Three-point measurement method for deflection of metro vehicle

Abstract

This invention discloses a three-point method for measuring the deflection of subway vehicles, comprising the following steps: 1. Parking the subway vehicle to be measured on the zero rail; 2. Measuring the vertical distance from multiple points on the bottom of each car of the subway vehicle to the zero rail using a level and a measuring tape; 3. Calculating the heights Y1, Y3, and Y2 of the leading end, trailing end, and center point of each car from the zero rail surface according to the following formulas; 4. Calculating the height differences HZ1 and HZ2 between the first and second bogies of each car; 5. Correcting Y1, Y3, and Y2 based on the difference between HZ1 and HZ2; 6. Repeating steps 2 to 5 to obtain Y1, Y3, and Y2 for all cars of the subway vehicle, and summing them to obtain the deflection range of the subway vehicle. This invention can measure the deflection of rail transit vehicles more accurately, and saves measurement time, improving measurement efficiency.

Description

Technical Field

[0001] This invention relates to the field of subway vehicle deflection measurement technology, and particularly to a three-point method for measuring subway vehicle deflection. Background Technology

[0002] With my country's economic development and the continuous expansion of urban areas, urban rail transit development has become an inevitable choice for alleviating traffic congestion. According to national planning, rail transit construction has been listed as a top priority in China's infrastructure development, and the country is vigorously promoting its development. The rapid development of urban rail transit is driving a leap forward in rail transit vehicle manufacturing technology.

[0003] Deflection is a crucial parameter for rail transit vehicles in addressing three key issues: strength, stiffness, and stability. During the manufacturing process, the rail transit vehicle body incorporates an upward-protruding deflection, allowing it to return to a horizontal state under the influence of gravity during operation. This ensures the vehicle body remains relatively level when subjected to vertical loads, thus extending its service life.

[0004] During the manufacturing and assembly of rail transit vehicle bodies, we need to pre-set certain deflection values ​​to ensure that the vehicle body maintains a horizontal and straight running state when under load. After the deflection values ​​are pre-set, the vehicle body needs to undergo a measurement process to check whether the deflection values ​​at specific measurement points on the vehicle body meet the standard requirements, and a certain degree of deflection value adjustment is made.

[0005] In the manufacturing and assembly process of rail transit vehicle bodies, the deflection performance index of the body is gradually being emphasized, and higher process requirements have been put forward in terms of body design, manufacturing process, and quality control.

[0006] Currently, typical deflection measurement methods at home and abroad mainly include: dial gauge measurement method, connecting tube measurement method, and optical measurement method.

[0007] The dial indicator measurement method is a contact measurement method. It consists of a dial indicator, a clamp, and a connecting device, which can directly measure the deflection of a target under load.

[0008] The method of measuring deflection using a connecting tube is also a contact measurement method. Its principle is that the pressure of the static liquids on the same horizontal plane in the connecting tubes is equal, and the liquid level difference between the deflection measurement point and the reference point in the connecting tube is the relative deflection value of the deflection measurement point.

[0009] Optical measurement mainly uses laser triangulation. Based on the angle of the linear array camera and the distance between the laser emitter and the linear array camera, the signal processor calculates the distance between the sensor and the object being measured.

[0010] Whether it's dial indicator measurement, connecting pipe deflection measurement, or optical measurement, all require specialized equipment, have high requirements for measurement personnel, are expensive, and take a long time. They present many inconveniences when actually measuring vehicle body deflection, making it difficult to meet the needs of quick and easy measurement in daily maintenance sites.

[0011] With the increasing sophistication of equipment maintenance, vehicle inspection and maintenance are becoming more comprehensive. For routes with significantly increased passenger flow during morning and evening rush hours, vehicle overloading is a prominent issue during peak periods. Long-term overloading poses a considerable challenge to the structural strength of vehicles. Therefore, routine maintenance of vehicles that have been in operation for many years requires regular monitoring of changes in vehicle body deflection.

[0012] Although on-site maintenance personnel generally have strong hands-on skills, they have limited knowledge of specific testing equipment and limited daily maintenance time. Therefore, simple, economical, practical and easy-to-use measurement methods are more suitable for vehicle maintenance.

[0013] Common deflection measurement methods, such as dial gauge measurement and connecting pipe measurement, require highly skilled personnel, take a long time, and rely heavily on the experience of the measurement personnel. In contrast, optical measurement requires keeping the laser sensor in a stable and fixed state. Furthermore, while the equipment required for optical measurement is relatively simple, it is more expensive, and subsequent processing is time-consuming, resulting in higher costs.

[0014] Therefore, how to measure the deflection of subway vehicles at a lower cost and with a simpler process has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0015] In view of the above-mentioned deficiencies of the prior art, the present invention provides a three-point measurement method for the deflection of subway vehicles. The purpose is to save measurement time, reduce errors caused by bogie height differences during the measurement process, and improve measurement efficiency while being able to measure the deflection of rail transit vehicles with relatively high accuracy.

