A device for detecting defects of a plastic product
By combining adaptive illumination and an active switching mechanism, the accuracy and versatility issues of existing devices in the inspection of various types of plastic products have been resolved, achieving efficient and accurate defect detection of plastic products.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENZHEN HEMEI RISHENG TECH CO LTD
- Filing Date
- 2026-03-30
- Publication Date
- 2026-05-29
AI Technical Summary
Existing plastic product testing equipment cannot meet the testing needs of multiple categories, resulting in insufficient testing accuracy and poor versatility. In particular, when testing high-gloss mirror surfaces, frosted parts, and deep cavity parts, the imaging contrast is insufficient or there are blind spots.
It adopts an adaptive supplementary lighting mechanism and an active switching mechanism. The main controller controls the adjustment of the supplementary lighting angle and the switching of the diffuser plate station. Combined with diffusers with different optical properties, it achieves adaptive matching between the light field and the characteristics of the plastic product to be tested, thereby improving the accuracy and versatility of the test.
It achieves clear imaging of defects in different types of plastic products, simplifies the inspection process, improves inspection efficiency and accuracy, avoids uneven lighting and blind spots, and ensures the stability and adaptability of the inspection.
Smart Images
Figure CN122109129A_ABST
Abstract
Description
Technical Field
[0001] This application provides a device for detecting defects in finished plastic products, specifically relating to the field of plastic product testing technology. Background Technology
[0002] Visual inspection has become the mainstream automated inspection method for detecting appearance defects in injection-molded plastic products (such as missing material, burrs, shrinkage marks, cracks, color difference, and flash). The lighting system is the core component of visual inspection; the uniformity of illumination, the angle of illumination, and the light scattering characteristics directly determine the clarity of defect imaging and the accuracy of detection. Detecting appearance defects in injection-molded plastic products is a crucial step in ensuring the yield rate of plastic products leaving the factory and is widely used in the production of various plastic products, including consumer electronics, automotive parts, and daily-use plastic parts.
[0003] In the existing technology, Chinese invention patent with publication number CN114813757B discloses a full-angle appearance inspection device for plastic products. This device adopts a fixed-angle ring LED supplementary lighting structure with a single-specification uniform light diffusion plate design. The supplementary lighting angle cannot be adjusted according to the characteristics of the plastic parts, and the diffusion plate does not have an adaptation and switching function. When inspecting high-gloss mirror plastic parts, it is easy to produce reflection and overexposure. When inspecting frosted plastic parts, the imaging contrast of small defects is insufficient. For plastic parts with deep cavities and ribs, it will also form blind spots and shadows. It is difficult to adapt to the high-precision inspection needs of multiple types of plastic products. The equipment's versatility and inspection accuracy cannot meet the actual use requirements of mass production. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this application provides a device for detecting defects in finished plastic products, which can effectively solve the problem mentioned in the background technology that "the light field for plastic detection in existing detection devices is difficult to adapt to multiple categories and has insufficient accuracy".
[0005] To achieve the above objectives, this application provides the following technical solution: This application discloses a defect detection device for finished plastic products, including a main unit, an X-axis linear module on the main unit, a support plate for placing the plastic product to be tested on the X-axis linear module, a detection box fixedly installed on the top surface of the main unit, a Z-axis linear module inside the detection box, an L-shaped cantilever connected to the movable output end of the Z-axis linear module, and an AOI camera installed on the L-shaped cantilever. It is also equipped with a main controller, an image module, and a display module. The main controller is electrically connected to the X-axis linear module, the Z-axis linear module, and the AOI camera. The image module is electrically connected to the AOI camera and the main controller. The display module is electrically connected to the image module. An adaptive lighting mechanism is located below the AOI camera, and an active switching mechanism is located below the adaptive lighting mechanism. The main controller is also electrically connected to the adaptive lighting mechanism and the active switching mechanism respectively. The main controller receives the detection signal output by the image module and controls the adjustment of the lighting angle of the adaptive lighting mechanism and the switching of the optical diffusion component position of the active switching mechanism in conjunction with the detection signal.
