A power cable production deviation measurement system and deviation measurement method

Abstract

The present invention discloses a power cable production deviation measurement system, comprising a deflection device installed on the output side of a multi-layer co-extruder and rotatable along the cable pulling and moving direction, a cable transmission conduit interconnected with the deflection device, and a detection and processing part communicatively connected to the deflection device. The deflection device comprises a support frame, a positioning sleeve shaft, a deflection scanning housing, and a light detector. The present invention also discloses a deflection measurement method thereof, wherein light detectors are arranged at an angle of 120° along the cable pulling direction, and a laser distance sensor is used to detect the radial edge distance between the cable and the positioning sleeve shaft; first, a light irradiation head simultaneously emits light perpendicularly to the cable at different azimuth positions to obtain shadow image data generated at different positions, and then three light irradiation heads emit light perpendicularly to obtain shadow image data generated at the same position. The present invention can perform multiple detections on various positions of the cable, effectively solving the problem of eccentricity quality detection when the cable is subjected to multi-layer co-extrusion.

Description

Technical Field

[0001] The present invention belongs to the technical field of cable production, and in particular relates to a deviation measurement system and a deviation measurement method for power cable production. Background Art

[0002] Power cables generally refer to wires made of one or more mutually insulated conductors covered by an insulating protective layer, used to transmit electricity or information from one location to another. my country's power industry is currently developing rapidly, and cables play a vital role in power transmission and industrial information communications. Therefore, cable production quality issues are of great concern to the power industry. Cable eccentricity is a common problem faced by manufacturers. Due to the manufacturing process, the multi-layer co-extrusion of the insulation of medium- and high-voltage cross-linked polyethylene insulated power cables can cause the conductive core and insulation layer to be non-concentric. This results in varying insulation thickness across the cable cross-section, increasing the eccentricity of the insulation core. When the insulation thickness is uneven and eccentric, the electric field distribution within the cable insulation is also uneven. This abnormal electric field is concentrated in areas where the insulation layer is thinner, increasing the electric field strength there. Insulation eccentricity deteriorates the radial electric field structure, causing insulation breakdown or burnout. This poses a safety hazard to the cable and degrades its transmission performance, significantly impacting the entire power system. Therefore, when the cable is co-extruded, the eccentricity of the cable input needs to be detected. Traditionally, the eccentricity of the cable is mainly measured by random sampling, and is detected by manual visual inspection, estimated measurement between vernier calipers, and cross-sectional slicing. These traditional detection methods generally have large measurement errors and are inconvenient to operate. The production process cannot timely monitor and measure the eccentricity and thickness of each layer of the cable. Once the test fails, the entire batch of cables will be scrapped, resulting in material waste and huge economic losses. Therefore, a timely, fast and practical cable deflection measuring device has important economic and social production benefits for cable production. Summary of the Invention

[0003] The present invention aims to provide a power cable production deviation measurement system and method. The system can detect the eccentricity of cables during co-extrusion production in real time and perform multiple tests on each position of the cable. The entire process is fully automated, effectively solving the problem of eccentricity quality detection of cable insulation and core conductors during multi-layer co-extrusion. To achieve the above objectives, the present invention employs the following technical effects:

[0004] According to one aspect of the present invention, a power cable production deviation measurement system is provided, comprising a deviation measurement device installed on the output side of a multi-layer co-extruder and rotatable along the cable pulling movement direction, a cable transmission conduit interconnected with the deviation measurement device, and a detection and processing part communicatively connected to the deviation measurement device, the deviation measurement device comprising a support frame, a positioning sleeve shaft, a deviation measurement scanning shell and a light detector, the two ends of the positioning sleeve shaft are rotatably arranged on the support frame through bearing seats, three deviation measurement scanning shells connected at an angle of 120° are arranged on the outer wall of the positioning sleeve shaft and extended along the cable pulling direction, a light detector is arranged in each deviation measurement scanning shell, the light detectors in each deviation measurement scanning shell are not on the same vertical plane with each other, and are respectively distributed around the positioning sleeve shaft along the cable pulling direction, the laser detectors in adjacent deviation measurement scanning shells are spatially distributed at an angle of 120°, and the light detectors are connected to the detection and processing part.

[0005] The above scheme is further preferred, that the detection and processing part at least includes a central controller, a communication module, a laser ranging sensor and a host computer, the central controller is communicatively connected to the host computer through the communication module, the light detector includes a light irradiation part and a light receiving part, the light irradiation part is composed of a power module and a light irradiation head, the power module is electrically connected to the light irradiation head, a sealed cavity sliding along the inner wall is provided in the deflection scanning housing, the power module is provided at the external top end of the sealed cavity, the light irradiation head of the light irradiation part is provided in the sealed cavity, the light receiving part is provided in front of the light irradiation head and at the bottom of the sealed cavity perpendicular to the other side of the cable, the laser ranging sensors are symmetrically provided radially above and below the input side of the positioning sleeve shaft, and the laser ranging sensor and the light receiving part are connected to the central controller.