[0016] To achieve the above objectives, this invention discloses a three-point measurement method for subway vehicle deflection, comprising the following steps:

[0017] Step 1: Park the subway car to be measured on the zero rail and complete the cleaning preparation work before measurement; the cleaning preparation work includes disconnecting the power and grounding the subway car, and confirming that there are no factors that may affect personnel safety;

[0018] Step 2: Measure the vertical distance from multiple points on the bottom of each subway car to the zero rail using a level and measuring tape; the specific points to be measured for each car are as follows:

[0019] Y1L and Y1R are the heights of the center of the long beams on the left and right sides of the forward end of each carriage from the zero rail surface.

[0020] Y3L and Y3R are the heights of the center of the long beams on the left and right sides of the rear end of each carriage from the zero rail surface.

[0021] Y2L and Y2R are the heights of the center of the long beams on the left and right sides of the center point of each carriage from the zero rail surface.

[0022] Z11L, Z11R; Z12L, Z12R are the heights of the zero rail surface at the left and right ends of the first bogie Z1 air spring plane of each car section.

[0023] Z21L, Z21R; Z22L, Z22R are the heights of the zero rail surface at the left and right ends of the front and rear ends of the Z2 air spring plane of the second bogie of each car section;

[0024] Step 3: Calculate the heights Y1, Y3, and Y2 of the forward end, the trailing end, and the center point of each carriage from the zero-track surface according to the following formulas:

[0025] Y1 = (Y1L + Y1R) / 2 + T;

[0026] Y2 = (Y2L + Y2R) / 2 + T;

[0027] Y3 = (Y3L + Y3R) / 2 + T;

[0028] Where T is the thickness of the level;

[0029] Step 4: Calculate the height values ​​HZ1 and HZ2 between the first bogie and the second bogie of each car section, using the following formula:

[0030] HZ1 = (H1Z1 + H2Z1) / 2;

[0031] HZ2 = (H1Z2 + H2Z2) / 2;

[0032] Wherein, H1Z1 = (Z11L + Z11R) / 2;

[0033] H2Z1 = (Z12L + Z12R) / 2;

[0034] H1Z2 = (Z21L + Z21R) / 2;

[0035] H2Z2 = (Z22L + Z22R) / 2;

[0036] Step 5: Correct Y1, Y3, and Y2 based on the difference between HZ1 and HZ2;

[0037] Delta = |HZ2 - HZ1|;

[0038] Y1=Y1;

[0039] Y2 = Y2 - Delta / 2;

[0040] Y3 = Y3 - Delta;

[0041] Step 6: Repeat steps 2 to 5 to obtain Y1, Y3 and Y2 of all cars in the subway vehicle, and sum them to obtain the deflection range of the subway vehicle.

[0042] The beneficial effects of this invention are:

[0043] This invention saves measurement time and reduces errors caused by bogie height differences during the measurement process, thereby improving measurement efficiency, while enabling relatively accurate measurement of the deflection of rail transit vehicles.

[0044] The measurement accuracy of this invention meets the usage requirements, reaching the mm level, and satisfies the accuracy requirements for vehicle body deflection analysis and comparison during vehicle maintenance.

[0045] This invention offers higher measurement efficiency. Existing methods for measuring vehicle deflection require technicians to spend a significant amount of time on each measurement, resulting in low efficiency. This invention is easier to understand and simpler to operate, and can greatly improve the efficiency of vehicle deflection measurement.

[0046] This invention is economical, practical, and cost-effective. Existing methods for measuring vehicle body deflection mostly rely on specialized equipment, which is inconvenient to carry and manage, and the purchase of equipment and training of personnel are also very expensive.

[0047] The tools required for this invention are general-purpose tools that can be readily available at vehicle repair stations and are easy for measurement personnel to operate, making them highly practical.

[0048] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0049] Figure 1 A schematic diagram illustrating an embodiment of the present invention is shown.

[0050] Figure 2 This diagram illustrates the distribution of points in a subway car comprising six carriages, where the vertical distance to the zero track needs to be measured.

[0051] Figure 3 This diagram illustrates a summary chart of Y1, Y3, and Y2 for six carriages in one embodiment of the present invention. Detailed Implementation

[0052] Example 1

[0053] like Figure 1 As shown, the three-point measurement method for subway vehicle deflection includes the following steps:

[0054] Step 1: Park the subway car to be measured on the zero track and complete the cleaning preparation work before measurement;

[0055] Step 2: Measure the vertical distance from multiple points on the bottom of each subway car to the zero rail using a level and measuring tape; the specific points to be measured for each car are as follows:

[0056] Y1L and Y1R are the heights of the center of the long beams on the left and right sides of the forward end of each car from the zero rail surface.

[0057] Y3L and Y3R are the heights of the center of the long beams on the left and right sides of the rear end of each car from the zero rail surface.

[0058] Y2L and Y2R are the heights of the center of the long beams on the left and right sides of the center point of each car from the zero rail surface.

