Railway vehicle axle box spring similar part mistake proofing method and detection device

Abstract

The invention provides a railway vehicle axle box spring similar part mistake proofing method, which can automatically analyze and recognize the direction information of left and right parts after placement aiming at the placement position of an axle box spring jacket in a forming mold by utilizing an image recognition technology, and can determine whether the placement direction of the jacket is correct or not by comparing the direction information with preset direction information. Therefore, information errors of left and right parts of a formed product caused by wrong placement of the outer sleeve are thoroughly avoided, and the product yield of the axle box spring is improved.

Description

Technical Field

[0001] The invention relates to the field of rail vehicle axle box spring manufacturing, and in particular to a rail vehicle axle box spring similar parts error prevention method and detection device. Background Art

[0002] The axle box spring is a vibration-damping element made of a metal jacket, a partition, a core shaft and rubber vulcanization. As one of the key components of the bogie of a high-speed EMU, it can not only store and release energy, but also plays an important role in achieving connection, positioning, and alleviating vibrations and impacts caused by uneven routes. It guarantees the dynamic performance and running quality of high-speed trains to a great extent. In the manufacturing process of the axle box spring, it is necessary to use molding equipment and cooperate with the corresponding vulcanization molding molds to mold the materials (iron parts, rubber materials, etc.). In the existing production molds, the same pair of molds can produce two types of axle box springs. The two types of axle box springs are exactly the same in terms of iron parts, rubber materials, and production processes. There are only problems with the positioning of the jacket and the matching of the product number. The current production process is only confirmed by the operator, and the influence of human factors cannot be avoided, resulting in problems such as mixing and difficulty in subsequent product delivery. The mold structure is as follows: Figure 1 In order to use a set of molds to produce axle box springs with different directions for left / right parts, the cavity of the forming mold 2 has four connecting ear cavities 21 to accommodate the connecting ears 12 of the outer sleeve 11 placed during forming. When the outer sleeve 11 is placed in the cavity of the forming mold 2, the connecting ears 12 will be accommodated in two opposite connecting ear cavities 21. The placement of the connecting ears 12 indicates the left and right directions of the axle box spring after forming. For example Figure 2 Schematic diagram showing the placement position and placement method of the outer sleeve 11 when the axle box springs of the left and right parts are formed.

[0003] In the molding equipment and operation method in the prior art, the left and right parts of the axle box spring need to be manually marked on the material to place the left and right parts in the wrong position, but it is still difficult to avoid the left and right parts of the axle box spring after molding being in the opposite direction due to the wrong placement of the outer sleeve 11. Often, the production requirement is the right part, but due to the manual placement of the material, the axle box spring produced is the left part, which leads to the problem that the molded product and the product number cannot correspond.

[0004] Through searching, no technical literature on the method or device for detecting similar parts of axle box springs has been found in the prior art. The prior art literature with certain relevance is the invention patent publication document with the publication number "CN112132824A" and the name "A method for automatically detecting faults of axle box springs of trucks". A method for automatically detecting faults of axle box springs of trucks is disclosed, which belongs to the field of truck operation technology. The present invention is to solve the problem that the accuracy and stability of fault detection of axle box springs of trucks by using manual detection images are not high, and the driving safety of trucks cannot be ensured. The method of the present invention comprises: building a 3D high-definition imaging device around the track, and obtaining a height image and a grayscale image after the truck passes through the device; using hardware wheelbase information combined with prior knowledge to roughly locate the axle box spring component in the image; after performing height image correction, using image processing methods to identify the axle box spring vehicle model and then accurately locate the axle box spring; using advanced image processing algorithms and pattern recognition methods to analyze the fault of the axle box spring to determine whether it has a flaring or breaking fault; uploading an alarm to the axle box spring component with a fault, and the staff performs corresponding processing according to the recognition result. This comparative document uses visual image recognition technology to automatically detect axle box spring component failures, and is not applicable to the detection of the left and right parts of the axle box spring. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a method for preventing errors of similar parts of axle box springs of railway vehicles, comprising the following steps: Step S1, obtaining product information of the axle box spring to be formed, wherein the product information at least includes predetermined left / right piece information of the axle box spring; Step S2, placing the material of the outer shell iron part including the axle box spring in a forming mold, and making the bottom surface of the outer shell of the axle box spring face upward; Step S3, deploying an image acquisition device to obtain an image including the jacket and the molding die; Step S4, processing and analyzing the image, and determining actual left / right piece information when the jacket is placed in the molding die according to the analysis result; Step S5, comparing the actual left / right piece information of the jacket with the predetermined left / right piece information of the axle box spring obtained from the product information, and returning a correct material placement if they match, otherwise returning a placement error.

