CCD (Charge Coupled Device) mistake-proof detection equipment for timing chain of engine cylinder body

Abstract

The invention relates to the technical field of industrial visual inspection, in particular to CCD (Charge Coupled Device) mistake-proof detection equipment for a timing chain of an engine cylinder block, which realizes the comprehensive detection of a contour, an internal structure and surface defects in one-time positioning by integrating a multi-mode light source system and an isolation detection environment. Meanwhile, the device has the functions of light source parameter self-correction and spectrum dynamic adjustment, and imaging conditions can be automatically optimized according to detection characteristics. The equipment solves the problems of environmental interference, incomplete feature extraction, frequent equipment maintenance and the like in traditional visual detection, and the detection reliability and the long-term working stability are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of industrial vision inspection technology, specifically to a CCD error-proofing inspection device for engine cylinder timing chain. Background Technology

[0002] In the field of intelligent engine manufacturing, the precise installation of the timing chain directly affects the overall performance and reliability of the engine. Currently, the industry widely adopts automated inspection solutions based on machine vision, but these devices still have significant limitations in practical applications. Their lighting systems often use fixed light sources, which cannot simultaneously meet the different optical requirements of contour recognition, internal structure inspection, and surface defect detection. When light shines on the complex structure of the engine block, protruding parts create shadows, and smooth surfaces generate interfering reflections. These optical interferences result in incomplete image features, severely affecting the accuracy of the inspection.

[0003] A more prominent problem is the lack of environmental adaptability in existing equipment. As the equipment continues to operate, the LED light source degrades, and dust accumulates on the lens and protective glass, all of which contribute to a gradual decline in image quality. Because it cannot perceive changes in its own condition, traditional equipment requires engineers to perform manual calibration and parameter adjustments periodically. This not only increases maintenance costs but may also lead to batch misjudgments between maintenance intervals.

[0004] Therefore, it is necessary to develop a CCD error-proofing detection device for engine cylinder block timing chain to solve the above problems. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] A CCD error-proofing detection device for engine cylinder block timing chain includes a chain conveyor belt, a movable boat disposed on the chain conveyor belt, a blocking device for blocking and positioning the movable boat, a lifting device for lifting the upper plate of the movable boat, and a CCD camera, further comprising: An isolation chamber is mounted above the lifting device via a lifting drive mechanism; the isolation chamber is equipped with a multimodal light source system and a micro-environment light sensor. The multimodal light source system includes a low-angle grazing light group, a diffuse light group, and a high-angle light group; The main control system is electrically connected to the lifting drive mechanism, the multimodal light source system, the micro-ambient light sensor, and the CCD camera, and is configured as follows: The isolation chamber is controlled to descend to create an isolation detection space; Based on a pre-stored light field scheme associated with specific detection features of the engine cylinder timing chain, the multi-modal light source system is driven to sequentially switch to different illumination modes; Under each lighting mode, the CCD camera is triggered to acquire a feature image; Multiple feature images collected are analyzed to complete error prevention detection.

[0007] Preferably, the low-angle sweeping light group is a strip LED light, which is arranged in a ring on the lower part of the inner wall of the isolation chamber. Its light emission direction forms an upward angle with the horizontal plane, and is used to generate a low-angle sweeping mode to enhance the contrast of the engine cylinder timing chain and sprocket edge contours.

[0008] Preferably, the diffused light group is a dome-shaped light source, including an LED array and a first diffuser plate covering the front of the LED array, for generating a uniform diffused light mode to uniformly illuminate the deep hole and recessed structure. The LED array is installed at the bottom of the dome, and the dome is located on one side of the isolation chamber.

[0009] Preferably, the multimodal light source system further includes a supplementary lighting structure, which includes a reflection channel installed at the center of the first diffuser plate, a second diffuser plate fixedly connected to the end of the reflection channel, and a CCD camera fixedly connected to the center of the second diffuser plate.