[0006] The above scheme is further preferred, in which a fixed sleeve is coaxially arranged in front of the axial direction of the input side of the positioning sleeve shaft, the laser ranging sensor is arranged in the radial direction between the output side of the fixed sleeve and the input side of the positioning sleeve shaft, and an irradiation window for irradiation or scanning by the light irradiation head is provided on the outer wall of the positioning sleeve shaft and along the cable pulling movement direction.

[0007] The above scheme is further preferred, in which a push rod motor is arranged in the deflection measurement scanning housing and directly in front of the top outer wall of the sealed cavity, the output shaft of the push rod motor is transmission-connected to the top outer wall of the sealed cavity, the fixed end of the push rod motor is arranged on the top inner wall of the deflection measurement scanning housing, and the control end of the push rod motor is electrically connected to the central controller.

[0008] The above solution is further preferred in that a cooling cavity that is interconnected is provided inside the top wall and the side walls of the sealed cavity, and the cooling cavity is filled with a coolant.

[0009] The above solution is further preferred in that the light irradiation head is a visible light irradiation head which uses an infrared irradiation lamp, and the light receiving part is a visible light receiving head which uses an infrared CCD image sensor.

[0010] The above solution is further preferred, wherein the light irradiation head is an X-ray emitting head, which uses an X-ray irradiation tube, and the light receiving part is an X-ray receiving head, which uses an X-ray photoelectric sensor.

[0011] The above solution is further preferred, wherein a rotating ring is sleeved on the outer wall of the output side of the positioning sleeve shaft, the output end of the positioning sleeve shaft is connected to the cable transmission conduit via the rotating ring, a gear is provided on the outer wall of the positioning sleeve shaft near the rotating ring, an angle sensor for detecting the rotation angle of the gear is provided on the gear, and the angle sensor is electrically connected to the detection processing part;

[0012] According to another aspect of the present invention, the present invention utilizes a deviation measurement method of a power cable production deviation measurement system, comprising the following steps:

[0013] Step 1: Light detectors are distributed on the outer wall of the positioning sleeve shaft and inside the deflection scanning housing at an angle of 120° along the cable pulling direction. Each light detector is distributed on the periphery of the cable from the input side to the output side of the positioning sleeve shaft. Each light detector is perpendicular to the cable, and adjacent light detectors form a 120° angle in space.

[0014] Step 2: The three-layer co-extruded cable is conveyed into the positioning sleeve shaft, and then sequentially fed into the cable conveying conduit for traction and conveying. On the input side of the positioning sleeve shaft, a laser distance measuring sensor is used to detect whether the upper and lower outer walls of the cable are at the same distance from the radial edge of the positioning sleeve shaft, so that the cables are respectively located at the center of the positioning sleeve shaft;

[0015] Step 3: In each deflection measurement scanning housing, the push rod motor is started respectively to push the sealed cavity to slide in each deflection measurement scanning housing, and the vertical distance between the light irradiation head and the cable is adjusted. During each interval of the laser ranging sensor detecting the radial edge distance, the light irradiation heads in the three deflection measurement scanning housings first emit vertical irradiation light to the cable at different azimuth positions at the same time, forming a shadow on the back of the cable, and the shadow image data generated when the three light irradiation heads simultaneously and vertically irradiate different positions of the cable are obtained through the light receiving parts respectively; then the light irradiation heads in the three deflection measurement scanning housings are started in sequence from the input side to the output side of the positioning sleeve shaft. During the cable traction and transmission process, each light irradiation head emits irradiation light to the same position of the cable in sequence and at different azimuths at a specified time interval, and also forms a shadow on the back of the cable. The light receiving part at each position obtains the shadow image data generated when the cable irradiates the same position at different times during the traction process;

[0016] Step 4: The light receiving part transmits the shadow image data S1 generated at different positions to the central controller for processing, and then uploads the processed shadow image data S1 generated at different positions to the host computer to calculate the width of the shadow image data S1 generated at different positions of the cable, and then calculates the first eccentricity of the cable according to the width of the shadow image data S1 generated at different positions and displays the calculation results; and each of the light receiving parts 242 transmits the shadow image data S2 generated at the same position to the central controller for processing, and then uploads the processed shadow image data S2 generated at the same position to the host computer to calculate the width of the shadow image data S2 of the cable obtained by each light receiving part, and then calculates the first eccentricity of the cable according to the width of the shadow image data S2 generated at the same position and displays the calculation results;

[0017] Step 5: The positioning sleeve shaft is driven to rotate relative to the cable transmission conduit by an angle through the driving gear, and the deflection scanning housing and the optical detector are driven to rotate at a predetermined angle at the same time. Then the above steps are repeated to detect the eccentricity of the cable.