[0006] Furthermore, in step S4, the acquired image is processed and analyzed, and the connecting ear on the bottom surface of the outer sleeve in the image is used as an identification mark of the actual left / right component information, and the actual left / right component information of the axle box spring is judged and confirmed based on the identification mark.

[0007] Further, an identification area S is determined in the acquired image, and it is determined whether the connecting ear appears in the identification area S to determine the actual left / right piece information of the axle box spring.

[0008] Furthermore, in the acquired image, an identification area S1 is defined based on one of the unidirectional connecting ear cavities. When the axle box spring is placed in the molding die in the left or right direction, at least one connecting ear may appear in the identification area S1.

[0009] Alternatively, in the acquired image, an identification area S2 is defined based on two opposite connecting ear cavities, and when the axle box spring is placed in the molding die in the left or right direction, at least one connecting ear may appear in the identification area S2.

[0010] Alternatively, the geometric axis L1 of the bottom surface of the outer sleeve is determined in the acquired image, and the geometric center line L2 of the connecting ears on the bottom surface of the outer sleeve is determined according to the position of the connecting ears in the image; based on the position of the geometric center line L2 relative to the geometric axis L1, the actual left / right part information of the axle box spring is determined.

[0011] Furthermore, the geometric axis L1 is determined according to the bottom surface contour of the jacket in the acquired image or according to the image information of the molding die in the acquired image.

[0012] A rail vehicle axle box spring similar parts detection device is also proposed, including a base bracket that can be connected to the top of the axle box spring forming equipment, an X-axis telescopic mechanism is connected to the base bracket, one end of the X-axis telescopic mechanism is connected to a first mounting plate, and an image acquisition unit is connected to the first mounting plate.

[0013] Furthermore, the first mounting plate is connected to an image acquisition unit via a lifting mechanism, and a fill light unit is connected to the bottom of the base bracket.

[0014] Furthermore, a protective cover is hinged at the end of the base bracket, and the protective cover is an arc-shaped cover body, which is located directly in front of the image acquisition unit.

[0015] Compared with the prior art, the technical solution of the present application has the following beneficial effects: the detection method proposed by the present invention uses image recognition technology to automatically analyze and identify the left and right part direction information after placement based on the placement position of the axle box spring jacket in the forming mold, and by comparing it with the predetermined direction information, it can be determined whether the placement direction of the jacket is correct. This completely avoids the error in the left and right part information of the product after molding due to the wrong placement of the jacket, and improves the product yield of the axle box spring. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 : Physical picture of the placement of the outer jacket in the forming mold; Figure 2: Schematic diagram of the placement of the outer jacket in the molding die; Figure 3 : Schematic diagram of the identification area provided in Example 1; Figure 4 : Schematic diagram of the identification area provided in Example 2; Figure 5 : Schematic diagram for determining the geometric axis L1 and the geometric center line L2 provided in Example 3; Figure 6 : Schematic diagram for determining the geometric axis L1 and the geometric center line L2 provided in the fourth embodiment; Figure 7 : Schematic diagram of the installation of the detection device provided in Example 5 on the molding equipment; Figure 8 : A schematic diagram of the structure of the detection device provided in Example 5; Fig. 9 : Schematic diagram of the detection device provided in Example 5 omitting the protective cover structure. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] A method for preventing errors of similar parts of a rail vehicle axle box springs comprises the following steps: Step S1, obtaining product information of the axle box spring 1 to be formed, wherein the product information at least includes predetermined left / right piece information of the axle box spring 1; Step S2, placing the material including the outer sleeve 11 of the axle box spring 1 into the forming mold 2, with the bottom surface of the outer sleeve 11 of the axle box spring 1 facing upward; Step S3, deploying an image acquisition device to acquire an image including the jacket 11 and the molding die 2; Step S4, processing and analyzing the image, and determining actual left / right piece information when the jacket 11 is placed in the molding die 2 according to the analysis result; Step S5, comparing the actual left / right piece information of the outer sleeve 11 with the predetermined left / right piece information of the axle box spring 1 obtained from the product information, and returning a correct material placement if they match, otherwise returning a placement error.

