Cable insulation wire core surface quality monitoring device and method

Abstract

The invention discloses a cable insulation wire core surface quality monitoring device and method, and relates to the technical field of cable detection. The cable insulation wire core surface quality monitoring device comprises a plurality of groups of monitoring units, the plurality of groups of monitoring units are arranged along the axial direction of a cable, and the plurality of groups of monitoring units are uniformly distributed in the circumferential direction of the cable; each monitoring unit is composed of a shading shell, a light source, a convex lens, an imaging plate, a first camera, a second camera, a first standard reference object, a second standard reference object and a defect reference object. According to the cable insulation wire core surface quality monitoring method, the cable insulation wire core surface quality monitoring device is designed and combined with the cable insulation wire core surface quality monitoring method, real-time surface quality detection can be carried out in the cable wire core production process, and diameter data and surface defect conditions in different directions are covered.

Description

Technical Field

[0001] This invention relates to the technical field of cable testing, and in particular to a device and method for monitoring the surface quality of cable insulation cores. Background Technology

[0002] The insulated conductor is the basic unit of a power cable, consisting of a conductor, an insulation layer, and inner and outer shielding layers. Currently, common power cable structures include three-core cables and single-core cables. Three-core cables contain three sets of insulated conductors, while single-core cables contain one set. The insulated conductor is the core conductive structure of the cable, and its structure and materials directly affect the cable's performance. During manufacturing and quality inspection, key parameters of the cable product need to be tested to confirm whether they meet standard requirements.

[0003] In recent years, guided by the "dual-carbon" strategy, the country has vigorously promoted the green and low-carbon development of the new power equipment industry. Currently, power cables mainly use cross-linked polyethylene (XLPE) insulation. The cross-linking and degassing processes are time-consuming and energy-intensive, and XLPE is a thermosetting material, making it difficult to recycle after decommissioning. Non-cross-linked cables use thermoplastic insulation materials, eliminating the need for cross-linking and degassing, offering advantages in energy conservation and environmental protection, and have become an important development direction for the cable industry. Based on domestic cable material research and the application needs of power grid units, several cable manufacturers have conducted trial production of non-cross-linked polypropylene (NPPP) cables, modifying existing XLPE cable production lines to produce NPP cables. However, due to significant differences between NPP and XLPE materials, and the unstable performance of polypropylene insulation and shielding materials from different modification routes and batches, fluctuations in cable insulation core dimensions and surface unevenness are common during current trial production. Therefore, it is necessary to strengthen parameter monitoring during the insulation core production process to ensure the quality of NPP insulated cable products.

[0004] Furthermore, for existing cross-linked polyethylene cables, the insulation core uses a three-layer co-extrusion process, and the insulation thickness is mainly controlled through X-ray inspection and cross-sectional sampling. Non-cross-linked polypropylene cables also use the three-layer co-extrusion process, but the screw structure, die extrusion temperature, and cooling method of the corresponding production line have changed. Currently, X-ray inspection and cross-sectional sampling can also be used for non-cross-linked polypropylene cables, but the following drawbacks still exist:

[0005] 1. Traditional sampling and slicing methods involve taking a sample from any end of the cable reel and measuring the insulation thickness using a projector to determine if the entire cable reel meets standards. However, this method only provides the insulation thickness at the sampling location and cannot fully represent the performance of the entire cable reel. When the insulation thickness fluctuates, it is prone to missed detections due to sampling location limitations. Furthermore, this method involves post-production testing; even if a non-compliant result is found, the product must be scrapped, and no corrective measures can be taken during production.

[0006] 2. X-ray inspection can be used in the production process. An X-ray transmitter and receiver are placed on either side of the cable at the extruder head. The X-ray beam emitted by the transmitter is perpendicular to the cable, and the receiver receives the signal. The thickness of the cable insulation layer is obtained by calculating the intensity of the X-ray beam on the receiver. However, X-rays pose certain risks to human health, and the equipment is expensive and bulky, limiting its installation and application. Furthermore, non-crosslinked polypropylene cables do not undergo a crosslinking process. After extrusion, they cool rapidly, resulting in a difference between the insulation thickness obtained at the extruder head and the final cooling thickness. Subsequent cooling processes, such as outer diameter fluctuations or eccentricity, make it difficult to obtain relevant information.

