Conveyor belt surface defect detection device

Abstract

The invention discloses a conveyor belt surface defect detection device which is characterized in that the surface of a conveyor belt is divided into two batches of detection areas, an industrial camera carries out image capture on the two batches of detection areas in two times, and in the process, a corresponding scraper assembly is matched to peel off materials from the areas to be shot. The defect of material blocking is avoided, normal conveying of a non-detection area is not affected, and the problem of missing detection caused by material covering of a traditional device is solved; meanwhile, the rotary chain assembly drives the industrial cameras in the detection areas of the corresponding batches to move synchronously with the conveying belt, motion blur caused by high-speed operation is eliminated, the definition of image capture of the industrial cameras is improved, and the detection precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of belt conveying device, and particularly relates to a conveying belt surface defect detection device. BACKGROUND

[0002] As the core equipment for continuous material conveying in the industrial fields such as mines, ports, metallurgy and chemical industry, the running state of the conveying belt directly affects the production efficiency and operation safety. In the long-term use process, the surface of the conveying belt is prone to defects such as tearing, scratches, peeling of the adhesive layer and holes due to factors such as material impact, friction and aging. If not detected and processed in time, small defects may quickly expand into through damage, leading to belt rupture, material leakage and even equipment downtime, causing significant economic losses and safety hazards.

[0003] The existing conveying belt surface defect detection technology mainly includes manual detection and automatic detection. Manual detection relies on the naked eye observation of the operator or the use of simple tools for inspection, which has the problems of high labor intensity, low efficiency, high missed detection rate (especially for high-speed running belts or subtle defects), the need for downtime detection affecting production, and the difficulty in meeting the continuous production needs of modern industry.

[0004] To solve the problems of manual detection, automatic detection technology has been gradually developed, and the detection scheme based on machine vision is widely researched and applied due to its moderate cost and strong intuitiveness. The existing visual detection device usually adopts a fixedly installed industrial camera to shoot the surface of the belt, and analyzes the defects through an image recognition algorithm. However, in actual application, such device has the following significant technical bottlenecks: 1) Serious material shielding interference: The surface of the conveying belt usually carries a large amount of material during dynamic operation, which causes the defects on the surface of the belt to be shielded, resulting in a detection blind area, and the camera cannot effectively capture the defect image, which may cause missed detection.

[0005] 2) Dynamic shooting blur problem: The running speed of the conveying belt is generally 0.5-5 m / s, and the camera is in a fixed state during shooting. There is relative motion between the surface of the conveying belt and the camera, and the captured image is prone to motion blur, which may cause subtle defects to be unable to be identified, resulting in insufficient detection accuracy.

[0006] In summary, the existing machine vision detection scheme has the problems that the conveying belt has a detection blind area due to material shielding, and the image captured by the camera is prone to motion blur, which may cause subtle defects to be unable to be identified. SUMMARY

[0007] The present application aims to provide a conveying belt surface defect detection device, which solves the technical problems in the prior art that the conveying belt has a detection blind area due to material shielding during machine vision detection, and the image captured by the camera is prone to motion blur, which may cause subtle defects to be unable to be identified.

[0008] To solve the above technical problems, the present application specifically provides the following technical solutions: A conveying belt surface defect detection device, comprising: a plurality of industrial cameras arranged above the conveying belt through a support, the camera of the industrial camera is arranged towards the conveying belt for capturing the surface texture image of the conveying belt; a detection area, the surface of the conveying belt is divided into a plurality of long strip-shaped detection areas along the rotation direction of the conveying belt, wherein the detection areas in odd order are the first batch of detection areas, and the detection areas in even order are the second batch of detection areas, the plurality of industrial cameras are divided into two groups, and the surface of the first batch of detection areas and the second batch of detection areas on the conveying belt is captured by image in different positions; a rotating chain assembly, one rotating chain assembly consistent with the rotation direction of the conveying belt is arranged on the support corresponding to the two detection positions of the industrial camera, and each rotating chain assembly drives the equidistant movement of the corresponding group of industrial cameras, so that the industrial cameras move synchronously with the conveying belt when capturing the surface image of the conveying belt; a scraper assembly, one scraper assembly is arranged corresponding to each detection area, the scraper assembly is arranged on the support, the bottom of the scraper assembly is in contact with the conveying belt to strip the material carried by the conveying belt in the corresponding detection area; wherein the scraper assembly is arranged upstream of the detection position corresponding to the industrial camera.