[0019] In this embodiment, the product information of the axle box spring 1 to be formed is determined, and the acquisition method can be sent by the MES system in the production line, or by scanning the information code on the material to determine the predetermined left / right part information required for this round of production. The image acquisition device uses a high-resolution camera known in the prior art. The preferred deployment method should be to allow its viewing direction to face the top of the forming mold 2 as much as possible, so that as much as possible, for example, Figure 1 The image includes the jacket 11 and the forming mold 2. When processing and analyzing the image, the image processing techniques such as color extraction, lighting correction, binary conversion, etc. in the prior art can be used to correct and process the acquired image as much as possible, so as to facilitate subsequent analysis to obtain the actual left / right piece information.

[0020] In the actual production process, the return result of step S5 plays a key role in the entire production process. When the return material is placed correctly, the molding die 2 can be normally advanced to start the subsequent molding process; if the return is placed incorrectly, the advanced die should be locked immediately to prompt the operator to check the placement of the jacket 11. The verification should continue to perform the image acquisition review in step S3 until the return material is placed correctly after step S5 is executed.

[0021] The following describes how to determine the actual left / right piece information when the outer cover 11 is placed in the molding die 2 in step S4 through different embodiments.

[0022] Embodiment 1: Figure 2 shown.

[0023] In step S4, the acquired image is processed and analyzed, and the connecting ear 12 on the bottom surface of the outer sleeve 11 in the image is used as an identification mark of the actual left / right component information, and the actual left / right component information of the axle box spring 1 is judged and confirmed based on the identification mark. An identification area S is determined in the acquired image, and it is determined whether the connecting ear 12 appears in the identification area S to determine the actual left / right component information of the axle box spring 1. In the acquired image, one of the unidirectional connecting ear cavities 21 is used as a reference to define an identification area S1. When the outer sleeve 11 is placed in the molding die 2 in the left or right direction, at least one connecting ear 12 can appear in the identification area S1.

[0024] according to Figure 1It can be seen that after acquiring an image including the jacket 11 and the molding die 2, taking the predetermined left / right piece information as the left piece information as an example, if the jacket 11 is placed in a left piece manner, the connecting ear 12 on its upper part will normally appear in the rectangular identification area S1 in the figure. If the connecting ear 12 is visible in the identification area S1 in the image actually acquired, it indicates that the jacket 11 is placed correctly. Otherwise, if the actual jacket 11 is placed in a right piece manner, the connecting ear 12 will not appear in the identification area S1. It can be seen that the actual left / right piece information of the jacket 11 can be correctly judged according to whether the connecting ear 12 appears in the identification area S1. It should be noted that the demarcation shape of the identification area S1 is not limited, but it should be ensured that when the jacket 11 is placed in the molding die 2 in the left or right direction, at least one connecting ear 12 can appear in the identification area S1. As for how to judge whether the connecting ear 12 appears in the identification area S1, the specific implementation method can be adopted to adopt the ratio of the area where the connecting ear 12 appears to the area of ​​the identification area S1, or to adopt the standard image comparison method.

[0025] Embodiment 2: Figure 3 shown.