[0010] Preferably, the high-angle light group is a ring-shaped LED light, coaxially mounted around the lens of the CCD camera, with its light emission direction forming an angle between 30° and 60° with the optical axis of the CCD camera, used to generate a vertical high-angle mode to detect surface flatness.

[0011] Preferably, the main control system is configured to switch illumination modes in the following order: first, start the low-angle grazing light group for contour detection, then switch to the diffuse light group for deep hole and integrity detection, and finally switch to the high-angle light group for surface defect detection.

[0012] Preferably, the main control system is further configured to: after each detection, optimize the brightness parameters of the corresponding light group in the pre-stored light field scheme based on the sharpness index of the multiple feature images acquired this time, specifically through the following steps: Image quality analysis: For the feature images acquired under each illumination mode, within their predefined region of interest (ROI), the sum of squared gradient magnitudes is calculated to quantify their sharpness evaluation value; Performance evaluation: The calculated sharpness evaluation value is compared with the pre-stored target sharpness threshold for this modality; Parameter adjustment: If the sharpness evaluation value is lower than the target sharpness threshold for N consecutive detection cycles, the brightness parameter of the corresponding lamp group in the light field scheme is enhanced according to the preset adjustment step size; where N is an integer greater than 1. Solution Update: The successfully optimized brightness parameters are updated into the light field scheme for subsequent testing of the timing chain of the same engine block.

[0013] Preferably, the micro-ambient light sensor is a spectral sensor; the main control system is further configured to: dynamically adjust the color temperature of at least one lamp group in the multimodal light source system based on the spectral distribution of the isolation chamber detected by the micro-ambient light sensor and in combination with pre-stored reflectance spectral characteristics of different materials on the workpiece being tested, so as to optimize the imaging contrast between the target and the background for specific target detection features. Specifically, the main control system is configured to enhance the brightness of the plastic material feature in the CCD camera image by adjusting the color temperature of the lamp group to a lower color temperature when the target detection feature is made of plastic and its background is made of metal.

[0014] Preferably, the inner wall of the isolation chamber is coated with a light-absorbing coating.

[0015] Preferably, during fusion analysis, the main control system is configured to extract the image regions most relevant to the specific detection features from feature images acquired under different lighting modalities, and then perform splicing or logical synthesis to generate the final detection result.

[0016] The beneficial effects of this invention are: This invention improves detection efficiency and significantly reduces the false positive rate by combining a multimodal light source system and control scheme. The equipment has self-adjusting capabilities, optimizing operating parameters based on actual imaging quality, effectively overcoming the performance degradation of traditional equipment due to long-term use and reducing maintenance needs. Simultaneously, the spectral adjustment function intelligently enhances the imaging differences of components made of different materials, solving the problem of insufficient contrast in visual inspection of complex workpieces, and overall improving the automation level and quality stability of the production line. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] in: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 A schematic diagram of the engine block timing chain and chain conveyor belt structure; Figure 3 This is a schematic diagram of the chain conveyor belt, lifting device, and blocking device. Figure 4 A schematic diagram of the isolation chamber, lifting drive mechanism, and chain conveyor belt structure; Figure 5 This is a schematic diagram of the internal structure of the isolation chamber; Figure 6 This is a schematic diagram of a multimodal light source system. Figure 7 This is a schematic diagram of the diffused light assembly structure; Figure 8 A schematic diagram of the diffused light assembly and supplementary lighting structure; Figure 9 A schematic diagram of the optical path of the supplementary lighting structure; In the picture: 11. Chain conveyor belt; 12. Carrier plate; 13. Moving boat; 14. Lifting device; 15. Blocking device; 2. Isolation chamber; 3. Lifting drive mechanism; 31. Track; 32. Sliding trolley; 4. Multimodal light source system; 41. Low-angle grazing light group; 42. High-angle light group; 43. Diffuse light group; 431. LED array; 432. Dome; 433. No. 1 diffuser plate; 44. Supplemental lighting structure; 441. Reflection channel; 442. No. 2 diffuser plate; 5. CCD camera; 6. Main control system; 7. Micro ambient light sensor; 99. Engine cylinder block timing chain. Detailed Implementation