[0009] Further, the support is provided with a connecting rod perpendicular to the rotation direction of the conveying belt at the detection starting point of the first batch of detection areas and the detection starting point of the second batch of detection areas, and the corresponding scraper assembly of the first batch of detection areas and the second batch of detection areas is arranged on the corresponding connecting rod.

[0010] Further, the scraper assembly comprises two scrapers, the two scrapers are symmetrically arranged, one end is connected and the other end is opened to form an acute angle structure, and the acute angle end of the scraper assembly is arranged towards the material direction.

[0011] Further, the distance between the two opened scraper ends of the scraper assembly is greater than the width of the corresponding detection area.

[0012] Further, the bottom of the scraper is provided with a flexible strip abutting against the conveying belt.

[0013] Further, a conductive fiber wire is implanted in the flexible strip along the horizontal direction, both ends of the conductive fiber wire are connected to the detection circuit through a wire, a detection unit in the detection circuit is electrically connected to a controller, and the conductive fiber wire is arranged to be broken due to wear when the bottom of the flexible strip is worn to have a gap with the conveying belt, so as to cause the conduction state of the detection circuit to change, and the controller triggers an audible and light warning.

[0014] Furthermore, a pressure plate is provided at the top of the flexible strip, and the pressure plate is detachably connected to the scraper by bolts.

[0015] Furthermore, the rotary chain assembly includes two symmetrically arranged rotary chains, one end of which is provided with a driving sprocket and the other end with a driven sprocket. The two driving sprockets and the two driven sprockets are connected by a connecting shaft, and one of the driving sprockets is driven to rotate by a motor. The two rotary chains are connected by support rods that are set at equal intervals, and the industrial camera is mounted on the support rods.

[0016] Furthermore, the industrial camera is equipped with a conductive connector, and the bracket is provided with a circular conductive groove along the moving trajectory of the conductive connector. The conductive groove is connected to an external circuit. The conductive connector is locked in the conductive groove and can move along the conductive groove, so that the circuit remains connected while the multiple industrial cameras are driven by the rotary chain assembly to rotate in sequence.

[0017] Furthermore, the inner walls on both sides of the slide correspond to the positive and negative terminals of the power supply, respectively, and the side wall of the conductive connector is provided with two elastic contacts that can respectively abut against and be electrically connected to the inner walls on both sides of the slide.

[0018] Compared with the prior art, the present invention has the following advantages: The present invention provides a conveyor belt surface defect detection device, which divides the surface of the conveyor belt into two batches of detection areas. An industrial camera captures images of the two batches of detection areas in two separate steps. During the process, a corresponding scraper assembly peels off the material in the area to be photographed, which not only avoids the material from obscuring the defects, but also does not affect the normal conveying of non-detection areas, thus solving the problem of missed detection caused by material covering in traditional devices.

[0019] Meanwhile, by driving the industrial camera and the conveyor belt to move synchronously through the rotary chain assembly, motion blur caused by high-speed operation is eliminated, improving the clarity of the industrial camera image capture and providing detection accuracy. Attached Figure Description

[0020] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a conveyor belt surface defect detection device. Figure 2 This is a schematic diagram showing the distribution of the inspection areas on the surface of the conveyor belt; Figure 3 This is a schematic diagram of the rotary chain assembly. Figure 4 This is a schematic diagram of the scraper assembly.

[0022] The labels in the diagram represent the following: 1-Bracket, 2-Industrial camera, 3-Detection area, 4-Rotary chain assembly, 5-Scraper assembly; 31 - First batch testing area; 32 - Second batch testing area; 51-Connecting rod, 52-Scraper, 53-Flexible strip, 54-Conductive fiber filament, 55-Pressure plate, 56-Bolt; 41-Swivel chain, 42-Drive sprocket, 43-Moving sprocket, 44-Connecting shaft, 45-Support rod; 21-Conductive connector, 22-Conductive groove, 23-Resilient contact, 24-Base. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] like Figure 1 As shown, the present invention provides an implementation method for a conveyor belt surface defect detection device. The main method is to divide the surface of the conveyor belt into two batches of detection areas 3. An industrial camera 2 captures images of one batch of detection areas 3 in two separate steps. During the process, a corresponding scraper assembly 5 peels off the material in the area to be photographed to remove blind spots in the detection. At the same time, the industrial camera 2 is driven to move synchronously with the conveyor belt by a rotary chain assembly 4, which eliminates motion blur caused by high-speed operation.

[0025] Multiple industrial cameras 2 are mounted above the conveyor belt via bracket 1, with the camera lens of the industrial camera 2 facing the conveyor belt to capture images of the surface texture of the conveyor belt.

