubber vibration isolation layer 402.2 has a cross-shaped groove 402.3 and a circular through hole 402.4. The permanent magnet 402.5 is made of neodymium iron boron and has a thickness of 1 mm; the soft magnetic pad 402.1 is made of low-carbon steel and has a thickness of 1 mm. The two are separated by a 4 mm thick rubber vibration isolation layer 402.2 to form a 4 mm air gap. When the train brakes, the vibration and impact generated by the braking system are transmitted to the brake pads. The air gap changes dynamically, and the magnetic attraction force is automatically adjusted, thereby achieving a shock absorption effect.

[0119] The rubber vibration isolation layer 402.2 is made of high-performance hydrogenated nitrile rubber, with a temperature resistance of -40°C to +150°C, to meet the long-term service requirements of braking environments. Simultaneously, cross-shaped through grooves with a depth of 1 mm and a width of 2 mm are formed along the thickness direction, creating an orthogonal flexible hinge structure. Furthermore, the rubber vibration isolation layer 402.2 also has circular through holes with a diameter of 1 mm and a spacing of 2 mm between each hole to absorb vibration energy.

[0120] The 402.6 metal spring layer is made of 50CrVA spring steel with a composite coating on the surface, which significantly improves fatigue resistance. This layer has four sets of springs, located at the four corners of the mounting plate, with spacings of 10 mm and 12 mm respectively. The initial pre-compression of the springs is 2 mm to eliminate initial vibration response delay. The layers are connected using M4 screws to secure them to the brake pad backplate.

[0121] like Figure 7As shown, the angle adjustment module 403 is an electromagnet assembly arranged on the mounting plate 402.7 of the flexible mounting module 402. The electromagnet assembly includes four sets of electromagnets with a diameter of 4 mm, arranged at the four corners of the mounting plate 402.7. The electromagnet includes an end cap 403.1, a coil 403.2, and an iron core 403.3. It can form a magnetic coupling linkage structure with the permanent magnet of the magnetic buffer pad. By controlling the magnitude of the coil current, the electromagnetic force is changed, driving the mounting plate 402.7 to tilt ±5° around the central fulcrum of the magnetic buffer pad, ensuring that the laser beam is always perpendicular to the friction surface of the brake pad.

[0122] like Figure 8 As shown, the laser ranging module 405 includes a laser emitter and receiver and a high-temperature resistant protective component. The laser emitter and receiver adopt a straight-slot design with a built-in cover glass 405.1 that provides optical filtering for the module and prevents wear debris from entering. The high-temperature resistant protective component includes a high-purity alumina protective cover 405.2 to prevent interface stress cracking at high temperatures, and also features a 2 mm wide heat dissipation groove 405.3 to improve the component's heat dissipation efficiency. The outer surface of the protective cover is coated with a silicon carbide coating, and the inner surface is coated with a thermally conductive silicone layer, achieving an absorption rate of ≥90% for 2-15μm infrared thermal radiation. A temperature sensor (i.e., a temperature detection module) is installed within the laser ranging module to provide temperature compensation parameters.

[0123] In the above embodiments, a three-stage damping elastic shock absorber bracket (metal spring + rubber vibration isolation layer + magnetic buffer pad) and an angle adjustment mechanism linked to an electromagnet assembly are used to ensure the measurement stability of the laser ranging module in a high-frequency vibration environment, solving the problems of optical path offset and vibration noise caused by traditional rigid installation. The magnetically coupled linkage adjustment system composed of the magnetic buffer structure and the electromagnet provides dynamic and controllable angle adjustment capability while satisfying shock absorption, breaking through the technical bottlenecks of response lag and poor low-frequency adjustment accuracy of existing passive adjustment structures.

[0124] Through the composite protective structure of alumina ceramic protective cover and thermally conductive silicone layer, the internal sensor operating temperature remains stable below 80°C when the brake disc friction surface temperature reaches 600°C, breaking through the performance drift bottleneck of existing devices in high-temperature scenarios, and maintaining a laser transmittance of over 95%.

[0125] In a specific embodiment, taking a CR400AF high-speed train as an example, the brake pad wear of the high-speed train is measured using the method for measuring brake pad wear of the present invention, which specifically includes the following steps:

[0126] (1) The initial thickness of the brake pads was measured using ground-based tooling, and multiple non-contact wear monitoring devices were installed on the brake pads;

[0127] (2) Use the angle adjustment mechanism to drive the laser ranging module for initial calibration, adjust the current of the inner coil of the electromagnet, drive the mounting plate to rotate at a speed of 1° / s, so that the laser beam is projected vertically onto the friction surface of the brake disc.