[0007] 3. Traditional sampling and slicing inspection and X-ray inspection methods cannot obtain information such as surface defects during the continuous production process of cables.

[0008] Due to the above-mentioned defects, there is currently no applicable method or device for monitoring the surface quality during the production process of insulated wire cores. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a device and method for monitoring the surface quality of cable insulation cores. This invention proposes a method for monitoring the surface quality of cable insulation cores during the production process of non-crosslinked polypropylene cable insulation cores based on visible light, and designs a corresponding monitoring device that can perform real-time surface quality detection during cable core production, covering diameter data in different directions and surface defect conditions.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] In a first aspect, the present invention provides a cable insulation core surface quality monitoring device, comprising several sets of monitoring units, wherein the several sets of monitoring units are arranged along the axial direction of the cable and the several sets of monitoring units are evenly distributed in the circumferential direction of the cable.

[0012] Each monitoring unit consists of a light-shielding shell, a light source, a convex lens, an imaging plate, a first camera, a second camera, a first standard reference, a second standard reference, and a defect reference.

[0013] The light source is located on the central axis inside the light-shielding shell. The convex lens is used to form a parallel light source inside the light-shielding shell, and the convex lens is located on the central axis of the light source. The imaging plate is used to acquire images of the cable, the first standard reference object, and the second standard reference object, and the imaging plate is located on the central axis of the convex lens. The convex lens is located between the light source and the cable, and the cable is located between the convex lens and the imaging plate.

[0014] The first camera and the second camera are used to capture images of the cable surface and the defect reference object, and the first camera and the second camera are located inside the light-shielding shell. The defect reference object is used to compare whether there are defects on the cable surface.

[0015] Preferably, the light-shielding shell includes a hollow shell body and two light-shielding edges. The internal space of the shell body is cylindrical. The shell body is provided with two circular holes for cables to pass through. The axial direction of the circular holes is perpendicular to the axial direction of the internal space of the shell body. The light-shielding edges are coaxially arranged with the cables, and the two light-shielding edges are arranged on the outer wall of the shell body and are coaxial with the two circular holes respectively.

[0016] Preferably, the diameter of the circular hole is larger than the outer diameter of the cable.

[0017] Preferably, the distance between the convex lens and the cable is greater than the distance between the light source and the convex lens, and the distance between the cable and the imaging plate is greater than the distance between the convex lens and the cable.

[0018] Preferably, the convex lens is circular, and the diameter of the convex lens is the same as the diameter of the internal space of the outer casing.

[0019] Preferably, the first camera and the second camera are positioned opposite each other, and both the first camera and the second camera are located between the convex lens and the cable, with the shooting directions of the first camera and the second camera being parallel to the radial direction of the cable.

[0020] Preferably, the first and second standard reference objects are cylinders with the same diameter, and the axes of the first and second standard reference objects are parallel to the axis of the cable. In the radial direction of the cable, the first standard reference object is located between the first camera and the cable, and the second standard reference object is located between the second camera and the cable. In the axial direction of the cable, the first standard reference object is located between the first camera and the imaging plate, and the second standard reference object is located between the cable and the imaging plate.

[0021] Preferably, the defect reference is located between the convex lens and the cable.

