A machine vision-based plastic pipe surface defect detection device

Abstract

The utility model discloses a kind of plastic pipe surface defect detection devices based on machine vision, it is related to surface defect detection technical field, including front frame and rear frame, the rear frame is set to the rear of front frame, the left end of front frame is fixedly connected with front fixed plate, rear fixed plate is arranged in the rear of front fixed plate, the front end of front fixed plate is fixedly installed with step motor, the output end of step motor is through the front end of front fixed plate and is fixedly connected with rotating shaft, the other end of rotating shaft is rotatably connected with the front end of rear fixed plate, four detection cameras are installed around pipe body in detection ring, ensure that the whole surface is continuously scanned, the angle of light is adjusted by rotating light component around pipe body, ensure that the brightness of each place on pipe surface is consistent, reduce shadow interference, pipe body is fixed by pressing plate component and V-shaped supporting roller cooperation, enhance the stability of device.

Description

Technical Field

[0001] This utility model relates to the field of surface defect detection technology, specifically to a machine vision-based device for detecting surface defects in plastic pipes. Background Technology

[0002] Plastic pipes are hollow, continuous profiles made primarily from high-molecular resins such as polyvinyl chloride, polyethylene, and polypropylene, through processes including extrusion, cooling, and sizing. Compared to traditional metal and cement pipes, they offer advantages such as corrosion resistance, rust prevention, and ease of installation. Before being put into use, plastic pipes require surface defect inspection.

[0003] Traditional devices typically use a single-point camera and a fixed light source. The camera cannot cover the 360° surface of the pipe, and the fixed light source is prone to creating shadows or blind spots during illumination, making it difficult for the camera to capture minute defects. Furthermore, the pipe is prone to shaking during transportation, which can cause image blurring or interruption of detection. To address these issues, a machine vision-based plastic pipe surface defect detection device is proposed. Utility Model Content

[0004] To address the aforementioned technical problems, a machine vision-based plastic pipe surface defect detection device is provided. This technical solution solves the problems mentioned in the background art, such as the difficulty of capturing minute defects with a fixed light source and the image blurring caused by pipe shaking.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a machine vision-based plastic pipe surface defect detection device, comprising a front frame and a rear frame, wherein the rear frame is disposed behind the front frame, a front fixing plate is fixedly connected to the left end of the front frame, a rear fixing plate is disposed behind the front fixing plate, a stepper motor is fixedly mounted on the front end of the front fixing plate, the output end of the stepper motor passes through the front end of the front fixing plate and is fixedly connected to a rotating shaft, the other end of the rotating shaft is rotatably connected to the front end of the rear fixing plate, and the outer surface of the rotating shaft is fixedly connected to... The device includes an active roller. Two fixed frames are fixedly connected to the top of the front and rear frames. A pressure plate assembly is provided on the inner side of the fixed frame. The main body of the pipe is provided below the pressure plate assembly. A detection ring is provided between the front and rear frames. Two connecting plates are fixedly connected to the outer surface of the detection ring. The two connecting plates are fixedly connected to the rear end of the front frame and the front end of the rear frame, respectively. Four detection cameras are fixedly installed on the inner surface of the detection ring. A ring-shaped supplementary light strip is fixedly connected to the left end of the detection ring. A rotating light assembly is provided at the right end of the detection ring.

[0006] Preferably, a driven roller is provided on the right side of the front frame.

[0007] Preferably, multiple V-shaped rollers are provided on the left and right sides of the detection ring between the front frame and the rear frame, and the main body of the pipe is connected to the upper end of the V-shaped rollers.

[0008] Preferably, the pressure plate assembly includes a cylinder and a guide rail. The cylinder is fixedly installed on the top of the fixed frame, and the guide rail is fixedly connected to the inner top of the fixed frame. The output end of the cylinder passes through the upper end of the fixed frame and the guide rail and is fixedly connected to a guide rod. The guide rod is slidably connected to the inside of the guide rail, and the lower end of the guide rod is fixedly connected to a U-shaped pressure plate.

[0009] Preferably, a rubber pad is provided on the lower surface of the U-shaped pressure plate.

[0010] Preferably, the rotating light assembly includes a mounting plate and a servo motor. The mounting plate is fixedly connected to the rear end of the front frame, located on the right side of the connecting plate. The servo motor is fixedly mounted on the right end of the mounting plate. The output end of the servo motor passes through the right end of the mounting plate and is fixedly connected to a drive rod. A groove is provided on the right side of the detection ring. A gear ring is rotatably connected inside the groove. A drive gear meshes with the outer surface of the gear ring. The other end of the drive rod is fixedly connected to the axis of the drive gear. An LED light is fixedly connected to the right end of the gear ring.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: four detection cameras are installed around the pipe body in the detection ring to ensure that the entire surface is continuously scanned; the angle of the light is adjusted by rotating the light assembly around the pipe body, and basic lighting is provided by the ring-shaped supplementary light strip to ensure that the brightness of the pipe surface is consistent and reduce shadow interference; the pipe body is fixed by the pressure plate assembly and V-shaped rollers, which enhances the stability of the device. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a three-dimensional structural diagram of the present invention from another perspective; Figure 3 for Figure 1 A magnified view of a portion of point A in the middle; Figure 4 for Figure 1 A magnified view of a portion of point B in the middle; Figure 5 This is a schematic diagram of the detection ring in this utility model.