[0026] Industrial Camera 2 uses a high-resolution CCD camera with a lens focal length matched to the shooting distance to ensure that the field of view of a single camera covers the width of the conveyor belt; it is also equipped with a ring LED supplementary light module to ensure uniform illumination on the belt surface and eliminate material shadow interference.

[0027] like Figure 2As shown, the surface of the conveyor belt is divided into multiple long strip-shaped detection areas 3 along the rotation direction of the conveyor belt. The area numbers are arranged in sequence as 1#, 2#, 3#..., with odd-numbered areas being the first batch and even-numbered areas being the second batch. The two batches of areas are distributed alternately, together covering the full width of the belt.

[0028] Multiple industrial cameras 2 are divided into two groups to capture images of the surface of the first batch inspection area 31 and the second batch inspection area 32 on the conveyor belt, respectively.

[0029] Each detection area 3 is equipped with a scraper assembly 5, which is mounted on the support 1. The bottom of the scraper assembly 5 contacts the conveyor belt to peel off the material carried by the conveyor belt in the corresponding detection area 3. The scraper assembly 5 corresponding to the first batch of detection area 31 is set at the detection starting point of the first batch of detection area 31, and the scraper assembly 5 corresponding to the second batch of detection area 32 is set at the detection starting point of the second batch of detection area 32.

[0030] The detection starting point is 5-10cm upstream of the location where industrial camera 2 begins to capture the area, ensuring that the material on the belt surface is stripped off before entering the camera's field of view.

[0031] Specifically, the testing processes of the first batch testing area 31 and the second batch testing area 32 are carried out alternately. For example, when testing the first batch testing area 31, the material carried by the conveyor belt in the corresponding testing area 3 is stripped by the corresponding scraper assembly 5, and the material is conveyed normally in the second batch area; and vice versa, to ensure that the belt always keeps conveying continuously and does not affect production efficiency.

[0032] On the support 1 above the first batch inspection area 31 and the second batch inspection area 32, a rotary chain assembly 4 is set in the same direction as the rotation of the conveyor belt. Each rotary chain assembly 4 drives a corresponding set of industrial cameras 2 to move at equal intervals, so that when the industrial cameras 2 capture images of the surface of the conveyor belt, they move synchronously with the conveyor belt.

[0033] Specifically, the spacing between adjacent industrial cameras 2 is determined according to the coverage of industrial cameras 2, so that the images captured by adjacent industrial cameras 2 overlap in the length direction.

[0034] This embodiment provides an example of scraper assembly 5.

[0035] like Figure 4 As shown, the bracket 1 has a connecting rod 51 perpendicular to the rotation direction of the conveyor belt at the starting point of the first batch detection area 31 and the starting point of the second batch detection area 32 along the horizontal plane. The scraper assemblies 5 corresponding to the first batch detection area 31 and the second batch detection area 32 are all set on the corresponding connecting rod 51.

[0036] Specifically, the connecting rod 51 rigidly connects the scraper assembly 5 corresponding to the same batch of inspection area 3 to prevent individual scrapers 52 from shifting due to vibration or material impact.

[0037] Furthermore, the scraper assembly 5 includes two scrapers 52, which are symmetrically arranged and connected at one end to form an acute angle structure at the other end. The acute angle end of the scraper assembly 5 is set towards the material feeding direction.

[0038] When the conveyor belt carries the material to the detection starting point, the front end of the acute angle structure of the scraper assembly 5 contacts the material first, diverting the material to both sides. The material slides along the surface of the scraper 52 to the detection area 3 of a different batch. For example, the scraper 52 of the first batch pushes the material to the second batch area, preventing the material from accumulating above the detection area 3.

[0039] Furthermore, the distance between the ends of the two open scraper blades 52 of the scraper assembly 5 is greater than the width of the corresponding detection area 3. The excess scraper blades 52 can guide the stripped material to the detection area 3 of the next batch further away, preventing the material from flowing back to the already cleaned detection area 3 of this batch.

[0040] Furthermore, the bottom of the scraper 52 is provided with a flexible strip 53 that abuts against the conveyor belt.

[0041] The flexible strip 53 is made of polyurethane. The bottom of the flexible strip 53 is processed into a micro-arc shape, and the contact with the belt surface is a line contact, which not only ensures the sealing effect but also reduces frictional resistance. At the same time, the flexible strip 53 can produce elastic deformation with the slight undulations of the belt surface, such as joints and slight deformations, to ensure close contact in concave and convex areas and eliminate cleaning dead corners.