[0018] The above solution is further preferred, wherein in step 4, calculating the first eccentricity of the cable according to the width of the shadow image data generated at the same position comprises the following steps:

[0019] Step 41, the central controller obtains the time interval of the laser ranging sensor detecting the cable;

[0020] Step 42, the central controller obtains, through the three light receiving parts, shadow images when the corresponding light irradiation head irradiates the same position of the cable at different times within the time interval;

[0021] Step 43, respectively extracting the shadow image width of the cable insulation layer and the shadow image width of the cable core conductor obtained at the same position and at the same time of each light receiving part;

[0022] Step 44, performing difference calculations on the shadow image width of the insulation layer and the shadow image width of the cable core conductor with corresponding set thresholds, to obtain a difference sequence width of the insulation layer and a difference sequence width of the cable core conductor for the shadow image widths at the same position and time;

[0023] Step 45, sorting the insulation layer difference sequence width and the cable core conductor difference sequence width, extracting the maximum value, minimum value and average value of the insulation layer difference sequence width, and calculating the eccentricity of the insulation layer based on the maximum value, minimum value and average value of the insulation layer difference sequence width, and calculating the eccentricity of the cable core conductor based on the maximum value and minimum value of the cable core conductor difference sequence width.

[0024] In summary, since the present invention adopts the above technical solution, the present invention has the following technical effects:

[0025] The cable production deviation measurement and detection system of the present invention can detect the eccentricity of the cable during co-extrusion production in real time, and perform multiple detections on various directions of the cable. The entire process is fully automated and easy to operate. It can effectively solve the eccentricity quality detection problem of the cable insulator and cable core conductor when the cable is multi-layer co-extruded, thereby improving production efficiency. It has high accuracy and low interference, and is easy to promote and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the installation of a power cable production deviation measurement system of the present invention;

[0027] Figure 2 1 is a schematic diagram of the installation structure of the deflection measuring device of the present invention;

[0028] Figure 3 This is a schematic diagram of the external structure of the deflection measurement scanning housing of the present invention;

[0029] Figure 4 It is a schematic diagram of the detection and processing part of the present invention;

[0030] Figure 5 This is a schematic diagram of the external structure of the positioning sleeve shaft of the present invention;

[0031] Figure 6 This is a schematic diagram of the internal structure of the deflection measurement scanning housing of the present invention;

[0032] Figure 7 It is a structural schematic diagram of the sealed cavity of the present invention;

[0033] Figure 8It is a schematic diagram of the deviation detection and calculation of the deviation detection device of the present invention;

[0034] Figure 9 This is a flow chart of a power cable production deviation measurement according to the present invention;

[0035] In the accompanying drawings, there are a multi-layer co-extruder 1, a deflection measuring device 2, a cable transmission conduit 3, a cable 10, a detection and processing part 11, a support frame 20, a positioning sleeve shaft 21, a deflection measuring scanning housing 22, a light detector 24, a wire outlet hole 25, a scattered hole 26, a central controller 110, a communication module 111, a laser ranging sensor 112, a host computer 113, a rotating ring 211, a gear 212, a power module 240, a light irradiation head 241, a light receiving part 242, a sealing cavity 243, a push rod motor 244, a cooling cavity 245, and liquid nitrogen 246. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and by way of preferred embodiments. However, it should be noted that many of the details listed in this specification are merely provided to help the reader gain a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be practiced even without these specific details.

[0037] like Figure 1 、 Figure 2 and Figure 3 As shown, according to one aspect of the present invention, a power cable production deviation measurement system is provided, comprising a deviation measurement device 2 installed on the output side of a multi-layer co-extruder 1 and rotatably arranged along the pulling and moving direction of the cable 10, a cable transmission conduit 3 interconnected with the deviation measurement device 2, and a detection processing part 11 communicatively connected to the deviation measurement device 2, the deviation measurement device 2 comprising a support frame 20, a positioning sleeve shaft 21, a deviation measurement scanning housing 22 and a light detector 24, the two ends of the positioning sleeve shaft 21 are rotatably arranged on the support frame 20 through bearing seats 23 respectively. Three deflection measurement scanning shells 22 are arranged on the outer wall of the positioning sleeve shaft 21 and extended along the pulling direction of the cable 10, and are connected at an angle of 120°. A light detector 24 is arranged in each deflection measurement scanning shell 22. The light detectors 24 in each deflection measurement scanning shell 22 are not on the same vertical plane with each other, and are distributed around the positioning sleeve shaft 21 along the pulling direction of the cable 10. The laser detectors 24 in adjacent deflection measurement scanning shells 22 are distributed at an angle of 120° in space, and the light detectors 24 are connected to the detection processing part 11.