[0022] Secondly, the present invention also provides a method for monitoring the surface quality of cable insulation cores, comprising the following steps:

[0023] (1) Obtain the production speed V of the cable insulation core;

[0024] (2) The above-mentioned cable insulation core surface quality monitoring device is installed on the cable core movement path; the cable insulation core surface quality monitoring device includes four sets of monitoring units;

[0025] (3) Based on the imaging plate in the first monitoring unit, acquire images containing the cable and the first and second standard reference objects, and perform pixel analysis on the images to obtain the cable diameter R. 电缆1 Based on image analysis from the second, third, and fourth monitoring units, R was obtained sequentially. 电缆2 R 电缆 3. R 电缆4 ;

[0026] (4) Based on the images of the cable light source side in different directions obtained by the first camera and the second camera, pixel analysis is performed on the images to obtain the cable surface quality in that direction;

[0027] (5) The distance between the outer shells of two adjacent monitoring units along the cable axis is L; the time when passing through the first monitoring unit is t, and imaging photos in different directions are obtained in sequence according to the time interval Δt=L / V;

[0028] (6) Process the cable diameter data obtained from the four sets of imaging plates, then the cable diameter at the test position at time t is Rt = (R 电缆1 +R 电缆2 +R 电缆3 +R 电缆4 ) / 4, the cable outer diameter out-of-roundness is determined by the diameters in two mutually perpendicular directions (R) 电缆1 +R 电缆3 ) / 2 and (R 电缆2 +R 电缆4 The difference is obtained by taking the value of 1 / 2.

[0029] (7) Integrate the images from the four cameras to obtain the external quality data of the same cable core cross section.

[0030] Preferably, the cable diameter R is obtained in step (3). 电缆1 The specific steps are as follows:

[0031] Based on the image acquired by the imaging plate, define the range of horizontal coordinates X1 and X2, and vertical coordinates Y1, Y2, Y3, and Y4. Calculate the sum of pixel data within the range (X1~X2, Y1~Y2) to obtain S. 参照1 S is obtained by summing the pixel data within the range of (X1~X2, Y2~Y3). 电缆 Statistics (X) 1- S is obtained by summing the pixel data within the range of X2, Y3, and Y4. 参照2 Statistical analysis of the cable outer diameter R in this direction 电缆1 =R0×S 电缆 ×(S 参照2 / S 参照1 ).

[0032] It is important to note that monitoring is ongoing. The coordinate range is obtained by analyzing the images acquired each time. The horizontal coordinates X1 and X2 can be basically fixed in the first monitoring. After each image is acquired, the vertical coordinates Y1, Y2, Y3, and Y4 need to be reread in order to obtain the real-time outer diameter of the cable.

[0033] Preferably, the specific steps for obtaining the cable surface quality in step (4) are as follows:

[0034] Step 1: Based on the defect imaging of the visible light pattern identification reference object, obtain the pixel value matrix corresponding to different defects;

[0035] Step 2: Based on the X and Y coordinate ranges of different defects, obtain the coordinate difference ΔX = X along the X-axis. b -X a The minimum coordinate difference ΔY = Y along the Y-axis b -Y a ;

[0036] Step 3: Divide the area where the cable body is located into several small square areas according to △X and △Y, and obtain the pixel matrix of the corresponding small square area. Compare the difference of each pixel point in the adjacent pixel matrix in the X-axis direction one by one. If the number of different pixel values ​​exceeds a certain proportion, compare the corresponding data with the pixel value matrix corresponding to the defect. If the number of the same pixel values ​​exceeds a certain proportion, it is considered that there is a surface defect at that location.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] 1. This invention can perform real-time surface quality inspection during the production process of cable insulation cores, covering diameter data in different directions and surface defect conditions, and the data obtained is more comprehensive than that obtained by existing sampling and testing.

[0039] 2. This invention uses visible light-based technology, which is safer than the existing X-ray detection method. Furthermore, the characteristics of the cable insulation core itself will create images with strong black and white contrast, making it easier to implement technically.

[0040] 3. This invention, through its specially designed light-shielding shell and parallel light source, can avoid interference from external light during the testing process, resulting in more stable and reliable data obtained from the imaging images.

[0041] 4. This invention uses diameter data obtained from four different directions to calculate diameter data in two mutually perpendicular directions, and analyzes out-of-roundness through difference analysis, resulting in more comprehensive data.