[0019] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0020] like Figures 1-9 As shown: Example

[0021] A CCD error-proofing detection device for engine cylinder block timing chain includes a chain conveyor belt 11, a movable boat 13 disposed on the chain conveyor belt 11, a blocking device 15 for blocking and positioning the movable boat 13, a lifting device 14 for lifting the upper plate 12 of the movable boat 13, and a CCD camera 5, and further includes: The isolation chamber 2 is installed above the lifting device 14 via a lifting drive mechanism 3; the isolation chamber 2 is equipped with a multimodal light source system 4 and a micro-ambient light sensor 7. The multimodal light source system 4 includes a low-angle sweeping light group 41, a diffused light group 43, and a high-angle light group 42; The main control system 6 is electrically connected to the lifting drive mechanism 3, the multimodal light source system 4, the micro-ambient light sensor 7, and the CCD camera 5, and is configured as follows: The isolation chamber 2 is controlled to descend to form an isolation detection space; Based on a pre-stored light field scheme associated with specific detection features of the engine cylinder timing chain 99, the multi-modal light source system 4 is driven to sequentially switch to different illumination modes; Under each lighting mode, the CCD camera 5 is triggered to acquire a feature image; Multiple feature images collected are analyzed to complete error prevention detection.

[0022] The chain conveyor belt 11 transports the mobile boat 13 carrying the engine block timing chain 99 to the inspection station. The blocking device 15 is raised (the blocking device 15 is existing technology and will not be described in detail here) to stop and position the mobile boat 13. This positioning process ensures that each engine block timing chain 99 is in the same inspection position. The lifting device 14 (which is existing technology and will not be described in detail here) is activated, lifting the carrier plate 12 on the mobile boat 13 to a predetermined height. Simultaneously, the sliding carriage 32 in the lifting drive mechanism 3 drives the isolation chamber 2 down along the track 31, forming an isolated detection space with the carrier plate 12. This effectively isolates the chamber from external ambient light interference, creating a stable optical environment for subsequent image acquisition. The main control system 6 controls the multimodal light source system 4 to sequentially switch between different illumination modes according to a pre-stored light field scheme. Under each mode, the CCD camera 5 acquires the corresponding feature image. This multimodal time-division imaging method can obtain the optimal illumination effect for different detection features; The main control system 6 fuses and analyzes multiple feature images to comprehensively determine the installation status of the engine block timing chain 99. By complementing information from multiple images, the accuracy and reliability of the detection are improved. After the test is completed, the isolation chamber 2 is raised first, followed by the lifting device 14 being lowered, and the mobile boat 13 is lowered back onto the chain conveyor belt 11, flowing to the next process according to the test results. Example

[0023] Specifically, the low-angle sweeping light group 41 is a strip LED light, which is arranged in a ring on the lower part of the inner wall of the isolation chamber 2. Its light emission direction forms an upward angle with the horizontal plane, and is used to generate a low-angle sweeping mode to enhance the contrast between the engine cylinder timing chain 99 and the edge contour of the sprocket.

[0024] The diffused light group 43 is a dome-shaped light source, including an LED array 431 and a first diffuser plate 433 covering the front of the LED array 431, used to generate a uniform diffused light mode to uniformly illuminate the deep hole and recessed structure. The LED array 431 is installed at the bottom of the dome 432, and the dome 432 is located on one side of the isolation chamber 2.

[0025] The multimodal light source system 4 also includes a supplementary light structure 44, which includes a reflection channel 441 installed at the center of the first diffuser plate 433. A second diffuser plate 442 is fixedly connected to the end of the reflection channel 441, and the CCD camera 5 is fixedly connected to the center of the second diffuser plate 442.