[0042] Furthermore, to prevent the scraper assembly 5 from guiding the material to the outside of the conveyor belt, skirts are provided on both sides of the conveyor belt to shield the material.

[0043] During use, the bottom of the flexible strip 53 will wear down, resulting in a gap between the flexible strip 53 and the conveyor belt. Therefore, the following embodiment is provided.

[0044] Conductive fiber filaments 54 are implanted horizontally inside the flexible strip 53. The two ends of the conductive fiber filaments 54 are connected to the detection circuit through wires. The detection unit in the detection circuit is electrically connected to the controller. The conductive fiber filaments 54 are configured such that when the flexible strip 53 wears down to the point where there is a gap between its bottom and the conveyor belt, the conductive fiber filaments 54 break due to wear, causing a change in the conduction state of the detection circuit, and the controller triggers an audible and visual warning.

[0045] Specifically, the fiber filaments are only 1-2mm away from the bottom friction surface of the flexible strip 53, ensuring that the fiber filaments will only break when the flexible strip 53 is worn to the point where it is about to be worn through and needs to be replaced.

[0046] The detection unit uses a current sensor or voltage comparator to monitor the circuit status in real time: when the fiber is intact, the circuit is open and the detection unit outputs a "high level" normal current signal; when the fiber is broken, the circuit is broken and outputs a "low level" or zero current signal.

[0047] The controller detects this change in status and determines that the flexible strip 53 has worn down to the critical thickness. It immediately triggers an audible and visual warning, such as a flashing red indicator light and a buzzer alarm, to prompt maintenance personnel to replace the flexible strip 53.

[0048] Furthermore, in this embodiment, in order to facilitate the replacement of the flexible strip 53, the top of the flexible strip 53 is pressed together with the bottom of the scraper 52 via a pressure plate 55, and the pressure plate 55 is detachably connected to the scraper 52 via bolts 56.

[0049] Specifically, the flexible strip 53, the pressure plate 55, and the scraper 52 are each provided with at least two sets of through holes. The bolts 56 are passed through the through holes in sequence and fixed by the nuts and threads, so as to press the pressure plate 55 and the scraper 52 together to fix the flexible strip 53.

[0050] This implementation also provides an embodiment of the rotary chain assembly 4.

[0051] like Figure 3 As shown, the rotary chain assembly 4 includes two symmetrically arranged rotary chains 41. One end of the rotary chain 41 is provided with a drive sprocket 42, and the other end is provided with a driven sprocket 43. The two drive sprockets 42 and the two driven sprockets 43 are connected by a connecting shaft 44, and one of the drive sprockets 42 is driven to rotate by a motor.

[0052] The motor is connected to one of the drive sprockets 42 via a reducer. Through the linkage of the connecting shaft 44, the drive sprockets 42 on both sides rotate synchronously, thereby driving the two rotating chains 41 to move synchronously.

[0053] The two rotating chains 41 are connected by support rods 45 that are set at equal intervals, and the industrial camera 2 is mounted on the support rods 45.

[0054] Specifically, each industrial camera 2 is provided with two support rods 45. The industrial camera 2 has two through holes, through which the support rods 45 are installed and welded and fixed. The ends of the two support rods 45 are welded and fixed to the same chain plate.

[0055] The industrial camera 2 is detachably connected to the base 24, facilitating the repair or replacement of the industrial rubber.

[0056] To address the circuit connectivity issue when the industrial camera 2 moves with the rotating chain 41, this embodiment also provides the following examples.

[0057] The industrial camera 2 is equipped with a conductive connector 21. The bracket 1 has a circular conductive groove 22 along the moving trajectory of the conductive connector 21. The conductive groove 22 is connected to the external circuit. The conductive connector 21 is stuck in the conductive groove 22 and can move along the conductive groove 22, so that the circuit is always connected when multiple industrial cameras 2 are driven by the rotary chain assembly 4 to rotate in sequence.

[0058] Specifically, the inner walls on both sides of the slide correspond to the positive and negative terminals of the power supply, respectively; the side wall of the industrial camera 2 is provided with a conductive connector 21 that connects to the end of the cable, and the end of the connector is provided with two elastic contacts 23 that abut against the inner walls on both sides of the slide.

[0059] The signal transmission of industrial camera 2 is wireless.

[0060] The above embodiments are merely exemplary embodiments of this application and are not intended to limit this application. The scope of protection of this application is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to this application within its substance and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of this application.