[0038] In the present invention, Figure 1 、 Figure 2 and Figure 4As shown, the detection processing part 11 at least includes a central controller 110, a communication module 111, a laser ranging sensor 112 and a host computer 113. The central controller 110 adopts an ARM controller or a DSP processor. The central controller 110 is connected to the host computer through the communication module. The communication module is a wireless communication module or a serial communication module. The light detector 24 includes a light irradiation part and a light receiving part 242. The light irradiation part is composed of a power module 240 and a light irradiation head 241. The power module 240 is electrically connected to the light irradiation head 241. A sealed cavity 243 sliding along the inner wall is provided in the deflection scanning housing 22. The power module 240 is provided at the outer top of the sealed cavity 242. The power module 240 provides power to the light irradiation head 241. The light detector 24 includes a light irradiation part and a light receiving part 242. The light irradiation head 241 of the irradiation part, the light receiving part 242 is arranged in front of the light irradiation head 241 and at the bottom of the sealed cavity 243, vertically relative to the other side of the cable 10, and the laser ranging sensor 112 is symmetrically arranged radially above and below the input side of the positioning sleeve shaft 21, respectively. The laser ranging sensor 112 and the light receiving part 242 are connected to the central controller 110; the central controller 110 communicates with the host computer 113, and the central controller 110 obtains and processes the image data of the cable irradiated by the light receiving part 242, and uploads the obtained image data to the communication of the host computer. The host computer 113 is used to send detection commands, data processing and display and record detection results. After the host computer 113 processes the data uploaded by the central controller 110, it sends a detection command to the central controller 110 again.

[0039] In the present invention, Figure 1As shown, a fixed sleeve 4 is coaxially arranged in front of the axial direction of the input side of the positioning sleeve shaft 21, and the laser ranging sensor 112 is arranged in the radial direction between the output side of the fixed sleeve and the input side of the positioning sleeve shaft 21. The laser ranging sensor 112 is used to detect the radial edge distance between the upper and lower outer walls of the cable 10 and the positioning sleeve shaft 21 on the input side of the positioning sleeve shaft 21. If the radial edge distance between the two side edges of the cable 10 and the positioning sleeve shaft 21 exceeds the preset specified distance, a reminder message will be sent to the production personnel to adjust the position of the cable 10 to ensure that the cable 10 is in the correct position. The center of the positioning sleeve shaft 21 is arranged so that the irradiation light emitted by the light irradiation head 241 can completely illuminate the front center of the cable 10 and form a symmetrical shadow on the back of the cable 10; an irradiation window 210 for irradiation or scanning by the light irradiation head 241 is provided on the outer wall of the positioning sleeve shaft 21 and along the pulling and moving direction of the cable 11. The light emitted by the light irradiation head 241 passes through the bottom of the sealed cavity 243, and then passes through the irradiation window 210 to irradiate the front of the cable 10 and form a shadow on the back of the cable. By measuring the width of the shadow, the eccentricity of the cable can be calculated based on the width of the shadow.

[0040] In the present invention, combined with Figure 4 and Figure 6 A push rod motor 244 is provided in the deflection measurement scanning housing 22 and directly in front of the top outer wall of the sealed cavity 243. The output shaft of the push rod motor 244 is transmission-connected to the top outer wall of the sealed cavity 243. The fixed end of the push rod motor 244 is provided on the top inner wall of the deflection measurement scanning housing 22. The control end of the push rod motor 244 is electrically connected to the central controller 110. The push rod motor 244 pushes the sealed cavity 243 to slide in the deflection measurement scanning housing 22, thereby adjusting the effective distance between the light irradiation head 24 installed in the sealed cavity 243 and the cable 10, adapting to the detection of cables of different diameters, and better irradiating and detecting the eccentricity of the cable 10. At the same time, it improves the steam, smoke or heat generated by the cable insulation material during three-layer co-extrusion to affect the irradiation light transmission of the light irradiation head 241, prevents the light transmission dispersion from affecting the irradiation scanning of the light irradiation head 241, and can adjust the distance between the light irradiation head and the cable, thereby improving the irradiation scanning effect of the light irradiation head 241.