[0026] The high-angle light group 42 is a ring-shaped LED light, coaxially mounted around the lens of the CCD camera 5. Its light emission direction is at an angle of 30° to 60° with the optical axis of the CCD camera 5, and is used to generate a vertical high-angle mode to detect surface flatness.

[0027] The low-angle grazing light group 41 consists of multiple strip LED lights arranged in a ring array on the lower part of the inner wall of the isolation chamber 2, with its light emission direction forming an upward angle of 5° to 20° with the horizontal plane.

[0028] Advantages over existing technologies: Traditional forward or vertical lighting struggles to highlight the three-dimensional morphological features of the timing chain 99 and sprocket meshing profile in processing engine block timing chain meshing contours. The lighting method in this solution illuminates the vertical surfaces of each tooth and link of the engine block timing chain 99, while the horizontal surfaces remain in shadow, creating a distinct "black and white" contour effect in the image captured by the CCD camera 5. This allows the image processing algorithm to identify the meshing state of the engine block timing chain 99, whether there are skipped teeth or slack, improving the accuracy of contour feature recognition and solving the misjudgment problem caused by insufficient contrast in existing technologies.

[0029] The diffused light group 43 adopts a dome-shaped light source structure. Its LED array 431 is arranged on the base of the dome 432. The emitted light is reflected in the cavity of the dome 432 with a reflective coating, forming a uniform light mixture, and finally converted into a surface light source with highly uniform brightness through the first diffuser plate 433.

[0030] Advantages over existing technologies: Traditional lighting, when inspecting components with deep holes or recesses (such as the 99 pin of the engine block timing chain), often produces unpredictable shadows due to insufficient light penetration, or creates interfering flares on smooth surfaces due to single-angle illumination. This solution's dome-shaped diffused light effectively fills in the shadows of holes, ensuring that the end of each 99 pin of the engine block timing chain is illuminated, facilitating inspection of its proper installation. Simultaneously, it converts specular reflection on the workpiece surface into diffuse reflection, eliminating localized overexposure and allowing the CCD camera 5 to capture a balanced image. This solves the problem of blind spots caused by shadows and reflections.

[0031] The high-angle light group 42 is a ring-shaped LED light, coaxially mounted around the lens of the CCD camera 5, with its light emission direction forming an angle of 30° to 60° with the camera's optical axis.

[0032] Advantages compared to existing technologies: Conventional lighting struggles to effectively highlight microscopic imperfections on a workpiece surface, such as scratches, dents, or processing defects. The directional lighting method in this solution causes specular reflection on smooth surfaces, with most light entering the camera to create a bright field. In areas with scratches, dents, or stains, the light is scattered, with only a small amount entering the camera, appearing as dark features in the image. This enhances the contrast between surface defects and the background, making defects readily apparent under ordinary lighting.

[0033] In the supplementary lighting structure 44, after the light is reflected in the cavity of the dome 432 with a reflective coating, part of the light source enters the reflection channel 441, and then enters the second diffuser plate 442 from the reflection channel 441, and is directed to illuminate the engine cylinder block timing chain 99 (e.g. Figure 9 (As shown), to supplement the light source blocked by the CCD camera 5. Example

[0034] Specifically, the main control system 6 is configured to switch illumination modes in the following order: first, the low-angle grazing light group 41 is activated to perform contour detection, then the diffuse light group 43 is switched to perform deep hole and integrity detection, and finally the high-angle light group 42 is switched to perform surface defect detection.