[0059] Z11L, Z11R; Z12L, Z12R are the heights of the first bogie Z1 air spring plane of each car from the zero rail surface at the left and right ends of the front and rear ends.

[0060] Z21L, Z21R; Z22L, Z22R are the heights of the Z2 air spring plane of the second bogie of each car from the zero rail surface at the left and right ends of the front and rear ends of the plane.

[0061] Step 3: Calculate the heights Y1, Y3, and Y2 of each car's forward end, trailing end, and center point from the zero-track rail surface using the following formulas:

[0062] Y1 = (Y1L + Y1R) / 2 + T;

[0063] Y2 = (Y2L + Y2R) / 2 + T;

[0064] Y3 = (Y3L + Y3R) / 2 + T;

[0065] Where T is the thickness of the level;

[0066] Step 4: Calculate the height values ​​HZ1 and HZ2 between the first and second bogies of each car. The specific formula is as follows:

[0067] HZ1 = (H1Z1 + H2Z1) / 2;

[0068] HZ2 = (H1Z2 + H2Z2) / 2;

[0069] Wherein, H1Z1 = (Z11L + Z11R) / 2;

[0070] H2Z1 = (Z12L + Z12R) / 2;

[0071] H1Z2 = (Z21L + Z21R) / 2;

[0072] H2Z2 = (Z22L + Z22R) / 2;

[0073] Step 5: Correct Y1, Y3, and Y2 based on the difference between HZ1 and HZ2;

[0074] Delta = |HZ2 - HZ1|;

[0075] Y1=Y1;

[0076] Y2 = Y2 - Delta / 2;

[0077] Y3 = Y3 - Delta;

[0078] Step 6: Repeat steps 2 to 5 to obtain Y1, Y3 and Y2 of all cars in the subway car, and sum them to obtain the deflection range of the subway car.

[0079] In some embodiments, the cleaning preparation work includes de-energizing and grounding the subway car and confirming that there are no factors that could affect personnel safety.

[0080] Example 2

[0081] like Figure 2 As shown, the deflection of each car body in a 6-car train was measured. The schematic diagram of the measurement scenario is as follows. Figure 2 As shown.

[0082] After completing all carriages, summarize Y1, Y3, and Y2 to obtain the results. Figure 3 The deflection range of each car in the subway train is between 7mm and 25mm. Because the train has an aluminum alloy body, which has good ductility, the designed deflection is within... After the vehicle is in operation, the deflection of the vehicle body will gradually decrease under the action of vertical load. Therefore, the measured deflection variation range is large and consistent with the actual situation.

[0083] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A three-point measurement method for deflection of a metro vehicle; characterized in that, The method comprises the following steps: Step 1, parking the metro vehicle to be measured on the zero rail, and making cleaning preparation before measurement; Step 2, measuring the vertical distance from each car bottom of the metro vehicle to the zero rail by using a level and a tape measure; the multiple point positions required to be measured for each car are as follows: Y1L and Y1R are the heights of the center distance from the long beams under the front end of each car to the rail surface of the zero rail; Y3L and Y3R are the heights of the center distance from the long beams under the trailing end of each car to the rail surface of the zero rail; Y2L and Y2R are the heights of the center distance from the long beams under the center point of each car to the rail surface of the zero rail; Z11L and Z11R; Z12L and Z12R are the heights of the front and rear ends of each car to the rail surface of the zero rail at the left and right positions of the Z1 air spring plane of the first bogie; Z21L and Z21R; Z22L and Z22R are the heights of the front and rear ends of each car to the rail surface of the zero rail at the left and right positions of the Z2 air spring plane of the second bogie; Step 3, calculating the heights Y1, Y3 and Y2 of the front end, the trailing end and the center point of each car to the rail surface of the zero rail according to the following formulas: Y1= (Y1L+Y1R) / 2+T; Y2= (Y2L+Y2R) / 2+T; Y3= (Y3L+Y3R) / 2+T; Wherein, T is the thickness of the level; Step 4, calculating the height values HZ1 and HZ2 between the first bogie and the second bogie of each car, and the specific formulas are as follows: HZ1= (H1Z1+H2Z1) / 2; HZ2= (H1Z2+H2Z2) / 2; Wherein, H1Z1= (Z11L+Z11R) / 2; H2Z1= (Z12L+Z12R) / 2; H1Z2= (Z21L+Z21R) / 2; H2Z2= (Z22L+Z22R) / 2; Step 5, correcting Y1, Y3 and Y2 according to the difference between HZ1 and HZ2; Delta= |HZ2-HZ1|; Y1=Y1; Y2=Y2-Delta / 2; Y3=Y3-Delta; Step 6, repeating steps 2 to 5 to obtain Y1, Y3 and Y2 of all cars of the metro vehicle, and then obtaining the deflection range of the metro vehicle.

2. The deflection three-point measurement method for a subway vehicle according to claim 1, characterized in that, The cleaning preparation work includes power-off and grounding of the metro vehicle, and confirming that there is no factor affecting personnel safety.

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