[0041] In the present invention, combined with Figure 4 、 Figure 6 and Figure 7A cooling cavity 245 that is interconnected is provided inside the top wall and side wall of the sealed cavity 243, and liquid nitrogen 246 is provided in the cooling cavity. The coolant is liquid nitrogen or cooling oil, so as to ensure that the heat generated by the light irradiation head 241 during irradiation can be cooled by the liquid nitrogen, so as to improve the accuracy of light irradiation detection. A wire outlet hole 24 is provided on the side wall of each deflection measurement scanning housing 22, and the data line and other control wires of the light irradiation head 241 are led out through the wire outlet hole 24 and connected to the detection processing part 11. A diffusion hole 26 is provided on the side wall of the deflection measurement scanning housing 22 opposite to the wire outlet hole 24, and the heat generated by the light irradiation head 241 during irradiation is discharged from the diffusion hole 26.

[0042] In the present invention, Figure 2 and Figure 5 As shown, a rotating ring 211 is sleeved on the outer wall of the output side of the positioning sleeve shaft 21, and the output end of the positioning sleeve shaft 21 is connected to the cable transmission conduit 3 through the rotating ring 211. A gear 212 is provided on the outer wall of the positioning sleeve shaft 21 close to the rotating ring 211. An angle sensor (not shown) for detecting the rotation angle of the gear is provided on the gear 212. The angle sensor is electrically connected to the detection processing part 11, and the angle sensor transmits the detected angle information to the detection processing part; by using a servo drive motor (not shown) to drive the gear 212, the positioning sleeve shaft 21 is caused to rotate relative to the cable transmission conduit 3 by an angle, and the deflection scanning housing 22 and the light detector 24 are also driven to rotate by a predetermined angle at the same time, thereby irradiating other directions of the cable 10 and detecting its eccentricity.

[0043] In the embodiment of the present invention, Figure 4 and Figure 8As shown, the light irradiation head 241 is a visible light irradiation head, and the light receiving part 242 is a visible light receiving head. The visible light irradiation head adopts an infrared irradiation lamp, and the visible light receiving head adopts an infrared CCD image sensor. The cable image data collected by the infrared CCD image sensor is uploaded to the central controller 110 for processing, and then sent to the host computer 113 for data processing and display and record detection results, so as to obtain the thickness of each layer and effectively measure the thickness or eccentricity of the cable insulation layer; because the infrared irradiation lamp and the infrared CCD image sensor are perpendicular to the cable 10 and in the same straight line, when the cable is irradiated with infrared light, due to the different materials of the cable, different parts of the cable absorb the infrared light differently. Part of the infrared light will pass through the insulation layer of the cable 10, while the infrared light cannot penetrate the cable core and is completely absorbed by the cable core, so that the infrared CCD image sensor detects different infrared image cable core shadows on the back of the cable 10, and the cable core part is completely formed into a black shadow. The shadow image of the insulation part and the shadow image of the cable core are respectively obtained, so that the width d of the shadow formed by the cable core part can be calculated, where the cable core width is determined by the maximum width d 1max and minimum width d 1min Composition, eccentricity d 1max -d 1min / d 1max ×100%, and then calculate the width D of the shadow formed by the cable insulation part. The width D of the cable insulation part is calculated by the maximum outer diameter width D 1max and minimum outer diameter width D 1min and the maximum inner diameter D 2max and minimum inner diameter width D 2min Composition, and then according to the eccentricity (degrees) = maximum thickness of insulation layer - minimum thickness of insulation layer / average outer diameter of insulation layer thickness, the maximum eccentricity of insulation layer is obtained as [(D 1max -D 2min )-(D 1min -D 2min )] / (D 1max +D 1min ) / 2×100%.

[0044] In the embodiment of the present invention, Figure 4 and Figure 8As shown, the light irradiation head 241 is an X-ray emitting head, which uses an X-ray irradiation tube, and the light receiving part 242 is an X-ray receiving head, which uses an X-ray photoelectric sensor. Since X-rays can penetrate objects that visible light cannot penetrate, when X-rays pass through the object to be measured, each part has different absorption capacity for the rays, thereby producing different attenuation effects on the X-rays. Different materials on the cable have different absorption rates or refractive indices for X-rays. When the X-rays penetrate the cable, different attenuations will occur due to the different absorption rates of the X-rays in each layer of the cable. Parts of the same material with a larger thickness will have a higher attenuation effect on the X-rays. The more the rays are absorbed, the greater the thickness they pass through, which causes the greater the degree of X-ray attenuation. When the X-ray emitter emits X-rays to scan vertically through the cable, the distribution of material and thickness-related information inside the cable is collected by the X-ray photoelectric sensor. The collected hierarchical structure diagram inside the cable is converted from an optical signal into an electrical signal for amplification, and then transmitted to the central controller 110 for AD conversion, filtering, and denoising. It is then sent to the host computer 113 for data processing and display of the recorded detection results, thereby obtaining the boundary distribution of the internal structure of the cable, and thus deriving the thickness of each layer, effectively measuring the thickness or eccentricity of the cable insulation layer.