[0006] In summary, the technical solution provided in this application has at least one of the following advantages compared with the prior art: This plastic product defect detection device, by setting an adaptive supplementary lighting mechanism and an active switching mechanism below the AOI camera, allows the main controller to receive the detection signal output by the image module and control the adjustment of the supplementary lighting angle of the adaptive supplementary lighting mechanism and the switching of the diffuser plate position of the active switching mechanism. This solves the problems of fixed supplementary lighting angle in the existing technology, which cannot adapt to the detection needs of different plastic products, resulting in problems such as reflection, shadows and insufficient imaging contrast during detection. It achieves adaptive matching between the detection light field and the characteristics of the plastic product to be tested, improving the device's versatility and core detection accuracy for detecting defects in different types of plastic products. Meanwhile, it is equipped with four different optical diffuser plates, which can be switched according to the surface and structural characteristics of the plastic products to be tested. The standard uniform light diffuser plate is suitable for conventional parts, the low reflectivity soft light diffuser plate suppresses the reflection of high-gloss parts, the high scattering angle diffuser plate eliminates the shadows of deep cavity parts, and the microstructure prism uniform light plate highlights the tiny defects of frosted parts. This allows the defect features of different types of plastic products to be clearly imaged, achieving full-scene detection adaptation. There is no need to manually replace optical components, which greatly simplifies the detection operation process. When the LED lamp body of the adaptive supplementary lighting mechanism adjusts the supplementary lighting angle, the main controller will synchronously adjust its output brightness to achieve angle and brightness coupling compensation, ensuring that the light intensity of the detection station is always stable, avoiding excessive or insufficient light due to angle changes. In addition, the overall illumination range of the LED lamp body is smaller than the effective light transmission range of the diffuser plate. The light always illuminates the workpiece after being optically modulated by the diffuser plate, eliminating imaging interference caused by direct light, and further improving the uniformity of imaging and the clarity of defect identification. The main controller can realize the orderly linkage of feeding, focusing, supplementary lighting adjustment and diffuser switching. The completion signal of the previous action of each mechanism is used as the trigger signal of the next action, which effectively avoids the interference between the actions of the mechanisms, allowing the detection process to proceed in an orderly manner and realizing the automated detection of defects in plastic products. At the same time, the closed detection chamber isolates external stray light and dust, and the wear-resistant design of the moving parts ensures positioning accuracy, which not only improves detection efficiency, but also ensures the structural and detection stability of the device for long-term use. The LED lamp body, employing an array-style LED bead layout, combined with an aluminum substrate and heat dissipation shell, effectively reduces light decay during LED operation, ensuring long-term stability of the supplementary lighting effect. Furthermore, the lamp body's weight is well-suited for the drive load of a micro servo motor, allowing for smooth rotation and adjustment without jamming, guaranteeing precise adjustment of the supplementary lighting angle. The soft silicone flexible skirt of the support ring allows for flexible contact with the LED lamp body and also prevents dust from contaminating the diffuser plate, ensuring the performance and lifespan of the optical components. Attached Figure Description
[0007] Figure 1 This is a front-view stereoscopic structural diagram of this application; Figure 2 This is a partial three-dimensional structural diagram of the relevant components in the cross-section state of the detection box in this application; Figure 3 This is a partial three-dimensional structural diagram of the relevant components in the adaptive illumination mechanism and the active switching mechanism in this application; Figure 4 This is a partial three-dimensional structural diagram of the relevant components in the adaptive lighting mechanism of this application; Figure 5 This is a partial bottom-view perspective view of the relevant components of the adaptive lighting mechanism in this application; Figure 6 This is a partially exploded three-dimensional structural view of the relevant components of the adaptive lighting mechanism in this application; Figure 7 This is a partially exploded three-dimensional structural view of the relevant components of the active switching mechanism in this application; Figure 8 This is a comparative schematic diagram of the adjustment angle of the active switching mechanism in this application; Figure 9 This is a partial three-dimensional structural diagram of the relevant components in the X-axis linear module and Z-axis linear module of this application.