Claims

1. A device for detecting surface defects in a conveyor belt, characterized in that, include: Multiple industrial cameras (2) are mounted above the conveyor belt via a bracket (1), with the camera of each industrial camera (2) facing the conveyor belt to capture images of the surface texture of the conveyor belt; The detection area (3) is divided into multiple strip-shaped detection areas (3) along the rotation direction of the conveyor belt. The detection areas (3) located in odd-numbered positions are the first batch of detection areas (31), and the detection areas (3) located in even-numbered positions are the second batch of detection areas (3). Multiple industrial cameras (2) are divided into two groups and capture images of the surfaces of the first batch of detection areas (31) and the second batch of detection areas (32) on the conveyor belt at different positions. Rotary chain assembly (4): On the bracket (1), a rotary chain assembly (4) is set at each of the two detection positions corresponding to the industrial camera (2) and the rotation direction of the conveyor belt is consistent. Each rotary chain assembly (4) drives a set of industrial cameras (2) to move at equal intervals, so that when the industrial camera (2) captures the image of the conveyor belt surface, it moves synchronously with the conveyor belt. Scraper assembly (5), one scraper assembly (5) is provided for each detection area (3), the scraper assembly (5) is provided on the bracket (1), the bottom of the scraper assembly (5) is in contact with the conveyor belt to peel off the material carried by the conveyor belt in the corresponding detection area (3); wherein, the scraper assembly (5) is provided upstream of the detection position of the industrial camera (2).

2. The conveyor belt surface defect detection device according to claim 1, characterized in that, The bracket (1) has a connecting rod (51) perpendicular to the rotation direction of the conveyor belt at the detection starting point of the first batch detection area (31) and the detection starting point of the second batch detection area (32) along the horizontal plane. The scraper assembly (5) corresponding to the first batch detection area (31) and the second batch detection area (32) is set on the corresponding connecting rod (51).

3. The conveyor belt surface defect detection device according to claim 2, characterized in that, The scraper assembly (5) includes two scrapers (52), which are symmetrically arranged and connected at one end and open at the other end to form an acute angle structure. The acute angle end of the scraper assembly (5) is set towards the material inlet direction.

4. The conveyor belt surface defect detection device according to claim 3, characterized in that, The distance between the two ends of the scraper (52) of the scraper assembly (5) is greater than the width of the corresponding detection area (3).

5. The conveyor belt surface defect detection device according to claim 4, characterized in that, The bottom of the scraper (52) is provided with a flexible strip (53) that abuts against the conveyor belt.

6. The conveyor belt surface defect detection device according to claim 5, characterized in that, The flexible strip (53) has a conductive fiber filament (54) implanted in the horizontal direction. The two ends of the conductive fiber filament (54) are connected to the detection circuit through wires. The detection unit in the detection circuit is electrically connected to the controller. The conductive fiber filament (54) is configured such that when the flexible strip (53) wears down to the point where there is a gap between its bottom and the conveyor belt, the conductive fiber filament (54) breaks due to wear, causing the detection circuit to change its conduction state, and the controller triggers an audible and visual warning.

7. The conveyor belt surface defect detection device according to claim 6, characterized in that, The top of the flexible strip (53) is pressed against the bottom of the scraper (52) by a pressure plate (55), and the pressure plate (55) and the scraper (52) are detachably connected by bolts (56).

8. The conveyor belt surface defect detection device according to claim 1 or 6, characterized in that, The rotary chain assembly (4) includes two symmetrically arranged rotary chains (41). One end of each rotary chain (41) is provided with a drive sprocket (42), and the other end is provided with a driven sprocket (43). The two drive sprockets (42) and the two driven sprockets (43) are connected by a connecting shaft (44). One of the drive sprockets (42) is driven to rotate by a motor. The two rotary chains (41) are connected by support rods (45) that are set at equal intervals, and the industrial camera (2) is mounted on the support rods (45).

9. The conveyor belt surface defect detection device according to claim 7, characterized in that, The industrial camera (2) is provided with a conductive connector (21). The bracket (1) is provided with a circular conductive groove (22) along the moving trajectory of the conductive connector (21). The conductive groove (22) is connected to an external circuit. The conductive connector (21) is stuck in the conductive groove (22) and can move along the conductive groove (22), so that the circuit is always connected when the multiple industrial cameras (2) are driven by the rotary chain assembly (4) to rotate in sequence.

10. The conveyor belt surface defect detection device according to claim 8, characterized in that, The inner walls on both sides of the slide correspond to the positive and negative terminals of the power supply, respectively. The side wall of the conductive connector (21) is provided with two elastic contacts (23) that can abut against and be electrically connected to the inner walls on both sides of the slide.

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