[0042] 5. In diameter monitoring based on images obtained from an imaging plate, this invention uses two standard reference objects at different locations for calculation, avoiding data errors caused by test positions under non-ideal parallel light source conditions.

[0043] 6. This invention proposes a pixel analysis method based on visible light imaging to achieve quantitative analysis of cable diameter and cable surface quality, and can perform automatic calculations. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the monitoring unit of the present invention along the radial direction of the cable.

[0045] Figure 2 This is a schematic diagram of the monitoring unit of the present invention along the radial direction of the cable.

[0046] Figure 3 This is an image analysis diagram of the imaging plate described in this invention.

[0047] Figure 4 This is the camera image analysis diagram described in this invention.

[0048] Figures 1-2 In the middle: 1 is the light-shielding shell; 2 is the light source; 3 is the convex lens; 4 is the imaging plate; 5 is the first camera; 6 is the second camera; 7 is the first standard reference object; 8 is the second standard reference object; 9 is the defect reference object; 10 is the light-shielding edge; 11 is the cable. Detailed Implementation

[0049] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments, but the scope of protection and implementation of the present invention are not limited thereto.

[0050] Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0051] Example 1

[0052] This embodiment discloses a cable insulation core surface quality monitoring device, including four monitoring units. The four monitoring units are arranged along the axial direction of the cable, and the outer shells of the four monitoring units are 90° to each other in the circumferential direction of the cable.

[0053] like Figures 1-2 As shown, each monitoring unit includes a light-shielding shell 1, a light source 2, a convex lens 3, an imaging plate 4, a first camera 5, a second camera 6, a first standard reference object 7, a second standard reference object 8, and a defect reference object 9; the light-shielding shell 1 includes a hollow shell body and two light-shielding edges 10.

[0054] like Figure 2As shown, the internal space of the outer casing is cylindrical. The outer casing has two circular holes through which the cable 11 passes. The axis of the circular holes is perpendicular to the axis of the internal space of the outer casing. The diameter of the circular holes is larger than the outer diameter of the cable, allowing the cable core to continuously pass through the holes during production. The axis of the cable 11 is perpendicular to the axis of the internal space of the outer casing.

[0055] like Figure 2 As shown, the light-shielding edge 10 is circular and coaxially arranged with the cable 11. The two light-shielding edges 10 are arranged on the outer wall of the housing body and coaxial with the two circular holes respectively. The light-shielding edge 10 has a certain length along the axial direction of the cable, which can ensure that a dark room is formed inside the light-shielding housing 1.

[0056] like Figure 2 As shown, the convex lens 3 is circular and located between the light source 2 and the cable 11. The diameter of the convex lens 3 is equal to the diameter of the internal space of the outer casing. Adjusting the distance between the convex lens 3 and the light source 2 ensures that the light source is located at the focal point of the convex lens, forming a parallel light source inside the device. The cable 11 is located between the convex lens 3 and the imaging plate 4.

[0057] like Figure 2 As shown, the light source 2, the convex lens 3, and the imaging plate 4 are all located on the central axis of the internal space of the housing body; the distance between the convex lens 3 and the cable 11 is greater than the distance between the light source 2 and the convex lens 3, and the distance between the cable 11 and the imaging plate 4 is greater than the distance between the convex lens 3 and the cable 11. When the light source is turned on, an image with the same diameter as the cable can be formed on the imaging plate, thus obtaining the outer diameter of the cable in that direction.

[0058] like Figure 1 As shown, the first camera 5 and the second camera 6 are used to photograph the surface of the cable 11, and the first camera 5 and the second camera 6 are located on the inner wall of the light-shielding housing. The shooting directions of the first camera 5 and the second camera 6 are opposite to each other, and both the first camera 5 and the second camera 6 are located between the convex lens 3 and the cable 11. The shooting directions of the first camera 5 and the second camera 6 are parallel to the radial direction of the cable. The cable 11 is positioned in the shooting directions of the first camera 5 and the second camera 6, ensuring that the first camera and the second camera capture at least one-quarter of the circumference of the cable surface. By using the configuration of the first camera and the second camera, visible light images of the cable from different directions can be obtained.