[0008] The labels in the diagram represent: 1. Main unit; 11. X-axis linear module; 111. Servo telescopic cylinder; 112. Twin guide rail; 113. Slider; 12. Detection box; 13. Z-axis linear module; 131. Servo motor; 132. Guide slide; 133. Slide plate; 14. Bearing plate; 15. L-shaped cantilever; 16. AOI camera; 2. Adaptive lighting mechanism; 21. Positioning ring; 22. LED lamp body; 221. First connecting piece; 222. Lateral shaft; 23. Miniature servo motor; 231. Second connecting piece; 232. Coupling; 3. Active switching mechanism; 31. Stepper drive motor; 32. Switching disc; 33. Support ring; 331. Flexible skirt; 34. Diffuser plate; 4. Main controller; 5. Image module; 6. Display module. Detailed Implementation
[0009] The present application will be further described below with reference to embodiments.
[0010] As a first embodiment of this application: Reference Appendix Figures 1 to 9 As shown, a defect detection device for finished plastic products includes a main unit 1, an X-axis linear module 11 on the main unit 1, a support plate 14 for placing the plastic product to be tested on the X-axis linear module 11, and a detection chamber 12 fixedly installed on the top surface of the main unit 1 by bolts. The detection chamber 12 adopts a closed sheet metal structure, which can effectively isolate the interference of external stray light and dust on the detection process and ensure the stability of the detection environment.
[0011] Specifically, inside the detection chamber 12, a Z-axis linear module 13 is vertically installed. An L-shaped cantilever 15 is bolted to the moving output end of the Z-axis linear module 13. An AOI camera 16 is installed at the end of the L-shaped cantilever 15 away from the Z-axis linear module 13. The lens of the AOI camera 16 is vertically downward, and the area of the bearing plate 14 directly below its lens axis is the detection station. The device is also equipped with a main controller 4, an image module 5 and a display module 6. The main controller 4 is electrically connected to the X-axis linear module 11, the Z-axis linear module 13 and the AOI camera 16 respectively. The image module 5 is electrically connected to the AOI camera 16 and the main controller 4 respectively. The display module 6 is electrically connected to the image module 5. Specifically, the X-axis linear module 11 includes a servo telescopic cylinder 111, two twin guide rails 112, and a slider 113. The servo telescopic cylinder 111 is fixed to the top surface of the main unit 1 by a mounting base. The two twin guide rails 112 are arranged parallel to each other on both sides of the servo telescopic cylinder 111 and are fixed to the top surface of the main unit 1 by bolts. The slider 113 slides with the twin guide rails 112. Wear-resistant self-lubricating pads are embedded at the mating surfaces of the slider 113 and the twin guide rails 112 to avoid wear of the guide rails caused by long-term reciprocating sliding and to ensure the motion positioning accuracy of the X-axis linear module 11. The output end of the servo telescopic cylinder 111 is connected to the slider 113 for transmission. The bottom of the support plate 14 is fixed to the top surface of the slider 113 by bolts. The upper surface of the support plate 14 is provided with an anti-slip buffer layer to prevent the plastic product to be tested from slipping during the feeding process and to avoid scratches on the workpiece surface caused by hard contact.
[0012] The Z-axis linear module 13 includes a servo motor 131, a guide slide 132, and a slide plate 133. The guide slide 132 is vertically fixed to the inner wall of the detection box 12 by a bracket. The servo motor 131 is fixed to the upper end of the guide slide 132 by a mounting base and its output end is connected to the guide slide 132 for transmission. The slide plate 133 slides with the guide slide 132. One end of the L-shaped cantilever 15 is welded and fixed to the slide plate 133. The AOI camera 16 is fixed to the other end of the L-shaped cantilever 15 by an adjustment bracket. The adjustment bracket can realize the small angle fine adjustment of the AOI camera 16 to ensure that the lens axis is vertically aligned with the detection station.
[0013] As a clear distinction from existing technologies, the AOI camera 16 is equipped with an adaptive lighting mechanism 2 below it, and an active switching mechanism 3 is also equipped with an adaptive lighting mechanism 2 below it. The main controller 4 is also electrically connected to the adaptive lighting mechanism 2 and the active switching mechanism 3 respectively. The main controller 4 receives the detection signal output by the image module 5, and controls the adjustment of the lighting angle of the adaptive lighting mechanism 2 and the switching of the optical diffusion component position of the active switching mechanism 3 in conjunction with the detection signal.
