A wheel set diameter online measuring device and measuring method thereof

Abstract

The present invention relates to the technical field of online dimension measurement of train wheelsets, and in particular to an online wheel diameter measuring device and a measuring method thereof. Its technical solution includes: a first laser sensor and a second laser sensor for measuring wheelsets; the first laser sensor is installed at a certain angle on the inner side or the outer side of the wheel, and the second laser sensor is installed at a certain angle on the outer side of the wheelset tread. The first laser sensor and the second laser sensor are both fixedly installed by a fixing mechanism. The present invention uses laser ranging technology and only needs to perform a series of operations on the digital data measured by the sensor. The data processing algorithm is simple and lightweight, has low requirements on the computing power of the on-site industrial control computer, and has a fast calculation response; compared with basic offline measurement, it has the advantages of no need to disassemble the wheelset and high efficiency of immediate measurement; compared with mainstream wheel diameter online measurement methods, it has the advantages of higher accuracy, convenient calibration, and less weather influence.

Description

Technical Field

[0001] The present invention relates to the technical field of online dimension measurement of train wheelsets, and in particular to an online wheelset diameter measurement device and a measurement method thereof. Background Art

[0002] The wheelset is the part of a rolling stock that contacts the rails. It consists of two wheels securely mounted on a single axle. As a crucial component of the running gear of rail transit vehicles such as high-speed trains, EMUs, and subways, the wheelset bears the vehicle's entire load and impact, guides the vehicle along the rails at high speed, and generates traction or braking force through adhesion with the rails. As urban rail speeds continue to increase, mileage increases, and loads increase, wheelset wear intensifies.

[0003] The circumferential surface of a train wheel set consists of two functional curved surfaces: the wheel flange and the tread. The tread contacts the rails for load-bearing operation and, together with the wheel flange, serves as a guide. Therefore, any surface area of ​​the wheel set that contacts the rails will experience wear. Only the arc at the top of the wheel flange, which does not contact the rail, experiences no wear and maintains stable geometric dimensions during operation.

[0004] When wheel tread wear reaches a certain level, the wheel must be reground to remove the damaged area. However, regrounding reduces the wheel's rolling circle diameter. Changes in wheel diameter can cause changes in the primary suspension, affecting vehicle speed, cornering ability, and comfort. Currently, wheel diameter measurement relies primarily on manual inspection, which is not very accurate. Summary of the Invention

[0005] The purpose of the present invention is to address the problems existing in the background technology and propose an online wheel diameter measurement device and a measurement method thereof, which performs a series of operations on digital data measured by a sensor and has a simple and lightweight data processing algorithm.

[0006] The technical solution of the present invention is: an online wheel set diameter measuring device and a measuring method thereof, comprising a first laser sensor and a second laser sensor for measuring the wheel set;

[0007] The first laser sensor is installed at a certain angle on the inner side or the outer side of the wheel, and the second laser sensor is installed at a certain angle on the outer side of the wheelset tread.

[0008] Preferably, the first laser sensor and the second laser sensor are both fixedly installed by a fixing mechanism.

[0009] Another technical solution of the present invention is an online wheel diameter measurement method, which utilizes the above-mentioned measuring device and includes the following steps:

[0010] S100: Detecting a wheelset using a first laser sensor and a second laser sensor, measuring and storing profile data;

[0011] S200: cleaning the measured profile data;

[0012] S300: Obtaining a vertical height difference based on the profile data of the axle surface;

[0013] S400: Finding the contact point based on the tread profile data and the axle cross-section profile data;

[0014] S500: Calculating the vertical distance between the plane where the contact point 5 is located and the measurement plane 6 and the distance between the contact point and the laser sensor point of the measurement axle;

[0015] S600: obtaining actual wheel diameter;

[0016] S700: Output wheelset diameter report.

[0017] Preferably, in S100, before the first laser sensor and the second laser sensor measure, a proximity sensor is used to detect whether a wheelset passes by, and the first laser sensor and the second laser sensor are controlled by PLC to start working according to the monitoring results, and the axle cross-sectional profile and wheelset tread profile data are stored in the order of passing.

[0018] Preferably, the cleaning of the measurement profile data includes removing peaks, erroneous points and smoothing mean filtering.

[0019] Preferably, in S300, an algorithm is used to complete the cross-sectional profile of the axle, find the geometric center position corresponding to the cross-section, and calculate the vertical height difference ΔH between the position coordinates and the measurement point A of the first laser sensor.

[0020] Preferably, in said S400, a matching operation is performed based on the on-site rail geometry and the measured tread profile data to obtain the contact point between the wheelset and the track.

[0021] Preferably, in said S500, the distance between said contact point and the first laser sensor point measuring the axle is ΔL1;

[0022] The measuring plane is 70 mm away from the inner side of the wheel. The compensation value is the distance between the contact point and the measuring plane, which is △L2.

[0023] Calculate △L1+△L2=△L as the error to be compensated.

[0024] Preferably, the actual wheel diameter is obtained in the following manner:

[0025] Subtract the compensation error △L in the previous step from the calculated vertical height difference △H between the geometric center position and the sensor center, and multiply it by 2 to obtain the actual wheel diameter.