[0059] Both the first standard reference object 7 and the second standard reference object 8 are standard cylinders with known external dimensions and a diameter of R0, such as... Figure 1As shown, the axes of the first reference object 7 and the second reference object 8 are both parallel to the axis of the cable 11. In the radial direction of the cable, the first reference object 7 is located between the first camera 5 and the cable 11, and the second reference object 8 is located between the second camera 6 and the cable 11. In the axial direction of the cable, the first reference object 7 is located between the first camera 5 and the imaging plate 4, and the second reference object 8 is located between the cable 11 and the imaging plate 4.

[0060] The defect reference object 9 is located as follows: Figure 1 As shown, the defect reference object is located directly above cable 11, and its surface material is the same as that of the cable. The defect reference object is a cylinder with defects such as protrusions and scratches on its surface. The defect reference object is used to compare whether there are defects on the cable surface.

[0061] This embodiment also discloses a method for monitoring the surface quality of cable insulation cores, including the following steps:

[0062] (1) Start the production of cable insulation cores and obtain the production speed V of polypropylene cable insulation cores.

[0063] (2) Install a visible light-based cable insulation core surface quality monitoring device on the cable core movement path.

[0064] (3) Based on the imaging plate in the first monitoring unit, images containing the cable and the first and second standard reference objects can be acquired. Pixel analysis of the images can then be performed to obtain the cable diameter R in that direction. 电缆 1. Based on the image analysis of the second, third, and fourth monitoring units, R is obtained sequentially. 电缆2 R 电缆3 R 电缆4 Each pixel t corresponds to a unique coordinate (X) in the horizontal and vertical directions. t Y t If the pixel is black, assign it a value of 1; if it is white, assign it a value of 0.

[0065] like Figure 3 As shown, based on the image acquired by the imaging plate, the ranges of horizontal coordinates X1 and X2, and vertical coordinates Y1, Y2, Y3, and Y4 are defined. The sum of pixel data within the range (X1-X2, Y1~Y2) is used to obtain S. 参照1 S is obtained by summing the pixel data within the range of (X1~X2, Y2~Y3). 电缆 S is obtained by summing the pixel data within the range of (X1~X2, Y3~Y4). 参照2 Statistical analysis of the cable outer diameter R in this direction 电缆1 =R0×S 电缆 ×(S 参照2 / S 参照1 ).

[0066] (4) Based on the images of the cable light source side acquired by the first and second cameras in different directions, pixel analysis of the images can be performed to obtain the cable surface quality in that direction, such as... Figure 4 As shown, each pixel t corresponds to a unique coordinate (X) in the horizontal and vertical directions. t Y t If the pixel is black, assign it a value of 1; if it is white, assign it a value of 0.

[0067] Step 1: Based on the defect imaging of the visible light pattern identification reference object, obtain the pixel value matrix corresponding to different defects;

[0068] Step 2: Based on the X and Y coordinate ranges of different defects, obtain the coordinate difference ΔX = X along the X-axis. b -X a The minimum coordinate difference ΔY = Y along the Y-axis b -Y a ;

[0069] Step 3: Divide the area where the cable body is located into several small square areas according to △X and △Y, and obtain the pixel matrix of the corresponding small square area. Compare the difference of each pixel point in the adjacent pixel matrix in the X-axis direction one by one. If the number of different pixel values ​​exceeds a certain proportion (such as 5%), then compare the corresponding data with the pixel value matrix corresponding to the defect. If the number of the same pixel values ​​exceeds a certain proportion (such as 80%), then it is considered that there is a surface defect at that location.

[0070] (5) The distance between the outer shells of two adjacent monitoring units along the cable axis is L. The time taken to pass through the first monitoring unit is t. Imaging images in different directions are obtained sequentially according to the time interval Δt = L / V.