[0014] Specifically, the adaptive lighting mechanism 2 includes a positioning ring 21, LED lamp bodies 22, and a micro servo motor 23. The positioning ring 21 is fixed to the lower end of the AOI camera 16 by a snap-fit and is coaxial with the lens. The positioning ring 21 is made of lightweight aluminum alloy, which combines structural rigidity and lightweight requirements to avoid excessive impact on the motion load of the Z-axis linear module 13. Four LED lamp bodies 22 are arranged in a ring array below the positioning ring 21. In a preferred embodiment, the LED lamp bodies 22 adopt an array-type LED lighting module for industrial vision inspection. Each lamp body integrates 16 SMD2835 pure white LED beads arranged in a linear array. The color temperature of the lamp beads is 6000K and the color rendering index is ≥85, ensuring the imaging reproduction of details of defects in plastic products. The LED lamp bodies 22 use an aluminum-based copper-clad laminate as the lamp bead substrate, combined with a lightweight aluminum alloy heat dissipation shell, effectively reducing the workload of the lamp beads. The operating temperature is controlled to prevent light decay from affecting the supplementary lighting effect; the weight of a single lamp body is 40g, which is compatible with the drive load of the micro servo motor 23. The two ends of the lamp body have reserved connection holes. After being fixedly connected to the side shaft 222, it can rotate smoothly with the drive of the micro servo motor 23 without structural jamming; the LED lamp body 22 is powered by DC24V constant current and is connected to an external power supply through the terminal on its top; it supports 0-100% PWM brightness adjustment and can be linked with the control signal of the main controller 4 to realize the coupling compensation of the supplementary lighting angle and the output brightness.
[0015] Specifically, each LED lamp body 22 is rotatably connected to the first connecting piece 221 at the bottom of the positioning ring body 21 via a lateral shaft 222 on both sides. Each LED lamp body 22 is provided with a corresponding micro servo motor 23 on its side. The micro servo motor 23 is fixed to the outer circumference of the positioning ring body 21 via a second connecting piece 231. The output shaft of the micro servo motor 23 is connected to the lateral shaft 222 of the corresponding LED lamp body 22 via a coupling 232. The coupling 232 is made of elastic rubber material, which can compensate for the coaxiality deviation between the output shaft of the micro servo motor 23 and the lateral shaft 222, ensuring the stability of power transmission and avoiding shaft wear caused by rigid connection. The micro servo motor 23 drives the LED lamp body 22 to rotate and adjust the supplementary lighting angle.
[0016] Furthermore, the active switching mechanism 3 includes a stepper drive motor 31, a switching disk 32, a support ring 33, and a diffuser plate 34. The stepper drive motor 31 is fixed to the inside of the L-shaped cantilever 15 by a mounting bracket. The output shaft of the stepper drive motor 31 is vertically downward and is fixed to the switching disk 32 by a key connection. The key connection can ensure the circumferential positioning accuracy of the stepper drive motor 31 and the switching disk 32, and avoid station offset during the diffusion plate switching process. The switching disc 32 has four through holes arranged in a ring array. Each through hole is fixedly installed with a support ring 33 by interference fit. A diffuser plate 34 is fixedly embedded in the inner ring of the support ring 33. Each support ring 33 has a flexible skirt 331 made of soft silicone material on its top. The top surface of the flexible skirt 331 is in flexible contact with the bottom of the LED lamp body 22. Its function is not only to realize the flexible contact limit between the LED lamp body 22 and the support ring 33, but also to effectively prevent dust in the detection process from entering the gap between the support ring 33 and the diffuser plate 34, and to prevent the light-transmitting surface of the diffuser plate 34 from being contaminated and affecting the supplementary lighting effect.