[0045] According to another aspect of the present invention, Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 6 、 Figure 8 、 Figure 9 The present invention uses a power cable production deviation measurement system to measure the deviation of a cable, which includes the following steps:

[0046] Step 1: Distribute light detectors 24 on the outer wall of the positioning sleeve shaft 21 and within the deflection scanning housing 22 at a 120° angle along the pulling direction of the cable 10. Each light detector 24 is distributed on the periphery of the cable 10 from the input side to the output side of the positioning sleeve shaft 21. Each light detector 24 is perpendicular to the cable 10, and adjacent light detectors 24 form a 120° angle in space.

[0047] Step 2: The three-layer co-extruded cable is conveyed into the positioning sleeve shaft 21, and then sequentially conveyed into the cable conveying conduit 3 for traction and conveying. On the input side of the positioning sleeve shaft 21, a laser ranging sensor 112 is used to detect whether the upper and lower outer walls of the cable 10 are at the same distance from the radial edge of the positioning sleeve shaft 21, so that the cable 10 is respectively located at the center of the positioning sleeve shaft 21;

[0048] Step 3: In each deflection scanning housing, start the push rod motor 244 to push the sealed cavity 243 to slide in each deflection scanning housing 22, adjust the vertical distance between the light irradiation head 241 and the cable 10, and during the time interval of each radial edge distance detection by the laser ranging sensor 112, the three light irradiation heads 241 in the deflection scanning housing 22 will first emit irradiation light vertically to the cable 10 at different azimuth positions at the same time, forming a shadow on the back of the cable 10, and obtain the shadow image data generated when the three light irradiation heads 241 simultaneously and vertically illuminate different positions of the cable 10 through the light receiving part 242, so that the eccentricity within a certain unit length of the cable 10 can be detected; then the three light irradiation heads 241 in the deflection scanning housing 22 will be started in sequence from the input side to the output side of the positioning sleeve shaft 21. During the traction and transmission process of the cable 10, each light irradiation head 241 will emit irradiation light to the cable 10 in sequence and at different azimuths at a specified time interval. The irradiation light is emitted at the same position of the cable 10, and a shadow is also formed on the back of the cable 10; in an embodiment of the present invention, the light irradiation head 241 is an X-ray emitting head, and the light receiving part 242 is an X-ray receiving head. Since the light emitted by the light irradiation head 241 is perpendicular to the front side of the cable 10 during each irradiation, the irradiation light is blocked by the cable 10, and the part of the irradiation light at the edge of the back side of the cable 10 is received by the light receiving part 242, and the irradiation light blocked by the cable 10 forms a shadow on the back; when the irradiation scanning light is emitted to the same position of the cable, the light receiving part 242 at each position obtains the shadow image data or imaging picture of the same position of the cable 10 when irradiated at different times during the traction process, and obtains the shadow image data or imaging picture inside the cable from different angles, so as to fully understand the eccentricity of each position of the entire cable or the unit length of the cable during co-extrusion production, thereby improving the production efficiency and production quality of the cable;

[0049] Step 4: The light receiving part 242 transmits the shadow image data S1 generated at different positions to the central controller 110 for processing, and then uploads the processed shadow image data S1 generated at different positions to the host computer to calculate the width of the shadow image data S1 generated at different positions of the cable 10, and then calculates the first eccentricity of the cable according to the width of the shadow image data S1 generated at different positions and displays the calculation result; and each of the light receiving parts 242 transmits the shadow image data S2 generated at the same position to the central controller 110 for processing, and then uploads the processed shadow image data S2 at the same position to the host computer to calculate the width of the shadow image data S2 of the cable 10 obtained by each light receiving part 242, and then calculates the first eccentricity of the cable according to the width of the shadow image data S1 generated at the same position and displays the calculation result. The second eccentricity of the cable is calculated based on the width of the data S2 and the calculation result is displayed; the shadow image data of different positions during the first irradiation and the shadow image data of the same position during the second irradiation at a different time are transmitted to the central controller for processing, and then the processed shadow image data are uploaded to the host computer, and the width of each shadow image formed on the back of the cable 10 at different positions during the first irradiation is calculated respectively, and the width of the shadow image formed at the same position of the cable 10 at different orientations during the second irradiation is calculated, and the eccentricity of the cable at the same position is calculated based on the shadow width; thereby comprehensively evaluating the quality of online produced cables, improving the accuracy of cable eccentricity detection and the quality of cable production; in the present invention, calculating the second eccentricity of the cable based on the width of the shadow image data S2 generated at the same position includes the following steps:

[0050] In step 41, the central controller 110 obtains the time interval for the laser ranging sensor 112 to detect the cable 10. When the laser ranging sensor 112 detects the cable 10 within the time interval specified by the laser ranging sensor 112, the light irradiation head 241 emits an irradiation light to detect and scan the cable 10 while ensuring that the cable is at the center of the positioning sleeve shaft 21. At each moment within the specified time interval, the cable 10 is pulled and moved to the corresponding position of the light irradiation head 241 so that it can be irradiated and scanned at the same position and different orientations. After the cable is pulled to the position of the first light irradiation head 241 within the specified time interval, the cable 10 begins to be irradiated and scanned.