[0071] (6) Process the cable diameter data obtained from the four sets of imaging plates, then the cable diameter at the test position at time t is Rt = (R 电缆1 +R 电缆2 +R 电缆3 +R 电缆4 ) / 4, the cable outer diameter out-of-roundness can be determined by the diameters (R) in two mutually perpendicular directions. 电缆1 +R 电缆3 ) / 2 and (R 电缆2 +R 电缆4 The difference is obtained by taking the value of ) / 2.

[0072] (7) By integrating the images from the four cameras, external quality data on the same cable core cross-section can be obtained.

[0073] This invention is applicable to the design of surface quality monitoring devices in the production process of cable insulation cores, including but not limited to light-shielding shells, parallel light source designs, and full coverage of data from different directions based on multiple monitoring units.

[0074] The cable insulation core diameter measurement method based on imaging plate images uses parallel light sources to form standard reference objects and images of the cable under test at different positions. The cable diameter is obtained by pixel assignment. The corresponding algorithm effectively eliminates errors and avoids interference from external light in the testing process. The data obtained based on the imaging images is more stable and reliable.

[0075] The present invention is a method for analyzing surface defects of cable insulation core based on camera images. It uses images of the defect reference object and the cable under test to be captured from different angles, and obtains the pixel matrix corresponding to the defect block through pixel assignment, forming a comparative analysis process of adjacent pixel matrix and defect pixel matrix.

[0076] This invention combines the production speed of cable insulation cores with the interval settings of four monitoring units to set the start time and sequential image acquisition intervals, thereby integrating the diameter and surface quality of the same cable insulation core cross-section in different directions.

[0077] In summary, this invention enables real-time surface quality inspection during cable core production, covering diameter data in different directions and surface defects, providing more comprehensive data compared to existing sampling and inspection methods.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A device for monitoring the surface quality of cable insulation cores, characterized in that, It includes several sets of monitoring units, which are arranged along the axial direction of the cable and are evenly distributed in the circumferential direction of the cable. Each monitoring unit consists of a light-shielding shell, a light source, a convex lens, an imaging plate, a first camera, a second camera, a first standard reference, a second standard reference, and a defect reference. The light source is located on the central axis inside the light-shielding shell. The convex lens is used to form a parallel light source inside the light-shielding shell, and the convex lens is located on the central axis of the light source. The imaging plate is used to acquire images of the cable, the first standard reference object, and the second standard reference object, and the imaging plate is located on the central axis of the convex lens. The convex lens is located between the light source and the cable, and the cable is located between the convex lens and the imaging plate. The first camera and the second camera are used to capture images of the cable surface and the defect reference object, and the first camera and the second camera are located inside the light-shielding shell. The defect reference object is used to compare whether there are defects on the cable surface.

2. The cable insulation core surface quality monitoring device as described in claim 1, characterized in that, The light-shielding shell includes a hollow shell body and two light-shielding edges. The internal space of the shell body is cylindrical. The shell body is provided with two circular holes for cables to pass through. The axis of the circular holes is perpendicular to the axis of the internal space of the shell body. The light-shielding edges are coaxially arranged with the cables, and the two light-shielding edges are arranged on the outer wall of the shell body and are coaxial with the two circular holes respectively.

3. The cable insulation core surface quality monitoring device as described in claim 2, characterized in that, The diameter of the circular hole is larger than the outer diameter of the cable.

4. The cable insulation core surface quality monitoring device as described in claim 2, characterized in that, The distance between the convex lens and the cable is greater than the distance between the light source and the convex lens, and the distance between the cable and the imaging plate is greater than the distance between the convex lens and the cable.

5. The cable insulation core surface quality monitoring device as described in claim 2, characterized in that, The diameter of the convex lens is the same as the diameter of the internal space of the outer shell.

6. The cable insulation core surface quality monitoring device as described in claim 1, characterized in that, The first camera and the second camera are positioned opposite each other, and both the first camera and the second camera are located between the convex lens and the cable. The shooting directions of the first camera and the second camera are parallel to the radial direction of the cable.