[0017] As a second embodiment of this application: Reference Appendix Figure 7 , Figure 8As shown, the aforementioned plastic product defect detection device includes four diffuser plates 34: a standard uniform light diffuser plate, a low-reflectivity soft light diffuser plate, a high scattering angle diffuser plate, and a microstructure prism uniform light diffuser plate. Specifically, the standard uniform light diffuser plate has a medium scattering angle and basic uniform light characteristics, with no obvious focusing or scattering effect, making it suitable for detecting plastic products with conventional flat surfaces and no special optical characteristics; it serves as the basic suitable diffuser plate for detection. The low-reflectivity soft light diffuser plate has weak scattering and matte transmission characteristics, effectively suppressing specular high-gloss reflection of light, making it suitable for detecting high-gloss and mirror-smooth plastic products, avoiding the need for workpiece... Surface reflections can cause overexposure in AOI camera images, ensuring clear capture of defect details; the high scattering angle diffuser plate has ultra-wide scattering characteristics, enabling omnidirectional light diffusion with strong penetration, suitable for the inspection of plastic products with complex structures such as deep cavities, grooves, and ribs, effectively eliminating shadows in the dead corners of the workpiece structure and ensuring no blind spots in the inspection; the microstructure prism light-diffusing plate has directional light-diffusing characteristics, which can enhance the contrast of the surface texture of plastic products, suitable for the inspection of frosted and matte plastic products, clearly highlighting small defects such as shrinkage marks, burrs, and fine lines on the workpiece surface, improving the detection rate of small defects; In the initial state of the device, the standard uniform light diffusion plate is positioned directly below the lens of the AOI camera 16. The effective light transmission coverage of a single diffusion plate 34 is greater than the overall illumination range of the four LED lamp bodies 22. During the rotation of the LED lamp body 22 to adjust the supplementary light angle, the emitted light always illuminates the effective light transmission area of the diffusion plate 34. This structural design ensures that the emitted light of the LED lamp body 22 can be optically modulated by the diffusion plate 34 throughout the entire adjustment angle range, avoiding the problems of reflection or uneven illumination caused by direct light hitting the workpiece under test.
[0018] The micro servo motor 23 drives the LED lamp body 22 to rotate at an angle. When the main controller 4 drives the LED lamp body 22 to adjust the supplementary lighting angle, it synchronously adjusts the output brightness of the LED lamp body 22 to achieve angle and brightness coupling compensation. Preferably, the main controller 4 has a built-in angle and brightness coupling compensation algorithm, which can automatically match the corresponding brightness adjustment parameters according to the actual rotation angle of the LED lamp body 22 to ensure that the illumination intensity of the workpiece detection station is always within a stable range and avoid excessive or insufficient illumination caused by angle changes.
[0019] Specifically, the main controller 4 can synchronously control the feeding action of the X-axis linear module 11, the focusing action of the Z-axis linear module 13, the light adjustment action of the adaptive supplementary lighting mechanism 2, and the diffusion plate switching action of the active switching mechanism 3 according to the detection signal of the image module 5, so as to realize the full-process time-series linkage. The main controller 4 has a built-in time-series control program to precisely control the action sequence and action interval of each mechanism. The action completion signal of the previous mechanism is the action trigger signal of the next mechanism, avoiding interference between the actions of each mechanism, ensuring the orderliness of the detection process and the detection efficiency. At the same time, the image module 5 can transmit the image information collected by the AOI camera 16 to the display module 6 in real time for display, so that the operator can observe the detection process and the imaging status of the workpiece in real time, and can intervene in time in case of detection abnormalities.
[0020] The complete working and usage principle of the above embodiments is as follows: The plastic product to be tested is placed on the anti-slip buffer layer of the support plate 14. The main controller 4 sends a control signal to the X-axis linear module 11. The servo telescopic cylinder 111 drives the slider 113 to slide along the twin guide rail 112, which moves the support plate 14 and the plastic product to be tested to the testing station. After the limit switch of the X-axis linear module 11 detects the feeding position signal, it feeds the signal back to the main controller 4. Only then does the main controller 4 start the subsequent testing process, realizing the timing linkage between the feeding action and the testing action. After receiving the arrival signal, the main controller 4 sends a control signal to the Z-axis linear module 13. The servo motor 131 drives the guide slide 132 to move the slide plate 133 up and down. The height of the AOI camera 16 is adjusted to the focus position by the L-shaped cantilever 15. After focusing is completed, the Z-axis linear module 13 sends a focus completion signal back to the main controller 4.