[0035] The main control system 6 is also configured to: after each detection, optimize the brightness parameters of the corresponding light group in the pre-stored light field scheme based on the sharpness index of the multiple feature images acquired this time, specifically through the following steps: Image quality analysis: For the feature images acquired under each illumination mode, within their predefined region of interest (ROI), the sum of squared gradient magnitudes is calculated to quantify their sharpness evaluation value; Performance evaluation: The calculated sharpness evaluation value is compared with the pre-stored target sharpness threshold for this modality; Parameter adjustment: If the sharpness evaluation value is lower than the target sharpness threshold for N consecutive detection cycles, the brightness parameter of the corresponding lamp group in the light field scheme is enhanced according to the preset adjustment step size; where N is an integer greater than 1. Solution Update: The successfully optimized brightness parameters are updated into the light field scheme for subsequent testing of the timing chain 99 of the same engine block.

[0036] The micro-ambient light sensor 7 is a spectral sensor; the main control system 6 is also configured to: dynamically adjust the color temperature of at least one lamp group in the multimodal light source system 4 according to the spectral distribution of the isolation chamber 2 detected by the micro-ambient light sensor 7, and in combination with the pre-stored reflectance spectral characteristics of different materials on the workpiece being tested, so as to optimize the imaging contrast between the target and the background for specific target detection features. Specifically, the main control system 6 is configured to enhance the brightness of the plastic material feature in the image of the CCD camera 5 by adjusting the color temperature of the lamp group to a lower color temperature when the target detection feature is made of plastic material and its background is made of metal material.

[0037] The main control system 6 is configured to execute the light source switching logic: first, start the low-angle sweeping light group 41 to perform contour detection, then switch to the diffuse light group 43 to perform deep hole and integrity detection, and finally enable the high-angle light group 42 to perform surface defect detection.

[0038] Advantages over existing technologies: Existing devices often employ a mode of simultaneously illuminating all light sources or randomly switching them, which leads to interference between light from different angles. For example, high-angle light can dilute the characteristic shadows formed by low-angle light, severely affecting the signal-to-noise ratio of image features. This solution's ordered switching scheme ensures that each illumination mode operates independently within the environment. This allows the CCD camera to capture the most representative feature images. This temporal physical isolation fundamentally eliminates crosstalk between different optical features, maximizing the detection efficiency of each mode and thus significantly improving the overall accuracy and reliability of the judgment.

[0039] After each detection, the main control system 6 initiates a self-calibration process. Within a predefined region of interest (ROI) of each feature image, the system quantifies its sharpness evaluation value by calculating the sum of squared gradient magnitudes. When the system detects that the sharpness evaluation value of a certain mode (such as the low-angle grazing mode) is lower than its preset target threshold for three consecutive times (N=3), it will enhance the brightness parameters of the corresponding lamp group in the light field scheme according to a fine adjustment step (such as 2% of brightness). The optimized parameters are immediately updated in the light field scheme for subsequent detection of all cylinders of the same model.

[0040] Advantages compared to existing technologies: Traditional equipment maintenance relies on manual calibration by engineers, resulting in delayed response and an inability to guarantee optimal parameter adjustments, leading to inefficient maintenance. This solution can detect image quality degradation and compensate for it before it affects the detection results. This closed-loop control based on image quality feedback can combat factors such as LED light decay and optical window contamination, ensuring the entire detection system maintains optimal operating conditions over a long period, reducing equipment maintenance costs and reliance on manual experience, and guaranteeing stable production quality. Example

[0041] Specifically, the inner wall of the isolation chamber 2 is coated with a light-absorbing coating.

[0042] During fusion analysis, the main control system 6 is configured to extract the image regions most relevant to the specific detection features from feature images acquired under different lighting modalities, and then perform splicing or logical synthesis to generate the final detection result.

[0043] This device integrates a spectral sensor as a micro-ambient light sensor 7. The main control system 6 not only monitors light intensity through it, but more importantly, analyzes the spectral distribution within the chamber. The system has a pre-stored database of reflectance spectral characteristics for different materials (such as black plastic, electroplated metal, and cast iron body). During the detection process, the main control system 6 can dynamically adjust the color temperature of specific lamp groups in the multimodal light source system 4.