[0051] Step 42 , the central controller 110 obtains, through the three light receiving parts 242 , at different moments within a time interval, shadow images when the corresponding light irradiation head 241 irradiates the same position of the cable;

[0052] Step 43, respectively extracting the shadow image width D of the cable insulation layer and the shadow image width d of the cable core conductor obtained at the same position and time of each light receiving portion 242;

[0053] Step 44, performing difference calculations on the shadow image width D of the insulation layer and the shadow image width d of the cable core conductor with corresponding set thresholds, thereby removing image data of blurred portions in the shadow image, and obtaining a difference sequence width ΔD of the insulation layer and a difference sequence width Δd of the cable core conductor of the shadow image width at the same position and time;

[0054] Step 45: sort the insulation layer difference sequence width ΔD and the cable core conductor difference sequence width Δd, and extract the maximum value, minimum value and average value of the insulation layer difference sequence width ΔD, wherein the maximum value is determined by the maximum outer diameter width D. 1max and maximum inner diameter D 2max And the minimum value is determined by the minimum outer diameter width D 1min and minimum inner diameter width D 2min The eccentricity of the insulation layer and the maximum value (d 1max ) and minimum value (d 1min ) Calculate the eccentricity of the cable core conductor;

[0055] Step 5: The positioning sleeve shaft 21 is driven by the gear 212 to rotate relative to the cable transmission conduit 3 by an angle, and the deflection scanning housing 22 and the optical detector 24 are driven to rotate by a predetermined angle at the same time. Then the above steps are repeated to detect the eccentricity of the cable.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A power cable production deviation measurement system, characterized by: It includes a deflection measuring device installed on the output side of the multi-layer co-extruder and rotatably arranged along the cable pulling movement direction, a cable transmission conduit interconnected with the deflection measuring device, and a detection processing part communicatively connected to the deflection measuring device. The deflection measuring device includes a support frame, a positioning sleeve shaft, a deflection measuring scanning shell and a light detector. The two ends of the positioning sleeve shaft are rotatably arranged on the support frame through bearing seats respectively. Three deflection measuring scanning shells are arranged on the outer wall of the positioning sleeve shaft and extended along the cable pulling direction. They are connected at an angle of 120 degrees. A light detector is respectively arranged in each deflection measuring scanning shell. The light detectors in each deflection measuring scanning shell are not on the same vertical plane with each other, and are respectively distributed around the positioning sleeve shaft along the cable pulling direction. The laser detectors in adjacent deflection measuring scanning shells are spatially distributed at an angle of 120 degrees. The light detector is connected to the detection processing part. The detection and processing part includes a central controller, a communication module, a laser ranging sensor and a host computer. The central controller is communicatively connected to the host computer via the communication module. The light detector includes a light irradiation part and a light receiving part. The light irradiation part is composed of a power module and a light irradiation head. The power module is electrically connected to the light irradiation head. A sealed cavity sliding along the inner wall is provided in the deflection scanning housing. The power module is provided at the external top end of the sealed cavity. The light irradiation head of the light irradiation part is provided in the sealed cavity. The light receiving part is provided in front of the light projected by the light irradiation head and at the bottom of the sealed cavity perpendicular to the other side of the cable. The laser ranging sensors are symmetrically provided radially above and below the input side of the positioning sleeve shaft, respectively. The laser ranging sensor and the light receiving part are connected to the central controller. A fixed sleeve is coaxially arranged in front of the axial direction of the input side of the positioning sleeve shaft, the laser ranging sensor is arranged in the radial direction between the output side of the fixed sleeve and the input side of the positioning sleeve shaft, and an irradiation window for irradiation or scanning by a light irradiation head is provided on the outer wall of the positioning sleeve shaft and along the cable pulling movement direction; a rotating ring is sleeved on the outer wall of the output side of the positioning sleeve shaft, the output end of the positioning sleeve shaft is connected to the cable transmission conduit through the rotating ring, a gear is provided on the outer wall of the positioning sleeve shaft close to the rotating ring, and an angle sensor for detecting the rotation angle of the gear is provided on the gear, and the angle sensor is electrically connected to the detection processing part; A push rod motor is arranged in the deflection measurement scanning housing and directly in front of the top outer wall of the sealed cavity. The output shaft of the push rod motor is transmission-connected to the top outer wall of the sealed cavity. The fixed end of the push rod motor is arranged on the top inner wall of the deflection measurement scanning housing. The control end of the push rod motor is electrically connected to the central controller. The light irradiation head is a visible light irradiation head, which adopts an infrared irradiation lamp. The light receiving part is a visible light receiving head, which adopts an infrared CCD image sensor.