[0026] The difference from the first embodiment is that in the acquired image, an identification area S2 is delineated based on two opposite connecting ear cavities 21, and when the axle box spring 1 is placed in the molding mold 2 in the left or right direction, at least one connecting ear 12 may appear in the identification area S2.

[0027] This embodiment uses two diagonal connecting ear cavities 21 as a reference to define a rectangular identification area S2, which is similar to the judgment method of the first embodiment. Taking the left piece as an example, when the jacket 11 is placed in the left piece mode, the two connecting ears 12 will normally appear in the rectangular identification area S1 in the figure, otherwise it also indicates that the jacket 11 is placed incorrectly. It should be noted that the jacket 11 can only be placed in the molding mold 2 as a left / right piece, because the connecting ear cavities 21 and the connecting ears 12 have a matching relationship in position. If the jacket 11 is placed in other directions, the connecting ears 12 will not be able to be accommodated in the molding mold 2.

[0028] Embodiment 3: Figure 4 shown.

[0029] The geometric axis L1 of the bottom surface of the outer sleeve 11 is determined in the acquired image, and the geometric center line L2 of the connecting ear 12 of the bottom surface of the outer sleeve 11 is determined according to the position of the connecting ear 12 in the image, and the actual left / right part information of the axle box spring 1 is determined according to the position of the geometric center line L2 relative to the geometric axis L1. The geometric axis L1 is determined according to the contour information of the bottom surface of the outer sleeve 11 in the acquired image.

[0030] Different from the first and second embodiments, the judgment and analysis basis of this embodiment comes from the outer jacket 11 itself, and the connecting ear 12 is still used as the key identification information. When the outer jacket 11 is placed in the molding die 2, the direction of the geometric center line L2 of the connecting ear 12 can represent the actual direction information of the left and right parts of the outer jacket 11. Therefore, based on this, Figure 4 The middle jacket 11 is placed as a left piece, and the geometric center line L2 of its connecting ear 12 is on the left side relative to the geometric axis L1. If the predetermined left and right piece information is also a left piece, it means that the placement is correct. The basis for determining the geometric axis L1 of the bottom surface of the jacket 11 can be taken from the bottom surface contour of the jacket 11. After the image is corrected, the bottom surface contour of the jacket 11 will be an approximate circle, and its geometric axis L1 is not difficult to determine. Similarly, the geometric center line L2 of the connecting ear 12 can also be determined in a similar way using the contour of the connecting ear 12.

[0031] Embodiment 4: Figure 5 shown.

[0032] Different from the third embodiment, the geometric axis L1 is determined based on the image information of the molding die 2 in the acquired image. Since the cavity of the molding die 2 and the contour of the outer jacket 11 have a certain matching relationship, they can also be used to determine the geometric axis L1. A more simple and accurate determination can be made using the fixing bolts 5 outside the cavity in the molding die 2 image. Generally speaking, the geometric center line of the fixing bolts 5 outside the cavity is the central axis of the cavity of the molding die 2, and of course, it will also be the central axis of the outer jacket 11.

[0033] Embodiment 5, as Figure 6~Figure 8 shown.

[0034] A rail vehicle axle box spring similar parts detection device includes a base bracket 3, which can be connected to the top of the axle box spring forming device, and the base bracket 3 is connected to an X-direction telescopic mechanism, one end of the X-direction telescopic mechanism is connected to a first mounting plate 31, and the first mounting plate 31 is connected to an image acquisition unit 4. The X-direction telescopic mechanism is a telescopic cylinder in this embodiment, which can drive the image acquisition unit 4 to extend for image acquisition after obtaining an image acquisition instruction. The base bracket 3 carries the entire detection device, so that the detection device as a whole is easy to disassemble.

[0035] In a more preferred embodiment, the first mounting plate 31 is connected to the image acquisition unit 4 through a lifting mechanism, and the fill light unit 6 is connected to the bottom of the base bracket 3. The lifting mechanism can adjust the height of the image acquisition unit 4 relative to the surface of the molding die 2 to obtain a clearer image with a suitable size.