[0013] The numbers on the map are: 1. Front frame; 2. Rear frame; 3. Front fixing plate; 4. Rear fixing plate; 5. Stepper motor; 6. Rotary shaft; 7. Drive roller; 8. Fixing frame; 9. Pressure plate assembly; 901. Cylinder; 902. Guide rail; 903. Guide rod; 904. U-shaped pressure plate; 10. Pipe body; 11. Detection ring; 12. Connecting plate; 13. Detection camera; 14. Circular supplementary light strip; 15. Rotating light assembly; 1501. Mounting plate; 1502. Servo motor; 1503. Drive rod; 1504. Groove; 1505. Gear ring; 1506. Drive gear; 1507. LED light; 16. Driven roller; 17. V-shaped idler roller; 18. Rubber pad. Detailed Implementation

[0014] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0015] Reference Figures 1-5 As shown, a machine vision-based plastic pipe surface defect detection device includes a front frame 1 and a rear frame 2. The rear frame 2 is located behind the front frame 1. A front fixed plate 3 is fixedly connected to the left end of the front frame 1. A driven roller 16 is located on the right side of the front frame 1. A rear fixed plate 4 is located behind the front fixed plate 3. A stepper motor 5 is fixedly installed at the front end of the front fixed plate 3. The output end of the stepper motor 5 passes through the front end of the front fixed plate 3 and is fixedly connected to a rotating shaft 6. The other end of the rotating shaft 6 is rotatably connected to the front end of the rear fixed plate 4. An active roller 7 is fixedly connected to the outer surface of the rotating shaft 6. Two fixed frames 8 are fixedly connected to the top of the front frame 1 and the rear frame 2. A pressure plate assembly 9 is located on the inner side of the fixed frame 8. Furthermore, the pressure plate assembly 9 includes a cylinder 901 and a guide rail 902. The cylinder 901 is fixedly installed on the top of the fixed frame 8, and the guide rail 902 is fixedly connected to the inner top of the fixed frame 8. The output end of the cylinder 901 passes through the upper ends of the fixed frame 8 and the guide rail 902 and is fixedly connected to a guide rod 903. The guide rod 903 is slidably connected to the inside of the guide rail 902, and the lower end of the guide rod 903 is fixedly connected to a U-shaped pressure plate 904. When the cylinder 901 is activated, it pushes the guide rod 903 down along the guide rail 902, thereby driving the U-shaped pressure plate 904 to move downward. The pressure plate 904 presses the pipe tightly. A rubber pad 18 is provided on the lower surface of the U-shaped pressure plate 904. The rubber pad 18 is provided to prevent the metal pressure plate from directly damaging the plastic pipe wall and to reduce surface indentations or deformation. The pipe body 10 is located below the pressure plate assembly 9. Multiple V-shaped rollers 17 are arranged between the front frame 1 and the rear frame 2 on the left and right sides of the detection ring 11. The pressure plate assembly 9 and the V-shaped rollers 17 work together to fix the pipe body 10, enhancing the stability of the device. The pipe body 10 is connected to the upper part of the V-shaped rollers 17. At the end, the pipe body 10 is placed on the upper end of the V-shaped roller 17. The V-shaped roller 17 automatically adapts to the pipe diameter to ensure the axis is horizontal. The driven roller 16 and the driving roller 7 respectively contact the outer surface of the pipe, driving the pipe body 10 to move. A detection ring 11 is set between the front frame 1 and the rear frame 2. Two connecting plates 12 are fixedly connected to the outer surface of the detection ring 11. The two connecting plates 12 are fixedly connected to the rear end of the front frame 1 and the front end of the rear frame 2, respectively. Four detection cameras 13 are fixedly installed on the inner surface of the detection ring 11. Four inspection cameras 13 are installed around the pipe body 10 inside the inspection ring 11. The four inspection cameras 13 are fixed to the inner wall of the inspection ring 11 at 90° intervals to ensure that the entire surface is continuously scanned. A ring-shaped supplementary light strip 14 is fixedly connected to the left end of the inspection ring 11, and a rotating light assembly 15 is provided at the right end of the inspection ring 11. The angle of the light is adjusted by rotating the rotating light assembly 15 around the pipe body 10. Combined with the ring-shaped supplementary light strip 14, basic lighting is provided to ensure that the brightness of the pipe surface is consistent and to reduce shadow interference. Furthermore, the rotating light assembly 15 includes a mounting plate 1501 and a servo motor 1502. The mounting plate 1501 is fixedly connected to the rear end of the front frame 1, located on the right side of the connecting plate 12. The servo motor 1502 is fixedly mounted on the right end of the mounting plate 1501. The output end of the servo motor 1502 passes through the right end of the mounting plate 1501 and is fixedly connected to a drive rod 1503. A groove 1504 is provided on the right side of the detection ring 11. A toothed ring 1505 is rotatably connected inside the groove 1504. The outer surface of 505 is meshed with a drive gear 1506. Both the drive gear 1506 and the gear ring 1505 are provided with protective shells to prevent contaminants from entering the transmission system and to ensure long-term precise meshing of the gears. The other end of the drive rod 1503 is fixedly connected to the shaft of the drive gear 1506. An LED light 1507 is fixedly connected to the right end of the gear ring 1505. When the servo motor 1502 is started, it drives the drive gear 1506 to mesh with the gear ring 1505, causing the LED light 1507 to rotate and illuminate the shaded area.