[0026] Preferably, in said S100, a guide device is introduced to limit the left and right swing amplitude of the wheel during serpentine motion.

[0027] Compared with the prior art, the present invention has the following beneficial technical effects:

[0028] The present invention uses laser ranging technology and only needs to perform a series of operations on the digital data measured by the sensor. The data processing algorithm is simple and lightweight, the requirements for the computing power of the on-site industrial control computer are low, and the calculation response is fast;

[0029] Compared with basic offline measurement, it has the advantages of no need to disassemble the wheelset and high efficiency of immediate measurement. Compared with mainstream wheel diameter online measurement methods, it has the advantages of higher accuracy (up to ±0.2mm), convenient calibration, and less impact by weather. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A schematic diagram of the overall installation layout structure of an embodiment of the present invention is provided;

[0032] Figure 2 A side view of the online wheel diameter measurement method of the present invention;

[0033] Figure 3 This is a partially enlarged schematic diagram of the calculation error compensation of the present invention;

[0034] Figure 4 Schematic diagram of the installation structure of the first laser sensor and the second laser sensor of the present invention;

[0035] Figure 5 This is a flow chart of an online wheel diameter measurement method of the present invention;

[0036] Figure numerals: 1 first laser sensor; 2 second laser sensor; 3 geometric center position of the axle cross section; 4 position coordinates and measurement point A of the first laser sensor; 5 contact point between the wheelset and the tread during travel; 6 measurement plane; 7 measurement point B of the first laser sensor measuring the axle; 8 fixing mechanism. DETAILED DESCRIPTION

[0037] The technical solution of the present invention is further described below with reference to the accompanying drawings and specific embodiments. Example 1

[0038] like Figure 1 and Figure 2 As shown, the present invention proposes an online wheel diameter measuring device, comprising a first laser sensor 1 and a second laser sensor 2 for measuring the wheel diameter;

[0039] The first laser sensor 1 is mounted at an angle on the inside or outside of the wheel, and the second laser sensor 2 is mounted at an angle on the outside of the wheelset tread. The first laser sensor 1 measures the outer contour of the exposed portion of the axle near the wheels on both sides, while the second laser sensor 2 measures the contour of the wheelset tread.

[0040] like Figure 1 As shown in Figure 1 The figure schematically shows two installation methods of the first laser sensor 1. In actual use, only one of the installation positions needs to be selected for installation. The figure only shows the installation on the right side. The installation on the left side is symmetrical to the right side. At the same time, a proximity sensor is installed in front of the measuring wheel to trigger the measurement program; refer to Figure 4 The first laser sensor 1 and the second laser sensor 2 are both fixedly installed by a fixing mechanism 8.

[0041] The first laser sensor 1 and the second laser sensor 2 can be fixed to the sleeper by using a fixing mechanism 8, wherein the fixing mechanism 8 includes a mounting bracket and a fixing bolt, wherein the mounting bracket is used to fix the first laser sensor 1 and the second laser sensor 2, and the fixing bolt is used to fix the mounting bracket, and the mounting bracket used to fix the second laser sensor 2 matches its installation inclination angle;

[0042] The working principle of an online wheelset diameter measurement device based on Example 1 is as follows: a total of four line laser sensors on both sides of the track are connected to the PLC, and the measurement and storage of the profile data are controlled by the PLC; the first laser sensor 1 and the second laser sensor 2 can be fixed by the fixing mechanism 8, and the proximity sensor is used to measure in advance whether the wheelset is measured. When a wheelset is detected passing, the PLC is used to control the first laser sensor 1 and the second laser sensor 2 to start working according to the monitoring results, and the wheelset profile data is stored and measured in the order of passing. Example 2

[0043] Reference Figure 1-5 As shown, based on the first embodiment, the present invention further proposes an online wheel diameter measurement method, which uses the measuring device in the first embodiment and includes the following steps:

[0044] S100: Detecting the wheelset using the first laser sensor 1 and the second laser sensor 2, measuring and storing profile data;

[0045] In S100, before the first laser sensor 1 and the second laser sensor 2 perform measurement, a proximity sensor is used to detect whether a wheelset has passed by, and the first laser sensor 1 and the second laser sensor 2 are controlled by a PLC to start working based on the monitoring result, and the axle cross-sectional profile and wheelset tread profile data are stored in the order of passing by;

[0046] At the same time, in S100, a guide device is introduced to limit the left and right swing amplitude of the wheel during serpentine motion. Since the serpentine motion of the vehicle on the track will cause increased measurement errors, the introduction of a guide device to limit its left and right swing amplitude improves measurement accuracy.

[0047] S200: Cleaning the measured profile data; the cleaning of the measured profile data includes data cleaning steps such as removing peaks, error points, and smoothing mean filtering.

[0048] S300: Obtaining a vertical height difference based on the profile data of the axle surface;

[0049] In S300 , an algorithm is used to complete the cross-sectional profile of the axle, find the geometric center position corresponding to the cross-sectional profile, and calculate the vertical height difference ΔH between the position coordinates and the first laser sensor measurement point A4 of the first laser sensor 1 .