[0036] A protective cover 5 is hinged at the end of the base bracket 3. The protective cover 5 is an arc-shaped cover body and is located directly in front of the image acquisition unit 4. The protective cover 5 can be flipped to provide a certain degree of protection for the lens of the image acquisition unit 4 and prevent the lens of the image acquisition unit 4 from being dirty with oil and dust.

[0037] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0038] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preventing errors of similar parts of axle box springs of railway vehicles, characterized in that: The steps include: Step S1, obtaining product information of an axle box spring (1) to be formed, wherein the product information at least includes predetermined left / right piece information of the axle box spring (1); Step S2, placing the material of the iron piece including the outer sleeve (11) of the axle box spring (1) in the forming mold (2), and making the bottom surface of the outer sleeve (11) of the axle box spring (1) face upwards; Step S3, deploying an image acquisition device to acquire an image including the jacket (11) and the molding die (2); Step S4, processing and analyzing the image, and determining actual left / right piece information when the jacket (11) is placed in the molding die (2) based on the analysis result; Step S5, comparing the actual left / right component information of the outer sleeve (11) with the predetermined left / right component information of the axle box spring (1) obtained from the product information, and returning a correct material placement if they match, otherwise returning a placement error.

2. The method for preventing errors of similar parts of axle box springs of railway vehicles according to claim 1, characterized in that: In step S4, the acquired image is processed and analyzed, and the connecting ear (12) on the bottom surface of the outer sleeve (11) in the image is used as an identification mark of the actual left / right component information, and the actual left / right component information of the axle box spring (1) is judged and confirmed based on the identification mark.

3. The method for preventing similar parts of axle box springs of railway vehicles according to claim 2, characterized in that: An identification area S is determined in the acquired image, and it is judged whether the connecting ear (12) appears in the identification area S to determine the actual left / right part information of the axle box spring (1).

4. The method for preventing errors of similar parts of axle box springs of railway vehicles according to claim 3, characterized in that: In the acquired image, an identification area S1 is defined based on one of the unidirectional connection ear cavities (21). When the outer sleeve (11) is placed in the molding die (2) in a left or right direction, at least one connection ear (12) may appear in the identification area S1.

5. The method for preventing errors of similar parts of axle box springs of railway vehicles according to claim 3, characterized in that: In the acquired image, an identification area S2 is defined based on two opposing connection ear cavities (21), and when the axle box spring (1) is placed in the molding die (2) in a left or right direction, at least one connection ear (12) may appear in the identification area S2.

6. The method for preventing similar parts of axle box springs of railway vehicles according to claim 2, characterized in that: The geometric axis L1 of the bottom surface of the outer sleeve (11) is determined in the acquired image, and the geometric center line L2 of the connecting ear (12) on the bottom surface of the outer sleeve (11) is determined according to the position of the connecting ear (12) in the image. According to the position of the geometric center line L2 relative to the geometric axis L1, the actual left / right part information of the axle box spring (1) is determined.

7. The method for preventing similar parts of axle box springs of railway vehicles according to claim 6, characterized in that: The geometric axis L1 is determined based on the bottom surface contour of the jacket (11) in the acquired image or based on image information of the molding die (2) in the acquired image.

8. A railway vehicle axle box spring similar parts detection device, characterized in that: It comprises a base support (3) which can be connected to the top of the axle box spring forming device, the base support (3) is connected to an X-direction telescopic mechanism, one end of the X-direction telescopic mechanism is connected to a first mounting plate (31), and the first mounting plate (31) is connected to an image acquisition unit (4).

9. The railway vehicle axle box spring similar parts detection device according to claim 8, characterized in that: The first mounting plate (31) is connected to an image acquisition unit (4) via a lifting mechanism, and a fill light unit (6) is connected to the bottom of the base bracket (3).

10. The railway vehicle axle box spring similar parts detection device according to claim 9, characterized in that: A protective cover (5) is hingedly connected to the end of the base bracket (3); the protective cover (5) is an arc-shaped cover body and is located directly in front of the image acquisition unit (4).

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