[0021] After receiving the focusing completion signal, the main controller 4 starts the AOI camera 16 to acquire the initial image of the plastic product to be tested. After the initial image is transmitted to the image module 5, the image module 5 performs feature extraction and analysis on the initial image, identifies the surface optical properties of the plastic product to be tested and the reflection, shadow and other states of the initial image, generates the corresponding detection signal and transmits it to the main controller 4. The main controller 4 sends a control signal to the active switching mechanism 3 based on the detection signal. The stepper drive motor 31 drives the switching disk 32 to rotate, switching the diffuser plate 34, which matches the surface characteristics of the plastic product to be tested, into the optical path directly below the lens of the AOI camera 16. The switching disk 32 is equipped with a station positioning sensor. After the diffuser plate is switched into position, the sensor will feed back the position signal to the main controller 4 to ensure the switching positioning accuracy of the diffuser plate.
[0022] After the diffuser plate is switched into position, the main controller 4 sends a control signal to the adaptive lighting mechanism 2 based on the detection signal. The micro servo motor 23 drives the corresponding LED lamp body 22 to rotate around the lateral axis 222, adjusting the lighting angle of the LED lamp body 22. At the same time, the main controller 4 adjusts the output brightness of the LED lamp body 22 synchronously according to the angle and brightness coupling compensation algorithm, realizing the coordinated adjustment of the lighting angle and brightness. After the lighting adjustment is completed, the main controller 4 starts the AOI camera 16 to perform formal image acquisition. After the acquired image is processed and analyzed by the image module 5, the defect detection of the plastic product under test is completed. The detection results and workpiece images are transmitted to the display module 6 in real time for display. At the same time, the image module 5 feeds back the detection results to the main controller 4.
[0023] After the inspection is completed, the main controller 4 sends a control signal to the X-axis linear module 11, which drives the carrier plate 14 to send the inspected plastic product away from the inspection station. At the same time, the adaptive supplementary lighting mechanism 2 and the active switching mechanism 3 return to their initial state, waiting for the next plastic product to be inspected. The entire inspection process is fully automated and time-linked, requiring no manual intervention, which effectively improves the inspection efficiency. Meanwhile, the coordinated cooperation of each mechanism ensures the inspection accuracy and can be adapted to the defect inspection of plastic products with different surface characteristics.
[0024] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application. It should be understood that in this application, the rotating, sliding, meshing, belt-driven and other moving parts are well lubricated and not prone to slipping or wear, and each of them is provided with a corresponding protective shell. However, in the accompanying drawings of this application, the connection state of each moving part is not shown. It should also be understood that each part in this application is made of metal or plastic material with adaptable strength in the relevant field to ensure that its structural rigidity meets the actual requirements.
Claims
1. A device for detecting defects in finished plastic products, comprising a main unit (1), an X-axis linear module (11) provided on the main unit (1), a support plate (14) for placing the plastic product to be tested provided on the X-axis linear module (11), a detection box (12) fixedly installed on the top surface of the main unit (1), a Z-axis linear module (13) provided inside the detection box (12), an L-shaped cantilever (15) connected to the movable output end of the Z-axis linear module (13), and an AOI camera (16) installed on the L-shaped cantilever (15). It is also equipped with a main controller (4), an image module (5), and a display module (6). The main controller (4) is electrically connected to the X-axis linear module (11), the Z-axis linear module (13), and the AOI camera (16), respectively. The image module (5) is electrically connected to the AOI camera (16) and the main controller (4), respectively. The display module (6) is electrically connected to the image module (5). The feature is that: An adaptive lighting mechanism (2) is provided below the AOI camera (16), and an active switching mechanism (3) is provided below the adaptive lighting mechanism (2). The main controller (4) is also electrically connected to the adaptive lighting mechanism (2) and the active switching mechanism (3) respectively. The main controller (4) receives the detection signal output by the image module (5) and controls the adjustment of the lighting angle of the adaptive lighting mechanism (2) and the switching of the optical diffusion component position of the active switching mechanism (3) according to the detection signal.