[0016] The usage process of this utility model is as follows: First, the pipe body 10 is placed on the upper end of the V-shaped roller 17. The V-shaped roller 17 automatically adapts to the pipe diameter to ensure that the axis is horizontal. The driven roller 16 and the driving roller 7 respectively contact the outer surface of the pipe to drive the pipe body 10 to move. Then, the cylinder 901 is started to push the guide rod 903 to move down along the guide rail 902, which drives the U-shaped pressure plate 904 to press the pipe. Basic lighting is provided by turning on the ring supplement light strip 14. Then, the servo motor 1502 is started to drive the driving gear 1506 to mesh with the gear ring 1505, thereby driving the LED light 1507 to rotate and illuminate the shadow area. The four detection cameras 13 simultaneously take pictures of the pipe surface to detect pipe defects.

[0017] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A machine vision-based surface defect detection device for plastic pipes, comprising a front frame (1) and a rear frame (2), characterized in that: The rear frame (2) is located behind the front frame (1). A front fixing plate (3) is fixedly connected to the left end of the front frame (1). A rear fixing plate (4) is located behind the front fixing plate (3). A stepper motor (5) is fixedly installed at the front end of the front fixing plate (3). The output end of the stepper motor (5) passes through the front end of the front fixing plate (3) and is fixedly connected to a rotating shaft (6). The other end of the rotating shaft (6) is rotatably connected to the front end of the rear fixing plate (4). An active roller (7) is fixedly connected to the outer surface of the rotating shaft (6). Two fixing brackets (8) are fixedly connected to the top ends of the front frame (1) and the rear frame (2). A pressure plate assembly (9) is provided on the inner side of the fixed frame (8). A pipe body (10) is provided below the pressure plate assembly (9). A detection ring (11) is provided between the front frame (1) and the rear frame (2). Two connecting plates (12) are fixedly connected to the outer surface of the detection ring (11). The two connecting plates (12) are fixedly connected to the rear end of the front frame (1) and the front end of the rear frame (2) respectively. Four detection cameras (13) are fixedly installed on the inner surface of the detection ring (11). A ring-shaped supplementary light strip (14) is fixedly connected to the left end of the detection ring (11). A rotating light assembly (15) is provided at the right end of the detection ring (11).

2. The machine vision-based plastic pipe surface defect detection device according to claim 1, characterized in that: A driven roller (16) is provided on the right side of the front frame (1).

3. The machine vision-based plastic pipe surface defect detection device according to claim 1, characterized in that: Multiple V-shaped rollers (17) are provided between the front frame (1) and the rear frame (2) on the left and right sides of the detection ring (11), and the main body of the pipe (10) is connected to the upper end of the V-shaped rollers (17).

4. The machine vision-based plastic pipe surface defect detection device according to claim 1, characterized in that: The pressure plate assembly (9) includes a cylinder (901) and a guide rail (902). The cylinder (901) is fixedly installed on the top of the fixed frame (8). The guide rail (902) is fixedly connected to the top inner side of the fixed frame (8). The output end of the cylinder (901) passes through the upper end of the fixed frame (8) and the guide rail (902) and is fixedly connected to a guide rod (903). The guide rod (903) is slidably connected to the inside of the guide rail (902). The lower end of the guide rod (903) is fixedly connected to a U-shaped pressure plate (904).

5. The machine vision-based plastic pipe surface defect detection device according to claim 4, characterized in that: A rubber pad (18) is provided on the lower surface of the U-shaped pressure plate (904).

6. The machine vision-based plastic pipe surface defect detection device according to claim 1, characterized in that: The rotating light assembly (15) includes a mounting plate (1501) and a servo motor (1502). The mounting plate (1501) is fixedly connected to the rear end of the front frame (1) and located on the right side of the connecting plate (12). The servo motor (1502) is fixedly installed on the right end of the mounting plate (1501). The output end of the servo motor (1502) passes through the right end of the mounting plate (1501) and is fixedly connected to a drive rod (1503). A groove (1504) is provided on the right side of the detection ring (11). A gear ring (1505) is rotatably connected inside the groove (1504). A drive gear (1506) meshes with the outer surface of the gear ring (1505). The other end of the drive rod (1503) is fixedly connected to the axis of the drive gear (1506). An LED light (1507) is fixedly connected to the right end of the gear ring (1505).

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