[0128] (3) The laser emitter emits a 905 nm laser pulse, which is reflected by the friction surface of the brake disc and captured by the laser receiver. The distance between the brake pad and the brake disc is calculated by the TOF method (formula: d=c×t / 2, where c is the speed of light and t is the time of flight). The measurement time of a single laser ranging module is ≤30 ms.

[0129] (4) The data measured by the laser ranging module is preprocessed by the median filtering algorithm to remove outliers with deviations exceeding 3σ (σ is the standard deviation of the sensor’s inherent noise) and obtain the preprocessed distance data.

[0130] (5) Calculate the cutting-in and cutting-out end distance weights, braking frequency weights, and temperature weights according to equations (1)-(3);

[0131] (6) Establish the wear thickness calculation model shown in equation (4), and calculate the wear thickness of each friction block in combination with the preprocessed distance data;

[0132] (7) Calculate the wear angle of the friction block in the area covered by the non-contact wear monitoring device according to formula (5);

[0133] (8) Calculate the actual contact area of ​​the friction block according to formula (6);

[0134] (9) Calculate the wear amount of each friction block according to formulas (7)-(8).

[0135] In this embodiment, the brake pad has hexagonal perforated friction blocks with an initial thickness of 20 mm, a side length of 12.7 mm, and an inner hole diameter of 8 mm, totaling 17 friction blocks.

[0136] Three wear monitoring devices are arranged on each of the upper and lower edges of a single brake pad backplate (6 in total), and four wear monitoring devices are symmetrically arranged along the central axis, for a total of 10 wear monitoring devices on each brake pad, forming a symmetrical measurement matrix on both sides. The sensor spacing is 30 mm along the length direction and 40 mm along the width direction, covering all 17 friction blocks.

[0137] Taking the third friction block as an example, the unweighted wear thickness H at the cutting end measured by the sensor is 7.5 mm, the sensor spacing L is 30 mm, the coordinate x3 of the friction block along the length of the brake pad is 290 mm, the coordinate x0 of the brake pad's central axis is 200 mm, and the cutting end weighting coefficient is... If we take 0.8, then its position weight is:

[0138] (9)

[0139] Current braking frequency The historical average braking frequency is 12. If the value is 11, then the braking frequency weight is:

[0140] (10)

[0141] The wear monitoring device has a built-in temperature sensor that measures the real-time temperature. The reference temperature is 210℃. The highest braking temperature is 25℃. If the temperature is 500℃, then the temperature weighting is:

[0142] (11)

[0143] The weighted wear thickness at the cut end measured by the sensor is then:

[0144] (12)

[0145] The same algorithm can be used to obtain the weighted wear thickness at the cut end. It is 7.65 mm;

[0146] Then the grinding angle is:

[0147] (13)

[0148] The angle adjustment mechanism adjusts the coil current according to the θ-driven electromagnet group, tilting the mounting plate by 3.031° to ensure that the laser beam is perpendicularly incident on the brake disc.

[0149] Friction block cross-sectional area S geo It is 369.26 mm. 2 Actual braking normal load The design maximum braking load is 85 kN. The load sensitivity coefficient is 150 kN. Take 0.2 as the influence coefficient of uneven wear. Taking 0.5, the actual contact area is:

[0150] (14)

[0151] Speed ​​enhancement coefficient The current braking speed is 0.05. The speed is 160 km / h, which is the normal operating speed. If the speed is 120 km / h, then the speed correction factor is:

[0152] (15)

[0153] The wear amount of the third friction block was calculated:

[0154] (16).

[0155] In summary, this invention can more accurately measure the wear of brake pads on high-speed trains. Compared with the prior art, this invention represents a significant advancement.