2. The defect detection device for finished plastic products according to claim 1, characterized in that, The X-axis linear module (11) includes a servo telescopic cylinder (111), two twin guide rails (112) and a slider (113). The servo telescopic cylinder (111) is fixedly installed on the top surface of the host (1). The two twin guide rails (112) are arranged on both sides of the servo telescopic cylinder (111) and fixed to the top surface of the host (1). The slider (113) slides with the twin guide rails (112). The output end of the servo telescopic cylinder (111) is connected to the slider (113) for transmission. The bottom of the support plate (14) is fixedly connected to the top surface of the slider (113).
3. The defect detection device for finished plastic products according to claim 1, characterized in that, The adaptive lighting mechanism (2) includes a positioning ring (21), an LED lamp body (22), and a micro servo motor (23). The positioning ring (21) is fixed to the lower end of the AOI camera (16) and is coaxial with the lens. Four LED lamp bodies (22) are arranged in a ring array below the positioning ring (21). Both sides of each LED lamp body (22) are rotatably connected to the first connector (221) at the bottom of the positioning ring (21) through a lateral shaft (222). A micro servo motor (23) is correspondingly set on the side of each LED lamp body (22). The micro servo motor (23) is fixed to the outer circumference of the positioning ring (21) through a second connector (231). The output shaft of the micro servo motor (23) is connected to the lateral shaft (222) of the corresponding LED lamp body (22) through a coupling (232). The micro servo motor (23) drives the LED lamp body (22) to rotate and adjust the lighting angle.
4. The defect detection device for finished plastic products according to claim 3, characterized in that, The micro servo motor (23) drives the LED lamp body (22) to rotate within the range of 0-20 degrees. When the main controller (4) drives the LED lamp body (22) to adjust the supplementary light angle, it synchronously adjusts the output brightness of the LED lamp body (22) to achieve angle-brightness coupling compensation.
5. The defect detection device for finished plastic products according to claim 1, characterized in that, The active switching mechanism (3) includes a stepper drive motor (31), a switching disk (32), a support ring (33), and a diffuser plate (34). The stepper drive motor (31) is fixed inside the L-shaped cantilever (15). The output shaft of the stepper drive motor (31) is vertically downward and fixedly connected to the switching disk (32). The switching disk (32) has four through holes arranged in a ring array. The support ring (33) is fixedly installed in each through hole. The diffuser plate (34) is fixedly embedded in the inner ring of the support ring (33).
6. The defect detection device for finished plastic products according to claim 5, characterized in that, The four light diffusion plates (34) are a standard light diffusion plate, a low reflectivity soft light diffusion plate, a high scattering angle diffuser plate, and a microstructure prism light diffusion plate. In the initial state of the device, the standard light diffusion plate corresponds to the position directly below the lens of the AOI camera (16).
7. The defect detection device for finished plastic products according to claim 5, characterized in that, The effective light transmission coverage of a single diffuser plate (34) is greater than the overall illumination range of four LED lamp bodies (22). During the process of rotating and adjusting the supplementary light angle of the LED lamp body (22), the emitted light always illuminates the effective light transmission area of the diffuser plate (34).
8. The defect detection device for finished plastic products according to claim 5, characterized in that, Each support ring (33) is provided with a flexible skirt (331) made of soft silicone material at the top, and the top surface of the flexible skirt (331) is in flexible contact with the bottom of the LED lamp body (22).
9. The defect detection device for finished plastic products according to claim 1, characterized in that, The Z-axis linear module (13) includes a servo motor (131), a guide slide (132) and a slide plate (133). The guide slide (132) is vertically fixed to the inner wall of the detection box (12). The servo motor (131) is fixed to the upper end of the guide slide (132) and its output end is connected to the guide slide (132) for transmission. The slide plate (133) is slidably engaged with the guide slide (132). One end of the L-shaped cantilever (15) is fixed to the slide plate (133). The AOI camera (16) is fixed to the other end of the L-shaped cantilever (15) and its lens is vertically facing the detection station above the support plate (14).
10. The defect detection device for finished plastic products according to claim 1, characterized in that, The main controller (4) can synchronously control the feeding action of the X-axis linear module (11), the focusing action of the Z-axis linear module (13), the light adjustment action of the adaptive light-filling mechanism (2), and the diffusion plate switching action of the active switching mechanism (3) according to the detection signal of the image module (5), so as to realize the full-process time-series linkage.