[0044] Advantages compared to existing technologies: Existing devices use a fixed color temperature light source (such as 6500K white light), whose spectral composition is fixed. When inspecting a plastic tensioner, the grayscale difference between it and the metal background is not significant because the fixed spectrum cannot maximize the difference in reflectance between the two. When the goal is to highlight a black plastic tensioner from a metal background, the main control system 6 instructs the light source to adjust its color temperature towards a lower color temperature (such as 2700K-4500K, rich in red light). Since many dark plastics have higher reflectance to long-wavelength red light, while metals show little change, this operation increases the grayscale difference between the target feature and the background. This active spectral matching technology based on the optical properties of materials is equivalent to "customizing" the most suitable light for a specific inspection task, which can clearly "highlight" features with weak contrast, enhancing the system's ability to identify difficult defects.

[0045] The interior walls of ordinary chambers (such as white or aluminum surfaces) reflect a large amount of light. This stray light can create unpredictable secondary illumination on the workpiece surface, reducing the signal-to-noise ratio and contrast of the image.

[0046] The workflow is as follows: The engine block timing chain 99 and the cylinder block it is mounted on run on the chain conveyor belt 11 along the moving boat 13 to the inspection station. First, the blocking device 15 works to stop and position the moving boat 13. Then, the lifting device 14 rises, lifting the carrier plate 12 to the inspection height, while the lifting drive mechanism 3 drives the isolation chamber 2 to descend, forming an inspection environment together with the carrier plate 12, effectively isolating external light interference.

[0047] Inside the isolation chamber 2, the main control system 6 begins executing the multimodal inspection process. It first activates the low-angle sweeping light group 41, arranged in a ring around the lower part of the chamber wall. The light sweeps across the workpiece surface at a small angle, casting shadows on the meshing contours of the engine block timing chain 99 and sprockets. The CCD camera 5 then captures the first high-contrast contour image. Next, the main control system 6 switches to the dome-shaped diffused light group 43, whose uniform light fills the shadows of deep holes and depressions and eliminates reflections. The CCD camera 5 uses this to capture a second image that clearly shows the internal structure of the engine block timing chain 99 pins. Finally, the high-angle light group 42, coaxially mounted around the CCD camera 5, illuminates the workpiece surface at a specific angle, highlighting minute scratches or imperfections. The CCD camera 5 then completes the acquisition of the third surface quality image.

[0048] Throughout the process, the ambient light sensor 7 monitors the light field inside the cabin in real time, and the main control system 6 dynamically adjusts the color temperature of the light source to optimize the imaging contrast of components made of different materials (such as the plastic tensioner and the metal cylinder). After the inspection is completed, the main control system 6 performs fusion analysis on the three feature images to determine the installation result. At the same time, the system automatically performs correction and optimization based on the image sharpness index, adjusting the light source parameters to compensate for the performance degradation caused by long-term use.

[0049] Finally, the isolation chamber 2 is raised, the lifting device 14 is lowered, the mobile boat 13 falls back onto the chain conveyor belt 11, and flows to the next process according to the test results, completing the entire automated testing cycle.

[0050] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A CCD error-proofing detection device for engine cylinder block timing chain, comprising a chain conveyor belt (11), a movable boat (13) disposed on the chain conveyor belt (11), a blocking device (15) for blocking and positioning the movable boat (13), a lifting device (14) for lifting the upper plate (12) of the movable boat (13), and a CCD camera (5), characterized in that, Also includes: The isolation chamber (2) is installed above the lifting device (14) via a lifting drive mechanism (3); the isolation chamber (2) is equipped with a multimodal light source system (4) and a micro-environment light sensor (7). The multimodal light source system (4) includes a low-angle grazing light group (41), a diffuse light group (43), and a high-angle light group (42). The main control system (6) is electrically connected to the lifting drive mechanism (3), the multimodal light source system (4), the micro-ambient light sensor (7), and the CCD camera (5), and is configured as follows: The isolation chamber (2) is controlled to descend to form an isolation detection space; Based on a pre-stored light field scheme associated with specific detection characteristics of the engine cylinder timing chain (99), the multi-modal light source system (4) is driven to sequentially switch to different illumination modes; Under each illumination mode, the CCD camera (5) is triggered to acquire a feature image; Multiple feature images collected are analyzed to complete error prevention detection.

2. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The low-angle sweeping light group (41) is a strip LED light, which is arranged in a ring on the lower part of the inner wall of the isolation chamber (2). Its light emission direction forms an upward angle with the horizontal plane, and is used to generate a low-angle sweeping mode to enhance the contrast between the engine cylinder timing chain (99) and the sprocket edge contour.

3. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The diffused light group (43) is a dome-shaped light source, including an LED array (431) and a first diffused plate (433) covering the front of the LED array (431), which is used to generate a uniform diffused light mode to uniformly illuminate the deep hole and the recessed structure. The LED array (431) is installed at the bottom of the dome (432), and the dome (432) is located on one side of the isolation chamber (2).

4. The engine cylinder block timing chain CCD error prevention detection device according to claim 3, characterized in that, The multimodal light source system (4) further includes a supplementary light structure (44), which includes a reflection channel (441) installed at the center of the first diffuser plate (433), and a second diffuser plate (442) is fixedly connected to the end of the reflection channel (441), and the CCD camera (5) is fixedly connected to the center of the second diffuser plate (442).

5. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The high-angle light group (42) is a ring-shaped LED light, which is coaxially mounted around the lens of the CCD camera (5). Its light emission direction is at an angle of 30° to 60° with the optical axis of the CCD camera (5) to generate a vertical high-angle mode to detect surface flatness.

6. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The main control system (6) is configured to switch illumination modes in the following order: first, start the low-angle grazing light group (41) for contour detection, then switch to the diffuse light group (43) for deep hole and integrity detection, and finally switch to the high-angle light group (42) for surface defect detection.

7. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The main control system (6) is also configured to: after each detection is completed, optimize the brightness parameters of the corresponding lamp group in the pre-stored light field scheme based on the sharpness index of the multiple feature images collected this time, specifically through the following steps: Image quality analysis: For the feature images acquired under each illumination mode, within their predefined region of interest (ROI), the sum of squared gradient magnitudes is calculated to quantify their sharpness evaluation value; Performance evaluation: The calculated sharpness evaluation value is compared with the pre-stored target sharpness threshold for this modality; Parameter adjustment: If the sharpness evaluation value is lower than the target sharpness threshold for N consecutive detection cycles, the brightness parameter of the corresponding lamp group in the light field scheme is enhanced according to the preset adjustment step size; where N is an integer greater than 1. Solution update: The successfully optimized brightness parameters are updated into the light field scheme for subsequent testing of the timing chain (99) of the same engine block.

8. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The micro-ambient light sensor (7) is a spectral sensor; the main control system (6) is also configured to: dynamically adjust the color temperature of at least one lamp group in the multimodal light source system (4) based on the spectral distribution of the isolation chamber (2) detected by the micro-ambient light sensor (7) and in combination with the pre-stored reflectance spectral characteristics of different materials on the workpiece being tested, so as to optimize the imaging contrast between the target and the background for specific target detection features; The main control system (6) is specifically configured to enhance the brightness of the plastic material feature in the CCD camera (5) image by adjusting the color temperature of the lamp group to a lower color temperature when the target detection feature is plastic and its background is metal.

9. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, The inner wall of the isolation chamber (2) is coated with a light-absorbing coating.

10. The engine cylinder block timing chain CCD error prevention detection device according to claim 1, characterized in that, During fusion analysis, the main control system (6) is configured to extract the image regions most relevant to the specific detection features from the feature images acquired under different lighting modalities, and then perform splicing or logical synthesis to generate the final detection result.

Images