[0156] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for measuring the wear amount of a brake pad of a high-speed train, characterized by, Includes the following steps: S1: Multiple non-contact wear monitoring devices are installed on the brake pads of high-speed trains. The non-contact wear monitoring devices measure the distance between the brake pads and the brake disc based on TOF distance measurement technology, and the non-contact wear monitoring devices can also measure the temperature of the brake pads. S2: Preprocess the distance data obtained by the non-contact wear monitoring device to obtain preprocessed distance data; S3: Calculate the cutting-in / cutting-out end distance weight, braking frequency weight, and temperature weight of the non-contact wear monitoring device; the cutting-in / cutting-out end distance weight is calculated using the following formula: （1） In the formula: The weights are the distances between the entry and exit points; This is the weighting coefficient for the entry point; The coordinates are at the centerline of the brake pad; The length coordinates of the non-contact wear monitoring device on the brake pad; This is the weight growth coefficient for the cut-out end; This refers to the total length of the brake pads; The braking frequency weight is calculated using the following formula: （2） In the formula: Weighted by braking frequency; This is the current braking frequency; This represents the historical average braking frequency. The temperature weight is calculated using the following formula: （3） In the formula: Temperature weighting; Real-time temperature; Reference temperature; This is the highest braking temperature; S4: Establish a wear thickness calculation model based on the cutting-in / cut-out end distance weight, braking frequency weight, and temperature weight, and calculate the wear thickness of each friction block by combining the preprocessed distance data; the wear thickness calculation model is as follows: （4） In the formula: Let be the wear thickness of the i-th friction block; The weights are the distances between the entry and exit points; Weighted by braking frequency; Temperature weighting; The distance measured by the non-contact wear monitoring device; S5: Calculate the wear angle of the friction block in the area covered by the non-contact wear monitoring device based on the wear thickness. S6: Calculate the actual contact area of ​​the friction block based on the aforementioned wear angle; S7: Calculate the wear amount of each friction block based on the wear thickness and the actual contact area, taking into account the speed correction factor.

2. The method for measuring the wear of brake pads on high-speed trains according to claim 1, characterized in that, In step S1, the non-contact wear monitoring device measures the distance between the brake pads and the brake disc based on a laser sensor.

3. The method for measuring the wear of brake pads on high-speed trains according to claim 1, characterized in that, In step S2, a median filtering algorithm is used for preprocessing.

4. The method for measuring the wear of brake pads on high-speed trains according to claim 1, characterized in that, In step S5, the eccentric wear angle is calculated using the following formula: （5） In the formula: This refers to the wear angle of the friction block; The distance measured by a non-contact wear monitoring device near the cutting end of the friction block; The distance measured by a non-contact wear monitoring device near the cut-out end of the friction block; The distance between two adjacent non-contact wear monitoring devices along the length of the brake pad; In step S6, the actual contact area is calculated using the following formula: （6） In the formula: This represents the actual contact area of ​​the friction block; Let be the cross-sectional area of ​​the friction block; This is the coefficient for the influence of uneven wear. The load sensitivity coefficient; This represents the actual braking normal load; To design the maximum braking load; In step S7, the wear amount is calculated using the following formula: （7） In the formula: This refers to wear and tear. This is the speed correction factor.

5. The method for measuring the wear of high-speed train brake pads according to claim 4, characterized in that, The velocity correction factor is calculated using the following formula: （8） In the formula: This is the velocity enhancement coefficient; This is the current braking speed; This is the normal operating speed.

6. A device for monitoring the wear of brake pads on high-speed trains, characterized in that, Includes a non-contact wear monitoring device and a data processing module; The non-contact wear monitoring device is used to measure the distance between the brake pad and the brake disc based on TOF ranging technology, and to measure the temperature of the brake pad; The data processing module is used to implement the data processing operations in steps S2-S7 of the method for measuring the wear of brake pads of high-speed trains according to any one of claims 1-5.

7. The monitoring device for the wear of brake pads on high-speed trains according to claim 6, characterized in that, The non-contact wear monitoring device includes a TOF ranging module, a temperature detection module, a wireless transmission module, and a power supply module. The TOF ranging module and the temperature detection module are respectively connected to the wireless transmission module, and the power supply module supplies power to the other modules of the non-contact wear monitoring device.

8. The monitoring device for the wear of high-speed train brake pads according to claim 7, characterized in that, The TOF ranging module uses a laser sensor array.

9. The monitoring device for the wear of high-speed train brake pads according to claim 7 or 8, characterized in that, The non-contact wear monitoring device also includes a flexible installation module, an angle adjustment module, and a high-temperature resistant protective component; The flexible mounting module is used to fix the TOF ranging module and counteract vibration interference during train operation. The angle adjustment module is used to adjust the angle of the TOF ranging module to ensure that the output signal of the TOF ranging module is always perpendicular to the brake pad friction surface. The high-temperature resistant protective component is used to protect the TOF ranging module and isolate it from the high-temperature environment generated during the braking process.

10. The monitoring device for the wear of brake pads on high-speed trains according to claim 9, characterized in that, The flexible mounting module has a three-stage damping structure, including a primary metal spring layer, a secondary rubber vibration isolation layer, and a tertiary magnetic buffer pad.

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