[0050] Use the algorithm to complete the outline and find the geometric center position of the axle section corresponding to the section 3 (refer to Figure 2 As shown), calculate the vertical height difference ΔH between the geometric center position 3 and the first laser sensor measurement point A4 of the first laser sensor 1;

[0051] It should be noted that in order to simplify the contour completion algorithm in this step, the laser can be kept perpendicular to the center axis of the axle as much as possible. In this way, the cross section is a standard circle, and the coordinates of the circle center can be easily obtained using the three-point circle determination algorithm.

[0052] S400: Find the contact point based on the tread profile data and the axle cross-section profile data, such as Figure 3 As shown, based on the on-site rail geometry and the measured tread profile data, a matching operation is performed to obtain the contact point between the wheelset and the track, and the tangent position between the two is calculated to obtain the contact point 5 between the wheelset and the tread during travel and its contact point coordinates;

[0053] S500: Calculating the vertical distance between the plane where the contact point 5 is located and the measurement plane 6 and the distance between the contact point and the laser sensor point of the measurement axle;

[0054] The distance between the contact point and the first laser sensor point B 7 of the measuring axle is ΔL1;

[0055] The inner side of the wheel is parallel and 70mm apart ( Figure 3 The point △L3) in the middle is the measuring plane 6, and the compensation value is the distance between the plane where the contact point is located and the measuring plane, which is △L2;

[0056] Calculate △L1+△L2=△L as the error to be compensated. This is the error to be compensated in the final calculation result.

[0057] S600: obtaining actual wheel diameter;

[0058] The specific method for obtaining the actual wheel diameter is:

[0059] Subtract the compensation error △L in the previous step from the calculated vertical height difference △H between the geometric center position 3 and the center of the first laser sensor 1, and multiply it by 2 to obtain the actual wheel diameter, that is, L=2*(△H-△L);

[0060] S700: Output wheelset diameter report. After the entire train has passed, the stop measurement switch is triggered, and the PLC stops measuring and storing data. Finally, the wheelset diameter report of the entire vehicle is output according to the template required by the user.

[0061] It is particularly important to note that, based on on-site factors such as the type of vehicles running on the line and the axle box design, the measured axle profile is guaranteed to be a regular figure that can be completed with high precision and the geometric center calculated. The installation position and angle are adjusted in real time, and various changes can be made accordingly. In particular, the number, position, and three-dimensional spatial angle of the laser sensors used to measure the contour may be adjusted due to the implementation of the line running vehicle situation.

[0062] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "disposed" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections, direct connections, or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0063] The above specific embodiments are only one or several preferred embodiments of the present invention. Based on the technical solutions of the present invention and the relevant inspiration of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A method for online measurement of wheelset diameter, utilizing a measuring device comprising a first laser sensor and a second laser sensor for measuring the wheelset; the first laser sensor being mounted at a certain angle on the inner side or outer side of the wheel, and the second laser sensor being mounted at a certain angle on the outer side of the wheelset tread; characterized in that: The steps are as follows: S100: Detecting a wheelset using a first laser sensor and a second laser sensor, measuring and storing profile data; S200: cleaning the measured profile data; S300: Using an algorithm to complete the axle cross-section profile data measured by the first laser sensor, finding the geometric center position corresponding to the cross-section, and calculating the vertical height difference ΔH between the position coordinates and the measurement point A of the first laser sensor; S400: performing a matching operation based on the on-site rail geometry and the tread profile data measured by the second laser sensor to obtain the contact point between the wheelset and the track; S500: Calculating the vertical distance between the plane where the contact point is located and the measurement plane, and the distance between the contact point and the measurement point of the laser sensor of the measuring axle. Specifically, the distance between the contact point and the first laser sensor measurement point B of the measuring axle is ΔL1. The measurement plane is 70 mm away from the inner side of the wheel. The compensation value is the distance between the contact point and the measurement plane, which is △L2. Calculate △L1+△L2=△L as the error to be compensated; S600: Obtain the actual wheel diameter by subtracting the compensation error △L obtained in the previous step from the calculated vertical height difference △H between the geometric center position and the sensor center, and multiplying the result by 2 to obtain the actual wheel diameter, i.e., L = 2 × (△H - △L). S700: Output wheelset diameter report.

2. The method for online measuring wheelset diameter according to claim 1, characterized in that: The first laser sensor and the second laser sensor are both fixedly installed by a fixing mechanism.

3. The method for online measuring wheelset diameter according to claim 1, characterized in that: In S100, before the first laser sensor and the second laser sensor measure, a proximity sensor is used to detect whether a wheelset passes by, and the first laser sensor and the second laser sensor are controlled by PLC to start working according to the monitoring results, and the axle cross-sectional profile and wheelset tread profile data are stored in the order of passing.

4. The method for online measuring wheelset diameter according to claim 1, characterized in that: The cleaning of the measured profile data includes removing peaks, error points, and smoothing and averaging filtering.

5. The method for online measuring wheelset diameter according to claim 1, characterized in that: In the above S100, a guide device is introduced to limit the left and right swing amplitude of the wheel during the serpentine motion.

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