7. The cable insulation core surface quality monitoring device as described in claim 2, characterized in that, The first and second standard reference objects are cylinders with the same diameter, and the axes of the first and second standard reference objects are parallel to the axis of the cable. In the radial direction of the cable, the first standard reference object is located between the first camera and the cable, and the second standard reference object is located between the second camera and the cable. Along the cable axis, the first standard reference is located between the first camera and the imaging plate, and the second standard reference is located between the cable and the imaging plate. And / or, the defect reference is located between the convex lens and the cable.

8. A method for monitoring the surface quality of cable insulation cores, characterized in that, Includes the following steps: (1) Obtain the production speed V of the cable insulation core; (2) A cable insulation core surface quality monitoring device as described in any one of claims 1-7 is installed on the cable core movement path; the cable insulation core surface quality monitoring device includes four sets of monitoring units; (3) Based on the imaging plate in the first monitoring unit, acquire an image containing the cable and the first and second standard reference objects, perform pixel analysis on the image, and obtain the cable diameter R. 电缆1 ; Based on image analysis from the second, third, and fourth monitoring units, R was obtained sequentially. 电缆2 R 电缆 3. R 电缆4 ; (4) Based on the images of the cable light source side in different directions obtained by the first camera and the second camera, pixel analysis is performed on the images to obtain the cable surface quality in that direction; (5) The distance between the outer shells of two adjacent monitoring units along the cable axis is L; the time when passing through the first monitoring unit is t, and imaging photos in different directions are obtained in sequence according to the time interval Δt=L / V; (6) Process the cable diameter data obtained from the four sets of imaging plates, and then the cable diameter at the test position at time t is R. t =(R 电缆1 +R 电缆2 +R 电缆3 +R 电缆4 ) / 4, the cable outer diameter out-of-roundness is determined by the diameters in two mutually perpendicular directions (R) 电缆1 +R 电缆3 ) / 2 and (R 电缆2 +R 电缆4 The difference is obtained by taking the value of 1 / 2. (7) Integrate the images from the four cameras to obtain the external quality data of the same cable core cross section.

9. The method for monitoring the surface quality of cable insulation cores as described in claim 8, characterized in that, In step (3), the cable diameter R is obtained. 电缆1 The specific steps are as follows: Based on the image acquired by the imaging plate, define the range of horizontal coordinates X1 and X2, and vertical coordinates Y1, Y2, Y3, and Y4. Calculate the sum of pixel data within the range (X1~X2, Y1~Y2) to obtain S. 参照1 S is obtained by summing the pixel data within the range of (X1~X2, Y2~Y3). 电缆 S is obtained by summing the pixel data within the range of (X1~X2, Y3~Y4). 参照2 Statistical analysis of the cable outer diameter R in this direction 电缆1 =R0×S 电缆 ×(S 参照2 / S 参照1 R0 is the diameter of the first or second reference object.

10. The method for monitoring the surface quality of cable insulation cores as described in claim 8, characterized in that, The specific steps for obtaining the cable surface quality in step (4) are as follows: Step 1: Based on the defect imaging of the visible light pattern identification reference object, obtain the pixel value matrix corresponding to different defects; Step 2: Based on the X and Y coordinate ranges of different defects, obtain the coordinate difference ΔX = X along the X-axis. b -X a The minimum coordinate difference ΔY = Y along the Y-axis b -Y a ; Step 3: Divide the area where the cable body is located into several small square areas according to △X and △Y, and obtain the pixel matrix of the corresponding small square area. Compare the difference of each pixel point in the adjacent pixel matrix in the X-axis direction one by one. If the number of different pixel values ​​exceeds a certain proportion, compare the corresponding data with the pixel value matrix corresponding to the defect. If the number of the same pixel values ​​exceeds a certain proportion, it is considered that there is a surface defect at that location.

Images