2. A power cable production deviation measurement system according to claim 1, characterized in that: A cooling cavity that is communicated with each other is arranged inside the top wall and the side wall of the sealing cavity, and the cooling cavity is filled with cooling liquid.

3. The power cable production deviation measurement system according to claim 1, characterized in that: The light irradiation head is an X-ray emitting head, which adopts an X-ray irradiation tube; the light receiving part is an X-ray receiving head, which adopts an X-ray photoelectric sensor.

4. A deviation measurement method for a power cable production deviation measurement system according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: Distribute photodetectors on the outer wall of the positioning sleeve shaft and within a deflection scanning housing at a 120° angle along the cable pulling direction. Each photodetector is distributed around the cable from the input side to the output side of the positioning sleeve shaft. Each photodetector is perpendicular to the cable, and adjacent photodetectors form a 120° angle in space. Step 2: The three-layer co-extruded cable is conveyed into the positioning sleeve shaft, and then sequentially fed into the cable conveying conduit for traction and conveying. On the input side of the positioning sleeve shaft, a laser distance measuring sensor is used to detect whether the upper and lower outer walls of the cable are at the same distance from the radial edge of the positioning sleeve shaft, so that the cables are respectively located at the center of the positioning sleeve shaft; Step 3: In each deflection measurement scanning housing, the push rod motor is started respectively to push the sealed cavity to slide in each deflection measurement scanning housing, and the vertical distance between the light irradiation head and the cable is adjusted. During each interval of the laser ranging sensor detecting the radial edge distance, the light irradiation heads in the three deflection measurement scanning housings first emit vertical irradiation light to the cable at different azimuth positions at the same time, forming a shadow on the back of the cable, and the shadow image data generated when the three light irradiation heads simultaneously and vertically irradiate different positions of the cable are obtained through the light receiving parts respectively; then the light irradiation heads in the three deflection measurement scanning housings are started in sequence from the input side to the output side of the positioning sleeve shaft. During the cable traction and transmission process, each light irradiation head emits irradiation light to the same position of the cable in sequence and at different azimuths at a specified time interval, and also forms a shadow on the back of the cable. The light receiving part at each position obtains the shadow image data generated when the cable irradiates the same position at different times during the traction process; Step 4: the light receiving part transmits the shadow image data S1 generated at different positions to the central controller for processing, and then uploads the processed shadow image data S1 generated at different positions to the host computer to calculate the width of the shadow image data S1 at different positions of the cable, and then calculates the first eccentricity of the cable according to the width of the shadow image data S1 generated at different positions and displays the calculation result; and each light receiving part transmits the shadow image data S2 generated at the same position to the central controller for processing, and then uploads the processed shadow image data S2 generated at the same position to the host computer to calculate the width of the shadow image data of the cable obtained by each light receiving part, and then calculates the second eccentricity of the cable according to the width of the shadow image data S2 generated at the same position and displays the calculation result, thereby obtaining the eccentricity of the same position when illuminated from different orientations; Step 5: The positioning sleeve shaft is driven to rotate relative to the cable transmission conduit by an angle through the driving gear, and the deflection scanning housing and the optical detector are driven to rotate at a predetermined angle at the same time. Then the above steps are repeated to detect the eccentricity of the cable.

5. The deviation measurement method according to claim 4, characterized in that: Calculating the second eccentricity of the cable according to the width of the shadow image data S2 generated at the same position in step 4 includes the following steps: Step 41, the central controller obtains the time interval of the laser ranging sensor detecting the cable; Step 42, the central controller obtains, through the three light receiving parts, shadow images when the corresponding light irradiation head irradiates the same position of the cable at different times within the time interval; Step 43, respectively extracting the shadow image width of the cable insulation layer and the shadow image width of the cable core conductor obtained at the same position and at the same time of each light receiving part; Step 44, performing difference calculations on the shadow image width of the insulation layer and the shadow image width of the cable core conductor with corresponding set thresholds, to obtain a difference sequence width of the insulation layer and a difference sequence width of the cable core conductor for the shadow image widths at the same position and time; Step 45, sorting the insulation layer difference sequence width and the cable core conductor difference sequence width, extracting the maximum value, minimum value and average value of the insulation layer difference sequence width, and calculating the eccentricity of the insulation layer based on the maximum value, minimum value and average value of the insulation layer difference sequence width, and calculating the eccentricity of the cable core conductor based on the maximum value and minimum value of the cable core conductor difference sequence width.

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